Vol 54, No 2 (2009)

In 2005 to 2007, there was a reduction in the virulence of highly pathogenic avian influenza A virus A/H5N1 genotype 2.2 strains deposited in the State Collection of Viruses of the Russian Federation. Decreased virulence was most marked in the strains from domestic birds, the least in those from wild birds. Comparison of phenotypical and molecular genetic data revealed point amino acid replacements that might affect reduced virulence.

To elucidate the role of some viral and cellular proteins in the occurrence and development of HERV-K-associated germ-cell tumors (GCT), reverse-transcription polymerase chain reaction using specific primers has been employed to study the transcription of the protein Rec HERV-K and the possible interaction of the protein Rec(cORF), that has transforming properties, and the cellular protein PLZF, that is a negative regulator of cell division, in human GCT tissues, in the testicular parenchyma adjacent to a tumor, and in the normal testicular tissues. It was shown that there was expression of Rec(cORF) of mRNA, rather than cellular PLZF in all malignant GCT tissues, this led to the conclusion that no interaction occured between the Rec HERV-K and PLZF proteins in the GCT cells. At the same time co-expression of Rec and PLZF protein was first revealed at the level of transcription in the testicular parenchyma adjacent to a tumor that exhibited carcinoma in situ cells. By taking into account that the protein Rec HERV-K has transforming activity and it is presumed to be implicated in the development of GCT, the authors discuss a possible role in the Rec HERV-K/HTDV and cellular PLZF interaction in the pathogenesis of GST at the early stages of its genesis.

The nucleotide sequence of the 5'-LTR region of provirus DNA of 45 samples of the variant IDY-A of HIV-1 subtype A, which had been isolated from seropositive persons in Russia was analyzed. The structure of 5'-LTR was shown to have a high conservatism within the subtype A. The virus variants carrying the altered TAR peg structure gained no further acceptance. An insertion of 12 p.n. was detected in the MFNLP region, which was characteristic of Russian samples of subtype A and which had an additional binding site for factor RBF-2 that was able to affect viral replicative capacities. The Sp1 (II) and AP3-like sites, binding NF-AT factor, proved to be most variable.

The new highly sensitive test system "DS-EIA-HBsAg-0.01" (Priority Certificate No. 2006129019 of August 10, 2006) in detecting hepatitis B surface antigen (HBsAg) was assessed. The sensitivity of the test was estimated using the federal standards sample HBsAg 42-28-311-06, panels' samples Boston Biomedica Inc. (West Bridgewater, Mass, USA) and ZeptoMetrix Corp. (Buffalo, NY, USA). The findings have indicated that "DS-EIA-HBsAg-0.01" is equally effective in detecting different subtypes of HBsAg during a seroconversion period earlier than alternative assays. Along with its high analytical and diagnostic sensitivity, the system shows a high diagnostic specificity.