The effect of nonspecific immune stimulation with Corynebacterium parvum and polidin on the Ehrlich ascites tumor growth

Investigations were performed: a) to compare the effect of two nonspecific immunostimulants, Polidin and Corynebacterium parvum, on the development of Ehrlich ascites carcinoma in mice; b) to determine whether the effects are dependent on the tumor cell dose inoculated into the animals. C. parvum and Polidin administered prior to Ehrlich ascites tumor inoculation have a protective effect evidenced by a delay in tumor development, a retardation in tumor growth and a prolonged survival of the tumor host. The effect of immunostimulants was highly dependent on the tumor cell dose inoculated into mice and was more marked with C. parvum.     

Validation of a Commercially Available Indirect Elisa Using a Nucleocapside Recombinant Protein for Detection of Schmallenberg Virus Antibodies

A newly developed Enzym Like Immuno Sorbant Assay (ELISA) based on the recombinant nucleocapsid protein (N) of Schmallenberg virus (SBV) was evaluated and validated for the detection of SBV-specific IgG antibodies in ruminant sera by three European Reference Laboratories. Validation data sets derived from sheep, goat and bovine sera collected in France and Germany (n = 1515) in 2011 and 2012 were categorized according to the results of a virus neutralization test (VNT) or an indirect immuno-flurorescence assay (IFA). The specificity was evaluated with 1364 sera from sheep, goat and bovine collected in France and Belgium before 2009. Overall agreement between VNT and ELISA was 98.9% and 98.3% between VNT and IFA, indicating a very good concordance between the different techniques. Although cross-reactions with other Orthobunyavirus from the Simbu serogroup viruses might occur, it is a highly sensitive, specific and robust ELISA-test validated to detect anti-SBV antibodies. This test can be applied for SBV sero-diagnostics and disease-surveillance studies in ruminant species in Europe.     

Chemical protection of golden hamsters against ionizing radiation

It was shown on Golden hamsters, which are characterized by high radioresistance of the intestine, that S-2-(omega-aminopropylaminoethyl) thiophosphorous acid (gammaphos) exerts a protective action against both X- and neutron-radiation although in the latter case the protection is less pronounced. In conditions of hibernation, the protective effect of gammaphos against X-radiation was not statistically reliable. Hibernation during exposure and at the postirradiation period increases considerably the radioresistance of animals. The influence of hibernation depends upon its duration.     

Differential influence of Pomphorhynchus laevis (Acanthocephala) on the behaviour of native and invader gammarid species

Although various species of acanthocephalan parasites can increase the vulnerability of their amphipod intermediate hosts to predation, particularly by altering their photophobic behaviour, their influence on the structure of amphipod communities and the success of invader species has so far received little attention. We compared the prevalence and behavioural influence of a fish acanthocephalan parasite, Pomphorhynchus laevis, in two species of amphipods, Gammarus pulex and Gammarus roeseli in sympatry in the river Ouche (Burgundy, eastern France). There, G. pulex is a resident species, whereas G. roeseli is a recent coloniser. Both uninfected G. pulex and G. roeseli were strongly photophobic, although less so in the invading species. However, there was no significant difference in reaction to light between infected and uninfected G. roeseli, whereas infected G. pulex were strongly photophilic. We discuss our results in relation to the parasite's ability to manipulate invading host species, the possibility that resistant individuals have been selected during the invasion process, and the role that acanthocephalan parasites can play in shaping the structure of amphipod communities.     

In vitro culture of glochidia of the threatened freshwater mussel Unio crassus Philipsson 1788 – the dilution problem

We applied in vitro techniques in culturing glochidia of the thick-shelled river mussel Unio crassus, seriously threatened European species. Glochidia were freshly isolated from a gravid female. The sterile phase of the cultures was terminated at different time points to assess the optimal length of this phase. We imitated the process of juvenile excision from a fish host by diluting the culture with water at regular time intervals. The metamorphosed juveniles that survived until the end of the experiment and started growing their shells were observed for 24–27 days from the start of the culture in samples diluted for the first time between days 13 and 17. Long-lasting cultures usually became infected and died, whereas in those that were terminated too early, glochidia were unable to develop further in clean water. The transfer of juveniles from an artificial medium to pure water should be done gradually, through a series of dilutions, so that the larvae have the opportunity to feed on the diluted medium after metamorphosis. Only individuals with an active foot capable of operating outside the shell were ready to inhabit water and forage on solid food from the external environment.     

Inherent behavioral activity of rats administered different fractions of brain-specific S-100 proteins

The intraventricular injection of brain specific S-100 proteins leads to the prolonged heterochronous changes of the inherent rat behaviour forms during the period of water and food needs restitution. The effects of various doses of S-100 proteins fractions on the behavioural activity differs in the degree of expression and in time of their onset. The specific influence of some S-100 proteins fractions on duration of the different inherent forms of rat behaviour can be explained by plurality of molecular mechanisms of their effects.     

Placebo-controlled study of effects of epimestrol on the pituitary-testicular axis in normal men

Twenty healthy male volunteers were randomly allocated to the treatment with either 15 mg/day of epimestrol or placebo for 10 days. The plasma levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), oestradiol (E2) and prolactin (PRL) were measured before, during and 4 days after the medication by radioimmunoassays. Data were statistically evaluated by means of an analysis of covariance. Circulating LH and FSH, and also T and E2 significantly increased in the epimestrol treated subjects. In the placebo treated subjects no significant changes in the plasma hormone levels were observed. There were no significant changes in the plasma levels of PRL in either group.