The Abbott enzyme immunoassay (Abbott Laboratories, North Chicago, Ill.) for human T-cell lymphotropic virus type III (HTLV-III) antibody was evaluated to determine the effect of using heat-inactivated (56 degrees C for 30 min) serum as the sample. Each of 58 nonreactive serum samples gave a higher A492 value when tested after heat inactivation. Ten of the samples became reactive after heating....

A "sarcosine oxidase" was prepared from a creatinine-decomposing strain of Pseudomonas aeruginosa. The enzyme is inactivated by drying, lyophilization, and dialysis against distilled water. No dialyzable cofactor was found. Optimal activity of the enzyme is reached at pH 7.8. Enzyme activity is directly proportional to enzyme concentration and also to substrate concentration up to the point of ...

Streptococcal DNAse C is more resistant to heat inactivation than the A or B enzyme. DNAses A and C are indifferent to the bacterial ribonucleic acid inhibitor whereas the B enzyme is markedly inhibited. Prolonged digestion with relatively large amounts of DNAse B results in chemical and biological destruction of the inhibitor. Ribonuclease as well as deoxyribonuclease activity is associated wi...

An assay for measuring hexosaminidase A in serum and leucocytes is described in which a centrifugal analyser is used for automation of the enzyme assays after manual heat inactivation. The assay was used in a screening programme to identify heterozygotes for Tay-Sachs disease in Ashkenazi Jewish subjects in the UK. The first results from this programme indicate a carrier frequency of 1 in 27. A...

Munoz, J. (Rocky Mountain Laboratory, Hamilton, Mont.), and B. M. Hestekin. Antigens of Bordetella pertussis. IV. Effect of heat, Merthiolate, and formaldehyde on histamine-sensitizing factor and protective activity of soluble extracts from Bordetella pertussis. J. Bacteriol. 91:2175-2179. 1966.-Both histamine-sensitizing and protective activities of soluble preparations from Bordetella pertuss...

The response of a representative virus and indicator bacteria to heating, solar irradiation, or their combination, was investigated in a controlled solar simulator and under real sun conditions. Heating showed higher inactivation of Escherichia coli compared to the bacteriophage MS2. Heating combined with natural or simulated solar irradiation demonstrated a synergistic effect on the inactivati...

1. Rat liver and heart major isoenzymes of NADP-isocitrate dehydrogenase have each been purified about 100-fold by a combination of ammonium sulphate fractionation and chromatography on ion-exchange cellulose and their properties compared. 2. The properties were similar in respect of pH, inhibition by Hg(2+) and Michaelis constants for isocitrate and NADP. 3. Some of the properties of the isoen...

  SUMMARY Since at oocyte retrieval for in vitro fertilization there is some FF become incorporate to egg, we decided to investigate the effect of this fluid on preimplantation embryo development in vitro. FF was obtained at the time of oocyte retrieval for IVF, centrifuged and then either inactivated by heat and stored at 4°c or without inactivation stored at-20°c until used. Late 2-cell emb...

The method by which sodium nitrite may act to prevent germination or outgrowth, or both, of heat-injured spores in canned cured meats was investigated by using Clostridium perfringens spores. Four possible mechanisms were tested: (i) prevention of germination of the heat-injured spores, (ii) prior combination with a component in a complex medium to prevent germination of heat-injured spores, (i...

Aqueous suspensions of Bacillus subtilis NCTC 8236 spores, surviving gamma irradiation from a cesium-137 source, exhibited an enhanced rate of inactivation compared to nonirradiated spores when heated with 0.04% phenylmercuric nitrate. The enhanced rate of inactivation, observable from survival curves, was noted when spores were irradiated with 150,000 rad under air in either the presence or ab...