Gyrodactylus onegensis sp. n. (Monogenea)--a parasite of the bullhead (Cottus gobio L.)

A new species, Gyrodactylus onegensis sp. n., is described from gills of the freshwater sculpin Cottus gobio.     

History of fish parasitic fauna formation in water reservoirs of European North

The fauna of fish parasites in water bodies of the European North was formed in the Holocene by species immigrated from adjacent regions. The Volga River basin played a very important role in the history of the formation of fauna in water bodies of the European North (North Dvina and Onega river basins, Onega and Ladoga lakes), because there were wide connections between them in the postglacial period.     

Anticalcium activity of several antidepressive agents]

In experiments in white mice and rats the antidepressants pyrazidol (pirlindole), moclobemide and especially tetrindole possess anticalcium activity in tests of calcium chloride-induced lethality in mice and arrhythmia in rats. Tetrindole is as active as verapamil. Imipramine, azaphen and incazane were not active in these experiments. In vitro on isolated intestinal segments of guinea-pigs tetrindole exerts anticalcium action, but in less degree than verapamil. In all probability the anticalcium activity of tetrindole may play some role in the mechanism of action of this compound on the central nervous system.     

Change in the rhythm of the enzyme activity of the liver in white rats during the chronic action of vinylacetate]

Experiments were conducted on male albino rats for 5 months; the activity of the liver aspartic and alaninaminotransferases underwent cyclic synchronized variations. Chronic 24-hour inhalation of vinylacetate in a concentration of 2.4 mg/m3 caused a transformation of the rhythms of these variations with the preservation of synchronization in the changes of the activity of the enzymes under study. With a greater concentration of vinylacetate (13.2 and 68 mg/m3) inducing chronic intoxication, desynchronization of transaminase variations was seen in the liver. A posssibility of correlation analysis use for determining the extent of synchronization in the activity of the enzymatic systems for the purpose of estimation of the toxic effect of the poisons is discussed.     

The effect of gangliosides on the adhesive interaction of Neisseria meningitidis with human cells

The influence of a number of gangliosides and sialic acid on the adhesive interaction of meningococci and human cells have been studied. Sialic acid has been found to produce no influence on adhesion, and the preliminary treatment of meningococci with gangliosides or their preparations suppresses the capacity of meningococci for attachment to epithelial cells and erythrocytes. At the same time the degree of the inhibition of adhesion depends on the kind and concentration of gangliosides. On the contrary, after the treatment of target cells with gangliosides (1.25 micrograms/ml) the adhesion indices of meningococci with respect to these cells increase 5- to 8-fold. These data are indicative of the participation of gangliosides in the adhesive interaction of meningococci and human cells.