Thermoperiodic information and the induction of diapause in Pieris brassicae L]

When exposed their whole larval life to a 24 h. thermoperiodic cycle in constant darkness, individuals of Pieris brassicae L. give diapausing or non-diapausing pupae according to the length of the cold and warm sequences. The curve of thermoperiodic induction is similar to the photoperiodic curve.     

Elongated chromosomes in Pieris brassicae L. (Lepidoptera,Pieridae) after treatment with colchicine

Summary Elongated chromosomes, which can be arranged into karyograms on the basis of length, were obtained for the first time in Pieris brassicae L. (Pieridae: Lepidoptera).Acknowledgments. We wish to express our sincere thanks to Dr A. K. Datta-Gupta, Professor and Head of our Department, for providing the research facilities and for encouragement.     

On the structure of pterobilin,the blue pigment ofPieris brassicae

Zusammenfassung Aus dem Tegument von Raupen des Kohlweisslings (Pieris brassicae) wird das bereits früher beschriebene Pterobilin isoliert, das auf Grund seiner Abbauprodukte und der chromatographischen und spektralen Eigenschaften als Biliverdin-IX identifiziert wird.     

Juvenile hormone titers in penultimate and last instar larvae ofPieris brassicae andBarathra brassicae,in relation to the effect of juvenoid application

Summary JH titer was determined in the haemolymph of penultimate and last instar larvae ofPieris brassicae L. andBarathra brassicae L. The differences we observed were consistent with physiological differences between the two species.The authors feel indebted to Prof.V. J. Brookes for useful comments.     

Occurrence of monocentric chromosomes inPieris brassicae L. (Lepidoptera,Pieridae)

Summary Monocentric chromosomes with localized kinetochores were obtained inPieris brassicae (Lepidoptera, Pieridae) by using colchicine treatment and air-drying method.We wish to express our thanks to Dr A.K. Datta-Gupta, Professor and Head of our Department for providing the research facilities and for encouragement.     

A thymidine-induced sex-linked,sex-limited temperature-sensitive lethal and the significance of modifier genes inDrosophila melanogaster

Zusammenfassung BeiDrosophila melanogaster wurde ein temperaturabhängiger Letalfaktor gefunden. Die Temperaturabhängigkeit der Manifestation wird mit dem Vorhandensein von Modifikationsgenen erklärt.     

Nitroġenous excretory products of tobacco hornworm,Manduca sexta (L.)

Zusammenfassung Die stickstoffhaltigen Exkretionsprodukte von Raupen vonManduca sexta L. wurden papierchromatographisch analysiert. Die wichtigsten ausscheidungsprodukte sind Harns?ure und Allantoin: Harnstoff wird nur in Spuren ausgeschieden.      

Adenosine promoted accumulation of adenosine 3',5'-monophosphate in rabbit vagus nerve.

Desheathed rabbit vagus nerve has been found to form cyclic AMP when incubated with adenosine. This accumulation of cyclic AMP is inhibited by theophylline but not by antiadrenergic agents, anticholinergic agents or local anaesthetics. Depolarizing media are not able to promote cyclic AMP accumulation in this preparation.     

Isolation from rat brain of a metabolic product,desmethylimipramine, that mediates the antidepressant activity of imipramine (Tofranil)

Zusammenfassung Nach Verabreichung von Imipramin (Tofranil) wurde aus dem Gehirn von Ratten Desmethylimipramin, das N-Monomethylderivat, isoliert. Dieser Metabolit beziehungsweise dessen Anreicherungin vivo scheint für die antidepressive Wirkung von Imipramin verantwortlich zu sein.

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Presented in part as an abstract in Fed. Proc.20, 321 (1961). Some of the material in this communication is taken from a dissertation byJ. V. Dingell to be submitted to the Graduate School of Georgetown University in partial fulfillment of the requirements for the degree of Doctor of Philosophy.     

(+)-Tetrahydro-6-heneicosyl-2H-pyran-2-one,a natural product from Heliotropium curassavicum Linn

Summary The hitherto unknown lactone of -hydroxy hexacosanoic acid, tetrahydro-6-heneicosyl-2H-pyran-2-one has been isolated from hexane extracts of Heliotropium curassavicum Linn.We are grateful to the University Grants commission, New Delhi for award of Junior Research Fellowships to S.M. and P.K., and to Dr C. C. J. Culvenor, CSIRO (Australia) for the gc-ms data.     

Bromal,the product of reaction of aspartic acid with N-bromosuccinimide

Zusammenfassung Bromal wurde als ein Endprodukt der Reaktion zwischen Asparginsäure und N-Bromsuccinimid identifiziert und die antibakterielle Aktivität dieser Verbindung gegenüber einigen Mikroorganismen geprüft.     

Oxygenation of a dipyrromethene model for bilirubin: Formation of a singlet oxygen-like product

Summary An oxodipyrromethene model compound for bilirubin is found to undergo oxidation to a blue tetrapyrrole and a water-propentdyopent on a silica gel thin layer chromatography plate. The reaction involves ground state oxygen and requires silica gel, although the propentdyopent is an expected product from reaction with singlet oxygen.The authors wish to thank the National Science Foundation for generous support of this work. We also thank Mr.Richard Gillespie and Ms.Elizabeth Irwin for running the high resolution mass spectra.     

Anticonvulsant activity of farnesylacetone epoxide—a novel marine natural product

Summary A marine natural product, farnesylacetone epoxide, which is chemically related to juvenile hormone, has anticonvulsant properties at nonsedative doses in mice.     

Pyrolysis of cannabidiol. Structure elucidation of a major pyrolytic conversion product

Summary Pyrolysis of cannabidiol, one of the major constituents of Cannabis sativa, yields a mixture of components. Next to previously identified products, a major conversion product has now been isolated and identified. The unusual and stereospecific route of formation of this compound with altered chromophore is discussed.Acknowledgments. This research was supported by the Dutch Department of Public Health and Environmental Hygienics. Thanks are due to R. D. van Ooyen who provided technical assistance, Dr M. J. A. de Bie and Dr W. Heerma for valuable discussions, Drs J. W. Marsman and Ir T. Spoormaker for performing PMR experiments.