Nine new polymorphic microsatellite loci for the amplification of archived otolith DNA of Atlantic cod,Gadus morhua L.

Nine out of 22 microsatellite primers tested were successfully amplified on three samples of cod Gadus morhua L. (two contemporary and one archived otolith samples). All loci were polymorphic (5–23 alleles/locus). The average observed heterozygosity across loci and samples was 0.625, ranging from 0.294 to 0.895 at each locus. All loci were under Hardy–Weinberg equilibrium, except PGmo56 that showed significant excess of heterozygotes in all studied samples. The isolated loci were suitable for degraded DNA and therefore useful for conducting a long‐term temporal study with DNA obtained from archived otoliths of cod.     

Biological properties of opportunistic enterobacteria isolated from the blood of patients

The comparative study of the signs of pathogenicity in enterobacteria (119 strains) isolated from the blood of 145 patients with the clinical symptoms of sepsis and from the feces of healthy persons (560 strains from 220 persons) has demonstrated that the same species of opportunistic microorganisms may essentially differ in the formation of DNase, RNase, as well as in their capacity for the positive reaction with Congo red. The possibility of using the above-mentioned signs of pathogenicity for diagnostic purposes as additional signs for the differentiation of virulent cultures of opportunistic enterobacteria from avirulent ones is suggested.     

Biological properties of opportunistic enterobacteria isolated from healthy persons and from patients with intestinal dysbacteriosis

The comparative study of the signs of pathogenicity in 724 enterobacterial strains and in some species of nonfermenting microorganisms isolated from the feces of 115 somatic patients with intestinal dysbacteriosis and 80 healthy persons (565 strains) has revealed that microorganisms belonging to the same species may essentially differ in their occurrence, in the activity of the enzymes (DNAase, RNAase, phosphatase) which they release into the culture medium, as well as in their capacity to give the positive reaction with Congo red. At the same time, the cultures isolated in cases of intestinal dysbacteriosis have been found to be biologically more active.     

Comparative assessment of percutaneous transhepatic cholangiodrainage under roentgenoscopy and ultrasound guidance

In 1990-2000, percutaneous transhepatic cholangiodrainage was performed in 89 patients with obstructive jaundice of tumoral etiology: Groups A (n = 21) under roentgenoscopic guidance and Group B (n = 68) under ultrasound guidance (USG). The efficiency and safety of puncture of the biliary tract were comparatively evaluated in these groups. The technical success of the procedure was achieved in 81.0% of Group A patients and in 98.5% of Group B ones. USG decreased radiation load on the patient and medical staff by three times and the number of needle passes by two times. External-and-internal cholangiodrainages under USG and roentgenoscopy were performed in 55.2 and 23.8%, respectively. The incidence of complications and mortality were 5.9 and 1.5% in Group B and versus 17.6% and 4.8% in Group A. It is concluded that transhepatic cholangiodrainage under USG has some advantage over puncture of the biliary tract under roentgenoscopy.     

Identification of radiation,chemical and combined effects on natural populations of aquatic organisms

Approaches to the identification of radiation, chemical and combined effects on natural populations of aquatic organisms are proposed. These approaches are based on generalization of our previous experimental data concerning separate and combined effects of ionizing radiation and chemical mutagens (heavy metals and chlororganic compounds) on crustaceans and fishes embryos, as well as on results of field studies carried out before and after the Chernobyl NPP accident. For the identification of damaged factors it is proposed to use the following criteria: a comparison of cytogenetic effects in mutagen equivalent doses, a distribution of chromosome aberrations in cells and a number of aberrations per an aberrant cell.     

Cytogenetic and population effects in oligochaeta from the Chernobyl zone

Research on intensity and character of reproduction of Oligochaeta (Dero obtusa, Nais pseudobtusa and Nais pardalis) was carried out in 1995-1996 in two water-bodies: a) in the Chernobyl NPP zone near Yanov Village, with a dose rate of 14 microGy h-1 on the surface of the bottom sediment; b) at the Uzh River area (the control water-body). The changes in both intensity and reproduction type were observed in worms at the radioactively polluted water-body. Stimulation of paratomic division in D. obtusa as well as activation of sexual reproduction in two other species were found out along with increasing of amount of cytogenetic damages in somatic cells.     

2D QSAR studies on thyroid hormone receptor ligands

2D QSAR studies were carried out for a series of 55 ligands for the Thyroid receptors, TRalpha and TRbeta. Significant cross-validated correlation coefficients (q(2)=0.781 (TRalpha) and 0.693 (TRbeta)) were obtained. The models' predictive abilities were proved more valuable than the classical 2D-QSAR, and were further investigated by means of an external test set of 13 compounds. The predicted values are in good agreement with experimental values, suggesting that the models could be useful in the design of novel, more potent TR ligands. Contribution map analysis identified a number of positions that are promising for the development of receptor isoform specific ligands.