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Objective: Torque Teno virus (TTV) is a recently discovered virus with high prevalence worldwide, that has been associated with vascular diseases. The aim of this study is to investigate the prevalence of TTV molecular DNA in the intracranial aneurysm (IA) artery walls. Method: Samples of IA walls were collected after microsurgical clipping from 35 patients with IA (22 ruptured/13 unruptured cases). The samples were submitted to molecular DNA extraction using the EasyMag automatized extractor and performed with Qiagen DNA extraction Minikit 250. The samples underwent PCR examination with primers for ß-globin as internal control using the Nanodrop ® 2000 spectrophotometer. A quantitative (real-time) PCR with TTV-specific primers was performed. Clinical and radiological data of patients included was collected. Results: TTV was detected in 15 (42.85%) cases, being 10 (45.4%) ruptured and 5 (38.4%) unruptured (p = 0.732) lesions. Multiple IAs accounted for 14 (40%) cases. Five cases (17.2%) had TTV+ and multiple aneurysms (p = 0.73). Association between presence of virus and aneurysm rupture was not statistically significant (p = 0.96). Conclusion: This study demonstrated a relatively high prevalence of viral DNA in the walls of IAs. This is the first study to identify the presence of TTV DNA in IA's samples, which was found more often in ruptured lesions. This is an exploratory study, therefore, larger studies are required to clarify the relationships between inflammation, viral infection, IA formation and rupture.
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The phage-inducible chromosomal islands (PICIs) of Gram-negative bacteria are analogous to defective prophages that have lost the ability to propagate without the aid of a helper phage. PICIs have acquired genes that alter the genetic repertoire of the bacterial host, including supplying virulence factors. Recent work by the Penadés laboratory elucidates how a helper phage infection or prophage induction induces the island to excise from the bacterial chromosome, replicate, and become packaged into functional virions. PICIs lack a complete set of morphogenetic genes needed to construct mature virus particles. Rather, PICIs hijack virion assembly functions from an induced prophage acting as a helper phage. The hijacking strategy includes preventing the helper phage from packaging its own DNA while enabling PICI DNA packaging. In the case of recently described Gram-negative PICIs, the PICI changes the specificity of DNA packaging. This is achieved by an island-encoded protein (Rpp) that binds to the phage protein (TerS), which normally selects phage DNA for packaging from a DNA pool that includes the helper phage and host DNAs. The Rpp-TerS interaction prevents phage DNA packaging while sponsoring PICI DNA packaging. Our communication reviews published data about the hijacking mechanism and its implications for phage DNA packaging. We propose that the Rpp-TerS complex binds to a site in the island DNA that is positioned analogous to that of the phage DNA but has a completely different sequence. The critical role of TerS in the Rpp-TerS complex is to escort TerL to the PICI cosN, ensuring appropriate DNA cutting and packaging.
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Bacteriófagos , Ilhas Genômicas , Bacteriófago lambda/genética , Bacteriófagos/genética , Empacotamento do DNA , DNA Viral/genética , DNA Viral/metabolismo , Endodesoxirribonucleases/genéticaRESUMO
Leprosy patients may present with immune system impairment and have a higher hepatitis B virus (HBV) seroprevalence, justifying the investigation of occult HBV infection in these individuals. The aim of this study was to verify the frequency and the clinical factors associated with occult HBV infection in leprosy patients. Between 2015 and 2016, leprosy patients from a reference center in Brazil were interviewed to assess clinical data. Blood samples were collected for the screening of HBV serological markers using enzyme-linked immunosorbent assay. Patients with negative hepatitis B surface antigen (HBsAg) that had positive anti-HBc and/or anti-HBs were selected for HBV DNA detection using real-time polymerase chain reaction. SPSS was used for data analysis. Among 114 selected patients, six were identified with occult infection (5.3%) and five of them with multibacillary leprosy. Three patients with occult infection had a history of a type 2 reaction (P = 0.072; OR, 4.97; 95% CI, 0.87-28.52). Only two patients with occult infection had isolated anti-HBc, while three had isolated anti-HBs, including those with the highest HBV DNA titers. In conclusion, in leprosy patients with negative HBsAg and positive anti-HBc and/or anti-HBs, occult HBV infection occurs in 5.3% and can be found even in patients with isolated anti-HBs.
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Hepatite B/epidemiologia , Hanseníase/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Estudos Transversais , DNA Viral/sangue , Feminino , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral , Adulto JovemRESUMO
ABSTRACT Objective: To evaluate the usefulness of a device for collecting and preserving human papilloma virus (HPV) DNA in self-collected vaginal samples stored dry during 14 days. Materials and methods: Diagnostic concordance pilot study that included non-pregnant women over 25 years of age with a biopsy-confirmed result of cervical intraepithelial neoplasia (CIN) grade 1 or more, coming to two referral centres in Bogotá, Colombia. Women with a history of total hysterectomy were excluded. Convenience sampling was used. The device uses real-time PCR (polymerase chain reaction) for DNA detection. Sociodemographic and clinical variables were measured, as well as the results of the test when the sample was collected by the patient and when it was collected by the physician, and the amount of DNA in the samples taken and processed on day 1, and in those processed on day 14, using Ct thresholds. Descriptive statistics were applied. Overall concordance was estimated by means of the kappa coefficient and mean differences in DNA amount. Materials and methods: Diagnostic concordance pilot study that included non-pregnant women over 25 years of age with a biopsy-confirmed result of cervical intraepithelial neoplasia (CIN) grade 1 or more, coming to two referral centres in Bogotá, Colombia. Women with a history of total hysterectomy were excluded. Convenience sampling was used. The device uses real-time PCR (polymerase chain reaction) for DNA detection. Sociodemographic and clinical variables were measured, as well as the results of the test when the sample was collected by the patient and when it was collected by the physician, and the amount of DNA in the samples taken and processed on day 1, and in those processed on day 14, using Ct thresholds. Descriptive statistics were applied. Overall concordance was estimated by means of the kappa coefficient and mean differences in DNA amount. Results: A kappa coefficient of 0.84 (95% CI: 0.71-0.96) was found for concordance in high-risk HPV detection between the self-collected cervicovaginal sample and the sample taken by the clinician. There were no differences in terms of the amount of viral DNA between day 1 and day 14 (DM -0.34 cycles; 95% CI: - 2.29 to 1.61). Conclusion: Self-collected vaginal samples using the storage device are reliable for high-risk HPV detection in patients with cervical dysplasia, and preserve viral DNA for 14 days if stored dry at room temperature. Confirmation studies in the general population are required.
RESUMEN Objetivo: Evaluar la utilidad de un dispositivo para toma y preservación del DNA del virus del papiloma humano (VPH) de muestras vaginales recolectadas por autotoma y almacenadas en seco durante 14 días. Materiales y métodos: Estudio piloto de concordancia diagnóstica. Se incluyeron mujeres mayores de 24 años no gestantes con un resultado de neoplasia intraepitelial cervical (NIC) grado 1 o más, confirmado por biopsia en dos instituciones de referencia en Bogotá, Colombia. Se excluyeron mujeres con antecedente de histerectomía total. Se realizó un muestreo por conveniencia. El dispositivo utiliza PCR (reacción en cadena de la polimerasa) en tiempo real para detección del ADN. Se midieron variables sociodemográficas y clínicas, así como el resultado de la prueba por autotoma y tomada por el médico, y la cantidad de ADN de las muestras tomadas el día 1 procesadas ese día, y el día 14, por medio del Ct umbral. Se realizó estadística descriptiva. Se calculó la concordancia global por medio del índice de kappa ponderado y la diferencia de medias de la cantidad de ADN. Resultados: La concordancia en la detección de VPH de alto riesgo mostró un kappa = 0,84 (IC 95 %: 0,71-0,96) entre la muestra cervicovaginal recolectada por autotoma frente a la muestra cervical recolectada por el médico. No hubo diferencias en la cantidad de ADN viral entre el día 1 y el 14 (DM -0,34 ciclos; IC 95 %: -2,29 a 1,61). Conclusión: Las muestras vaginales recolectadas por autotoma usando el dispositivo de almacenamiento son confiables para la detección de VPH de alto riesgo en pacientes con displasia cervical, y preservan el ADN viral por 14 días si se almacenan en seco a temperatura ambiente. Se requieren estudios en población general para poder confirmar.
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Humanos , Testes de DNA para Papilomavírus Humano , Manejo de Espécimes , Esfregaço Vaginal , Programas de Rastreamento , AutoexameRESUMO
The level of Epstein-Barr virus DNA (EBV-DNA) in the plasma prior and subsequent to treatment is a reliable biomarker for the screening, diagnosis, monitoring and prognosis of nasopharyngeal carcinoma (NPC). The present retrospective study aimed to determine whether pre- and post-treatment levels of plasma EBV-DNA were predictive of survival in a large sample of patients with NPC. The level of plasma EBV-DNA in 637 NPC patients prior and subsequent to treatment was determined by quantitative polymerase chain reaction. The value of pre- and post-treatment plasma EBV-DNA in predicting the survival of NPC patients was then analyzed. The results revealed that pre-treatment plasma EBV-DNA loads were significantly higher in patients with NPC than those in healthy controls (P<0.001). The percentage of patients with positive plasma EBV-DNA was markedly higher prior to treatment (70.64%; median, 1150 copies/ml; range, 0-9.75×106 copies/ml) than following treatment (25.99%; median, 0 copies/ml; range, 0-3.83×106 copies/ml) (P<0.001). Patients with a high plasma EBV-DNA load presented with a higher clinical tumor classification, lymph node status, metastatic status and overall cancer stage. The risk of NPC relapse and mortality was higher in patients with pre-treatment plasma EBV-DNA levels of ≥1,500 copies/ml than that in patients with <1,500 copies/ml. Furthermore, the risk of relapse and mortality was higher in patients with positive post-treatment plasma EBV-DNA than in patients with negative post-treatment plasma EBV-DNA. Detectable post-treatment plasma EBV-DNA was the most significant prognostic factor to affect relapse-free survival, whilst metastasis was the prognostic factor with the greatest effect on overall survival. These data indicated that pre- and post-treatment levels of plasma EBV-DNA were able to predict the prognosis of NPC. This finding may provide novel references for research and clinical practice.
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PURPOSE: The purpose of this study was to assess ordering of human papillomavirus (HPV) testing for normal cervical cytology among low-risk women aged 30 to 65 years. METHODS: Audits of 833 cytology request forms for low-risk women completing a Papanicolaou smear, from January 2008 to April 2011, from 5 Michigan family medicine clinics determined HPV orders completed by the clinician performing the Papanicolaou smear. Multivariate logistic regression models examined differences in HPV test ordering by patient age at Papanicolaou test, provider status and sex, and clinic across sites. A Poisson regression model analyzed the annual number of HPV test orders over time. RESULTS: Cytology requests were completed by 622 faculty (75%), 169 residents/fellows (20%), and 42 nurse practitioner/physician assistants (NP/PAs) (5%). HPV testing for any cytology result was ordered on 324 request forms (39%) by residents/fellows (48%), faculty (38%), and NP/PAs (10%). Female providers were twice as likely as men to order HPV testing for any cytology result across all clinics and provider statuses (P < .001). There were significant differences in HPV test ordering among clinics. Between 2008 and 2011 annual cytology requests increased 46%, including HPV testing for any cytology result after adjusting for faculty provider sex. CONCLUSION: HPV test ordering when cytology is collected varied by clinic and provider status and sex. HPV co-testing for any cytology result remains modest, but is increasing over time in these clinics.
Assuntos
DNA Viral/análise , Programas de Rastreamento , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Médicos de Família , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Colposcopia , Diagnóstico Diferencial , Feminino , Humanos , Michigan/epidemiologia , Pessoa de Meia-Idade , Teste de Papanicolaou , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal/métodos , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologiaRESUMO
Introducción: los niveles de ADN viral en muestras de suero son un marcador útil para monitorear la progresión de la enfermedad y la respuesta al tratamiento en pacientes con hepatitis B crónica; de ahí que se comercialicen estuches diagnósticos para esta función, con la desventaja de ser costosos. Objetivos: desarrollar y evaluar el desempeño analítico de un sistema de reacción en cadena de la polimerasa en tiempo real para la cuantificación del ADN del virus de la hepatitis B. Métodos: se utilizaron cebadores que amplifican un fragmento del gen C y sonda de hidrólisis en el equipo LightCycler 1.5. Se construyó una curva estándar y se evaluó su eficiencia. Se utilizaron 272 muestras de suero para ensayos de especificidad analítica y clínica, especificidad y exactitud genotípica, coeficientes de variación intraensayo e interensayo, comparación con un estuche comercial y con la reacción en cadena de la polimerasa cualitativa para el virus de la hepatitis B. Resultados: la curva estándar mostró excelente correlación lineal (r= -1) y valores muy bajos de error a lo largo de varias magnitudes de concentración de ADN diana. La especificidad analítica y clínica fue de 100 %, en tanto que al evaluar la especificidad y exactitud genotípica, se obtuvo que las diferencias entre los Log10 del valor obtenido y el de referencia eran inferiores a 0,5 Log10. El límite de detección por análisis de Probit se estimó en 16,41 UI/µL con un rango dinámico de cuantificación de hasta 10(8) UI/mL. El sistema mostró bajos coeficientes de variación intraensayo (0,16 a 1,45 %) e interensayo (0,9 a 2,62 %). La comparación con el estuche comercial artus HBV LC PCR kit mostró una correlación de r= 0,964 y r²= 0,929; con la reacción en cadena de la polimerasa cualitativa se confirmó la mayor sensibilidad y (AU)
Introduction: viral DNA levels in serum samples are a useful marker to monitor the disease progression and the treatment response in patients with chronic hepatitis B. Commercial kits for this purpose are available, but they are considerably expensive. Objectives: to evaluate the analytical performance of a real-time polymerase chain reaction (RT-PCR) assay for Hepatitis B virus DNA quantification. Methods: specific primers to the gene C and TaqMan chemistry in a LightCycler 1.5 equipment was used. A standard curve was made and evaluated. Two hundred and seventy-two serum samples were used to assess the clinical and analytical specificity, the genotypic accuracy and specificity, the intra-assay and interassay coefficients of variation and the comparison with a commercial assay and with the qualitative PCR. Results: the standard curve showed a strong linear correlation (r= -1) and low error values in the tested target DNA concentration. Analytical and clinical specificities were 100 %. Genotype accuracy and specificity showed that the differences between the results obtained by RT-PCR assay and those of the reference assay were less than 0.5 Log10. The 95% HBV DNA detection end-point assessed by Probit analysis was 16.41 IU/µL with a dynamic range of quantification of 10(8) IU/mL. Intra-assay and interassay coefficients of variation ranged from 0.16 to 1.45 % and 0.9 to 2.62 % respectively. The RT-PCR assay correlated well with those from a commercial assay (r= 0.964 and r²= 0.929) and with the HBV qualitative PCR, thus confirming its better sensitivity and advantages. Conclusions: the RT-PCR assay is well suited to monitoring HBV DNA levels showing to be sensitive, specific and reproducible. Its application in the clinical practice ensures a better diagnosis and management of patients with chronic hepatitis B in Cuba.(AU)
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Humanos , DNA Viral/análise , Vírus da Hepatite B/genética , Reação em Cadeia da Polimerase em Tempo Real , CubaRESUMO
Introducción: los niveles de ADN viral en muestras de suero son un marcador útil para monitorear la progresión de la enfermedad y la respuesta al tratamiento en pacientes con hepatitis B crónica; de ahí que se comercialicen estuches diagnósticos para esta función, con la desventaja de ser costosos. Objetivos: desarrollar y evaluar el desempeño analítico de un sistema de reacción en cadena de la polimerasa en tiempo real para la cuantificación del ADN del virus de la hepatitis B. Métodos: se utilizaron cebadores que amplifican un fragmento del gen C y sonda de hidrólisis en el equipo LightCycler 1.5. Se construyó una curva estándar y se evaluó su eficiencia. Se utilizaron 272 muestras de suero para ensayos de especificidad analítica y clínica, especificidad y exactitud genotípica, coeficientes de variación intraensayo e interensayo, comparación con un estuche comercial y con la reacción en cadena de la polimerasa cualitativa para el virus de la hepatitis B. Resultados: la curva estándar mostró excelente correlación lineal (r= -1) y valores muy bajos de error a lo largo de varias magnitudes de concentración de ADN diana. La especificidad analítica y clínica fue de 100 %, en tanto que al evaluar la especificidad y exactitud genotípica, se obtuvo que las diferencias entre los Log10 del valor obtenido y el de referencia eran inferiores a 0,5 Log10. El límite de detección por análisis de Probit se estimó en 16,41 UI/µL con un rango dinámico de cuantificación de hasta 10(8) UI/mL. El sistema mostró bajos coeficientes de variación intraensayo (0,16 a 1,45 %) e interensayo (0,9 a 2,62 %). La comparación con el estuche comercial artus HBV LC PCR kit mostró una correlación de r= 0,964 y r²= 0,929; con la reacción en cadena de la polimerasa cualitativa se confirmó la mayor sensibilidad y ventajas de la reacción en cadena de la polimerasa en tiempo real. Conclusiones: el ensayo cumple con los requisitos para la cuantificación del ADN del virus de la hepatitis B, que demuestra ser específico, sensible y reproducible. Su aplicación permitirá un mejor diagnóstico y seguimiento de los pacientes con hepatitis B crónica en Cuba.
Introduction: viral DNA levels in serum samples are a useful marker to monitor the disease progression and the treatment response in patients with chronic hepatitis B. Commercial kits for this purpose are available, but they are considerably expensive. Objectives: to evaluate the analytical performance of a real-time polymerase chain reaction (RT-PCR) assay for Hepatitis B virus DNA quantification. Methods: specific primers to the gene C and TaqMan chemistry in a LightCycler 1.5 equipment was used. A standard curve was made and evaluated. Two hundred and seventy-two serum samples were used to assess the clinical and analytical specificity, the genotypic accuracy and specificity, the intra-assay and interassay coefficients of variation and the comparison with a commercial assay and with the qualitative PCR. Results: the standard curve showed a strong linear correlation (r= -1) and low error values in the tested target DNA concentration. Analytical and clinical specificities were 100 %. Genotype accuracy and specificity showed that the differences between the results obtained by RT-PCR assay and those of the reference assay were less than 0.5 Log10. The 95% HBV DNA detection end-point assessed by Probit analysis was 16.41 IU/µL with a dynamic range of quantification of 10(8) IU/mL. Intra-assay and interassay coefficients of variation ranged from 0.16 to 1.45 % and 0.9 to 2.62 % respectively. The RT-PCR assay correlated well with those from a commercial assay (r= 0.964 and r²= 0.929) and with the HBV qualitative PCR, thus confirming its better sensitivity and advantages. Conclusions: the RT-PCR assay is well suited to monitoring HBV DNA levels showing to be sensitive, specific and reproducible. Its application in the clinical practice ensures a better diagnosis and management of patients with chronic hepatitis B in Cuba.
Assuntos
Humanos , DNA Viral/análise , Vírus da Hepatite B/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
OBJECTIVE: To evaluate the prevalence of the urinary excretion of BKV and JCV in HIV-infected patients without neurological symptoms. METHODS: Urine samples from HIV-infected patients without neurological symptoms were tested for JC virus and BK virus by PCR. Samples were screened for the presence of polyomavirus with sets of primers complementary to the early region of JCV and BKV genome (AgT). The presence of JC virus or BK virus were confirmed by two other PCR assays using sets of primers complementary to the VP1 gene of each virus. Analysis of the data was performed by the Kruskal-Wallis test for numerical data and Pearson or Yates for categorical variables. RESULTS: A total of 75 patients were included in the study. The overall prevalence of polyomavirus DNA urinary shedding was 67/75 (89.3%). Only BKV DNA was detected in 14/75 (18.7%) urine samples, and only JCV DNA was detected in 11/75 (14.7%) samples. Both BKV and JCV DNA were present in 42/75 (56.0%) samples. CONCLUSION: In this study we found high rates of excretion of JCV, BKV, and simultaneous excretion in HIV+ patients. Also these results differ from the others available on the literature.
OBJETIVO: Avaliar a prevalência de excreção urinaria de vírus JC (VJC) e vírus BK (VBK) em pacientes HIV+ sem sintomas neurológicos. MÉTODOS: Amostras de urina de pacientes HIV+ sem sintomas neurológicos foram testados para a presença de VJC e VBK através da técnica de PCR. As amostras foram triadas para a presença de poliomavírus com par de primers complementares a região precoce do genoma do VBK e do VJC (AgT). A presença foi confirmada através de dois outros ensaios de PCR dirigidos a região do gene VP1 de ambos os vírus. A análise estatística foi realizada com auxílio do teste de Kruskal-Wallis para dados numéricos e Pearson ou Yater para variáveis categóricas. RESULTADOS: Ao todo foram inclusos no estudo 75 pacientes. A prevalência geral de excreção de poliomavírus na urina foi de 67/75 (89,3%). O DNA do vírus VBK foi detectado em 14/75 (18,7%) das amostras de urina, e o DNA do VJC foi detectado em 11/75 (14,7%) das amostras testadas. Ambos os vírus estavam presentes simultaneamente em 42/75 (56%) das amostras de urina. CONCLUSÃO: Encontramos, no presente estudo, uma alta taxa de excreção de VJC, VBK e excreção simultânea em pacientes HIV+. Ainda, esses resultados diferem de outros disponíveis na literatura.
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Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Vírus BK/isolamento & purificação , Vírus JC/isolamento & purificação , Infecções por Polyomavirus/diagnóstico , Urina/virologia , Infecções Oportunistas Relacionadas com a AIDS/urina , Infecções Oportunistas Relacionadas com a AIDS/virologia , Vírus BK/genética , DNA Viral/análise , Vírus JC/genética , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/urina , PrevalênciaRESUMO
O papilomavírus humano (HPV) é um vírus DNA que apresenta tropismo por células epiteliais, causando infecções na pele e nas mucosas. A replicação do HPV ocorre no núcleo das células escamosas e o seu ciclo de vida é diretamente relacionado ao programa de diferenciação da célula hospedeira. Até o momento, foram completamente caracterizados cerca de 100 tipos diferentes de HPVs e há um grande número adicional de tipos ainda não sequenciados. Além de ser o responsável por lesões benignas de pele e mucosas, o HPV também está envolvido no desenvolvimento de diversos tumores cutaneomucosos: doença de Bowen, cânceres de pele não melanoma e carcinomas genitais. Esta revisão aborda as características do HPV, quadros cutâneos e mucosos benignos e malignos causados por ele e os principais métodos empregados em sua detecção e tipagem.
Human papillomavirus (HPV) is a DNA virus that presents tropism for epithelial cells, causing infections of the skin and mucous membranes. Replication of HPV occurs in the nuclei of squamous cells and its life cycle is directly related to the differentiation program of the host cell. To date, nearly 100 different types of HPV have been characterized and there is a large number of other types that have not been sequenced yet. Besides being responsible for benign lesions of the skin and mucous membranes, HPV is also involved in the development of various mucocutaneous tumors: Bowen's disease, non-melanoma skin cancers and genital carcinomas. This review discusses the characteristics of HPV, malignant and benign mucous and skin manifestations caused by HPV, besides the main methods of detection and typing of the virus.
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Humanos , Papillomaviridae , Infecções por Papillomavirus/etiologia , Neoplasias Cutâneas/virologia , Infecções Tumorais por Vírus/etiologia , Verrugas/virologia , Filogenia , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Infecções Tumorais por Vírus/genética , Infecções Tumorais por Vírus/virologiaRESUMO
Human papillomavirus (HPV) has been established as an important etiological factor for the development of cervical cancer. This DNA virus primarily infects the epithelium and can induce benign and malignant lesions of the mucous membranes and skin. Some HPVs are considered high risk due to their role in malignant progression of cervical tumors. Genital HPV infections are common and usually transient among young sexually active women. Only a small fraction of infected women develop cervical cancer, implying the involvement of environmental and genetic cofactors in cervical carcinogenesis. Classification, virology, pathology, natural history, epidemiological features of genital HPV infection, and future prospects for cervical cancer prevention with HPV vaccines will be reviewed here.
O papilomavírus humano (HPV) é um fator etiológico bem estabelecido para o câncer cervical. Esse vírus de DNA infecta primariamente o epitélio e pode induzir lesões benignas ou malignas na pele e na mucosa. Alguns HPVs são considerados de alto risco, responsáveis pela progressão das lesões precursoras até câncer cervical. A infecção genital pelo HPV é comum em mulheres jovens e geralmente é transitória. Uma pequena proporção de mulheres infectadas desenvolve câncer cervical, implicando o envolvimento de fatores ambientais e fatores genéticos na carcinogênese. Essa revisão aborda a estrutura viral, classificação e patologia do HPV, história natural e fatores de risco para neoplasia cervical e perspectivas futuras com a vacina anti-HPV.
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Feminino , Humanos , Papillomaviridae/classificação , Infecções por Papillomavirus/virologia , Infecções Tumorais por Vírus/virologia , Neoplasias do Colo do Útero/virologia , Vacinas contra Papillomavirus , Prevalência , Infecções por Papillomavirus/epidemiologia , Fatores de Risco , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/epidemiologiaRESUMO
Recentemente é descrito estado de persistência do vírus da hepatite B denominado hepatite crônica B oculta. Sua prevalência e fisiopatologia são desconhecidas. O objetivo deste estudo foi avaliar a ocorrência dessa entidade clínica em pacientes da Amazônia brasileira. De 51 pacientes anti-HBc total reativos testados pela reação em cadeia da polimerase, 17 por cento foram positivos. Não observamos associação com fatores de risco clássicos de infecção pelo vírus da hepatite B, testes bioquímicos, hematológicos e histopatologia. No entanto, os pacientes ictéricos e reativos para o anti-HIV apresentaram associação com a presença do ADN-vírus da hepatite B. Os resultados demonstram a ocorrência da hepatite crônica B oculta, entre nossos doentes, porém, com taxas de prevalência abaixo do esperado para a região. Acreditamos que, apesar do tamanho da amostra avaliada ser pequeno, sua ocorrência poderia ter sido maior se empregássemos primers para a região S, C e X do genoma do vírus da hepatite B, aumentando a sensibilidade do teste.
A persistent form of the hepatitis B virus called occult chronic hepatitis B has recently been described. Its prevalence and physiopathology are unknown. The aim of this study was to evaluate the occurrence of this clinical entity among patients in the Brazilian Amazon region. Out of 51 anti-HBc total-positive patients who were tested using the polymerase chain reaction, 17 percent were positive. We did not find any associations with classical risk factors for hepatitis B virus infection or with biochemical tests, hematological tests or histological patterns. However, the jaundiced and HIV-positive patients showed a statistical association with the presence of hepatitis B virus-DNA. The results demonstrated that occult hepatitis B occurred among our patients, but at prevalence rates lower than expected for this region. We believe that despite the small sample size, the occurrence might have been found to be greater if we had used primers for the S, C and X regions of the hepatitis B virus genome, thereby increasing the sensitivity of the test.