Statice Virus Y - a Virus related to Bean Yellow Mosaic and Clover Yellow Vein Viruses

The authors are greatly indebted to the Deutsche Forschungsgemeinschaft for financial support, to Miss B. M urthlm , Mrs. U. H erzberg , Mrs. B. H ane and Miss P. R ahse for reliable technical assistance and to Dr. M. H ollings , Dr. R. O. H ampton and Mr. D. Z. M aat for gifts of antisera.     

Keratin-like fibres in the hemichordate Rhabdopleura compacta

Summary The coenecium of Rhabdopleura is a tube that surrounds the zooid. It is secreted by the cephalic shield of the zooid and contains three sorts of fibres in an electron lucent matrix. One of the fibre types contains a double helix of fine fibrils. Preliminary histochemical investigations suggest that the fibres may be keratinous.I wish to thank Professor J. Z. Young F.R.S. for enthusiastic advice and encouragement. Dr. R. Bellairs generously provided the facilities for electron microscopy. Dr. A. J. Southward and Dr. A. Stebbing of the Plymouth Marine Biological Laboratory generously gave of their time and expertise, and helped me to obtain and identify the specimens. Dr. R. Willis and Miss Marion Dennison assisted with the preliminary stereoscopic electron microscopy. Mr. R. Moss gave excellent technical and photographic assistance.     

Autoactive molluscan neuron: Reflex function and synaptic modulation during feeding in the terrestrial slug,Limax maximus

Summary The salivary burster (SB) is an autoactive motoneuron to the salivary duct of the terrestrial slugLimax maximus. The SB is electrically coupled to protractor motoneurons and inhibited by the metacerebral giant cell. During feeding these synaptic inputs cause SB activity to be phase-locked to the protraction-retraction cycle. The SB can be used as a clear and reliable monitor of feeding motorprogram activation.We thank Dr. Joseph Jin Chang for invaluable assistance with some of this work. Support was provided by NSF grant BMS74-15217 to D.J.P., NSF grant BMS74-03572 to A.G., and a grant from the Spencer Foundation.     

中枢神经元树突电活动和树突返传动作电位在突触可塑性调控中的作用——悼念树突功能研究的先驱张香桐院士

本文回顾了张香桐院士在上世纪50年代完成的有关神经元树突电活动和功能特性的先驱性研究工作,简要介绍了此后成为神经科学研究热点之一的树突在中枢突触传递和突触可塑性形成中所起作用的研究概况,籍以说明张香桐院士不愧为神经科学研究历史上做出过突出贡献的人物之一。     

The effects of prostaglandin F2α on the fine structure of the corpus luteum of the pregnant hamster

Summary The commonest intracellular organelle characteristic of the Phylum Cnidaria or Coelenterata (Subclass Zoantharia) is the spirocyst. Based on scanning and transmission electron microscopy of the tentacles of sea anemones and corals, it appears that the tip of the spirocyst is either exposed to the environment or covered by a thin plasma membrane and often has a pebbled or knobby appearance. Surrounding the spirocyst tip is a ring-like structure which seems to be formed by the junction of the enclosing cell (the spirocyte) and the tip of the spirocyst. The spirocyst thread is continuous with the capsule wall and emerges from within the apical ring during discharge. No ciliary structures appear to be associated with spirocysts. Instead, two different types of microvilli have been found: short microvilli on the spirocyte itself and long microvilli furnished by the cell or cells surrounding the spirocyte. The significance of these findings is discussed in relation to the reception of stimuli for spirocyst discharge.Thanks are due Dr. Cadet Hand for the use of facilities of the Bodega Marine Laboratory of the University of California and Dr. R.K. Thompson, P. Nemanic, H. Sampson, F. Doroshow, E. Chang and B. Miller for expert technical assistance. The use of the facilities of the Electron Microscope Laboratory and the Electronics Research Laboratory of the University of California and the Electron Microscope Laboratory of the Florida State University is gratefully acknowledged. Part of this work was made possible by NSF Grant # GB-40547 to the senior author.     

Crevice organs: Sensory structures on the wings of dragonflies (Insecta,Odonata)

Summary Crevice organs are small, elongate, innervated indentations in the hard cuticle of one wing vein of aeshnid dragonflies. There are four groups on each wing. The structure and orientation of crevice organs suggest that they detect strains in the cuticle during wing movements.I wish to thank Mr. R. Whitty and staff for technical assistance with the scanning electron microscope and Dr. E.E. Ball for helpful discussion     

Isotocinergic neurons in the goldfish hypothalamus: Physiological and morphological studies on chemically identified cells

Summary Isotocinergic (IT) neurons show physiological and morphological characteristics that are similar to those of other preoptic neuroendocrine cells in the goldfish. Preoptic IT cells show resting membrane potentials of 20–55 mV, action potentials of up to 100mV, and physiological evidence of axonal branching. Dye-marked IT cells measure 14–56 m, their dendrites projecting to the ependyma and into the hypothalamic neuropil, their multiple beaded axons projecting to the pituitary. Indirect immunofluorescence identifies these dyemarked cells as IT. By combining electrophysiological, dye-marking and immunocytochemical techniques we can now, for the first time, study single, antidromically-identified peptidergic neurons of a specific type in vertebrate and invertebrate species.Supported by Grants from the USPHS (NS-13411 and NS-05696)The authors wish to thank Ms. S. Curtis for editorial assistance, Ms. D. Cronce for skillful technical assistance, Dr. W.W. Stewart for helpful suggestions and for his generous gift of Lucifer Yellow-CH, Dr. M. Manning for his generous gift of high quality peptides, and Dr. R.R. Dries and J.D. Fernstrom for kindly supplying antisera     

Lateral connections between heart muscle cells as revealed by conventional and high voltage transmission electron microscopy

Summary The lateral surfaces of heart muscle cells are interconnected by a varied and extensive network of structures that exist in addition to intercalated discs. Ultrastructural images of this network are vastly improved over those from epoxy-embedded material, particularly for low density components, through the application of a method for removing the embedding matrix from thin or thick sections that are then stereoscopically analyzed with standard or high voltage transmission electron microscopy. The connections include cables, 3–20 nm in diameter, multi-strand cables, 10–40 nm-granules, meshlike mats, and sheets, all extensively interwoven. It is suggested that intercellular connections of varying strength and distribution aid in the integration of mechanical performance of the large population of myocytes during the contractile cycle of the heart.This study was supported by a grant from NIH Biotechnology Resources through the University of Colorado High Voltage E.M. Laboratory, NIH Research Grant HL 24336, a N.Y. Heart Association Grant-in-Aid, and NIH Research Career Development Award HL 00568I thank Dr. E.H. Sonnenblick for continual aid and encouragement and Dr. R. Terry, Ms. Y. Kress, and Ms. J. Fant for use of facilities. I also thank Dr. K.R. Porter for guidance in the use of the HVEM technique, Dr. J.J. Wolosewick and Dr. M. Fotino for valuable suggestions, and Ms. J. Fleming, Mr. G. Wray, and Mr. G. Charlie of HVEM staff at Boulder. I acknowledge Dr. F. Pepe for use of facilities, Dr. R. Bloodgood for comments, and Mrs. L. Cohen-Gould, Ms. T. Downey, Mr. F. Reingold, Mrs. T. Maio, and Mrs. R. Shamoon for excellent assistance     

Hygro- and thermoreceptive triad in antennal sensillum of the stick insect,Carausius morosus

Summary The receptor cells in a poreless sensillum on the antenna ofCarausius morosus were examined electrophysiologically. Two of the units are antagonistic regarding humidity, one responding with an increase in impulse frequency to rising humidity (moistair unit) and the other to falling humidity (dry-air unit). Another reacts to falling temperature with a rise in impulse frequency (cold unit). In some cases responses from a fourth unit were also present. Its modality is uncertain. A method of marking the sensillum with a cactus needle for subsequent structural examination after recording is described.Supported by the Alexander von Humboldt Foundation and by the Fonds zur Förderung der wissenschaftlichen Forschung in ÖsterreichI wish to express my gratitude to Prof. Dr. F. Schaller and to Prof. Dr. H. Altner for their support of this study, to Dr. R. Loftus for very valuable discussion, and to Ms. C. Danner for her technical assistance.     

Movement of neurosecretory product through the anatomical compartments of the neural lobe of the pituitary gland

Summary Electron microscopic studies of the carotid body of the domestic fowl (Gallus gallus domesticus) have shown Type I and Type II cells combined with axons into compact groups. The many Type I cells in the depths of the organ had a body, containing the nucleus, and an elongated, flared process. Some of the Type I cells in the superficial regions tended to be spindle-shaped. Type I cells were characterised by membrane-bound, dense-cored vesicles about 120 nm in diameter. Type II cells invested the Type I cells and had axons embedded in them as in Schwann cells.The fine structure of the carotid body in the domestic fowl resembles that of the Lovebird (Uroloncha domestica) and of various amphibia and mammals. The possibility is discussed that the Type I cells may have a chemoreceptor or a general secretory function, or even both pathway for functions together. The main role of the Type II cells seems to be to provide a of these axons leading to or from Type I cells.The authors are grateful to Mr. R. P. Gould of the Department of Anatomy, Middlesex Hospital Medical School for permission to use some of his and Dr. Hodges' original material in the illustrations. Dr. Hodges also wishes to thank the A.R.C. and the University of London Central Research Fund for financial assistance. We are also most appreciative of the photographic assistance of J. Geary.     

A study of pattern and process in coastal vegetation using principal components analysis

A study is made of the dune system at Tentsmuir Point National Nature Reserve, Scotland, using transects crossing the vegetation zonation. Principal Components Analysis and tabular ordination are used to analyse the data, and an attempt is made to relate the results obtained to the dynamics of the system. The effects of different management regimes are considered, and it is concluded that the establishment of pine on the area has the largest effect on the development of the vegetation. Reduction in grazing pressure by rabbits is found to increase species diversity slightly, but has no major influence as yet on vegetation development. While some information on the dynamics of the vegetation can be inferred, the problems involved in this are considered to be large, and the study raises a number of questions to be studied in greater detail. It is concluded that permanent plots would be the most effective method to employ.Nomenclature follows Clapham, Tutin & Warburg (1962) for vascular plants, Watson (1968) for bryophytes, and Duncan (1970) for lichens.We should like to thank Dr. R. A. H. Smith of the Nature Conservancy Council for her assistance and permission to work on Tentsmuir Point N. N. R., and Mr. J. G. Young, then warden at Tentsmuir for his help at the start of the project. We are grateful to Dr. R. Meutzelfeldt for computational advice. In addition, one of us (R.J.H.) would like to thank Dr. E. van der Maarel and Dr. R. S. Clymo for their tuition during the Nordic Council for Ecology course Numerical Methods in Vegetation Analysis' in Lund, September, 1979.     

命名建议——以Diabolepis代替Diabolichthys Chang et Yu,1984

<正> 因肺鱼 Diabolichthys Chang et Yu,1984 是鳐类 Diabolichthys Holmes,1856 (p.45) 的晚出同名,应予废弃,建议代之以 Diabolepis.     

Differentiation of ovarian and testicular interstitial cells during embryonic and post-embryonic development in mice

Summary Different steps in mouse ovarian and testicular development have been studied in order to compare the time sequences during the in vivo differentiation of steroidogenic cell populations growing in contact with male and female gonocytes. These time sequences indicated a basic common developmental pattern: early signs of steroid synthesis in the male gonad, but late entering into meiotic prophase of XY germ cells; early meiosis but late steroidogenic activity in the ovary. In both male and female interstitial tissues, signs of involution were found following a period of exponential development.Dedicated to Prof. Dr. med. H. Leonhardt on the occasion of his 60th birthdaySupported by the Deutsche Forschungsgemeinschaft (Pe 104/8)We wish to thank Dr. B. Nabarra, M.-F. Rousseau-Merck and D. Sandoz for helpful advices throughout this study, as well as Mrs. L. Andrianarison and Mrs. R. Sprang for skilful assistance     

Arrays of particles in the sarcolemma of the distal accessory flexor muscle of the lobster

Summary Freeze-fracture of the distal accessory flexor muscle reveals the presence of randomly distributed arrays of P- and E-face particles. The particles are arranged in regularly spaced rows which parallel one another and, in general, the long axis of the muscle fiber. P- and E-face arrays differ in their structure and are apparently complementary. A model explaining the apparent interrelationship of the P- and E-face arrays is presented. The functional significance of the arrays is not known.We thank J. Pearce for technical assistance and Dr. R.R. Shivers, Department of Zoology, University of Western Ontario for his provision of freeze-fracture facilities. This work was supported by grants from the Natural Sciences and Engineering Council of Canada and the Muscular Dystrophy Association of Canada to C.K.G.     

Zoosporic marine fungi from the Pacific Northwest (U.S.A.)

Summary An investigation of the zoosporic fungi in the vicinity of the Friday Harbor Laboratory, San Juan Is., Washington, revealed the presence of great numbers of fungi. With one exception (Olpidium sp.) these were all biflagellate organisms. Predominating were species (11) of Thraustochytriaceae which abounded in water, in association with seaweeds, intertidal sands, and particularly on the surface of bottom samples down to depths of 298 m. A twelfth species of this group has several peculiarities and needs further investigation. Of the algal parasites, one on Polysiphonia and Pterosiphonia is considered new and termed Eurychasma joycei n. sp.The assistance of Drs. R. E. Norris and G. J. Hollenberg in calling my attention to certain algal parasites is gratefully acknowledged. I am also indebted to my colleague Dr. H. C. Whisler, and to Dr. C. Anastasiou for assistance in photographic work.     

Indian chytrids. III. Species of rhizophlyctis isolated on human fibrin film

Summary Human fibrin film has been used as an additional substratum to trap zoosporic fungi in watered soil samples. This semi-transparent film is prepared from human plasma proteins by fractionation and is used as a substitute in dural surgery.Three new species ofRhizophlyctis, R. lovetti, R. fuscis, andR. hirsutus, as well asPhlyctorhiza variabilis and numerous other water molds have been trapped on this substratum in watered soil samples from India.This study has been supported by the U. S. Program in Biology, International Indian Ocean Expedition, and conducted at the Central Marine Fisheries Research Institute, Mandapam Camp, Madras State. I am very grateful to Dr.S. Jones, Director of the Institute, for research facilities and assistance.     

Notes on the Genus Osmanthus Lour. in China

In the present paper a new species, Osmanthus gracilinervis Chia ex R. L. Lu, is described from Guangxi. The new species is also distributed in Guangdong, Jiangxi, Zhejiang, Hunan and Sichuan. Based on the analysis of a great deal of specimens, eight species, i.e. Osmanthus corymbosus H. W. Li, O. longispermus H. T. Chang, O. angustifolius H. T. Chang, O. triandrus H. T. Chang, O. longicarpus H. T. Chang, O. omeiensis Fang ex H. T. Chang, O. nanchuanensis H. T. Chang and 0. cylindricus H. T. Chang, are reduced as the synonyms of O. marginatus (Champ. ex Benth.) Hemsl. var. marginatus. O. longissimus H. T. Chang and O. pachyphyllus H. T. Chang are respectively reduced to varieties of O. marginatus, i.e.O. marginatus var. longissimus (H.T. Chang) R. L. Lu and var. pachyphyllus (H. T.Chang) R. L. Lu. And finally O. maximus H. T. Chang is treated in this paper as a synonym of O. matsumuranus Hayata.     

Directionally selective motion detecting units in the optic lobe of the honeybee

Summary We have found four classes of neurons in the honeybee optic lobe. These neurons respond to changes in light intensity and selectively to movement of objects within the entire acceptance angle of a compound eye. We suggest that these neurons are part of the neural system that controls flight, for example the optomotor response. Properties of these units are described in this paper. To our knowledge this is the first report of recording from interneurons of the honeybee.We thank Mrs. B. Hsei and Mrs. D. Hodgetts for technical assistance. Bees to establish the wild-type colony were given by Dr. P. Wells, Occidental College; bees to establish the white-eyed mutant colony were given by Dr. H. Laidlaw, University of California at Davis, California.This research was supported by National Institutes of Health, U.S.P.H.S. Grant NB03627 to Dr. G. D. McCann (CIT), and A.F.O.S.R. Grant 70-1869 to LGB.One of us (WK) is indebted to the Commitee on International Exchange of Persons, Washington D.C., for making available a Fulbright Travel Grant. WK also thanks Dr. G. D. McCann for the invitation to the California Institute of Technology.     

Morphological differences in the interactions between human mononuclear cells and coated or uncoated sheep red blood cells

Summary Enriched preparations of E, EA and EAC rosettes formed by human peripheral blood mononuclear cells were freeze-etched and examined electron-microscopically. In E rosettes only lymphocytes were involved, whereas in EA and EAC rosettes lymphocytes and mononuclear phagocytes participated as rosette-forming cells. In EA and EAC rosettes, cytoplasmic extensions of the rosette forming cell were seen to penetrate the sheep red blood cell, whereas E rosettes showed a broad zone of adherence without penetration. None of the three types of rosettes showed an interspace between the membranes. Unlike E rosettes, EA and EAC rosettes showed polarity in the adherence of sheep red blood cells. These observations made by freeze-etch electron microscopy indicate distinct morphological differences between rosettes formed with coated or uncoated erythrocytes.The authors wish to thank Prof. Dr. A. Cats, Dr. P.C.J. van Breda Vriesman and Dr. J.C.H. de Man for helpful discussion and criticism; the assistance of Miss R. Kleinjan and Mrs. A.C. Scheurkogel-van Efferen is gratefully acknowledged. This work was supported in part by a grant of the Praeventiefonds