In most organisms, the heat-shock response involves increased heat-shock gene transcription. In Kinetoplastid protists, however, virtually all control of gene expression is post-transcriptional. Correspondingly, Trypanosoma brucei heat-shock protein 70 (HSP70) synthesis after heat shock depends on regulation of HSP70 mRNA turnover. We here show that the T. brucei CCCH zinc finger protein ZC3H11...

In this study the effects of heat shock on interleukin-1beta (IL-1)-induced inhibition of islet metabolic function were examined. Treatment of rat islets for 18 h with IL-1 results in a potent inhibition of glucose-stimulated insulin secretion. The inhibitory effects of IL-1 on insulin secretion are completely prevented if islets are pretreated for 60 min at 42 C before cytokine stimulation. He...

Possible mechanisms for the breakage of molecular crystals under high-intensity ultrasound were investigated using acetylsalicylic acid (aspirin) crystals as a model compound for active pharmaceutical ingredients. Surprisingly, kinetics experiments ruled out particle-particle collisions as a viable mechanism for sonofragmentation. Two other possible mechanisms (particle-horn and particle-wall c...

Previous research on sensitization in Aplysia was based entirely on unnatural noxious stimuli, usually electric shock, until our laboratory found that a natural noxious stimulus, a single sublethal lobster attack, causes short-term sensitization. We here extend that finding by demonstrating that multiple lobster attacks induce long-term sensitization (≥24 h) as well as similar, although not ide...

Using intense magnetic pressure, a method was developed to launch flyer plates to velocities in excess of 20 km/s. This technique was used to perform plate-impact, shock wave experiments on cryogenic liquid deuterium ( L-D(2)) to examine its high-pressure equation of state. Using an impedance matching method, Hugoniot measurements were obtained in the pressure range of 30-70 GPa. The results of...

This paper is concerned with the dependence structure of a multi-component, cumulative damage shock model, in which a system of components is subject to correlated shock damages and group repairs. A component fails when its cumulative damage exceeds a given threshold, and is then replaced by a new component. We incorporate a block maintenance schedule that simultaneously performs imperfect repa...

The heat-shock response is a key factor in diverse stress scenarios, ranging from hyperthermia to protein folding diseases. However, the complex dynamics of this physiological response have eluded mathematical modeling efforts. Although several computational models have attempted to characterize the heat-shock response, they were unable to model its dynamics across diverse experimental datasets...

Protein unfolding is a key step in the import of some proteins into mitochondria and chloroplasts and in the degradation of regulatory proteins by ATP-dependent proteases. In contrast to protein folding, the reverse process has remained largely uninvestigated until now. This review discusses recent discoveries on the mechanism of protein unfolding during translocation into mitochondria. The mit...

The heat shock response, which is accompanied by a rapid and robust upregulation of heat shock proteins (Hsps), is a highly conserved protection mechanism against protein-damaging stress. Hsp induction is mainly regulated at transcriptional level by stress-inducible heat shock factor 1 (HSF1). Upon activation, HSF1 trimerizes, binds to DNA, concentrates in the nuclear stress granules, and under...