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Chemical Composition of a Bacteriophage for Streptococcus diacetilactis | Abstract Electron photomicrographs revealed that the tadpole-shaped phage particle had a head width and length of 60 m μ and a tail length of about 170 m μ . The dried phage contained 4.45% P and 12.8% of the protein was N. Bacteriophages prepared in broth medium were recovered by differential centrifugation and purified in a cesium chloride density gradient. An amino acid analysis revealed the following mole percentages for these acids: lysine, 8.1; histidine, 1.7; arginine, 3.8; aspartic acid plus asparagine, 10.0; threonine, 7.5; serine, 6.8; glutamic acid plus glutamine, 12.0; proline, 3.4; glycine, 9.0; alanine, 9.5; valine, 8.9; methionine, 1.1; isoleucine, 7.9; tyrosine, 2.2 and phenylalanine, 2.8. The nucleic acid of the phage was double-stranded DNA with a thermal melting point (Tm) of 84.3C; from this, an average composition of 35.7% guanine plus cytosine was calculated. | Abstract A method is described for extracting proteins and peptides from stained sodecyl sulfate-polyacrylamide gels. Coomassie blue and sodium dodecyl sulfate present in stained gel sections are removed to allow subsequent analysis of the peptides (e.g., amino acid analysis or tryptic digestion and fingerprinting). The method is simple, requires no radioisotopes or special equipment, and can be carried out with a minimum of handling of the sample. The process can be used for samples at the nanomole level with recoveries of 90%. | eng_Latn | 27,500 |
Development of Ga Salt of Molybdophosphoric Acid for Biomass Conversion to Levulinic Acid | Efficient catalytic methods for biomass conversion present a challenge for the sustainable production of fuels and chemicals. Ga salt of molydophosphoric acid (GaHPMo) is prepared using a sonochemical irradiation method. Simultaneous formation of GaHPMo and entrapment of polyoxometallate in gallium micro-/nanoparticles (Ga@HPMo) is achieved. The amount of entrapped hetropoly acid in Ga particles is estimated to be ∼3 wt %, as determined from thermogravimetric analysis (TGA) and ultraviolet–visible (UV–vis) analysis. The preparation of GaHPMo is accomplished by subjecting an ethanolic solution of polyoxometallate [molybdophosphoric acid (HPMo)] and molten Ga metal to sonication at 50 °C for 12 min. Physicochemical properties of GaHPMo are studied using X-ray diffraction, TGA, temperature-programmed desorption, differential scanning calorimetry, Fourier transform infrared spectroscopy, UV–vis spectroscopy, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, and energy-d... | Abstract Phenytoin and magnesium levels were measured in eighty epileptics and seventy-one control subjects in an investigation into possible effects of phenytoin on serum magnesium levels. Phenytoin levels were measured using GLC and magnesium levels by atomic absorption spectrophotometry. The study showed no significant effect of phenytoin on serum magnesium concentration. | eng_Latn | 27,501 |
A novel 125I radioimmunoassay for the analysis of delta 9-tetrahydrocannabinol and its metabolites in human body fluids. | A cannabinoid radioimmunoassay (RIA) that detects some of the major delta 9-THC metabolites is developed and evaluated for use in forensic science. It incorporates a novel 125I radiotracer, is sensitive, reliable, relatively quick, and simple to use. The RIA uses a commercially available antiserum and detects a number of cannabinoid metabolites, including delta 9-THC-11-oic acid and its glucuronide conjugate in biological fluids. The method was successfully applied to the analysis of blood and urine samples submitted for forensic analysis. | We describe a protocol to screen for protein-protein interactions using the Gal-4 based yeast two-hybrid system. In this protocol, we describe serial transformation of bait into an already constructed cDNA library in yeast AH109 cells. We find this method to gives the most number of true interactions. Where a pre-made library in yeast cells is not available, the method outlined can be quickly adapted. AH109 cells can be first transformed with bait containing a vector followed by selection of yeast containing the bait. A second transformation of yeast cells is then accomplished with the cDNA library. The method is quick and can lead to the discovery of significant interactions. | eng_Latn | 27,502 |
Influence of Uric Acid on Photostability of Fd& C Blue no. 2 | AbstractThe effect of uric acid as a photoprotective agent for various solutions of FD&C Blue No. 2 was investivated. Due to the poor aqueous solubility of uric acid, solutions were made in glycerin, triethanolamine and N/5 NaOH. Uric acid in glycerin or triethanolamine was found to enhance the photostability of the dye solutions. The higher the concentration of uric acid in triethanolamine, the greater was the photoprotective action of uric acid. Increasing the amount of glycerin in solution resulted in acceleration of the rate of fading of the color presumably due to dielectric constant effect. The photoprotective action of uric acid was found to be influenced by the pH of the medium and its buffer species. | Objective:To study on fingerprint condition of capillary electrophoresis(CE) in Sarcandra.Method:Study on following effect factors:composite of buffer,the pH of buffer,division voltage,division temperature,injection volume and additive.Results:The buffer was 7.5 mmol·L-1 borat and sodium dihydrogen phosphate solution containing 8% acetonitrile and 0.8 mmol·L-1 β-CD.The pH of the buffer was adjusted 8.39 with HCl solution.The detection wavelength was 340 nm and a voltage of 17 kV was applied.The sample hydrodynamic injection was 2.76kPa with a duration time of 3 sec.Conclusion:The best fingerprint condition of CE in Sarcandra could be established. | eng_Latn | 27,503 |
ChemInform Abstract: Synthesis of Quinolinones with Palladium-Catalyzed Oxidative Annulation Between Acrylamides and Arynes. | The catalyzed oxidative annulation of electron-deficient acrylamides with strained benzyne precursors under mild conditions is presented. | 1. 4-Cyano-N, N-dimethylaniline (CDA), when administered to rats as a single oral dose (18.5 mg/kg), was rapidly absorbed and eliminated as a mixture of metabolites in the urine (86% dose after 24 h).2. Residues in tissues after 48 h, expressed as μg equiv. of CDA, were: liver, 0.35; kidney, 0.28; testes, 0-08; fat, 006; bone marrow, 0.15 and blood, 0.32.3. Absorption, metabolism and elimination following four consecutive daily doses of CDA (65 mg/kg) were similar to those at the lower dose.4. The major metabolite was 2-amino-5-cyanophenyl sulphate with its mono- and di-N-methyl analogues as minor metabolites. 4-Cyanoaniline, its N-acetyl derivative and an unstable derivative were also found as metabolites.5. Three sulphur-containing metabolites with methylsulphinyl-, methylsulphonyl-, and N-acetylcysteinyl-groups attached to the C2 atom of an N-acetyl group were identified, the latter accounting for 10.3% and 41% of the low and high doses, respectively.6. The sulphur-containing metabolites indicate the i... | eng_Latn | 27,504 |
Bimetallic Ru–Ni Catalyzed Aqueous-Phase Guaiacol Hydrogenolysis at Low H2 Pressures | Aqueous-phase hydrogenolysis of renewable biomass at low H2 pressures is an attractive route to selectively produce renewable fuels and valuable chemicals. Here, we show that Ru and Ni nanoparticles (NPs) dispersed on HZSM-5 with an optimum H• radical transfer catalyzed a rapid rate (152 mmol g–1 h–1) of hydrogenolysis of C–O bonds in lignin-derived guaiacol at 240 °C and 2 bar H2 pressure in water. The coimpregnated individual Ru and Ni nanoparticles (NPs) on HZSM-5 were highly dispersed and did not present an alloy structure, but the individual Ru and Ni NPs were in close proximity. The guaiacol hydrogenolysis rates were proportional to the amounts of the adjacent RuO2 and NiO NPs on the calcined samples, suggesting that the closely contacted Ru and Ni NPs on HZSM-5 are the active sites. In the water phase at low H2 pressures, Ru dissociated the hydrogen molecules to H• radicals (H•), and then such radicals were transferred to adjacent Ni atoms to activate the capability of inert Ni centers. The adjustm... | Abstract We have devised a protocol for the isolation and identification of a proliferative antigen of the initial cells of wheat stem meristems (termed PAI). We have carried out a variety of immunochemical and immunocytochemical methods, using colloidal gold (CG) complexed with monospecific antibodies to PAI as the marker for the detection of PAI. We have been able to determine the effectiveness of immunoaffinity chromatography in isolating PAI from plant tissues and have shown the advantages of CG over enzyme labels for identification of the antigen. Finally, we have obtained a purified preparation of PAI and have determined its molecular mass (∼83 kDa). | eng_Latn | 27,505 |
Nucleophilic Phosphinidene Complexes: Access and Applicability | Syntheses, properties, and reactivities of nucleophilic phosphinidene complexes [LnMPR] are reviewed. Emphasis is placed on the electronic tuning of this emerging class of phosphorus reagents, using different ancillary ligands and coordinatively unsaturated transition-metal moieties. The difference in applicability of the established stable 18-electron and transient 16-electron phosphinidenes is addressed. | The success of drug development is greatly influenced by the efficiency of drug screening methods. Recently, phenotype-based screens have raised expectations, based on their proven record of identifying first-in-class drugs at a higher rate. Although fluorescence images are the data most commonly used in phenotype-based cell-based assays, nonstained cellular images have the potential to provide new descriptive information about cellular responses. In this study, we applied morphology-based evaluation of nonlabeled microscopic images to a phenotype-based assay. As a study case, we attempted to increase the efficiency of a cell-based assay for chemical compounds that induce production of nerve growth factor (NGF), using lyconadin B as a model compound. Because the total synthesis of lyconadin B was accomplished very recently, there is no well-established cell-based assay scheme for further drug screening. The conventional cell-based assay for evaluating NGF induction requires two types of cells and a total ... | eng_Latn | 27,506 |
Adrenal Function in Children with Asthma and Allergic Rhinitis Treated with Combination of Inhaled and Nasal Corticosteroids | Introduction: Children with asthma and allergic rhinitis are often treated with a combination of inhaled and nasal corticosteroids. Safety data on this combination treatment in children are not available. This study evaluates adrenal function in children receiving combination therapy with nasal and inhaled corticosteroid using a low-dose adrenocorticotropin (ACTH) test.Methods: Twelve children aged 6–12 years with severe asthma and allergic rhinitis were given combination therapy with high-dose inhaled HFA-beclomethasone dipropionate (HFA-BDP) (320 μg/day for first 2 months and 160 μg/day thereafter) and flunisolide nasal spray (116 μg/day). A low-dose ACTH test was performed before treatment and 6 months later.Results: There was no significant change (mean ± SD) in both baseline (7.78 ± 5.34 before treatment and 7.53 ± 4.02 after treatment, p = 0.42) and stimulated (22.58 ± 6.97 before treatment and 19.2 ± 3.53, p = 0.09 after treatment) cortisol levels.Conclusion: Combination therapy with high-dose HFA-... | Ribosomal 5S RNA presents a particular challenge to structural investigations since this polynucleotide is too large for complete NMR characterization but lacks significant tertiary structure to modulate, for example, diagnostic alkylation of guanine N7 by dimethyl sulfate. Nickel- and cobalt-dependent reagents that are sensitive to the N7 and aromatic face of guanine have now been applied to 5S rRNA (Xenopus lavis) and provide structural information that was not previously available from traditional chemical or enzymatic probes. Although G75 had repeatedly demonstrated an average reactivity with dimethyl sulfate and minimal reactivity with RNase T1, this residue was the major target of both metal-dependent reagents. Such reactivity provides crucial support for a structural model of loop E identified by prior physical, but not chemical, methods. Similarly, the tetraloop structure of loop D was more accurately reflected by the reactivity of G87 and G89 in the presence of the nickel reagent rather than in t... | eng_Latn | 27,507 |
Clinical Observation of Serious Acne Treated by 585 Pulse Dye Laser and Minocycline,Adapalene | Objective To observe the efficacy and safety of 585 pulse dye laser and minocycline,adapalene treatment of serere acne.Methods Fifty six cases of serere acne were randomly divided into treatment group and control group.Twewty eight cases in treatment group treated by 585 pulse dye laser and minocycline adapalene while.Control group used 585 pulse dye laser only.The spot size of dye laser was 7 mm,the energy density was 5～7J/cm2,for 1～8times treatments.Results Treatment group efficiency was 89.29%,Control group efficiency was 57.14%,Efficiency difference between the two groups was statistically significant(P0.05).Conclusion The 585 pulse dye laser and minocycline,adapalene treatment is effective and safe in serere acne. | AIM: To compare the characteristics of dauricine, sotalol, and quinidine on ::: action potential duration (APD). ::: METHODS: Using intracellular microelectrode method to record APD in guinea pig ::: papillary muscles. ::: RESULTS: Dauricine 20 mumol.L-1 prolonged action potential at 90% repolarization, ::: the percent of APD prolongation were 22 +/- 8, 11 +/- 6, 9 +/- 5, 7 +/- 5, 6 +/- ::: 3, 4.3 +/- 2.8, 4.5 +/- 2.8 at the cycle lengths of 200-2000 ms, dauricine became ::: more effective in lengthening APD at short cycle lengths. The effect of dauricine ::: on prolonging APD exhibited normal use-dependence, whereas quinidine 1 mumol.L-1 ::: and sotalol 10 mumol.L-1 were less effective in lengthening APD at short cycle ::: lengths. The effect of quinidine and sotalol on APD exhibited reverse ::: use-dependence. ::: CONCLUSION: [corrected] The effect of dauricine on APD depends on activation ::: frequency. | eng_Latn | 27,508 |
Efficient ruthenium-catalyzed synthesis of [3]dendralenes from 1,3-dienic allylic carbonates. | Selective elimination from 1,3-dienic allylic carbonates occurs in the presence of a catalytic amount of [Ru(C(5)Me(5))(4,4'-di-Bu(t)-2,2'-bipyridine)(CH(3)CN)]PF(6) and provides efficient access to a variety of [3]dendralenes. | 1. 4-Cyano-N, N-dimethylaniline (CDA), when administered to rats as a single oral dose (18.5 mg/kg), was rapidly absorbed and eliminated as a mixture of metabolites in the urine (86% dose after 24 h).2. Residues in tissues after 48 h, expressed as μg equiv. of CDA, were: liver, 0.35; kidney, 0.28; testes, 0-08; fat, 006; bone marrow, 0.15 and blood, 0.32.3. Absorption, metabolism and elimination following four consecutive daily doses of CDA (65 mg/kg) were similar to those at the lower dose.4. The major metabolite was 2-amino-5-cyanophenyl sulphate with its mono- and di-N-methyl analogues as minor metabolites. 4-Cyanoaniline, its N-acetyl derivative and an unstable derivative were also found as metabolites.5. Three sulphur-containing metabolites with methylsulphinyl-, methylsulphonyl-, and N-acetylcysteinyl-groups attached to the C2 atom of an N-acetyl group were identified, the latter accounting for 10.3% and 41% of the low and high doses, respectively.6. The sulphur-containing metabolites indicate the i... | eng_Latn | 27,509 |
Chemistry and Anti-HIV Activity of 2′-β-Fluoro-2′,3′-dideoxyguanosine | Abstract The 2′-β-fluoro analogue of 2′,3′-dideoxyguanosine has been prepared by two synthetic routes. This compound and two analogues have anti-HIV activity in at least two of three host cell systems used (ATH8, CEM, PBL). These compounds, as well as their ddGuo parents, have been characterized with regard to their acid-stabilities, octanol-water partition coefficients, and enzyme substrate properties for adenosine deaminase and purine nucleoside phosphorylase. F-ddGuo analogues are less potent but more stable than their non-fluorinated parent compounds. | Abstract Mixtures of gangliosides were separated by high-performance liquid chromatography (HPLC) on amino-silica columns according to their negative charge and the length of the carbohydrate portion. The use of an on-line variable wave-length diode-array detector allows the identification of gangliosides on the basis of their UV spectra with maximum absorbance at 196 nm. Accurate analytical data acquired with the diode-array detector allow the qualitative and quantitative determination of gangliosides and therefore eliminate the need for thin-layer chromatography after HPLC separation. | eng_Latn | 27,510 |
HPLC Determination of Acetylshikonin in Hairy Roots of Arnebia euchroma | Objective:To establish a method for the determination of acetylshikonin in the Hairy Roots of Arnebia euchroma ( Royle) Johnst. Method:The RP-HPLC system consisting of YMC-Pack ODS-A C18 column (4. 6 mm × 150 mm,5 μm) and a mixture of acetonitrile solution and water solution and formic acid solution(700∶ 300∶ 0. 5)as the mobile phase was adopted; the detection wavelength was 275 nm; the flow rate was set at 1. 0 mL ·min-1and the column temperature was at 35 ℃. Result:The linear range of acetylshikonin was 51.55-1 031.0 mg·L -1(r = 0. 9 999). The average recovery (n = 9) was 99. 81%. Conclusion:The method is quick,simple and reproducible for the determination of acetylshikonin in Hairy roots of A. euchroma. | Abstract Chemisorption of atomic H, C, N and O is studied by both EHT and IEHT methods using a cluster model. Preliminary calculations for the diatomic species HgHg and HgH enables the parameters involved in the calculations to be found. The minima positions over the surface model follows the order of the atomic sizes, and the charges on the adsorbates, at the minima, agree with the order of electronegativities. | eng_Latn | 27,511 |
Effects of ultraviolet light on epidermal polyamine metabolism | Abstract Exposure of the dorsal skin of hairless mice to the light of a germicidal lamp under standardized conditions produces reproducible, time-dependent increases of putrescine and spermidine concentrations, and a decrease of spermine levels, concomitant with the increase of the rate of DNa synthesis. Systemic or topical treatment of the animals with α-difluoromethylornithine, an enzyme-activated irreversible inhibitor of ornithine decarboxylase, completely prevents the uv light-induced rapid formation of putrescine, and diminishes the enhancement of polyamine turnover rates. A significant effect of the drug on the rate of DNA synthesis could not be shown. The model is suitable for the study of interrelations between polyamine metabolism and cell proliferation and for the screening of compounds designed as inhibitors of polyamine biosynthesis. | An inverse correlation between PWM and anti mu responses of peripheral blood lymphocytes, and a close relationship to clinical activity were demonstrated in 9 patients with systemic lupus erythematosus. | eng_Latn | 27,512 |
Failure of Methionine to Reduce Nitrogen Loss in Postoperative Herniorrhaphy Patients on Restricted Diet.∗ | Conclusion Under thc conditions oi this experiment the administration of 6.0 q of mcthionine daily to men receiving a low caloric diet failed to show a significant proteiniparing action as indicated by the effect on urinary nitrogen excretion. | Equations have been developed for describing the isotherms of extraction of rare-earth metal(III) [REM(III)] nitrates from aqueous concentrated solutions by 100% diisoamyl methylphosphonate, taking into account the variation of activity coefficients of components in the organic phase when its composition is varied within broad limits. The thermodynamic parameters of the extraction equilibria have been calculated using as the standard states hypothetical one-molal aqueous REM(III) nitrate solutions and pure components of the organic phase at a mole fraction of 1.0. | eng_Latn | 27,513 |
Hydrogen Oxidation-Selective Electrocatalysis by Fine Tuning of Pt Ensemble Sites to Enhance the Durability of Automotive Fuel Cells. | A simple, inexpensive approach is proposed for enhancing the durability of automotive proton exchange membrane fuel cells by selective promotion of the hydrogen oxidation reaction (HOR) and suppression of the oxygen reduction reaction (ORR) at the anode in startup/shutdown events. Dodecanethiol forms a self-assembled monolayer (SAM) on the surface of Pt particles, thus decreasing the number of Pt ensemble sites. Interestingly, by controlling the dodecanethiol concentration during SAM formation, the number of ensemble sites can be precisely optimized such that it is sufficient for the HOR but insufficient for the ORR. Thus, a Pt surface with an SAM of dodecanethiol clearly effects HOR-selective electrocatalysis. Clear HOR selectivity is demonstrated in unit cell tests with the actual membrane electrode assembly, as well as in an electrochemical three-electrode setup with a thin-film rotating disk electrode configuration. | Publisher Summary This chapter focuses on the purification of lectins and determination of their carbohydrate specificity. A number of procedures employed for the purification of the different lectins are basically similar. A common to virtually all lectin purification schemes is affinity chromatography on immobilized sugars, which exploits the ability of lectins to combine with carbohydrates specifically and reversibly. Hemagglutination is routinely assayed with native or modified erythrocytes from humans or other animals, usually rabbits and sometimes sheep. Blood group-specific lectins are tested with a panel of typed human erythrocytes. In plants, lectins often occur as a group of closely related proteins with the same carbohydrate specificity, or isolectins. Different molecular species of the lectin may also result from intramolecular aggregation, possibly occurring during purification. | eng_Latn | 27,514 |
Multistep Enzyme Catalyzed Reactions for Unnatural Amino Acids | The use of unnatural amino acids, particularly synthetic α-amino acids, for modern drug discovery research requires the availability of enantiomerically pure isomers. Starting from a racemate, one single enantiomer can be obtained using a deracemization process. The two more common strategies of deracemization are those obtained by stereoinversion and by dynamic kinetic resolution. Both techniques will be here described using as a substrate the D,L-3-(2-naphthyl)-alanine, a non-natural amino acid: the first one employing a multi-enzymatic redox system, the second one combining an hydrolytic enzyme together with a base-catalyzed substrate racemization. In both cases, the final product, L-3-(2-naphthyl)alanine, is recovered with good yield and excellent enantiomeric excess. | The influence of the infusion therapy on enzymatic link of antioxidant defense in the small bowel tissue in severe combined trauma of abdominal cavity organs was studied. The best indices of survival in 24 h and changes of the superoxiddysmutase and catalase activity in animals, to whom preparation HAES-LX5% was prescribed. | eng_Latn | 27,515 |
Examination of an Internal Standard Substance for the Quantitative Analysis of Sarin Using 31P-NMR. | The toxic solution used at the Tokyo Subway Sarin Incident was purified by vacuum distillation. We were thus able to obtain sarin with high purity. We conducted a quantitative analysis of sarin using 31P-NMR spectrometry. High-purity sarin was examined by trimethyl phosphate as an internal standard. In comparison with 1H nondecoupling, the relative intensity between sarin and the internal standard did not change in 1H decoupling. Trimethyl phosphate is a good internal standard substance. A 31P-NMR chemical shift of trimethyl phosphate is separate from those of sarin and related compounds. Trimethyl phosphate has one phosphorus atom in the molecule, as does sarin. Since it is advantageous in the conversion of quantitative value, the molecular weight of trimethyl phosphate (m.w. 140.08) is close to that of sarin (m.w. 140.09). By using trimethyl phosphate as an internal standard, it is possible to conduct a quantitative analysis of sarin through 1H decoupled 31P-NMR spectrometry. | Single crystals of tin iodide (SnI2) have been grown in silica gels. A detailed microtopographical study of {100} faces have been described. Horizontal striations are predominant on these faces for most of the crystals, while few of them show vertical striations. The horizontal striations are associated with the two-dimensional nucleation theory whereas the vertical striations relate to the growth fronts. Growth layers modified by the presence of misaligned microcystals have been illustrated. The natural etch pits on {100} faces of the crystal are attributed to the dissolution of crystals in the acid set gel. In the light of these observations, the mechanism of the development and growth of these faces have been assessed and the implications are discussed. | eng_Latn | 27,516 |
Total Conversion of Racemic 2-Chloropropionic Acid into D-Lactate by Combination of Enzymatic and Chemical Dehalogenations | Abstract We have developed a simple method for the total conversion of racemic 2-chloropropionic acid into d -lactic acid with an enantiomeric excess (e.e.) of about 94%. l -2-Chloropropionic acid is fully converted to d -lactic acid with l -2-halo acid dehalogenase, and the unreacted d -2-chloropropionic acid is dehalogenated chemically, retaining its configuration to produce d -lactic acid. | OBJECTIVE: To establish HPLC fingerprint of Compound danshen tablets.METHODS: The separation was performed on Agilent Eclipse XDB-C18(150 mm×4.6 mm,5μm) column with mobile phase consisted of acetonitrile-0.04% phosphate (gradient elution) at flow rate of 1.0 mL·min-1.Detection wavelength was set at 272 nm and column temperature was 30℃.RESULTS: Established HPLC fingerprint was distinct and reproducible.There were 8 characteristic peaks among which No.5 characteristic peaks,No.6,No.7,No.8 came from HPLC fingerprint of Salvia miltiorrhiza and No.1 characteristic peaks,No.2,No.3,No.4 came from HPLC fingerprint of Panax notoginseng.CONCLUSION: The characteristic peaks of effective parts of Compound danshen tablet mainly come from S.miltiorrhiza.The study can be used for tracing and isolation of effective part of Compound danshen tablet and establishes basis for the further development of Chinese patent drugs. | eng_Latn | 27,517 |
Decreased or Absent ACTH-Like Activity of Blocked Synthetic Tricosapeptide.∗ | SummarySubstitution of acetyl for hydrogen in the NH2 group of the N-terminal serine, NH2 for OH” in the carboxyl of glutamine in position 5, and formyl for an amino hydrogen of lysine in positions 11, 15, 16, and 21 decreases or eliminates the ACTH-like activity of a synthetic tricosapeptide which duplicates the first 23 amino acids of naturally occurring ACTH. | SummaryThe metabolism of betahistine, demethylbetahistine and 2-(2-hydroxy-ethyl) pyridine in the rabbit leads to the urinary excretion of acidic metabolities, including 2-pyridylacetate, which is excreted in part as N-2-pyridylacetylglycine. Other unidentified Koenig-positive compounds were in the acidic fraction. | eng_Latn | 27,518 |
Cleansing of the colon without enemas. | Several methods have been used to cleanse the large bowel prior to roentgen examination and rectoscopy for more than ten years. A method with administration of a salt solution (SALAX) in combination with different oral laxatives (Cascara sagrada, Dantron, Bisacodyl) without cleansing enemas is described. Hospitalized patients should have an individual preparation while ambulatory patients are almost completely cleansed if they carefully follow the given instructions. | Flow Injection (FI) techniques for use with Atomic Absorption Spectrometry (AAS) ::: have attracted considerable research interest for sample introduction and calibration ::: strategies. The interest continues in on-line preconcentration and matrix modification ::: which are carried out by the incorporation of liquid-liquid extraction, ion-exchange, ::: immobilised reagents, gas/vapour generation and continuous precipitation-filtration ::: devices into suitably designed manifolds. Indirect determination of inorganic anions and ::: organic compounds is becoming routine by FI–flame AAS. The direct analysis of solid ::: samples, which is a shortcoming of flame AAS, was recently carried out by on-line ::: electrolytic dissolutions. [Continues.] | eng_Latn | 27,519 |
Atmospheric corrosion of A3 steel with deposited ammonium sulfate | The atmospheric corrosion of A3 steel with deposited (NH4)(2)SO4 particles has been investigated at 298 K and relative humidity of (85 +/- 5) %. Corrosion kinetics curves show that A3 steel with deposited (NH4)(2)SO4 particles corroded more seriously than that without (NH4)(2)SO4 particles. IR, SEM/EDAX and XPS were utilized to study the development and characterization of corrosion products. The results indicate that A3 steels with (NH4)(2)SO4 particles corroded much faster than that without (NH4)(2)SO4 particles, and the corrosion of A3 steel initiated along the deposition area of (NH4)(2)SO4 particles, and formed basic iron sulfate. A corrosion mechanism was proposed to explain the observation. | Analysis of a database containing over 20 000 high-resolution collision-activation mass spectra of tryptic peptide dications was employed to study the relative specificity of neutral losses from backbone fragments. The high resolution of the FTMS instrument allowed for the first time the first isotope of the water loss and the monoisotope of the ammonia loss to be distinguished. Contrary to a popular belief, water losses from y‘ ions are not specific enough to rely upon for detecting the presence of amino acids with oxygen in the side chains. At the same time, ammonia loss from b ions is sufficiently specific (>95%) to detect the presence of amino acids Gln, Asn, His, Lys, and Arg. This feature will be useful for de novo algorithms for high-resolution MS data. Clear trends were observed when the effect of amino acids proximate to the cleavage site on the rate of loss formation was studied. These trends turned out to be different for losses from b and y ions. Keywords: CAD • de novo sequencing • peptide id... | eng_Latn | 27,520 |
Protein determination using methylene blue in a synchronous fluorescence technique. | A new method for detecting protein by synchronous fluorescence enhancement was developed, based on the combination of near infrared (NIR) fluorescence and the dedimerization phenomenon of methylene blue (MB). Under analytical conditions, there are linear relationships between the enhancing extent of synchronous fluorescence of MB-sodium dodecyl benzene sulfonate (SDBS)-protein at 667nm and the concentration of protein in the range of 8.0x10(-8)-4.0x10(-5)gmL(-1) for bovine serum albumin (BSA), 1.0x10(-7)-3.5x10(-5)gmL(-1) for egg albumin (EA). The detection limits (S/N=3) of BSA and EA are 8.9ngmL(-1) and 10.0ngmL(-1), respectively. The fluorescence enhancement mechanism is discussed in detail. Results from multiple techniques indicate that the fluorescence enhancement of the system originates from the hydrophobic microenvironment provided by BSA and SDBS, and the formation of an MB-SDBS-BSA complex, as well as the deaggregation of some MB dimer. | In most structural biology NMR laboratories, instrument time is a limiting factor in the number of structural projects a laboratory is able to support. In the post-genomic era we can expect the number of structural targets to markedly increase. Here we address to what degree recently introduced cryoprobes, which are 3-4 times as sensitive as conventional probes, can alleviate this problem. To evaluate this approach, a set of triple-resonance experiments for protein assignments were acquired with a cryoprobe. We show that, with the cryoprobe, high quality triple-resonance data can be obtained within as 4 hours/experiment. These results show that a full set of data for protein assignments can now be practically collected in 1-2 days. | eng_Latn | 27,521 |
Determination of Glutethimide in Serum: An Evaluation of Thin-layer Chromatography Method Compared to Spectrophotometric Analysis * | AbstractThe determination of glutethimide in biologic fluids using the spectro-photometric method of Goldbaum e t al. [1] is sensitive, specific, and accurate but requires a skilled technician and is a time-consuming procedure. Recently, Korzun et a1 [2] reported the assay of glutethimide in blood using rapid thin-layer chromatography (TLC). Because of its speed and simplicity, we further investigated this chromatographic method using the Goldbaum technique as a standard of reference. | In this article, perspective using of the laser deposition method for manufacture details from the titanium alloy VT20 is considered. Dependence on a structure of the fractional composition is shown. Study of the structure and properties of parts, which were produced by DLD technology using different modes and under different conditions. | eng_Latn | 27,522 |
[Adjuvant immunotherapy of stomach carcinoma with antibody-induced apoptosis]. | The human monoclonal antibody SC-1 was isolated from a patient with a diffuse-type adenocarcinoma of the stomach and induces apoptosis of stomach carcinoma cells by binding a stomach-carcinoma-associated isoform of CD55/DAF-B. In a first clinical trial with 20 patients with poorly differentiated stomach adenocarcinoma of diffuse-type received 20 and 30 mg of purified SC-1 antibody intravenously, followed 24 or 48 h later by gastrectomy and lymphadenectomy. In 90% of the cases a significant induction of apoptotic activity was measured in primary tumors as compared with earlier biopsy material and in 50% of the patients a significant regression of tumor mass could even be determined histopathologically. No toxic crossreactivity was observed with normal tissue or organs of patients. These data show, that the human monoclonal antibody SC-1, which induces tumorspecific apoptosis, can be successfully used for adjuvant therapy. | Isotopic ion—molecule reactions producing ABH+ and ABD+ ions (AB=N2, CO, O2, and CO2) when AB—HD mixtures are subjected to electron bombardment in the mass‐spectrometer ion source have been studied as a function of reactant ion velocity. Good agreement between the experimental and theoretical cross sections for secondary ion formation is obtained when both AB+—HD and HD+—AB interactions are taken as possible reaction paths. Ionization‐efficiency curves of the secondary ion products furnish supporting evidence for the assumed reaction mechanisms. Identification of reactant ions by ionization‐efficiency curves is not sufficient to establish the thermochemistry of the ion—molecule reaction; distributions of vibronic states produced by electron impact are also required. The vibrational population of excited reactant ions formed in the electron impact process has been estimated from the squares of the overlap integrals of respective ground and excited ionized states. Data taken from published photoionization e... | eng_Latn | 27,523 |
Treatment of warts with contact allergens | Contact immunotherapy is an increasingly used, effective means of treating cutaneous viral warts. Dinitrochlorobenzene, diphencyprone, and squaric acid dibutylester are the most frequently used modalities, showing slight variances in adverse effect profiles and efficacy. All of these agents serve as safe treatment modalities when administered according to the guidelines recommended herein. We review the value of contact immunotherapy in the treatment of cutaneous viral warts. | Wagner constants are estimated from VLE predictions based solely on the critical and normal boiling points, and acentric factor. The predictions come from the standard forms of 1) Riedel and 2) Ambrose-Walton, 3) a modified Riedel equation resulting from forcing the value of K to provide zero error at the reduced temperature of 0.7, and 4) a modified Ambrose-Walton equation resulting from using a pseudo acentric factor that provides zero error at the normal boiling point. Reduced vapor pressure values obtained using these Wagner constants are compared to those generated by using literature-reported Wagner constants that are applicable for the entire two-phase VLE curve for 72 species. I t is shown that the Wagner equation parameterized using VLE predictions from such correlations can provide better accuracy than the underlying source correlations themselves, and it can exhibit less error than a parameterization using a limited interval of experimental data. | eng_Latn | 27,524 |
Purification of Lectins and Determination of Their Carbohydrate Specificity | Publisher Summary This chapter focuses on the purification of lectins and determination of their carbohydrate specificity. A number of procedures employed for the purification of the different lectins are basically similar. A common to virtually all lectin purification schemes is affinity chromatography on immobilized sugars, which exploits the ability of lectins to combine with carbohydrates specifically and reversibly. Hemagglutination is routinely assayed with native or modified erythrocytes from humans or other animals, usually rabbits and sometimes sheep. Blood group-specific lectins are tested with a panel of typed human erythrocytes. In plants, lectins often occur as a group of closely related proteins with the same carbohydrate specificity, or isolectins. Different molecular species of the lectin may also result from intramolecular aggregation, possibly occurring during purification. | The work by Levis andRabitz in the field of laser control achieved great importancedue to their result of having controlled a complex bondrearrangement reaction (Scheme 2, in ref 2; Scheme 3c in ref3), specifically the production of toluene starting from acetophe-none (see Figure 1 insert). Their original experiment wasreported to | eng_Latn | 27,525 |
Organophosphate Insecticide Intoxication in a Family | Louse is an external, obligate, blood-sucking parasite, which infects human societies. Improvements in health, economics, and social status of societies have reduced the parasitic lice infestation, however, it still is a global problem. Although it affects all age groups, school children are the most vulnerable age group. The high incidence of infection in children and their long-term close contacts transmit the infestation easily among them. In some parts of our country, organophosphate pesticides are widely used to control pests. Due to the ease of access to these toxins, poisoning with them are common and according to global statistics most deaths by pesticide are associated with organophosphate pesticides. Accordingly, we report 3 cases of a family from rural areas of Babol City. Upon being sprayed with an organophosphate solution, they developed severe organophosphate intoxication (OI) associated with central nervous system suppression. | FIELD: chemistry. SUBSTANCE: invention concerns process of production of diisopropyl {[1-(hydroxymethyl)-cyclopropyl]oxy}methylphosphonate represented by the formula , which is the key intermediate compound in synthesis of antiviral nucleoside analogue. The invention also concerns new intermediate compounds of formulae and , and their production of compound (2) obtained under this invention, which is an antiviral nucleoside analogue (especially against hepatitis B virus) represented by the formula . EFFECT: high purity grade and high output. 4 ex | eng_Latn | 27,526 |
The relationship between body phosphate and blood pressure. | Phosphate depletion alters the function of the cardiovascular system. Decreased myocardial performance has been described in phosphate depleted dogs (1) and humans (2). In the most severe cases of hypophosphatemia, congestive cardiomyopathy can occur (3). Phosphate supplementation reverse these abnormalities. | The property of biological degradation is used as the primary evaluation index in this article. By designing the radio of the monomer, the experiment tests the CODCr/BOD5 value of seven kinds of sizes, which are of different monomer ratios. The calibration experiment is the COD value of potassium hydrogen phthalate (KHP) standard solution and the BOD value of Glucose and sodium glutamate salt standard solution. By using the optimum ratio of monomer, we synthesized the new acrylic sizing agent, which has a good biodegradation performance and can be biochemical. | eng_Latn | 27,527 |
Positive electrode material, paste, and sodium ion cell | A positive electrode material that has exceptional water resistance, high electron conductivity and suitability for use in a sodium ion secondary cell, wherein the positive electrode material contains carbonaceous electrode active material composite particles that comprise: positive electrode active material particles and a carbonaceous coating covering the surface of the positive electrode active material particles. Said particles contain a sodium sulfate salt compound that is represented by Na x M y (SO 4 ) y (where M represents one or more elements selected from the group consisting of Sc, Ti , V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, and Ag, and 1.6 ≤ x ≤ 2.4, 1.6 ≤ y ≤ 2.4, and 2.4 ≤ z ≤3.6) having an M 2 O 10 dimer crystal structure in which a dimer is formed by edge-sharing between two MO 6 in a structure. | The success of drug development is greatly influenced by the efficiency of drug screening methods. Recently, phenotype-based screens have raised expectations, based on their proven record of identifying first-in-class drugs at a higher rate. Although fluorescence images are the data most commonly used in phenotype-based cell-based assays, nonstained cellular images have the potential to provide new descriptive information about cellular responses. In this study, we applied morphology-based evaluation of nonlabeled microscopic images to a phenotype-based assay. As a study case, we attempted to increase the efficiency of a cell-based assay for chemical compounds that induce production of nerve growth factor (NGF), using lyconadin B as a model compound. Because the total synthesis of lyconadin B was accomplished very recently, there is no well-established cell-based assay scheme for further drug screening. The conventional cell-based assay for evaluating NGF induction requires two types of cells and a total ... | eng_Latn | 27,528 |
Discovery and Preclinical Evaluation of BMS-711939, an Oxybenzylglycine Based PPARα Selective Agonist | BMS-711939 (3) is a potent and selective peroxisome proliferator-activated receptor (PPAR) α agonist, with an EC50 of 4 nM for human PPARα and >1000-fold selectivity vs human PPARγ (EC50 = 4.5 μM) and PPARδ (EC50 > 100 μM) in PPAR-GAL4 transactivation assays. Compound 3 also demonstrated excellent in vivo efficacy and safety profiles in preclinical studies and thus was chosen for further preclinical evaluation. The synthesis, structure–activity relationship (SAR) studies, and in vivo pharmacology of 3 in preclinical animal models as well as its ADME profile are described. | A new technique based on adaptive code-to-user allocation for interference management on the downlink of BPSK based TDD DS-CDMA systems is presented. The principle of the proposed technique is to exploit the dependency of multiple access interference on the instantaneous symbol values of the active users. The objective is to adaptively allocate the available spreading sequences to users on a symbol-by-symbol basis to optimize the decision variables at the downlink receivers. The presented simulations show an overall system BER performance improvement of more than an order of a magnitude with the proposed technique while the adaptation overhead is kept less than 10% of the available bandwidth. | eng_Latn | 27,529 |
Synthetic Reactions by Complex Catalysts. XIV. Reaction of Isocyanide with Amine Catalyzed by Group IB and IIB Metal Compounds | Group IB and IIB metal compounds catalyze the reaction of isocyanides (1) with amines (2) producing formamidines (3). In the reaction of cyclohexyl isocyanide with piperidine, the accelerating effect of catalyst was in the order AgCl>CuCl>>ZnCl2, Cd(OAc)2, HAuCl4·4H2O. The AgCl catalyzed reaction proceeded almost quantitatively in 2.5 hr at 17°C. The reaction of aliphatic isocyanide with aromatic amine, e.g., N-methylaniline, required higher reaction temperatures (160°C) even in the presence of catalyst, in which the order of catalytic activity was HAuCl4·4H2O>ZnCl2>AgCl>>CuCl. A ternary complex of (CuCl)2 (cyclohexyl isocyanide)2 (piperidine) was isolated, which was unstable and decomposed gradually at room temperature to give N-cyclohexyl-N,N′-pentamethylene formamidine. A mechanism through a mixed ligand complex has been proposed, in which both isocyanide and amine are coordinated with the same metal ion and the reaction takes place in the sphere of complex ligand. | 1. 4-Cyano-N, N-dimethylaniline (CDA), when administered to rats as a single oral dose (18.5 mg/kg), was rapidly absorbed and eliminated as a mixture of metabolites in the urine (86% dose after 24 h).2. Residues in tissues after 48 h, expressed as μg equiv. of CDA, were: liver, 0.35; kidney, 0.28; testes, 0-08; fat, 006; bone marrow, 0.15 and blood, 0.32.3. Absorption, metabolism and elimination following four consecutive daily doses of CDA (65 mg/kg) were similar to those at the lower dose.4. The major metabolite was 2-amino-5-cyanophenyl sulphate with its mono- and di-N-methyl analogues as minor metabolites. 4-Cyanoaniline, its N-acetyl derivative and an unstable derivative were also found as metabolites.5. Three sulphur-containing metabolites with methylsulphinyl-, methylsulphonyl-, and N-acetylcysteinyl-groups attached to the C2 atom of an N-acetyl group were identified, the latter accounting for 10.3% and 41% of the low and high doses, respectively.6. The sulphur-containing metabolites indicate the i... | eng_Latn | 27,530 |
Regioselective Friedel−Crafts Alkylation of Anilines and Amino‐Substituted Heteroarenes with Hexafluoroacetone Sesquihydrate | A variety of arenes, including anilines, pyrroles, indoles, aminooxazoles, aminothiazoles, aminoquinolines, and aminopyridines, underwent regioselective Friedel−Crafts alkylation in neat hexafluoroacetone sesquihydrate in a broad range of temperatures, reaction times, and yields (2%−94%) depending strongly on the electron density of the substrate. Prior N,N-dibenzylation of aniline and 2-aminopyridine strongly promoted substrate reactivity and resulted in higher yields (> 80%). The described Friedel−Crafts alkylations in hexafluoroacetone sesquihydrate occurred regioselectively at the para-positions of anilines or at the positions β to the sp2-hybridized nitrogen atom in heteroarenes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) | The method for analysis of sulfonamides antibiotic in honey by dispersive liquid-liquid microextraction(DLLME) combined with high performance liquid chromatography was developed.The effects of parameters such as the extraction solvent,dispersing agent,volume of extraction solvent and dispersing solvent,extraction time,ionic strength and solution pH on dispersion of liquid phase microextraction were investigated,and the optimal extraction conditions were as follows:1mL of acetonitrile(as dispersive solvent) and 40μL 1,1,2,2-tetrachloroethane(as extraction solution) were rapidly mixed,then centrifuged for 2min after adding water solution of honey samples,and 5μL sedimentary facies was injected to analyze by HPLC.The method is applied to determination of 3 batches honey samples with good effects. | eng_Latn | 27,531 |
[Phagocytic activity of the central macrophage of erythroblastic islet in experimental inhibition and stimulation of erythropoiesis]. | Phagocytic activity of the erythroblastic island central macrophage (EICM) was studied under normal conditions and in experimental inhibition and stimulation of erythropoiesis. Specific phagocytic activity (SPA) was estimated by the amount of latex particles absorbed by 1 EICM during 30-min incubation on plastic Petri dishes. SPA of CM in all the animals (no matter what experimental model was chosen) depended on EI affiliation to a certain class, with the maximum activity in EICM of the III class. SPA in EICM of the II-III classes in polycythemia animals was low. Blood loss significantly increased SPA in EICM of the II-IV classes of maturity. EICM of the I class showed a lower SPA that was, probably, due to the involvement of immature monocytes into EI organization. | The field ionization mass spectra of monosubstituted cyclopentenes and cyclohexenes with C1-C7n-alkyl and C4-C5 isoalkyl substituents in positions 1 and 3 have been investigated and compared with the previously reported electron impact mass spectra of these compounds. The cleavage of the CC bond β to the double bond in the non-isomerized molecular ion was found to be a typical degradation reaction of the higher homologues in the strong electric field. So, by means of the field ionization mass spectra, the >C1 alkyl substituent can be readily located in the parent molecule. The electron impact mass spectra exhibit a less specific fragment ion distribution for positional isomers due to the extensive molecular ion isomerization prior to decomposition, but provide useful information on the ring size. For structure determination it is appropriate to use both ionization techniques. | eng_Latn | 27,532 |
Determination of Benzimidazoles Residue in Raw Milk Using Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry | A method for determination of benzimidazoles residue in raw milk was developed using ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).Ethyl acetate was used to extract the target analyte from raw milk,extraction was degreased and cleaned up with Waters Oasis MCX solid phase extraction(SPE) column for UPLC-MS/MS.The liquid chromatography separation was carried on C18 column(2.1 mm×100 mm i.d.,1.7 μm)with acetonitrile and water(added 0.1% formic acid) as mobile phase at a flow rate of 0.3mL/min.The mass spectrometry was performed in multiple reaction monitoring(MRM)mode.The limits of detection(LOD) of the method were 0.5 μg/kg and the limits of quantification(LOQ) were 1.0 μg/kg.The method has good repeatability and high sensitivity,and can be applied for the determination of ben-zimidazoles in raw milk. | Alkylating agents, such as temozolomide, are among the most effective cytotoxic agents used for malignant gliomas, but responses remain very poor. The DNA repair protein O 6 -methylguanine-DNA methyltransferase (MGMT) plays an important role in cellular resistance to alkylating agents. IFN-β can act as a drug sensitizer, enhancing toxicity against a variety of neoplasias, and is widely used in combination with other antitumor agents such as nitrosoureas. Here, we show that IFN-β sensitizes glioma cells that harbor the unmethylated MGMT promoter and are resistant to temozolomide. By means of oligonucleotide microarray and RNA interference, we reveal that the sensitizing effect of IFN-β was possibly due to attenuation of MGMT expression via induction of the protein p53. Our study suggests that clinical efficacy of temozolomide might be improved by combination with IFN-β using appropriate doses and schedules of administration. | eng_Latn | 27,533 |
Spectrophotometric study on stability constants of copper(II) complex with 1-amidino-O-methylurea | The stoichiometries and stability constants of copp er(II) ions with 1-amidino-O-methylurea have been determined in aqueous solution at different te mperatures 20 0 C, 25 0 C, 30 0 C, 35 0 C and 40 0 C with constant ionic strength of 0.5 M KNO 3 by using Job’s continuous variation method spectrophotometrically. In all cases, the Job’s cur ves displayed a maximum at a mole fraction Xmetal =0.5 indicating the formation of complex with 1:1 m etal to ligand ratio. It was observed that metal-ligand stability constant decreases with increasing temperature indicating exothermic nature of the reaction. Plots of thermodynamic stab ility constants versus 1/T gave linear curves indicating high temperature sensitivity for the -NH group of the ligand. The thermodynamic | [Objective] The aim was to discuss the new method of determining thiocyanate(SCN-) content in vegetables.[Method] CuSCN,which Cu(Ⅱ) could be reduced to Cu(Ⅰ) by ascorbic acid in the presence of acetic acid buffer medium and SCN-,then Cu(Ⅰ) was precipitated with SCN-.Using the precipitation reaction and combined with flowinjection method,the new method of flow-injection resonance light scattering was established to determine SCN-.[Result]The linear range of determination was 3-160 μg/ml.The detection limit was 0.167 g /ml SCN-.[Conclusion] The confirmed method were simple,a little reagent and wide linear range.The method was could be applied to the determination of thiocyanate in vegetables. | eng_Latn | 27,534 |
The escape factor in atomic absorption spectroscopy | Abstract Values of the escape factor have beeb calculated from atomic absorption measurements for a wide range of concentrations of Li, K, Cu, and Ag at the resonance lines 6707.84, 7664.01, 3427.54 and 3382.89 A, respectively. Different approximations were investigated and the optical depths limits for which each approximation is reliable have been predicted. The dependence of the escape factor on the total number of atomos in the ground state is discussed. Atomic absorption phenomena are explained in terms of the escape factor, especially at high concentrations. | Abstract A radioimmunoassay for human cathepsin B is described, which demonstrates the usefulness of protein A-bearing Staphylococcus aureus as an immunosorbent in a system where the primary antibody IgG has a low binding affinity for protein A. The removal of bound antigen from the incubation mixture is achieved by the use of a rabbit second step antiserum which confers high binding affinity for protein A to the primary immune complex. This method, as employed in the assay for human cathepsin B, is very reproducible and economical for large numbers of samples. The use of a monospecific antiserum to human cathepsin B and slightly alkaline assay conditions allow the determination of total cathepsin B protein in tissue fluids which is not possible by enzyme activity determination. | eng_Latn | 27,535 |
O6-substituted-2'-deoxyguanosine-3'-phosphate adducts detected by 32P past-labeling of styrene oxide treated DNA | Using two synthetic nucleotides we have shown that two of the adducts formed by the reaction of styrene oxide with DNA and detected by the 32 P post-labeling method correspond to aralkylation at the O 6 position of guanine | Abstract A method is described for extracting proteins and peptides from stained sodecyl sulfate-polyacrylamide gels. Coomassie blue and sodium dodecyl sulfate present in stained gel sections are removed to allow subsequent analysis of the peptides (e.g., amino acid analysis or tryptic digestion and fingerprinting). The method is simple, requires no radioisotopes or special equipment, and can be carried out with a minimum of handling of the sample. The process can be used for samples at the nanomole level with recoveries of 90%. | eng_Latn | 27,536 |
The Role of Hydroxide Ions in Reduction of Plutonyl Ion Stimulated by Nitrogen Laser Radiation (337.1 nm) | The behavior of the Pu22+ ion excited by radiation of a pulse nitrogen laser in aqueous solutions with a high content of CsF was studied at various pH. Chemiluminescence of luminol under the action of OH radicals arising in the solution was considered. The absorption spectra of PuO22+ complexes in aqueous solution with a high content of CsF are presented. | 2',3'-Cyclic nucleotide 3'-phosphohydrolase activity in the cerebrum of the inherited primary hypothyroid mouse (hyt/hyt) is reduced in comparison with the normal heterozygate (hyt/+). No differences were observed with regard to DNA and RNA content and the RNA/DNA ratio. The results of this study indicate that hypomyelination in the hypothyroid mouse is restricted to the cerebrum, and is not related to arrested glial proliferation. | eng_Latn | 27,537 |
Effects of different iodides on gold concentrates leaching process in iodine-iodide solution | Using the iodine-iodide leaching system,the effects of different iodides(ammonium iodide,potassium iodide, hydrogen iodide)on gold concentrates leaching process were discussed from the influence factors,such as initial iodine content,iodine and iodide ratio and solution pH value.The results show that,when ammonium iodide or potassium iodide is used as complex agent,under the conditions of initial iodine content of 1%,iodine and iodide molar ratio of 1:8, pH value of 7,liquid-solid ratio of 4:1,stirring speed of 600 r/min,leaching time of 4 h and temperature of 25 ℃,the gold leaching rates are around 90%;whereas the gold leaching effect is poorer when hydrogen iodide(aqueous solution is hydroiodic acid) is used as complex agent,and the gold leaching rate is only 75%.Considering the difference of leaching effect and availability of industry and so on,potassium iodide is the suitable complex reagent of gold concentrate leaching in iodine-iodide solution. | OBJECTIVE ::: To explore the change of tear immune function on eyeballs with perforating injury at high altitude. ::: ::: ::: METHODS ::: In 51 patients (53 eyes) with eyeball perforating injury at high altitude (sea level 3658 m), by using single agar immune diffusion test, IgG, IgA, IgM, C(3) and C(4) values of tears were separately measured before and after clinical cure. ::: ::: ::: RESULTS ::: The Ig values of tears increased universally. The IgA value increased especially in the 7th day. The IgG and IgM value in the serum increased in the 3rd day after injury (P < 0.05), and the IgG, IgA and IgM of tears increased especially on the 7th day (P < 0.01). The C(3) and C(4) value of tears did not change significantly (P < 0.05). ::: ::: ::: CONCLUSIONS ::: The change of Ig value is a useful detective means to evaluate the treatment effect. | eng_Latn | 27,538 |
Preparation and rearrangement of dialkyl and diaryl 1-methyl-1-(trichloromethyl)propyl phosphites | 1. ::: ::: In presence of triethylamine 1-methyl-1-(trichloromethyl)propyl phosphorodichloridite reacts with two molecular proportions of a primary or secondary alcohol or a phenol with formation of the corresponding mixed esters. Under these conditions chlorine-substituted tertiary alcohols can react with replacement of only one of the chlorine atoms of the phosphorodichloridous ester. ::: ::: ::: ::: ::: 2. ::: ::: Rearrangement of dialkyl 1-methyl-1-(trichloromethyl)propyl phosphites with allyl bromide goes with the elimination of the unsubstituted alkyl group and leads to the formation of mixed allylphosponic esters. | OBJECTIVE:To establish RP-HPLC method for the content determination of praeruptorin A in Qingfei yihuo pills.METHODS:The chromatographic column was Diamonsil-C18(250 mm×4.6 mm,5 μm) column.The mobile phase consisted of methanol-water(81:19) and the detection wavelength were set at 322 nm.RESULTS:The linear range of praeruptorin A was 4.65～23.25 μg·mL-1(r=0.999 9) with an average recovery of 100.5%(RSD=2.35%,n=6).CONCLUSION:The method is sensitive,well separated and accurate for content determination of Qingfei yihuo pills. | eng_Latn | 27,539 |
Time-resolved fluoroimunoassay of steroid hormones | Abstract The use of europium chelates as labels in immunoassays and their sensitive quantitation based on time-resolved fluorescence is reviewed. The technique is applied on competitive solid-phase immunoassays for direct determination of progesterone and estradiol in serum samples. Both antigen- and antibody-labelled competitive assays are described. The nonisotopic label technology, which provides a very high specific activity, as well as the antibody-labelled competitive assays, present several advantages in the assay of haptens as e.g. steroids. As the optimal sensitivity of competititive methods is not limited by the specific activity of the label the steroid assays which employ europium chelates as labels do not show any marked increase in sensitivity as compared to that achieved by using 125 I. The otential sensitivity provided by the high specific activity of the label is optimally utilized in noncompetitive immunometric assays. | Flow Injection (FI) techniques for use with Atomic Absorption Spectrometry (AAS) ::: have attracted considerable research interest for sample introduction and calibration ::: strategies. The interest continues in on-line preconcentration and matrix modification ::: which are carried out by the incorporation of liquid-liquid extraction, ion-exchange, ::: immobilised reagents, gas/vapour generation and continuous precipitation-filtration ::: devices into suitably designed manifolds. Indirect determination of inorganic anions and ::: organic compounds is becoming routine by FI–flame AAS. The direct analysis of solid ::: samples, which is a shortcoming of flame AAS, was recently carried out by on-line ::: electrolytic dissolutions. [Continues.] | eng_Latn | 27,540 |
Sustainable Recovery of Volatile Fatty Acids fromAqueous Solutions Using Terpenoids and Eutectic Solvents | Volatile fatty acids (VFAs) are produced in the anaerobic digestion of urban or food wastes and sewage sludge. The interest in these compounds has increased because of their use as platform chemicals. In this paper, the application of natural terpenoids and eutectic solvents to sustainably recover VFAs from aqueous solutions by extraction has been evaluated. First, a screening of solvents has been done using COSMO-RS, selecting three terpenoids: geraniol, citral, and eugenol, and two hydrophobic eutectic solvents formed by octanoic acid and menthol or thymol. These solvents have been tested in the extraction of acetic, propionic, butyric, and valeric acids. The highest yields were obtained using geraniol and the (octanoic acid + thymol) eutectic solvent, being comparable or higher than those for organic solvents from the literature. The back-extraction of the VFAs from both solvents has been studied using NaOH and Na2CO3 solutions, concluding that the eutectic solvent is not chemically stable to be reused... | Abstract Peptide and protein samples are often complex mixtures that contain a number of individual compounds. The initial HPLC separation of such samples typically results in the poor resolution of one or more band pairs. Various means have been suggested tor varying separation selectivity so as to minimize this problem. In this study of a tryptic digest of recombinant human growth hormone, the simultaneous variation of temperature and gradient steepness was found to be a convenient and effective means of varying selectivity and optimizing the separation. The use of computer simulation greatly facilitated this investigation. | eng_Latn | 27,541 |
An Analysis of Finite Element Approximation in Electrical Impedance Tomography | We present a finite element analysis of electrical impedance tomography for reconstructing the conductivity distribution from electrode voltage measurements by means of Tikhonov regularization. Two popular choices of the penalty term, i.e., $H^1(\Omega)$-norm smoothness penalty and total variation seminorm penalty, are considered. A piecewise linear finite element method is employed for discretizing the forward model, i.e., the complete electrode model, the conductivity, and the penalty functional. The convergence of the finite element approximations for the Tikhonov model on both polyhedral and smooth curved domains is established. This provides rigorous justifications for the ad hoc discretization procedures in the literature. | Artificial sweeteners are widely used in food, beverage and pharmaceutical industries all over the world. In this study some non-nutritive sweeteners such as aspartame, acesulfame-K, sodium cyclamate and sodium saccharin were simultaneously determined in ternary mixtures using FT-IR and EI-MS measurements. FT-IR method is based on direct measurements of the peak height values and area centered on 1736 cm−1, 836 cm−1, 2854 cm−1 and 1050 cm−1 for aspartame, acesulfame-K, sodium cyclamate and sodium saccharin, respectively. Mass spectrometry determinations show the characteristic peaks at m/z 91 and 262 for aspartame,m/z 43 and 163 acesulfame-K,m/z 83 and 97 for sodium cyclamate andm/z 104 and 183 for sodium saccharin. The results obtained by EI-MS in different formulations are in agreement with the FT-IR ones and provide also essential data concerning the purity grade of the components. It is concluded that FT-IR and EI-MS procedures developed in this work represent a fast, sensitive and low cost alternativ... | eng_Latn | 27,542 |
Content Determination of Praeruptorin A in Qingfei Yihuo Pills by RP-HPLC | OBJECTIVE:To establish RP-HPLC method for the content determination of praeruptorin A in Qingfei yihuo pills.METHODS:The chromatographic column was Diamonsil-C18(250 mm×4.6 mm,5 μm) column.The mobile phase consisted of methanol-water(81:19) and the detection wavelength were set at 322 nm.RESULTS:The linear range of praeruptorin A was 4.65～23.25 μg·mL-1(r=0.999 9) with an average recovery of 100.5%(RSD=2.35%,n=6).CONCLUSION:The method is sensitive,well separated and accurate for content determination of Qingfei yihuo pills. | The present invention relates to vectors useful for the administration of active principles (PA), preferably medicinal or nutritional, especially orally or parenterally. The technical problem solved by the invention is that consisting in the supply of vectors formed by (nano) or (micro) particles based on polyamino acids, and which are inert with respect to PA (proteins), of controllable granulometry, resistant and economical. The invention has an average particle size of less than 200 mum and consists of a polyamino acid of the Leu / Glu type, in which Leu / Glu + Leu> = 20% and Mw> = 10,000 D. | eng_Latn | 27,543 |
Thermospray and particle beam liquid chromatographic—mass spectrometric analysis of coumarin anticoagulants | Abstract Positive ion mass spectra were obtained from several coumarin oral anticoagulants (phenprocoumon, warfarin, acenocoumarol and dicoumarol) and derivatives by liquid chromatography—thermospray mass spectrometry (LC—TSP-MS) and liquid chromatography—electron impact mass spectrometry (LC—EI-MS) to assess the use of LC—MS methods for the determination of these compounds in biological materials. LC—TSP mass spectra showed a single [M + 1] + ion with no fragmentation; LC—EI mass spectra showed fragment ions which were similar in mass and relative intensities to those obtained by conventional EI-MS. These data should serve as a basis for the development of LC—MS methods for the qualitative and quantitative analysis of coumarin anticoagulants in biological samples. LC—TSP-MS was applied to the determination of phenprocoumon in a plasma extract from an anticoagulated patient. | Laser welding has become a very important method for industrial manufacturing. Despite of the inherent accuracy of laser welding, the resulting weld quality may still be affected by many dynamic conditions related to the operating parameters and to the properties of the welded material. Methods for monitoring the laser welding process are therefore needed to guarantee consistent manufacturing quality. In this paper, we present a method for characterizing spatters in laser welding of thick steel. Pre-processing and edge detection steps of the proposed algorithm are performed on-line with a very high speed by using a dedicated KOVA1 massively parallel image processing chip, and the actual characterization of the spatters is carried out off-line in Matlab. The methods proposed are simple and efficient, thus also facilitating possible integration of the whole algorithm for on-line processing. | eng_Latn | 27,544 |
Active Auxin Uptake by Specific Plasma Membrane Carriers | The directed movement of auxin plays a major regulatory role in the development of plants. The chemiosmotic hypothesis proposes that both cellular accumulation and polar transport of IAA (indole-3-acetic acid) are driven by transmembrane pH and electrical gradients [2, 13]. It has been proposed that a carrier(s) may be necessary to sustain reasonable rates of cell-to-cell transport and to provide the saturability, specificity, and polarity that are features of in vivo auxin transport through a variety of tissues [13,14]. These sites have been proposed to include both a saturable, specific IAA/proton uptake symport and a specific, perhaps electrogenic, anion efflux carrier, which can be blocked by specific, noncompetitive transport inhibitors, such as TIBA (2, 3, 5-triiodobenzoic acid). Hertel [4] has recently suggested that the efflux carrier is instead a symport with auxin leaving the cell as IAAH/H+. | The experiment was conducted to optimize the conditions of A-PAGE for isolating salt soluble proteins of foxtail millet.10 foxtail millet varieties were used for A-PAGE.A number of A-PAGE electropherograms were obtained at different levels of dosage of catalyst,gel concentrations,cross-linkages,injecting volumes,pH of gel buffer,and the use of inspissate gel.The optimal conditions for A-PAGE were raised after deliberate investigation.Detailed criteria were as following: dosage of 3% H2O2 1 μl/ml gel,gel concentration 13%,cross-linkages 4%,pH of gel buffer 3.7,and the injecting volumes between 20 and 30 μl.Furthermore,the use of inspissate gel enhanced the resolution of gel electropherograms. | eng_Latn | 27,545 |
186 Rhenium isolation method and apparatus | The isolation method of The vaporized source compound ionized and the molecule negatively charged including Separating the molecules bearing a negative charge, to isolate molecules that negatively charged including The molecules bearing a negative charge comprising an isolated As a result, it is possible to use an isolated | Abstract We report the application of a sandwich technique in flow injection systems which afford low consumption of expensive reagents and two reagent recirculation systems. The potential applicability of the technique thus developed was assessed by determining glucose in serum samples by the enzymatic glucosidase/peroxidase method. It was possible to perform up to 450 determinations with the same amount of reagent used to perform 50 determinations by batch procedures. The sampling rate was 80 determinations per hour with a 0.9% relative standard deviation. | eng_Latn | 27,546 |
The influence of embedding media and fixation on the postembedment ultrastructural demonstration of complex carbohydrates. III. High iron diamine staining for sulfated glycoconjugates. | The high iron diamine (HID) method for detection of sulfated complex carbohydrate has been applied directly on thin sections of variably fixed tissues embedded in epoxy and nonepoxy resins. Results with postembedment HID staining in mouse intestinal epithelium are compared to those previously obtained using preembedment methods. Sections from epoxy-embedded tissues have been found to exhibit the weakest staining intensity. Intense, specific staining was obtained in tissues not postfixed with osmium tetroxide and embedded in polystyrene, polyester resins, styrene-methacrylate, and especially the styrene-Vestopal W embedding mixture. Postosmication of tissues abolished HID staining in epoxy resins and the styrene-Spurr's resin embedding mixture, but only reduced the staining intensity in tissues embedded in nonepoxy resins. | Coloring reaction of sake caused by exposure to sun-light was investigated. There is one of the coloring reactions in which deferri-ferrichrysin participate. The reaction was named Reaction I.Deferri-ferrichrysin, tyrosine, Mn2+ and unknown nitrogenous compound named conveniently compound X were essential for Reaction I and citric acid was stimulative.Compound X was purified by using Amberlite IR 120 (H type) column, active carbon column, silicic acid column and alumina column, and crystallized from methanol-water (1 : 1).The crystals decomposed at 288~290°C. The ultraviolet and infrared spectra of the compound X were essentially identical with those of authentic kynurenic acid.From these results the compound X was identified as kynurenic acid.Since kynurenic acid alone did not cause the color development and riboflavin could be substituted for kynurenic acid in Reaction I, kynurenic acid may act as photosensitizer in Reaction I. | eng_Latn | 27,547 |
가상 HC 센서를 이용한 Evaporative System Monitoring 방법에 대한 연구 | This paper presents a new evaporative system monitoring method using a virtual HC sensor for an automotive on-board diagnosis. A development was made at providing mathematical expressions from the lambda control information to estimate the HC mass 리ow purged into the intake manifold from the canister for implementing a virtual HC sensor. The change or the lambda averagevalue reflected the influence or the additional fuel from purging results the sensor estimation of the purged HC amount. Based on this virtual HC sensor, a new evaporative system monitoring method was proposed comparing the amount of purged HC amount with the amount or the HC gas evaporated from the fuel tank and absorbed into the canister. Finally, the method was validated with a simulation using the data logged from the retail car. | Abstract Positive ion mass spectra were obtained from several coumarin oral anticoagulants (phenprocoumon, warfarin, acenocoumarol and dicoumarol) and derivatives by liquid chromatography—thermospray mass spectrometry (LC—TSP-MS) and liquid chromatography—electron impact mass spectrometry (LC—EI-MS) to assess the use of LC—MS methods for the determination of these compounds in biological materials. LC—TSP mass spectra showed a single [M + 1] + ion with no fragmentation; LC—EI mass spectra showed fragment ions which were similar in mass and relative intensities to those obtained by conventional EI-MS. These data should serve as a basis for the development of LC—MS methods for the qualitative and quantitative analysis of coumarin anticoagulants in biological samples. LC—TSP-MS was applied to the determination of phenprocoumon in a plasma extract from an anticoagulated patient. | kor_Hang | 27,548 |
Giving anemia a boost with inhibitors of prolyl hydroxylase. | There is much current interest in the development of inhibitors of the prolyl hydroxylase (PHD) enzymes that regulate the hypoxia-inducible transcription factor (HIF), which in turn stimulates the production of erythropoietin and ultimately red blood cells, as a treatment for anemia. A recent paper reports the synthesis and evaluation of a novel class of potent spirohydantoin-based pan-PHD inhibitors for this purpose. The paper is an exemplar of drug development from high-throughput screen to clinical candidate. | Abstract Human peripheral blood lymphocytes in culture rarely undergo division or exhibit a demonstrable synthesis of DNA in the absence of a mitogenic stimulus (Nowell, 1960) . The incorporation of precursors into RNA occurs at a low level in normal lymphocytes and upon addition of phytohemagglutinin (PHA), a marked stimulation is observed (Rubin and Cooper, 1965) . In order that this process may be studied in detail, a system is described in this communication for the synthesis of RNA (Weiss, 1960) in lymphocyte nuclei obtained from cells not exposed to PHA. In addition to nuclei, the system requires magnesium ion, the four common ribonucleoside triphosphates and ammonium sulfate for maximal activity. Furthermore, utilization of the DNA template for RNA synthesis is prevented by the addition of DNAase, Actinomycin D and RNAase. The incorporation of ribonucleoside triphosphate into RNA proceeds for a relatively long period of time (2 hours) and the product formed is stable under the conditions employed. | eng_Latn | 27,549 |
High-performance liquid chromatography analysis of the thiobarbituric acid adducts of malonaldehyde and trans,trans-muconaldehyde. | A reversed-phase HPLC method is described for the separation and analysis of the thiobarbituric acid (TBA) adducts of the reactive aldehydes muconaldehyde (MUC) and malonaldehyde (MDA). The TBA adduct of malonaldehyde was synthesized, purified, and its structure elucidated, for use as standard in quantitative HPLC studies. A detection limit of 1 X 10(-14) mol was achieved for the MUC:TBA and MDA:TBA adducts using the double monochromator fluorometric detector, 7 X 10(-13) mol was the detection limit using a variable wavelength uv-visible detector. Direct on-line identification of the eluting aldehyde:TBA adducts was achieved by the use of a diode-array uv-visible detector. The chromatographic behavior of the adducts under different mobile phase conditions was also examined. This HPLC methodology was used for the identification of muconaldehyde as a product of benzene oxidation in a hydroxyl radical generating system. | Diethylpyrocarbonate treatment of the neutral endopeptidase (EC 3.4.24.11) inhibits both catalytic activity and binding of the inhibitor [3H]-N(R,S)-3-hydroxyaminocarbonyl-2-benzyl-1-oxopropyl]-glycine. The loss of activity can be reversed by hydroxylamine and almost completely prevented by the competitive inhibitor phenylalanyl-leucine suggesting the presence, as in thermolysin, of a histidine residue at the active site. Butanedione treatment also reduces both catalytic activity and [3H] inhibitor binding. Phenylalanyl-leucine completely protects from the butanedione induced loss of activity, providing further evidence for an essential arginine at the active site. In contrast, the tyrosine modifying agent N-acetylimidazole has no apparent effect on enzyme activity. | eng_Latn | 27,550 |
Effects of low doses of alpha chlorohydrin on the dehydrogenases and oxidases of rat epididymal epithelium and sperms: a correlative histochemical and biochemical study. | Histochemical studies have been made of the isocitrate dehydrogenase, succinic dehydrogenase, malate dehydrogenase, glutamate dehydrogenase, DPN diaphorase, TPN diaphorase, delta 5-3 beta-hydroxysteroid dehydrogenase and monoamine oxidase in the caput, corpus and cauda epididymides of normal and alpha chlorohydrin (6.5 mg/kg/9 days) treated rats. Administration of alpha chlorohydrin in a low dose caused a conspicuous decrease in all these enzymes except delta 5-3 beta-HSD, in various cell types of epididymal epithelium and sperms. Biochemical estimations of isocitrate dehydrogenase, succinic dehydrogenase, malate dehydrogenase and delta 5-3 beta-HSD have further supported and confirmed these histochemical observations. These changes in enzyme activities after treatment with low dose of alpha chlorohydrin strongly suggest that TCA cycle and amino acid metabolism of epididymis become defective, much earlier before any histological damage to the epididymis becomes visible. | Our recent nanoindentation measurements on phage lambda, revealed an evolutionary optimization of DNA density in viral capsid. Based on these experimental data, we proposed that water hydrating DNA in the capsid, provides significant support against external capsid deformation at wild-type DNA packing density. Shorter DNA length mutants are on the other hand two times weaker just like empty capsids. In this work, we perform a stringent test of this assumption. DNA hydration force can be dramatically decreased by addition of multivalent ions (here Mg2+ and Sp4+). Indeed, AFM measurements demonstrate that spring constant for wt-DNA phage lambda decreases to a value of an empty capsid upon addition of multivalent salt compared to the “zero-added-salt” value obtained in the previous work. This data is systematically analyzed with DNA hydration model and further comparison is made with phage fi29. | eng_Latn | 27,551 |
Enantioselective Total Synthesis of (+)-Taxusin | For the total synthesis of (+)-taxusin, the AC-ring fragment 8 was prepared from an optically active 2-bromo-3-siloxycyclohexenecarbacetal 5 via 4 steps and was converted to the dienol silyl ether 13. The thus-obtained 13 underwent B-ring cyclization in the presence of Me2AlOTf to produce the ABC endo-tricarbocycle 14 having C9α, C10β-substituents, which was converted to the cyclopropyl ketone 21a. Introduction of C19 methyl via reductive cleavage of the cyclopropane ring under Birch conditions and successive in situ treatment of the resulting enol with methanol gave the C3α-protonated ketone 24. Next, 24 was converted to the allylsilane 29, which was then oxidized with m-CPBA to produce the fully functionalized taxusin carbon skeleton. Finally, removal of the silyl protecting groups followed by acetylation completed the total synthesis of (+)-taxusin. | SummaryA baby hamster kidney cell line transformed in vitro by adenovirus type 12 produced high titer T antigen. Using different tumor-bearing hamster sera in the indirect fluorescent antibody technic the resultant staining was either confined to the cytoplasm or was present also in the nucleus. Both the intranuclear T antigen and intracytoplasmic T antigen when isolated behaved similarly on hydroxylapatite columns and on starch block electrophoresis. On hydroxylapatite columns the majority of the recovered CF activity was eluted with 0.2 M salt. On starch block electrophoresis all of the recovered CF activity was present in one peak effecting a 10-fold increase in specific activity by a one-step procedure. Preparations with highest specific activity were obtained from fractions of nuclear preparations separated by starch block electrophoresis.The excellent technical assistance of Mrs. Jessie Doleman, Miss Shirley J. Hagens, Mrs. Beatrice R. O'Keefe and Mrs. Inta Ziedins is gratefully acknowledged. | ast_Latn | 27,552 |
Importance of Aromatic Content for Peptide/Single-Walled Carbon Nanotube Interactions | We have previously demonstrated that a designed amphiphilic peptide helix, denoted nano-1, coats and debundles single-walled carbon nanotubes (SWNTs) and promotes the assembly of these coated SWNTs into novel hierarchical structures via peptide−peptide interactions. The purpose of this study is to better understand how aromatic content impacts interactions between peptides and SWNTs. We have designed a series of peptides, based on the nano-1 sequence, in which the aromatic content is systematically varied. Atomic force microscopy measurements and optical absorption spectroscopy reveal that the ability to disperse individual SWNTs increases with increasing aromatic residues in the peptide. Altogether, the results indicate that π-stacking interactions play an important role in peptide dispersion of SWNTs. | Abstract The use of europium chelates as labels in immunoassays and their sensitive quantitation based on time-resolved fluorescence is reviewed. The technique is applied on competitive solid-phase immunoassays for direct determination of progesterone and estradiol in serum samples. Both antigen- and antibody-labelled competitive assays are described. The nonisotopic label technology, which provides a very high specific activity, as well as the antibody-labelled competitive assays, present several advantages in the assay of haptens as e.g. steroids. As the optimal sensitivity of competititive methods is not limited by the specific activity of the label the steroid assays which employ europium chelates as labels do not show any marked increase in sensitivity as compared to that achieved by using 125 I. The otential sensitivity provided by the high specific activity of the label is optimally utilized in noncompetitive immunometric assays. | eng_Latn | 27,553 |
Serum magnesium levels in patients treated with phenytoin | Abstract Phenytoin and magnesium levels were measured in eighty epileptics and seventy-one control subjects in an investigation into possible effects of phenytoin on serum magnesium levels. Phenytoin levels were measured using GLC and magnesium levels by atomic absorption spectrophotometry. The study showed no significant effect of phenytoin on serum magnesium concentration. | Objective:To determine the optimized conditions for PCR amplification of DNA with rich GC in order to freely assemble modules or domains of polyketide synthase (PKS) in macrolide combinatorial biosynthesis.Methods:Formamide, glycerol, DMSO and Mg 2+ were added to the PCR amplification system and amplification system was chosen to optimize the conditions for PCR amplification of DNA with rich GC.Results:Formamide had no influence on PCR amplification of DNA with rich GC, while both glycerol and DMSO promoted output and specificity of PCR product, with 5%-10% DMSO showing the best effectiveness. When Roche Expand Long Template PCR System was used and 10% DMSO and extra 0.25?mmol/L Mg 2+ were added to buffer 2, 5?kb DNA with 73% GC content was amplified.Conclusion:With addition of DMSO and extra Mg 2+ to PCR system, at least 5?kb DNA with rich GC could be amplified, and that can meet the need to assemble any modules or domains in macrolide combinatorial biosynthesis. | eng_Latn | 27,554 |
Cu-Pybox catalyzed synthesis of 2,3-disubstituted imidazo[1,2-a]pyridines from 2-aminopyridines and propargyl alcohol derivatives | Abstract A highly efficient cascade sequence for syntheses of 2,3-disubstituted imidazo[1,2-a]pyridines with exclusive regioselectivity in moderate to excellent yields has been developed. This cascade was initiated through propargylation of 2-aminopyridines at pyridine-nitrogen with propargyl alcohol derivatives using Cu(II)-Pybox as catalyst and followed by an intramolecular cyclization and isomerization. Besides 2-aminopyridine, less reactive 2-aminopyrimidine, 2-aminopyrazine and 3-aminopyridazine were also suitable in this cascade. | 1. 4-Cyano-N, N-dimethylaniline (CDA), when administered to rats as a single oral dose (18.5 mg/kg), was rapidly absorbed and eliminated as a mixture of metabolites in the urine (86% dose after 24 h).2. Residues in tissues after 48 h, expressed as μg equiv. of CDA, were: liver, 0.35; kidney, 0.28; testes, 0-08; fat, 006; bone marrow, 0.15 and blood, 0.32.3. Absorption, metabolism and elimination following four consecutive daily doses of CDA (65 mg/kg) were similar to those at the lower dose.4. The major metabolite was 2-amino-5-cyanophenyl sulphate with its mono- and di-N-methyl analogues as minor metabolites. 4-Cyanoaniline, its N-acetyl derivative and an unstable derivative were also found as metabolites.5. Three sulphur-containing metabolites with methylsulphinyl-, methylsulphonyl-, and N-acetylcysteinyl-groups attached to the C2 atom of an N-acetyl group were identified, the latter accounting for 10.3% and 41% of the low and high doses, respectively.6. The sulphur-containing metabolites indicate the i... | eng_Latn | 27,555 |
Development of an electrochemical biosensor for vitamin B12 using D-phenylalanine nanotubes | In the past decades, biosensors are one of the most interesting topics among researchers and scientist. The biosensors are used in several applications such as determining food quality, control and diagnose clinical problems and metabolic control. Therefore, many efforts have been carried out to design and develop a new generation of these systems. On the other hand nanotechnology by improving the performance of sensors has created an excellent outlook. Using nanomaterials such as nanoparticles, nanotubes, nanowires, and nanorods in diagnostic tools has been significantly increased accuracy, sensitivity and improved detection limits in sensors. In this study, the one-dimensional morphology of the D-phenylalanine was assembled on the surface of the gold electrode. In the next step electrochemical performance of the modified electrode was investigated by Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and Differential Pals Voltammograms (DPV). Finally, by measuring the different concen... | A healthy tissue tolerance study1,2 with Beagle dogs was carried out at the Finnish BNCT facility FiR 1 during February-March 1998. Three dose groups of dogs without boron carrier, each comprising five Beagles, and one dose group with BPA-F infusion were irradiated. Individual dose plans1 were done for each dog. The absorbed doses, which were actually delivered to healthy tissues, were monitored in vivo by placing the dosimeters on the shaved skin of the dogs or in the accessible cavities. In this study, absorbed gamma doses were monitored with thermoluminescent (TL) dosimeters, and neutron fluences were determined with activation foils. The obtained results were compared to the calculated values. | eng_Latn | 27,556 |
Are amines basic or nucleophilic catalysts for oxirane ring opening by proton-donating nucleophiles? | The behavior of amines as catalysts for oxirane acidolysis and phenolysis has been studied using kinetic methods. The apparent catalytic and noncatalytic reaction rate constants have been estimated. It has been demonstrated that the noncatalytic pathway has almost no effect on the apparent reaction rate constant. In order to determine the character of the behavior of amines (bases/nucleophiles) in this reaction, their reactivity has been analyzed within the conceptions of basic and nucleophilic mechanisms of catalysis. Based on the quantitative amine structure—catalytic activity correlation, it has been shown by comparing the values of correlation coefficients (r) of equations describing mechanisms for various reaction systems that, in the reactions of oxiranes with proton donors (carboxylic acids and phenols), the catalytic activity of tertiary amines/pyridines is determined by their nucleophilicity rather than basicity. | When uredospores of wheat stem rust, Puccinia graminis van tritici (race 15B), were incubated with a 3 mM solution of ammonium chloride-15N, a significant amount of nitrogen 15 was converted into organic nitrogen. Most of this organic nitrogen 15 was found in the ethanol and water extracts, with lesser amounts in the buffer and in extracted spores.Amino acids extracted from the spores all contained excess nitrogen 15. Nitrogen 15 from the inorganic source was diluted by factors of 1.7 and 2.7 in free aspartic and glutamic acids respectively; these amino acids were the most heavily labeled with the isotope. Proline was the most weakly labeled amino acid, the nitrogen 15 being diluted by a factor of 102. Good incorporation of nitrogen 15 into glutamic acid compared to simultaneous poor incorporation into the biochemically related amino acid, proline, parallels previous observations made during carbon 14 experiments with rust uredospores.Fourteen "bound" amino acids were isolated after acid hydrolysis of ext... | eng_Latn | 27,557 |
Preparation and characterization of a pyrethrum extract standard | The authors separated and collected milligram quantities of six pyrethrin esters in pyrethrum extract by semipreparative, normal-phase high performance liquid chromatography (HPLC). They structurally confirmed each ester by Fourier transform-infrared spectroscopy and gas chromatography-mass spectrometry. They also checked retention times based upon previously developed HPLC methodology. They determined the purity of each ester based upon the chromatographic area percentage. The authors then used the esters as individual standards to restandardize the content of pyrethrin esters in two selected pyrethrum extracts, which they previously had assayed using the Association of Official Analytical Chemists International titration method. They will submit one of the selected pyrethrum extracts to the U.S. Pharmacopoeia as a potential reference standard for additional applications. | For a large class of vanilla contingent claims, we establish an explicit F\"ollmer-Schweizer decomposition when the underlying is a process with independent increments (PII) and an exponential of a PII process. This allows to provide an efficient algorithm for solving the mean variance hedging problem. Applications to models derived from the electricity market are performed. | eng_Latn | 27,558 |
Radioprotective efficacy of synthetic porphyrins in experiments on cell cultures | The effects of several synthetic and semisynthetic porphyrins on the stimulation of postradiation survival of cell cultures were studied. Asynchronous cultures of monkey heart cells were used in the investigation. | [Objective]To establish a method for determination of phosphorus in foods by microwave ashing and molecular absorption spectrometry.[Methods]The samples were incinerated by microwave ashing method,and the determination results were compared with that of GB method.[Results]According to precision test,RSD was 1.5%.Recovery rate was 90.0%～95.8%.There was no significant different in the determination results between microwave ashing method and GB method.[Conclusion]The microwave ashing method for determination of phosphorus in foods has high accuracy and good reproducibility,which is worth popularizing. | eng_Latn | 27,559 |
Application of Chelate of Amino Acid Chelated Trace Element in Livestock and Poutry Nutrition | Amino acid chelated trace element is a new type of green feed additives, can solve the low rate of trace element absorption and excessive add trace elements in environmental pollution problems, when used in live stock and poultry feed. Its development history, nutrition physiological function and problems in production were in troduced in this article. | Methionyl tRNA acylated within mitochondria isolated from mouse liver, has been resolved into four species by RPC-5 chromatography. All four elute prior to the three cytoplasmic methionyl tRNA species. Of the four species, two are formylated. These results suggest that iso-accepting species of met-tRNAmet exist in mouse liver mitochondria. | eng_Latn | 27,560 |
Experimental study on effects of component from Centella asiatica on compound TLR4 in mice tubular epithelial cells stimulated by tumor necrosis factor α | AIM:To investigate the effects of component from Centella asiatica(centella asiatica emodin)on toll like receptor 4(TLR4)mRNA and protein in mice tubular epithelial cells(mTEC)stimulated by tumor necrosis factor α(TNF-α).METHODS:Cultured mTEC were exposed to TNF-α 5 ng/mL and centella asiatica emodin for 24 hours,followed by transcriptase-polymerase chain reaction(RT-PCR)and enzyme-linked flow cytometry(FCM)analysis for complement TLR4 mRNA and protein expression.RESULTS:TLR4 mRNA and protein production were present in mTEC.TNF-α up-regulated TLR4 production in mTEC.Centella asiatica combined with emodin synergistically down-regulate TLR4 expression at a dose of 4 μg/mL and 0.4 μg/mL.CONCLUSION:Effective component from Centella asiatica component induced TLR4 stimulated by TNF-α in source of kidney local. | Factors that affect ISSR PCR amplification,such as Mg2+ concentration,dNTP concentration,were optimized by using the genomic DNA of a rare and endangered species Rhododendron shanii as material,on the foundation of optimization,8 primers were selected.The optimal annealing temperature of every primer was selected by using gradient PCR instrument.The optimized result indicates that at least in certain scope template DNA dosage and Taq DNA polymerase affect little on the result of PCR reaction,relatively,Mg2+ concentration and dNTP concentration have significant effects to the result.The suitable 15ul PCR reaction should contain 20ng template DNA,0.3μM primer,1.5ul buffer(Mg2+ free),0.5U Taq DNA polymerase,1.5 mM MgCl2 and 0.1 mM dNTP. | eng_Latn | 27,561 |
Standardization of a colorimetric method for the determination of fructose using o-cresol: Sulphuric acid reagent | Fructose developed a pinkish orange chromogen on treatment with o-cresol: 70% sulphuric acid at 32°C for 15 minutes with a λ max of 500nm. Fructose was 185 times more chromogenic than glucose. Total carbohydrate and fructose values in protein-free filtrate of normal serum samples were in the range, 55.4–86.3 mg/dl and 1.55–3.29 mg/dl, respectively. In diabetes, the observed values were 197–354 mg/dl and 2.91–6.81 mg/dl, respectively. | Abstract The discovery of a new isomer of the endohedral metallofullerene Sc 3 N@C 80 is reported. 13 C labeled (∼9%) Sc 3 N@C 80 has been synthesized and has been characterized by HPLC, mass spectroscopy and 13 C NMR data. The 13 C NMR spectrum shows six peaks with a 1:2:2:1:1:1 ratio that are assigned to the D 5h isomer. The results of theoretical calculations are also reported for the I h and D 5h isomers of Sc 3 N@C 80 . | eng_Latn | 27,562 |
Differential thermal analysis of Ag–Ge–Se, Ge–Se charge materials in the process of their heating and Ag8GeSe6, GeSe2 compound synthesis | Abstract This is the first comprehensive study of the processes of phase transformations (PT) and chemical reactions (CR) that accompany Ge–Se and Ag–Ge–Se charge material heating in stoichiometric proportions corresponding to GeSe 2 compounds, Ag 8 GeSe 6 argyrodite and elementary selenium. The investigation was carried out by means of the differential thermal analysis (DTA) method. The PT in selenium and the main types of PT and CR of the formation of GeSe 2 , Ag 8 GeSe 6 compounds have been identified. The characteristic heats and temperature ranges of reaction processes have been determined. Ag 8 GeSe 6 and GeSe 2 compounds formation has been experimentally demonstrated due to the DTA and X-ray analysis. | A radiochemical method for the 18F-glycosylation of amino acid side chains was developed starting from peracetylated 2-deoxy-2-[18F]fluoroglucopyranoside (TA-[18F]FDG). O-(2-deoxy-2-[18F]fluoro-D-glucopyranosyl)-L-serine and the corresponding threonyl compound were obtained in a radiochemical yield of 25% and 12% (related to [18F]fluoride), respectively, after Zemplen deprotection within a total reaction time of 90 min. The anomeric configuration of the corresponding 19F-substituted compounds revealed preferential α-stereoselectivity. The 18F-glycosylation method using TA-[18F]FDG is compatible with the short half-life of fluorine-18 and combines glycosylation and 18F-labelling of a target compound within a single reaction step. TA-[18F]FDG is a promising 18F-labelled prosthetic group and could be adapted to 18F-labelling of bioactive peptides to study their pharmacokinetics using positron emission tomography (PET). Copyright © 2005 John Wiley & Sons, Ltd. | eng_Latn | 27,563 |
Comparative evaluation of Nabi and Beltsville extenders for cryopreservation of rooster semen | Abstract Two experiments were conducted to evaluate the new rooster semen freezing extender which is containing a low level of glycerol and soybean lecithin as an alternative protective agent in the extender. The aim of the first experiment was to evaluate a new extender for freeze-thawing rooster semen known as “Nabi” extender compared to Beltsville. Second experiment was also performed to determine whether the Nabi extender has negative reactions on fertilization after artificial insemination (AI) or no. In the first experiment, post-thaw motion parameters, mitochondrial function and sperm apoptosis were analyzed using Sperm Class Analyzer (SCA), rhodamine-123 and Annexin-V, respectively for frozen-thawed semen in Nabi and Beltsville extender. Results showed that total motility, progressive motility, velocity parameters (VCL, VSL, VAP, LIN and STR) and live spermatozoa with active mitochondria were significantly higher in Nabi compare to Beltsville extender (P | BACKGROUND ::: The National Health and Nutrition Examination Survey's 9NHANES) biospecimena program was formed to manage the collection of biospecimena (including serum, plasma, urine, and DNA) from NHANES cycles, the storage of biospecimens in NHANES biospecimens, accessing of biospecimens by researchers and the providing of resulting data to future researchers. Data from biospeceimen research can be combined with existing NHANES data. ::: ::: ::: OBJECTIVE ::: This report provides background on the development of NHANES biorepositories and describes the collection, processing, and storing of biospecimens; ethical considerations and informed consent; and the proposal process for accessing biospecimens and resulting data. The number and types of biospecimens collected in each survey cycle from NHANES III (1988- 1994) through NHANES 1999-2014 are discussed so that researchers can understand what biospecimens are available if they are considering using NHANES biospecimens in their research. | eng_Latn | 27,564 |
Applications of mass spectrometry-based targeted and non-targeted lipidomics. | Recent advances in mass spectrometry have expanded our knowledge of lipids and lipid metabolic pathways involved in many (patho)physiological events. Targeted and non-targeted lipidomics are powerful analytical strategies with distinct features, and a combination of these two approaches is often employed to maximize the coverage of lipid species detected and quantified in complex biological matrices. This review briefly summarizes the applications of targeted and non-targeted lipidomics, mainly focusing on electrospray ionization-liquid chromatography-tandem mass spectrometry (ESI-LC-MS/MS), along with recent technical advances in the field. Current limitations and challenges in lipidomics and possible solutions are also discussed. | In an earlier paper by the author the problem of determining the optimum symmetrical weighting factors for a video MTI radar was discussed. This paper extends this work so as to remove the symmetrical restriction from the problem. In addition, for a staggered pulse system, optimum times of transmission are determined. In the earlier paper a global solution to the restricted optimization problem was achieved. In this paper only a locally optimum solution is achieved for the more general problem. | eng_Latn | 27,565 |
Novel method for SEI based on 3D-Hilbert energy spectrum and multi-scale segmentation features | This paper proposes a novel specific emitter identification (SEI) method for communication emitter individual identification based on the 3D-Hilbert energy spectrum and multi-scales segmentation (3D-HESMS). First, the time-frequency energy spectrum is derived via Hilbert-Huang Transform (HHT), which can be defined as a complicated curved surface in the three dimension space, namely the 3D-HUbert energy spectrum. Then, via the fractal theory, four features are extracted to compose the feature vector under multi-scale segmentation. Finally, the communication emitter individual identification is achieved utilizing the Support Vector Machine (S VM). Moreover, the identification performance of the 3D-HESMS method is compared with two existing methods. The experiment results show that the identification rate of the 3D-HESMS method is higher than that of the other two methods. The features extracted by the 3D-HESMS method have a high stability, sufficiency, and identifiability. | Abstract A computer-controlled mass spectrometric (MS) analysis of urine, blood and gastric aspirate from 21 drug overdose patients and urine from 15 heroin/morphine addicts, using a direct sample extract introduction into the MS via a membrane separator, is described. The Llewellyn 3 stage membrane separator inlet system allows rapid mass spectrometric analysis, eliminating time-consuming gas chromatographic separation or derivatization of the sample. A computer is used to identify the drugs or drug metabolites according to their fractionation pattern. Normal body fluid components do not interfere significantly. The sensitivity limit of the system is 0.5 mg/100 ml. The total analysis time including the sample work-up is 10 min. | eng_Latn | 27,566 |
FORMULATION OF ANTIOXIDANT LOTION CONTAINING WATER EXTRACT OF GREEN TEA LEAF (Camellia sinensis L) | The research about lotion dosage formulation that contain green tea leaf water extract with concentration 0.0002%, 0.002%, 0,02%, and 8.6% had been done. The basic of the EC 50 value. Which calculated from linierity regression equation between tested solution concentration and scavenging percent. The lotion formulation began with lotion base orientation included organoleptic, homogeinity, pH, and viscosity. It showed that lotion base with glyceryl monostearate 5.5% have the best pH stability, viscosity, and consistency. Evaluation of lotion dosage include physical evaluation (organoleptic, homogeinity, viscosity and stability) and chemical evalution (pH and the stability of lotion antioxidant activity. Antioxidant activity stability evaluation of lotion with 1,1-diphenyl-2-picrylhidrazyl solution using spectrophotometri UV-Visible showed, that formula which contain 0.02% and 8.6% green tea leaf water extract gave the best radical scavenging activity and stable during storage. | Chemical components of Fufang Suan-Zao-Ren-Tang decoction and their metabolites in rats were identified by HPLC-ESI-MS.Samples were separated by a Zorbax C18 column using a binary gradient elution,and analyzed by HPLC-ESI-MS.The ions of compounds in negative modes were observed for molecule mass information,and the potential structures were identified by attentive studying on the mass spectra of compounds and comparing with reference data and some of standards.It is the first time to establish an analysis method using HPLC-MC to identify the chemical and metalobic components of Fufang Suan-Zao-Ren-Tang decoction.Further research about Suan-Zao-Ren-Tang decoction can base on this analysis method. | yue_Hant | 27,567 |
Étude par transformation de Fourier de CH 3 Br et CH 3 Cl dans l’infrarouge très lointain | A high resolution Fourier transform spectrometer has been constructed for working in the far infrared region. After a description of this instrument, its performance in the 10–40 cm−1 spectral region is demonstrated by studying the pure rotational spectra of CH3Cl and CH3Br. A working resolution of 0.05 cm−1 is verified, and isotopic splitting is observed in CH3Br out to 14 cm−1. | FTIR spectroscopy in combination with multivariate calibrations, i.e. partial least square (PLS) and ::: principle component regression (PCR) was developed for quantitative analysis of cod liver oil (CLO) in binary ::: mixture with corn oil (CO). The spectra of CLO, CO and their blends with certain concentrations were scanned ::: using horizontal attenuated total reflectance (HATR) accessory at mid infrared (MIR) region of 4,000 – 650 ::: cm-1. The optimal spectral treatments selected for calibration models were based on its ability to provide the ::: highest values of coefficient of determination (R2 ::: ) and the lowest values of root mean error of calibration ::: (RMSEC). PLS was slightly well suited for quantitative analysis of CLO compared to PCR. FTIR spectroscopy ::: in combination with multivariate calibration offers rapid, no excessive chemical reagent, and easy in operational ::: to be applied for determination of CLO in binary mixture with other oils. | fra_Latn | 27,568 |
Discovery of N-(2-aminoethyl)-N-benzyloxyphenyl benzamides: New potent Trypanosoma brucei inhibitors. | A phenotypic screen of a compound library for antiparasitic activity on Trypanosoma brucei, the causative agent of Human African Trypanosomiasis (HAT), led to the identification of N-(2-aminoethyl)-N-phenyl benzamides as a starting point for hit-to-lead medicinal chemistry. Eighty two analogues were prepared, which led to the identification of a set of highly potent N-(2-aminoethyl)-N-benzyloxyphenyl benzamides with the most potent compound 73 having an in vitro EC50=0.001μM. The compounds displayed drug-like properties when tested in a number of in vitro assays. Compound 73 was orally bioavailable and displayed good plasma and brain exposure in mice, cured 2 out of 3 mice infected with Trypanosoma brucei in acute model when dosed orally at 50mg/kg once per day for 4days. Given its potent antiparasitic properties and its ease of synthesis, compound 73 represents a potential lead for the development of drug to treat Human African Trypanosomiasis. | OBJECTIVE To establish a method for the test of bacterial endotoxins in order to replace the test for pyrogen in Shengmai injection. METHODS The inhibition and enhancement test were carried out by tachypleus amebocyte lysate ES-Test according to the bacteria endotoxin content by Chinese Pharmacopoeia (2000). RESULTS The bacterial endotoxins limit value of Shengmai injection was 3.75EU/mL and the experiment showed that the interference elements could be excluded by diluting Shengmai injection 10 times. CONCLUSION The method is convenient,sensitive,accurate and can replaces the pyrogen test of Shengmai injection. | eng_Latn | 27,569 |
Contributions to silica gel application in residue analysis: V. Simple micro method for liquid chromatographic separation of chlorinated hydrocarbon pesticides and polychlorinated Biphenyls (PCB's) | A simple micromethod for the determination of organochloride pesticides and polychlorinated biphenyls (PCB's) is discussed. Using 2 g, 3 g and 4 g silica gel columns, the pesticides are quantitatively eluated with 20 ml, 25 ml and 30 ml of solvent, retaining 90 mg, 140 mg and 190 mg of fat. Recoveries of pesticides ranged from 90–100%. | The establishment of reliable serological methods for cysticercosis in pigs is important for the surveillance, control and prevention of taeniosis/cysticercosis in humans as well as in pigs to prevent economic loss. Both ELISA and immunoblot using glycoproteins (GPs) purified by a single step of preparative iso-electric focusing, which are highly useful for human cysticercosis, have been applied for a serological study in pigs naturally infected with Taenia solium . All sera from pigs showed similar responses to those in human cysticercosis. Therefore, it is expected that both ELISA and immunoblots using GPs would be useful in differentiating infected pigs from uninfected ones. | eng_Latn | 27,570 |
1-(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)-3-thioureidothiourea monohydrate | In the title compound, C16H24N4O9S2·H2O, the hexopyranosyl ring adopts a chair conformation (4C1), and the five substituents are in equatorial positions. In the crystal structure, extensive O—H⋯O, N—H⋯S and N—H⋯O hydrogen bonding leads to the formation of a three-dimensional network. | The toxic solution used at the Tokyo Subway Sarin Incident was purified by vacuum distillation. We were thus able to obtain sarin with high purity. We conducted a quantitative analysis of sarin using 31P-NMR spectrometry. High-purity sarin was examined by trimethyl phosphate as an internal standard. In comparison with 1H nondecoupling, the relative intensity between sarin and the internal standard did not change in 1H decoupling. Trimethyl phosphate is a good internal standard substance. A 31P-NMR chemical shift of trimethyl phosphate is separate from those of sarin and related compounds. Trimethyl phosphate has one phosphorus atom in the molecule, as does sarin. Since it is advantageous in the conversion of quantitative value, the molecular weight of trimethyl phosphate (m.w. 140.08) is close to that of sarin (m.w. 140.09). By using trimethyl phosphate as an internal standard, it is possible to conduct a quantitative analysis of sarin through 1H decoupled 31P-NMR spectrometry. | eng_Latn | 27,571 |
Study on labeling of antisense oligonucleotides of IgH V1 FR mRNA with ~(125)I | A 18 mer oligonucleotides sequence is synthesized and grafted in 5′ position with a tyramine group. The tyramine derivatized oligonucleotides is labeled with ~(125)I using the chloramines-T method. The stability of ~(125)I-Tyramine-FR-ASON in blood is measured. The labeling yield, radiochemical purity and specific activity are 80.7%, 98.7% and 100 GBq/g, respectively. The radiochemical purity of ~(125)I-Tyramine-FR-ASON is over 90% at 24 h in ambient atmosphere. The polyacrylamide gel electrophoresis results show that there is not any additional band at 2, 6 and 24 h post incubation. The radioiodination method by conjugation of the oligonucleotides with tyramine is very successful. | Author contributions ::: ::: GH helped design the study, establish the animal model, collect and analyze samples, and write the manuscript. YY and DH helped establish the animal model, performed Western blotting, immunohistochemistry analyses. YY and DH also helped analyse data and revise the manuscript. QYW and JK contributed to study planning, analyse and interpret data, review and revise the manuscript. All authors have approved the final version of this article to be published and agreed to be accountable for all aspects of the work in ensuring the questions related to the accuracy or integrity of any part of the work. ::: ::: ::: ::: Disclosure ::: ::: The authors report no conflicts of interest in this work. | eng_Latn | 27,572 |
Zn(II) and Cu(II) complexes of 2-(2-hydroxy-5-methylphenyl)-1H-benzimidazole and crystal structure of 2-(2-hydroxy-5-methylphenyl)-1H-benzimidazolium chloride | 2-(2-Hydroxy-5-methylphenyl)-1H-benzimidazole ligand (HL) and its complexes with Cu(NO3)2, Zn(NO3)2 have been synthesized and characterized. The structures of the compounds were confirmed on the basis of elemental analysis, molar conductivity, magnetic moment, FT-IR, 1H- and 13C NMR. Cu(II) complex has 1: 2 metal: ligand ratio, while Zn(II) complex is 1: 1. Crystal structure of 2-(2-hydroxy-5-methylphenyl)-1H-benzimidazolium chloride (HL · HC1) was determined by single-crystal X-ray diffraction. It crystallizes in the orthorombic, space group P212121and Z = 4. | A method for determination of benzimidazoles residue in raw milk was developed using ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).Ethyl acetate was used to extract the target analyte from raw milk,extraction was degreased and cleaned up with Waters Oasis MCX solid phase extraction(SPE) column for UPLC-MS/MS.The liquid chromatography separation was carried on C18 column(2.1 mm×100 mm i.d.,1.7 μm)with acetonitrile and water(added 0.1% formic acid) as mobile phase at a flow rate of 0.3mL/min.The mass spectrometry was performed in multiple reaction monitoring(MRM)mode.The limits of detection(LOD) of the method were 0.5 μg/kg and the limits of quantification(LOQ) were 1.0 μg/kg.The method has good repeatability and high sensitivity,and can be applied for the determination of ben-zimidazoles in raw milk. | eng_Latn | 27,573 |
The preparation and isomerisation of trans-dicarbonylbis-1,2-bis(diphenylphosphino)ethane]molybdenum(0) | Abstract The reaction of trans -Mo(N 2 ) 2 (Dppe) 2 (Dppe = Ph 2 PCH 2 CH 2 PPh 2 ) with carbon monoxide gives, initially, the previously unknown trans -Mo(CO) 2 (Dppe) 2 , which isomerises in solution to the well-known cis isomer. The reaction was followed by IR spectroscopy under carbon monoxide pressure. | Abstract Exposure of the dorsal skin of hairless mice to the light of a germicidal lamp under standardized conditions produces reproducible, time-dependent increases of putrescine and spermidine concentrations, and a decrease of spermine levels, concomitant with the increase of the rate of DNa synthesis. Systemic or topical treatment of the animals with α-difluoromethylornithine, an enzyme-activated irreversible inhibitor of ornithine decarboxylase, completely prevents the uv light-induced rapid formation of putrescine, and diminishes the enhancement of polyamine turnover rates. A significant effect of the drug on the rate of DNA synthesis could not be shown. The model is suitable for the study of interrelations between polyamine metabolism and cell proliferation and for the screening of compounds designed as inhibitors of polyamine biosynthesis. | eng_Latn | 27,574 |
SIMULTANEOUS SPECTROPHOTOMETRIC ESTIMATION OF ESOMEPRAZOLE AND NAPROXEN IN BULK AND TABLET DOSAGE FORM | Esomeprzole and naproxen are available in tablet dosage form in the ratio 1:25. Two simple, accurate, precise and economic methods; simultaneous equation method and multicomponent method have been described for the simultaneous estimation of esomeprzole and naproxen in tablet dosage form. Absorption maxima of esomeprzole and naproxen in distilled water were found to be 301.0 nm and 262.0 nm respectively. Beer’s law was obeyed in the concentration range 5-50 µg/ml for esomeprzole and 5-50 µg/ml for naproxen. The methods allow rapid analysis of binary pharmaceutical formulation with accuracy. Results of two methods were validated statistically and by recovery studies and were found to be satisfactory. | Purpose ::: This study focuses on nanoscale self–assembly peptides (SAP) modified demineralized bone matrix (DBM) which provided a more effective osteogenesis and regeneration for critically-sized femur defects in goats using the selective cell retention (SCR) strategy. | yue_Hant | 27,575 |
Crystal and Molecular Structure of ω-Amino Acids, ω-Aminosulfonic Acids and Their Derivatives. III. The Crystal and Molecular Structure of γ-Guanidino-β-hydroxypropane Sulfonic Acid | γ-Guanidino-β-hydroxypropane sulfonic acid C4H11O4N3S crystallizes in the monoclinic space group P21/c, with four formula units in a unit cell of dimensions, a=7.44, b=9.89, c=11.11 A and β=97.75°. The crystal structure was determined by the heavy atom method and refined by block-diagonal least-squares to an R-value of 0.12 using intensity data collected photographically. The molecule takes the zwitterionic form, (NH2)2+CNH-CH2CH(OH)CH2SO3−. The skeletal conformation of the molecule is planar trans zigzag. The molecules are held together in the crystal by a three-dimensional network of NH···O and OH···O hydrogen bonds. | Abstract Production anti-scorpion serum fraction requires washing water containing important quantities of (NH4)2SO4. This study presents a combination of the ultrafiltration and the electrodialysis to recover this salt. The application of ceramic ultrafiltration membrane has helped to reduce pollution due to organic matter by completely retained the proteins with an apparent rejection coefficient close to unity. The optimum hydrodynamic parameters such as the average transmembrane pressure and tangential flow rate were determined for ultrafiltration cell. The combination of the UF with the ED allowed concentrating the NH 4 SO 4 salt with a recovery yield of about 74%. | eng_Latn | 27,576 |
Modes of Association of Indometacin with Human Polymorphonuclear Leucocytes | The basic transport properties of indometacin (INDO) were investigated in human blood polymorphonuclear leucocytes (PMNs) of healthy volunteers. The silicone oil cushion centrifugation method was used | e18068Background: One method of therapy deintensification in locally advanced (LA) HPVOPC is to reduce total radiation dose during concomitant chemoradiation (CRT) in a sequential therapy plan. We ... | eng_Latn | 27,577 |
A preparation containing a hemopeptido microperoxidase as active component. | Peroxidase EXTRALELARMENTE PRODUCE BY SOME SPECIES Bacillus pumilus. NEW peroxidase preparation FROM B. pumilus is a preparation of microperoxidase, IE, CONTAINS HEMOPEPTIDO as an active component. PREPARATION HAS IMPROVED HIGH TEMPERATURE STABILITY, high pH and high concentrations of hydrogen peroxide. It may occur WITHOUT UNWANTED catalase activity. | This paper describes a simple and more sensitive reversed-phase HPLC method for the quantification of phenol, 4-nitrophenol and beta-naphthol and some of their glucuronide and sulphate conjugates in aqueous solution and liver perfusate buffer. Methanol-water mobile phases with ion-pairing agents for each phenolic group are detailed. The assay showed good recovery, accuracy and precision and is suitable for the quantification of these phenolic compounds in liver perfusion experiments. | eng_Latn | 27,578 |
Use of gut peptide receptor agonists and antagonists in gastrointestinal diseases. | Because of the numerous actions of gut peptides and the numerous approaches to modification of their activity, it is likely that many other agents will be introduced in the near future. Although a peptide analogue has so far found the largest clinical role, given the problems of peptide pharmacology, the development of nonpeptide gut peptide agonists and antagonists has more promise of clinical usefulness. | We have made significant improvements in the development of a fast, convenient fluorescence imaging technique for evaluating the acid generation efficiency of photoacids in chemically amplified photoresists. A pH sensitive fluorescent molecule, coumarin 6 (C6), is doped into a 193-nm commercial resist system for imaging. For the 193-nm resist systems studied here, the Ka of C6 lies within the range of acid concentrations that can be photogenerated, making it a suitable probe of the acid generation efficiency of various photoacid generators (PAGs). Resist formulations, each containing a candidate PAG, are doped with C6. The resist is spin coated onto wafers and patterned with 5-μm features, with each feature at a different exposure dose. Each wafer is then spectroscopically imaged with an epi-fluorescence microscope. The spectroscopic content of each feature in the dose ramp is determined and the resulting data are analyzed using a two-level optical titration model. The relative quantum yields of acid gene... | eng_Latn | 27,579 |
Environmental Fate of Bisphenol A and Its Biological Metabolites in River Water and Their Xeno-estrogenic Activity | Monitoring of bisphenol A [BPA; 2,2-bis(4-hydroxyphen- yl)propane] and its biological metabolites [4,4‘-dihydroxy-α-methylstilbene (DHMS), 2,2-bis(4-hydroxyphenyl)-1-propanol (BPA-OH), 2,2-bis(4-hydroxyphenyl)propanoic acid (BPA-COOH), and 2-(3,4-dihydroxyphenyl)-2-(4-hydroxyphenyl)propane (3-OH-BPA)] in river waters was performed by solid-phase extraction and GC/MS de termination. The concentrations of BPA, BPA-COOH, BPA-OH, and 3-OH-BPA in the river water ranged from 2 to 230 (8.8 × 10-12 to 1.0 × 10-9 M), from 5 to 75 (1.9 × 10-11 to 2.9 × 10-10 M), from 3 to 16 (1.2 × 10-11 to 6.6 × 10-11 M), and from 3 to 11 (1.2 × 10-11 to 4.5 × 10-11 M) ng L-1, respectively. DHMS, an intermediate in the main degradation pathway of BPA, was not detected in any water sample. Under the aerobic conditions in the river water, BPA disappeared within 8 d of incubation, but BPA-COOH, BPA-OH, and tetraol remained in the supernatant after 14 d of incubation. For the xeno-estrogenic activity of BPA and the metabolites, their ... | A healthy tissue tolerance study1,2 with Beagle dogs was carried out at the Finnish BNCT facility FiR 1 during February-March 1998. Three dose groups of dogs without boron carrier, each comprising five Beagles, and one dose group with BPA-F infusion were irradiated. Individual dose plans1 were done for each dog. The absorbed doses, which were actually delivered to healthy tissues, were monitored in vivo by placing the dosimeters on the shaved skin of the dogs or in the accessible cavities. In this study, absorbed gamma doses were monitored with thermoluminescent (TL) dosimeters, and neutron fluences were determined with activation foils. The obtained results were compared to the calculated values. | eng_Latn | 27,580 |
The X-Ray Structure of Bis((S,S)-2,4-pentanediamine)platinum(II) Ion, [Pt(SS-ptn)2]2+ | The bis((S,S)-2,4-pentanediamine)platinum(II) chloride monohydrate crystallizes in the space group P212121 with four formula units in a unit cell of dimensions a=12.089(3), b=13.547(3), c=10.697(2) A. The crystal structure has been determined from diffractometer data and refined to R=0.052 for 1903 independent reflections. The Pt atom has a square planar coordination by four N atoms, the average value of the Pt-N distance being 2.05 A. The complex has a pseudo two-fold axis which is perpendicular to the coordination plane defined by the four N atoms. The 6-membered chelate ring is of a chair conformation and one methyl group is axial with respect to the chelate ring, while the other is equatorial. From a comparison of the circular dichroism spectra of the diammine-(S,S)-2,4-pentanediamineplatinum(II) and the bis((S,S)-2,4-pentanediamine)platinum(II) ions, the effect of the (S,S)-2,4-pentanediamine on the rotatory strength of the Pt(II) complex has been found to be not additive. | The bacteriocin nisin was extracted in PEG/salt aqueous two-phase systems (ATPS) using the property that the systems can extract hydrophobic proteins. The concentrations of the phase-forming components, PEG 4000 and Na(2)SO(4), were optimized for nisin recovery by means of statistical experimental designs, and it was found that they strongly influenced nisin recovery. The optimal composition of ATPS was found to be 15.99% (w/w) PEG 4000 and 15.85% (w/w) Na(2)SO(4) (pH 2), and the optimal ATPS allowed an 11.60% increase of nisin recovery compared to the standard method of nisin assay. | kor_Hang | 27,581 |
Hydrogen bonding and morphological structure of segmented polyurethanes based on hydroquinone– bis(β-hydroxyethy)ether as a chain extender | Two series of polyether polyurethanes based on hydroquinone bis(β-hydroxyethy) ether (HQEE) or 1,4-butanediol (BDO) as a chain extender were prepared by a one-step bulk polymerization process. Their hydrogen bonding and morphological structure were studied by means of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). Compared with BDO-based polyurethanes, HQEE-based polyurethanes showed better phase segregation and higher extent of ordering in the hard domain. Besides short-range hydrogen bonds, a considerable amount of long-range hydrogen bonds existed in amorphous phase of the hard domain. The soft segment was easier to crystallize, and the melting temperature of the hard domain was elevated in HQEE-based polyurethanes. Its hard domain displayed a banded structure, rather than spherulitic structure in BDO-based polyurethanes. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2895–2902, 1999 | When uredospores of wheat stem rust, Puccinia graminis van tritici (race 15B), were incubated with a 3 mM solution of ammonium chloride-15N, a significant amount of nitrogen 15 was converted into organic nitrogen. Most of this organic nitrogen 15 was found in the ethanol and water extracts, with lesser amounts in the buffer and in extracted spores.Amino acids extracted from the spores all contained excess nitrogen 15. Nitrogen 15 from the inorganic source was diluted by factors of 1.7 and 2.7 in free aspartic and glutamic acids respectively; these amino acids were the most heavily labeled with the isotope. Proline was the most weakly labeled amino acid, the nitrogen 15 being diluted by a factor of 102. Good incorporation of nitrogen 15 into glutamic acid compared to simultaneous poor incorporation into the biochemically related amino acid, proline, parallels previous observations made during carbon 14 experiments with rust uredospores.Fourteen "bound" amino acids were isolated after acid hydrolysis of ext... | eng_Latn | 27,582 |
“Wetting” the Appetite of Spark Ignition Engines for Lean Combustion | Single-cylinder spark ignition engine experiments conducted at constant speed, fixed airflow, and using isooctane as the fuel, demonstrated the effects of fuel-air mixture preparation was changed by varying the time of fuel injection in the induction manifold, near the intake valve port. For comparison, a prevaporized fuel-air mixture was also investigated. Emphasis was placed on determining the effects of mixture preparation on combustion characteristics. Based on the results from this study, the often favored prevaporized mixture of fuel and air may not be the best diet for lean engine operation. /SAE/ | Flow Injection (FI) techniques for use with Atomic Absorption Spectrometry (AAS) ::: have attracted considerable research interest for sample introduction and calibration ::: strategies. The interest continues in on-line preconcentration and matrix modification ::: which are carried out by the incorporation of liquid-liquid extraction, ion-exchange, ::: immobilised reagents, gas/vapour generation and continuous precipitation-filtration ::: devices into suitably designed manifolds. Indirect determination of inorganic anions and ::: organic compounds is becoming routine by FI–flame AAS. The direct analysis of solid ::: samples, which is a shortcoming of flame AAS, was recently carried out by on-line ::: electrolytic dissolutions. [Continues.] | eng_Latn | 27,583 |
CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries | The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti; a=6.295(2) Å; wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space group P63/mmc was confirmed (structure type InPt2Gd; a=4.3022(15) Å, c=7.618(3) Å; wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu-Sn alloys as anode materials for Li-ion batteries. | 1. 4-Cyano-N, N-dimethylaniline (CDA), when administered to rats as a single oral dose (18.5 mg/kg), was rapidly absorbed and eliminated as a mixture of metabolites in the urine (86% dose after 24 h).2. Residues in tissues after 48 h, expressed as μg equiv. of CDA, were: liver, 0.35; kidney, 0.28; testes, 0-08; fat, 006; bone marrow, 0.15 and blood, 0.32.3. Absorption, metabolism and elimination following four consecutive daily doses of CDA (65 mg/kg) were similar to those at the lower dose.4. The major metabolite was 2-amino-5-cyanophenyl sulphate with its mono- and di-N-methyl analogues as minor metabolites. 4-Cyanoaniline, its N-acetyl derivative and an unstable derivative were also found as metabolites.5. Three sulphur-containing metabolites with methylsulphinyl-, methylsulphonyl-, and N-acetylcysteinyl-groups attached to the C2 atom of an N-acetyl group were identified, the latter accounting for 10.3% and 41% of the low and high doses, respectively.6. The sulphur-containing metabolites indicate the i... | eng_Latn | 27,584 |
Use of strontium-90 plesiotherapy for the treatment of a lingual plasmacytoma in a dog | A 12-year-old, 25 kg, intact male St Bernard crossbreed was presented for treatment of a 538 mm ulcerated tumour on the dorsal tongue. Fine-needle aspiration cytology revealed a plasmacytoma. The dog staged negative for evidence of local metastatic or systemic disease. Histopathology confirmed the diagnosis. Treatment with one 150 Gy dose of radiation delivered with strontium-90 plesiotherapy was performed. Side effects were not noted and there was no visible evidence of tumour remaining at 2 months and 1 year after therapy. | Pretreatment of biomass is expected to improve the pulp properties and facilitate the main components in the raw materials to be better used. In this work, the refining energy consumption and properties of the poplar chemithermomechanical pulp (CTMP) from different autohydrolysis pretreatment intensities of wood chips were investigated, and the pulp bleaching ability was also studied. The results showed that the CTMP with autohydrolysis pretreatment at a severity factor of 3.47 could have a 26% energy reduction in pressurized refining, a 60% energy saving in PFI refining, and 44% and 46% increases in tensile and tear indices, respectively. Autohydrolysis pretreatment prior to pulping could result in CTMP with a higher water retention value, higher fines content, better strength properties, lower shives content, and lower bulk and ISO brightness after PFI refining. The brightness of CTMP can be improved by alkaline peroxide bleaching. | eng_Latn | 27,585 |
Catalytic activity and stability toward methanol oxidation of PtRu/CNTs prepared by adsorption in aqueous solution and reduction in ethylene glycol | In this paper, we reported an improved process for the preparation of PtRu/CNTs, which involves the adsorption of Pt and Ru ions on CNTs in aqueous solution and the reduction of the adsorbed Pt and Ru ions on CNTs in ethylene glycol. The surface morphology, structure, and compositions of the prepared catalyst were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy-dispersive spectrometer. TEM observation showed that the particles size of the prepared PtRu alloy was in the range of 2–5 nm, XRD patterns confirmed a face-centered cubic crystal structure. The activity and stability of the prepared catalyst toward methanol oxidation were studied in 0.5 M H2SO4 + 1 M CH3OH solution by cyclic voltammetry, chronoamperometry, and chronopotentiometry. The electrochemical results showed that the prepared catalyst exhibited higher activity and stability toward methanol oxidation than commercial PtRu/C with the same loading amount of Pt and Ru. | The maxillary regions of day-12.5 ICR mouse fetuses were cultured in a chemically-defined serumless medium and the effects of methylxanthine derivatives on cultured palates were studied. Explanted palates were treated for 72 hr in vitro with 0.5-2 mM caffeine (CA), 1-2 mM theophylline (TP), or 1-2 mM theobromine (TB). Although the three compounds tested did not prevent the contact of opposing palatal shelves, palatal fusion was inhibited by CA and TP at a concentration of 2 mM, and the inhibitory effect of CA was more evident than that of TP. On the other hand, TB did not exert an inhibitory effect on palatogenesis at 2 mM. Since the in vitro toxicity of the methylxanthine compounds appeared to correlate well with their in vivo teratogenic potential, the organ culture method of fetal rodent palates should be a useful tool for screening teratogenic agents, especially those causing cleft palate. | eng_Latn | 27,586 |
Acetylcholine receptor antibody as a diagnostic test for myasthenia gravis: results in 153 validated cases and 2967 diagnostic assays. | Anti-acetylcholine receptor (AChR) antibody was undetectable in 26/153 (17%) sera from myasthenia gravis patients assayed by standard RIA using human acetylcholine receptor. Eight of these were found to be positive with a modified protocol using a mixture of normal and denervated AChR, reducing the proportion of "negative" sera to 12%. Many of these were from patients with a short history; two such patients later developed low positive values. Anti-AChR without clinical evidence of myasthenia was found in one of three monozygotic twins of myasthenia gravis patients, and in one of thirty other first degree relatives of a further 17 patients. Anti-AChR is a valuable and highly specific diagnostic test which, with the assay used here, is positive in about 88% of patients with clinical features of myasthenia gravis. | Nondestructive measurements of x-ray and gamma-ray emissions can be used to analyze a sample for plutonium. This report describes the methods and algorithms we have developed for analyzing gamma-ray spectra obtained by using a germanium detector system to accurately determine the relative abundances of various actinide isotopes in a sample. Our methodology requires no calibrations and can be used to measure virtually any size and type of plutonium sample. Measurement times can be as short as a few minutes; measurements are frequently accurate to within 1%. Our methods have been programmed into a computerized analysis code called MGA (Multi-Group Analysis). Our current versions can be run on personal computers (IBM type) and on the DEC VAX microcomputer. Spectral analysis times are usually far less than a minute. 28 refs., 26 figs., 1 tab. | eng_Latn | 27,587 |
Properties of farnesyl pyrophosphate synthetase of pig liver. | Abstract The isolation and partial purification of farnesyl pyrophosphate synthetase of pig liver are described. This enzyme does not have isopentenyl pyrophosphate isomerase, geranyl pyrophosphate synthetase, or geranyl geranyl pyrophosphate synthetase activities. Farnesyl pyrophosphate synthetase catalyzes the formation of farnesyl pyrophosphate through the condensation of geranyl and isopentenyl pyrophosphates. The product of this reaction has been characterized by paper and gas-liquid chromatography. A pH of 7.0 is optimum for the reaction, and Km values for geranyl and isopentenyl pyrophosphates are 4.0 × 10−6 and 2.0 × 10−6M, respectively. An absolute metal requirement has been established for this reaction and Mn++ is approximately 40 times more effective than Mg++ at low ion concentrations. At pH 7.0, 2 × 10−3M iodoacetamide does not inhibit the reaction, but 1 × 10−5M p-hydroxy mercuribenzoate completely inactivates the enzyme. | The pyramid wavefront sensor (PWFS) is a novel wavefront sensor with several inspiring advantages compared with Shack-Hartmann wavefront sensors. The PWFS uses four pupil images to calculate the local tilt of the incoming wavefront. Pupil images are conjugated with a telescope pupil so that each pixel in the pupil image is diffraction-limited by the telescope pupil diameter, thus the sensing error of the PWFS is much lower than that of the Shack-Hartmann sensor and is related to the extraction and alignment accuracy of pupil images. However, precise extraction of these images is difficult to conduct in practice. Aiming at improving the sensing accuracy, we analyzed the physical model of calibration of a PWFS and put forward an extraction algorithm. The process was verified via a closed-loop correction experiment. The results showed that the sensing accuracy of the PWFS increased after applying the calibration and extraction method. | eng_Latn | 27,588 |
[Simultaneous determination of fluoroacetamide and tetramethylendisulfotetramin with gas chromatography-mass spectrography]. | Simultaneous determination of fluoroacetamide and tetramethylendisulfotetramin with gas chromatography-mass spectrography was established. The condition of separation, ways of extraction, the qualitative and quantitative determination of two compounds were discussed. The linear ranges of fluoroacetamide and tetramethylendisulfotetramin were 5-40 micrograms/ml and 0.5-20.0 micrograms/ml, respectively. The recoveries of these two compounds in different sample were 52.25%-94.30% and 61.85%-92.50%, respectively. The method was fast, sensitive and accurate. | A DFT spread Generalized Multi-Carrier (GMC) based Frequency Division Multiple Access (FDMA) scheme, i.e. DFT-S-GMC, is proposed for uplink transmission of wideband mobile communication systems. The scheme achieves spreading gains in the frequency-domain by Discrete Fourier Transform (DFT), and the Frequency Division Multiplexing (FDM) and FDMA by Inverse Filter-Bank Transform (IFBT). By theoretical analysis and simulation results, it is shown that the proposed scheme has good Peak-to-Average Power Ratio (PAPR) performance and is more robust to the Multi-Access Interference (MAI) than the existed main stream uplink schemes, e.g. OFDMA and DFT-S-OFDMA scheme. | eng_Latn | 27,589 |
Quantitative trace analysis with X-ray fluorescence in the scanning electron microscope | The potential of a scanning electron microscope will be enhanced markedly by adapting the X-ray fluorescence for material analysis. The illuminating system “rontgenbox” enables the analyst to execute analyses in the concentration range from 100 percent down to the low ppm range without time consuming preparation steps. X-ray intensities of traces are measured for different anodes in the elemental range fromZ=11 to 90 (sodium to thorium). | A study was carried out on the separation of active anthraquinone ingredient in Chinese rhubarb using High-Speed Countercurrent Chromatography with acid-base accommodationt. Trifluoroacetic acid (TFA) was used as the retaining acid and ammonia liquor as the eluent base. The solvent system was n-hexane-acetic ester-methanol-water (ratio by volume was 9 ∶1 ∶5 ∶5). The separative product was confirmed as five pure anthraquinone of Chinese rhubarb by High Performance Liquid Chromatography (HPLC). | eng_Latn | 27,590 |
Chiral HPLC Determination of Ketoprofen | Objective:To establish an HPLC method for the separation and determination of ketoprofen.Methods: Operating conditions were as follows:Sumichiral OA-2500 column,0.03 mol·L~(-1) neodymium acetate-methanol mobile phase with a flow rate of 0.8 mL·min~(-1),and UV detection at 254 nm.Results:Active constituents ketopro- fen can be separated effectively.The RSD was 1.4% (n=6).Conclusion:The method is accurate,rapid,simple, and provides a scientific basis for industrial production and quality control of ketoprofen. | SummaryThe metabolism of betahistine, demethylbetahistine and 2-(2-hydroxy-ethyl) pyridine in the rabbit leads to the urinary excretion of acidic metabolities, including 2-pyridylacetate, which is excreted in part as N-2-pyridylacetylglycine. Other unidentified Koenig-positive compounds were in the acidic fraction. | eng_Latn | 27,591 |
[Reabsorption of standardised intramuscular haematomas in rabbits treated with streptokinase per os (author's transl)]. | Standardised i.m. haematomas in rabbits were studied with and without oral administration of Varidase (containing streptokinase and streptodornase). 125I-fibrinogen was mixed with 2 ml of rabbit blood and reinjected i.m. The standardised haematomas were reabsorbed after 12 to 14 days. During the 3-day administration period of streptokinase the counts measured over the haematoma were even higher than in control animals. As during the therapy a high fibrinolytic activity was found, additional spontaneous bleeding into the haematomas may be suspected. When oral administration of streptokinase was stopped the decrease of counts detected in those animals was significantly accelerated as compared to non-treated animals. This indicates an accelerated reabsorption of those haematomas treated with streptokinase in a low concentration. These results were confirmed by microscopic findings. | Soluble starch as raw materials and Span60 and Tween 60 as complex emulsifier, N,N'-methylene-acrylamide (MBAA) crosslinker, in the inverse suspension system to trigger K2S2O8 -NaHSO3 Synthesis ofneutral starch microspheres, and then ether agent GTA starch microspheres and neutral response system in the cationic starch microspheres. And use of infrared spectroscopy, scanning electron microscopy, particle size analyzer on the cationic starch microspheres were characterized analysis. The results showed that: starch- cation of the ball the whole round shape, surface roughness, the average size of 20.2 μm. Infrared tests showed that: starch and MBAA in cross -linking reaction, and grafted a quaternary ammonium salt cation group. To methylene blue for small organic molecules model to study the microspheres on methylene blue adsorption characteristics, cation starch microspheres methylene blue on the adsorption of the equation and Langmiur Freundlich equation. | eng_Latn | 27,592 |
[Effect of acute alcoholic intoxication on the antigenic composition of soluble proteins in the rat brain]. | Cross immunoelectrophoresis was used to study antigenic composition of the brain of rats preferring water, or 15% ethanol and of intermediate group animals. The rat brain showed 6 antigens, one of them was found to be neurospecific. The intermediate group animals and those preferring ethanol differed from those preferring water in that they demonstrated two antigens which were found to be neuro-nonspecific. The content of the neurospecific protein S-100 in the cerebellum measured by rocket immunoelectrophoresis was demonstrated to be the same in animals preferring water and ethanol. A single intraperitoneal injection of 25% ethanol (2.5 g/kg) to the intermediate group rats brought about a change in the composition of neuro-nonspecific soluble antigens of the brain. | Abstract A synthesis and stereochemistry confirmation of a constituent recently isolated from the whole plant Isodon excisus is reported. An enantioselective catalytic boron-mediated reduction of an α-bromoketone was utilized in the key synthetic transformation. The methodology described herein was also used for the synthesis of the natural product's enantiomer and several derivatives. In addition, the compounds were evaluated for inhibitory activity in a caspase induction assay. The natural product was found to be devoid of activity, but several derivatives had moderate inhibitory activity (EC 50 | eng_Latn | 27,593 |
Determination of eucalyptol and borneol in Heidou Liuyou Ointment by GC | Objective To establish a GC method for the determination of eucalyptol and borneol in Heidou Liuyou Ointment.Methods The column was Rtx-WAX(30 m×0.25 mm×0.25 μm),and the gas flow rate was 1.5 mL·min-1.Cyclohexanone was selected as internal standard.The temperature program of column oven was set as follows:60 ℃ for 7 min,increased to 140 ℃ at a rate of 15℃·min-1 and held for 5 min.The detector was FID.Results Under this condition,eucalyptol showed good linear relationship in the range between 0.320 6 and 8.015 8 μg(r=0.999 9)and borneol showed good linear relationship in the range between 0.165 2 and 4.130 7 μg(r=0.999 9).The average recoveries of eucalyptol and borneol(n=6)were 98.7% and 98.9% with RSD 1.5% and 1.6%,respectively.Conclusion The method is simple,rapid and can determine the content of eucalyptol and borneol accurately with higher sensitivity,which can be used as the determination control method for Heidou Liuyou Ointment. | This invention is a composition of matter and method of preparing the same. More specifically the present invention is a medicated vapor candle consisting of a homogenous mixture having approximately three parts petroleum jelly containing the active ingredients of camphor, menthol and eucalyptus, melted and mixed with four parts candle wax. The active ingredients, by volume, of approximately 5% camphor, 2.5% menthol and 1.2% eucalyptus oil. | eng_Latn | 27,594 |
Methane formation from methyl‐coenzyme M in a system containing methyl‐coenzyme M reductase, component B and reduced cobalamin | Purified methyl-CoM reductase of Methanobacterium thermoautotrophicum was found to catalyze the reduction of methyl-coenzyme M to methane at a specific rate of 100 nmol × min−1× mg protein−1 in a system containing partially purified component B, cob(III)alamin (B-12a), and, as electron donors, dithiothreitol or SnCl2. Under these experimental conditions B-12a was reduced to cob(II)alamin (B-12r), which is known to disproportionate to cob(I)alamin (B-12s) and B-12a to a slight extent. Methane formation from methyl-CoM was inhibited by propyl iodide, methyl iodide, chloroform and carbon tetrachloride, which were shown to react with B-12s to the corresponding light-sensitive alkyl cobalamin. Inhibition by propyl iodide was less effective in light-exposed samples. From these findings it is concluded that in this assay system B-12s might serve as electron donor for the enzymatic reduction of methyl-CoM to methane. | Carbamazepine, which is an anti-epileptic drug, is ubiquitously present in municipal wastewater. Owing to its recalcitrant chemical structure, carbamazepine is not significantly removed during conventional biological treatment or even by membrane bioreactor (MBR). With the ultimate aim of providing insights into the strategies to enhance carbamazepine removal, the effect of key operational parameters, namely, loading rate (2–750 μg/L• d), pH (5–9), mixed liquor suspended solids (MLSS) concentration (1–15 g/L) and dissolved oxygen (DO) (<0.5–5 mg/L) on the removal of carabamazepine by MBR was systematically studied. Results obtained in this study revealed negligible influence of pH and of MLSS concentration (beyond 5 g/L) on the removal of carbamazepine. The removal rate, however, was significantly enhanced under a DO concentration of less than 0.5 mg/L, suggesting that an alternating anoxic-oxic environment in MBR would achieve high removal. Significantly enhanced (287 mg/g vs. 0.02 mg/g) adsorption of ca... | eng_Latn | 27,595 |
Shockwave Therapy for Patients with Plantar Fasciitis: A One-Year Follow-up Study | The effect of shockwave therapy was investigated in 79 patients (85 heels) with plantar fasciitis with one-year follow-up. There were 59 women and 20 men with an average age of 47 (range, 15-75) years. Each patient was treated with 1000 impulses of shockwave at 14 kV to the affected heel. A 100-point scoring system was used for evaluation including 70 points for pain and 30 points for function. The intensity of pain was based on a visual analogue scale from 0 to 10. The overall results were 75.3% complaint-free, 18.8% significantly better, 5.9% slightly better and none unchanged or worse. The effect of shockwave therapy seemed cumulative and was time-dependent. The recurrence rate was 5%. There were no device-related problems, systemic or local complications. Shockwave therapy is a safe and effective modality in the treatment of patients with plantar fasciitis. | An efficient algorithm is presented for the numerical solution of the Poisson–Boltzmann equation by the finite difference method of successive over-relaxation. Improvements include the rapid estimation of the optimum relaxation parameter, reduction in number of operations per iteration, and vector-oriented array mapping. The algorithm has been incorporated into the electrostatic program DelPhi, reducing the required computing time by between one and two orders of magnitude. As a result the estimation of electrostatic effects such as solvent screening, ion distributions, and solvation energies of small solutes and biological macromolecules in solution, can be performed rapidly, and with minimal computing facilities. | eng_Latn | 27,596 |
Evaluation of some substrates and potential inhibitors of tissue pyroglutamyl aminopeptidase I | A fluorometric enzyme assay was developed to evaluate the ability of a variety of compounds to bind to and/or inhibit pyroglutamyl aminopeptidase I. Among these compounds were a series of chloromethyl ketone analogues of thyrotropin releasing hormone (TRH) which had previously been shown to possess TRH-like activity in the central nervous system and have now been found to be good inhibitors of pyroglutamyl aminopeptidase. Thus, it is suggested that the observed TRH-like CNS activity could derive indirectly from inhibition of endogenous TRH degradation by pyroglutamyl aminopeptidase I. | The present invention relates to vectors useful for the administration of active principles (PA), preferably medicinal or nutritional, especially orally or parenterally. The technical problem solved by the invention is that consisting in the supply of vectors formed by (nano) or (micro) particles based on polyamino acids, and which are inert with respect to PA (proteins), of controllable granulometry, resistant and economical. The invention has an average particle size of less than 200 mum and consists of a polyamino acid of the Leu / Glu type, in which Leu / Glu + Leu> = 20% and Mw> = 10,000 D. | eng_Latn | 27,597 |
Judd-Ofelt analysis and radiative properties of LiLa(1 x)Eux(PO3)4 | Abstract Judd–Ofelt (J–O) theory has been applied to a series of LiLa1−xEux(PO3)4 (x = 5%; 10%; 15%; 20% and 30%) polycrystalline powders based on their emission spectra. J–O intensity parameters Ωλ (λ = 2, 4) and various radiative properties such as the radiative transition probability (A), radiative life time (τR), branching ratio (βR) and stimulated emission cross-section (σe) have been determined. The observed trend for J–O parameters (Ω2 | The present invention is directed to phosphatidylinositol or lysophosphatidylinositol concentration indicators relates to efficacy evaluation method of a medicament having a therapeutic or prophylactic effect for a disease EL activity is associated. Further, the present invention relates to a kit for use in screening methods and method of the EL active inhibitors using phosphatidylinositol. | eng_Latn | 27,598 |
Bioavailability of potassium from controlled-release tablets with and without water loading | The relative availability of potassium from a controlled-release multiple-units tablet (Kalinorm) and a single-unit tablet (Slow-K) were compared in 13 volunteers on a low potassium diet (less than 30 mmol), by observing changes in urinary potassium excretion after administration of a single dose of 32 mmol potassium, either with or without water loading. Irrespective of procedure, the two products had the same extent of availability. The use of water loading, and special precautions about the level of dietary potassium and its composition when studying urinary potassium excretion, are discussed. It is suggested that water loading should be avoided when investigating the rate of potassium excretion. | Abstract Cation concentration profiles in solid—solution scales on NiCo alloys have been calculated by making use of Wagner's theoretical analysis. As a result of the computation method used, it becomes unnecessary to incorporate experimental values in the calculation for either the parabolic rate constant, k p , or the boundary conditions of the cation profile. The agreement between the independently determined theoretical and experimental cation profiles provides strong support for Wagner's model. The calculated variation of k p with alloy composition is also in agreement with the experimental data. | eng_Latn | 27,599 |
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