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1.
Ter Arkh ; 96(3): 253-259, 2024 Apr 16.
Artigo em Russo | MEDLINE | ID: mdl-38713040

RESUMO

AIM: To evaluate the impact of chronic obstructive pulmonary disease (COPD) on hospital outcomes of percutaneous coronary interventions (PCI) in patients with acute coronary syndrome (ACS). MATERIALS AND METHODS: A cohort prospective study of the COPD effect on mortality and coronary microvascular obstruction (CMVO, no-reflow) development after PCI in ACS was carried out. 626 patients admitted in 2019-2020 were included, 418 (67%) - men, 208 (33%) - women. Median age - 63 [56; 70] years. Myocardial infarction with ST elevation identified in 308 patients (49%), CMVO - in 59 (9%) patients (criteria: blood flow <3 grade according to TIMI flow grade; perfusion <2 points according to Myocardial blush grade; ST segment resolution <70%). 13 (2.1%) patients died. Based on the questionnaire "Chronic Airways Diseases, A Guide for Primary Care Physicians, 2005", 2 groups of patients were identified: 197 (31%) with COPD (≥17 points) and 429 (69%) without COPD (<17 points). Groups were compared on unbalanced data (÷2 Pearson, Fisher exact test). The propensity score was calculated, and a two-way logistic regression analysis was performed. The data were balanced by the Kernel "weighting" method, logistic regression analysis was carried out using "weighting" coefficients. Results as odds ratio (OR) and 95% confidence interval. RESULTS: The conducted research allowed us to obtain the following results, depending on the type of analysis: 1) analysis of unbalanced data in patients with COPD: OR death 3.60 (1.16-11.12); p=0.03; OR CMVO 0.65 (0.35-1.22); p=0,18; 2) two-way analysis with propensity score: OR death 3.86 (1.09-13.74); p=0.04; OR CMVO 0.61 (0.31-1.19); p=0.15; 3) regression analysis with "weight" coefficients: OR death 12.49 (2.27-68.84); p=0.004; OR CMVO 0.63 (0.30-1.33); p=0.22. CONCLUSION: The presence of COPD in patients with ACS undergoing PCI increases mortality and does not affect the incidence of CMVO.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/mortalidade , Intervenção Coronária Percutânea/métodos , Intervenção Coronária Percutânea/estatística & dados numéricos , Feminino , Síndrome Coronariana Aguda/cirurgia , Síndrome Coronariana Aguda/terapia , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Federação Russa/epidemiologia , Mortalidade Hospitalar , Resultado do Tratamento
2.
Curr Top Microbiol Immunol ; 435: 1-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-30599050

RESUMO

Chikungunya virus (CHIKV) was discovered more than six decades ago, but has remained poorly investigated. However, after a recent outbreak of CHIK fever in both hemispheres and viral adaptation to new species of mosquitoes, it has attracted a lot of attention. The currently available experimental data suggest that molecular mechanisms of CHIKV replication in vertebrate and mosquito cells are similar to those of other New and Old World alphaviruses. However, this virus exhibits a number of unique characteristics that distinguish it from the other, better studied members of the alphavirus genus. This review is an attempt to summarize the data accumulated thus far regarding the molecular mechanisms of alphavirus RNA replication and interaction with host cells. Emphasis was placed on demonstrating the distinct features of CHIKV in utilizing host factors to build replication complexes and modify the intracellular environment for efficient viral replication and inhibition of the innate immune response. The available data suggest that our knowledge about alphavirus replication contains numerous gaps that potentially hamper the development of new therapeutic means against CHIKV and other pathogenic alphaviruses.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Vírus , Animais , Vírus Chikungunya/genética , Replicação Viral
3.
Sovrem Tekhnologii Med ; 13(6): 6-13, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35265354

RESUMO

The aim of the study was to develop, evaluate, and validate an artificial neural network to predict coronary microvascular obstruction (CMVO) during percutaneous coronary interventions (PCI) in patients with myocardial infarctions (MI) based on the parameters, which are routinely available in an operating room when choosing a surgical approach. Materials and Methods: 5621 patients with MI and emergency PCI were retrospectively selected from the database of the City Clinical Hospital No.13 (Nizhny Novgorod, Russia); among them, there were 3935 men (70%) and 1686 women (30%), their mean age was 61.5±10.8 years. CMVO was recorded in 201 (4%) patients (the blood flow in the infarction-related artery after PCI was less than 3 points according to TIMI flow grade). The following input parameters were assessed: age, gender, past history of coronary artery disease, previous revascularization, presence of ST-segment elevation, a class of acute heart failure, a fact of systemic thrombolytic therapy administration and its effectiveness, symptom-to-balloon time, severity of coronary thrombosis and atherosclerosis, the number of stents and the number of operated coronary arteries. The sampling was divided into a training group (n=4060), a testing group (n=717), and an independent validation group (n=844). Results: We developed an artificial neural network by a fully connected multilayer perception with forward signal propagation and two hidden layers (the area under the ROC curve - 0.69) to predict CMVO based on the subsampling for training and testing. The network model was tested on an independent subsampling (the area under the ROC curve - 0.64, negative predictive value - 97.4%, positive predictive value - 14.6%). Conclusion: The developed artificial neural network enables to use the parameters routinely available in an operating room when choosing a surgical approach and predict CMVO development during PCI in MI patients with accuracy sufficient for practical use.


Assuntos
Infarto do Miocárdio , Fenômeno de não Refluxo , Intervenção Coronária Percutânea , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/cirurgia , Redes Neurais de Computação , Fenômeno de não Refluxo/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Estudos Retrospectivos
4.
Khirurgiia (Mosk) ; (3): 84-87, 2019.
Artigo em Russo | MEDLINE | ID: mdl-30938362

RESUMO

The experience of video-assisted thoracoscopic interventions for thymus tumors in the Research Institute of Oncology of Tomsk National Research Medical Center is presented. We also evaluate the features of postoperative management of these patients.


Assuntos
Cirurgia Torácica Vídeoassistida/métodos , Timectomia/métodos , Timoma/cirurgia , Neoplasias do Timo/cirurgia , Humanos , Cuidados Pós-Operatórios , Resultado do Tratamento
5.
Arch Virol Suppl ; (18): 139-47, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15119769

RESUMO

Alphaviruses cause chronic noncytopathic infection in mosquito cells and develop a highly cytopathic infection in a wide variety of cells of vertebrate origin. Upon infection, alphaviruses modify cellular processes to meet the virus needs for propagation. Downregulation of translation and transcription caused by viral infection appears to reduce interferon (IFN) and cytokine gene expression and allows more efficient dissemination of infection. Alphaviruses with mutations in nonstructural protein nsP2 can become less cytopathic and capable of persisting in some vertebrate cell lines for a number of passages. nsP2 likely functions as an important regulator of virus-host cell interactions and plays a significant role in suppressing the antiviral response. Mammalian cells having no defects in type I IFN system react to replication of the nsP2 viral mutants by more efficient activation of IFN and IFN-dependent genes and are capable of eliminating established alphavirus infection. Blocking of IFN-alpha/beta signaling makes mouse fibroblasts unable to stop replication of Sindbis virus (SINV) with mutated nsP2 and leads to persistent infection. Downregulation of transcription and translation during alphavirus infection are quite independent events, and both probably are involved in inhibition of the antiviral response.


Assuntos
Infecções por Alphavirus/imunologia , Infecções por Alphavirus/fisiopatologia , Alphavirus/fisiologia , Alphavirus/genética , Infecções por Alphavirus/genética , Citocinas/genética , Regulação da Expressão Gênica/imunologia , Genoma Viral , Humanos , Interferons/genética , Biossíntese de Proteínas , Replicação Viral
6.
Journal of virology ; 77(17): 9278-9286, Sep. 2003. ilus, tab, graf
Artigo em Inglês | MedCarib | ID: med-17890

RESUMO

Venezuelan equine encephalitis virus (VEEV) is an important, naturally emerging zoonotic virus. VEEV was a significant human and equine pathogen for much of the past century, and recent outbreaks in Venezuela and Colombia (1995), with about 100,000 human cases, indicate that this virus still poses a serious public health threat. The live attenuated TC-83 vaccine strain of VEEV was developed in the 1960s using a traditional approach of serial passaging in tissue culture of the virulent Trinidad donkey (TrD) strain. This vaccine presents several problems, including adverse, sometimes severe reactions in many human vaccinees. The TC-83 strain also retains residual murine virulence and is lethal for suckling mice after intracerebral (i.c.) or subcutaneous (s.c.) inoculation. To overcome these negative effects, we developed a recombinant, chimeric Sindbis/VEE virus (SIN-83) that is more highly attenuated. The genome of this virus encoded the replicative enzymes and the cis-acting RNA elements derived from Sindbis virus (SINV), one of the least human-pathogenic alphaviruses. The structural proteins were derived from VEEV TC-83. The SIN-83 virus, which contained an additional adaptive mutation in the nsP2 gene, replicated efficiently in common cell lines and did not cause detectable disease in adult or suckling mice after either i.c. or s.c. inoculation. However, SIN-83-vaccinated mice were efficiently protected against challenge with pathogenic strains of VEEV. Our findings suggest that the use of the SINV genome as a vector for expression of structural proteins derived from more pathogenic, encephalitic alphaviruses is a promising strategy for alphavirus vaccine development.


Assuntos
Animais , Masculino , Feminino , Sequência de Bases , Chlorocebus aethiops , Cricetinae , Vírus da Encefalite , RNA , Sindbis virus
7.
RNA ; 7(11): 1638-51, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11720292

RESUMO

Alphavirus genome replication is a multistep asymmetric process. Several lines of evidence suggest that the template preference of the RNA replicase is regulated by proteolytic cleavage of the viral nonstructural polyprotein. Cis-acting RNA elements in the viral genome also play crucial roles in regulating genome replication and subgenomic RNA transcription. In this report, a series of RNA templates were analyzed in vitro and in vivo to define functional elements in the 5' end of the genome. The 5' UTR was shown to contain distinct core promoter elements for both minus- and plus-strand synthesis. In addition, two conserved stem-loop structures within the nsP1 coding sequence enhanced RNA replication but were not required. Studies with chimeric templates and trans-competition experiments suggest that the 5' determinant for minus-strand initiation can differ among alphaviruses and binds to one or more limiting replicase components. The results provide compelling evidence that the 5' and 3' ends of alphavirus genome RNAs must interact to initiate replication and we propose one model for how this interaction might occur. In addition to providing new insight into the initiation of alphavirus genome replication, these results have implications for the development of improved alphavirus vector systems with reduced recombination potential.


Assuntos
Regiões 5' não Traduzidas/fisiologia , RNA Viral/fisiologia , Sequências Reguladoras de Ácido Nucleico/fisiologia , Sindbis virus/genética , Regiões 3' não Traduzidas/fisiologia , Alphavirus/genética , Animais , Sequência de Bases , Linhagem Celular , Cricetinae , Genoma Viral , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , RNA Viral/biossíntese , RNA Viral/química , Sindbis virus/fisiologia
8.
J Virol ; 75(9): 4226-38, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11287572

RESUMO

An internal ribosome entry site (IRES) mediates translation initiation of bovine viral diarrhea virus (BVDV) RNA. Studies have suggested that a portion of the N(pro) open reading frame (ORF) is required, although its exact function has not been defined. Here we show that a subgenomic (sg) BVDV RNA in which the NS3 ORF is preceded only by the 5' nontranslated region did not replicate to detectable levels following transfection. However, RNA synthesis and cytopathic effects were observed following serial passage in the presence of a noncytopathic helper virus. Five sg clones derived from the passaged virus contained an identical, silent substitution near the beginning of the NS3 coding sequence (G400U), as well as additional mutations. Four of the reconstructed mutant RNAs replicated in transfected cells, and in vitro translation showed increased levels of NS3 for the mutant RNAs compared to that of wild-type (wt) MetNS3. To more precisely dissect the role of these mutations, we constructed two sg derivatives: ad3.10, which contains only the G400U mutation, and ad3.7, with silent substitutions designed to minimize RNA secondary structure downstream of the initiator AUG. Both RNAs replicated and were translated in vitro to similar levels. Moreover, ad3.7 and ad3.10, but not wt MetNS3, formed toeprints downstream of the initiator AUG codon in an assay for detecting the binding of 40S ribosomal subunits and 43S ribosomal complexes to the IRES. These results suggest that a lack of stable RNA secondary structure(s), rather than a specific RNA sequence, immediately downstream of the initiator AUG is important for optimal translation initiation of pestivirus RNAs.


Assuntos
Vírus da Diarreia Viral Bovina/genética , Iniciação Traducional da Cadeia Peptídica , Peptídeo Hidrolases , RNA Helicases , RNA Viral/biossíntese , Replicon , Replicação Viral , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Linhagem Celular , Códon , DNA Viral , Vírus da Diarreia Viral Bovina/fisiologia , Genoma Viral , Dados de Sequência Molecular , Mutagênese , Estabilidade de RNA , Ribossomos/metabolismo , Proteínas não Estruturais Virais/genética
9.
J Virol ; 74(24): 11849-57, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11090185

RESUMO

The ability to target antigen-presenting cells with vectors encoding desired antigens holds the promise of potent prophylactic and therapeutic vaccines for infectious diseases and cancer. Toward this goal, we derived variants of the prototype alphavirus, Sindbis virus (SIN), with differential abilities to infect human dendritic cells. Cloning and sequencing of the SIN variant genomes revealed that the genetic determinant for human dendritic cell (DC) tropism mapped to a single amino acid substitution at residue 160 of the envelope glycoprotein E2. Packaging of SIN replicon vectors with the E2 glycoprotein from a DC-tropic variant conferred a similar ability to efficiently infect immature human DC, whereupon those DC were observed to undergo rapid activation and maturation. The SIN replicon particles infected skin-resident mouse DC in vivo, which subsequently migrated to the draining lymph nodes and upregulated cell surface expression of major histocompatibility complex and costimulatory molecules. Furthermore, SIN replicon particles encoding human immunodeficiency virus type 1 p55(Gag) elicited robust Gag-specific T-cell responses in vitro and in vivo, demonstrating that infected DC maintained their ability to process and present replicon-encoded antigen. Interestingly, human and mouse DC were differentially infected by selected SIN variants, suggesting differences in receptor expression between human and murine DC. Taken together, these data illustrate the tremendous potential of using a directed approach in generating alphavirus vaccine vectors that target and activate antigen-presenting cells, resulting in robust antigen-specific immune responses.


Assuntos
Proteínas E2 de Adenovirus/genética , Infecções por Alphavirus/genética , Infecções por Alphavirus/virologia , Células Dendríticas/virologia , Vetores Genéticos , Sindbis virus/genética , Substituição de Aminoácidos , Animais , Células Cultivadas , Humanos , Camundongos , Replicon , Vacinas Virais , Replicação Viral/genética
10.
J Periodontol ; 71(3): 476-81, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10776937

RESUMO

BACKGROUND: Epidemiological studies have suggested that stress can alter the onset and progression of periodontal disease. However, the mechanisms involved are not clear. The present study was designed to examine whether the functional response of mouse macrophages stimulated by Porphyromonas gingivalis lipopolysaccharide (LPS) is affected by experimental stress, and to investigate the role of corticosterone (CS) in the stress-related effects. METHODS: Two models of stress were used: emotional (isolation) and physical (cold). We measured thioglycollate-induced macrophage recruitment in vivo, and LPS-induced nitric oxide (NO) secretion by the macrophages in vitro. Two groups of mice were exposed to the stress conditions: isolation or cold. A third group was injected daily with CS, and a fourth group was used as a control (no stress). After 3 days of stress conditions, thioglycollate was injected into the peritoneal cavity. Four days later, peritoneal macrophages were isolated, counted, and cultured. The secretion of NO by the cultured cells was evaluated with and without P. gingivalis LPS stimulation. RESULTS: The number of cells in the peritoneal lavage of stressed mice was significantly reduced in comparison to macrophages isolated from non-stressed animals. The number of macrophages from CS-treated mice did not differ from controls. NO secretion from unstimulated macrophages did not differ between the stressed and control groups. Stimulation of the macrophages with P. gingivalis LPS significantly enhanced NO secretion by macrophages from the control and stressed animals, but not by the CS-treated group. NO levels secreted by P. gingivalis-stimulated cells from the two stressed groups were significantly higher than the levels secreted by controls, and the isolation group released significantly higher levels than the cold group. Stimulation of the macrophages with P. gingivalis LPS and interferon (IFN)-gamma resulted in enhanced NO secretion in the 4 groups compared to LPS alone, with no significant differences between the groups. CONCLUSIONS: The results suggest that experimental stress modulates the response of macrophages to inflammatory stimulants, and that CS is not the sole mediator involved. The presence of IFN-gamma in the culture may mask the functional differences induced by stress. The stress-induced upregulation of NO secretion might be involved in the accelerated periodontal destruction in stressed subjects.


Assuntos
Sequestradores de Radicais Livres/metabolismo , Lipopolissacarídeos/imunologia , Ativação de Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Óxido Nítrico/metabolismo , Porphyromonas gingivalis/imunologia , Estresse Fisiológico/imunologia , Análise de Variância , Animais , Anti-Inflamatórios/farmacologia , Contagem de Células , Separação Celular , Células Cultivadas , Corticosterona/farmacologia , Feminino , Sequestradores de Radicais Livres/imunologia , Interferon gama/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos , Óxido Nítrico/imunologia , Estresse Psicológico/imunologia , Tioglicolatos/farmacologia , Regulação para Cima
11.
Vopr Onkol ; 46(6): 682-5, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11219938

RESUMO

The data on such highly-effective invasive diagnostico-therapeutic procedures as ductography, sclerosing-solution cystography, X-ray-controled puncture biopsy, stereotactical computer technique, sonography and preoperative maging of nonpalpable lesions were analyzed following a complex mammographic examination of 20,000 patients with different breast pathologies. Advantages offered by complex breast examination are discussed. Among them were the use of optimal effects of each invasive procedure, an accuracy of preoperative diagnosis reaching 95-98% (nonpalpable breast lesions included) and a significantly reduced extent of breast surgery.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Radiografia Intervencionista , Adulto , Biópsia por Agulha/métodos , Doenças Mamárias/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Técnicas Estereotáxicas , Ultrassonografia
12.
J Periodontol ; 70(3): 289-93, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10225545

RESUMO

BACKGROUND: The impact of emotional stress on the outcome of infectious diseases was studied in animal models and humans, but data related to the effect of stress on periodontal infection are limited. Using the subcutaneous chamber model in mice, the present study was carried out to investigate the effect of stress on the host response to Porphyromonas gingivalis. METHODS: Mice with subcutaneous chambers (2 per animal) were divided into 4 treatment groups: cold-stress; isolation-stress; corticosterone (CS)-injected; and controls. On the third day of stress conditions, heat-killed P. gingivalis were injected into the chambers. The chambers were sampled 1 and 5 days later and analyzed for leukocyte number, tumor necrosis factor (TNF)-alpha levels, and interferon (IFN)-gamma levels. RESULTS: Injection of P. gingivalis induced the migration of leukocytes into the chambers and increased the intrachamber levels of IFN-gamma and TNF-alpha. There were no significant differences in cell number and IFN-gamma levels between the different treatment groups, but the levels of TNF-alpha were significantly lower in the isolation-stress and cold-stress groups compared to control animals. CS-injected animals were not different from controls. In addition, the levels of TNF-alpha in the stressed animals were lower on the fifth day post-injection than on the first day, but not in the CS and control group. CONCLUSIONS: The results suggest that the levels of TNF-alpha induced by P. gingivalis in the infection site are downregulated in stressed animals, and CS is not the sole mediator responsible. The stress-induced reduction in TNF-alpha levels might have an impact on the pathogenesis of periodontal disease in humans experiencing emotional stress.


Assuntos
Infecções por Bacteroidaceae/imunologia , Porphyromonas gingivalis/imunologia , Estresse Fisiológico/imunologia , Estresse Psicológico/imunologia , Animais , Anti-Inflamatórios/farmacologia , Movimento Celular/imunologia , Temperatura Baixa/efeitos adversos , Corticosterona/farmacologia , Cultura em Câmaras de Difusão , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Mediadores da Inflamação/farmacologia , Interferon gama/análise , Contagem de Leucócitos , Leucócitos/imunologia , Camundongos , Doenças Periodontais/etiologia , Doenças Periodontais/imunologia , Doenças Periodontais/microbiologia , Isolamento Social , Estresse Fisiológico/fisiopatologia , Estresse Psicológico/fisiopatologia , Fator de Necrose Tumoral alfa/análise
13.
Proc Natl Acad Sci U S A ; 96(8): 4598-603, 1999 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-10200308

RESUMO

Alphavirus vectors are being developed for possible human vaccine and gene therapy applications. We have sought to advance this field by devising DNA-based vectors and approaches for the production of recombinant vector particles. In this work, we generated a panel of alphavirus vector packaging cell lines (PCLs). These cell lines were stably transformed with expression cassettes that constitutively produced RNA transcripts encoding the Sindbis virus structural proteins under the regulation of their native subgenomic RNA promoter. As such, translation of the structural proteins was highly inducible and was detected only after synthesis of an authentic subgenomic mRNA by the vector-encoded replicase proteins. Efficient production of biologically active vector particles occurred after introduction of Sindbis virus vectors into the PCLs. In one configuration, the capsid and envelope glycoproteins were separated into distinct cassettes, resulting in vector packaging levels of 10(7) infectious units/ml, but reducing the generation of contaminating replication-competent virus below the limit of detection. Vector particle seed stocks could be amplified after low multiplicity of infection of PCLs, again without generating replication-competent virus, suggesting utility for production of large-scale vector preparations. Furthermore, both Sindbis virus-based and Semliki Forest virus-based vectors could be packaged with similar efficiency, indicating the possibility of developing a single PCL for use with multiple alphavirus-derived vectors.


Assuntos
Alphavirus/genética , Vetores Genéticos , Vírus da Floresta de Semliki/genética , Sindbis virus/genética , Vacinas Sintéticas , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/imunologia , Vacinas Virais , Animais , Formação de Anticorpos , Linhagem Celular , Transformação Celular Viral , Cricetinae , Feminino , Humanos , Rim , Camundongos , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Viral/genética , Linfócitos T Citotóxicos/imunologia , Transcrição Gênica , Proteínas Estruturais Virais/biossíntese
14.
J Virol ; 73(5): 3854-65, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10196280

RESUMO

The natural life cycle of alphaviruses, a group of plus-strand RNA viruses, involves transmission to vertebrate hosts via mosquitoes. Chronic infections are established in mosquitoes (and usually in mosquito cell cultures), but infection of susceptible vertebrate cells typically results in rapid shutoff of host mRNA translation and cell death. Using engineered Sindbis virus RNA replicons expressing puromycin acetyltransferase as a dominant selectable marker, we identified mutations allowing persistent, noncytopathic replication in BHK-21 cells. Two of these adaptive mutations involved single-amino-acid substitutions in the C-terminal portion of nsP2, the viral helicase-protease. At one of these loci, nsP2 position 726, numerous substitution mutations were created and characterized in the context of RNA replicons and infectious virus. Our results suggest a direct correlation between the level of viral RNA replication and cytopathogenicity. This work also provides a series of alphavirus replicons for noncytopathic gene expression studies (E. V. Agapov, I. Frolov, B. D. Lindenbach, B. M. Prágai, S. Schlesinger, and C. M. Rice, Proc. Natl. Acad. Sci. USA 95:12989-12994, 1998) and a general strategy for selecting RNA viral mutants adapted to different cellular environments.


Assuntos
RNA Viral/biossíntese , Replicon , Sindbis virus/genética , Replicação Viral , Adaptação Biológica , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Arilamina N-Acetiltransferase , Biomarcadores , Linhagem Celular , Embrião de Galinha , Mapeamento Cromossômico , Cricetinae , Cisteína Endopeptidases/genética , Efeito Citopatogênico Viral , Mamíferos , Dados de Sequência Molecular , Mutagênese , Fenótipo , Processamento de Proteína Pós-Traducional , Puromicina/farmacologia , RNA Viral/fisiologia , Homologia de Sequência de Aminoácidos , Sindbis virus/fisiologia , Latência Viral
15.
Vopr Onkol ; 45(1): 80-7, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10941373

RESUMO

The report deals with such present-day invasive procedures of breast examination as X-ray-controlled puncture, puncture using X-ray contrast, Cytoguide video-accessory unit controlled puncture biopsy, "pistol-needle" application, ultrasound aiming puncture, pneumocystography, ductography and preoperative interstitial marking of nonpalpable masses. If latest invasive procedures are used during complex examination of the breast, diagnostic accuracy can be raised to 95-97%.


Assuntos
Biópsia por Agulha/métodos , Doenças Mamárias/diagnóstico por imagem , Adulto , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia , Ultrassonografia , Gravação de Videoteipe
16.
Vestn Rentgenol Radiol ; (3): 26-30, 1999.
Artigo em Russo | MEDLINE | ID: mdl-12717878

RESUMO

Based on results of comprehensive examination of 20,000 females with different breast diseases in a specialized mammological room, the paper presents the most informative invasive techniques that combine diagnostic and therapeutical potentialities, such as ductography, cystography using various sclerosing solution, various types of needle biopsies under X-ray guidance, stereotactic computer devices, ultrasound study, and various labeling modes for nonpalpable formation before surgery. It shows in expedient to make a comprehensive examination under the conditions of a mammological room where the advantages of this or that invisable intervention, including those without a dosage load, are rationally, without duplicating, used depending on the diseases detected, which increases the significance of preoperative diagnosis up to 95-98%, including that of nonpalpable formations by substantially reducing the proportion of surgical interventions into the breast.


Assuntos
Doença da Mama Fibrocística , Adulto , Biópsia por Agulha , Feminino , Doença da Mama Fibrocística/diagnóstico por imagem , Doença da Mama Fibrocística/patologia , Doença da Mama Fibrocística/cirurgia , Humanos , Pessoa de Meia-Idade , Pneumorradiografia/métodos , Sucção , Tomografia Computadorizada por Raios X
17.
Methods Mol Med ; 19: 565-74, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-21374397

RESUMO

There are currently no methods for propogating hepatitis C virus (HCV) in culture useful for the analysis of viral proteins. Therefore, we have utilized Sindbis virus-based vectors to express and study HCV genes and their products.

18.
RNA ; 4(11): 1418-35, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9814762

RESUMO

Pestiviruses, such as bovine viral diarrhea virus (BVDV), share many similarities with hepatitis C virus (HCV) yet are more amenable to virologic and genetic analysis. For both BVDV and HCV, translation is initiated via an internal ribosome entry site (IRES). Besides IRES function, the viral 5' nontranslated regions (NTRs) may also contain cis-acting RNA elements important for viral replication. A series of chimeric RNAs were used to examine the function of the BVDV 5' NTR. Our results show that: (1) the HCV and the encephalomyocarditis virus (EMCV) IRES element can functionally replace that of BVDV; (2) two 5' terminal hairpins in BVDV genomic RNA are important for efficient replication; (3) replacement of the entire BVDV 5' NTR with those of HCV or EMCV leads to severely impaired replication; (4) such replacement chimeras are unstable and efficiently replicating pseudorevertants arise; (5) pseudorevertant mutations involve deletion of 5' sequences and/or acquisition of novel 5' sequences such that the 5' terminal 3-4 bases of BVDV genome RNA are restored. Besides providing new insight into functional elements in the BVDV 5' NTR, these chimeras may prove useful as pestivirus vaccines and for screening and evaluation of anti-HCV IRES antivirals.


Assuntos
Regiões 5' não Traduzidas/genética , Vírus da Diarreia Viral Bovina/genética , Hepacivirus/genética , RNA Viral/genética , Sequências Reguladoras de Ácido Nucleico , Replicação Viral , Regiões 5' não Traduzidas/química , Animais , Sequência de Bases , Bovinos , Linhagem Celular , Vírus da Encefalomiocardite/genética , Genoma Viral , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Conformação de Ácido Nucleico , Fases de Leitura Aberta , Fenótipo , Biossíntese de Proteínas , RNA Viral/química , Seleção Genética , Análise de Sequência de RNA , Deleção de Sequência , Inoculações Seriadas , Transfecção , Regiões não Traduzidas , Replicação Viral/genética
19.
Proc Natl Acad Sci U S A ; 95(22): 12989-94, 1998 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-9789028

RESUMO

Infection of vertebrate cells with alphaviruses normally leads to prodigious expression of virus-encoded genes and a dramatic inhibition of host protein synthesis. Recombinant Sindbis viruses and replicons have been useful as vectors for high level foreign gene expression, but the cytopathic effects of viral replication have limited their use to transient studies. We recently selected Sindbis replicons capable of persistent, noncytopathic growth in BHK cells and describe here a new generation of Sindbis vectors useful for long-term foreign gene expression based on such replicons. Foreign genes of interest as well as the dominant selectable marker puromycin N-acteyltransferase, which confers resistance to the drug puromycin, were expressed as subgenomic transcripts of noncytopathic replicons or defective-interfering genomes complemented in trans by a replicon. Based on these strategies, we developed vectors that can be initiated via either RNA or DNA transfection and analyzed them for their level and stability of foreign gene expression. Noncytopathic Sindbis vectors express reasonably high levels of protein in nearly every cell. These vectors should prove to be flexible tools for the rapid expression of heterologous genes under conditions in which cellular metabolism is not perturbed, and we illustrate their utility with a number of foreign proteins.


Assuntos
Vetores Genéticos , RNA Viral/genética , Sindbis virus/genética , Transcrição Gênica , Transfecção/métodos , Animais , Linhagem Celular , Clonagem Molecular , Cricetinae , RNA Polimerases Dirigidas por DNA/biossíntese , RNA Polimerases Dirigidas por DNA/genética , Eletroporação , Genes Reporter , Proteínas de Fluorescência Verde , Rim , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Plasmídeos , Proteínas Recombinantes/biossíntese , Replicon , Proteínas Virais , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
20.
Immunology ; 93(3): 323-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9640241

RESUMO

The present study was designed to test whether the functional response of mouse macrophages elicited by chronic exposure to bacteria will be different from that of cells elicited by a non-bacterial irritant. Macrophage elicitation was conducted by Porphyromonas gingivalis, a major periodontal pathogen, in comparison to a standard elicitation by thioglycollate (TG). We measured lipopolysaccharide (LPS)-induced nitric oxide (NO) and tumour necrosis factor-alpha (TNF-alpha) secretion by the elicited macrophages, and the expression of inflammatory cytokines in the whole elicited cell population. In addition, we tested the response of TG-elicited macrophages to pretreatment with P. gingivalis LPS in vitro. Mouse peritoneal macrophages were harvested 4 days after intraperitoneal injection of TG or heat-killed P. gingivalis. TG-elicited macrophages produced undetectable levels of TNF-alpha and approximately 0.5 microM of NO. The stimulation of the macrophages with LPS resulted in the secretion of NO and TNF-alpha in a dose-dependent manner. The P. gingivalis-elicited macrophages produced basal levels of approximately 5 microM NO, but TNF-alpha was not detectable. LPS stimulation of these cells further increased the secretion of NO eightfold while TNF-alpha remained undetectable. The NO secretion by P. gingivalis-elicited cells was significantly higher than that by TG-elicited cells. Examination of cytokine expression in the whole elicited cell population revealed that both P. gingivalis-elicited cells and TG-elicited cells expressed messenger RNA for interleukin-2 (IL-2), TNF-alpha and interferon-gamma (IFN-gamma), but not for IL-4. IL-6 was expressed in P. gingivalis-elicited cells only. Pretreatment of TG-elicited macrophages with P. gingivalis LPS for 24 hr prior to a second LPS challenge resulted in down-regulation of TNF-alpha secretion and up-regulation of NO secretion, a response similar to that seen in P. gingivalis-elicited peritoneal macrophages. The results suggest that the in vivo exposure of resident macrophages to P. gingivalis induces functional changes in peritoneal macrophages. These changes might be due to the effect of P. gingivalis LPS.


Assuntos
Infecções por Bacteroidaceae/imunologia , Ativação de Macrófagos , Macrófagos Peritoneais/metabolismo , Óxido Nítrico/metabolismo , Porphyromonas gingivalis , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células Cultivadas , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos , Tioglicolatos/farmacologia
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