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Notwithstanding the availability of effective vaccines, 40 - 60 thousand rabies cases in humans are reported every year. Almost always the disease is fatal because therapeutic treatment of lyssavirus encephalitis has not been developed. Since 1970 the number of reports on rare cases of convalescence including those using experimental treatment protocols has been gradually increasing 20 cases of convalescence, “partial” convalescence or long-term survival of humans (1970-2015) were selected as they were complaint with laboratory criteria of active lyssavirus infection. Children and teenagers were predominant in the analyzed group (85%). The cases were irregularly spread between the continents: Asia - 6 cases, North America - 6 cases, Africa - 2 cases and Europe - 1 case. India and the USA were on the top of the list of countries by the number of described cases. More than 60% humans were infected from dogs, three cases got infection from bats and 2 cases were allegedly associated with an unknown lyssavirus and an unidentified infection source. 70% cases were vaccinated and 10% cases were treated with gamma globulin before the disease onset. Serological tests for detection of antibodies to lyssaviruses in cerebrospinal fluid of infected humans were typically used for diagnostic laboratory verification. Less than 30% IFA and PCR positives were obtained. Lyssaviruses were never detected. Only 4 convalescent patients were treated using experimental protocols. 80% cases demonstrated severe neurological consequences, four (may be more) patients died afterwards within the period from two months to four years. Different perspectives on prospects of Milwaukee protocol use and other therapeutic techniques are given.

This work presents the results of the molecular genetic research on genomes of field isolates of the rabies virus circulating in the territory of the Kirov region in order to analyze the phylogenetic relationship between the wild isolate genomes and to determine the possible reversion of the vaccine strain of the rabies virus used in the oral vaccine to virulent variant. We studied 24 brain samples from wild carnivores shot after oral immunization of the area with Rabivak-O/333. A bait with the vaccine provided by the Veterinary Service of the Kirov was also studied. All samples were found to be positive for the presence of the rabies virus as established by FAT and RT-PCR techniques. Phylogenetic analysis of N genome fragments of the rabies virus showed that the field isolates from the Kirov regions were genetically close to the field isolates from Buryatia 2012. Analysis of G genome fragments showed that the Kirov field isolates were close to the isolates from Lipetsk (2011), as well as to the Ukrainian isolates (2006 and 2010). Molecular genetic analysis of the gene fragments N and G for the field isolates and fragments of the genome of the rabies virus vaccine did not reveal any reversion to the virulent vaccine strain.Статья посвящена молекулярно-генетическому исследованию геномов полевых изолятов вируса бешенства, циркулирующих среди диких животных на территории Кировской области, с целью проведения филогенетического анализа и определения возможной реверсии вакцинного штамма вируса бешенства, используемого при оральной вакцинации, к вирулентному варианту. Исследованы 24 образца мозга от диких плотоядных, отстреленных после проведения на этой территории оральной иммунизации вакциной Рабивак-О/333, а также приманка с вакциной, предоставленные Кировской ветеринарной службой. Методами флюоресцирующих антител и обратнотранскриптазной полимеразной цепной реакции было установлено, что все предоставленные образцы содержат вирус бешенства. Филогенетический анализ фрагментов гена N показал генетическую близость кировских полевых изолятов к изолятам, выделенным в Бурятии, анализ фрагментов гена G продемонстрировал генетическую близость кировских полевых изолятов к изолятам, выделенным в 2011 г. в Липецке, а также к украинским изолятам 2006 и 2010 гг. В ходе молекулярнобиологического анализа фрагментов генов N и G полевых изолятов и генома вакцинного вируса бешенства установлено, что в данном случае реверсия вакцинного штамма к вирулентному варианту отсутствует.

Five hybridomas secreting monoclonal antibodies (MAbs) for the nucleocapsid protein of the rabies virus were obtained through the fusion of the SP2/0 murine myeloma cells with splenocytes of BALB/c mice immunized with fixed rabies virus (CVS strain). All hybridomas secret MAbs of the IgG class that display different specificity to the nucleocapsids of rabies and rabies-related viruses. MAbs 2ell showed the specificity for the prevalent in Russia rabies viruses that are similar to commercially available anti-rabies conjugate.

The aim of the present study was to compare genotoxicity induced by high- versus very low dose-rate exposure of mice to γ-radiation within a dose range of 5 to 61 cGy using the single-cell gel electrophoresis (comet) assay and the micronucleus test. CBA/lac male mice were irradiated at a dose rate of 28.2 Gy/h (high dose rate) or 0.07 mGy/h (very low dose rate). The comet assay study on spleen lymphocytes showed that very low dose-rate irradiation resulted in a statistically significant increase in nucleoid relaxation (DNA breaks), starting from a dose of 20 cGy. Further prolongation of exposure time and, hence, increase of a total dose did not, however, lead to further increase in the extent of nucleoid relaxation. Doses of 20 and 61 cGy were equal in inducing DNA breaks in mouse spleen lymphocytes as assayed by the comet assay. Of note, the level of DNA damage by 20–61 cGy doses of chronic irradiation (0.07 mGy/h) was similar to that an induced by an acute (28.2 Gy/h) dose of 14 cGy. The bone marrow micronucleus test revealed that an increase in polychromatic erythrocytes with micronuclei over a background level was induced by very low-level γ-irradiation with a dose of 61 cGy only, with the extent of the cytogenetic effect being similar to that of 10 cGy high-dose-rate exposure. In summary, presented results support the hypothesis of the nonlinear threshold nature of mutagenic action of chronic low dose-rate irradiation.

The results of investigation of molecular genetic and cytogenetic characteristics of CBA/lac male mice exposed to continuous very low dose rate gamma-radiation (0.17 cGy/day) during 40, 80, 120, and 210 days are presented in this study. Total accumulated doses were 6.8, 13.6, 20.4, 35.7 cGy, respectively. The parameters studied were levels of DNA-protein cross-links (DPCs) and DNA breaks in spleen lymphocytes (SLs), as well as percentage of bone marrow polychromatic erythrocytes with micronuclei (MNPCEs) and peripheral blood normochromatic erythrocytes with micronuclei (MNNCEs), using the DNA precipitation, the DNA alkali unwinding, the single cell gel electrophoresis (comet) assays and the micronucleus test, respectively. In addition, the induction of DNA damage in SLs after incubation with hydrogen peroxide (H2O2 at 0.1-5 mM) was studied. An increase in the sensitivity of SLs to H2O2 was revealed at 40 days of irradiation (6.7 cGy) as compared to SLs from non-irradiated control animals. However, after 120 days of exposure to radiation (20.4 cGy), SLs became more resistant to H2O2 treatment. This effect could be attributed to a development of adaptation processes triggered upon accumulation of a certain dose (in our experiments it is ~20 cGy). Beginning from 80 days of irradiation (13.6 cGy), an increased level of DNA relaxation was observed, most likely indicating the induction of proliferation of SLs. Noteworthy is that populations of cells with markedly high level of DNA damage and apoptotic cells were registered. A level of DPCs in SLs was increased at 40 days of point only. No increase in bone marrow MNPCE or peripheral blood MNCCE in mice continuously exposed to very low-dose rate radiation was registered as compared with non-irradiated mice.

We examined the effects of nickel sulfate at doses 0.5 to 5.0 mg/kg (1/200–1/20 LD50) on the frequency of dominant lethal mutations and double-strand DNA breaks (DSBs) in germline cells and on an increase in frequency in gene mutations Wy in pigment cells of first-generation mice. The results indicated that spermatogenesis stages most sensitive to nickel sulfate (at a dose of 1.0 mg/kg) are spermatozoids, early spermatids, late spermatocytes, and stem spermatogonia. No statistically significant increase in the total TSB level was detected in spermatozoids 4 weeks after exposure. At the same time, a significant (P < 0.05) increase in percentage of cells with an extremely high level of DNA fragmentation (supposedly apoptotic cells) was observed upon exposure at a dose of 0.5 mg/kg. Nickel sulfate at doses of 5.0 and 1.0 mg/kg induced a marked increase in the c-kit gene expression in pigment cells of heterozygous first-generation WR mice as compared to control (P < 0.001). It was shown that the nonobservable adverse effect level (NOAEL) of nickel sulfate on the dominant lethal mutation frequency and gene mutations was 1/200 LD50, while the lowest observable adverse effect level (LOAEL) was 1/100 LD50.