The kinetics of thermotolerance in a human malignant melanoma grown in athymic mice (BALB/c/nu/nu/BOM) was studied. Local hyperthermia was given by immersing the tumor-bearing leg of the mice into a thermostatically regulated water bath. The tumors were exposed to a priming heat dose of 42.5 degrees for 30 min and, at different fractionation intervals, to graded heat doses at 42.5 degrees. Tumo...

Cells exposed to heat or other types of stressors transiently synthesize a group of proteins known as heat shock proteins (HSPs). A nonlethal heat treatment can elicit in the cells an ability to resist subsequent lethal heat treatments. We report here that a novel benzylidene lactam compound, KNK437, dose-dependently inhibited the acquisition of thermotolerance and the induction of various HSPs...

Species in the virilis group of Drosophila (fruit flies), which overlap or replace one another along climatic gradients, exhibit corresponding differences in basal thermotolerance, inducible thermotolerance and the heat-shock response. The low-latitude species D. virilis exceeds the high-latitude species D. lummei in these measures of thermotolerance, the temperature threshold for heat-shock fa...

Traits of physiological thermotolerance are commonly measured in the laboratory as predictors of the field success of ectotherms at unfavourable temperatures (e.g. during harsh winters, heatwaves, or under conditions of predicted global warming). Due to being more complicated to measure, behavioural thermoregulation is less commonly studied, although both physiology and behaviour interact to ex...

A heat-conditioning treatment of 10 mm at 45°followed by 370 incubation resulted in maximal thermotolerance 8 hr later. The D@of the heat survival curve increased from 4.5 mm (control) to 19.8 mm at 45°.Two heat-conditioning treatments (10 mm at 45°+ 4 hr at 37°+ 15 mm at 45°)resulted in a higher thermotolerance maximum (D@= 26.7 mm) 8 hr after the second • conditioning treatment. In com...

In the yeast, Saccharomyces cerevisiae, the disaccharide trehalose is a stress-related metabolite that accumulates upon exposure of cells to heat shock or a variety of non-heat inducers of the stress response. Here, we describe the influence of mutations in individual heat-shock-protein genes on trehalose metabolism. A strain mutated in three proteins of the SSA subfamily of 70-kDa heat-shock p...

Three murine lymphoma cell lines, CH1, a B-cell lymphoma, and VL3 and RDM4, both T-cell lymphomas, were tested for their ability to induce heat shock protein synthesis and thermotolerance after heat shock. All three lines could develop thermotolerance, but the persistence of tolerance was less than can be measured in nonlymphoid cell lines. Analysis of protein synthesis patterns by one-dimensio...

Three murine lymphoma cell lines, CHI, a B-cell lymphoma, and VL3 and RDM4, both T-cell lymphomas, were tested for their ability to induce heat shock protein synthesis and thermotolerance after heat shock. All three lines could develop thermotolerance, but the persistence of tolerance was less than can be measured in nonlymphoid cell lines. Analysis of protein synthesis patterns by one-dimensio...

Mouse fibroblast LM cells have been modified with respect to the content of polyunsaturated fatty acyl (PUFA) chains of the membrane phospholipids. The membranes of the modified cells were enriched in PUFA chains and were more fluid as compared to the normal cells, as judged by fluorescence polarization mea surements. The thermosensitivity of the PUFA-substituted cells was enhanced. Thermotoler...