Die Augenstielbewegungen der Languste (Palinurus vulgaris)

Summary Palinurus vulgaris shows clear compensatory eye stalk movements when turning actively around a vertical axis. Exactly the same eye stalk movements are observed after blinding of the animal (measurement of film pictures). On passive rotation only the intact animal shows compensatory eye stalk movements (= optomotoric reactions); in the blinded lobster such movements are lacking, except when a torsion of the body with respect to the legs is effectuated (stimulation of proprioceptors). It is suggested that the compensatory eye stalk movements of the actively turningPalinurus are no optomotoric reactions, and possibly no sensory reactions at all; but that they are spontaneous acts originating primarily within the central nervous system.     

Elektrische antworten der statonerven der schnecken (Arion empiricorum undHelix pomatia) auf Drehreizung

Summary Single units of the statocysts of 2 gastropod molluscs were found responding to rotation only in a special range. Since adaptation was observed for each maintained position these units are thought to be of the phasic-tonic type. Efferent impulses have also been recorded from the statocyst nerves.     

Lauterzeugung und Schallwahrnehmung bei der Languste (Palinurus vulgaris)

Summary The sounds produced by the Spiny Lobster,Palinurus vulgaris, and their origin are briefly described. One animal reacted clearly to similar artificial sound stimuli, in some cases even vocally. Elimination of both statocysts had no influence on these reactions.     

The oak processionary caterpillar (Thaumetopoea processionea L.) an urticating caterpillar related to the pine processionary caterpillar (Thaumetopoea pityocampa Schiff.) (Lepidoptera,Thaumetopoeidae)

Summary The hairs ofThaumetopoea processionea caterpillars (Lepidoptera) provoke a cutaneous reaction in man and animals. The urticating apparatus, the urticating gland which produces hairs, and the urticating hairs, are similar to those of theT. pityocampa caterpillar. The irritant fraction extracted from hairs contains soluble proteins; one of these shows immunological identity with thaumetopoein, the urticating protein of theTh. pityocampa caterpillar. This thaumetopoein-like protein is currently undergoing isolation and will be subjected to dermatological tests.     

Hymenaea protera sp.n. (Leguminosae,Caesalpinioideae) from Dominican amber has African affinities

Hymenaea protera is described from amber originating from La Toca mine in the Dominican Republic. The fossil species is characterized by the presence of reduced petals as well as distinctly clawed showy petals with cordate to reniform bases and a glabrous, verrucose ovary with long hirsute hairs at its base and along one margin. The fossil species most closely resembles the extantH. verrucosa Gaertner which occurs in East Africa and adjacent islands. These findings are interpreted as supporting a hypothesis that the genusHymenaea arose in the late Cretaceous on the combined South American-African continents and that Cretaceous and early Tertiary landmass movements were significant in determining the present amphi-Atlantic distribution of the genus. It is proposed that at least the majority, if not all, of the amber recovered from La Toca mine and other mines in the vicinity with similar-aged deposits originated fromH. protera.     

Der Trockenheitssinn bei Larven vonDrosophila Melanogaster

Summary Larvae ofDrosophila melanogaster perceive very small differences of relative humidity if the humidity is high, whereas the perceptible differences are relatively large in dry air. The sense organs for these perceptions are the so-called tufted organs on the ventral side of the thoracic segments. From the fact that the threshold of sensation is high in dry air, we conclude that the absence of humidity irritates the sense organs. We think, therefore, that they are aridity receptors.     

Effects of TA [4-ethoxy-1-(p-tolyl)-s-triazine-2,6-(1H, 3H)-dione] on growth,antheridium differentiation and gibberellin uptake of gametophytes ofAnemia phyllitidis L. Sw.

Summary Synergistic effects of TA on gibberellin-dependent reactions in spermatophytes are not detectable in gametophytes of the fernAnemia phyllitidis where gibberellin substitutes for antheridiogens with regard to induction of male sexual organs and dark germination. In this archegoniate TA caused a significant reduction in growth rate and morphogenesis of the gametophytes, inhibitions that were not abolished by simultaneous application of gibberellin.     

Axoneme patterns of spermatozoa of Asian horseshoe crabs

Summary Ultrastructural studies of flagella of spermatozoa of horseshoe crabs revealed that three Asian species (Tachypleus tridentatus, T. gigas andCarcinoscorpius rotundicauda) had a 9+0 axoneme pattern that was different from the usual 9+2 pattern ofLimulus polyphemus. This difference is consistent with the phylogeny of horseshoe crabs.Contribution No. 40 from the Shimoda Marine Research Center. Supported in part by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan.     

Dual role of cAMP duringDictyostelium development

cAMP plays an essential role duringDictyostelium development both outside and inside the cell. Membrane-bound receptors and adenylyl cyclase are responsible for sensing and producing extracellular cAMP, whereas a phosphodiesterase is responsible for maintaining a low basal level. The molecular events underlying this type of hormone like signalling, which are now beginning to be deciphered, will be presented, in the light of cAMP analogue studies. The importance of intracellular cAMP for cell differentiation has been demonstrated by the central role of the cAMP dependent protein kinase. Mutants as well as strains obtained by reverse genetics will be reviewed which lead to our current understanding of the role of intracellular cAMP in the differentiation of both stalk and spore cells.     

Etude de l'influence d'une microsporidiose sur les électrophorégrammes (protéinogramme et zymogramme) des protéines de l'hémolymphe deCarcinus mediterraneus (Crustacé, Brachyoure)

Summary The use of the method of concentration gradient of polyacrylamide gel, electrophoresis has permitted to reveal a difference in zymograms when studying the hemolymph of healthy crabs and that of crabs parasitized by the muscular microsporidaThelohania, maenadis., The zymograms of the parasitized crabs present an increase in chymotrypsin activity and variations in the zones of esterase activity.

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Contribution n^o 1 du Centre de Parasitologie et de Pathologie comparées de l'Université des Sciences et Techniques du Languedoc, F-34060 Montpellier Cédex.     

Interaction and interrelation of P2X7 and P2X4 receptor complexes in mouse lung epithelial cells

P2X4 and P2X7 receptors are ATP-gated ion channels that are co-expressed in alveolar epithelial type I cells. Both receptors are localized to the plasma membrane and partly associated with lipid rafts. Here we report on our study in an alveolar epithelial cell line of the molecular organization of P2X7R and P2X4R receptors and the effect of their knockdown. Native gel electrophoresis reveals three P2X7R complexes of ~430, ~580 and ~760 kDa. The latter two correspond exactly in size to signals of Cav-1, the structural protein of caveolae. Interestingly knockdown of P2rx7 affects protein levels, the intracellular distribution and the supramolecular organization of Cav-1 as well as of P2X4R, which is mainly detected in a complex of ~430 kDa. Our data suggest upregulation of P2X4R as a compensatory mechanism of P2X7R depletion.     

Die physikalische Kieme der Wasserinsekten

Summary The air stores carried by a number of aquatic insects have: a) a hydrostatic function (Brocher, Oortwijn-Botjes, Thorpe, andCrisp); b) the function of an oxygen store (Ege, de Ruiter et al.) and c) the function of a physical gill (Strauss-Durckheim, Ege, etc.). The fact that oxygen is taken up from water with the aid of an air bubble was demonstrated forNotonecta by comparing the life time of insects with and without physical gill (while replenishing the oxygen store from the air was prevented) byEge, and forCorixa byPopham, whileVlasblom determined the oxygen uptake from water with and without air bubble forNotonecta, Naucoris, Corixa, Sigara andNepa. Nepa andSigara can take up considerable quantities of oxygen by cutaneous respiration.During the summer, the gill function of the air store ofNotonecta andNaucoris is of importance only when a water current passes along the animal, caused by ventilation movements of the legs (de Ruiter et al.). At low temperatures, however, the metabolic rate is so low that in many instances the physical gill provides the oxygen required without ventilation movements.An apparatus for the simultaneous determination of oxygen uptake from air and water (Wolvekamp andVlasblom) gave results that provided a means of evaluating the importance of the physical gill function.In some cases, the air store, although in direct contact with the water, does not need to be replenished. InAphelocheirus andElmis, the negative pressure in the bubble, caused by oxygen consumption and the diffusing out of part of the nitrogen, is compensated for by the mechanical resistance of a feltwork of thin hairs and the surface tension of the boundary layer of the water (Thorpe andCrisp). In the African beetle,Potamodytes, the unprotected air bubble is permanent because the strong river currents produce a lowered pressure around the animal according toBernoulli's principle (Stride).     

Comparison of the effects of illumination on the melanophores of intact and eyestalkless fiddler crabs,Uca pugilator,and inhibition of the primary response by cytochalasin B

Summary Approximately 100 times more illumination is required to produce pigment dispersion in the melanophores of eyestalkless fiddler crabs (Uca pugilator) than in the melanophores of intact crabs. The pigment in melanophores of isolated legs will normally disperse in response to irradiation, but this response is inhibited by cytochalasin B.This investigation was supported by a Faculty Research Grant from Western Kentucky University toT. P. Coohill and by Grant No. GB-27497 toM. Fingerman from the National Science Foundation.     

Les manifestations électriques consensuelles de l'activité rétinienne chez l'homme (Electrorétinographie binoculaire)

Summary Binocular Electroretinography in man shows that the elective light-stimulation of one retina produces a normal Electroretinogramm at the stimulated, ipsilateral eye, furthermore a bioelectric consensual response at the contralateral eye. This latter response consists in a positive deflection, corresponding to increased electropositivity under the corneal electrode. A close synchronism exists between the consensual response and the secondary rise (c-potential) of the ipsilateral Electroretinogramm. The consensual response does not appear to be of pupillary or oculomotor origin, but can probably be identified with thec-potential, the significance of which will have to bee reexamined, as well as the problem of the efferent innervation of the retina.     

The significance of the Barrovian Case

The Barrovian Case is a technical problem, hitherto unsolved, involving either a double convex lens or a concave mirror. The problem, due to Isaac Barrow and reported by Berkeley in his New theory of vision, is that what is seen in certain instances with these devices seems to violate historically important principles of optics. One is the ‘ancient principle’ of Euclid that the object should be seen at the intersection of the refracted (or reflected) ray with the perpendicular of incidence; the other is the principle attributed to Kepler that the perceived distance of an object varies indirectly with the divergence of the rays it sends to the eye. The most obvious difficulty is that the object should appear, impossibly, behind the eye. As it happens, despite some strong claims that have been made about the significance of the problem, the principles generating it no longer have the centrality in optics they were once thought to have. But even accepting them, the problem can be solved by viewing it as an instance, albeit a very complicated one, of the classical problem of the relativity of sense perception.     

Increase in the total reducing substances in the hemolymph of the freshwater crab,Barytelphusa guerini,produced by a pesticide (DDT) and an indolealkylamine (serotonin)

Summary DDT and serotonin produced significant increases in the total reducing substances in the hemolymph of intact crabs,Barytelphusa guerini, apparently by triggering release of the hyperglycemic hormone.     

Sérotonine et scglycémie chez les crustacés

Summary Injection of 0.2 cm³ of 5-HT 0.1% inCarcinus maenas has a powerful hyperglycaemic effect and determines at the same time a dispersion of the melanin granules in chromatophores of eyestalkless crabs. In both instances, 5-HT mimics the effects of the injection of an extract from the eyestalks.     

Über die Reizung des Ferntastsinns bei Fischen und Amphibien

Summary Fishes and aquatic amphibians are able to detect and locate moving bodies and even obstacles at some distance by means of their lateral-line sense organs (Ferntastsinn). As was shown experimentally, the main physical process involved in these reactions are certain local damming phenomena in front of the moving object (rise of pressure, displacement of water particles). Obstacles cause an alteration of the damming phenomena produced by the moving animal's body itself (increase of water resistance).Kramer's different view is rejected; he overlooked the existence of damming phenomena and was not aware of the fact thatXenopus laevis reacts to surface waves even when the animal is totally submerged.     

Enzymatic processing of pheromones and pheromone analogs

Summary Pheromone perception requires rapid enzymatic degradation of the active chemical signal in the sensory hairs. Three insects are used to illustrate chemical approaches to studying the degradation of pheromones by antennal enzymes. First, hydrolysis of acetate and haloacetate esters is examined in the diamondback moth,Plutella xylostella. Second, aldehyde oxidation and the selective inhibition of the oxidase and dehydrogenase activities are described for the tobacco budworm moth,Heliothis virescens. Finally, a stereochemical analysis of the epoxide-hydrase catalyzed addition of a water molecule to the oxirane ring of disparlure is described for the gypsy moth,Lymantria dispar.     

Release of Ca2+ from intracellular pools stops cytoplasmic streaming inTradescantia staminal hairs

Summary Ionophore A 23187 reversibly stops cytoplasmic streaming inTradescantia staminal hairs. Cessation of streaming occurs even in the absence of free Ca²⁺ ions in the medium.