Properties of Mycobacteriophage C2

Résumé Le mycobactériophage C2 a une morphologie typique tête-queue, la longueur de la tête étant de 60 nm et celle de la queue de 200 nm. Le génome du phage est un acide désoxyribonucléique. Le phage C2 joue un rôle important dans la génétique mycobactérienne.

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Supported by grant No. MA-2718 from M.R.C., Canada. We thank Dr. E.Mankiewicz for her suggestions and samples, and Mr. L.Berthiaume for assistance in electron microscopy. One of us (J.M.), presently at Dept. Microbiology, University of Ottawa, is a M.R.C. Fellow.     

Establishment of a cell line (XTC-2) from the South African clawed toad,Xenopus laevis

Résumé On décrit une méthode pour l'établissement d'une culture de cellules du crapaud a griffes sudafricain,Xenopus laevis, afin de l'infecter avec des arbovirus. Les cellules (XTC-2) ont subi une culture continue pendant 3 ans. Elles ont un nombre diploïde de chromosomes. Elles furent cultivées aux températures de 22°C et de 28°C dans un milieu de culture dilué de NCTC 109 avec 10% de sérum de veau foetal.

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We thank ProfessorD. S. Bertram, Director of the Department of Entomology at the School, for his continued interest; Mr.A. O. Langi for technical assistance and Dr.L. Hamilton, Middlesex Hospital Medical School, London, for supplying theXenopus tadpoles. We are especially grateful to the Wellcome Research Laboratories, Beckenham, for supplying medium NCTC 109, and to Mr.D. J. Richmond of the Laboratories for responding to our request for medium promptly and willingly. The work is supported in part by a grant from the Medical Research Council of Great Britain.     

A chromosome mutation affecting the number of nucleoli inXenopus borealis Parker

Résumé L'examen cytologique de la descendance de 2Xenopus borealis révéla 50% d'individus dotés de noyaux à 1 et 2 nucléoles (situation normale) et 50% à 1, 2 et 3 nucléoles. Le caryotype de ces derniers démontra la présence de 3 organisateurs nucléolaires, au lieu de 2, l'origine de l'élément supplémentaire relevant d'une translocation réciproque entre 4 et 7.

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Supported by a grant (No. 3.60.68) from the Fonds national suisse de la Recherche Scientifique and the George and Antoine Claraz donation.

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Unpublished research in this laboratory has shown thatXenopus laevis borealis (Parker) is a species on its own right and we propose to name itXenopus borealis (Parker).

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Material collected byFischberg andKobel, who express their gratitude to the Fisheries and Game Dept. of Kenya for permission to collect frogs of the genusXenopus.

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Acknowledgments. The authors wish to thank Mrs.J. Tymowska and MissE. Ackermann for their technical advice; they are grateful to Mr.J. Jackson, MissM. C. Payot, MissL. Ricard and Mr.P. Grutter for their assistance and useful help.     

The membrane expansion theory of anesthesia: Direct evidence using ethanol and a high-precision density meter

Résumé Utilisant une nouvelle mesure de densité, de haute précision, on étudia l'effet de l'éthanol sur le poids spécifique des membranes des érythrocytes et des synaptosomes. La concentration de l'éthanol qui produit l'anesthésie générale (0.05M) étendit le volume spécifique des membranes à 0.5–0.6%. Aux concentrations de l'éthanol qui produisent l'anesthésie locale (1M) l'extension du volume spécifique fut de 3 et 6%. Ces résultats supportent la théorie de l'extension des membranes par les anesthétiques et suggèrent que l'extension des constituants protéinés des membranes est plus importante que celle des constituants lipides.

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Acknowledgment. I thank Dr.H. Schneider (National Research Council Ottawa, Canada) for suggesting the use of the density meter, and Ms.M. Chau-Wong, ProfessorK. Yates and Dr.R. McLelland for their help. Supported by Addiction Research Foundation of Ontario, the Ontario Mental Health Foundation, and the Medical Research Council of Canada (grant No. MT-2951).     

On the biosynthesis of neoflavanoids

Résumé Les hypotheses sur le mécanisme de la biosynthèse des néoflavanoïdes sont discutées sur la base de résultats de nos expériences d'incorporation dans leCalophyllum inophyllum.

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We thank the C.E.A. (Saclay) for a grant towards the purchase of labelled compounds, Mr.G. Henry for technical collaboration and the Comité de l'Accueil du Phytotron for culture facilities.     

Induction of aryl hydrocarbon hydroxylase in the lungs of mice in response to cigarette smoke

Résumé L'absorption, par inhalation, de la fumée de cigarette, produit une accélération rapide de l'activité de l'aryl hydrocarbure hydroxylase dans les poumons de la souris. Après une exposition de 4 semaines, ces niveaux sont 3–4 fois plus élevés que ceux du contrôle. Dans le foie, ces actions se manifestent d'une facon beaucoup plus faible et lente.

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Supported by a grant from the Australian Tobacco Research Foundation. The authors thank L. Roberts andM. B. Hart for technical assistance.     

Dynamics of estrogen binding by uterine cells in vivo

Summary The dynamics of the in vivo binding and release of tritiated estradiol in different uterine cell types are described. The very early binding of estrogens by the cytosol-nuclear and the eosinophil receptor systems is in accordance with the hypothesis that some estrogenic effects are mediated by these receptor systems.Acknowledgments. This work was supported in part by grant 2015 from the Servicio Técnico de Desarrollo Científico y Creación Artística of the University of Chile to the Laboratory of Experimental Endocrinology, Department of Experimental Morphology, University of Chile Medical School, by a Population Council Fellowship to Dr A. Tchernitchin from 1970 to 1972, by a Rockefeller Foundation grant to the Laboratories of Reproductive Biology, University of North Carolina Medical School, and by USPHS grant HD00371 to the Children's Hospital of Philadelphia. We wish to thank Drs W. E. Stumpf (Laboratories of Reproductive Biology, University of North Carolina Medical School) and A. M. Bongiovanni (Children's Hospital of Philadelphia) for the facilities available.     

Effects of glycine and serine on serine hydroxymethyltransferase levels in logarithmic cultures ofNeurospora crassa wild type andSer-1 mutant

Résumé Dans un milieu minimal la glycine et la sérine, ajoutées en concentrations physiologiques, augmentent le taux de la sérine-hydroxyméthyltransférase durant la croissance logarithmique duNeurospora crassa. La glycine influence également la synthèse de cet enzyme chez le mutantSer-1 deNeurospora. Ainsi la glycine exogène exerce une régulation de la sérine-hydroxyméthyltransférase et cet enzyme joue un rôle possible dans la synthèse de la sérine dans cet organisme en phase logarithmique de croissance.

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Acknowledgements. This investigation was supported by grant No. 3.540.71 from the Fond National Suisse de la Recherche Scientifique. E.A.C. was the recipient of a National Research Council of Canada travel fellowship. The authors thank MlleMartine Gourjon for excellent technical assistance.     

Two novel metabolites ofAspergillus fonsecaeus

Resumen DelAspergillus fonsecaeus (N. R. R. L. 67, O 16-1) se han aislado dos nuevos pigmentos que fueron identificados como monometil éteres de la fonsecina y de la rubrofusarina, respectivamente.

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Acknowledgement. The authors thank Prof.S. Shibata of Tokio University for reference compound, the Cátedra de Microbiologia Industrial of their Faculty for fermentation work and the Consejo Nacional de Investigaciones Cientificas y Técnicas for a grant.     

Lactate dehydrogenase polymorphism inMus musculus L. andMus spretus Lataste

Summary First variation at theLdh-A locus and a new allele at theLdh-B locus are reported in aM. musculus population dimorphic at theLdh-A locus and in aM. spretus population trimorphic at theLdh-B locus.Acknowledgments. This study was achieved with the technical assistance of J. Catalan. We thank N. Pasteur and F. Bonhomme for useful comments. This work was supported by the Université Montpellier 2 (service électrophorèse du Centre de Recherche sur l'Evolution et ses Mécanismes), the Ecole Pratique des Hautes Etudes and the Centre National de la Recherche Scientifique (ERA 261).     

Heart tissue catecholamines in the greyRatus norvegicus

Résumé Le taux des catécholamines du myocarde a été dosé chez le rat sauvage vivant dans la nature et chez le rat de la même espèce vivant dans des conditions de confinement en laboratoire. Chez l'animal élevé en laboratoire le taux des catécholamines est significativement plus élevé que chez son homologue vivant dans la nature.

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The authors wish to thank Mr.F. Vigneron for providing them with wild rats and raising the grey labRatus norvegicus.

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Partially supported by a grant of the Fonds National de la Recherche Scientifique of Belgium.     

Fluorinated analogs of insect sex pheromones

Summary The syntheses of fluorinated mimics of pheromones ofSpodoptera littoralis, Diparopsis castanea, Laspeyresia pomonella, Bombyx mori andThaumetopoea pityocampa are described. These analogs showed biological activities similar to those of the natural pheromones in laboratory assays (EAG).We gratefully acknowledge Comisión Asesora de Investigación Cientifica y Técnica for financial support (Grant No. 3296/79) and Consejo Superior de Investigaciones Cientificas for predoctoral and postdoctoral fellowship (to G.F. and M.R.). We also thank Mr J. Baltá and Ms R. Murgó for their collaboration in the EAG work.     

Insect antifeedant terpenes,hot-tasting to humans

Summary Four dialdehyde sesquiterpenoids (1–4) isolated from East AfricanWarburgia plants exhibit powerful antifeeding activity for larvae of the armyworms,Spodoptera exempta andS. littoralis. The hotness of these sesquiterpenes is associated with this activity. The specific absolute stereochemistry of these antifeedants appears to govern the hotness of the taste.The authors are grateful to Proff. K. Nakanishi, A.S. Kende and T. Kubota for their interest and valuable discussion. Succulatal was provided by Dr. Y. Asakawa. This work was initiated during the stay of I.K. at the International Center of Insect Physiology and Ecology, Nairobi, Kenya. We also thank Mr A. Chapya for technical assistance.     

Induction of deoxyribonucleic acid degradation inEscherichia coli by ozone

Summary Cell survival and deoxyribonucleic acid (DNA) degradation were measured for wild-typeEscherichia coli B251 cells after exposure to different concentrations of ozone. The results show that extensive breakdown of DNA occurs after ozonation and that the extent of ozone-induced DNA degradation generally correlates with the colony-forming ability of the cells.We thank Dr M.J. d'Aoust for supplying laboratory facilities. This work was jointly sponsored by the National Research Council of Canada, the Ministère de l'Education du Québec, and funds from the Université de Montréal. One of us (C.H.) acknowledges a postgraduate scholarship from the NRC of Canada.     

Some observations on bipolar filaments formed by non-muscle myosins

Summary Adrenal medullary and retinal myosins formed bipolar filaments in vitro. These filaments showed features suggesting flexibility in the rod region of the myosin molecules composing such filaments; in certain cases the myosin heads spread away from the filament backbone, in others the backbone itself was twisted. In addition the bare central backbone showed transverse striations.We thank G. Devilliers for assistance with electron microscopy, D. Thiersé for technical assistance during purification of adrenal medulla myosin and Professor P. Mandel for his interest and support J.E.H. gratefully acknowledges receipt of a Royal Society European Exchange Fellowship and a grant from INSERM. N.V. is chargée de recherches au CNRS, D.A. is chargé de recherches à l'INSERM.     

Genetic control and modifications of peroxidase pattern in two species ofNicotiana and their interspecific hybrid

Summary The peroxidase patterns ofNicotiana suaveolens, N. glutinosa and their interspecific hybrid have been studied, and their possible genetic control analyzed. Modifications of the isozymatic pattern along the plant have been observed.Acknowledgments. The authors thank Prof. J.R. Lacadena and Dr M. Pérez de la Vega for their valuable advice.     

Structural coupling between pancreatic islet cells

Résumé Ce travail décrit la présence de spécialisations des membranes plasmatiques entre les cellules endocrines des îlots de Langerhans chez le rat. Ces spécialisations sont révélées par le cryodécapage («freeze-etching») et apparaissent sous la forme de nexus («gap-junctions») ou de jonctions serrées («tight-junctions»). Elles représentent probablement la base structurale d'un couplage ionique et métabolique entre les cellules endocrines.

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We thank M. Sidler-Ansermet and M. Bernard for technical assistance. This work was supported in part by grants from Fonds National Suisse de la Recherche Scientifique and by a grant-in-aid from Hoechst-Pharmaceuticals, Frankfurt-Hoechst, Germany. Preliminary findings (L. Orci, A. E. Lambert, Y. Kanazawa, W. Stauffacher, Ch.Rouiller andA. E. Renold, Diabetes20, 326, 1971) and the present work (L. Orci, R. H. Unger andA. E. Renold, Abstr. 7th ann. meetind Europ. Soc. Clin. Invest., Rotterdam, 1973, p. 157) have been reported in an abstract form.     

Epidermal sensitivity to hypoxia in the lugworm

Summary Physiological and anatomical data support the idea that in the caudal epidermis of the lugworm,Arenicola marina (L.), there are chemoreceptors detecting variations of oxygen partial pressure in the ambient water.This research was partly supported by a C.N.R.S. grant, AI No. 582 085. We thank Dr P. Dejours and Dr J. Taxi for helpful comments and discussion, Mrs S. Dejours for editing the English of this paper, M.F. Baucher, A. Dorme, F. Kleinbauer, the staff of the Station Biologique de Roscoff and the Service de Microscopie Electronique, C.N.R.S., boulevard Raspail, Paris, for technical assistance.     

Uptake of alanine,phenylalanine and tyrosine by L1210 cells at 4°C: Possible effect of lipid solubility

Résumé L'introduction d'un groupe phényl facilite grandement le transfert del-alanine tandis que l'hydroxylation du groupe phényl diminue la facilité de transfert.

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Supported in part by a grant from Charles H. Hood Dairy Foundation. I thank Dr.John J. McCormack, and Dr.A. H. Schein, University of Vermont, for helpful discussions.     

Isolation of quercetin 3,7,3′,4′-tetrasulphate fromFlaveria bidentis L. Otto Kuntze

Résumé A partir de l'extrait des feuilles deFlaveria bidentis (Compositae), on peut obtenir le 3,7, 3, 4 tétrasulphate de quercétine. Sa constitution a été déterminée par des méthodes physiques et chimiques.

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Acknowledgments. We thank ProfessorsV. Deulofeu (Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires) andR. Caputto (Facultad de Ciencias Químicas, Univ. Nac. de Cordoba) for the very useful discussions. To Agron. A.Hunziker (Museum of Botany, Universidad Nacional de Córdoba) for the taxonomic classification. To Dr.H. M. Horowitz (Pasadena, California) for the authentic sample of Azaleatine.