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S F Gottlieb

Publications and source records attributed to S F Gottlieb.

35 records · Page 2Linked to original sources
PubMed1977

Effect of increased pressures of oxygen, nitrogen, and helium on activity of a Na-K-Mg ATPase of beef brain.

Increased pressure of O2, N2,or He exert inhibitory or stimulatory effects on activity of Na-K-Mg ATPase obtained from beef brain cortex. Oxygen at 2 ATA and N2 at 4 ATA exert significant inhibitory effects whereas 3 & 4 ATA O2, 1-3 ATA N2 exert significant stimulatory effects. Effects of He on ATPase activity are qualitatively similar to those of N2. The effects of the gases are not qualitatively altered by the presence or absence of ATP. A pressure compensated analysis reveals that at the same pressures, O2 and N2 exert different effects of ATPase activity.

Adenosine Triphosphatases↗
PubMed1976

Ageing and ovarian delta 5-3 beta-hydrosteroid dehydrogenase in the pregnant mouse.

Aged (12- to 14-month-old) C57BL oestrous mice exhibited significantly lower (P less than 0-001) ovarian delta 5-3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) concentration, specific activity and total content than young (3-month-old) oestrous mice, suggesting a decrease in the potential of the older animals to produce ovarian delta 4-3-oxosteroids. Mice in both age groups maintaining pregnancy to 10 or 18 days post coitum (p.c.) had similar values for activity of ovarian 3 beta-HSD. In the aged females in which foetal resorption had occurred, the majority of foetuses had been resorbed by 10 days p.c. However, ovarian 3 beta-HSD activity in these animals was not significantly different from that of young or aged mice maintaining pregnancy. By day 18, however, ovarian dehydrogenase activity in aged females failing to maintain pregnancy had decreased significantly. It is suggested that foetal death in aged mice is not the result of a deficiency in ovarian 3 beta-HSD, but rather may initiate luteal regression and consequently a decline in 3 beta-HSD.

Aging↗
PubMed1976

Effects of increased pressures of oxygen and air on short-term memory in mice.

The purpose of this study was to determine the effects of increased oxygen tensions on short-term memory in mice following one-trial, passive-avoidance learning. Neither increased oxygen tensions per se nor 6 ATA air had any measurable deleterious effects on retention of the learned task. Interference with memory of the learned task occurred only when the animals were subjected to oxygen-induced convulsions. Oxygen-induced convulsions did not result in permanent brain damage such that the animals were incapable of learning. Oxygen-induced convulsions following a 2-h interval after learning did not result in a retrograde amnesia. It appears that oxygen-induced convulsions interferes with the consolidation process of memory.

Air Pressure↗
PubMed1975

Effects of increased partial pressures of oxygen on the embryonic and post-embryonic development of drosophila melanogaster.

The objective of this investigation was to study the effects of increased oxygen pressures on the development of Drosophila melanogaster. Oxygen is a potent inhibitor of embryonic and post-embryonic development of Drosophila. The lowest partial pressure of O2 (Po2) found to elicit measurable inhibitory effects on development is 0.6 ATA. Continuous exposure of developing Drosophila to 0.6 ATA O2 elicits primarily a larvicidal effect; surviving larvae exhibit delays in initial puparium formation and in mean day of adult eclosion: several resultant adults exhibit the effects of O2-induced teratogenesis in that body and wing abnormalities become manifest which do not breed true on matings and back crosses. Continuous exposure to 0.8 or 1.0 ATA O2 results in developmental arrest in the second larval instar followed by death. This development arrest is reversible depending upon the duration of exposure. As concerns lethality, early larval stages are more sensitive to O2 than late larval stages which, in turn, are more sensitive than early or late pupal stages: the embryo is the more resistant of the development stages. As concerns sensitivity for teratogenesis, the embryo is the most sensitive stage.

Animals↗
PubMed1968

Effect of high oxygen tensions on the growth of selected, aerobic, gram-negative, athogenic bacteria.

The in vitro effects of high O(2) tensions (P(O2)) on aerobic, enteric pathogens were examined at pressures of up to 3 atm absolute. Organisms from the genera Salmonella, Shigella, and Vibrio were usually subjected to 24-hr exposures. Tensions of 0.87, 1.87, and 2.87 atm absolute of O(2) (plus traces of CO(2) and N(2)) became progressively inhibitory for Salmonella and Shigella growth, but were bactericidal only for V. comma strains at tensions greater than 0.87 atm absolute of O(2). Growth inhibition of enteric organisms resulted from increased P(O2), rather than pressure per se, and could be mitigated nutritionally; an appropriate carbohydrate source is at least partially involved. Further studies with vibrios indicated that such mitigation was independent of medium pH. In addition, a synergistic relationship existed between O(2) and sulfisoxazole when tensions from 0.87 to 2.87 atm absolute of O(2) were maintained for 3 to 24 hr. Synergism occurred even under nutritional conditions which negated growth inhibition by O(2) alone. Bactericidal concentrations of sulfisoxazole, in the presence of increased P(O2), were reducible up to 4,000-fold. The combined procedure employed in this investigation, by use of an antimicrobial drug of known action, which also synergizes with O(2), plus nutritional studies, suggests a means for establishing a site of O(2) toxicity. These data support the concept that O(2) inhibition of growth represents a metabolic disturbance and that metabolic pathways involving p-aminobenzoic acid may be O(2)-labile. Such an approach could also guide development of antimicrobial agents as O(2) substitutes for promoting synergism.

Carbohydrate Metabolism↗
PubMed1966

Bacterial nutritional approach to mechanisms of oxygen toxicity.

Gottlieb, Sheldon F. (Union Carbide Corp., Tonawanda, N.Y.). Bacterial nutritional approach to mechanisms of oxygen toxicity. J. Bacteriol. 92:1021-1027. 1966.-Inhibition by oxygen of growth of the bacterium Achromobacter P6 was reversed by amino acid supplements. The reversal of oxygen-induced growth inhibition was not due to the presence of reducing substances in the growth medium. Oxygen primarily exerts a bacteriostatic effect. The oxygen inhibition of growth occurred over a wide pH range. Oxygen inhibition of growth was observed when 1-amino-2-propanol, acetate, lactate, citrate, or glucose was used as the sole source of carbon and energy. No inhibition of growth was obtained when succinate, fumarate, malate, or glutamate was used as the source of carbon and energy. Oxygen markedly depressed the respiration of P6 when 1-amino-2-propanol was the substrate. There was no depression of respiration under oxygen with succinate as substrate. P6 grown in the presence of high oxygen tensions had a higher rate of respiration under oxygen than similar air-grown cells. Chloramphenicol did not affect the rate of oxygen consumption or cause a further depression of the respiratory rate in the presence of oxygen. It is suggested that microbes may serve as a model system for studying the cellular and subcellular mechanisms of oxygen toxicity.

1-Propanol↗
PubMedDate not supplied

Reduction of rattlesnake-venom-induced myonecrosis in mice by hyperbaric oxygen therapy.

Hyperbaric oxygen therapy (HBOT) at 1, 2, and 2.75 atmospheres absolute (ATA) was used to treat rattlesnake (Crotalus atrox) venom-induced tissue damage and edema in thigh muscles of mice. Tissue damage was evaluated by double-blind histopathologic examination: tissue edema was determined by measuring tissue water content. A total of 10 intermittent exposures to oxygen over a period of 4 days at 2 and 2.75 ATA did not influence the resolution of venom-induced tissue edema, whereas tissue damage was significantly ameliorated as compared to air-treated envenomated controls. HBOT also promoted healing in the venom-injected mice as evidenced by the presence of regenerating muscle cells. It is concluded that HBOT may limit rattlesnake venom-induced myonecrosis and promote healing in a dose-response relationship without reducing venom-induced edema.

Animals↗