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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.
231

Botswana’s Adult Identity Mentoring Program (AIM) Public Health Evaluation: The Importance of Counseling and Education to Reduce the Psychosocial Impact on Asymptomatic Youth Diagnosed with Herpes Simplex Virus Type 2

Granados, Carolina 20 December 2012 (has links)
Background: The Division of Global HIV/AIDS at the Centers for Disease Control and Prevention (CDC) is working on a public health evaluation (PHE) in the eastern districts of Botswana. This PHE aims to evaluate the effectiveness of Project AIM, a group-level intervention designed to reduce HIV risk behaviors in youth ages 11 to 14, when combined with the regular Botswana Skills for Life Curriculum, a standard HIV prevention education curriculum in Botswana schools. In order to evaluate Project AIM, a self-report survey and a biological testing for herpes simplex virus type 2 (HSV-2) will be conducted. Methodology: Based on studies done on the psychosocial impact of HSV-2 diagnosis on asymptomatic individuals in the USA, the literature recommends providing pre and post counseling and education to individuals testing for genital herpes to help cope and diminish the psychosocial impact of the diagnosis. In order to prepare Botswana’s clinics and schools participating in the PHE to provide the support for newly diagnosed adolescents with HSV-2, guidance materials were developed for health care practitioners and school guidance teachers. Materials were created using Information Mapping technique to analyze, organize, and present the information, and the Microsoft Office Flesch Kinkade Grade Level (FK) tool to assess the readability levels of the materials. Results: Guidance materials were prepared using the 7±2 theoretical limit of human short-term memory information mapping rule, and the FK grade levels of 6.0 to 8.0 recommended readability scores. Guidance materials included information regarding HSV-2 symptoms, treatment, and prevention. They also included information on the PHE study, youth friendly health services, counseling and education, clinic referrals and contact information. Conclusions: The development of guidance materials for schools and clinic participants of the CDC PHE in Botswana will provide health practitioners and school guidance teachers with accurate HSV-2 information to counsel and educate student participants in this research study. The guidance materials should help students cope with potential psychosocial disorders associated with pre and post diagnosis of HSV-2.
232

Investigation of the deregulated miRNome identified during acute viral infections in a murine model of HSV-1 encephalitis

Caligiuri, Kyle January 2013 (has links)
Herpes simplex virus type 1 (HSV-1) is a double stranded DNA virus that causes epithelial skin infections and persists through the life of the host by infecting neurons, where it can switch to a latent state to evade an immune response. In rare cases during primary infection or after reactivation, instead of undergoing lytic infection at the epithelial surface, it instead travels to the brain and causes herpes simplex virus encephalitis (HSVE) which can have a ≥70% mortality rate if untreated. As the virus takes over its host cell, it gains control of the host cell machinery and manipulates host gene expression in order to evade the immune system and to pool its resources into the replication of the virus. One aspect of the dysregulated gene expression involves microRNAs (miRNAs). MiRNAs are short, non-coding RNAs that bind to the 3' untranslated region (3'UTR) of messenger RNAs (mRNAs), leading to translational repression of the target. Dysregulated miRNAs are often down-regulated during infection as the virus takes over, but many miRNAs have also been found to be up-regulated as well1–5. The aim of this study is to observe the full cellular miRNA changes in the context of an acute viral encephalitic infection using HSV-1, and to further characterize selected up-regulated miRNAs to determine their function in the context of the disease state. Of particular note were miR-141 and miR-200c which showed anti-apoptotic effects on neuronal cell culture and did not impact cell viability during an over-expression of the miRNAs. MiR-141, miR-183 and miR-200a expression was enriched within specific areas of the brain during infection. In addition, the potential for miR-150 to bind to a bioinformatically predicted target site within the shared 3'UTR of the HSV-1 UL18, UL19 and UL20 genes was explored. Examining the changes in expression of this class of regulatory RNAs and investigating their potential functions may yield new insight into the relationship between host and virus during infection.
233

Ensaios toxicológicos, não clínico e clínicos fase I e II, com o antiviral tópico celodenina no tratamento de herpes labial recorrente / Non-clinical and clinical phase I and II toxicological tests with topical antiviral celodenina in the treatment of recurrent herpes labialis

Cunha, Mônica Lorena Dias Meirelles da 21 November 2014 (has links)
Made available in DSpace on 2015-05-14T13:00:08Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1948005 bytes, checksum: 96df7a3d564809417a83d020664df9fc (MD5) Previous issue date: 2014-11-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Herpes simplex labialis, one of the most prevalent viral infections worldwide, is a chronic, relapsing incurable disease, persist throughout the lifetime of the host, usually in a latent form. Facing the difficulty of finding an effective therapy to traditional medicine, we seek new possibilities in complementary medicine treatment for this condition. The study aimed to perform non-clinical and clinical phase I and II toxicological tests with topical antiviral celodenina, neoflavonide synthesized from the ethanol extract of the stem bark of Coutarea hexandra (Jacq) K. Shum, topically. Preclinical studies have evaluated the dermal primary skin irritation - acute effect (single dose) and acute eye irritation (single dose) and in both experiments albino rabbits Zealanders, healthy adults were used in number 12, being 6 males and 6 females (control and treated) at a dose of 0.5 g of the cream. The assessment of primary skin irritation demonstrated that the cream does not irritate the skin of rabbits tested in Drug Testing Laboratory of the Federal University of Paraíba, since none showed any degree of erythema and edema throughout the experiment. Regarding eye irritation simple, cream showed low irritant effect, as only 33.3% rabbits showed redness in conjunctiva during the first 24 hours after application of the test substance. Did not identify any changes in the iris and cornea, in any animal throughout the experiment. To investigate the clinical phase I toxicity in humans, the celodenina, 30 volunteers were selected, of both sexes, clinically healthy, aged between 18 and 65 years. Study participants were treated daily, the night shift, by dermal route, with the cream for a period of four weeks and evaluated before the start of the study and after its termination hematology (CBC), biochemical (glucose, urea, creatinine, total cholesterol, AST, ALT, alkaline phosphatase), in order to detect possible changes resulting from use of cream in them, as well as to compare the results before and after the study. No abnormal values for both hematological variables as for biochemical between times and groups were highlighted. During treatment with the cream, some adverse reactions were observed in participants: local dryness (7%), burning (13%), tingling (7%) and erythema (7%), but the number of affected subjects was small, and symptoms and signs reported occurred in the first week of the study, not requiring specific treatment, disappearing spontaneously. Clinical phase II trials were randomized, double-blind, comparing celodenina 4% with placebo in 33 patients with recurrent herpes labialis between 18 and 65 years, who used these substances three times daily for 15 days. Patients were also assessed before and after the study of hematological and biochemical tests, which showed no significant values between times. Few adverse effects were reported, burning (21%) and local dryness (5.3%), both mildly during the first 30 minutes after application in the first five days. Herpes recurrences were evaluated for 30, 60 and 90 days and the participants treated with celodenina 4% had lower percentage of same relative to placebo at all time. These results suggest a low toxicity of the product, satisfactorily efficient control of relapses and indicate that this formulation can be used in Phase III clinical trials, dose and route of administration tested in the treatment of recurrent herpes labialis. / O herpes simples labial, uma das infecções virais mais prevalentes no mundo, é doença crônica, recidivante e incurável, persistindo durante toda a vida do hospedeiro, geralmente sob a forma latente. Frente à dificuldade de se encontrar uma terapia eficaz com a medicina tradicional, busca-se na medicina complementar novas possibilidades de tratamento para esta patologia. O estudo objetivou realizar ensaios toxicológicos, não clínico e clínicos fase I e II, com o antiviral celodenina, neoflavonoide sintetizado, a partir do extrato etanólico das cascas do caule de Coutarea hexandra (Jacq) K. Shum, via tópica. Os estudos dermais não clínicos avaliaram a irritação primária da pele efeito agudo (dose simples) e a irritação ocular aguda (dose simples) e em ambos os experimentos foram utilizados coelhos albinos neozelandeses, sadios, adultos, em número de 12, sendo 6 machos e 6 fêmeas (controle e tratado) para uma dose de 0,5 g do referido creme. A avaliação da irritação primária da pele demonstrou que o creme não é irritante para a pele dos coelhos testados no Laboratório de Ensaios Toxicológicos da Universidade Federal da Paraíba, já que nenhum deles apresentou nenhum grau de eritema e edema durante todo o experimento. Em relação à irritação ocular simples, o creme demonstrou efeito de baixa irritabilidade, porque apenas 33,3% coelhos apresentaram rubor em conjuntiva nas primeiras 24 horas após a aplicação da substância em estudo. Não foi identificada nenhuma alteração na íris e na córnea, em qualquer dos animais em todo o experimento. Para investigar a toxicidade clínica fase I, em seres humanos, da celodenina, foram selecionados 30 voluntários, de ambos os sexos, clinicamente saudáveis, com faixa etária compreendida entre 18 e 65 anos. Os participantes do estudo foram tratados diariamente, no turno da noite, por via dermal, com o creme por um período de 4 semanas e avaliados antes do início do estudo e após o seu término com exames hematológicos (hemograma completo), bioquímicos (glicemia, uréia, creatinina, colesterol total, AST, ALT, fosfatase alcalina), com o objetivo de detectar possíveis alterações decorrentes da utilização do creme nos mesmos, bem como, comparar os resultados antes e após o término do estudo. Não foram evidenciados valores alterados, tanto para as variáveis hematológicas como para as bioquímicas entre os tempos e os grupos. Ao longo do tratamento com o creme, foram observadas algumas reações adversas nos participantes: ressecamento local (7%), ardor (13%), formigamento (7%) e eritema (7%), mas o número de voluntários acometidos foi pequeno, e os sintomas e sinais relatados ocorreram na primeira semana do estudo, não necessitando de tratamento específico, desaparecendo espontaneamente. Os estudos clínicos fase II foi randomizado, duplo-cego, comparando a celodenina 4% com placebo em 33 pacientes portadores de herpes labial recorrente entre 18 e 65 anos, que utilizaram as referidas substâncias 3 vezes ao dia durante 15 dias. Os pacientes também foram avaliados antes e após o término do estudo com exames hematológicos e bioquímicos, os quais não demonstraram valores significativos entre os tempos. Poucos efeitos adversos foram relatados, o ardor (21%) e o ressecamento local (5,3%), ambos, de forma branda, durante os primeiros 30 minutos após a aplicação nos primeiros 5 dias. As recidivas herpéticas foram avaliadas durante 30, 60 e 90 dias e os participantes tratados com celodenina 4% apresentaram menor percentual das mesmas em relação ao placebo em todos os tempos. Estes resultados sugerem a baixa toxicidade do produto, eficiência satisfatória no controle das recidivas e indicam que esta formulação pode ser utilizada para testes clínicos fase III, na dose e via de administração testada no tratamento do herpes labial recorrente.
234

CaracterizaÃÃo fÃsico-quÃmica e estrutural de polissacarÃdeos obtidos de folhas da planta Aloe barbadensis Miller e avaliaÃÃo de suas atividades antiviral e anti-hemorrÃgica / Physico-chemical characterization and structural polysaccharides obtained from leaves of the plant Aloe barbadensis Miller and evaluation of their activities antiviral and anti-haemorrhagic

Ygor Raphael Gomes Eloy 22 March 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho teve como objetivos caracterizar fÃsico-quÃmica e estruturalmente polissacarÃdeos obtidos de folhas de Aloe barbadensis e avaliar suas atividades antiviral, anti-hemorrÃgica e prÃ-coagulante e possÃveis sinais de toxicidade. Foi realizada extraÃÃo aquosa de polissacarÃdeos totais (PT) de A. barbadensis, seguido de precipitaÃÃo por etanol e remoÃÃo dos contaminantes proteicos com TCA. A cromatografia em DEAE-celulose foi eficiente no fracionamento dos PT, onde foram obtidas as fraÃÃes PI e PII. A caracterizaÃÃo fÃsico-quÃmica mostrou que a fraÃÃo PI à composta por manose (78,4%), glucose (7,3%), galactose (2,1%), fucose (2,8%) e Ãcidos urÃnicos (10,0%), e isenta de grupos Ãster sulfato. Enquanto, a fraÃÃo PII à constituÃda por manose (39,2%), glucose (22,2%), galactose (26,3%), arabinose (3,8%), xilose (1,1%), Ãcidos urÃnicos (8,0%) e grupos Ãster sulfato (12,0%). Na revelaÃÃo das bandas polissacarÃdicas da fraÃÃo PII, obtidas por PAGE e gel de agarose corados com stainsall foi constatado a presenÃa de duas bandas que apresentaram diferentes coloraÃÃes, roxa e ciana, correspondentes a presenÃa de grupos sulfato e carboxilados, respectivamente. Na anÃlise estrutural das fraÃÃes PI e PII, por espectroscopia no IR, foi demonstrado que a fraÃÃo PI apresenta unidades monossacarÃdicas de Ã-manose O-acetiladas (812,2 e 960 onda.cm-1) e Ãcidos urÃnicos neutros (1738 onda.cm-1) em sua estrutura. Diferentemente, a fraÃÃo PII, mostrou-se ser constituÃda por unidades monossacarÃdicas de manose (1014,7 onda.cm-1), galactose (1078,2 onda.cm-1), Ãcidos urÃnicos carregados negativamente (1635 onda.cm-1) e Ãster sulfato (1329,5 e 1260,9 onda.cm-1). Na avaliaÃÃo estrutural da fraÃÃo PII por RMN foi comprovado à presenÃa do grupo Ãster sulfato. Em relaÃÃo Ãs atividades biolÃgicas, o teste de citotoxicidade mostrou que os PT e as fraÃÃes PI e PII nÃo apresentaram toxicidade para a maioria das cÃlulas testadas e nÃo foram eficientes na inibiÃÃo de vÃrus nÃo envelopados Ad-19 e Ad-41. No entanto, os PT e a fraÃÃo PI foram capazes de inibir a infecÃÃo causada por HSV-1 e HSV-2. Em ensaios com metapneumovÃrus (HMPV), a fraÃÃo PII apresentou atividade antiviral superior à ribavirina. Embora os PT e as fraÃÃes PI e PII nÃo terem apresentado atividade contra dengue vÃrus sorotipo 1 (DENV-1), os PT puderam inibir a hemorragia em ratos, diminuindo o tempo de sangramento e o tempo de protrombina. Os PT nÃo apresentaram toxicidade em camundongos, mas aumentaram o tamanho do baÃo e o nÃmero de plaquetas sanguÃneas. Pode ser concluÃdo que extratos foliares de A. barbadensis podem apresentar polissacarÃdeos neutros ou carregados negativamente por grupos carboxilados/sulfatados. Em adiÃÃo, alÃm de apresentar atividade inibitÃria contra os vÃrus HSV-1, HSV-2 e HMPV, podem tambÃm apresentar efeito anti-hemorrÃgico e prÃcoagulante, propriedades essas, importantes, visto que a complicaÃÃo de muitas viroses leva a quadros hemorrÃgicos. AlÃm disso, os PT de A. barbadensis nÃo apresentaram toxicidade expressiva, podendo ser utilizada como agente terapÃutico seguro e eficaz. / The aim of this study was to investigate the physicochemical and structural parameters of polysaccharides obtained from Aloe barbadensis leaves and to evaluate the antiviral and cytotoxic activities and procoagulant, anti-bleeding effects. In addition, toxicological analysis was carried out. The pulp was submitted to aqueous extraction (70 ÂC) and the total polysaccharides (PT) obtained by ethanol precipitation, TCA was used to remove the protein contamination. The fractionation of PT with DEAE-celulose resulted in two fractions (PI and PII). The physicochemical characterization showed that PI fraction presents mannose (78,4%), glucose (7,3%), galactose (2,1%), fucose (2,8%) and uronic acid (10,0%). Sulfate esters were not detected in PI fraction. On the other hand, PII fraction presents the monosaccharides mannose (39,2%), glucose (22,2%), galactose (26,3%), arabinose (3,8%), xylose (1,1%), uronic acids (8,0%) and sulfate esters groups (12,0%). The polysaccharidics of PII obtained by PAGE and agarose gel electrophoresis were revealed with toluidine blue and stainsall dye showing the presence of two different bands, one purple (indicative of sulfate) and another cyan (indicative of carboxilated groups). Structural analysis of PI and PII fractions by IR spectroscopy demonstrated that PI fraction is composed of residues of Ã-mannose O-acetylated (812.2 and 960 cm-1) and uronic acids (1738 cm-1). In contrast, the PII fraction is composed of mannose (1014.7 cm-1), galactose (1078.2 cm-1), negatively charged uronic acids (1635 cm-1) and sulfate ester (1329.5 and 1260.9 cm-1). These results corroborate with NMR analyses that suggest the presence of sulfate groups in PII structure. The cytotoxicity evaluation showed that PT and the fractions PI and PII did not show toxicity against most of tested cells and the same fractions were not effective against non-enveloped virus (Ad 19 and Ad 41) inhibition. However, the PT and PI fraction were able to inhibit the infection caused by HSV-1 and HSV-2. In addition, PII fraction presents antiviral activity against metapneumovirus. Although the PT and the fractions PI and PII did not show activity against dengue virus serotype 1 (DENV-1), PT could inhibit the bleeding effects in rats, reducing the bleeding and prothrombin time. The PT showed no toxicity in mice, but increased spleen size and number of blood platelets. In conclusion, A. barbadensis leaves contain neutral or negatively charged carboxylated/sulfated polysaccharides. In addition, besides having inhibitory activity against HSV-1, HSV-2 and HMPV, they can also anti-bleeding and procoagulant effect. Moreover, the PT of A. barbadensis showed no significant toxicity and can be used as a safe and effective therapeutic agent.
235

Notificação de AIDS no estado da Paraíba: prevalência e fatores associados às manifestações orais local / Notification of AIDS in the State of Paraiba: prevalence and factors associated with oral manifestations

Adriano, Maria Soraya Pereira Franco 31 July 2012 (has links)
Made available in DSpace on 2015-09-25T12:21:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-31 / Oral manifestations may represent the first clinical signs of HIV infection, being indicators of immunological compromise and of the disease progression. Thus, to investigate these expressions is crucial for the understanding of the epidemiology of AIDS. In this study, it was examined the prevalence of oral manifestations reported in patients with AIDS in the State of Paraíba and its associated factors, according to the Information System for Notifiable Diseases / SINAN, from 2000 to 2010. A quantitative cross-sectional epidemiological study was developed, using secondary data collected from the junction of SINAN W and Net from DST/AIDS program of Paraíba, in patients over 13 years old, who had a complete record of their case evolution. The sample census considered the inclusion criteria previously reported. Statistical analysis covered descriptive and analytical techniques, adopting a confidence interval of 95% and Pearson s chi-squared and prevalence ratio tests . The project was approved by the Ethics Committee of the State University of Paraiba, under CAAE 0404.0.133.000-10.For a total of 2.944 reported AIDS cases, occurred the record of 1009 oral manifestations for this disease, being 76.3% of Oral Candidiasis or Hairy Leukoplakia, 20% of Herpes Zoster and 3.7% of Kaposi's sarcoma. It was demonstrated a significant association between Oral Candidiasis or Hairy Leukoplakia and the variables years of research, macro-regions, years of education and evolution of cases, and it was found in the Herpes Zoster association between the variables years of research, age group and cases development (p <0.05 ). The largest number of oral manifestations identified for AIDS was established in the state capital, João Pessoa. According to the obtained results, the notification of oral manifestations of the disease under study has occurred in less than a half of the confirmed cases. / As manifestações orais podem representar os primeiros sinais clínicos da infecção por HIV, sendo indicadoras de comprometimento imunológico e do tempo de evolução da doença. Assim, investigar essas expressões é fundamental para o entendimento da epidemiologia da AIDS. Neste trabalho verificou-se a prevalência de manifestações orais notificadas em portadores de Aids no Estado da Paraíba e seus fatores associados, de acordo com o Sistema de Informação de Agravos de Notificação / SINAN, durante o período de 2000 a 2010. Desenvolveu-se um estudo epidemiológico transversal e quantitativo, utilizando dados secundários coletados a partir da junção do SINAN W e Net do programa do DST/AIDS da Paraíba, em pacientes maiores de 13 anos, que apresentavam o registro completo da evolução do caso. A amostragem censitária considerou os critérios de inclusão anteriormente relatados. O tratamento estatístico abrangeu técnicas descritivas e analíticas, adotando-se um intervalo de confiança de 95% e os testes Qui-quadrado de Person e Razão de Prevalência. O projeto foi aprovado pelo Comitê de Ética em Pesquisa da Universidade Estadual da Paraíba sob CAAE 0404.0.133.000-10. Para um total de 2944 casos notificados de AIDS ocorreu o registro de 1009 manifestações orais para essa doença, sendo 76,3% de Candidose oral ou Leucoplasia Pilosa, 20% de Herpes Zoster e 3,7% de Sarcoma de Kaposi. Demonstrou-se associação significativa entre a Candidose oral ou Leucoplasia Pilosa e as variáveis ano de investigação, macrorregião,grau de escolaridade e evolução dos casos e para o Herpes Zoster encontrou-se associação entre as variáveis ano de investigação, faixa etária e evolução dos casos (p < 0,05). O maior número de manifestações orais identificadas para a Aids ficou estabelecido na capital do Estado, a cidade de João Pessoa. De acordo com os resultados obtidos a notificação de manifestações orais para a doença em questão ocorreu em menos da metade dos casos confirmados da doença.
236

Detecção do herpes simples vírus, citomegalovírus, Epstein-Barr vírus e bactérias periodontopatogênicas em bolsas periodontais de pacientes com periodontite crônica e gengivite / Detection of simplex herpesviruses, Citomegalovirus, Epstein - Barr virus and periodontal pathogens in periodontal pockets of chronic periodontitis and gingivitis patients

Osmar Shizuo Okuda 05 October 2009 (has links)
Recentemente, estudos têm associado a presença de vírus da família herpesviridae à doença periodontal, os quais poderiam estar envolvidos na ocorrência e progressão de diferentes formas da doença periodontal, através da supressão do sistema imune do periodonto, liberação de citotoxinas, mediadores pró-inflamatórios, o que poderia favorecer o crescimento subgengival de microrganismos. Neste estudo, testamos a hipótese de que a prevalência do herpes vírus na placa subgengival de pacientes com gengivite é igual a de pacientes portadores de periodontite crônica. Desse modo, o presente estudo teve como objetivo determinar a presença dos vírus Herpes simples vírus tipo 1 (HSV-1), Citomegalovírus (HCMV) e Epstein-Barr vírus tipo 1 (EBV-1), relacionando-os com a presença de bactérias periodontopatogênicas como: Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf) e Dialister pneumosintes (Dp) em amostras de placa subgengival, coletadas de 30 pacientes portadores de periodontite crônica (grupo PC), 30 pacientes com gengivite (grupo G) e 30 indivíduos periodontalmente saudáveis (grupo C). Foram coletadas quatro amostras de placa subgengival do sítio mais profundo de cada quadrante nos pacientes do grupo PC e nos pacientes do grupo G e C, um sítio aleatório de cada quadrante foi examinado. A detecção de espécies bacterianas e de herpes vírus na placa subgengival dos grupos foi realizada por PCR e Nested PCR, respectivamente. A análise estatística mostrou que o HCMV foi detectado com freqüência similar nos três grupos estudados e que houve uma maior prevalência do HSV-1, EBV-1 e P. intermedia nos pacientes com periodonite crônica e gengivite em relação ao grupo controle. Houve associação da periodontite crônica com o EBV-1 e as cinco bactérias estudadas, além da associação entre os vírus (EBV-1+ HCMV; EBV-1 + HSV-1; HSV-1 + HCMV) e entre vírus e bactérias (EBV-1+ P.intermedia, EBV-1 + P. gingivalis; HCMV + T. forsythia; HCMV + A. actinomycetemcomitans; HSV-1 + T. forsythia; HSV-1 + P. gingivalis). / Recently, studies have linked the presence of the virus family herpesviridae and periodontal disease, which may be involved in the occurrence and progression of different forms of periodontal disease through the suppression of the immune system of the periodontium, release of cytotoxins, pro-inflammatory mediators and immunopathological events, may promote growth of subgingival microorganisms. In this study, we tested the hypothesis that the prevalence of herpes virus in sub-gingival plaque of patients with gingivitis is equal to patients with chronic periodontitis. Thus, this study aimed to determine the presence of the virus Herpes simplex virus type 1 (HSV-1), Cytomegalovirus (HCMV) and Epstein-Barr virus type 1 (EBV-1), relating to the presence of bacteria as periodontopathogens: Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf) and Dialister pneumosintes (Dp) in subgingival plaque samples collected from 30 patients with chronic periodontitis (CP group), 30 patients with gingivitis (group G) and 30 periodontally healthy subjects (group C). We collected four samples of subgingival plaque from the deepest site in each quadrant and in the PC group and patients in group C and G, a random site in each quadrant was examined. The detection of bacterial species and herpes virus in subgingival plaque of the groups were identified by PCR and nested PCR respectively. Statistical analysis showed that HCMV was detected with a similar frequency among the three groups and significant difference in prevalence of HSV-1, EBV-1 and P. intermedia in patients with gingivitis in the control group. The chronic periodontitis was associated with EBV-1 and the five bacteria studied, and the association of the virus (EBV-1 + HCMV, EBV-1 + HSV-1, HSV-1 + HCMV) and between viruses and bacteria (EBV-1+ P.intermedia, EBV-1 + P. gingivalis; HCMV + T. forsythia; HCMV + A. actinomycetemcomitans, HSV-1 + T. forsythia; HSV-1 + P. gingivalis).
237

Gastric erosions – clinical significance and pathology:a long-term follow-up study

Toljamo, K. (Kari) 15 May 2012 (has links)
Abstract Gastric erosions are superficial mucosal breaks. With the exception of bleeding, they are considered harmless, but their aetiology, histopathology and long-term course have remained unknown and even the evolution of gastritis in patients with gastric erosions is unclear. The present study aimed to solve clinical significance and pathology of gastric erosions in a long-term follow-up study. Initially, 117 patients and 117 controls were studied in 1974–1981, and a follow-up study was performed in 1996. We evaluated the presence of Helicobacter pylori and Herpes simplex virus (HSV) infections, use of NSAIDs and alcohol, smoking, and assessed features of gastric histopathology. For follow-up, 52 patients and 66 controls were available. In the follow-up visit, 39% patients still had gastric erosions while 11% of the controls had developed erosions (p&#160;=&#160;0.001). In H. pylori-positive subjects, peptic ulcer or a scar was more common in patients (17%) than in controls (4%, p&#160;=&#160;0.006), but otherwise no increased morbidity or mortality was seen. High antibody titres against HSV predicted the persistence of erosions (p&#160;=&#160;0.000), but H. pylori infection, use of NSAIDs, alcohol or smoking were not associated. Initially, inflammation was more active in the region of erosions than elsewhere in the antral mucosa, and more active inflammation in the erosion was associated with HSV seropositivity, H. pylori infection and the recent use of NSAIDs. Initially, H. pylori-positive subjects with chronic or recurrent erosions had higher scores of neutrophils compared to those with non-chronic/non-recurrent erosions. In H. pylori-positive subjects, body gastritis was initially less active in the patient group. With time, antral gastritis worsened only in the patient group. In H. pylori-negative subjects, there was no evolution of gastritis. These results show that a significant proportion of gastric erosions are chronic/recurrent but mostly without serious complications. However, H. pylori-positive patients have a significant risk to develop a peptic ulcer. A significant proportion of chronic gastric erosions is related to HSV infection. Focally enhanced inflammation modified by HSV or NSAID may be important in the pathogenesis of gastric antral erosions. Active inflammation in the erosions seems to predict their chronicity/recurrency. Patients with erosions share the characteristics of gastritis of the duodenal ulcer phenotype. / Tiivistelmä Eroosiot ovat mahalaukun pinnallisia limakalvovaurioita. Niitä pidetään vaarattomina lukuun ottamatta niihin liittyvää verenvuototaipumusta. Niiden etiologiaa, histopatologiaa ja taudinkulkua ei tunneta. Ei myöskään tiedetä eroosiopotilaiden mahan limakalvon tulehduksen kulkua. Tämän tutkimuksen tavoitteena oli selvittää mahalaukun eroosioiden kliininen merkitys ja patologia pitkäkestoisena seurantatutkimuksena. Alkujaan 117 potilasta ja 117 kontrollihenkilöä tutkittiin vuosina 1974–1981, ja seurantatutkimus tehtiin vuonna 1996. Selvitimme helikobakteerin ja Herpes simplex -viruksen (HSV) aiheuttamien infektioiden, tulehduskipulääkkeiden (NSAID) ja alkoholin käytön, sekä tupakoinnin esiintymistä. Lisäksi tutkimme histopatologisesti mahalaukun limakalvoa. Lopulta oli 52 potilaan ja 66 kontrollihenkilön aineisto käytettävissä. Seurantakäynnillä 39 prosentilla potilaista oli yhä mahalaukun eroosioita, kun taas kontrolliryhmästä vain 11 prosentilla oli kehittynyt eroosioita. Helikobakteeri -infektoituneilla maha- tai pohjukaissuolen haava/arpi oli yleisempää eroosioryhmässä (17&#160;%) kuin kontrolleilla (4&#160;%), mutta muuten ei esiintynyt lisääntynyttä sairastuvuutta tai kuolleisuutta. Tulehdus oli aktiivisempaa eroosioissa kuin viereisellä limakalvolla, ja tämä tulehdus liittyi korkeisiin HSV-vasta-ainetasoihin, helikobakteeri-infektioon ja NSAID:n käyttöön. Korkeat HSV-vasta-ainetasot ennustivat eroosioiden pysyvyyttä. Ensimmäisellä käynnillä aktiivinen tulehdus eroosioissa oli voimakkaampaa niillä helikobakteeri-infektoituneilla, joilla eroosiot olivat pysyviä kuin niillä, joilla eroosiot eivät uusineet. Helikobakteeri-infektoituneilla eroosiopotilailla mahalaukun runko-osan limakalvon tulehdus oli aluksi vähemmän aktiivista kuin vastaavilla kontrolliryhmän henkilöillä, mutta ajan myötä mahalaukun corpusosan limakalvon tulehdus voimistui vain eroosioryhmällä. Limakalvotulehdus ei edennyt helikobakteeri-infektoitumattomilla henkilöillä. Tulokset osoittavat, että merkittävä osa mahalaukun eroosioista on kroonisia/toistuvia, mutta enimmäkseen ilman vakavia komplikaatioita. Kuitenkin helikobakteeri-infektoituneilla eroosiopotilailla on merkittävä riski saada maha- tai pohjakaissuolen haava. HSV- infektio liittyy merkittävään osaan kroonisia mahalaukun eroosioita. Paikallisella tulehdusaktiivisuudella, jota HSV ja NSAID:n käyttö muokkaavat, saattaa olla tärkeä rooli eroosioiden synnyssä ja niiden kroonistumisessa. Eroosiopotilailla on samanlainen mahalaukun limakalvon tulehduksen jakauma kuin pohjakaissuolihaavaa sairastavilla.
238

Modeling neuropathogenesis of B virus infection in the macaque ganglia

LeCher, Julia 09 May 2016 (has links)
B virus is an alphaherpesvirus, endemic to macaque monkeys, capable of deadly human zoonosis with an 80% mortality rate in untreated cases. The macaque monkey is widely used in biomedical research and the threat of B virus poses an occupational hazard to researchers, veterinarians, and animal handlers. B virus establishes a life-long latent infection in sensory neurons of the peripheral nervous system (PNS) in the natural host. In human infections, B virus readily transits to the central nervous system (CNS) and destroys brain tissues. Identifying immune correlates of B virus infection in the PNS of the natural host is critical in understanding viral lethality in the human host. The lack of an accurate animal model and restrictions on handling potentially infected nervous tissue previously limited studies of B virus infection in macaque ganglia. To address this barrier, a long-lived mixed neuron/glia cell culture model was established from macaque DRG explants using a novel methodology that relied on cellular migration from whole tissues. Utilizing this model, the hypothesis tested was that acute B virus infection of macaque ganglia triggers cellular defense networks to promote leukocyte recruitment and impact leukocyte activation. Chemokines were upregulated in B virus-infected cultures and infected cell media induced leukocyte chemotaxis. Leukocytes were less effectively activated by media from infected cells when compared to media from mock-infected cells. To identify factors responsible for this, focused microarrays were performed and cytokine profiles were quantified from B virus and mock-infected culture supernatants. IL-6 protein levels were significantly reduced in B virus infected cultures. This observation led to the hypothesis that IL-6 downregulation impairs leukocyte activation and, indeed, when IL-6 was added to B virus-infected culture supernatants to control levels, these cultures were far more effective at eliciting leukocyte activation when compared with mock-infected cultures. Collectively, these data support the hypothesis that acute B virus infection of macaque ganglia triggers cellular defense networks to promote leukocyte recruitment and impact leukocyte activation and identifies a potential viral mechanism to impair leukocyte functionality. Additionally, this work presents a novel methodology for establishing long-lived mixed neuron/glia cultures from postnatal/adult macaque DRGs.
239

DISCOVERY OF LIGNIN SULFATE AS A POTENT INHIBITOR OF HSV ENTRY INTO CELLS

Thakkar, Jay N 01 January 2006 (has links)
The herpes virus family consists of more than hundred members that infect organisms, of which eight, differing markedly in the biology are known to infect humans. HSV- I is the most common one, causing oral lesions and sporadic encephalitis. These infections are highly prevalent affecting at least one in three individuals in the United States.The entry of the herpes virus into the cell is a two-step process. The initial step involves the cell surface heparan sulfate and glycoproteins in the viral envelope which enables the virus to penetrate into the cell. The second step is the fusion step. Depending on the nature of interaction and size of HS chain, a single chain may bind multiple viral ligands on a virion. There is substantial evidence showing that HS plays an important role in viral binding.HS is a heterogeneous, linear sulfated oligosaccharide composed of alternating glucosamine and uronic acid residues, which could specify distinct receptor for various viral ligands. HS, present on most exposed cell surfaces, make an ideal snare for the capture of most herpes viruses and may facilitate subsequent interactions with other co-receptors required for entry. Number of viruses, including HSV- I, HSV- II, HIV- I and dengue virus use sites of HS as receptors for binding to cells. Recently 2000 Liu et.al have characterized a HS based octasaccharide that binds to HSV-I gD. The distinguished feature in the composition of the octasaccharide is the presence of 3-O-sulfate glucosamine residue, which is an uncommon structural modification in HS. Its presence in the HSV-I gD binding sequence may confer specificity of interaction and assist HSV-I entry into the cell.Numerous sulfated molecules have been explored as mimics of HS in the inhibition of HSV-1 entry into cells. To date, most of the sulfated molecules screened for anti-viral activity have been carbohydrates. So, we reasoned that it should be possible to mimic critical interactions of HS with one or more viral glycoprotein using synthetic, non-polysaccharide, sulfated compounds. Further, it may be possible to mimic specific sequence(s) in HS, which play a role in HSV infection, with small synthetic, sulfated, non-carbohydrate molecules. In a search for synthetic mimics of HS as inhibitors of HSV-I infection, we screened a small, synthetic, sulfated flavonoids to discover a potent inhibitory activity arising from sulfation of a macromolecule present as an impurity in a crude natural product.The active principle was identified through an array of biophysical and chemical analyses as lignin sulfate, a heterogeneous; polydisperse network polymer composed of substituted phenylpropanoid monomers. Further, LC-MS with APCI in negative ionization mode, which have been reported in here for the first time for analysis of lignin, has been successfully used to deduce oligomeric structures present in the precursor of the active macromolecule based on the spectrum of the depolymerized lignin. This corroborates well with the structural information obtained using other analytical techniques. We hypothesize that the structural heterogeneity and polydispersity of lignin coupled with optimal combination of sulfate charge and hydrophobicity result in high potency. Given that the native lignin is inactive, lignin sulfate discovered here provides a variety of organic scaffolds that with the critical sulfate groups in space can mimic the HSV-I gD binding sequence.
240

Viral subversion of host cell membrane trafficking

Muenzner, Julia January 2017 (has links)
Enveloped viruses acquire their membrane coat from the plasma membrane or intracellular organelles and rely on cellular machinery to facilitate envelopment and egress of virus progeny. This thesis examines egress-related interactions between host cell factors and proteins of two different enveloped viruses: hepatitis D virus (HDV) and herpes simplex virus 1 (HSV-1). HDV is a small RNA virus causing fulminant hepatitis or severely aggravating cirrhosis and hepatocellular carcinoma. HSV-1 is a large DNA virus infecting epithelial and neuronal cells. Infection with HSV-1 not only triggers the development of recurring sores on oral or genital mucosa, but can also cause severe disease in neonates and immunocompromised patients. The interaction between the large antigen of HDV (HDAg-L) and the N-terminal domain (NTD) of clathrin, a protein crucial for endocytosis and intracellular vesicular trafficking, was examined by structural, biochemical and biophysical techniques. Co-crystal structures of NTD bound to HDAg-L peptides derived from different HDV genotypes revealed that HDV interacts with multiple binding sites on NTD promiscuously, prompting re-evaluation of the binding between cellular peptides and NTD. Surprisingly, co-crystal structures and pull-down capture assays showed that cellular peptides containing clathrin-binding motifs can also bind multiple sites on the surface of NTD simultaneously. In addition, the structures of viral and cellular peptides bound to NTD enabled the molecular characterization of the fourth peptide binding site on NTD, the “Royle box”, and led to the identification of a novel binding mode at the “arrestin box” peptide binding site on NTD. The work in this thesis therefore not only identifies the molecular basis of HDV:clathrin interactions, but also furthers our understanding of basic clathrin biology. Even though many HSV-1 proteins have been implicated in the envelopment and egress of viral particles, only few interactions between HSV-1 and cellular proteins promoting these processes have been described. Therefore, the HSV-1 proteins gE, UL21 and UL56 were selected and characterized bioinformatically and/or biochemically. Cellular proteins interacting with UL56 were identified by yeast two-hybrid screening and quantitative mass spectrometry. Co-immunoprecipitation and pull-down experiments confirmed the Golgi-trafficking protein GOPC, components of the mammalian trafficking protein particle complex, and the ubiquitin ligase NEDD4 as novel binding partners of UL56, thereby suggesting exciting new avenues for the investigation of cellular mechanisms contributing to HSV-1 envelopment and egress.

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