Computer simulation of protein folding.

A new and very simple representation of protein conformations has been used together with energy minimisation and thermalisation to simulate protein folding. Under certain conditions, the method succeeds in "renaturing" bovine pancreatic trypsin inhibitor from an open-chain conformation into a folded conformation close to that of the native molecule.     

Early investigations on the effect of methyl mercuric chloride upon DMN-acute hepatotoxicity

Summary Acute toxicity induced by DMN was partially prevented by previously administering methyl mercuric chloride (MMC), a chemical inhibitor of the drug metabolizing enzyme system (DMES). We have studied the early changes occurring during the course of DMN-intoxication, namely disaggregation of polysomal profiles and necrosis, evaluated morphologically and by the release of S-GPT.This work was supported by Consiglio Nazionale delle Ricerche, Roma, Italy.     

Serum enzyme activities in the African elephant (Loxodonta africana)

Summary The serum activities of aspartate aminotransferase, alanine aminotransferase, -hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed.     

Effects of physalaemin, a vaso-active peptide from amphibian skin, on the excitability of an identifiable molluscan giant neurone of Achatina fulica Férussac.

We examined effects of several vasoactive peptides (substance P, physalaemin, neurotensin, bradykinin, angiotensin etc.) on the excitability of molluscan giant neurones identified in the subesophageal ganglia of Achatina fulica Férussac. Of these peptides, only physalaemin showed a remarkable excitatory effect on a giant tonically autoactive neurone.     

Effect of the extracts from Aristolochia indica Linn. on interception in female mice.

The crude petroleum ether, chloroform and alcoholic extracts from the roots of Aristolochia indica (Linn.) showed 100% interceptive activity in mature female mice at the single dose of 100 mg/kg body wt. The follow-up studies with the chloroform extract showed the most significant effect in the basic part and two acidic fractions at the single dose levels of 50 mg/kg body wt. No toxic effect was observed at the dose levels used.