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1.
Mem. Inst. Oswaldo Cruz ; 113(12): e180328, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1040588

RESUMO

BACKGROUND Human herpesvirus 2 (HHV-2) have DNA genome with a limited genetic variability and have been classified into two clades. OBJECTIVES To identify and characterise six HHV-2 isolates derived from Brazilian women. METHODS HHV-2 isolates were performed polymerase chain reaction (PCR) and sequencing of 2250 pb of the glycoprotein B (gB) coding regions. FINDINGS Four HHV-2 isolates were classified into clade B, while the remaining two, derived from HIV-1 co-infected women, showed a notable genetic divergence (> 1%). MAIN CONCLUSION The results reveal novel HHV-2 variants. The impact of these novel variants on HHV-2 pathogenesis and HIV/HHV-2 coinfection need to be investigated.


Assuntos
Humanos , Feminino , Herpes Genital/virologia , Infecções por HIV/virologia , HIV-1 , Herpesvirus Humano 2/genética , Genes Virais/genética , Filogenia , Herpes Genital/complicações , Infecções por HIV/complicações , Reação em Cadeia da Polimerase , Bertholletia , Coinfecção/virologia
2.
Rev. Soc. Bras. Med. Trop ; 50(5): 621-628, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-897017

RESUMO

Abstract INTRODUCTION: Acute gastroenteritis (AGE) is one of the most common causes of morbidity and mortality, especially among children from developing countries. Human adenovirus (HAdV) and sapovirus (SaV) are among the agents that cause AGE. The present study aimed to detect and genotype HAdV and SaV in 172 fecal samples from children with AGE, collected during a surveillance study carried out in a low-income community in Belém, Pará, between 1990 and 1992. METHODS: HAdV was detected by nested PCR, using primers Hex1deg/Hex2deg and NeHex3deg/NeHex4deg. SaV was assayed by reverse transcription PCR (RT-PCR), nested PCR, and quantitative PCR. The nucleotide sequence was determined by direct cycle sequencing. RESULTS: Overall, 43% (74/172) of samples were positive for HAdV, of which 70.3% (52/74) were sequenced and classified as belonging to five different species, mostly A and F. For SaV, positivity was 5.2% (9/172) and genotypes GI.1, GI.7, GII.1, and GV.2 were detected. CONCLUSIONS: The present results reinforce the need for further studies to obtain epidemiological data about the circulation of these viruses in Brazil, especially in the Amazon Region, where data from the early 1990's are scarce. Furthermore, the study describes for the first time the detection of SaV genotypes GI.7 and GV.2 in Brazil, showing that these types circulated in the region more than 25 years ago.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Brasil/epidemiologia , Adenovírus Humanos/isolamento & purificação , Infecções por Caliciviridae/virologia , Sapovirus/isolamento & purificação , Gastroenterite/virologia , Genótipo , Filogenia , Fatores de Tempo , Sequência de Bases , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , Distribuição por Idade , Infecções por Caliciviridae/epidemiologia , Sapovirus/genética , Técnicas de Genotipagem/métodos , Gastroenterite/enzimologia , Genes Virais
3.
Electron. j. biotechnol ; 26: 64-68, Mar. 2017. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1008953

RESUMO

Background: Chrysanthemum plants are subject to serious viral diseases. The viruses cause severe losses of the quantity and quality of chrysanthemum. The most problematic pathogen of chrysanthemum is typically considered Chrysanthemum virus B (CVB). Thus, a method for the simultaneous detection of CVB is needed. Results: We used gene-specific primers, which were derived from the coat protein gene region of the virus, for reverse transcription to obtain cDNA. Nested amplification polymerase chain reaction (PCR) was employed to detect the viral gene. This method was sensitive enough to detect the virus at up to 10-9 dilution of the cDNA. Conclusion: A highly specific and sensitive nested PCR-based assay has been described for detecting CVB. This new method is highly specific and sensitive for the detection of CVB, which is known to infect chrysanthemum plants in the fields. Further, this protocol has an advantage over traditional methods as it is more cost-effective. This assay is ideal for an early stage diagnosis of the disease.


Assuntos
Doenças das Plantas/virologia , Carlavirus/isolamento & purificação , Carlavirus/genética , Chrysanthemum/virologia , Reação em Cadeia da Polimerase em Tempo Real , Genes Virais
4.
Braz. j. microbiol ; 47(3): 731-740, July-Sept. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-788967

RESUMO

ABSTRACT Group A rotaviruses are the main causative agent of infantile gastroenteritis. The segmented nature of the viral genome allows reassortment of genome segments, which can generate genetic variants. In this study, we characterized the diversity of the VP7, VP4 (VP8*), VP6, NSP4, and NSP5 genes of the rotaviruses that circulated from 2005 to 2011 in the Triângulo Mineiro (TM) region of Brazil. Samples with genotypes G2 (sublineages IVa-1 and IVa-3), G1 (sublineage I-A), G9 (lineage III), G12 (lineages II and III), G8 (lineage II), G3 (lineage III), P[4] (sublineages IVa and IVb), P[8] (sublineages P[8]-3.6, P[8]-3.3, and P[8]-3.1), I2 (lineage VII), E2 (lineages VI, XII, and X), and H2 (lineage III) were identified. The associations found in the samples were G1, G9, or G12 with P[8]-I1-E1-H1; G2 or G8 with P[4]-I2-E2-H2; G12 with I3-E3-H6; and G3 with P[4]-I2-E3-H3 (previously unreported combination). Reassortment events in G2P[4] strains and an apparent pattern of temporal segregation within the lineages were observed. Five TM samples contained genes that exhibited high nucleotide and amino acid identities with strains of animal origin. The present study includes a period of pre- and post-introduction of rotavirus vaccination in all Brazilian territories, thereby serving as a basis for monitoring changes in the genetic constitution of rotaviruses. The results also contribute to the understanding of the diversity and evolution of rotaviruses in a global context.


Assuntos
Humanos , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Biodiversidade , Genes Virais , Filogenia , Variação Genética , Brasil/epidemiologia , Rotavirus/isolamento & purificação , Fezes/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo
5.
Arch. argent. pediatr ; 113(5): 411-418, oct. 2015. graf, tab
Artigo em Espanhol | LILACS | ID: lil-757062

RESUMO

Introducción. Existen evidencias de la asociación de determinantes sociales con la salud infantil. Objetivo. Identificar características sociodemográficas asociadas a desigualdades en la salud infantil y evaluar el efecto acumulado sobre la salud de factores de riesgo basados en estas características. Población y métodos. Evaluamos niños de 4-13 años, de Bariloche, entre junio de 2008 y mayo de 2009. Características sociodemográficas consideradas: nivel socioeconómico, educación materna, embarazo adolescente, cobertura médica, inseguridad y hábitos familiares. Valoramos la percepción parental de la salud física y socioemocional, el estado nutricional y la salud bucal en relación con dichas características y con la acumulación de factores de riesgo. Utilizamos encuesta, antropometría y examen bucal. Resultados. Participaron 180 escolares. El nivel educativo materno se asoció con la salud física, socioemocional y bucal del niño. El porcentaje de niños con piezas faltantes o caries fue 77% entre aquellos cuyas madres, como máximo, habían completado el primario, comparado con 13% entre aquellos cuyas madres habían completado estudios terciarios/universitarios. La posibilidad de percepción de salud física y socioemocional no óptima aumentó con cada factor de riesgo 1,8 y 1,4 veces, respectivamente, y la posibilidad de caries o piezas faltantes se duplicó con cada factor de riesgo adicional. El 27,3% de los escolares presentó sobrepeso y el 8,7%, obesidad, y no se encontró asociación con características sociodemográficas. Conclusiones. El bajo nivel socioeconómico familiar y educativo materno se asoció con una mayor prevalencia de resultados de salud desfavorables. Múltiples factores de riesgo tienen un efecto acumulado sobre la percepción parental de la salud física y socioemocional y la salud bucal.


Introduction. There is evidence of an association between social determinants and child health. Objective. To identify sociodemographic characteristics related to child health inequalities and to analize the cumulative effect on health of risk factors based on these characteristics. Population and Methods. We evaluated 4-13 year-old children in Bariloche between June 2008 and May 2009. The following sociodemographic characteristics were taken into account: socioeconomic level, maternal education, adolescent pregnancy, medical coverage, unsafeness, and family habits. We assessed parental perception of physical, and social and emotional health, nutritional status and oral health in relation to these characteristics and the accumulation of risk factors. We used survey, anthropometry and oral examination. Results. One hundred and eighty students participated. The level of maternal education was associated with the child's physical, social and emotional, and oral health. The percentage of children with missing teeth or cavities reached 77% among those whose mothers had, at most, completed primary school, compared to 13% among those whose mothers had completed tertiary school or university. The possibility of perceiving a non-optimal physical, and social and emotional health increased 1.8 and 1.4 times with each risk factor, respectively, and the possibility of having missing teeth or cavities was twice as much with each additional risk factor. Overweight and obesity was observed in 27.3% and 8.7% of students, respectively, and no relationship was found with sociodemographic characteristics. Conclusions. A low family socioeconomic level and a low maternal education level were associated with a higher prevalence of unfavorable health outcomes. Multiple risk factors have an cumulative effect on parental perception of physical, social and emotional, and oral health.


Assuntos
Humanos , Transformação Celular Viral/genética , Perfilação da Expressão Gênica , Transcriptoma , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Linhagem Celular Transformada , Proliferação de Células , Células Cultivadas , Citometria de Fluxo , Expressão Gênica , Genes Virais , Genótipo , /genética , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Transcrição Gênica , Latência Viral
6.
Pesqui. vet. bras ; 35(6): 536-540, June 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-766188

RESUMO

Rotaviruses are etiological agents of diarrhea both in humans and in several animal species. Data on avian Group D rotaviruses (RVD) are scarce, especially in Brazil. We detected RVD in 4 pools of intestinal contents of broilers, layer and broiler breeders out of a total of 111 pools from 8 Brazilian states, representing an occurrence of 3.6%, by a specific RVD RT-PCR targeting the VP6 gene. Phylogenetic tree confirmed that the Brazilian strains belong to group D and 3 of the sequences were identical in terms of amino acid whereas one showed 99.5% identity with the others. The sequences described in this study are similar to other sequences previously detected in Brazil, confirming the conserved nature of the VP6 protein.


Rotavírus são agentes etiológicos de diarreia tanto em humanos como em várias espécies animais. Dados sobre rotavírus do grupo D (RVD) em aves são escassos, especialmente no Brasil. Nós detectamos RVD em 4 pools de conteúdo intestinal de frango de corte, poedeiras e matrizes de um total de 111 pools originários de 8 estados brasileiros, representando uma ocorrência de 3,6% a partir de uma RT-PCR específica para RVD, tendo como alvo o gene VP6. A árvore filogenética confirmou que as amostras brasileiras pertencem ao grupo D e três das sequências obtidas foram idênticas em termos de aminoácidos enquanto uma apresentou 99,5% de identidade com as demais. As sequências aqui definidas são semelhantes a outras sequências previamente definidas no Brasil, confirmando a natureza conservada da proteína VP6.


Assuntos
Animais , Aves Domésticas/virologia , Infecções por Rotavirus/veterinária , Rotavirus/patogenicidade , Sequência de Bases , Genes Virais , Estrutura Molecular , Filogenia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
7.
Pesqui. vet. bras ; 34(8): 717-722, Aug. 2014. ilus
Artigo em Inglês | LILACS | ID: lil-723187

RESUMO

The episodes of diarrhea caused by neonatal bovine rotavirus group A (BoRVA) constitute one of the major health problems in the calf rearing worldwide. The main G (VP7) and P (VP4) genotypes of BoRVA strains involved in the etiology of diarrhea in calves are G6P[1], G10P[11], G6P[5], and G8P[1]. However, less frequently, other G and P genotypes have been described in BoRVA strains identified in diarrheic fecal samples of calves. This study describes the identification and molecular characterization of an emerging genotype (G6P[11]) in BoRVA strains involved in the etiology of a diarrhea outbreak in beef calves in a cattle herd of high production in extensive management system. The diarrhea outbreak, which showed high morbidity (60%) and lethality (7%) rates, occurred in calves (n= 384) Nelore (Bos indicus) up to 30-day-old from the State of Mato Grosso do Sul, Brazil. BoRVA was identified in 80% (16/20) of the fecal samples analyzed by polyacrylamide gel electrophoresis (PAGE) technique. In all PAGE-positive fecal samples were amplified products with 1,062-bp and 876-bp in the RT-PCR assays for VP7 (G type) and VP4 (VP8*) (P type) of BoRVA, respectively. The nucleotide sequence analysis of VP7 and VP4 genes of four wild-type BoRVA strains showed G6-III P[11]-III genotype/lineage. The G6P[11] genotype has been described in RVA strains of human and animal hosts, however, in calves this genotype was only identified in some cross-sectional studies and not as a single cause of diarrhea outbreaks in calves with high morbidity and lethality rates as described in this study...


Os episódios de diarreia neonatal ocasionados pelo rotavírus bovino grupo A (BoRVA) constituem-se em um dos principais problemas sanitários na criação de bezerros em todo o mundo. Os principais genotipos G (VP7) e P (VP4) de cepas de BoRVA envolvidos na etiologia da diarreia em bezerros são G6P[1], G10P[11], G6P[5] e G8P[1]. No entanto, com menor frequência, outros genotipos G e P têm sido descritos em cepas de BoRVA identificadas em amostras de fezes diarreicas de bezerros. Este estudo descreve a identificação e caracterização molecular de um genotipo emergente (G6P[11]) em cepas de BoRVA envolvidas na etiologia de um surto de diarreia em bezerros de um rebanho bovino de corte de alta produção em sistema de manejo extensivo. O surto, que apresentou altas taxas de morbidade (60%) e de letalidade (7%), ocorreu em bezerros (n=384) da raça Nelore (Bos indicus) com até 30 dias de idade, provenientes do estado do Mato Grosso do Sul, Brasil. O BoRVA foi identificado em 80% (16/20) das amostras fecais analisadas pela técnica de eletroforese em gel de poliacrilamida (PAGE). Em todas as amostras fecais PAGE-positivas foi possível a amplificação por RT-PCR de produtos com 1.062 pb e 876 pb referentes aos genes VP7 (G tipo) e VP4 (VP8*) (P tipo), respectivamente, de BoRVA. A análise da sequência de nucleotídeos dos genes VP7 e VP4 de quatro cepas de BoRVA demonstrou a presença do genotipo/linhagem G6-III P[11]-III. O genotipo G6P[11] tem sido descrito em cepas de RVA de hospedeiros humanos e animais. Contudo, em bezerros, este genotipo foi apenas identificado em alguns estudos transversais e não como a única causa de surtos de diarreia em bezerros com altas taxas de morbidade e...


Assuntos
Animais , Bovinos , Bovinos/virologia , Rotavirus/isolamento & purificação , Genes Virais
8.
Rev. argent. microbiol ; 43(4): 273-277, dic. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-634704

RESUMO

Equid herpesvirus 1 (EHV-1) infection has a signifcant economic impact on equine production, causing abortion, respiratory disease, neonatal death and neurological disorders. The identifcation of specifc EHV-1 genes related to virulence and pathogenicity has been the aim of several research groups. The purpose of the present study was to analyze different genomic regions of Argentinean EHV-1 strains and to determine their possible relationship with virulence or clinical signs. Twenty-fve EHV-1 Argentinean isolates recovered from different clinical cases between 1979 and 2007 and two reference strains were amplifed and sequenced. The sequence alignments were carried out using Clustal X version 1.92 and the putative amino acid sequences were deduced using Bio-Edit version 7.05. Minor changes were observed. No changes that could be involved in the different virulence in the mouse model of three EHV-1 Argentinean strains were found. No genetic variants were observed. The genomic regions analyzed are unsuitable for differentiation between abortigenic strains and those isolated from neonatal deaths.


La infección por Herpesvirus equino 1 (EHV-1) tiene un signifcativo impacto económico en la producción equina mundial al causar abortos, enfermedad respiratoria, muertes perinatales y desórdenes neurológicos. La identifcación de genes específcos relacionados con la virulencia y patogenicidad de este virus ha sido el propósito de varios grupos de investigación. En este trabajo se analizaron diferentes regiones genómicas de cepas argentinas de EHV-1 para determinar la posible relación entre la estructura genómica y la virulencia o los signos clínicos producidos. Veinticinco cepas aisladas de diferentes casos clínicos observados entre los años 1979 y 2007 y dos cepas de referencia fueron amplifcadas y secuenciadas. El alineamiento de las secuencias se realizó con el programa Clustal X versión 1.92; el programa Bio-Edit versión 7.05 permitió deducir la secuencia de aminoácidos. Solo se observaron cambios menores, no se encontraron variaciones que pudieran estar relacionadas con la diferencia de virulencia observada previamente en el modelo ratón. No se hallaron variantes genómicas. Las regiones genómicas analizadas no permitieron diferenciar cepas abortigénicas de aquellas aisladas de muertes neonatales.


Assuntos
Animais , Camundongos , Genoma Viral , Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/virologia , Sequência de Aminoácidos , Aborto Animal/epidemiologia , Aborto Animal/virologia , Argentina/epidemiologia , Sequência de Bases , DNA Viral/genética , Genes Virais , Cavalos , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Herpesvirus Equídeo 1/classificação , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 1/patogenicidade , Doenças dos Cavalos/epidemiologia , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Virulência/genética
9.
Biol. Res ; 43(4): 475-480, 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-582863

RESUMO

Human Cytomegalovirus (HCMV) is a herpesvirus associated with serious diseases in immunocompromised subjects. The region between ORF UL133 and UL151 from HCMV, named ULb' is frequently deleted in attenuated AD169 and in highly passaged laboratory strains. However, this region is conserved in low-passaged and more virulent HCMV, like the Toledo strain. The UL146 gene, which is located in the ULb' region, encodes a CXC-chemokine analogue. The diversity of UL146 gene was evaluated among fifty-six clinical isolates of HCMV from Japan. Results show that UL146 gene was successfully amplified by the polymerase chain reaction (PCR) in only 17/56 strains (30 percent), while the success rate for UL145/UL147 gene was 18/56 strains (32 percent). After DNA sequencing, the 35 amplified strains were classified into 8 groups. When compared, variability of UL146 ranged from 25.1 percent to 52.9 percent at the DNA level and from 34.5 percent to 67 percent at the amino acid level. Seven groups had the interleukin-8 (IL-8) motif ERL (Glu-Leu-Arg) CXC and one group had only the CXC motif, suggesting the absence of the IL-8 function of UL146. In conclusion, we found that UL146 gene of HCMV is hyper-variable in clinical strains from Japan suggesting the possibility of a different function in each sequence group.


Assuntos
Humanos , Quimiocinas CXC/genética , Infecções por Citomegalovirus/virologia , Citomegalovirus/genética , Genes Virais/genética , Variação Genética/genética , Proteínas Virais/genética , Sequência de Bases , Citomegalovirus/isolamento & purificação , Fibroblastos/virologia , Genótipo , Japão , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Mem. Inst. Oswaldo Cruz ; 104(4): 599-603, July 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-523726

RESUMO

Group B streptococci (GBS) infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.


Assuntos
Humanos , Antibacterianos/farmacologia , DNA Viral/análise , Genes Virais/genética , Streptococcus agalactiae , Brasil , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Eletroforese em Gel de Campo Pulsado , Variação Genética , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidade , Virulência/genética
12.
Rev. biol. trop ; 55(2): 365-372, jun. 2007. ilus
Artigo em Inglês | LILACS | ID: lil-637587

RESUMO

Phylogenetic analysis of the envelope gene sequence (E) of three isolated Dengue virus type 1 (DEN1) sequences from the Costa Rican 1993 epidemic was performed. All the strains fell into genotype V. Genotype V has grouped all the strains isolated from America, three strains from Africa and two strains from Asia. Costa Rican strains are closely related to the strain from Angola and to the Brazil 1990 strain. Costa Rican strains are able to cause DHF but with low clinical disease severity and low incidence maybe because of low virulence. Rev. Biol. Trop. 55 (2): 365-372. Epub 2007 Jun 29.


Tres aislamientos del gen de la envoltura (E) de Dengue tipo 1 del período epidémico de 1993 en Costa Rica se analizaron filogenéticamente. Todas las cepas pertenecen al genotipo V. El genotipo V ha agrupado todos los aislamientos de América, tres cepas de África y dos cepas de Asia. Los aislamientos costarricenses están cercanamente relacionados a la cepa de Angola y al aislamiento brasileño de 1990. Las cepas costarricenses son capaces de causar Fiebre de Dengue Hemorrágico pero con baja severidad clínica y baja incidencia quizá debido a una baja virulencia.


Assuntos
Humanos , Vírus da Dengue/genética , Dengue/virologia , Filogenia , Proteínas do Envelope Viral/genética , Costa Rica/epidemiologia , Surtos de Doenças , Vírus da Dengue/classificação , Dengue/epidemiologia , Genótipo , Genes Virais/genética
13.
Rev. argent. dermatol ; 86(2): 114-118, abr.-jun. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-412755

RESUMO

La epidermodisplasia verruciforme de Lewandowsky-Lutz (EV) es una enfermedad con elevada sensibilidad a la infección por el virus del papiloma humano (HPV), indicando una falla en la respuesta inmune frente a esta virus. Se considera que la persistencia de la infección por HPVs/EV se debe a defectos inmunogenéticos. Estos incluyen variaciones del perfil de algunas citoquinas (IL-10, FNT-a, IL-1 e IL-6) y alteraciones en los niveles de CD3+ y CD8+ y en la relación entre CD4/CD8. La transformación maligna puede estar asociada con HPVs oncogénicos o con fallas en la IMC


Assuntos
Cromossomos , Epidermodisplasia Verruciforme , Genes Virais , Psoríase
14.
Braz. j. med. biol. res ; 38(1): 1-4, Jan. 2005. tab, graf
Artigo em Inglês | LILACS | ID: lil-405547

RESUMO

The present study on molecular characterization of a human papillomavirus (HPV) isolated in Central Brazil describes the L1 gene sequence from a new variant of HPV-58, the isolate Bsb-02. The sample was from a smear obtained from a woman with cervical intraepithelial neoplasia grade II. The whole L1 gene from isolate Bsb-02 was sequenced automatically, showing 99.1 percent nucleotide identity with the gene from the HPV-58 reference. The clustering between Bsb-02 and HPV-58 reference sequence was also supported by phylogenetic analysis. Fourteen nucleotide substitutions were observed: eight were synonymous and six were associated with amino acid substitutions. A10V and V144I have not been previously described. At GenBank, the only complete L1 sequence from HPV-58 in addition to the HPV-58 reference one is that of Bsb-02. These data provide information that may be relevant to HPV diagnosis and to rational vaccine strategies. HPV variants may also be associated with host immune responses and with the risk of cervical neoplasia.


Assuntos
Humanos , Feminino , Displasia do Colo do Útero/virologia , Proteínas Oncogênicas Virais/genética , Papillomaviridae , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero , Sequência de Aminoácidos , Variação Genética , Genes Virais/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Homologia de Sequência do Ácido Nucleico
15.
Rev. Inst. Med. Trop. Säo Paulo ; 46(6): 315-322, Nov.-Dec. 2004. ilus, mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-391587

RESUMO

A partir de outubro de 2001, o Instituto Adolfo Lutz tem recebido amostras de líquido vesicular e crostas de lesões de pele de pacientes das regiões do Vale do Paraíba, Estado de São Paulo e do Vale do São Patricio, Estado de Goiás. Os dados clínicos e epidemiológicos sugeriam que os surtos poderiam ser causados por Cowpox virus ou Vaccinia virus. A maioria dos pacientes era ordenhadores que tinham lesões vesicopustulares nas mãos, braços, antebraços e alguns na face. A análise por microscopia eletrônica direta (MED) detectou partículas com morfologia de vírus do gênero Orthopoxvirus em amostras de 49 (66,21%) pacientes dos 74 analisados. Os vírus foram isolados em membrana corioalantóide (MCA) de ovo embrionado de galinha e em linhagem celular Vero com confirmação por MED e PCR. Das 21 amostras de lesões submetidas ao PCR utilizando iniciadores para o gene da hemaglutinina (HA), 19 foram positivas. A digestão por enzima de restrição TaqI resultou em quatro fragmentos característicos de Vaccinia virus. A análise nucleotídica do seqüenciamento revelou que esses vírus apresentam 99,9% de similaridade com o Cantagalo virus, descrito como uma cepa de Vaccinia virus, havendo apenas alteração de um nucleotídeo na posição 616 com mudança de um aminoácido na proteína na posição 206. A análise filogenética mostrou que os isolados se agruparam junto aos Cantagalo virus, outras cepas de Vaccinia virus e Rabbitpox virus.


Assuntos
Humanos , Animais , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Embrião de Galinha , Surtos de Doenças , Vaccinia , Vírus Vaccinia , Distribuição por Idade , Sequência de Bases , Brasil , Chlorocebus aethiops , Genes Virais , Microscopia Eletrônica , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Vírus Vaccinia , Células Vero
16.
Mem. Inst. Oswaldo Cruz ; 97(4): 547-552, June 2002. ilus, graf
Artigo em Inglês | LILACS | ID: lil-314520

RESUMO

Treatment of cancer using gene therapy is based on adding a property to the cell leading to its elimination. One possibility is the use of suicide genes that code for enzymes that transform a pro-drug into a cytotoxic product. The most extensively used is the herpes simplex virus thymidine kinase (TK) gene, followed by administration of the antiviral drug ganciclovir (GCV). The choice of the promoter to drive the transcription of a transgene is one of the determinants of a given transfer vector usefulness, as different promoters show different efficiencies depending on the target cell type. In the experiments presented here, we report the construction of a recombinant adenovirus carrying TK gene (Ad-TK) driven by three strong promoters (P CMV IE, SV40 and EN1) and its effectiveness in two cell types. Human HeLa and mouse CCR2 tumor cells were transduced with Ad-TK and efficiently killed after addition of GCV. We could detect two sizes of transcripts of TK gene, one derived from the close together P CMV IE/SV40 promoters and the other from the 1.5 Kb downstream EN1 promoter. The relative amounts of these transcripts were different in each cell type thus indicating a higher flexibility of this system


Assuntos
Humanos , Animais , Camundongos , Adenoviridae , Antivirais , Ganciclovir , Terapia Genética , Timidina Quinase , Genes Virais , Vetores Genéticos , Células HeLa , Regiões Promotoras Genéticas , Células Tumorais Cultivadas
17.
Rev. invest. clín ; 54(3): 231-242, mayo-jun. 2002.
Artigo em Espanhol | LILACS | ID: lil-332922

RESUMO

Activator protein-1 (AP1) is a dimeric protein, consisting either of homodimers between c-Jun, JunB, and JunD of by heterodimers with members of the Fos-family by physically interacting via a "leucine zipper" region. AP1 is an important transcription factor initially identified as a DNA binding protein that bound to enhancer sequences of the human metallothionein IIA gene. The protein components of AP1 are encoded by a set of genes known as "immediate-early" genes that can be activated by a variety of growth factors and mitogens through several different signaling pathways. Until recently, AP1 was considered a transcription factor expressed in most tissues to regulate cellular and viral genes now, it is becoming evident that AP1 can be involved in tissue-specific regulation of target genes due to the differential combination of the components of this important transcription factor. AP1 plays a crucial role during human papillomavirus (HPV) early gene expression, in particular of the expression of E6 and E7 oncoproteins. The HPV are a group of DNA viruses consisting of more than 80 different genotypes. Some of these HPV, know as high risk HPV, are important etiologic agents of uterine-cervical cancer (CaCu). Of the different types of cancer, CaCu is one of the most frequent among women worldwide, constituting the second death cause due to neoplasia. During cellular transformation, HPV infect basal cells in stratified epithelium; their DNA integrate into the host genome usually through the E2 gene; as these cells differentiate and migrate into the upper layer of the epithelium, viral oncogene are expressed blocking their differentiation. Mutagenesis in AP1 sites belonging to the HPV promoter region (LCR) completely abolished the HPV promoter activity in different cell lines; these results and biochemistry assays on this AP1 transcription factor, that includes protein-protein interactions between AP1 and another factors as E7 from HPV, and YY-1; the post-translattional modification and, the retinoic acid interaction; suggest a role for this AP1 factor in tissue-specific transcription of the human papillomavirus.


Assuntos
Humanos , Feminino , Papillomaviridae , Genes Precoces , Genes Virais , Fator de Transcrição AP-1/fisiologia , Proteínas Imediatamente Precoces/biossíntese , Proteínas Oncogênicas Virais/genética , Papillomaviridae , Neoplasias Uterinas , Neoplasias do Colo do Útero , Regiões Promotoras Genéticas , Células Epiteliais/virologia , Especificidade de Órgãos , Fosforilação , Infecções por Papillomavirus/virologia , Infecções Tumorais por Vírus/virologia , Modelos Biológicos , Mutagênese , Processamento de Proteína Pós-Traducional , Proteínas Oncogênicas Virais/biossíntese , Proteínas Quinases/metabolismo , Regulação Viral da Expressão Gênica , Replicação Viral , Transcrição Gênica
19.
Rev. cuba. med. trop ; 49(3): 186-95, 1997. tab, graf
Artigo em Espanhol | LILACS | ID: lil-228084

RESUMO

Durante la neuropatía epidémica ocurrida en Cuba en los años 1992 y 1993, se obtuvieron del líquido cefalorraquídeo de pacientes aislamientos virales relacionados antigénicamente con los virus Coxsackie. Conjuntamente con las investigaciones virológicas se efectuaron otras de tipo epidemiológicas, toxicológicas, nutricionales, inmunológicas e histopatológicas. A pesar que la enfermedad estuvo unida a factores tóxicos-nutricionales, no ha sido posible identificar la causa de la epidemia. Teniendo en consideración los resultados obtenidos en las distintas investigaciones, hemos formulado una hipótesis integral, multifactorial, para explicar el mecanismo fisiopatológico de la participación de los virus aislados como mediadores de un proceso de autoinmunidad en la patogenia de la enfermedad


Assuntos
Antígenos Virais , Enterovirus/genética , Enterovirus/imunologia , Enterovirus/isolamento & purificação , Sistema Imunitário , Neurite (Inflamação)/etiologia , Neurite (Inflamação)/fisiopatologia , Neurite (Inflamação)/virologia , RNA Viral , Proteínas Virais , Cuba , Enterovirus/genética , Enterovirus/imunologia , Enterovirus/isolamento & purificação , Genes Virais
20.
Salud pública Méx ; 37(3): 240-247, mayo-jun. 1995. ilus
Artigo em Espanhol | LILACS | ID: lil-167365

RESUMO

Los papilomavirus humano (PVH) infectan epitelios estratificados queratinizados con una alta especificidad y están asociados con la aparición y persistencia de neoplasias benignas y malignas. Los elementos que dirigen la expresión genética de estos virus se localizan en una región no codificadora conocida como región larga de control (RLC). Al inicio del ciclo viral, una combinación particular de factores celulares que interactúan con la RLC promueven la transcripción temprana de los oncogenes virales E6 y E7. Estos favorecen la división celular interrumpiendo los mecanismos regulatorios celulares: E6 se une a la proteína supresora de tumor p35 y E7 se une a p105RB. La continuidad en la transcripción temprana conlleva al aumento gradual de las proteínas virales E1 y E2. La proteína E2 impide la transcripción temprana y confiere especificidad de unión a E1, la cual promueve la replicación viral. El cese paulatino de la transcripción de los oncogenes virales a través de la represión por E2, libre la regulación del crecimiento celular mediada por p53 y p105RB, permitiendo que la diferenciación celular progrese. Es entonces cuando el promotor tardío funciona para la producción de las proteínas de la cápside viral L1 y L2, permitiendo la maduración de viriones en los estratos superiores del epitelio. La disrupción del gen E2 durante un evento de integración del genoma viral, impide la progreción del ciclo vira y la entrada del programa de diferenciación de la célula epitelial, sosteniendo el estado transformado producido por E6 y E7


Human papillomavirus (HPV) specifically infect stratified epithelial cells, causing benign and malignant neoplasia. Several elements directing this virus' genetic expression are present in a non-coding region called LCR. HPV infection starts in the basal cells of stratified epithelia, where a particular combination of cellular factors interacting with the LCR starts the transcription of the viral E6 and E7 oncogenes. The E6 and E7 genes alter the cell cycle because they interact and inactivate tumor suppressor proteins: E6 binds and degrades protein p53 and E7 associates with p105RB. E1 and E2 are the next synthesized proteins. E2 blocks the early transcription and permits E1 specific binding to the viral origin of replication located within the lcr, initiating the viral genome replication. Following the course of viral infection, the E2-induced E6 and E7 down-regulation releases p53 and p105RB proteins, and the differentiation process can continue. Then, a putative late promoter can activate the capsid genes L1 and L2. At this step, mature virions can be detected in the upper layers of the epithelium. Disruption in E2 gene transcription is usually associated to genital malignant neoplasia. In the absence of E2, E6 and E7 remain constitutively expressed, sustaining the immortality of the infected cell and blocking the epithelial differentiation program.


Assuntos
Humanos , Masculino , Feminino , Oncogenes/genética , Papillomaviridae/genética , Condiloma Acuminado/genética , Regulação para Baixo , Genes Virais/genética , Neoplasias dos Genitais Femininos/etiologia , Neoplasias dos Genitais Masculinos/etiologia , Regulação Viral da Expressão Gênica , Transcrição Gênica/genética
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