Insect antifeedant properties of withanolides and related steroids from Solanaceae

Summary Physalis peruviana shrubs were not attacked by larvae ofSpodoptera littoralis. It was demonstrated that withanolide E, a steroid isolated fromP. peruviana, as well as several related steroids, have insect antifeedant properties.     

Effect of nitrate esters of androgen steroids on the succinate oxidase and NADH-Cytochrome C reductase activity of isolated rat liver mitochondria

Résumé Le testostérone et la 5-androstane-17-ol-3-one stimulent l'activité de la succinoxydase des mitochondries intactes et l'activité de la NADH-cytochrome-c-réductase des mitochondries à membranes lésées, extraites du foie du rat blanc. Les nitrates-esters des mÊmes stéroÏdes réduisent l'activité des deux enzymes.     

Alkaloid studies XXV. The structure of the Aspidosperma alkaloids cylindrocarpine and cylindrocarpidine

Zusammenfassung Die Strukturaufklärung von Cylindrocarpin (II) und Cylindrocarpidin (IV) zeigt, dass diese zwei Alkaloide die ersten Mitglieder der Aspidosperminfamilie (I) sind, in denen eine sauerstoffhaltige Seitenkette anstatt der gewöhnlichen C-5-Äthylgruppe vorliegt.

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Paper XXIV,T. Nakano, C. Djerassi, R. A. Corral, andO. O. Orazi, J. org. Chem., in press.

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Postdoctorate research fellow, 1958–1960.     

Comparison of the effects of atropine sulfate and procaine hydrochloride on nerve conduction

Zusammenfassung Die lokalanästhetische Wirksamkeit des Atropinsulfats wurde mit der des Novokains mittels Messung der Kinetik des Nervenimpulsblocks am isolierten Nervus ischiadicus des Frosches verglichen. Die relative Wirksamkeit des Atropinsulfats ist weniger als 120.     

An immunofluorescent method for identification of isolated thyrotropic cells

Summary A sensitive and specific immunofluorescent method for identification of thyrotropic cells was developed. The TSH-producing cells were found to be heterogenic in their morphology and intensity of staining.     

Methods for determining ploidy in amphibians: Nucleolar number and erythrocyte size

Summary Diploid and triploidXenopus can be easily and reliably distinguished by the size of their erythrocytes. This method has several advantages over other methods, such as counting metaphase chromosomes and counting nucleoli. One problem with the latter method is the reduction in cells with a full complement of nucleoli when regenerating tissue is used.Research supported by NIH grant EY 01662.     

Respiratory control in liver mitochondria of rats hosting the walker 256 carcinoma tumor.

The decrease in the respiratory control ratio of mitochondria is a first order process when these organelles are incubated in isotonic sucrose. Furthermore, the initial respiratory control ratios and the rates of loss in respiratory control in liver mitochondria from rats hosting the Walker 256 carcinoma are not significantly different form the same properties of mitochondria from untreated animals.