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Endogenous concentrations of putrescine, spermidine, spermine and related biosynthetic enzymes were not affected by the administration of bacterial endotoxin and the subsequent development of fever in rabbits. In addition, the febrile response to endotoxin was unaffected either by the ornithine
Intraperitoneal injection of putrescine induced dose-related hypothermia in rats. The effect was more pronounced at room temperature (22 degrees C) than in a warm environment (30 degrees C), the maximum hypothermia (-2.64 +/- 0.29 degrees C, 30 min. after treatment) being obtained with the dose of
The effect of polyamine depletion on the survival response of human lung carcinoma cells (A-549) to acute heating at 45 degrees C and its effect on the induction and decay of thermotolerance were investigated in exponential and plateau-phase cells. A 48-h exposure to 1 mM
Although hyperthermia produces teratogenic effects in a great variety of animal species, the molecular mechanisms by which hyperthermia exerts its action remain unknown. We have studied the implications of polyamines in contragestational hyperthermia in rats. Our results show that the
The issue of how polyamines act to sensitize cultured cells to the lethal effects of hyperthermia was investigated using Chinese hamster cells which were induced to express thermotolerance. Intracellular levels of these naturally occurring polycations were manipulated in certain situations by
Temporal studies were made of factors associated with increased RNA synthesis in guinea pig liver during Q fever. DNA-dependent RNA polymerase activities increased immediately after infection. The major distribution of RNA polymerase classes shifted from class II to class I during infection.
Biogenic amines are formed in foods as a result of amino acid decarboxylation catalyzed by bacterial enzymes. When consumed in sufficient quantities, these compounds will cause headache, hypertension, fever, and heart failure. Technologies such as vacuum packaging and carbon dioxide-modified
Exposure of Chinese hamster ovary cells to the enzyme inhibitors methylglyoxal bis(guanylhydrazone and alpha-difluoromethylornithine (DFMO) results in increased sensitivity to hyperthermia. While methylglyoxal bis(guanylhydrazone) demonstrates pronounced cytotoxicity at moderate extracellular
Investigations with the melphalan-sensitive and -resistant human rhabdomyosarcoma xenografts TE-671 and TE-671 MR were performed to examine the effect of glutathione and polyamine modulation on thermosensitivity. Regimens of intraperitoneally injected and orally administered buthionine sulfoximine
Ten sessions of extracorporeal connection to a xenous (pig) spleen were conducted as part of combined treatment in 7 patients with urosepsis in combination with severe renal failure. The session lasted for 40 to 90 minutes. The blood volume, required to fill the spleen and the main vessels, was
Scrophularia buergeriana Miq. (figwort) contains a diverse group of bioactive natural products and is used to treat a variety of ailments, including fever, constipation, neuritis, and laryngitis. A transformation protocol was established for S. buergeriana using Agrobacterium tumefaciens.
Sensing and responding to environmental cues is a fundamental characteristic of bacterial physiology and virulence. Here we identify polyamines as novel environmental signals essential for virulence of Salmonella enterica serovar Typhimurium, a major intracellular pathogen and a model organism for
Biogenic amines have been reported in a variety of foods, such as fish, meat, cheese, vegetables, and wines. They are described as low molecular weight organic bases with aliphatic, aromatic, and heterocyclic structures. The most common biogenic amines found in foods are histamine, tyramine,