Étude histologique du système neuro-endocrinien de l'abeille

Résumé L'auteur a utilisé différentes techniques de la coloration et la microscopie sur fond noir pour l'étude histologique du complexe neuro-endocrinien de l'abeille.On distingue deux types de cellules dans la pars intercerebralis. L'examen ultrastructural révèle qu'un troisième type de cellule est identique au second type, mais la technique appliquée au cours de ces travaux différencie encore un autre type de cellule (publication en cours de préparation).Le trajet des axones partant de la pars intercerebralis réclame une attention particulière, la présence de trachéoles à forte réaction phloxinophile pouvant y faire croire à la présence d'une sécrétion phloxinophile.La même technique de coloration appliquée après fixation en solution de Carnoy ne donne aucune différenciation de la sécrétion hématoxyline-positive en une fraction soluble et en une fraction insoluble dans l'alcool.La coloration à la paraldéhyde-fuchsine selonEwen (1962) confirme les résultats de la coloration selonGomori.La coloration à la paraldéhyde-fuchsine selonHalmi (1952) ne permet pas de déceler un produit de sécrétion dans les cellules des corpora allata de l'abeille (ouvrière).Les éléments névrogliques du système neuro-endocrinien de l'abeille domestique sont nettement différenciés par la coloration à la fuchsine acide Light Green selonAlzheimer.L'éclairage sur fond noir révèle que les cellules de la pars intercerebralis de l'abeille ont à un degré élevé la propriété de diffuser la lumière. Certaines autres parties du complexe cérébral présentent cependant le même phénomène, de sorte que cette technique est sans utilité pratique pour la différenciation des cellules neuro-sécrétoires.

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Summary The neuro-endocrine complex of the honey bee was histologically examined by means of various staining techniques and dark-field microscopy.Two types of cell were differentiated in the pars intercerebralis. A third type appeared to be identical with the second after ultra-structure examination, while using this technique yet another type of cell was differentiated (publication being prepared).In the axons-tractus starting from the pars intercerebralis special attention must be paid to the appearance of tracheoli, which due to their strong phloxinophile colour reaction could give the impression of a phloxinophile secretion.Using the same staining technique after Carnoy fixation one has no differentiation of the hematoxyline-positive secretion in an alcohol-soluble and non-soluble fraction.Staining with paraldehyde-fuchsine according toEwen (1962) confirms the conclusion of the Gomori-staining.By staining with paraldehyde-fuchsine according toHalmi (1952) no secretory products could be shown in the cells of the corpora allata in the honey bee (worker bee).The glia-elements in the neuro-endocrine system of the honey bee can be clearly differentiated by the light green acid fuchsine staining according toAlzheimer.With dark-field illumination it has been established that the cells of the pars intercerebralis in the honey bee possess light-diffusing properties. Some other parts of the brain complex however exhibit the same phenomenon, so that this technique for differentiation of the neuro-secretory cells appears to be without practical use.

     

L'aspect cytophysiologique du problème du cancer

Sans résumé     

Un nouveau système chromosomique polymorphe chez desLeggada africaines du groupeTenellus (Rodentia-Muridae)

The pigmy-mice belonging to the grouptenellus seem fairly well characterized through the structure of the teeth (M₁). However, the chromosome complement of specimens from Niamey (Niger) is strikingly different from this precedently described bytenellus from Accra (Ghana). In this last station, we had to deal with the “primitive”, complement (2N=36,N.F.=36, sex-chromosomesPR). The sample of Niamey has the following constitution: three males have 33, 33 and 32 chromosomes, the single female has 34. This robertsonian polymorphism is due to the presence either of four acrocentric autosomes, or of one submetacentric and two acrocentrics, or of two submetacentrics. This polymorphism is fundamentally alike to that demonstrated precedently in the groupminutoides. The sex-chromosomes are of primitive type (PR). Two autosomes of medium size are satellited and their metacentricity seems to result from a pericentric inversion increasing theN.F. of two, 38 instead 36.     

Le système nerveux des cténaires

Summary Ultrastructural evidence is given of the occurrence of nervous elements in the mesoglea of Ctenophores based on the presence of the typical synapses of this phylum.In Beroids, nervous fibers from the ectodermal nerve-net cross the epithelial basal membrane and run through the mesoglea; they are devoid of any ensheathing cell. These neurites build highly differentiated synapses upon the muscles and upon peculiar cells, tentatively named mesenchymal cells.In Cydippids, nerve fibers and nerve cell-bodies have been observed in the mesoglea of the tentacles. The mesogleal core of each tentacle contains mesenchymal cells and a thick strand of neurons and neurites, forming a kind of elongated ganglion. Neurites of either the axial neurones or the epithelial nerve-net neurones form numerous radial nerve strands across the tentacular muscles. Interneural, neuro-muscular and neuro-mesenchymal junctions are very frequent in the tentacle.As far as the organization of the mesoglea is concerned, the Ctenophora thus appear closer to Turbellaria than to Cnidaria.

Ce travail a bénéficié de la collaboration technique de Madame J. Amsellem que nous remercions vivement.     

Sur le système des monocotyledonées

Sans résumé     

Sur le système des monocotyledonées

Sans résuméLa première note voir: 1909, nr. 1, pag. 15.     

Hypothèses sur la génétique formelle du système Gm chez les caucasiens

Sans résuméAvec 6 Figures dans le TexteTravail réalisé avec l'aide de l'I. N. S. E. R. M. et de la Caisse Nationale de Sécurité Sociale.     

Nouveau système de marquage chromosomique: les bandes T

Two new techniques of controlled thermic denaturation are described. They especially show a staining of some terminal regions of chromosomes (terminal bands or T bands). — The application of these techniques to translocations, hardly analysable by the other banding techniques, allow the precise location of juxtatelomeric break points.