[A comparative study of the role of the yadA, invA, and psaA genes in the pathogenicity of Yersinia pseudotuberculosis].

The roles of yadA, invA, and psaA genes introduced into the genetic background of the Y. pseudotuberculosis strain possessing the large p VM82 plasmid in virulence and invasion capacity were studied. Isogenic single mutants as well as double and multiple mutants of these genes were constructed and used. LD50 was used as a measure of virulence and the estimation of the ability to invade mammalian cells and the effect of infection on the weight changes of infected mice were used as additional indicators of pathogenicity. It was shown that the YadA had a major effect on the bacterial virulence when compared with the effects of PsaA and InvA. InvA appears to mediate the main pathway of the cellular invasion. YadA is responsible for the weight loss after infection of mice with sublethal doses of Y. pseudotuberculosis. The effects of YadA on virulence and of InvA on bacterial invasion were independent of the expression of the other genes studied. To our knowledge, this study showed for the first time the direct involvement of YadA in the virulence of Y. pseudotuberculosis in mice. Further pathomorphological studies are required to reveal the differences in the pathogenesis of pseudotuberculosis caused by yadA mutants or yadA+ bacteria of Y. pseudotuberculosis.

[Wild small mammals are the reservoir hosts of the Bartonella genus bacteria in the south of Moscow region].

A total of 103 blood samples collected from wild small mammals captured in the Prioksko-Terrasny Reserve on the south of Moscow region were studied to determine the bartonellae prevalence. The examined species were the yellow-necked mice Apodemus flavicollis (35 samples), the European wood mouse Apodemus uralensis (10 samples), the bank vole Clethrionomys glareolus (51 samples), the house mouse Mus musculus (3 samples), the common vole Microtus arvalis (2 samples), and the shrew Sorex araneus (2 samples). Initially, we obtained 76 bacterial Bartonella-like isolates after plating onto the surface of the solid nutrient media. 66 of them were PCR-positive at least for three of four targets, gltA, ftsZ, ribC and 16S RNA. Thus, the percentage of the infection in the studied community was 64%. Subsequent RFLP assay showed that obtained isolates belonged to the Bartonella grahamii and/or B. taylorii species. In 7 cases we found both bartonellae species in one animal. These data were confirmed by direct sequencing of four ftsZ, four ribC and two gltA amplicons. According to our data, there is no any marked host specificity for these bartonellae species. Now we have laid the bartonellae strain collection consisting of 31 isolates. To our knowledge, this is the first investigation of the bartonellae prevalence in wild small mammals performed in Russia. The comparison of our data with those obtained by European researchers and issues of coinfection by different bartonellae species and host specificity are discussed.

[Local application of low-energy aerial and argon plasma in the treatment of suppurative wounds and trophic ulcers]. / Mestnoe primenenie nizkoénergeticheskoi vozdushnoi i argonovoi plazmy v lechenii gnoinykh ran i troficheskikh iazv.

The authors describe experimental and clinical (113 patients) data demonstrating the antimicrobial, hemostatic and stimulating the regenerating processes property of the low energy plasma in local treatment of purulent and long-standing wounds and trophic ulcers.

[Morphological characteristics of lungs in embryos and fetuses in women living in regions contaminated with radionuclides after accident at the Chernobyl power plant]. / Morfologicheskaia kharakteristika legkikh émbrionov i plodov materei, prozhivaiushchikh na territorii, zagriaznennoi radionuklidami posle avarii na Chernobyl'skoi AES.

The possibility of transplacental passage of Cr-90 and Cs-137 as well as their traces appearance in descendants muscles and bones beginning from the 2nd pregnancy trimester (and this was sometimes associated with teratogenic effects) was demonstrated on the abortion material (human embryos and fetuses) from the controlled zones of the Bryansk region. Statistically significant inhibition of the bronchial branching (according to the morphometry of the lung histological section) this indicating the disturbance of the lung prenatal morphogenesis during the "pseudoglandular" developmental stage was observed in the 1st trimester of the pregnancy in the descendants of the irradiated mothers. Lung hypoplasia was observed in some cases in the 2nd and 3rd trimesters of the pregnancy. Activation of lymphoid cells in the fetal lungs and the tendency to the enhancement in them of the ectopic erythroid hemopoiesis was revealed. These processes are considered as a reflection of the compensatory adaptive cellular reaction in the descendants respiratory organs in response to the tissue hypoxia and antigenic stimuli from the organism of the pregnant woman irradiated after the Chernobyl accident.

[The characteristics of the prenatal morphogenesis of human lungs in the area of the action of the radiation factors after the accident at the Chernobyl Atomic Electric Power Station]. / Osobennosti prenatal'nogo morfogeneza legkikh cheloveka v zone deistviia radiatsionnykh faktorov posle avarii na ChAES.

The effects of irradiation at low doses on prenatal development were studied using the abortion materials from the controlled zones of Bryansk Province, Russia. A possibility of transplacental transition of some radionuclides (90Sr and 137Cs) was shown, as well as appearance of their traces in tissues of some fetuses starting from the second trimester of pregnancy. The presence of radionuclides in the muscle and bones was combined in some cases with teratogenic effects, including lung hypoplasia. Reliable delay of the bronchi branching according to the morphometry of lung histological sections was found in the offspring of irradiated mothers during the first trimester of pregnancy, thus suggesting disturbed prenatal morphogenesis of the lungs. Lung hypoplasia was sometimes noted during the second and third trimesters of pregnancy. The lymphoid cells of the lungs in fetuses were activated and a trend was found to enhanced extravascular local erythroid hemopoiesis. This is considered by the authors as compensatory-adaptive cellular reactions in the respiratory organs to tissue hypoxia and antigenic stimuli from the irradiated maternal organism.

[Pulmonary alveolar microlithiasis]. / Legochnyi al'veoliarnyi mikrolitiaz.

The paper reports a case of pulmonary alveolar microlithiasis in a 37-year-old female. The diagnosis was established clinically and roentgenologically. The cells of bronchoalveolar lavage were studied morphologically including transmission and scanning electron microscopy. Increased functional activity of alveolar macrophages (AM), a ten-fold increase of their mitotic index, numerous polynuclear AM and foreign-body cells have been revealed.

[Circadian fluctuations in the mitotic activity of the alveolar macrophages-monocytes from mouse bronchoalveolar washings]. / Sutochnye kolebaniia mitoticheskoi aktivnosti al'veoliarnykh makrofagov-monotsitov iz bronkhoal'veoliarnykh smyvov myshei.

The mitotic activity of alveolar macrophages-monocytes (AM-M) from bronchoalveolar lavages of 18 male (Balb x Black 6) mice F1 has been studied twice a day: at 8.00 a. m. (9 mice) and 8.00 p. m. (9 mice). Significant diurnal variations of AM-M proliferation were found. The mitotic index was 3.07 +/- 0.3/1000 in the morning and 1.39 +/- 0.3/1000 in the evening (p < 0.002).

[Structural-functional characteristics of Yersinia pseudotuberculosis plasmid pVM82]. / Strukturno-funktsional'naia kharakteristika plazmidy Yersinia pseudotuberculosis pVM82.

The restriction map of Yersinia pseudotuberculosis plasmid pVM82 was established using the "chromosome walking" method. According to transpositional mutagenesis, the plasmid pVM82 appeared to be conjugative and was able to be transmitted from Y. pseudotuberculosis to the E. coli K-12 cells.

[Difficulties in the diagnosis of chronic toxoplasmosis with lung involvement]. / Trudnosti diagnostiki khronicheskogo toksoplazmoza s porazheniem legkikh.

A case of chronic acquired toxoplasmosis combined with lung impairment is described. The diagnosis was made on the basis of the data obtained as a result of the use of the latest clinical and instrumental research methods and a specific serologic test. The diagnosis was verified morphologically on thin sections of the sputum. The authors provide data on the diagnostic search for approaches to the differentiation between parasitic diseases resulting in dissemination to the lungs with calcification of the foci and broncholithiasis, tuberculosis.

[Complexities in the diagnosis of Pneumocystis pneumonia]. / Slozhnosti diagnostiki pnevmotsistnoi pnevmonii.

The authors provide clinical evidence for difficulties encountered in the diagnosis of pneumocystis pneumonia. Show the role of the methods such as examination of the bronchoalveolar lavage fluid and serological blood testing aimed at detection of the liter of antibodies to Pneumocystis carinii.

[Mitotic activity of alveolar macrophages in nonspecific diffuse lung pathology]. / Mitoticheskaia aktivnost' al'veoliarnykh makrofagov pri nespetsificheskoi diffuznoi legochnoi patologii.

Endopulmonary cytograms and mitotic activity of alveolar macrophages (AM) in the bronchoalveolar lavage (BAL) from 30 patients with diffuse lung pathology have been studied. AM mitosis was found in 24 cases. Mitotic index for all the patients was 0.65% and ranged from 0.25 to 2.75%. Electron microscopy revealed the capacity of differentiated forms of AM for mitotic division. Free AM may be regarded as slowly proliferating cell population, capable of self-reproduction in lung pathology.

[Deletion of the phage lambda att80 Tn9 genome; the type of intramolecular recombination]. / Deletsii genoma faga lambda att80 Tn9; kharakter vnutrimolekuliarnoi rekombinatsii.

The intramolecular deletion-generating recombination which transforms lambda bacteriophage genomes into the plasmids (named pLS) proved to be site-specific to a certain extent. Using electron microscopy heteroduplex analysis three preferential sites for this recombination were found in seven independent pLS isolates studied. Att-sites were not registered to be involved in the formation of deletions in isolates studied. It was shown that recombination operating in our system was independent of the phage int and bacterial recA genes.

[Nature of the plasmids determining the unstable inheritance of transposon Tn9 in Escherichia coli K-12]. / Priroda plazmid, opredeliaiushchikh nestabil'noe nasledovanie transpozona Tn9 v Escherichia coli K-12.

Unstable inheritance of transposon Tn9 in the Escherichia coli strain KS7201 had been connected with its integration into a certain bacterial chromosome site (attTn9A). However, the present work shows that the transposon is situated within an unstable plasmid in this strain. A possibility of such plasmid's formation, as a result of a deletion of a part of bacteriophage lambda DNA, is shown.

[Response of pulmonary surfactant and air-blood barrier to general acute hypothermia]. / Reaktsiia surfaktantnoi sistemy i vozdushno-krovianogo bar'era legkikh na obshchuiu ostruiu gipotermiiu.

Male rats weighing 235-350 g were subjected to cooling for 4-6 hours at -20 degrees C. The lungs of the supercooled animals developed interstitial and intraalveolar edema, focal atelectases and local hemorrhages. It was shown that under overall acute hypothermia the following processes occur in the lungs: 1/local impairment of the air-blood barrier integrity due to hydropic dystrophy and degeneration of type I alveolocytes and endotheliocytes; 2/disintegration, aggregation and membrane lysis of the alveolar surfactant which underlie atelectases; 3/accumulation of the surface active material in the interstice of the interalveolar septa both because of elimination of disintegrated surfactant by type I alveolocytes and as a result of phospholipid secretion from the basal side of type II alveolocytes; 4/an increase in functional activity of type II alveolocytes and alveolar macrophages.