lnillbition experiments with paraoxon revealed two types of acetylcholinesterases in Panagrellus redivivus i.e. a fast (F-component) and a slow reacting component (S-component). The F-component was thermostable and inactivated by Triton-X100, while the S-component was thermolabile and insensitive for Triton-X-100. The bimolecular rate constant for inhibition by paraoxon was 25.5 x 103 M-1min' f...

Dialyzable Leukocyte Extract (DLE) is an extract obtained from immune lymphocytes capable of transferring antigenspecific information for cell-mediated immunity (CMI) from an immunized donor to a naïve recipient. Those products, also called Transfer Factors (TF), are peptides of 3500-6000 kDa in molecular weight; light yellow fluid with pH 6.5-7.0, composed of oligoribonucleotides attached a pe...

Evidence suggests that the small chloroplast heat-shock protein (Hsp) is involved in plant thermotolerance but its site of action is unknown. Functional disruption of this Hsp using anti-Hsp antibodies or addition of purified Hsp to chloroplasts indicated that (a) this Hsp protects thermolabile photosystem II and, consequently, whole-chain electron transport during heat stress; and (b) this Hsp...

A rapid assay for retroviral reverse transcriptase activity released into the culture medium by infected cells was developed. With the assay, 4,000 clonally infected cell lines could be tested in a few hours. We have adapted the assay for use as a screen for the detection of spontaneous viral mutants. Mutants of Moloney murine leukemia virus have been isolated which (i) produce a thermolabile r...

An enzyme with the characteristics of classical renin was isolated from brain extracts of nephrectomized dogs. This enzyme is thermolabile, nondialyzable, and forms a vasoconstrictive material when incubated with renin plasma substrate at pH 7. A short lasting pressor activity was also found in brain extracts of dogs and rats. This activity was due to a substance identified by chemical and phar...

Vacuum freeze-drying has been considered the best dehydration process for thermolabile products because it reduces nutritional and sensorial degradation. As water is removed from a pre-frozen product, a porous structure is formed, which results in a dehydrated product that has better properties when rehydrated.1 This technique springs up rapidly along with the development of refrigeration, vacu...