Cone mosaics in a teleost retina: Changes during light and dark adaptation

Summary The square mosaic pattern of retinal cones in the guppy,Poecilia reticulata, changes during dark adaptation into a row mosaic. The functional significance of this change is discussed.Thanks are due to Dr A. Yacob, Biology Department, Mosul University, for supplying the photomicrograph for figure 2A, and to Dr C. Wise, Department of Zoology, University College, Dublin, and B. A. Collins, The Marine Biological Laboratory, Woods Hole, for technical assistance.     

Mutation inSchizophyllum commune for resistance top-fluorophenylalanine

Résumé Isolement de mutants résistants à lap-fluorophenylalanine et son analyse chezSchizophyllum communis.

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This is a part of the Ph. D. work carried at the Department of Botany, Queen Mary College, London University, and the author wishes to express here grateful appreciation to ProfessorE. A. Bevan for his guidance in this study.     

Division ofEntamoeba invadens Rodhain, 1934, in cultures

Zusammenfassung BeiEntamoeba invadens wurde eine ungleiche zellplasmatische Teilung beobachtet. Ein entsprechender Teilungsmodus gilt auch fürE. ranarum undE. moshkovskii.

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This work was done in the Department of Zoology, University of London, King's College, London WC2, England.     

Inhibition of Ehrlich ascites carcinoma (EAC) growth by carbonyl iron

Summary Treatment of Ehrlich ascites carcinoma (EAC) cells with carbonyl iron (20 mg/ml) produces a significant decrease in growth rate of tumor inoculum both in Swiss and in C57BL/6 mice. Possible interaction of the carbonyl iron or Fe⁺⁺⁺ions with cell surface is suggested.Supported by a grant from the Consiglio Nazionale delle Ricerche.Acknowledgments. The authors are grateful to Dr M. M. Clynes (University College, Dublin, Ireland) for his helpful discussion.     

Effects of gonadal hormones on the lipid contents of the frogRana esculenta

Summary The effects of exogenous gonadal hormones on the lipid contents of the liver and ovary and also on water content in the frog,Rana esculenta, were studied. Estrogen treatment significantly enhanced, whereas testosterone treatment reduced, the lipid and cholesterol contents. Water content of the frogs increased significantly after treatment by either hormone.Acknowledgment. I wish to thank Dr Hussain Al-Adhub, College of Science for providing all necessary laboratory facillities. Present address: Physiology Laboratory, Department of Zoology, Patna University, Patna-80005, Bihar (India).     

Inhibitory action of dehydroepiandrosterone (DHEA) on fibroblast growth

Summary Dehydroepiandrosterone inhibits thymidine incorporation into human fibroblasts and may thus interfere with cellular growth.This investigation was supported in part by USPHS NIH training award AM 00329 and The New York State Health Research Council under contract #272.Acknowledgment. The authors wish to thank A. B. Rifkind, from the Department of Pharmacology at Cornell University Medical College for provision of skin biopsies.     

Glutamine synthetase activity in subdivisions of brain of the shark,Squalus acanthias

Summary Specific activity of glutamine synthetase inSqualus acanthias (spiny dogfish) central nervous system regions was highest in the cerebellum and lowest in the spinal cord. The levels of activity may relate to the excitability of each region by regulating the glutamate pool.Publication No. 14 from the Laboratory of Biochemical Ecology. Contribution No. 527, College of Fisheries, University of Washington. This work was supported in part by a fellowship from the national Wildlife Federation and a Pacific Fisheries Biologists' scholarship to J.T.W.     

Correlation between acidic phospholipids and serotonin and between lysolecithin and dopamine in ganglia of the marine mussel,Mytilus edulis

Summary These studies have demonstrated a positive correlation between the acidic phospholipids and the serotonin content and between the lysolecithin and the dopamine content in the cerebral, pedal and visceral ganglia ofMytilus edulis. These relationships were further supported by experiments utilizing 6-hydroxydopamine and 5,6-dihydroxytryptamine.This study was partially supported by USPHS grant NS 10845 to Dr E. Aiello of Fordham University.Presently at Medgar Evers College of C.U.N.Y., Brooklyn, N.Y. 11225.     

The effect of leafhopper infestation on the respiration of castor bean varieties in relation to their resistance toEmpoasca flavescens (F.) (Homoptera: Jassidae)

Zusammenfassung Die Saugtätigkeit der JassideEmpoasca flavescens (F.) führte zu einer um 44% gesteigerten Respiration von geschädigten, anfälligen Rizinuspflanzen (Ricinus communis L.) im Vergleich zu 11.6% und 3.7% bei Pflanzen einer toleranten und resistenten Sorte. Diese Zunahme war bei der anfälligen Sorte verknüpft mit einer gesteigerten Anhäufung von Rohrzucker, Gesamtstickstoff und Gesamtaminosäuregehalt.

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This study formed part of the Doctoral Thesis submitted to the University of Madras and financial support was given by the Council of Scientific and Industrial Research, Government of India, New Delhi. Grateful appreciation is extended to Prof. A. R.Seshadri, Agricultural College and Research Institute, Coimbatore, India and Prof. R. H.Painter, Kansas State University, Kansas, U.S.A. for their valuable suggestions made during the course of the study.     

On the inhibitory action of endosperm on germination ofCercis siliquastrum seeds

Summary The endosperm inhibits the growth of embryos isolated fromCercis siliquastrum seeds. The inhibitory activity is present in autoclaved homogenates as well as in homogenates remaining after an extraction with chloroform or isobutanol.Acknowledgment. The authors wish to thank Prof. E. Marré, Milan University, for his help in preparation of this paper.     

Changes in placental permeability to corticosterone and estradiol-17β toward the end of gestation in the rat

Summary Radioactivity in the fetal plasma 1 h after maternal injection of¹⁴C-4-corticosterone or¹⁴C-4-estradiol-17 on day 21 of gestation was markedly higher than that 1 h after injection on day 22. Radioactivity in the maternal plasma was not different on these 2 days. The results suggest that the placental permeability to steroids from the mother to the fetus declines toward the end of gestation in the rat.Acknowledgment. We are indebted to Professor Tatsuo Imori (Department of Veterinary Surgery, College of Agriculture, University of Osaka Prefecture) for his valuable suggestions during the course of this study.     

Effects of unmixed and mixed leaf litter of three species of plants on the development and growth ofPolydesmus angustus Latzel

Zusammenfassung Unter konstanten Temperatur-, Feuchtigkeits- und Lichtbedingungen entwickelt sich der MillipedierPolydesmus angustus rascher und wird grösser, wenn im Fallaub einzelner Baumarten gezüchtet, als in gemischtem Laub. Bei wechselnden Bedingungen (0–30 °C, wechselnder Feuchtigkeit und natürlichen Lichtverhältnissen) sind diese Unterschiede nur noch. für reine Eiche statistisch gesichert.

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This report is based on an investigation I carried out at the University of London, Royal Hollowey College.     

Chromosome studies and chromatographic analysis of free amino acids in two species of coleoptera

Résumé Le nombre des chromosomes diploïdes est de 20 dans les deux espèces de Coléoptères TénébrionïdesGonocephalum depressum etScleron sp. Il y a 18 autosomes et 2 chromosomes sexuels. Ils s'observent dans les acides amino libres. Dasns leScleron sp., il n'a en a que 14. La systématique de ces espèces est discutée sur la base de leurs caractères biochimiques.

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The author is grateful to Dr.A. R. Kasturi Bai, Central College, Bangalore (S. India), for her valuable suggestions and guidance. He is grateful to the Principal, Central College, Bangalore, for permitting him to work in the Zoology Department, Central College, and the Principal, Maharani's College, Bangalore, and the Director of Collegiate Education in Mysore, Bangalore, for the encouragement.     

Wound healing properties of naphthaquinone pigments fromAlkanna tinctoria

Summary From the roots ofAlkanna tinctoria Tausch, the alkannin esters of the following acids were isolated and identified: ,-dimethylacrylic acid, -acetoxy-isovaleric acid, isovaleric acid, and angelic acid. These esteric pigments showed excellent wound healing properties in a clinical study on 72 patients with ulcus cruris.I thank Dr A. Winkler, Heidberg Hospital and Prof. K. Kanitakis, Aristotle University, for the clinical studies. Prof. A. Sagredos, Aristotle University, for his help and Dr C. Gairola, Tobacco and Health Research Institute, for the mutagenicity tests. I also thank Dr G. A. Digenis and Dr L. Hurley, University of Kentucky, College of Pharmacy, for their critical reviews and comments.     

Constituents of propolis

Summary The major constituents of propolis collected in Western Australia have been isolated and identified as pterostilbene (5), xanthorrhoeol (6), sakuranetin (2) and pinostrobin (1).Acknowledgments. We gratefully acknowledge Dr H. Duewell of the University of Newcastle, New South Wales, for an authentic sample of xanthorrhoeol.     

Effect of Tween 80 on lipids ofMycobacterium phlei ATCC 354

Summary Addition of Tween 80 to the growth medium brings about qualitative and quantitative changes in the lipids ofMycobacterium phlei ATCC 354. The results suggest that Tween 80 itself may be a variant in the system.Acknowledgments. K. R. D. is grateful to the Indian Council of Agricultural Research, New Delhi, for the award of Senior Research Fellowship. This study was supported in part by funds from Indian Council of Medical Research, New Delhi, and University Grants Commision, New Delhi.     

Studies of the blood ofAscidia ceratodes. Total blood cell counts,differential blood cell counts,hematocrit values,seasonal variations,and fluorescent characteristics of blood cells

Summary Seasonal, and animal size and weight variations of the blood cells of the vanadium-containing ascidian,Ascidia ceratodes, were determined. The fluorescent properties of various cell types were ascertained, and discussed in terms of cell development, phylogenic position of the species, and chemicals in the cells.This investigation was supported by a grant from the Research Corporation and one of us (W.R.B.) received partial support from various University of California administrated fellowships. The current address of W.R.B. is Chevron Research Products, Richmond, CA. The use of the facilities at the Bodega Marine Laboratory, University of California are acknowledged.     

Temporal and spatial distribution of phosphoglucomutase (PGM) polymorphism in natural populations ofDrosophila melanogaster

Summary Drosophila melanogaster adults were collected for several years in various localities of Italy. The frequencies of thePgm electrophoretic alleles were determined and the similarity of the configuration of allelic frequencies observed. It was concluded that the PGM electrophoretic polymorphism could be maintained by random genetic drift in the natural populations studied only if the effective breeding size (N _e ) during the bottle-neck period is about 5000.I am grateful to Prof. D. Sperlich and Prof. W. Seyffert for their kind hospitality during my sojourn as Research Fellow of the Alexander von Humboldt Foundation in the Institute of Biology II at the University of Tübingen (FRG) where the final version of this paper has been done. The technical assistance of Mr A. Micheli is also acknowledged.     

The transmission of tumours induced in cockroaches by nerve severance

Résumé On a obtenu des tumeurs dans des blattes (Periplaneta americana) après la section du nerf récurrent. Des extraits ou des filtrats de ces tumeurs, exempts de cellules, ont provoqué des lésions semblables quand on les a injectés à des adultes ou des nymphes.

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Part of the work was carried out during the tenure of a Commonwealth Visiting Professorship at the University of East Anglia and Visiting Professorship in the Department of Anatomy, Albert Einstein College of Medicine, Bronx (New York, USA).     

Effect of exogenous iron on the viability of pathogenicNaegleria fowleri in serum

Summary WhenNaegleria fowleri (Lee) was incubated in newborn calf and human serum an amebicidal effect was observed. Heat inactivation of both sera resulted in the recovery of viable amebae after incubation in these sera. Exogenous iron added to non-heat inactivated calf serum improved viability slightly but was without effect when added to human serum not heat inactivated. Exogenous iron greatly enhanced growth and/or viability in heat inactivated calf serum. Viability of amebae also was considerably enhanced in human serum which was heat inactivated when pH was lowered in conjunction with iron supplements.Appreciation is expressed to Dr Ronald R. Weik (Dept. Biochemistry, Louisiana State Univ., New Orleans, LA. 70119) and Dr David T. John (Dept. Microbiology, Medical College of Virginia, Richmond, VA. 23298) for providing theNaegleria fowleri (Lee) used in this investigation.