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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Role of the 3'UTR in translation and stability of HCV and HPV mRNAs

Wiklund, Lisa January 2002 (has links)
<p>Virus mRNAs can be divided into functional regions. The focus of this thesis will be to investigate the function of one of these regions, the 3’ untranslated region (UTR). The 3’UTR of HCV contains a U-rich element and the late 3’UTR of HPV-1 contains an AU-rich element. The roles of these regions in translation and stability of HCV and HPV have been studied. </p><p>A method was established for studying translation of HCV mRNA in living cells. Noninfectious minivirus clones were synthesised <i>in vitro </i>and were transfected into cells by electroporation. This made it possible to bypass the nucleus and to transfer RNA directly into the cell cytoplasm. We found that HCV mRNAs that are translated from the HCV internal ribosome entry site (IRES) are inefficiently translated in comparison to capped and polyadenylated cellular mRNAs. Interestingly, the addition of a cap and a poly(A) tail resulted in a tremendous increase in the initiation of translation at the HCV IRES. This was the result of a discontinuous scanning or shunting mechanism. We also found that the 3’UTR had a small but not significant effect on the virus mRNA translation. Next, we set up an <i>in vitro </i>stability assay to investigate if HCV 3’UTR affects the stability of the virus mRNA. We found that the HCV 3’UTR is very unstable but interaction with the cellular La protein protects the mRNA from premature degradation.</p><p>In parallel experiments, we studied translation and stability of the HPV-1 late mRNAs. By studying an AU-rich sequence in the 3’UTR, we mapped two minimal inhibitory sequence elements, UAUUUAU and UAUUUUUAU that reduced mRNA half-life. We found that the same motifs in the AU-rich element inhibit mRNA translation, demonstrating that the AU-rich element acts via a bimodal mechanism to reduce mRNA stability and inhibit translation.</p>
192

Role of the 3'UTR in translation and stability of HCV and HPV mRNAs

Wiklund, Lisa January 2002 (has links)
Virus mRNAs can be divided into functional regions. The focus of this thesis will be to investigate the function of one of these regions, the 3’ untranslated region (UTR). The 3’UTR of HCV contains a U-rich element and the late 3’UTR of HPV-1 contains an AU-rich element. The roles of these regions in translation and stability of HCV and HPV have been studied. A method was established for studying translation of HCV mRNA in living cells. Noninfectious minivirus clones were synthesised in vitro and were transfected into cells by electroporation. This made it possible to bypass the nucleus and to transfer RNA directly into the cell cytoplasm. We found that HCV mRNAs that are translated from the HCV internal ribosome entry site (IRES) are inefficiently translated in comparison to capped and polyadenylated cellular mRNAs. Interestingly, the addition of a cap and a poly(A) tail resulted in a tremendous increase in the initiation of translation at the HCV IRES. This was the result of a discontinuous scanning or shunting mechanism. We also found that the 3’UTR had a small but not significant effect on the virus mRNA translation. Next, we set up an in vitro stability assay to investigate if HCV 3’UTR affects the stability of the virus mRNA. We found that the HCV 3’UTR is very unstable but interaction with the cellular La protein protects the mRNA from premature degradation. In parallel experiments, we studied translation and stability of the HPV-1 late mRNAs. By studying an AU-rich sequence in the 3’UTR, we mapped two minimal inhibitory sequence elements, UAUUUAU and UAUUUUUAU that reduced mRNA half-life. We found that the same motifs in the AU-rich element inhibit mRNA translation, demonstrating that the AU-rich element acts via a bimodal mechanism to reduce mRNA stability and inhibit translation.
193

Arrayed identification of DNA signatures

Käller, Max January 2005 (has links)
<p>In this thesis techniques are presented that aim to determine individual DNA signatures by controlled synthesis of nucleic acid multimers. Allele-specific extension reactions with an improved specificity were applied for several genomic purposes. Since DNA polymerases extend some mismatched 3’-end primers, an improved specificity is a concern. This has been possible by exploiting the faster extension of matched primers and applying the enzymes apyrase or Proteinase K. The findings were applied to methods for resequencing and viral and single nucleotide polymorphism (SNP) genotyping.</p><p>P53 mutation is the most frequent event in human cancers. Here, a model system for resequencing of 15 bps in p53 based on apyrase-mediated allele-specific extension (AMASE) is described, investigated and evaluated (Paper I). A microarray format with fluorescence detection was used. On each array, four oligonucleotides were printed for each base to resequence. Target PCR products were hybridized and an AMASE-reaction performed in situ to distinguish which of the printed oligonucleotides matched the target. The results showed that without the inclusion of apyrase, the resulting sequence was unreadable. The results open the possibilities for developing large-scale resequencing tools.</p><p>The presence of certain types of human papillomaviruses (HPV) transforms normal cells into cervical cancer cells. Thus, HPV type determination is clinically important. Also, multiple HPV infections are common but difficult to distinguish. Therefore, a genotyping platform based on competitive hybridization and AMASE is described, used on clinical sample material and evaluated by comparison to Sanger DNA sequencing (Papers II and III). A flexible tag-microarray was used for detection and the two levels of discrimination gave a high level of specificity. Easy identification of multiple infections was possible which provides new opportunities to investigate the importance of multiply infected samples.</p><p>To achieve highly multiplexed allele-specific extension reactions, large numbers of primers will be employed and lead to spurious hybridizations. Papers IV to VI focus on an alternative approach to control oligomerization by using protease mediated allele-specific extension (PrASE). In order to maintain stringency at higher temperatures, Proteinase K, was used instead of apyrase, leading to DNA polymerase degradation and preventing unspecific extensions. An automated assay with tag-array detection for SNP genotyping was established. First PrASE was introduced and characterized (Paper IV), then used for genotyping of 10 SNPs in 442 samples (Paper V). A 99.8 % concordance to pyrosequencing was found. PrASE is a flexible tool for association studies and the results indicate an improved assay conversion rate as compared to plain allele-specific extension.</p><p>The highly polymorphic melanocortin-1 receptor gene (MC1R) is involved in melanogenesis. Twenty-one MC1R variants were genotyped with PrASE since variants in the gene have been associated to an increased risk of developing melanoma. A pilot study was performed to establish the assay (Paper VI) and subsequently a larger study was executed to investigate allele frequencies in the Swedish population (Paper VII). The case and control groups consisted of 1001 and 721 samples respectively. A two to sevenfold increased risk of developing melanoma was observed for carriers of variants.</p>
194

Routine Anal Cytology Screening for Anal Squamous Intraepithelial Lesions in an Ethnically Diverse Urban HIV Clinic

Scott, Hyman 15 November 2006 (has links)
Anal cancer, like cervical cancer, is associated with Human Papillomavirus (HPV) infection. HIV+ patients have 38-60 fold increased risk of anal cancer compared to HIV- patients prompting many to suggest routine screening given the success of cervical Pap screening. Our goal is to describe our experience with routine anal Pap screening, determine which patients are most likely to have abnormal results, if anal disease on physical exam is predictive of cytology, and correlate cytology with histology findings. Charts of all patients with an anal Pap followed at the Hospital of Saint Raphael HIV Clinic were reviewed. Demographics, immune status, sexually transmitted disease history, cytology and histology data was extracted from medical charts. Patients with an anal Pap between November 1, 2002-November 30, 2004 were included. Those with an insufficient sample were excluded. Analysis was done using ÷2 for comparison of proportions and student t-test for continuous variables. Overall, 265/560 HIV+ patients had at least one anal Pap. Seventy-four of these 265 patients had an abnormal anal Pap. Mean age was 44 yrs, and 68% were men. Fifty-nine percent were African American, 34% White, and 17% Hispanic. Those with an abnormal Pap were more likely to be White (p=.03), and be gay or bisexual men (p=.02). They were also more likely to have lower CD4+ nadir (142 vs 223, p=.005) and CD4+ at time of anal Pap (353 vs 497, p<.001). Those with an abnormal anal Pap also had more anal disease (30% vs 9%, p<.001), history of warts (23% vs 12%, p=.02) and herpes (35% vs 22%, p=.02). Anal disease on physical exam had a sensitivity of 56% and specificity of 77% for abnormal cytology findings. On histology two patients had Anal Intraepithelial Neoplasia (AIN ) I, 2 AIN II, 3 AIN III, and 2 Squamous Cell Carcinoma In Situ. There was no correlation between cytology and histology. Routine anal cytology screening is a feasible tool to incorporate into an ethnically diverse HIV clinic for identifying precancerous anal lesions, a group which has been largely overlooked. Anal disease on physical exam is a poor predictor of abnormal cytology and there was no correlation between severity of disease on cytology and histology. However, further follow-up study is required to determine the impact on morbidity and mortality.
195

A Cross-National Analysis of the Human Papillomavirus, Sexually Transmitted Infections, and Sexual Behavior among Men

August, Euna Marie 01 January 2012 (has links)
There is a paucity of research on the risk for sexually transmitted infections (STIs) and sexual behavior among general populations of men. Research with male populations predominantly has focused on those subgroups considered to be at high risk of disease transmission, such as gay and bisexual men, injection drug users, and adolescents/young adults. Considerably fewer studies have examined factors among men, in general, and heterosexual men, specifically. Therefore, I conducted analyses with a cross-national sample of adult, sexually active men in Brazil, Mexico, and the United States to investigate sexual behaviors and risk factors associated with the human papillomavirus (HPV) and other STIs. The research questions were: 1) How does sexual risk differ among men residing in Brazil, Mexico, and the US by age cohort?; 2) Do men's sexual behaviors change after being tested for HPV and other STIs?; and 3) Do men's sexual behaviors change after being informed of diagnosis with HPV and other STIs? These research questions were explored through a quantitative assessment of secondary data collected through a risk factor questionnaire administered using computer assisted self-interviewing. The study findings underscore the need for public health interventions to address STI risk and transmission among men across the lifespan. Additionally, this study revealed the potential of STI testing as an effective strategy to reduce sexual risk-taking among men. While this research identifies key issues of importance in improving men's sexual health, additional research is needed to provide an enhanced contextual understanding of socio-cultural, interpersonal, and community level factors that affect sexual behaviors and decision-making among men.
196

Arrayed identification of DNA signatures

Käller, Max January 2005 (has links)
In this thesis techniques are presented that aim to determine individual DNA signatures by controlled synthesis of nucleic acid multimers. Allele-specific extension reactions with an improved specificity were applied for several genomic purposes. Since DNA polymerases extend some mismatched 3’-end primers, an improved specificity is a concern. This has been possible by exploiting the faster extension of matched primers and applying the enzymes apyrase or Proteinase K. The findings were applied to methods for resequencing and viral and single nucleotide polymorphism (SNP) genotyping. P53 mutation is the most frequent event in human cancers. Here, a model system for resequencing of 15 bps in p53 based on apyrase-mediated allele-specific extension (AMASE) is described, investigated and evaluated (Paper I). A microarray format with fluorescence detection was used. On each array, four oligonucleotides were printed for each base to resequence. Target PCR products were hybridized and an AMASE-reaction performed in situ to distinguish which of the printed oligonucleotides matched the target. The results showed that without the inclusion of apyrase, the resulting sequence was unreadable. The results open the possibilities for developing large-scale resequencing tools. The presence of certain types of human papillomaviruses (HPV) transforms normal cells into cervical cancer cells. Thus, HPV type determination is clinically important. Also, multiple HPV infections are common but difficult to distinguish. Therefore, a genotyping platform based on competitive hybridization and AMASE is described, used on clinical sample material and evaluated by comparison to Sanger DNA sequencing (Papers II and III). A flexible tag-microarray was used for detection and the two levels of discrimination gave a high level of specificity. Easy identification of multiple infections was possible which provides new opportunities to investigate the importance of multiply infected samples. To achieve highly multiplexed allele-specific extension reactions, large numbers of primers will be employed and lead to spurious hybridizations. Papers IV to VI focus on an alternative approach to control oligomerization by using protease mediated allele-specific extension (PrASE). In order to maintain stringency at higher temperatures, Proteinase K, was used instead of apyrase, leading to DNA polymerase degradation and preventing unspecific extensions. An automated assay with tag-array detection for SNP genotyping was established. First PrASE was introduced and characterized (Paper IV), then used for genotyping of 10 SNPs in 442 samples (Paper V). A 99.8 % concordance to pyrosequencing was found. PrASE is a flexible tool for association studies and the results indicate an improved assay conversion rate as compared to plain allele-specific extension. The highly polymorphic melanocortin-1 receptor gene (MC1R) is involved in melanogenesis. Twenty-one MC1R variants were genotyped with PrASE since variants in the gene have been associated to an increased risk of developing melanoma. A pilot study was performed to establish the assay (Paper VI) and subsequently a larger study was executed to investigate allele frequencies in the Swedish population (Paper VII). The case and control groups consisted of 1001 and 721 samples respectively. A two to sevenfold increased risk of developing melanoma was observed for carriers of variants. / QC 20101028
197

MAPKs regulate nuclear import of human papillomavirus type 11 replicative helicase E1

Yu, Jei-Hwa. January 2008 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed June 5, 2008). Includes bibliographical references.
198

Conhecimento e atitude de enfermeiros sobre câncer do colo do útero, infecção pelo Papilomavirus humano vacinas contra Papilomavirus humano e vacinas contra Papilomavirus humano

Souza, Sandra Ely Barbosa de January 2015 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-11-16T14:07:55Z No. of bitstreams: 1 Sandra Ely Barbosa de Souza. Conhecimento e atitude...pdf: 1144576 bytes, checksum: 1cae38c0f9d2b1407f11598592cf5b02 (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-11-16T14:10:18Z (GMT) No. of bitstreams: 1 Sandra Ely Barbosa de Souza. Conhecimento e atitude...pdf: 1144576 bytes, checksum: 1cae38c0f9d2b1407f11598592cf5b02 (MD5) / Made available in DSpace on 2015-11-16T14:10:18Z (GMT). No. of bitstreams: 1 Sandra Ely Barbosa de Souza. Conhecimento e atitude...pdf: 1144576 bytes, checksum: 1cae38c0f9d2b1407f11598592cf5b02 (MD5) Previous issue date: 2015 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / INTRODUÇÃO: A infecção viral pelo Papilomavírus Humano (HPV) é a mais frequente entre as mulheres no inicio da vida sexual, cuja persistência pode determinar câncer do colo do útero. O câncer do colo do útero pode ser prevenido secundariamente com triagem cervical e primariamente com vacinas para HPV, No Brasil, a vacina quadrivalente contra HPV passou a fazer parte do Programa Nacional de Imunização a partir de 2014, tendo como publico alvo meninas de 11 a 13 anos. O conhecimento dos enfermeiros sobre HPV, câncer cervical e vacinas contra HPV é importante para o sucesso do programa de vacinação. OBJETIVO: Avaliar o conhecimento e as atitudes de enfermeiros sobre câncer do colo do útero, infecção pelo HPV e vacinas contra HPV. Objetivos específicos: estimar a aceitabilidade da vacina contra HPV entre enfermeiros e identificar barreiras/obstáculos e facilitadores para a aceitação da vacina contra HPV por enfermeiros. MATERIAIS E MÉTODOS: Estudo de corte transversal, realizado com enfermeiros cadastrados no Conselho Regional de Enfermagem da Bahia. Foi enviado um questionário postado no SurveyMonkey®, via mala direta, sob a forma de link, para os enfermeiros com cadastro no conselho. O projeto foi aprovado previamente pelo comitê de ética em pesquisa da FIOCRUZ. RESULTADOS: Participaram do inquérito 1.283 enfermeiros, na sua maioria mulheres, pardas, casadas, Especialistas, atuando na área assistencial e na rede pública. Foram categorizados por tempo de graduação, sexo e local de atuação. Apesar de a maioria conhecer o HPV (99%) e saber da associação com o câncer cervical (98%), muitos desconhecem que o HPV também causa verrugas (10%) e acreditam que a camisinha protege completamente contra o HPV (59%). Os enfermeiros não conhecem as recomendações do Ministério da Saúde sobre a triagem do câncer cervical, acreditam que esse exame é muito sensível para detecção de lesões pelo HPV (95%). Desconhecem que o HPV pode causar câncer em outros sítios (47%) e em homens (40%). Estes achados não diferem significativamente por sexo. Os enfermeiros atuando na rede pública parecem conhecer menos sobre HPV, câncer e vacinas contra HPV. A quase totalidade (99,5%) aceita a vacina contra HPV. Itens facilitadores da aceitabilidade incluem: acreditar em vacinas como forma de prevenção, segurança da vacina e a prevenção do câncer de colo uterino. As barreiras identificadas foram: receio de eventos adversos, pouca idade da filha e falta de recomendação médica. CONCLUSÕES: Os enfermeiros conhecem moderadamente sobre HPV, câncer do colo do útero e vacinas contra HPV porém existem importantes lacunas nesse conhecimento. Os graduados há menos de cinco anos parecem conhecer menos, embora devessem estar mais atualizados. Os enfermeiros da rede pública conhecem menos que os da rede privada. / INTRODUCTION: The viral infection with Human Papillomavirus (HPV) is the most common among women after sexual debut, the persistence of which can determine cervical cancer. Cervical cancer can be secondly prevented by cervical screening and primarily by HPV vaccines. In Brazil, the HPV quadrivalent vaccine has become part of the National Immunization Program since 2014, targeting girls aged 11 to13 years old. The knowledge of nurses about HPV, cervical cancer and HPV vaccines is important for success of vaccination programs. OBJECTIVE: To evaluate knowledge and attitudes of nurses about cervical cancer, HPV infection and HPV vaccines. Specific objectives: to estimate the acceptability of HPV vaccine among nurses and identify barriers/obstacles and facilitators to accept the HPV vaccine by nurses. MATERIAL AND METHODS: A cross-sectional study carried out with nurses registered in the Regional Council of Nursing in Bahia. A questionnaire posted at the SurveyMonkey®, was sent via direct mail, in the form of link, to all nurses with registered in the board. The project was approved by the Ethics Research Committee of FIOCRUZ. RESULTS: Overall, 1,283 nurses took part in this survey, most of them women: mixed race, married, specialists, and working in patients’ assistance and on the public sector. They were stratified by time of graduation, gender and workplace. Even though most of them were aware of HPV (99%) and knew its relation to cervical cancer (98%), many were unaware that HPV causes warts (10%) and also believe that the use of condom protects against HPV (59%) successfully. The nurses did not know about the Ministry of Health recommendations regarding screening for cervical cancer, and believed that such test has high sensitivity for the detection of HPV lesions (95%). They were unaware of HPV as a cause of cancer in other sites (47%) and in men (40%). These findings did not differ significantly by gender. The nurses working in the public sector seemed to know less about HPV, cancer and HPV vaccines than those working in the private sector. Almost all accepted the HPV vaccine (99,5%). Facilitators items of acceptability included: to believe in vaccines as prevention, the vaccine safety and the prevention of cervical cancer. The barriers identified were: fear of adverse events, believing the daughter was too young and a lack of medical recommendation. CONCLUSION: Nurses moderately know about HPV, cervical cancer and HPV vaccines but there are important gaps in this knowledge. Those graduating less than five years ago seemed to know less about HPV. Also, nurses in the public sector less about HPV than those in the private sector.
199

Papilomavírus humano e prognóstico de tumores de cabeça e pescoço / Human papillomavirus and prognostic of head and neck cancer

Rossana Verónica Mendoza López 12 December 2011 (has links)
Introdução. O Papilomavírus humano (HPV), particularmente o tipo 16, têm sido associado com risco e prognóstico de tumores de cabeça e pescoço. Contudo, o papel do DNA do HPV e resposta sorológica na sobrevida neste grupo de pacientes ainda não está claro. Objetivos. Avaliar o efeito do HPV (resposta sorológica e detecção do DNA no tecido tumoral) na sobrevida de pacientes com carcinoma epidermóide de cabeça e pescoço, considerando-se as distintas localizações anatômicas (cavidade oral, orofaringe, hipofaringe e laringe). Material e métodos. Coorte de 1.475 pacientes com carcinoma epidermóide de cabeça e pescoço, oriundos de dois estudos multicêntricos, diagnosticados entre novembro de 1998 e dezembro de 2008 e acompanhados até 30 de junho de 2009. Detecção de DNA do HPV no tecido tumoral foi feita pela técnica de PCR (Polymerase Chain Reaction) em tecido fresco e material parafinado. Resposta sorológica às proteínas do HPV foi determinada pela técnica Multiplex Luminex. Sobrevida global e específica pela doença foram calculadas pelo método atuarial (tábuas de vida). Curvas de sobrevida de Kaplan-Meier e teste Log-rank para comparação de curvas de sobrevida foram calculados. Hazard ratio (HR) do efeito da infecção pelo HPV nos tumores de cabeça e pescoço e respectivo intervalo com 95 por cento de confiança (IC95 por cento ) foram calculados via modelo de regressão de Cox ajustado pelas variáveis: estudo de origem dos casos, sexo, idade, educação, consumo de tabaco e de álcool, estadiamento do tumor e tratamento, assim como hábitos sexuais para a subcoorte com esta informação. Resultados. Prevalência de DNA do HPV 16 no tecido tumoral foi de 6,7 por cento nos casos recentes (2003-2008) comparado com 1 por cento nos casos iniciais (1998-2002) para a subcoorte de São Paulo. Aumento da soropositividade para HPV 16 E7 nos casos do estudo mais recente (2003-2008) comparado com os casos do estudo inicial (1998-2002) resultou estatisticamente significante. Foi observada pobre concordância entre os resultados de sorologia e DNA do HPV. Pacientes mais jovens (50 anos), que não fumavam e com tumores de orofaringe apresentaram risco aumentado na resposta sorológica à proteína E6 do HPV 16. Prática de sexo oral associou-se com resposta sorológica conjunta às proteínas E6 e E7 do HPV 16. Pacientes soropositivos para HPV 16 E6 apresentaram maior sobrevida global (HR=0,62; IC95 por cento =0,44-0,87), adicionalmente observou-se que a resposta sorológica conjunta às proteínas E6 e E7 do HPV incrementou a sobrevida dos pacientes com tumores de cabeça e pescoço (HR=0,34; IC95 por cento 0,17-0,70) e de orofaringe (HR=0,17; IC95 por cento 0,05-0,59). Conclusões. A prevalência da infecção pelo HPV entre pacientes com tumores de cabeça e pescoço aumentou no período estudado. O estudo sugere que resposta sorológica conjunta às proteínas E6 e E7 do HPV 16 pode estar associada com maior sobrevida global nos tumores de cabeça e pescoço, especificamente nos pacientes com tumores de orofaringe / Introduction. Human papillomavirus (HPV), especially type 16, had been associated with risk and prognostic of head and neck cancer. However, the role of HPV DNA and serological response in survival of patients with head and neck cancer is not yet clear. Objectives. Evaluate the effect of HPV (serological response and HPV DNA tumor status) in survival of patients with squamous cell carcinoma of head and neck (SCCHN), according to anatomical sites (oral cavity, oropharynx, hypopharynx and larynx). Material and methods. Cohort of 1,475 patients with SCCHN, from two multicentre studies diagnosed between November 1998 and December 2008 and followed-up until 30 of June 2009. HPV DNA detection was evaluated by PCR (Polymerase Chain Reaction) in fresh tissue and paraffin blocks. Antibodies to HPV in the serum were determinated by Multiplex Luminex technique. Overall and disease specific survival were calculated by actuarial method. Kaplan-Meier survival curves and Log-rank test in order to compare survival curves were calculated. Hazard ratio (HR) and 95 per cent of interval confidence (95 per cent IC) for Cox model regression were used to evaluate the effect of HPV infection in SCCHN, adjusted by variables: study group, sociodemographics, tobacco and alcohol consumption, tumor clinical stage and treatment, and also sexual habits in the subcohort with available information. Results. HPV DNA 16 tumoral status prevalence was 6.7 per cent in recent cases (2003-2008) compared to 1 per cent in old cases (1998-2002), only for subcohort of São Paulo. Seropositivity to HPV 16 E7 increased in the late cases (2003-2008) compared to old cases (1998-2002) and was statistically significant. Poor concordance was showed between DNA HPV and serological response to HPV. Younger patients (50 years old), no smokers and with oropharyngeal tumors showed increased risk to HPV 16 E6 serological response. Oral sex was associated with HPV 16 E6 and E7 simultaneously. Seropositivity to HPV 16 E6 had longer overall survival (HR=0.62; 95 per cent CI=0.440.87), additionally HPV 16 E6 and E7 serological response increased the survival of head and neck cancers (HR=0.34; 95 per cent CI 0.17-0.70) and oropharyngeal cancer (HR=0.17; 95 per cent CI 0.05-0.59) Conclusions. Prevalence of HPV infection in patients with SCCHN had increased in the study period. The study suggests that HPV 16 E6 serological response could be associated with increased overall survival in patients with SCCHN tumors and specifically with oropharyngeal cancer
200

Detecção e genotipagem do papilomavírus humano (HPV) em mucosa oral de pacientes do Estado de Sergipe, Brasil / Detection and genotyping of Human Papillomavirus (HPV) in oral mucosa of patients in Sergipe State, Brazil

Ribeiro, Mariana Goveia Melo 29 August 2014 (has links)
Infection with Human Papillomavirus (HPV) is the sexually transmitted viral disease most prevalent in world. The infections can range from asymptomatic establishment to induction of squamous cell carcinomas. It has been discussed the correlation of HPV infection and the development and/or aggravation of lesions in the oral mucosa. The aim of this study was to evaluate the occurrence of HPV and its genotypes in patients with oral lesions and in healthy oral mucosa of users and non-users of drugs in the state of Sergipe, Brazil. Thirty-nine patients aged 2 to 83 years with clinically detectable lesions in the oral mucosa and 106 patients with healthy oral mucosa between 11 and 79 years were evaluated. Samples were collected by exfoliating the oral mucosa. For quality control of DNA extraction beta-globin PCR was performed. HPV DNA was detected using primers MY09/MY11 and GP5+/GP6+. Genotyping was performed by multiplex-PCR with specific primers for HPV types 6, 16 and 18. Our study detected the virus in all types of lesions evaluated. The occurrence of HPV was 76.92% (30/39) in patients with oral lesions. The most common virus type was HPV-6 in 56.67% (17/30), followed by HPV-18 in 26.67% (8/30) and HPV-16 in 6.67% (2/30). Positive results were found in 83.02% (88/106) of patients with healthy oral mucosa. The most common virus type was HPV-6 in 45.45% (40/88), followed by HPV-18 in 35.23% (31/88) and HPV-16 in 4.54% (4/88). Between multiple drug users 86.67% (52/60) were positive and multiple HPV infections were identified in 23.08% (12/52). At |non-users| the occurrence was 78.26% (36/46). A high occurrence of HPV was found in the study, both in oral lesions and in healthy mucosa. Rates of HPV detection in the oral cavity vary markedly in the world and make the relationship between HPV and oral carcinogenesis still controversial. Additional studies to evaluate the role of human papillomavirus in the development of lesions in the oral mucosa are necessary. There are few data available on the frequency of oral HPV infection in Brazilian population and especially among drug users. Other studies on HPV prevalence among drug users are needed for a better understanding of their exposure to the virus and for the development of prevention strategies. / A infecção pelo Papilomavírus Humano (HPV) é a doença viral sexualmente transmissível mais prevalente no mundo. Suas infecções podem variar de assintomáticas à indução de Carcinomas de Células Escamosas. Entre os agentes infecciosos associados ao câncer oral, tem-se discutido a correlação da infecção por HPV em mucosa oral e o desenvolvimento e/ou agravamento das lesões. O objetivo deste estudo foi avaliar a ocorrência do HPV e seus genótipos em pacientes com lesão oral e em mucosa oral saudável de usuários e não-usuários de drogas no estado de Sergipe, Brasil. Foram avaliados 39 pacientes com idade entre 2 e 83 anos, com lesões clinicamente detectáveis na mucosa oral e 106 pacientes com mucosa oral saudável entre 11 e 79 anos. As amostras foram coletadas por esfoliação da mucosa oral. Para o controle de qualidade da extração de DNA foi utilizado PCR para beta-globina. DNA-HPV foi detectado utilizando primers MY09/MY11 e GP5+/GP6+. A genotipagem foi realizada através de multiplex-PCR com primers específicos para os tipos virais 6, 16 e 18. Nosso estudo detectou DNA-HPV em todos os tipos de lesões avaliadas. A prevalência do HPV foi de 76,92% (30/39) nos pacientes com lesões orais. O tipo viral mais frequente foi o HPV-6, presente em 56,67% (17/30), seguido do HPV-18 em 26,67% (8/30) e do HPV-16 em 6,67% (2/30). DNA-HPV foi encontrado em 83,02% (88/106) dos pacientes com mucosa oral sadia. O tipo viral mais frequente foi o HPV-6, presente em 45,45% (40/88), seguido do HPV-18 em 35,23% (31/88) e do HPV-16 em 4,54% (4/88). Entre usuários de múltiplas drogas 86,67% (52/60) foram positivos e infecções múltiplas por mais de um tipo viral foram identificadas em 23,08% (12/52) dos indivíduos. Entre os "não usuários" a taxa de infecção pelo HPV foi de 78,26% (36/46). Desta forma, foi verificada uma alta ocorrência do HPV em nosso estudo, tanto em lesões orais quanto em mucosas saudáveis. As taxas de detecção do vírus em cavidade oral variam acentuadamente no mundo e tornam a relação do HPV com o processo de carcinogênese oral ainda controversa. Isso faz necessária a realização de estudos adicionais que avaliem o papel do Papilomavírus Humano no desenvolvimento de lesões na mucosa oral. Há poucos dados disponíveis sobre a frequência de infecção oral por HPV na população brasileira e especialmente entre usuários de drogas. Novos estudos sobre a prevalência do HPV entre usuários de drogas são necessários para melhor compreensão da sua exposição ao vírus e o desenvolvimento de estratégias de prevenção.

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