Interphase studies with a simplified method of silver staining of nucleoli

Summary A simple silver staining method is presented providing a rapid and reliable technique for the selective staining of nuclear structures synthesizing ribosomal RNA (18S and 28S RNA).The critical advice of Prof. Dr W. Krone is gratefully acknowledged.     

Hybridization between Robertsonian karyotypic races of the common shrewSorex araneus

Summary British common shrews of the Aberdeen, Oxford and Hermitage Robertsonian karyotypic races were hybridized successfully in captivity. Hybrids, both simple Robertsonian heterozygotes and double Robertsonian heterozygotes with monobrachial homology, have been identified in an area of contact between the Oxford and Hermitage races. The relative fertility of these two types of hybrid is considered.I thank Dr. C. E. Ford F. R. S., Prof. F. W. Robertson and Dr A. E. Douglas for reading earlier drafts of this paper, Prof. F. W. Robertson, Dr J. R. K. Savage and Dr J. R. Clarke for laboratory facilities, Mrs J. E. Evans for technical assistance and S.E.R.C. for financial support.     

Development of visual sensitivity in the fly,Sarcophaga bullata

Summary Ontogeny of light response in the compound eyes of the fly,Sarcophaga bullata was investigated. Even though the eyes are structurally differentiated before eclosion they become electrophysiologically functional only after eclosion.Supported by grants from University of New Brunswick and NSERC to P.S. and NIH grant DHHS-1-RO1-EY 03408-03 to W.S.S. We would like to thank Mark Biagi and Roger Smith for technical assistance.     

The evolution of duplicate gene expression in the carp (Cyprinus carpio)

Summary The carp, Cyprinus carpio (Teleostomi), is a tetraploid species which currently expresses 52% of its duplicate enzyme loci. This level of duplicate gene expression in this cyprinid species is comparable to those observed in tetraploid Catostomidae, but higher than those in tetraploid Cobitidae.This research was supported by NSF grants GB 43995 and PCM 76-08383 to G.S.W. and by a Cell Biology Traineeship to S.D.F.We thank Suzanne Fisher and Dave Philipp for their helpful comments.     

A new antisickling agent: In vitro studies of its effect on S/S erthrocytes and on hemoglobin S

Summary 2-{benzoylamino} pyridinium benzoate (BAPB) has exhibited an antisickling effect with homozygous S/S erythrocytes in vitro. This study suggests that BAPB prevents sicklin by inhibiting the gelation of hemoglobin S.Acknowledgments. This research has been partly funded by a Sickle Cell Research grant from the State of Tennessee to Meharry Medical College. We gratefully appreciate the technical assistance of Mr Rudolf Harlan and Mrs Marjorie Deveau of the School of Graduate Studies. We offer our thanks to Dr J. W. Davis, J. D., Coordinator, Sickle Cell Project, Meharry Medical College for constant encouragement.     

Attraction ofScolytus scolytus (F.) to the components of Multilure,the aggregation pheromone ofS. multistriatus (Marsham) (Coleoptera: Scolytidae)

Summary The attraction ofS. scolytus to the components of Multilure is described. 4-Methyl-3-heptanol is an attractant which is synergised bya-cubebene. Multistriatin appears to be an inhibitor. A combination of 4-methyl-3-heptanol and cubeb oil is more effective as a bait forS. scolytus than Multilure.We thank Mr A. K. Hughes and Mr J. Boswell for their cooperation in allowing us to conduct experiments on Parham Estate; Mr D. Mobbs and Mr C. Thorne for the statistical analyses; Dr J. W. Peacock for samples of mixed isomers of multistriatin and distilled cubeb oil; Mrs J. Allsop and Mr N. J. Fielding for technical assistance. We are grateful to Mr D. Bevan, Dr J. H. Borden, Dr J. F. Grove and Prof. A. W. Johnson for their interest and encouragement.     

Demonstration of retinoic acid isomers in human urine under physiological conditions

Summary Untransformed retinoic acid has never been demonstrated in human excreta under normal physiological conditions. We have developed a two-step liquid chromatographic system for the demonstration of subnanogram amounts of this compound in human urine without administration of any precursor.The work was supported by a grant of the N.F.S.R. to W.L.     

Photoreceptor properties of an ectopic eye in the fleshfly,Sarcophaga bullata

Summary Ectopic eyes were produced on the fleshfly,Sarcophaga bullata by transplantation of imaginal eye discs. Electrophysiological and histological observations of these supernumerary eyes indicate the absence of synaptic connections between retinular cells and higher order neurons.Supported by an University of New Brunswick research grant to P.S. and NSF grant BNS-76-11921 and NIH grant 1-R01-EY-02487-01A1 to W.S.S.We would like to thank Dr I.A. Meinertzhagen for suggestions and Mary Johnson for technical assistance.     

Inhibition of an early stage of erythropoiesis in cultures of young chick blastodisc cells byRicinus communis agglutinin 120

Summary An early pre-erythroid phase of erythropoiesis in cultures of dispersed cell suspensions prepared from primitive streak and head-fold chick blastodiscs was very sensitive to inhibition byRicinus communis agglutinin 120.This work was supported by grants from the Medical Research Council and National Research Council of Canada. We thank Mrs S. Dorey and N.N. McGrath for technical assistance. S.D.W. is an Associate of the Medical Research Council.     

Regulation of grasshopper fecundity,longevity and egg viability by plant growth hormones

Summary Abscisic acid, a plant growth hormone, added in water to the grass diet of a grasshopper, greatly reduces the reproductive rate, as does gibberellin A₃ at doses 10 times greater. Reciprocal seasonal variations in quantities of these hormones could synchronize the growth and reproduction of insects with their host plants in the field.Acknowledgments. I thank Drs J. Pickett, G. Strobel, D. Meyers, I. Mills, L. Jackson and J. Bradbury for helpful consultations; Dr R. Lund and Ms W. Whitmore for statistical analyses, and S. Baril, M. Gaudet, D. Wrobetz, J. Cotter and W. Wallace for technical assistance. This research was supported by the Montana Agricultural Experiment Station, Project 420, and is published as Journal Paper No. 865.     

C-banding pattern on the chromosomes of the Japanese house shrew,Suncus murinus riukiuanus,and its implication

Summary The C-band on the chromosomes of the Japanese house shrew,Suncus murinus riukiuanus (Insectivora), was studied. Various types of C-banding pattern were found in the genome of this subspecies. Such banding patterns could be useful for an understanding of autosome and sex-chromosome polymorphisms withinS. murinus.Acknowledgment. The authors are very grateful to Prof. T. Wasano of Fukuoka University for his encouragement, Dr K. Ogawa of Fukuoka University, the Nohara family for help in collecting specimens, and Prof. E.W. Jameson, Jr, University of California, Dr J.W. Bickham and his students of Texas A & M University for comments.     

A demonstration of the resolution of NMR imaging in biological systems

Summary A proton NMR imaging study of several fruit specimens demonstrates the integrity and resolution of this new imaging method.Acknowledgment. We thank Professor E. R. Andrew, Dr W. S. Moore and Miss C. Simaroj for their contributions. The work was supported by MRC grant G975-102.     

Naphthoquinones in defensive secretion of an opilionid

Summary The defensive secretion of the opilionidPhalangium opilio contains 1,4-naphthoquinone and 6-methyl-1,4-naphthoquinone. Naphthoquinones are of rate occurrence in arthropods, having previously been reported only from certain tenebrionid beetles.Paper No. 60 of the series: Defense Mechanisms of Arthropods.Acknowledgments. Partial support by the National Institutes of Health (grant Nos. AI-12020 and AI-02908, and fellowship award CA 05646 to D.F.W.) and the National Science Foundation (grant No. BMS 74-15084) is gratefully acknowledged. We thank Dr W.A. Shear for identifying the opilionid, and S. Daniels, K. Dodge, M. Guzewich and C. Smith for helping collect the specimens..     

Electrophysiological evidence for chemosensitivity to adenosine,adenine and sugars in spodoptera exempta and related species

Summary Electrophysiological studies show that Spodoptera exempta and closely related species possess a receptor with specific sensitivity towards adenosine and adenine. 2 other types of receptors responded to certain sugars. The functional significance of these receptors in controlling chemoresponses of the larvae is discussed.This work was initiated during a stay at the International Centre of Insect Physiology and Ecology, Nairobi, Kenya. I am indebted to Professor J. W. S. Pringle, FRS, for valuable discussions.     

Hageman factor activation and tight junction disruption in mice challenged with attenuated endotoxin

Summary Endotoxin treated with chromium chloride is less toxic to mice than the parent molecule, but can disrupt intestinal permeability barriers and has an enhanced ability to activate Hageman factor.We wish to thank Drs M.W. Brightman and T.S. Reese from the Department of Neurocytology, National Institutes of Health for the use of their Balzers freeze-fracture instrument.     

Fever and survival in the rat. The effect of enhancing the cold defence response

Summary Continuous cooling of the spinal cord for 6 and 28 days had a probably beneficial effect on the outcome of salmonellosis in the rat, suggesting that the apparently harmful effect of high fevers is not due to the cold defence response but may rather be caused by the high body temperature.I thank Dr W. Mannheim from the Institute of Hygiene for kindly furnishing the cultures ofS. enteritidis. This work was supported by the Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 122 and Schwerpunktprogramm Temperature-regulation und-adaptation).     

Exocytosis of secretory granules — a probable mechanism for the release of neuromodulators in invertebrate neuropiles

Summary Presynaptic terminals typically contain secretory granules, usually 100–200 nm in diameter, in addition to the smaller synaptic vesicles. Evidence is presented that granule exocytosis is a widespread phenomenon in invertebrate neuropiles. Such secretory release is apparently associated with morphologically unspecialized regions of the plasmalemma, rather than synaptic thickenings.Acknowledgments. The authors gratefully acknowledge the assistance of Mr R. M. Hewit and Mrs. S. Al-Yousuf. Supported by research grant GR/A88743 from the S.E.R.C., U.K., to D.W. Golding.     

Effect of cycloheximide on germination-induced isocitritase development and decline in intact and excised flax cotyledons

Summary Removal of embryo axis before germination markedly prevents the development as well as subsequent decline in Flax cotyledon isocitritase. Cycloheximide inhibited the development and decline of the enzyme in intact cotyledons but prevented only the former in excised cotyledons.We thank Prof.W. Rahman, Head, Department of Chemistry for his interest and C.S.I.R. (India) for the award of Junior Research Fellowship to F.R.K.     

Catalase and dehydroascorbate reductase in human polymorphonuclear leukocytes (PMN): Possible functional relationship

Summary In leukocytes (PMN) of individuals with Swiss type acatalasemia, the rate of dehydroascorbate reduction is 4 times normal. This observation suggests that the protective function served by catalase in human PMN is supported by dehydroascorbate reductase.This work was aided by grants to L.S. and R.B. from the American Cancer Society (CH-30B), the Grand Bethel of Oregon, International Order of Job's Daughters, and to S.W. and H.A. by grant number 3.384.74 from the Swiss National Science Foundation.     

The siderophore mediated release of iron and magnesium from Mt St. Helens' ash and silicate rock standards

Summary Substantial amounts of iron and magnesium were observed to be released from ash from Mt St. Helens' and US Geological Survey Silicate Rock Standards by the siderophore rhodotorulic acid.This project was supported by the Robert A. Welch Foundation (Y-773) and the Lamar Research Council. We are grateful to S. Arnow, W. Matthews III, V. Pullen and M. Akers for their interest and assistance in obtaining Mt St. Helens' ash samples.