The Ames procedure with Salmonella typhimurium strain TA100 was used to follow the detoxication by rat liver fractions of two series of aliphatic epoxides. The epoxides employed were 3-chloro-, 3,3-dichloro- and 3,3,3-trichloropropylene oxides and also p-methoxyphenyl-, phenyl- and p-nitrophenylglycidyl ethers. In our procedure with preincubation of the epoxides with rat liver fractions prior t...

Rapid isolation of high-purity microbial genomic DNA is necessary for genome analysis. In this study, the authors compared a one-hour procedure using a microwave with enzymatic and boiling methods of genomic DNA extraction from Gram-negative and Gram-positive bacteria. High DNA concentration and purity were observed for both MRSA and ESBL strains (80.1 and 91.1 μg/ml; OD260/280, 1.82 and 1.70, ...

A new enzymatic method for rapid direct measurement of serum tyrosine is described, based on the amperometric measurement of the rate of oxygen consumption when tyrosine is oxidized in the presence of the enzyme tyrosinase in a phosphate buffer (0.1 mol/liter, pH 7.4). A Beckman Glucose Analyzer with a Clark electrode is used for the measurement. The procedure does not require removal of serum ...

A procedure for the measurement of pregnanetriol in urine by gas chromatography is described. The internal standard is added to the standards, controls and unknowns prior to the enzymatic hydrolysis of the steroid conjugates. Next, the hydrolyzed steroids are extracted from urine and converted to the volatile trimethylsilyl ether derivatives prior to gas chromatography. The initial addition of ...

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Rapid amplification of cDNA 5' ends (5'-RACE) is routinely used for the sequence analysis of the upstream noncoding regions of cellular mRNAs; however, it represents a tedious and cost-intensive procedure. By employing 5' phosphorylated gene-specific primers for first-strand cDNA synthesis, we cut short the previously established reverse ligation and amplification protocol of Mandl and coworker...

We describe here a simple, time-saving method for separating alkaline phosphatases on cellulose acetate, with a parallel detection of serum protein pattern. The staining procedure is based on a coupling reaction between the reaction product of alpha-naphthol with Fast Red Violet LB. The enzymatic reaction is done by bringing the cellulose acetate strip containing the phosphatase band into conta...

The formalism of Hybrid Functional Petri Nets (HFPN) has proved its convenience for simulating biological systems. The drawback of the noticeable expressiveness of HFPN is the difficulty to perform formal verifications of dynamical properties. In this article, we propose a model-checking procedure for Timed Hybrid Petri Nets (THPN), a sub-class of HFPN. This procedure is based on the translatio...

Extracts of stationary-phase mycelia of the spectinomycin producer Streptomyces flavopersicus ATCC 19756 catalyzed inositol dehydrogenase, L-glutamine:inosose aminotransferase, 2-epi-streptamine:inosose aminotransferase, streptamine:inosose aminotransferase, N3-methyl-2-deoxystreptamine:inosose aminotransferase, and aminodeoxy-scyllo-inositol:inosose aminotransferase reactions, as detected with...