Quelques aspects de l'étude électrophysiologique des réceppteurs sensoiriels des antennes d'Hyménoptères

Insectes Sociaux - With a classical system of amplification and registration, we have obtained electrical responses to variaous stimuli in isolated antennae of Wasps and Bees. A very light...     

La radiation des Mammifères : phylogénie et innovations évolutives,progrès récents

The radiation of Mammals: recent advances concerning their phylogeny and evolutionary innovations. In the 3,5 billion years of the History of the Life, that of Mammals seems to us all the more brief that their future seems to have deceived in some million years, at the very beginning of the Cenozoic times. For their understanding, palaeontologists as well as molecularists try to build up the phylogenetic tree of the mammals. Here some of the reasons for the conflicts and controversies between both communities are analysed. Also the main evolutionary novelties as observed in Early Tertiary mammals are described. This catalogue shed light on this extraordinary event. To cite this article: J.-L. Hartenberger, C.R. Palevol 2 (2003).     

L'action du dioxyde de sélénium sur des œufs d'amphibiens d'espèces résistantes

The eggs of some Amphibian species (Triturus helveticus Raz., Triturus alpestris Laur., Xenopus laevis Daud.) are more resistant to selenium dioxyde M/100 than eggs of Pleurodeles waltlii Michah. Minimal mitotic abnormalities are observed: 1. “empty” poles, 2. cupular poles, 3. escape of centrosphere, which separates from the spindle, and sometimes torsion of polar regions of the achromatic figure. Cytasters and newly formed spindles are also observed in the diastematic clear zone, which is dissociated and inefficient. These abnormalities are believed to be consequences of the progressive diminution of a dominant factor associated with the centriole. When dominance is weakened, secondary poles appear with or without relation to the spindle. The balance between fibrillogenesis and reproduction of centrioles is newly demonstrated. These mechanisms are compared with phenomena occuring during fertilization and parthenogenesis     

Une syringocèle révélée par un abcès périntéal

Purpose

The authors present a clinical report of a perforate syringocele diagnosed in a male patient and they review the clinical, radiological and therapeutic aspects of this disease.

Case report

A 50-year-old man attended the emergency room with perineal abscess. Computerized Tomography (CT) scan was used to establish the diagnosis. This patient also underwent urethrocystoscopy, sonography and retrograde urethrography.

Results

Treatment consisted of open surgical evacuation of the perineal abscess with bladder catheter. Urethrocystoscopy showed a large perforate syringocele in the urethra with no need for endoscopy marsupialization. No recurrence was observed at follow-up at 3 months.

Conclusion

Syringocele is a rare malformation which usually is asymptomatic. It can be congenital or acquired and can be classified into four morphological types. The most frequent treatment is endoscopic marsupialization of the syringocèle. Open surgical excision is recommended for complicated syringocèle with abscess or perineal pain.     

La végétation pionnière des pentes sableuses sèches dans la région de Yangambi-Stanleyville (Congo Belge)

Résumé analytique Dans la région de Yangambi-Stanleyville, les pentes sableuses ou gréseuses sèches ensoleillées (falaises, talus, déblais) sont colonisées par l'association à Dicranopteris linearis (Gleichenietum linearis ass. nov.) se décomposant en une phase initiale à dominance de bryophytes et d'algues et une phase optimale à dominance de ptéridophytes dans laquelle abonde Dicranopteris linearis accompagné d'espèces pionnières des groupements forestiers de terre ferme.

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Summary In the region of Yangambi-Stanleyville, the sandy dry and sunny slopes (cliff, digging) are colonized by the Dicranopteris linearis association (Gleichenietum linearis ass. nov.) which falls into two phases: an initial with bryophytes and algae and an optimal one with predominance of pteridophytes, chiefly Dicranopteris linearis accompanied by various pioneer forest species.

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Reçu par la rédaction le 12.XII.1953.     

L'histogenèse régénératrice chez les phoronidiens

Summary The regeneration (organogenesis was studied by Emig, 1972 a, b) of Phoronida can be divided into three phases: the first one, cicatrisation, is characterized by a provisional mesodermal scar-tissue, later the old epidermis cover this scar-tissue. The regenerating blastema, second phase, takes place by cellular dedifferentiation processes; each germ layer (ectoderm, mesoderm, endoderm) regenerates itself from its own elements. One exception only seems to be oesophagel regeneration by metaplasia of the prestomacal cells during the asexual reproduction. The differentiation of the amputated structures (third phase) appears submitted to the inductive influence of the mesoderm and to the trophic action of the nervous system (especially the epithelial plexus). The polarity in regeneration sets a problem in Phoronida.

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Ce travail a été effectué dans le cadre du contrat L. A. n 41 au C. N. R. S.     

Etudes des variations des paramètres biométriques des chromatides dans des cas d'endoréduplication

Human Genetics - Ce travail comporte des analyses de la variance de la longueur et de l'indice brachial des chromosomes 1, 2 et 3, de cellules ayant subi une endoréduplication.     

Influence du facteur «exposition» sur la répartition des microhyménoptères parasites deCoccoidea-Diaspididae

Summary Climatic factors have an important influence on the efficiency of hymenopterous parasites of Coccids. Significant differences were observed in the rate of parasitism ofPseudaulacaspis pentagona Targ. by its natural enemies in different orchards or on different trees of the same orchard. In order to investigate this phenomenon, experiments were designed in which the position of parasitized hosts on the bough was taken in consideration. Analysis of host and parasite populations on the different parts of a bough show that the control byProspaltella berlesei How (Hym. Aphelinidae) is better on the shaded side; similar experiments have been undertaken withP. perniciosi prior to colonisation of this species for the Biological Control of the San José Scale.      

Techniques de préparation des microhyménoptères

Summary The author proposes to standardize the preparation technique for microhymenoptera. The insects have to be presented for identification in a dry state, mounted on a minute pin or glued on a heavy paper point (double-mounting). Preference is given to the mounting on minute pin, as this method has the advantage that a specimen pinned with a minuten may be removed from its support and each morphological detail easily observed. The minuten is fixed to a short strip of soft material such as polyporus (bracket fungus); if this is not available, stiff paper may be used. The support with the pinned specimen is then attached to a pin no. 3 (fig. 1–3). The absence of glue is advantageous, especially in subtropical countries, where the glue is generally destroyed by bacteria and fungi. When the pins are unavailable for this double-mounting technique, the author proposes to glue the thoracic pleurae of the insect to the previously folded tip of a heavy paper point (fig. 6). The material for identification may be preserved in a liquid medium (as alcohol with some drops of glycerine) after a series of individuals have been prepared according to the double-mounting technique. Also, specimens in excess may be sent dry in a plastic or glass tube between two cellucotton masses.      

Contribution a l'étude des levures des chais- taxonomie,répartition des levures

Résumé Les populations levuriennes de deux chais de Bourgogne sont étudiées sur deux années d'un point de vue taxonomique et biologique. 122 souches se rapportant à 26 espèces, ont été isolées à partir de la voûte et du sol de la cave, sur les madriers supportant les tonneaux, dans la cuve, sur le pressoir et sur les tonneaux. En dehors d'un certain nombre d'espèces classiques dans ce type d'habitat, telles que Saccharomyces cerevisiae, Pichia membranaefaciens, Hansenula anomala et Kloeckera apiculata, nous avons pu mettre en évidence notamment: Debaryomyces hansenii, Torulopsis Candida, Saccharomyces italicus, ainsi qu'un certain nombre d'espèces appartenant aux genres Pichia, Candida et Trichosporon. La répartition qualitative et quantitative des espèces est également étudiée.

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The yeast populations of two burgundy cellars were studied during two years from a taxonomical and biological point of view. 122 strains distributed among 26 species have been isolated from the vault and ground of the cellar, on the planks supporting the barrels, in the tank, on the winepress and on the barrels. Apart from a number of standard species in this type of habitat such Saccharomy cescerevisiae, Pichia membranaefaciens, Hansenula anomala, Kloeckera apiculata we have encountered the more rare Debaryomyces hansenii, Torulopsis Candida, Saccharomyces italicus as also species of the genus Pichia, Candida, and Trichosporon.