[Mechanism of cytotoxicity of artificial ribonucleases in various human cancer cell lines].

The ability of artificial ribonucleases to cause in the concentration-dependent manner death of cancer cells has been studied. The cytotoxic activity of artificial ribonucleases is observed at rather low concentration of these compounds (10(-5) M). Analysis of the mechanism of artificial ribonucleases cytotoxicity revealed that compounds under the study exhibit membranotropic activity in addition to ribonucleases activity found earlier. This activity is responsible for effective penetration of these compounds inside cells. The results obtained show that artificial ribonucleases induce cell death via damage of cells membrane, detachment of plasmalemma and derangement its macromolecular organization. In the case of short-term exposure of cells to the compounds, cells, even with damaged membrane, survive.

[Orthopoxvirus genes for kelch-like proteins. III. Construction of mousepox (ectromelia) virus variants with targeted gene deletions].

Mousepox (ectromelia) virus genome contains four genes encoding for kelch-like proteins EVM018, EVM027, EVM150 and EVM167. A complete set of insertion plasmids was constructed to allow the production of recombinant ectromelia viruses with targeted deletions of one to four genes of kelch family both individually (single mutants) and in different combinations (double, triple and quadruple mutants). It was shown that deletion of any of the three genes EVMO18, EVM027 or EVM167 resulted in reduction of 50% lethal dose (LD50) by five and more orders in outbred white mice infected intraperitoneally. Deletion of mousepox kelch-gene EVM150 did not influence the virus virulence. Two or more kelch-genes deletion also resulted in high level of attenuation, which could evidently be due to the lack of three genes EVM167, EVM018 and/or EVM027 identified as virulence factors. The local inflammatory process on the model of intradermal injection of mouse ear pinnae (vasodilatation level, hyperemia, cutaneous edema, arterial thrombosis) was significantly more intensive for wild type virus and virulent mutant deltaEVM150 in comparison with avirulent mutant AEVM167.

[Investigation of the impact of cowpox virus BTB/kelch gene deletion on some characteristics of infection in vitro].

The biological properties of cowpox virus (CPXV) mutants with target deletion of 4 of the 6 BTB/kelch genes (D11L, C18L, G3L, and A56R) were examined in CV-1 cell cultures. There were changes in mutant temperature sensitivity and a reduction in a viral cytopathic effect. The mutant-infected culture yielded a smaller number of cells with actin-related long cellular protrusions (63 of 300 cells) as compared with wild CPXV (127 of 300). The length of the protrusions was 20-60 and 40-120 microm, respectively). Confocal microscopy revealed the formation of large globed structures containing both actin and CPXV antigens in the cells infected with quadruple mutants. These globed structures were recognized as incomplete protrusions. The findings show that the formation of long protrusions in the cells infected with wild type CPXV represents a type of specific viral potency related to the activity of BTB/kelch genes whose deletion results in cellular insufficiency to form full-fledged protrusions.

[Comparative analysis of the susceptibility and productivity of respiratory tract target cells of mice and rats exposed to inflienza virus in vitro].

The levels of susceptibility to influenza virus A/Aichi/2/68 H3N2 and the virus yield were determined using primary cells of the trachea and lungs of CD-1 mice and Wistar rats, and for 3 sets of cells obtained from primary lung cells of the both species by centrifugation in the gradient of density and by sedimentation on a surface. The values of ID50 virus dose for 10(6) cells and virus yield per 1 infected cell determined for primary mice cells were 4.0+/-0.47 and 3.2+/-0.27 IgEID50 (lung cells), 3.8+/-0.17 and 3.3+/-0.20 IgEID50 (tracheal cells), and those determined for primary rat cells were 4.0+/-0.35 and 2.1+/-0.24 IgEID50 (lung cells), 3.7+/-0.27 and 2.2+/-0.46 IgEID50 (tracheal cells). The values of ID50 and yield measured for mixtures of cells obtained from primary lung cells by centrifugation in gradient of density and by sedimentation on a surface differed insignificantly (p = 0.05) from the values of the corresponding parameters measured for lung and tracheal cells for both rats and mice. The analysis of data on the variation of the concentrations of different cell types in the experimental cell mixtures shows that type 1 and 2 alveolocytes possess significantly lower (p = 0.05) susceptibility and productivity vs. ciliated cells of the both species. The investigation was conducted within the frame of the ISTC/DARPA#450p project.

[The new eubacterium Roseomonas baikalica sp. nov. isolated from core samples collected by deep-hole drilling of the bottom of Lake Baikal].

Microbiological analysis of samples of sedimentary rocks from various eras of the geological history of the Baikal rift has enabled us to isolate a large number of microorganisms that can be classified into new, previously undescribed species. The present work deals with the identification and study of the morphological, biochemical, and physiological properties of one such strain, Che 82, isolated from sample C-29 of 3.4-3.5 Ma-old sedimentary rocks taken at a drilling depth of 146.74 m. As a result of our investigations, strain Che 82 is described as a new bacterial species, Roseomonas baikalica sp. nov., belonging to the genus Roseomonas within the family Methylobacteriaceae, class Alphaproteobacteria.

[Reproduction of cowpox virus strain EP-2 isolated from an elephant in primary fibroblast cultures and chorion-allantoic chick embryos].

Electron microscopy was used to study the reproduction of cowpox virus strain EP-2 in the cells of a primary fibroblast cultures (PFC) and chorion-allantoic membrane (CAM) of chick embryos (CE). The sequential stages of viral morphogenesis and the structure of A-type inclusions were described. The parameters of viral reproduction in PFC and CE CAM were compared. The formation of crystalloid tubular structures in PFC, unusual electron dense inclusions in the cells of CE CAN, and different variants of A-type inclusions in the cells of a pock was found. The histological and ultrastructural characteristics of pocks in CE CAM are described.

[Isolation and characterization of bovine diarrhea viral isolates].

The paper presents the results of a study of the antigenic and electromicroscopic characteristics of 3 bovine viral diarrhea isolates from cattle in Siberia. All the isolates were antigenically related to the reference strain BK-1 and closely interrelated: their affinity was in the range of 92.2 to 96.4%. The aerosolic administration of the isolate of TM from the sick calf lung into 2 seronegative (4-6-month-old) calves caused the characteristic sings of acute respiratory disease with short diarrhea.

[Preclinical studies of the anticancer adenovirus cancerolysin preparation].

The anticancer drug Cancerolysin has been developed, by using the mutant Adel2 variant of human adenovirus serotype 5 designed at the State Research Center of Virology and Biotechnology. Cancerolysin possesses a high degree of replication activity for complementary cells 293 and p53-deficient tumor cells and, at the same time, has significant replication limitations in normal human cells. Preclinical studies of the drug on laboratory animals (mice, rabbits, guinea pigs) have demonstrated its harmlessness and safety. When stored at -40 and -70 degrees C, the drug showed no significant activity throughout the control observational period (1 year).

[Intranasal infection in mice inoculated with cowpox virus strain EP-2 isolated from the elephant].

The specific features of reproduction of EP-2 strain of cowpox virus (CPV) were studied in intranasally infected BALC/C mice by light and electron microscopy. Virus replication was found in the ciliated, intercalary, basal, and goblet cells (the nasal respiratory area), basal and supporting cells (the nasal olfactory area), ciliated, intercalary, goblet cells (the tracheal and bronchial epithelium), and collagen-producing, Schwann's, endothelial, smooth muscle, and adventitial cells. It has been shown that the CPV strain EP-2 locally replicates in the nasal cavity, trachea, and large bronchi and that there is no generalized infection.

[The carnivorous fungi hyphomycetes are natural regulators of the size of animal parasitic nematodes].

The carnivorous fungi hyphomycetes are natural enemies of soil nematodes. Laboratory tests examining the effect of the effective strain Duddingtonia flagrans T-89 on equine strongyle larvae have indicated that their size can be reduced 5-48-fold under the action of the fungus. Using helminth-infected mice as an example has ascertained that when the animals are fed a biopreparation, the chlamydial spores of the carnivorous fungus D. flagrans remain viable and continue their development in the excrements. The dead nematodes show cell structural impairments in all tissues and organs, which may be associated with the action of the substances contained in the cell envelope of the fungus.

[Genomic and phenotypic analyses of microorganisms isolated from the sediments of Lake Baikal].

Genetic and biochemical methods and morphological examination were used to study microorganisms isolated from samples of deep drilling of the Lake Baikal bottom sediments. Based on blot hybridization patterns, the strains investigated were divided into several groups according to the degree of homology of their genomic DNA. Morphological, biochemical, and ultrastructural characteristics of bacterial strains are described, and their compliance with the genomic analysis data is demonstrated.

[A new setup for the generation and studies of mono-disperse microbiological aerosols in medical-and-biological research]. / Novyi kompleks dlia polucheniia i izucheniia monodispersnykh mikrobiologicheskikh aérozolei v mediko-biologicheskikh issledovaniiakh.

A setup for the generation and studies of mono-disperse microbiological aerosols is described in the paper. Coefficients of 3 microm aerosol deposition in the respiratory tract of mice and rats were refined by using the above setup. The probability of deposition of such particles in the trachea and lungs of mice was proven to be equal to 1.2 +/- 0.1% and 2.6 +/- 0.2%, respectively. The probability for rats was equal to 3.2 +/- 0.2 and 11.8 +/- 0.9%, respectively. The distribution of deposited aerosol particles was determined by electron microscopy.

[Pulmonary cell susceptibility in mice and rats to influenza virus when infected in vivo and in vitro]. / Vospriimchivost' kletok legkikh u myshei i krys k virusu grippa pri infitsirovanii in vivo i in vitro.

The purpose of the case study was to evaluate comparatively the relative contribution of cell susceptibility and the inhibiting effect of factors of pulmonary epithelial lining in mice and rats to influenza virus A/Aichi/2/68 (H3N2) adapted to mice as related with the development of infection process in the lungs of experimental animals when infected in vivo and in vitro. Mice and rats were infected aerogenically with different doses of influenza virus. The primary cell-culture suspensions sampled from the lungs of mice and rats were used to study the adsorption and dynamics of influenza virus production in infection by different dose of influenza virus in vitro. The cell suspensions were shown to be able to produce the influenza virus for as long as 48 hours after infection. It was for the first time that the results denoted the identical susceptibility of primary pulmonary cells in mice and rats to influenza virus. A lower pulmonary susceptibility to influenza virus in rats versus mice could be indicative of that the surface factors of epithelial lining contribute essentially to shaping the pulmonary susceptibility to influenza virus since there is no difference of the susceptibility of pulmonary cells to influenza virus between the two above animals' species.

[An experimental infection caused by the EP-2 strain of cowpox virus in mice of different ages]. / Eksperimental'naia infektsiia, vyzyvaemaia shtammom EP-2 virusa ospy korov, u myshei raznogo vozrasta.

The specificity of lethal infection was studied in noninbred white mice (age--15 to 20 and 25 to 30 days) infected intraperitoneally with the EP-2 strain of cowpox virus (CPV) in doses 10(5), 10(6) and 10(7) PFU. The virus caused the lethal infection in the 15-20-day mice; while the 25-30-day mice remained healthy and survived. Virologic, immunologic-and-histochemical and electron-microscopy examinations of the 15-20-day mice revealed a replication of the EP-2 strain in tissues bordering on the virus introduction area; there was no generalization of infection. The virus replicated first in the mesothelium cells, and after that, in fibroblasts as well as in the endothelial, fatty, adventicial, cross-striated and muscle cells and in myosatellites.

[The study of orthopoxvirus genes for Kelch-like proteins. II. Construction of cowpox virus variants with targeted gene deletions]. / Izuchenie ortopoksvirusnykh genov, kodiruiushchikh Kelch-podobnye belki. II. Sozdanie variantov virusa ospy korov s napravlennymi deletsiiami genov.

Integrative plasmids p delta C, p delta D, and p delta G were designed to contain a selective marker beyond the region of homology to virus DNA and to allow construction of recombinant cowpox viruses (CPV) that lack C18L, D11L, or G3L coding for kelch-like proteins. CPV mutants lacking one (C18L, D11L, or G3L), two (D11L/G3L or C18L/D11L), or three (D11L/G3L/C18L, that is, all) kelch-like protein genes of the left variable region of the virus genome were obtained. Impaired reproduction was observed for the triple mutant. Pocks produced by the triple mutant and the original virus differed in size and morphology. In addition, the two CPV variants differed in destructive changes caused in the chorioallantoic membrane of chicken embryos.

[Identification of chlamydia and (or) chlamydia-like microorganisms by light microscopy confirmed by electron microscopy and fluorescent in situ hybridization]. / Rasprostranennost' khlamidii i (ili) khlamidiepodobnykh mikroorganizmov u zhenshchin po rezul'tatam svetovoi mikroskopii, podtverzhdennym électronno-mikroskopicheski i s pomoshch'iu FISH-gibridizatsii DNK.

Using light microscopy, we have shown that chlamydia and/or chlamydia-like microorganisms are registered in 20-25% of the healthy part of human population, whereas in patients of the same age with gynecological problems these were found in 40-50%. Commonly, the infection was slightly manifested (less than 5% of cells are infected). These results were confirmed in four months but only in heavily infected patients. The light microscope data are confirmed by observations with electron microscopy, and by FISH hybridization of the total chlamydial DNA on cytological preparations with chlamydial inclusions. In some cases, microcolonies revealed by FISH hybridization occupied the majority of the cytoplasm volume. Occasionally, the DNA material was found on the nuclear surface. It seems likely that in heavily infected cells chlamydia are able to penetrate into the perinucular space.

[Submicroscopic characteristics of Marburg virus and its mini genome analog replication in cell cultures]. / Submikroskopicheskie osobennosti replikatsii virusa Marburg i ego mini-genomnogo analoga v kul'turakh kletok.

Marburg virus (Filoviridae) causes severe hemorrhagic fevers in humans and some lower primates with high mortality. The virus genome is formed by a single strand RNA of negative polarity, coding for seven structural proteins. We studied the ultrastructure of Marburg virus replicative cycle and replication of its minigenome RNA (coding for the terminal areas of the genome) in the presence of helper virus in VERO fibroblastoid cell culture and epithelioid MDCK cell culture. Ultrastructural parameters of Marburg virus multiplication in these cell cultures are virtually the same. The virus nucleocapsid assembly is performed on the outer side of EPR membrane and is not associated with preliminary accumulation of the precursor material. Virions form by budding on plasmalemma and are located on the entire surface in Vero cells and only on the basolateral surface of MDCK cells. Replication of minigenome analog of marburg virus is associated with impairment of the helper virus morphogenesis and formation of spherical pseudoviral particles.

[Comparative study of the morphology and antigenic properties of recombinant analogs of a Marburg virus nucleoprotein]. / Sravnitel'noe izuchenie morfologii i antigennykh svoistv rekombinantnykh nalogov nukleoproteina virusa Marburg.

The full-length gene for Marburg virus (MV) nucleoprotein (NP) was cloned in prokaryotic pQE32 under the control of the T5 promoter and in eukaryotic pTM1 under the control of the promoter for T7 RNA polymerase. Recombinant NP was synthesized in Escherichia coli and in human kidney cell line 293 cotransfected with recombinant vaccinia virus vTF7-3 expressing T7 RNA polymerase. On evidence of electron microscopy with immune detection, recombinant NP formed tubules of two types in E. coli and of a single type in cell line 293. ELISA and immunoblotting with polyclonal and monoclonal antibodies revealed common antigenic determinants in recombinant NP and natural MV NP.

[Comparative analysis of methods of diagnosis of chlamydia infection]. / Sravnitel'nyi analiz metodov diagnostiki khlamidioza.

In case of a correct sampling, the diagnostic value of optic and electron microscopy for detecting Chlamydia infection is not inferior to that of direct microimmunofluorescence (DMIF) and higher than that of enzyme immunoassay (EIA). Optic microscopy showed that basal vaginal epithelium and buccal mucosa can be infected with Chlamydia. Provazek bodies were detected in the buccal mucosa of the overwhelming majority of patients with genital chlamydiasis. These results were confirmed by DMIF and EIA. Since none of the diagnostic methods is 100% reliable, we recommend using two methods: inexpensive optic microscopy and polymerase chain reaction or DMIF.

[Localization of immunodominant antigens of the liver fluke Opisthorchis felineus by immunoelectron microscopy]. / Vyiavlenie lokalizatsii immunodominantnykh antigenov v maritakh Opisthorchis felineus s pomoshch'iu immunnoi élektronnoi mikroskopii.

Immune electron microscopy with a panel of monoclonal antibodies to O. felineus antigens and human immune sera from patients was used for localization of the main antigens of adult O. felineus. The immune complexes at the ultrastructural level were visualized by 5-nm colloidal gold. The main antigens recognized by human antibodies and monoclonal antibodies were associated with the tegument, muscles, uterus, gonads, intestine and eggs of the liver fluke. The findings led to the conclusion that the surface structures of liver flukes stimulate a low B-cell immune response. The structures of the excretory-secretory system of the parasite and their products contain a lot of main antigens and induce B-immune response in man.