Physical Analysis of Heat-induced Cellular Inactivation

Inactivation of imprinted genes induced by cellular stress and tumorigenesis.

Cellular proliferation under stressful conditions may result in permanent genetic and epigenetic changes. Using primary mouse embryonic fibroblasts, we have completed a screening test to identify gene expression changes triggered when cells proliferate under stress. In this manner, we have discovered a novel phenomenon that consists of the rapid and coordinated silencing of genes subject to imp...

Inactivation of heat shock factor Hsf4 induces cellular senescence and suppresses tumorigenesis in vivo.

Studies suggest that Hsf4 expression correlates with its role in cell growth and differentiation. However, the role of Hsf4 in tumorigenesis in vivo remains unexplored. In this article, we provide evidence that absence of the Hsf4 gene suppresses evolution of spontaneous tumors arising in p53- or Arf-deficient mice. Furthermore, deletion of hsf4 alters the tumor spectrum by significantly inhibi...

Physical Aspects of Reversible Inactivation

Most early investigations of the chemistry of endotoxins were limited to gross analyses. I t soon became apparent that subtler means of degradation, such as enzymes, were necessary to determine structural configurations and intramolecular relationships within the endotoxin complex. Just such a subtle endotoxin-degrading system was suggested by the observation of Hegemann (1954) that human plasm...

The Physical Inactivation of Invertase.

Heat resistance and mechanism of heat inactivation in thermophilic campylobacters.

The heat resistance of Campylobacter jejuni strains AR6 and L51 and the heat resistance of Campylobacter coli strains DR4 and L6 were measured over the temperature range from 50 to 60 degrees C by two methods. Isothermal measurements yielded D55 values in the range from 4.6 to 6.6 min and z values in the range from 5.5 to 6.3 degrees C. Dynamic measurements using differential scanning calorimet...