Isolation and characterization of a group of new Proteus bacteriophages.

Four lytic Proteus bacteriophages, PM75, PM85, PM93, and PM116, which are active against multi-drug-resistant strains of P. mirabilis, were isolated from cattle and poultry samples. According to electron microscopy data, all of the investigated phages belonged to the family Podoviridae. They all demonstrated lytic activity against sensitive strains of P. mirabilis, and three of the phages, PM85, PM93, and PM116, are potential candidates for use in antibacterial treatment. The genomes and putative proteins of bacteriophages PM85, PM93, and PM116 were similar to those of Proteus phage vB_PmiP_Pm5460 [KP890822], and the investigated phages formed a distinct clade within the genus Sp6virus, subfamily Autographivirinae. The genome sequence of phage PM75 was similar to that of a previously described Proteus phage, PM16 [KF319020], and both of them demonstrated low nucleotide sequence identity to the genomes of the other most similar phages, namely, Vibrio phage VP93, Pantoea phage LIMElight, and KP34-like bacteriophages. According to cluster analysis of the complete genome sequences and phylogenetic analysis of the proteins essential for their life cycle, phages PM75 and PM16 are distinct from other similar phages from the phiKMV supergroup and should be recognized as constituting a new genus, "Pm16virus", within the subfamily Autographivirinae.

Experimental Study of the Effects of Nanodispersed Ceria on Wound Repair.

We studied the effects of nanodispersed ceria on wound healing in vitro and in vivo. It was found that cerium dioxide stimulated wound healing, which manifested in shrinkage of burn wound area (by 1.5 times) and intensification (by 2.4 times) marginal epithelialization.

[Prevalence of nonalcoholic fatty liver disease in outpatients in Rostov-on-Don: Regional results of the DIREG-2 study]. / Rasprostranennost' nealkogol'noi zhirovoi bolezni pecheni u patsientov ambulatorno-poliklinicheskoi praktiki v Rostove-na-Donu: regional'nye rezul'taty issledovaniya DIREG-2.

AIM: to analyze and summarize the data of the DIREG-2 study of the nonalcoholic fatty liver disease (NAFLD) register in Rostov-on-Don versus those in Russia. MATERIAL AND METHODS: The prospective disease registry study encompasses an epidemiologic, observational, cross-sectional, multicenter study estimating the prevalence of NAFLD in outpatients in Rostov-on-Don. A total of 3200 patients participated in this study. The investigators were 65 outpatient physicians. Epidemiological data were obtained during two patient visits to the research centers. RESULTS: The key result obtained from this study was the significantly higher prevalence of NAFLD in Rostov-on-Don than that in the general population (40.4 and 37.3%). In addition to the higher prevalence of NAFLD, there was also a higher spread of risk factors (RFs), such as abdominal obesity, female age of 45-55 years, and hyperlipidemia. CONCLUSION: The prevalence of NAFLD in the outpatients of Rostov-on-Don was 3.1% greater than that in Russia; this might be due to the significantly higher spread of some RFs (abdominal obesity, female age of 45-55 years, hyperlipidemia). The findings are undoubtedly necessary for the elaboration of measures for the primary and secondary prevention of NAFLD in Rostov-on-Don.

[Non-invasive techniques in diagnosis of steatosis and fibrosis in nonalcoholic fatty liver disease].

UNLABELLED: Diagnosis and treatment of nonalcoholic fatty liver disease (NAFLD) is one of the most actual problems of modern hepatology. Ultrasound elastometry is alternative method to determine the density of the liver tissue. The efficiency of the method was confirmed by a large amount of data in patients with viral hepatitis. However, the diagnostic value of elastometry was not studied enough in patients with NAFLD. THE AIM OF THE RESEARCH: to study the possibility of non-invasive diagnostic methods of examination in a complex assessment of the liver in patients with NAFLD. MATERIALS AND METHODS: We studied 24 patients with signs of NAFLD and a long persistent elevation of liver enzymes. All patients underwent a needle biopsy of the liver. We conducted a comparative analysis of the results of the morphological study of the liver tissue with ultrasound elastometry, computed tomography of the liver, biochemical blood tests. RESULTS AND DISCUSSION: Among biochemical liver enzymes ALT was a marker of NAFLD which characterized the transformation of steatosis to steatohepatitis. The combined ALT and GGT increase reflected the high activity of inflammation in the liver tissue. Elastometry results were comparable to the histological features in all liver fibrosis stages, but the maximum diagnostic accuracy was observed at the late stages. The area under the ROC-curves showed the highest precision in the F2-F3 stages, the lowest value - in the F1 stage. Imprecision of the method in the early stages of fibrosis may be due to the hepatic steatosis in NAFLD and high biochemical activity with cholestasis signs. Patients with early-stage liver fibrosis diagnosed with elastometry need additional examination using other methods of noninvasive diagnostic tools.

[The integrated approach to diagnostics of metabolic syndrome in clinical practice].

Basic criteria of diagnostics and definitions of metabolic syndrome recommended by various international associations and expert groups are discussed. Permanent changes of criteria and usage of various approaches to diagnostics influence prevalence of metabolic syndrome among populations and estimation of its association with unfavorable outcomes. Some definitions of metabolic syndrome are more sensitive in detection of risk groups for cardiovascular diseases, and others in - detection of persons with high risk of type 2 diabetes mellitus. New integrated definition of metabolic syndrome which unites pathophysiological and clinical epidemiological approaches for assessment of metabolic disorders and detection of high risk groups of patients applicable for use in everyday clinical practice is presented.

[Changes of mitochondrial DNA/nuclear DNA ratio in the blood serum following X-ray irradiation of mice at various doses].

Using quantitative real-time PCR, the copy number of mitochondrial and nuclear DNA fragments in mouse blood serum was estimated at different time points following X-ray irradiation at various doses (from 0.5 to 10 Gy). The changes in the correlation between mtDNA and nuclear DNA (mtDNA/nucDNA) in blood serum reflect the degree of radiation injury depending on the dose of irradiation. Exposure to radiation at 10 Gy and massive cell death caused by this lethal dose result in a sharp decrease by an order of magnitude of the mtDNA/nucDNA ratio in the mouse serum; the value of this parameter did not recover within the next 3 days. The opposite effect was revealed when mice were exposed to irradiation at the dose of I Gy, which is not followed by massive cell death, but leads to a higher level of the mtDNA damage as compared with the nuclear DNA protected by histones. Defective mtDNA molecules enter the bloodstream, which results in an increase of the mtDNA/nucDNA ratio in serum. Under irradiation of mice at the intermediate dose of 3 Gy the two processes described above are exhibited at once. During the first hours after irradiation an apoptotic death of radiosensitive cells and release of a large number of nuclear DNA fragments in the serum are initiated, which reduces the mtDNA/nucDNA ratio. However, at later times after irradiation, starting from 5 days, an increase of the mtDNA/nucDNA ratio is observed in the serum, presumably as a result of reparation and elimination of defective mtDNA. Thus, the mtDNA/nucDNA ratio in the serum of irradiated mice reflects the degree of the radiation damage to cells and may be considered as a biological marker of radiation injury in the future.

[Study of the possibilities of contamination and transmission by the mosquitoes Culex pipiens f. molestus Fors, a pathogen of West Nile fever].

Experimental studies have demonstrated that the mosquitoes Cx. p. f. molestus fed with virus-containing suspensions, by using an artificial membrane and hygroscopic surface, are infected in 60 to 100% cases and transmit the accepted pathogen of West Nile fever (WNF) to newborn albino mice on blood sucking. The mosquitoes of this species maybe involved in the spread of the pathogen of WNF during its epidemic outbreaks.

[Non-alcoholic fatty liver disease as an atherosclerosis risk factor].

Currently, along with cardiovascular disease, changes in lipid and carbohydrate metabolism in the syndrome of insulin resistance seen pathology of the liver. The aim of our study was to determine the prognostic significance of nonalcoholic fatty liver disease (NAFLD) to assess the risk of early manifestations of atherosclerotic disease of carotid arteries. The correlation between the presence of NAFLD and signs of early atherosclerosis in the insulin resistance syndrome. The resulting ranked a number of prognostic factors influencing the degree of change in the walls of the carotid arteries, making it possible to construct estimates of individual risk of atherosclerosis development in clinically healthy patients. The clinical significance of the results is the need for more thorough examination of patients with NAFLD to assess risk factors for progression of pathology not only the liver, and cardiovascular disease.

Mitochondrial DNA transcription in mouse liver, skeletal muscle, and brain following lethal x-ray irradiation.

Using quantitative real-time PCR, the levels of mitochondrial DNA transcripts in murine tissues (skeletal muscle, liver, and brain) were determined at different time points (1, 5, and 24 h) following X-ray irradiation at the dose of 10 Gy. One hour after irradiation the levels of mitochondrial transcripts ND2, ND4, CYTB, and ATP6 dramatically decreased by 85-95% and remained at the same minimum level for 24 h in all analyzed tissues. This decrease was not associated with depletion of mtDNA as a matrix for transcription, since mtDNA copy number increased after irradiation in all tissues. The decrease in mitochondrial transcription in liver, brain, and skeletal muscle did not generally result from the damage of cell transcription apparatus, because the transcription level of nuclear housekeeping gene BETA-ACTIN remained virtually unchanged after irradiation. The mitochondrial gene transcription decreased after irradiation in the same manner as that of the nuclear gene TFB2M encoding mitochondrial transcription factor, whose regulatory role under normal conditions is well understood.

[Impact of TNF-alpha gene polymorphism, development of atherogenic dyslipidemia and risk of atherosclerosis].

In this 5-year prospective cohort study, 92 clinically healthy subjects (42 men and 50 women) were screened for G-308A polymorphism of the TNF-alpha gene. Fasting serum lipid levels and carotid intima-media thickness (IMT) were measured. Triglyceride levels in the GA+AA group were significantly (more than 3-fold) higher than in GG genotype patients. Patients in the former group had apolipoprotein index above 1 twice more frequently in the latter. The 5-year probability of atherosclerosis in GA+AA male patients was 55.9 +/- 15.4% vs. 9.1 +/- 6.1% in GG men (p < 0.001). The presence of A allele in TNFa gene was associated with a 9 times higher risk of early atherosclerosis estimated using the multivariate stepwise Cox regression model.

[Mitochondrial genetic apparatus functioning in mice spleen cells under radiation-induced apoptosis].

An important role of mitochondria in the process of programmed cell death is widely accepted now. There is a set of nuclear-encoded mitochondrial proteins involved in this process. Apart from this, a mitochondrion contains its own genetic apparatus comprising mtDNA and replication, transcription, and translation systems. However, a mechanism of mitochondria genetic information realization under apoptosis-inducing conditions has been understood poorly. Here, using the real-time PCR technique the number of mitochondrial genes and their transcripts in mouse spleen cells after whole-body X-ray irradiation at the dosage of 10 Gy has been evaluated. During 5 h after the irradiation a nuclear DNA was subjected to fragmentation, whereas mtDNA remained intact. Moreover, in the course of time after irradiation the number of mtDNA copies increased threefold. A process of mtDNA transcription was more susceptible to the irradiation: in 1 h after exposure the number of ND2, ND4 and CYTB gene transcripts were sharply decreased. In 24 and 72 h after the irradiation the amount of ND2 and ND4 transcripts was restored to the control values, while the CYTB one remained low; the number of ATP6 transcripts was compared with the control within the whole period of observation. The difference in levels of mRNAs for the genes transcribed under the control of the same promoter for mice to be grown both under normal conditions and after x-ray irradiation allows us to propose the existing a posttranscriptional mechanism which regulates expression of mitochondrial genes and provides different recovery rates for different mitochondrial transcripts at the development of apoptosis.

[Restriction endonuclease Asi256I recognizing the nucleotide sequence 5'-GATC-3'].

A strain producing a restriction endonuclease was isolated from soil samples and identified as the Arthrobacter sp. strain Ck256. The enzyme produced by this strain was termed Asi2561. The isolation procedure for this enzyme was described, and the optimal conditions for its function were determined. It was shown that the restriction endonuclease Asi256I is a true isoschizomer of MboI, it has a temperature optimum of 6 degrees C, and can be used in molecular-biological and genetic-engineering studies performed at low temperatures.

[Sharp changes in the copy number of mtDNA and its transcription in the blood cells of X-ray irradiated mice are observed, and mtDNA fragments appear in the blood serum].

Changes in the number of mitochondrial DNA (mtDNA) copies and alterations in its transcription were followed in the blood cells of mice after their exposure to X-rays; also, extracellular mtDNA fragments were registered in the blood serum of these mice. By a real time polymerase chain reaction (RT-PCR), a sharp increase in mtDNA copy number one hour after the exposure was detected in the blood cells of 1 Gy X-ray irradiated mice. This increase in mtDNA copies is considered as a result of a compensatory reaction developed in mice in response to the radiation damage in a part of mtDNA molecules. Exposure to X-ray radiation at a dose of 10 Gy resulted in an arrest of mtDNA replication in mouse blood cells within three hours after irradiation. At the same time, RT-PCR assays showed that at the same radiation dose, an increase in the number of mtRNA of the mitochondrial nd6 gene relative to mRNA of the nuclear gene gapdh occurs. This indicates that, although mtDNA is more damaged in comparison with nuclear DNA (nDNA), the process of transcription continues in the blood cell mitochondria of mice after their exposure to 10 Gy, whereas the transcription of damaged nDNA is arrested. After the irradiation of mice with 10 Gy, mtDNA fragments of 1841 bp were registered in the blood serum. Thus, in the blood cells of mice exposed to X-rays, the copy number of mtDNA and its transcription are sharply changed, and large mtDNA fragments are observed in the blood serum.

[Release of mtDNA from mitochondria and activation of its replication in tissues of irradiated mice].

A nessessary condition for normal functioning of mitochondria is the maintenance of certain numbers of intact mtDNA molecules. In the present study, we investigasted changes in the number of mtDNA copies in brain and spleen cells of mice subjected to irradiation. For the first time, we observed the irradiation-induced output of mtDNA fragments into brain and spleen cell cytosol. In the cytosol of these cells, examined in mice 5 h after 5 Gy irradiation, 1841 h.p. mtDNA fragments were detected able to persist for at 3 weeks. In addition, larger fragments of mtDNA (10,090 b.p.) were detected in the cytosol of brain cells of irradiated mice. The occurrence of mtDNA fragments in the cytosol of brain cells is accompanied with an increase in the number of mtDNA copies in the mitochondrial matrix. The induction of mtDNA replication in brain cells of irradiated animals may be considered as a compensatory reaction in response to mtDNA damage. A sharp decrease in the amount of mtDNA copies in the mitochondrial matrix of spleen cells on the first day after irradiation may be considered as apoptosis development. However, the compensatory reaction in brain cells was also noticed but in later terms.

[State of the brachial artery wall in patients with and without metabolic syndrome].

The purpose of this study was to investigate the condition of endothelium-dependent vasodilatation of the brachial artery in patients with metabolic syndrome, as well as to determine the clinical and laboratory factors associated with disordered macrovascular reactivity. The study comprised one hundred and thirty-two 35-to-50-year-old somatically healthy men. The diagnosis of metabolic syndrome was made in accordance with the WHO criteria. Insulin resistance was assessed according to the HOMA-IR index. To evaluate the interrelationships between the risk factors of atherosclerosis and the pattern of peripheral vascular reactions, the study was carried out in two groups of patients: one comprising patients with metabolic syndrome, and the control group. The increment of the brachial artery's diameter after decompression in the control group turned out reliably more pronounced as compared with that in the study group patients (averagely 11.9+/-0.44 % for the control group subjects vs. 9.0+/-0.37% for the study group patients, p=0.047). In the group of the patients with metabolic syndrome, the diameter of the brachial artery after the test with reactive hyperaemia varied in inverse proportion with the degree of insulin resistance in accordance with the HOMA index (p=0.04, r=-0.25). Also an inverse correlation was observed with the body mass index (r=-0.43, p<0.001), the duration of arterial hypertension (r=-0.29, p=0.014), and the level of triglycerides and very low density lipoproteins (r=-0.28, p=0.02).

[Increase of mitochondrial DNA copies with low level of DNA repair in tissue cells of gamma-irradiated mice].

The damage and the change in the number of mitochondrial DNA (mtDNA) copies in brain and spleen tissues of gamma-irradiated mice were studied. The changes in the number of mitochondrial DNA (mtDNA) copies were assayed by the comparative analysis of the density values of long-extension PCR products of the mtDNA fragments (16 kb) and the cluster nuclear gene of beta-globin (8.7 kb). PCRs of mtDNA fragments and the nuclear gene of beta-globin were carried out simultaneously in one test-tube within total DNA. Our results showed that in brain and in spleen cells of mice exposed to gamma-radiation an increase in copy number (polyploidization) of mtDNA with regard to the nuclear gene beta-globin took place. The induction of polyploidization of mtDNA observed in cells of gamma-irradiated animals is regarded as the development of a compensatory reaction because of the energy deficiency due to the increased ATP consumption and structural alteration of genes controlling OXPHOS. The data enabled the assumption that because of the low efficiency of repair systems in mitochondria the induction of synthesis of new mtDNA copies on intact or little affected mtDNA templates may be the major mechanism for the retention of the mitochondrial genome which is constantly damaged by the endogenous ROS and is affected by ionizing radiation and/or other exogenous factors.

[Predictive significance of insulin resistance and metabolic syndrome for assessment of the degree of endothelium disfunction and early signs of atherosclerotic lesion].

The contribution of the clinical or laboratory risk factors associated with the metabolic syndrome to the changes in peripheral vascular reactions and to the natural history of atherosclerosis has not been established until now. The aim of the work was to study interrelations between the risk factors entering the symptom complex of the metabolic syndrome, to assess their impact on endothelium-dependent vasodilatation and constrictor component of vascular reactivity as well as on the change in the thickness of the intima-media complex (TIMC) of the common carotid artery (CCA). The study accrued 122 practically normal men aged 35 to 50 years. Stepwise multiple regression analysis has established interrelations between the disorder of vasoregulating endothelium function and the intensity of atherosclerotic lesion according to the maximal value of the TIMC of the CCA, glucose concentration 120 min after glucose load, IMT, the signs of arterial hypertension. The data have been obtained that confirmed the hypothesis of the role played by endothelium dysfunction manifesting by the disturbance of vasoregulating function, as an early marker of atherosclerosis. Carbohydrate metabolism, tissue sensitivity to insulin and the presence of arterial hypertension were most significant predictive factors of the TIMC of the CCA and disorder of arterial wall function.

[Breast cancer in Chapayevsk]. / Rak molochnoi zhelezy v Chapaevske.

Numerous epidemiological surveys show the ambiguity of evaluation of stable organic chlorine compounds as a risk factor for breast cancer (BC). This is likely to be, to a certain degree, associated with the specific features of performance of epidemiological surveys. The selection of cases of BC from different areas has provided groups with different levels of exposure that as judged from the content of the above substances in the biological environments. Only few epidemiological surveys have been made in the world to assess stable organic pollutants (SOP) as risk factors of BC mainly in occupational groups. In the local areas highly polluted with dioxins, there is evidence for their role as a risk factor of BS only for women living in Sevezo. These findings are in agreement with the results of the surveys made in Chapayevsk. The analytical epidemiological study using a case-control approach has revealed the significance of biological (BC in relatives, childlessness), occupational (women's work at CVZH) and environmental (pollution, the more frequent ingestion of local pork and fish than in the control group) risk factors of BC. In the 1950-1960s, the largest Russian enterprises of chlorine chemistry worked most actively not only in Chapayevsk, but also in towns with plants of chlorine industry, such as Dzerzhinsk, Novomoskovsk, Sayansk, Usolye-Sibirskoye, and others. Ecological and epidemiological studies should be organized in these towns in order to define the value of SOP as a risk factor of BC for general populational groups.

Mitochondrial permeability transition triggers the release of mtDNA fragments.

Fragments of mitochondrial DNA are released from mitochondria upon opening of the mitochondrial permeability transition pore. Cyclosporin A, an inhibitor of pore opening, completely prevented the release of mitochondrial fragments. Induction of mitochondrial permeability transition and subsequent release of the fragments of mitochondrial DNA could be one cause of genomic instability in the cell.