Antibodies to meningococcal lipopolysaccharide in different forms of meningococcal infection

The results of the determination of antibodies to lipopolysaccharide (LPS) in 270 patients with different forms of meningococcal infection and in 816 healthy persons by means of the passive hemagglutination test are presented. The role of antibodies to LPS in the formation of humoral immunity to meningococci in sick children and adults is shown. Different forms of meningococcal infection have been found to have their specific features of the accumulation of antibodies to LPS. As revealed, the time of the sanation of liquor and the level of antibodies to LPS are unrelated, which indicates that antibodies to LPS may play some role in the pathogenesis of meningococcal infection.     

Prevalence of the gene encoding the outer membrane lipoprotein LipL32 in leptospires of different taxons

Primers flanking the fragment sized 677 bp have been constructed on the basis of nucleotide sequences of the gene encoding the outer membrane lipoprotein LipL32. PCR-analysis was used to reveal the prevalence of gene lipL32 among 73 Leptospiraceae family strains representing different genera and genomic species. The gene lipL32 appeared to be conservative across the pathogenic species. In contrast, it was not detected in the genome of nonpathogenic free-living leptospires. Thus the developed PCR test-system with primers LEP21/LEP22 may be efficiently used to differentiate these two distinct ecological groups of leptospires.     

Characteristic parameters of the vascular-platelet component of the hemostasis system in the immigrant and indigenous populations of the Far North

The platelet aggregation activity was studied in 79 healthy subjects, immigrant and indigenous, aged between 20 and 59 years, living in the Yamalo-Nenets Autonomous Area. The platelet count and spontaneous and induced platelet aggregation were assessed using the inducer adenosine diphosphate (ADP). It was established that the spontaneous platelet aggregation rate was higher (p < 0.01) in indigenous residents of the region than in the immigrant population, and the ADP-induced platelet aggregation values were higher in the immigrant population of the Far North (p < 0.01).     

Chemiluminescent multiassay of pesticides with horseradish peroxidase as a label

Competitive chemiluminescent immunoassay based on a combination of five antibodies was used in a combination with neural network to identify and estimate amounts of three cross-reacting s-triazines (atrazine, terbythylazine and ametryn). Antibodies with different cross-reactivity towards s-triazines were immobilized in separate wells an eight-well microtiter strip. Training of neural networks was carried out with four different learning procedures. The best topology for the data measured was a net with two hidden layers with ten neurons in the first and 15 in the second layer trained with the Schmidhuber method. s-Triazine classification of environmental samples containing various analyte mixtures was correct in 70-100% of all cases depending on the type of analyte. The test developed can be proposed as an alternative field test for multianalyte environmental monitoring.     

Production of recombinant hIL-4delta2-a native isoform of human interleukin-4 in Escherichia coli cells

Expression plasmids containing the synthetic gene hil-4 delta 2 was constructed to produce human interleukin-4 in Escherichia coli cells. Strains TG1 (pBTIL-4 delta 2) and BL21 (DE3) (pETIL-4 delta 2) produced the recombinant protein as inclusion bodies, and its production level was up to 30% of the total cell protein. The renatured hIL-4 delta 2 inhibited IL-4-stimulated T cell proliferation, and this effect was enhanced by cyclosporin A.