An infectivity assay for MS2 ribonucleic acid (RNA), which uses bacterial spheroplasts of an F(-) strain of Escherichia coli, has an efficiency of 10(-5) infected spheroplasts per RNA molecule. The characteristics of this assay and the influence of several parameters are presented. Important variables include the duration of exposure of the cells to lysozyme-ethylenediaminetetraacetic acid, the...

OBJECTIVE The purpose of this study was to develop a simpler method to measure severely reduced glomerular filtration rate (GFR) for patients with a GFR below 30 mL/min. METHOD The GFR was measured in 24 patients using both the 51Cr EDTA slope-intercept method (the conventional method) and 99mTc-DTPA with our proposed simpler GFRn method. RESULTS The correlation coefficient was 0.92 between...

Zinc isotope separations were studied by displacement chromatography using the chelating properties of malate, citrate and lactate exchange resin and EDTA as ligands. After each chromatographic operation, the heavier zinc isotopes were found to preferentially fractionated into the carboxylate complex solution phase. The separation coefficients (epsilon) for zinc isotope separation had the large...

The current phenotypic methods for detecting carbapenemase-producing Enterobacteriaceae (CPE) allow differentiation between class A and B carbapenemases, but they cannot confirm in a single test class D OXA-48 carbapenemase producers. In this study, we evaluated a new phenotypic test, the OXA-48 disk test, which is based on an imipenem disk and two blank disks adjacent to the imipenem disk, loa...

The stability of four hemoglobins (Hb) in dimer forms (low concentration) were investigated by the kinetics of denaturation. The rate constants of denaturation were obtained by variation of 280 nm absorption versus time in 10 mM Tris-HCl, 10 mM EDTA, pH 8.0 at 45 degrees C in the absence and presence of 0.5 M ethanol, dimethyl sulfoxide (DMSO), formamide, and glycerol. The results show the tren...

Competitive immunoassays for Cd(II), Co(II), Pb(II) and U(VI) were developed using identical reagents in two different assay formats, a competitive microwell format and an immunosensor format with the KinExA 3000. Four different monoclonal antibodies specific for complexes of EDTA-Cd(II), DTPA-Co(II), 2,9-dicarboxyl-1,10-phenanthroline-U(VI), or cyclohexyl-DTPA-Pb(II) were incubated with the ap...

Gastrula and neurula embryos of Cynops pyrrhogaster were dissociated into cell suspensions with ethylenediaminetetraacetic acid (EDTA), trypsin, and solution. The cells were cultured in Niu-Twitty's balanced salt solution and their aggregates were examined histologically. The results indicated that the capacity of amphibian embryonic cells for aggregate formation, sorting out, and notochord dif...

The specificity of macrophage elastase obtained from mouse peritoneal exudative macrophages was determined in the hydrolysis of the oxidized insulin B-chain. This elastase hydrolysed two bonds, namely Ala-Leu and Tyr-Leu. The rate of hydrolysis of the latter was two to three times greater than that of the former. The hexapeptide Glu-Ala-Leu-Tyr-Leu-Val, obtained by cleavage of the insulin B-cha...

A collagenolytic enzyme was extracted from the 6000 g sediment of homogenized postmortal human colon tissue. The enzyme digests native collagen at neutral pH. The enzyme has been concentrated by ammonium sulfate precipitation. The collagenolytic activity was measured using [1-14C]acetylated calf skin collagen, solubilized in 0.1 g/1 acetic acid. There was a significant inactivation of the enzym...

Disodium phosphonoacetate when administered orally or topically to mice experimentally infected with herpes simplex virus was able to significantly reduce the mortality associated with the agent. In addition, this compound was able to reduce herpesvirus lesions on the corneas of infected rabbits.