Search PubMed⌕ Search

Biomedical subjects

S Marcus

Publications and source records attributed to S Marcus.

At least 163 records · Page 9Linked to original sources
PubMed1966

Detoxified bacterial endotoxns. II. Preparation and biological properties of chemically modified crude endotoxins from Salmonella typhimurium.

Martin, William J. (University of Utah, Salt Lake City), and Stanley Marcus. Detoxified bacterial endotoxins. II. Preparation and biological properties of chemically modified crude endotoxins from Salmonella typhimurium. J. Bacteriol. 91:1750-1758. 1966.-Chemical modification of a crude endotoxin prepared by the Roschka-Edwards (RE) procedure from a strain of Salmonella typhimurium yielded products which were nontoxic for mice and had reduced fever effects in rabbits. A reduction in rabbit pyrogenicity of approximately 100 times was noted with a potassium periodate-treated RE preparation when compared with the parent RE preparation. Measured in a similar fashion, pyrogenicity of a potassium methylate-treated RE preparation was reduced by a factor of 10 while pyrogenicity of a boron trifluoride RE preparation was unchanged. All of these endotoxoids, including the parent RE preparation, showed little toxicity for mice. Immunogenicity was determined in mice by comparing Boivin, RE, and endotoxoid preparations with a heat-killed, phenol-preserved (HP) vaccine prepared from the same strain of S. typhimurium. Employing a 10 ld(50) challenge, the protective immunogenicity of the respective vaccines was determined by active immunized mouse protection tests. Although two 100 mug immunizing doses of the Boivin, RE, and the respective endotoxoid preparations varied in mouse protection (potassium methylate RE > Boivin > RE > boron trifluoride RE > potassium periodate RE), it was evident that, with the exception of the potassium methylate preparation, the HP vaccine yielded greatest protection against the 10 ld(50) challenge with S. typhimurium. Further mouse protection experiments suggested that the minimal immunogenic dose of the potassium methylate RE vaccine preparation was approximately 50 mug. These data indicated an approximate fivefold difference between the minimal pyrogenic dose (10 mug) and the minimal immunogenic dose (50 mug). These findings further suggest that potassium methylate RE vaccine preparations should be considered in the search for less toxic enteric fever vaccines.

Animals↗
PubMed1964

Relation of pyrogenic and emetic properties of enterobacteriaceal endotoxin and of staphylococcal enterotoxin.

Martin, William J. (College of Medicine, University of Utah, Salt Lake City), and Stanley Marcus. Relation of pyrogenic and emetic properties of enterobacteriaceal endotoxin and of staphylococcal enterotoxin. J. Bacteriol. 87:1019-1026. 1964.-The pyrogenic, endotoxic fraction of enterobacteriaceal organisms, isolated in a relatively impure or purified state, is both pyrogenic in rabbits and cats as well as emeticogenic in cats in microgram amounts. Employing classical methods for preparation of enterobacteriaceal endotoxin from known enterotoxic strains of Staphylococcus aureus yielded preparations with less than one-hundredth the activity of the enterobacteriaceal material. However, a purified enterotoxin material from an S. aureus strain, with protein-like rather than polysaccharidelike properties, was found to be both pyrogenic and emeticogenic in microgram amounts. These results suggest the probability that the enterobacteriaceal pyrogenemetic substance(s) is a significant part of the whole cell, whereas the staphylococcal enterotoxin is elaborated as a metabolic product which apparently does not accumulate in the whole cell.

Animals↗
PubMedDate not supplied

Serum growth hormone and free fatty acid levels in heifers and cows before, during and after parturition.

A large number of blood samples was taken from the jugular vein of 18 cows or heifers during parturition, especially during stage II. In 9 animals an increase in serum growth hormone was observed and the peak occurred within the period which began when the forelegs of the calf became visible in the vulva, and ended a few minutes after expulsion of the calf. In typical cases, the growth hormone peak was preceded by a progressive increase, and followed by a gradual decrease in the hormone level. The total duration of the phenomenon amounted to a few hours. During the days before and after parturition, no change in growth hormone concentration could be noted. The serum free fatty acid values were high during parturition.

Animals↗