Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 85
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Phys Rev Lett ; 132(23): 231903, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905689

RESUMO

The cross section of the process e^{+}e^{-}→π^{+}π^{-} has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on an integrated luminosity of about 88 pb^{-1}, of which 62 pb^{-1} represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed.

2.
Klin Lab Diagn ; 67(9): 530-537, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099463

RESUMO

A method has been developed for HBV DNA finding in biological material at low viral load based on nested PCR with real-time detection of three viral targets. When developing the method, blood plasma samples were used from 128 CHB patients living in the regions of the Russian Federation and countries of Central Asia and 173 hemodialysis center patients living in the North-West Federal District. Analytical sensitivity was tested using the stepwise dilution method. HBV was detected by nested PCR. According to the method developed by us, at the first stage, the HBV DNA is amplified using at the first stage oligonucleotides complementary to the greatest similarity regions of the various HBV isolates genomes flanking the entire virus genome. At the second stage, when using the amplification product of the first stage as a template, PCR was performed using three pairs of oligonucleotides and the corresponding oligonucleotide fluorescently labeled probes to three virus genome regions (Core gene, S gene and X gene), as well as one pair of primers and the corresponding probe complementary to a human HPRT gene region. The method sensitivity for DNA extraction from plasma with a 100 µl volume was 10 IU/ml. Obtaining a threshold Ct cycle for only one fluorophore may indicate the presence of HBV DNA in the sample at a load of less than 10 IU/ml, HBV detection in this case is possible with a repeated PCR study of the corresponding sample with HBV DNA extraction from an increased plasma volume (200-1000 µl). The developed method makes it possible to identify the disease in various HBV subgenotypes and can be used to diagnose CHB in the population and risk groups, including those with the HBsAg-negative form of the disease.


Assuntos
DNA Viral , Vírus da Hepatite B , Primers do DNA/genética , DNA Viral/genética , Vírus da Hepatite B/genética , Humanos , Reação em Cadeia da Polimerase/métodos , Carga Viral/genética , Carga Viral/métodos
3.
Klin Lab Diagn ; 67(2): 115-122, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35192759

RESUMO

Parvovirus infection (PVI) is widespread, characterized by airborne, bloodborne and vertical transmission routes. Parvovirus B19 (PVB19) exhibits tropism to erythropoietic cells. According to the increased likelihood principle of PVB19 infection and the severity of the consequences, immunocompromised individuals, especially those with hematological manifestations of diseases, are in increased risk group. Based on the own research results and analysis of the published data, we have proposed specific algorithms for PVI laboratory testing in individual risk groups, taking into account the peculiarities of the development and infection manifestation in each group: in HIV-infected patients, in oncohematological patients with to whom allogeneic hematopoietic stem cell transplantation (allo-HSCT) have been prescribed (blood and bone marrow recipients), as well as in patients with chronic anemia of parasitic etiology. For each group, the main clinical or laboratory marker, treatment procedure, or patient physiological parameters have been determined, based on which it was recommended to test for PVI. For HIV-infected patients, the main criterion for PVI testing is persistent anemia. For oncohematological patients, the basis for PVI testing is allo-HSCT procedure, which is planned or performed for this particular patient. For malaria patients, the patient's age was considered as major criterion, since in malaria and PVI coinfected young children can lead to a fatal outcome. The proposed PVI diagnostics algorithms usein risk groups can help to predict the severe course of underlying disease associated with PVB19 infection, and timely correct the therapy used.


Assuntos
Eritema Infeccioso , Infecções por Parvoviridae , Parvovirus B19 Humano , Algoritmos , Pré-Escolar , Eritema Infeccioso/complicações , Humanos , Laboratórios , Infecções por Parvoviridae/complicações , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/tratamento farmacológico
4.
BMC Infect Dis ; 21(1): 24, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413197

RESUMO

BACKGROUND: HIV infection is a major health problem in Russia. We aimed to assess HIV prevalence in different population groups and to compare the characteristics of 4th generation immunoassays from Abbott, Bio-Rad, Vector-Best, Diagnostic Systems, and Medical Biological Unit. METHODS: The study included 4452 individuals from the general population (GP), 391 subjects at high risk of HIV infection (HR) and 699 with potentially interfering conditions. HIV positivity was confirmed by immunoblot and by HIV RNA, seroconversion and virus diversity panels were also used. HIV avidity was employed to assess recent infections. RESULTS: The prevalence in GP was 0.40%, higher in males (0.62%) and in people aged < 40 years (0.58%). Patients attending dermo-venereal centers and drug users had a high prevalence (34.1 and 58.8%). Recent infections were diagnosed in 20% of GP and in 4.2% of HR. Assay sensitivity was 100% except for one false negative (99,54%, MBU). Specificity was 99.58-99.89% overall, but as low as 93.26% on HR (Vector-Best). Small differences on early seroconversion were recorded. Only the Abbott assay detected all samples on the viral diversity panel. CONCLUSION: HIV infection rate in the high-risk groups suggests that awareness and screening campaigns should be enhanced. Fourth generation assays are adequate but performance differences must be considered.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Adolescente , Adulto , Idoso , Cidades/estatística & dados numéricos , Usuários de Drogas/estatística & dados numéricos , Feminino , HIV-1/imunologia , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Prevalência , Federação Russa/epidemiologia , Sensibilidade e Especificidade , Adulto Jovem
5.
Bull Exp Biol Med ; 172(2): 164-168, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34855091

RESUMO

We studied the effect of bacterial wall peptidoglycan of 7 bacterial species on the competitive properties of human-associated microorganisms. Addition of peptidoglycan to the culture medium did not change the growth characteristics of the test cultures; however, an increase in the antagonism and hydrophobicity of Bifidobacterium sp. and Enterococcus sp. was observed, while the effect on enterobacteria was predominantly indifferent or inhibitory. The effect did not depend much on the source of peptidoglycan and was equally manifested on both indigenous and probiotic strains. The observed new property of peptidoglycan indicates its participation in the formation and functioning of microbiota. The obtained data on the regulation of the properties of microorganisms provide new possibilities for the correction and maintenance of host homeostasis through host-associated microbiota.


Assuntos
Antibiose/fisiologia , Parede Celular/fisiologia , Peptidoglicano/metabolismo , Bacillus subtilis/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Bifidobacterium/fisiologia , Candida/fisiologia , Parede Celular/química , Parede Celular/metabolismo , Enterobacter/fisiologia , Enterococcus faecalis/fisiologia , Escherichia coli/fisiologia , Feminino , Humanos , Lacticaseibacillus casei/fisiologia , Técnicas Microbiológicas , Peptidoglicano/análise , Staphylococcus aureus/fisiologia
6.
Klin Lab Diagn ; 66(1): 59-64, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33567175

RESUMO

A method for detecting HBV DNA in peripheral blood at low viral load using real-time PCR was developed and its significance in identifying HBsAg-negative viral hepatitis B was evaluated. When developing the method, blood plasma samples and liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Central Asia countries. We also used blood plasma samples from 96 pregnant women and 37 hemodialysis center patients living in Northwestern Federal District, 199 foreign citizens undergoing medical examination to obtain work permits at the Directorate for Migration in the Northwestern Federal District, 397 conditionally healthy people living in the Socialist Republic of Vietnam. HBV was detected by nested PCR. Analytical sensitivity was tested using the stepwise dilution method. According to the method developed by us, at the first stage, the HBV DNA is amplified using at the first stage oligonucleotides flanking the genome region 2932-3182 ... 1-1846 nt., and at the second stage two oligonucleotides pairs to the genome virus regions (gene S and gene X) and corresponding oligonucleotide fluorescently labeled probes complementary to the amplified fragments regions carrying fluorophores at the 5'-end, and non-fluorescent quenchers at the 3'-end. The channel corresponding to the FAM fluorophore detects the HBV DNA S-region amplification product, and the channel corresponding to the ROX fluorophore detects the HBV DNA X-region amplification product. The method sensitivity for DNA extraction from plasma with a 100 µl volume was 10 IU/ml. Obtaining a threshold cycle Ct for only one FAM or ROX fluorophore may indicate the HBV DNA presence in a sample at a load of less than 10 IU / ml, HBV detection in this case is possible with a repeated PCR study of the corresponding sample with HBV DNA extraction from an increased plasma volume (200-1000 µl). The developed method makes it possible to identify various HBV genovariants, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in the population, as well as in screening blood donors in order to ensure the blood transfusions safety.


Assuntos
Vírus da Hepatite B , Hepatite B , Doadores de Sangue , DNA Viral/genética , Feminino , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Humanos , Plasma , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Federação Russa , Carga Viral
7.
Bull Exp Biol Med ; 168(4): 423-426, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32146630

RESUMO

Plasma cytokine concentration in patients with Parkinson's disease and mutation in GBA gene, in patients with sporadic Parkinson's disease, and in healthy volunteers were measured by ELISA and multiplex analysis. In patients with Parkinson's disease and mutation in GBA gene, elevated plasma concentrations of IL-1ß and TNFα were revealed by ELISA in comparison with both controls and patients with sporadic form of Parkinson's disease. Multiplex analysis revealed enhanced secretion of IL-1ß, IL-2, IFNγ and reduced plasma levels of monocyte chemoattractant protein-1 (MCP-1) in patients with Parkinson's disease and mutation in GBA gene (in comparison with other groups) and increased plasma levels of IL-13 (only in comparison with the healthy volunteers). Our results support the hypothesis that the concentrations of inflammatory mediators are increased in patients with Parkinson's disease and mutation in GBA gene.


Assuntos
Glucosilceramidase/genética , Mutação , Doença de Parkinson/genética , Idoso , Estudos de Casos e Controles , Quimiocina CCL2/sangue , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica , Glucosilceramidase/sangue , Glucosilceramidase/imunologia , Humanos , Inflamação , Interferon gama/sangue , Interferon gama/genética , Interferon gama/imunologia , Interleucina-13/sangue , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-1beta/sangue , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-2/sangue , Interleucina-2/genética , Interleucina-2/imunologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/sangue , Doença de Parkinson/imunologia , Doença de Parkinson/patologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
8.
Klin Lab Diagn ; 65(9): 574-579, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-33245644

RESUMO

The possibility of modifying the algorithms for chronic viral hepatitis B laboratory diagnosis in individuals with newly diagnosed HIV infection is analyzed. Plasma samples were used from 196 patients residing in the Northwestern Federal District. Serological HBV markers were found in 79.6% of cases. However, HBsAg was detected in 5.6% of patients. Anti-HBcore IgG antibodies are found in 62.24% of cases, anti-HBe IgG antibodies in 27.55%, anti-HBs IgG antibodies in 52.55% of cases. Using a commercial kit with a 100 IU / ml sensitivity, HBV DNA was detected in 4.6% of patients, that is, 81.8% of HBsAg-positive individuals. Using the method developed by us, HBV DNA was found in 18.36% of HIV-infected individuals, including 12.75% of cases was HBsAg-negative (latent) disease form. In the examined group, HBV of genotype D prevailed (91.7%), genotype A was detected in 8.3% of cases. The distribution of subgenotypes is presented in the following ratios: D2 - 55.6%, D1 - 22.2%, D3 - 13.9%, A2 - 8.3%. Mutations were detected in the reverse transcriptase (RT) region in 91.6% of patients, in the SHB region in 83.3%, in the Core and Precore regions in 72.2% and in 27.7% of patients, respectively. Three HBV isolates (8.3%) were identified with drug resistance mutations to lamivudine, entericavir, telbivudine and tenofovir, which are amino acid substitutions in the HBV polymerase gene at positions L180M, T184A, M204V. Vaccine escape mutations were detected in 61.1% of patients. In all samples with drug resistance mutations, escape-mutants were simultaneously present. When analyzing the basal nucleus promoter, Precore and Core regions, 22.2% of patients with the double mutation A1762T / G1764A, 25% with the mutation G1896A were identified. In one person, all three substitutions were found. In the Core region, 77.7% of patients showed mutations in one of the hot spots (codons 87, 97, 112, and 130 substitution), which can play a role in immunomodulation in CHB. Analysis of the HBV genetic structure, mutations detection early in the virus in patients with HBV can help predict the clinical course and disease progression, and ART complications. To reduce the HIV HBV co-infection burden and to appointer anti-HBV therapy, it is necessary to introduce detection the occult HBV to modify the algorithm for CHB laboratory diagnosis.


Assuntos
Infecções por HIV , Hepatite B Crônica , Hepatite B , Algoritmos , DNA Viral/genética , Genótipo , Infecções por HIV/epidemiologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/epidemiologia , Humanos , Mutação , Tenofovir
9.
Klin Lab Diagn ; 65(1): 61-66, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32155009

RESUMO

The prevalence of clinically significant virus mutations in patients with chronic viral hepatitis B from the Kyrgyz Republic was analyzed. Blood plasma samples of 64 patients with verified chronic viral hepatitis B obtained from Kyrgyzstan indigenous people were used in the work. Asymmetric PCR was carried out with extended oligonucleotides and the first reaction amplification product was further used in a new PCR with one of the nested pairs overlapping primers that flanked the entire HBV genome together, followed by sequencing. Based on the phylogenetic analysis of 64 HBV isolates obtained from patients from the Kyrgyz Republic, it was shown that only the genotype D virus was present in the examined group, the HBV subgenotype D1 (68.75%) prevailed compared with the HBV subgenotype D2 (18.75%) and subgenotype D3 (12.5%). For all subgenotypes, several independent infection sources are obvious, subclusters that include isolates from Kyrgyzstan, Kazakhstan and Uzbekistan are distinguished, as well as subclusters that include isolates only from Kyrgyzstan, which are less similar to isolates previously deposited in the international database, which probably indicates an independent HBV homologous evolution in the region. Clinically significant mutations were identified in 26.5% of patients. Including 12.5% with escape mutations that prevent the virus detection and / or allow the virus to replicate despite the vaccine (122K, 128V, 133I, 134N). Another 12.5% of the isolates are characterized by mutations that are independently associated with the liver cirrhosis and hepatocellular carcinoma development, including 21, 24, 27 nucleotides deletions in the Pre-S2 region and the S11F mutation in the PreCore region. In one case, unusual 236S and 250P mutations were found in the positions described as drug resistance sites of the P region associated with the resistance development to adefovir, tenofovir, and entecavir. The hepatitis B virus genetic structure analysis, early virus mutations detection in patients with chronic hepatitis B virus can help to choose the right vaccination strategy, antiviral and immunosuppressive therapy, as well as predict the clinical course and disease progression.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Análise Mutacional de DNA , DNA Viral/genética , Genótipo , Humanos , Cazaquistão , Quirguistão , Mutação , Filogenia , Prevalência
10.
Klin Lab Diagn ; 64(10): 635-640, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31742959

RESUMO

To analyze the method for detecting HBV DNA in peripheral blood at low viral load and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of blood and liver tissue biopsy material were used from 128 patients living in the Russian Federation and the Republic of Uzbekistan without CHB and with CHB confirmed detection of circle covalently closed HBV DNA in hepatocytes. Plasma viral load was measured using the «AmpliSens® HBV-Monitor-FL¼ kit. HBV at low viral load was detected by nested PCR. Analytical sensitivity was checked by step dilution. According to our method, at the first stage, an asymmetric PCR is carried out using extended oligonucleotide primers with different melting points, complementary to the hepatitis B different genotypes genomes greatest similarity region. To increase the sensitivity, a second PCR is performed using the first reaction amplification product and internal primers. The sensitivity of the method for DNA extraction from 100 µl of plasma was 5 IU / ml, specificity 100%. Since, in spite of the HBV genotypes characteristic geographical distribution, the detection of "alien" genovariants for certain territories is becoming more frequent, we tested the method in geographically remote but active international relations with the Russian Federation regions with a high frequency of hepatotropic viruses. The developed method for detecting HBV DNA in blood plasma at low viral load based on PCR technology allows the various HBV gene variants identification and genotyping, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in a population, as well as when screening blood donors in order to ensure the blood transfusions safety.


Assuntos
DNA Viral/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/sangue , Antígenos de Superfície da Hepatite B , Humanos , Reação em Cadeia da Polimerase , Federação Russa , Carga Viral
11.
Klin Lab Diagn ; 64(9): 565-570, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31610110

RESUMO

To analyze the method HBV covalent-closed circular DNA quantitative determination in liver puncture biopsies and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Republic of Uzbekistan. For quantitative analysis of HBV covalently closed circular DNA in a biopsy material a method was developed based on real-time PCR using TaqMan probes for the target fragment and for the endogenous reference gene, based on the detecting ccc HBV DNA method of Pollicino T. et al. When quantifying ccc DNA HBV in liver tissue of 18 moderately HBV activity with HBV DNA PCR positive results patients and 16 inactive HBsAg carriers, the ccc DNA HBV content was significantly different between groups (p<0.034) and in terms 1 copy of the ß-globin gene among moderate activity HBV patients amounted to 1.71±1.32 copies/cell, and for inactive HBsAg carriers 0.15±0.14 copies/cell. In the group of patients with severe liver fibrosis and cirrhosis, the amount of ccc DNA HBV in liver tissue in patients with HBV averaged 2.5±0.4 copies/cell, in patients with HBV + D on average 0.7±0.25 copies/cell, in patients with HCV + HBV co-infection 0.45±0.07 copies/cell, in patients with a preliminary diagnosis of chronic hepatitis C hepatitis, on average 0.12±0.04 copies/cell, in patients with cryptogenic hepatitis 0.2± 0.05 copies/cell. A significant difference was shown between the group of patients with chronic hepatitis B with marked fibrosis and cirrhosis of the liver with other patients groups, except for the group of 18 moderate activity chronic hepatitis B patients. The values of Student's t-test when compared with other groups were respectively: for patients with a HCV preliminary diagnosis t=5,92 p<0,05 f = 19, patients with cryptogenic hepatitis t=5,71 p<0,05 f = 18, with «inactive HBsAg carriage¼ t=5,55 p<0,05 f = 29, with HCV + HBV co-infection t=5,05 p<0,05 f = 15 and HBV + D co-infection t=3,82 p<0,05 f = 17. The covalently closed circular DNA HBV quantitative assessment method in liver puncture biopsies allows identifying HBsAgnegative chronic viral hepatitis B forms and also reflects the virus replication activity, which, in turn, makes it possible to assume further disease progression and evaluate the antiviral therapy effectiveness.


Assuntos
DNA Circular/análise , DNA Viral/análise , Hepatite B Crônica/diagnóstico , Biópsia por Agulha , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Humanos , Fígado , Federação Russa
12.
Bull Exp Biol Med ; 164(2): 223-228, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29177905

RESUMO

We studied the relationship between diffusion transport and morphological and microstructural organization of extracellular matrix of human intervertebral disk. Specimens of the lumbar intervertebral disks without abnormalities were studied ex vivo by diffusion-weighed magnetic resonance imaging, histological and immunohistochemical methods, and electron microscopy. Distribution of the diffusion coefficient in various compartments of the intervertebral disk was studied. Significant correlations between diffusion coefficient and cell density in the nucleus pulposus, posterior aspects of annulus fibrosus, and endplate at the level of the posterior annulus fibrosus were detected for each disk. In disks with nucleus pulposus diffusion coefficient below 15×10-4 mm2/sec, collagens X and XI were detected apart from aggrecan and collagens I and II. The results supplement the concept on the relationship between the microstructure and cell composition of various compartments of the intervertebral disk and parameters of nutrient transport.


Assuntos
Anel Fibroso/metabolismo , Núcleo Pulposo/metabolismo , Adulto , Agrecanas/genética , Agrecanas/metabolismo , Anel Fibroso/anatomia & histologia , Anel Fibroso/diagnóstico por imagem , Autopsia , Transporte Biológico , Contagem de Células , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Colágeno Tipo XI/genética , Colágeno Tipo XI/metabolismo , Difusão , Imagem de Difusão por Ressonância Magnética , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Pulposo/anatomia & histologia , Núcleo Pulposo/diagnóstico por imagem
13.
Klin Med (Mosk) ; 95(2): 112-7, 2017.
Artigo em Russo | MEDLINE | ID: mdl-30303661

RESUMO

The authors overview data on the prevalence of Zika fever with reference to biological properties of the causative agent, epidemiological process, pathogenesis, and clinical symptoms of the disease. Special attention is given to the identification of the virus in pregnant women, microcephaly in the babies born by Zika-infected women, algorithm of laboratory diagnostics, and measures needed to prevent and control mosquitoes that spread viruses.


Assuntos
Transmissão de Doença Infecciosa/prevenção & controle , Microcefalia , Complicações Infecciosas na Gravidez/diagnóstico , Infecção por Zika virus , Zika virus , Algoritmos , Feminino , Humanos , Recém-Nascido , Microcefalia/epidemiologia , Microcefalia/etiologia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/virologia , Prevalência , Zika virus/imunologia , Zika virus/isolamento & purificação , Zika virus/patogenicidade , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/terapia , Infecção por Zika virus/virologia
14.
Klin Lab Diagn ; 62(3): 165-70, 2017 Mar.
Artigo em Russo | MEDLINE | ID: mdl-30620529

RESUMO

The in-hospital infections are one of the most serious problems of medicine, especially if patients have a background immunosuppression of various genesis conditioned by both disease itself and corresponding therapy. The detection of presence of infection and identification of agent and detection of its resistance are needed for choosing adequate therapy. At that, high heterogeneity of strains and multiple resistance of nosocomial infections to antibiotics and antimicrobial pharmaceuticals and standardization of antibacterial prevention and number of other causes becomes an obstacle for both determination of medicinal sensitivity of bacterium and for identification of pathogen itself in patient. One of the most complicated in antibacterial therapy pathogens causing pyo-septic diseases, are bacteria Stenotrophomonas spp., the only significant species out of them - Stenotrophomonas maltophilia has primary multiple antibiotic resistance. The significance of early identification of S.maltophilia is obvious. The application of MALDI-ToF mass-spectrometry requires shortage of of time of species identification of primary bacterial culture up to 1-2 hours including sampling preparation and analysis of obtained specters. The sequencing of 16S rRNA requires shortage of of total time od species identification of pathogen from clinical sample (blood) up to 1-12 hours, including sampling preparation ans comparison with successions presented in international data base. The given technique permits to exclude out of analysis prolonged period of obtaining a pure hemoculture of agent. The application of sequencing of 16S rRNA and MALDI-ToF mass-spectrometry as an alternative high-precision techniques shorten time of identification of bacteria, including detection of agent directly in blood of patient. Hence, occurs optimization of complex treatment and shortage of time of selection of adequate therapy that is especially important in case of oncological patients because sensitivity of cultural methods can be diminished due to preventive antibiotics' therapy.


Assuntos
Infecção Hospitalar/diagnóstico , Filogenia , RNA Ribossômico 16S/genética , Stenotrophomonas maltophilia/genética , Antibacterianos/uso terapêutico , Técnicas de Tipagem Bacteriana , Infecção Hospitalar/genética , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Manejo de Espécimes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Stenotrophomonas maltophilia/isolamento & purificação , Stenotrophomonas maltophilia/patogenicidade
15.
Sud Med Ekspert ; 60(4): 4-8, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28766519

RESUMO

The objective of the present study was the comprehensive analysis of the postmortem changes in the lumbar intervertebral disks within different periods after death. A total of seven vertebromotor segments were distinguished in the lumbosacral region of the vertebral column based on the examination of 7 corpses. All these segments were divided into three groups in accordance with the prescription of death coming as follows: up to 12 hours (group 1), between 12 and 24 hours (group 2), and between 24 and 36 hours (group 3) after death. The models of the segments thus obtained were subjected to the study by means of diffusion weighted MRI. The removed intervertebral disks were used for morphological and immunohistochemical investigations. The comparison of the diffusion coefficients (DI) revealed the significant difference between the intervertebral disks assigned to groups 1 and 2 (p<0.01). The number of the cells in the pulpal core, the vertebral end plate, and the fibrous ring in all the above groups of the intervertebral disks was significantly reduced (p<0.01). The analysis of the correlation dependence between cell density and diffusion coefficients has demonstrated the well apparent relationship between these characteristics of the intervertebral disks comprising groups 1 and 2. It is concluded that diffusion weighted MRI in the combination with the calculation of diffusion coefficients for the intervertebral disks provides a tool for diagnostics of prescription of death coming as confirmed by the results of the morphometric studies and immunohistochemical analysis.


Assuntos
Autopsia/métodos , Disco Intervertebral , Vértebras Lombares , Mudanças Depois da Morte , Adulto , Diagnóstico , Feminino , Patologia Legal/métodos , Humanos , Imuno-Histoquímica , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/metabolismo , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Fatores de Tempo
16.
Phys Rev Lett ; 117(4): 047002, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27494495

RESUMO

We describe theoretically the depairing effect of a microwave field on diffusive s-wave superconductors. The ground state of the superconductor is altered qualitatively in analogy to the depairing due to a dc current. In contrast to dc depairing, the density of states acquires, for microwaves with frequency ω_{0}, steps at multiples of the photon energy Δ±nℏω_{0} and shows an exponential-like tail in the subgap regime. We show that this ac depairing explains the measured frequency shift of a superconducting resonator with microwave power at low temperatures.

17.
Nanotechnology ; 27(47): 47LT02, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27782000

RESUMO

The topic of superconductivity in strongly disordered materials has attracted significant attention. These materials appear to be rather promising for fabrication of various nanoscale devices such as bolometers and transition edge sensors of electromagnetic radiation. The vividly debated subject of intrinsic spatial inhomogeneity responsible for the non-Bardeen-Cooper-Schrieffer relation between the superconducting gap and the pairing potential is crucial both for understanding the fundamental issues of superconductivity in highly disordered superconductors, and for the operation of corresponding nanoelectronic devices. Here we report an experimental study of the electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. The temperature dependence of the critical current follows the textbook Ginzburg-Landau prediction for the quasi-one-dimensional superconducting channel I c âˆ¼ (1-T/T c)3/2. We find that conventional models based on the the phase slip mechanism provide reasonable fits for the shape of R(T) transitions. Better agreement with R(T) data can be achieved assuming the existence of short 'weak links' with slightly reduced local critical temperature T c. Hence, one may conclude that an 'exotic' intrinsic electronic inhomogeneity either does not exist in our structures, or, if it does exist, it does not affect their resistive state properties, or does not provide any specific impact distinguishable from conventional weak links.

18.
Radiats Biol Radioecol ; 56(5): 503-506, 2016 Sep.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30703310

RESUMO

The dose-responses of micronuclei (MN) in binucleated (BN) and mononucleated (MONO) lymphocytes cultivated with cytochalasin B (CBMN-assay) were studied. Irradiation of lymphocytes was performed in vitro (donor A) at the single dose of 1 and 2 Gy of (60)Co y-rays, or in vivo, during whole-body exposure of a cancer patient (donor B) to (60)Co γ-rays each day at a single dose of 0.115 Gy up to a total dose of 1.15 Gy. The linear dose-response for MN was determined in both BN and MONO lymphocytes of donor B. It means that when CBMN assay is applied, the MN in MONO cells represent those preexisted in vivo before each exposure. On the contrary, in lymphocytes of donor A irradiated in vitro an essential elevated MN yield with an - increased dose was observed only in BN lymphocytes. A slight dose dependent elevation of MN in MONO cells seems to be due to either their division before cytochalasin was introduced in the culture medium or their insensitivity to the CB block of cytokinesis.


Assuntos
Relação Dose-Resposta à Radiação , Linfócitos/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Neoplasias/radioterapia , Adulto , Radioisótopos de Cobalto/efeitos adversos , Citocalasina B/química , Raios gama/efeitos adversos , Humanos , Masculino , Neoplasias/sangue
19.
Artigo em Russo | MEDLINE | ID: mdl-30695347

RESUMO

AIM: Evaluate prevalence of genetic variants of hepatitis B, viruses in population of various regions of Uzbekistan with hepatitis of various genesis and different severity levels of liver fibrosis and cirrhosis. MATERIALS AND METHODS: Blood plasma and liverbiopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. Genotyping based on direct sequencing of Pre-S1/Pre-S2/S HBV DNAregion was applied. RESULTS: Hepatitis B virus was detected in 32 samples ofthe 39 provided, frequency of occurrence - 82%, respectively. Phylogenetic analysis has shown, that only genotype D was detected among the examined,patients, hepatitis B virus subtype D1 predominated (84.38%) compared with D2 (3.12%) and.D3 (12.5%) subtypes. CONCLUSION: Large-scale sequencing of HBV in, Central Asia will allow to evaluate routes of transmission and time of evolutionary separation or virus isolates. Understanding the epidemiology of the infectious process is important for development of programs for prophylaxis and therapy of the infection.


Assuntos
DNA Viral , Hepatite B , Cirrose Hepática , Análise de Sequência de DNA , Proteínas Virais , Adulto , Idoso , Biomarcadores/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Feminino , Hepatite B/genética , Hepatite B/metabolismo , Hepatite B/patologia , Humanos , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Uzbequistão , Proteínas Virais/genética , Proteínas Virais/metabolismo
20.
Artigo em Russo | MEDLINE | ID: mdl-30695348

RESUMO

AIM: Evaluate significance of covalently closed circular DNA of hepatitis B virus as a marker for detection of occult viral hepatitis B in Uzbekistan population with hepatitis of various genesis. MATERIALS AND METHODS: Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. HBV covalently closed circular DNA detection was carried out according to Pollicino T et al. (2004). RESULTS: Covalently closed circu- lar DNA of hepatitis B virus was detected in 82% of samples, including in 54.5% of patients with chronic viral hepatitis C (CVHC) and in 100% of patients with hepatitis of unknown etiology. Quantitative evaluation of content of covalently closed circular DNA of hepatitis B virus in liver tissue in patients with CVHB has shown an average of 2.5 copies of HBV genome as ccc DNA per cell, in patients with CVHB + D an average of 0.7 copies/cell, in patients with co-infection by HCV and HBV - 0.5 copies/cell, in patients with CVHC an average of 0.12 copies/cell, and in patients with cryptogenic hepatitis - 0.2 copies/cell. CONCLUSION: Detection of HBV DNA is a complex problem for effective laboratory diagnostics of hepatitis. Detection of HBV ccc DNA as a marker of occult hepatitis B in patients with CVHC and patients with hepatitis of unclear etiol- ogy is an. important factor for diagnostics, selection of adequate therapy, prognosis of disease outcome and prevention of development of severe liver diseases.


Assuntos
DNA Circular/metabolismo , DNA Viral/metabolismo , Hepacivirus/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/metabolismo , Hepatite C Crônica/metabolismo , Hepatite D/metabolismo , Vírus Delta da Hepatite/metabolismo , Feminino , Hepatite B/epidemiologia , Hepatite C Crônica/epidemiologia , Hepatite D/epidemiologia , Humanos , Masculino , Prevalência , Uzbequistão/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA