Chiral influence of sex pheromonal substances on responses of the male American cockroach

Summary In order to elucidate the roles of optical enantiomers of sex pheromonal substances of the American cockroach, behavioral assays with a single enantiomer and with mixtures of enantiomers of sex pheromone mimics were carried out. Inactive enantiomers [(–)-enantiomers] had no influence on the potency of enantiomers active as sex pheromones [(+)-enantiomers]. By analysis of the results from EAG recordings with single and mixed sample of the enantiomers, it was confirmed that (–)-enantiomers did not react with the sex pheromone receptors which are responsive to (+)-enantiomers.We acknowledge technical assistance from Miss R. Kimura.     

Reduction of ferricytochrome c by human red cells

Summary Human red cells reduced extracellular ferricytochrome c to ferrocytochrome c under various conditions, suggesting that ferricytochrome c reducing systems are present at the outer surface of the red cell membrane.     

Über die Adsorptionskraft der Pektine in organischen Lösungsmitteln

Summary Pectin does not present any surface activities in organic solvents. An eventual fixation of some substances is based on mutual chemical affinity.     

Differences in the dexoxyribonucleoprotein complex of normal and leukemic human lymphocytes

Riassunto Gli autori hanno determinato con metodo citofotometrico nel visibile il contenuto di acido desossiribonucleico (DNA) e di proteina istonica nei linfociti di 4 soggetti normali e di 4 pazienti affetti da leucosi linfatica.I valori del DNA sono apparsi uguali nelle cellule normali e in quelle leucemiche, i valori dell'istone sono risultati in queste ultime superiori alla norma, onde il rapporto DNA/istone risulta essere nei linfociti leucemici inferiore a quello dei linfociti normali.     

Fusaric acid production byFusarium orthoceras in vitro

Zusammenfassung Durch biologische und papierchromatographische Methoden konnte nachgewiesen werden, dassauchFusarium orthoceras den Welkestoff Fusarinsäure in die Kulturflüssigkeit abscheidet. Unter den angegebenen Bedingungen werden relativ grosse Mengen dieses Stoffes gebildet (300 mg/l gegenüber 65 mg/l durchF. moniliforme und 35 mg/l durchF. vasinfectum).     

The influence of chronic nicotine treatment on stress-induced gastric ulceration and emptying rate in rats.

Ten-day treatment with nicotine (5, 25 or 50 micrograms/ml drinking water) dose-dependently intensified gastric ulceration induced by cold-restraint, and emptying rate. Stomach contractions produced by graded doses of bethanechol i.v. were elevated further by nicotine treatment. It is suggested that chronic nicotine administration produces hypersensitivity of the gastric muscarinic receptors; stomach hypermotility contributes to the ulcer-worsening action of the alkaloid.     

The endocrine nature of the paraganglia of man

Summary Brightly fluorescent paraganglia were found in the retroperitoneal tissue of adult man. The histofluorescence properties of the paraganglia indicate the presence of tryptophyl peptides, which might be of endocrine importance.     

The effect of urethane and pentobarbital anaesthesia and hepatic portal vein catheterization on liver blood flow in the rat

Summary The effect of urethane and pentobarbital anaesthesia and hepatic portal vein catheterization on liver blood flow was investigated in the rat. Liver blood flow with pentobarbital anaesthesia was 40% greater than with urethane. Hepatic portal vein catheterization had no effect under pentobarbital anaesthesia whereas it produced an 18% fall in liver blood flow with urethane.Acknowledgments. This work was supported by grants from ICI Pharmaceuticals and Mersey Regional Health Authority (Research Scheme No. 338). We wish to thank Mr P.J. Roberts for much skilled assistance and Evans Medical Ltd for the kind gift of drugs.