Ultrastructure du tissu apical testiculaire du doryphore Leptinotarsa decemlineata Say (Coléoptère: Chrysomélidé): étude autoradiographique et cytochimique / Ultrastructure of the apical testicular tissue of the doryphore Leptinotarsa decemlineata Say (Coleopterae: Chrysomelidae): an autoradiographic and cytochemical study

Summary

The somatic ‘apical tissue’ is present in the testes of the Colorado potato beetle from the embryonic stage until the end of the reproductive life. In the vicinity of this tissue, cyst cells and primary gonia are often pycnotic. Incorporation of labelled amino acids in vivo and treatment with pronase indicate that apical cells are sites of protein synthesis. Secretions are glycosylated in the Golgi apparatus where they are also concentrated in granules. Some of them display a positive reaction to the acid phosphatase test. They are extruded by exocytosis into the intercellular spaces which they distend. We conclude that the apical secretions have a lytic activity: gonia and cyst cells are reduced to cellular residues which are accumulated in the intercellular spaces.     

Immunological study of a hemophiliac treated according to the Bonn protocol for 2 1/2 years

A major haemophiliac A, 27 years old, has been treated during 30 months, with high dosage of imported Factor VIII, in order to reduce the titer of a F VIII antibody. A good clinical result has been obtained. No sign of immunodeficiency has been observed. Normal values were obtained for T4/T8, ratio B2 microglobulin and no antibody was detected against the LAV virus isolated from cases of AIDS.     

Expression of laminin by human fibroblasts, HT1080 fibrosarcoma cells and MCF-7 breast adenocarcinoma cells. Lack of regulation by the cell density and extracellular matrix.

We have cultured normal fibroblasts, fibrosarcoma HT1080 cells and breast adenocarcinoma MCF-7 cells on various substrates (plastic, collagen type I, laminin). All cell types used adhered on the three substrates with, however, a delayed attachment on laminin. On all substrates, cell grew as monolayer with the exception of MCF-7 cells that formed clusters on laminin. The epithelial MCF-7 cells as well as mesenchymal cells (fibroblasts and tumoral HT1080 cells) synthesized laminin and expressed mRNA coding for laminin B1 chain and for the 67 kD laminin binding protein. The levels of these mRNAs were not modulated by culture conditions which affect cell morphology nor by cell density.     

Which adult male savanna baboons form coalitions?

We investigated the mechanism of alliance formation among adult male savanna baboons by comparing the characteristics of males that formed coalitions frequently with males that never or seldom took part in coalitions. We observed three groups: two of Papio cynocephalus cynocephalusin Amboseli National Park, Kenya, and one of P. c. anubisin the vicinity of Gilgil, Kenya. We considered four hypotheses: (1) Males must be familiar with each other, (2) males must have an affinitive bond, (3) males must have more than average experience, and (4) the combined fighting ability of the coalition partners relative to the fighting ability of their opponent determines the likelihood that a coalition is formed. We conclude that relative fighting ability forms the key factor in coalition formation. High- ranking males do not form coalitions often, since they hardly need them. Low- ranking males rarefy form coalitions, since they cannot form effective coalitions among themselves. Affinity (“friendship”) may play a role as an additional factor. The relation of coalition formation with age and period of residence, which was found in several studies, can be explained largely by the correlation between these parameters and fighting ability.