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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.
81

Correla??o entre a infec??o genital pelo v?rus do papiloma humano, a resposta imune e os achados colpocitol?gicos em mulheres gr?vidas e n?o gr?vidas

Lima, ?rika Galv?o de 20 December 2012 (has links)
Made available in DSpace on 2014-12-17T14:10:28Z (GMT). No. of bitstreams: 1 ErikaGL_DISSERT.pdf: 2372644 bytes, checksum: 71509c6c298fb6e35890d8d13548037c (MD5) Previous issue date: 2012-12-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The genital HPV infection is very common between men and women worldwide, affecting particularly young women, constituting a serious public health problem in less developed regions, favored by the poor living conditions of population. The cytology and colposcopy have notorious importance in the diagnosis of precursor lesions of cervical cancer and therefore its prevention. However, even with such diagnostic tools, the number of women who develop cervical cancer is still high. This study aims to assess the prevalence of genital tract infection by HPV in pregnant and nonpregnant women, evaluating the profile of the immune response presented by the women of these two groups in order to establish correlations among profile of immune response, presence of virus and occurrence of lesions of the uterine cervix. We analyzed specimens obtained from the cervix of 221 patients, 91 pregnant and 130 non-pregnant, aged 14-72 years. The women were subjected to colposcopic and cytologic evaluation detect possible changes in the cervix and then samples were collected in order to perform HPV detection by PCR and real-time PCR for detection of mRNA of pro-inflammatory and anti-inflammatory cytokines. In the present study, the overall prevalence of HPV genital infection was 28.1%; of which 31.9% were pregnant patients and 25.4% in non-pregnant women. Young women under 30 years and those with low educational level education showed a higher risk of HPV infection. Colposcopy showed better correlation with detection of HPV DNA by PCR, when compared to cytology. Generally, HPV infected patients, pregnant or not, exhibited reduced mRNA expression of both pro-inflammatory (IFN-γ, TNF-α) and anti-inflammatory (IL -10) cytokines, when compared to patients not infected by HPV. Nonpregnant patients infected presented increase mRNA expression of IL-17 in patients without injury, whereas those with lesion showed higher mRNA expression of TGF-β. Pregnant women without injury infected exhibited increased mRNA expression of TGF-β. There was no difference in HPV prevalence between pregnant and nonpregnant women. There was a reduction of pro-inflammatory cytokines, except IL-17, in all women infected by HPV. Moreover, we observed an increase of TGF-β in HPV-infected women who are pregnant or not. The results suggest that, in women in this study, HPV infection promoted changes in the profile of cytokines necessary for activation of effective immune response, possibly favoring viral persistence / A infec??o genital pelo v?rus do papiloma humano (HPV) ? muito frequente entre homens e mulheres em todo o mundo, afetando em especial mulheres jovens, constituindo-se em grave problema de sa?de p?blica nas regi?es menos desenvolvidas, sendo favorecida pelas condi??es prec?rias de vida da popula??o. A citologia onc?tica e a colposcopia t?m not?ria import?ncia no diagn?stico das les?es precursoras do c?ncer do colo uterino e, portanto, na sua preven??o. No entanto, mesmo com a disponibilidade dessas ferramentas diagn?sticas o n?mero de mulheres que desenvolvem c?ncer do colo do ?tero ainda ? elevado. Esse estudo tem por objetivo avaliar a preval?ncia de infec??o do trato genital por HPV, em mulheres gr?vidas e n?o gr?vidas, avaliando o perfil da resposta imune apresentado pelas mulheres desses dois grupos, visando estabelecer correla??es entre o perfil de resposta imune, a presen?a do v?rus e ocorr?ncia de les?es da c?rvice uterina. Foram inclu?das neste estudo 221 pacientes, sendo 91 gr?vidas e 130 n?o gr?vidas, com idade variando de 14 a 72 anos. As mulheres foram submetidas a uma avalia??o colpocitol?gica para a detec??o de poss?veis altera??es na c?rvice uterina e em seguida coletados esp?cimes para an?lise por meio da rea??o em cadeia da polimerase (PCR) convencional para detec??o do HPV e PCR em tempo real para detec??o de RNA mensageiro (RNA-m) de citocinas pr?-inflamat?rias e anti-inflamat?rias. A preval?ncia global da infec??o genital pelo HPV, encontrada neste estudo, foi de 28,1%, sendo 31,9% em pacientes gr?vidas e 25,4% nas n?o gr?vidas. As mulheres jovens com at? 30 anos e aquelas com baixa escolaridade apresentaram maior risco de ter infec??o pelo HPV. A colposcopia apresentou melhor correla??o com a detec??o do DNA do HPV por PCR, quando comparada ? citologia. De um modo geral, as pacientes infectadas pelo HPV, gr?vidas ou n?o, apresentaram uma redu??o da express?o de RNA-m tanto para as citocinas pr?-inflamat?rias (IFN-γ, TNF-α), quanto para a citocina anti-inflamat?ria (IL-10) em rela??o ?s pacientes n?o infectadas com HPV. Nas pacientes n?o gr?vidas e infectadas, a express?o do RNA-m para IL-17 mostrou-se aumentada nas pacientes sem les?es, enquanto que, aquelas com les?o apresentaram maior express?o do RNA-m para TGF-β. As mulheres gr?vidas e infectadas pelo HPV e sem les?o, apresentaram aumento na express?o do RNA-m para TGF-β. N?o houve diferen?a de preval?ncia do HPV entre mulheres gr?vidas e n?o gr?vidas. Observou-se uma redu??o da produ??o de citocinas pr?-inflamat?rias, exceto IL-17, em todas as mulheres infectadas pelo HPV, e um aumento de TGF-β, nas mulheres infectadas pelo HPV gr?vidas ou n?o. Os resultados sugerem que, nas mulheres deste estudo, a infec??o pelo HPV promoveu uma altera??o no perfil de citocinas necess?rias para a ativa??o de uma resposta imune efetiva, possivelmente favorecendo a persist?ncia viral
82

Preval?ncia da infec??o por Chlamydia Trachomatis em mulheres atendidas no Programa de rastreamento do c?ncer de colo do ?tero

Magalh?es, Paulo Andr? Freire 08 August 2013 (has links)
Made available in DSpace on 2014-12-17T14:10:29Z (GMT). No. of bitstreams: 1 PauloAFM_DISSERT.pdf: 770018 bytes, checksum: c4b92c68824123455aa7a5f94bd77119 (MD5) Previous issue date: 2013-08-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Genital infection with Chlamydia trachomatis is now recognized as one of the most prevalent sexually transmitted infections (STDs). Despite major advances in laboratory diagnosis techniques, primarily the character of asymptomatic chlamydial infection in both men and in women constitutes the basis for the formation of reservoirs that perpetuate transmission and acquisition of this and other STDs. The asymptomatic in women favors the rise of infection to the upper genital tract, causing injuries that can result in infertility. An examination of population screening for early detection and treatment of asymptomatic infections is the key step in combating this major public health problem. The present study aimed to evaluate the prevalence of infection by C. trachomatis in sexually active women attended the screening program for cervical cancer of the uterus in health facilities in municipalities in different regions of the State of Rio Grande do Norte, and identify factors that may contribute to the spread of this pathogen and its relationship with the lesions of the uterine cervix. It is a cross-sectional study aimed at detecting the presence of genital tract infection by C. trachomatis either in isolated form or in association with human papilloma virus (HPV) infection in asymptomatic women. Were included in this study, a total sample of 1,134 women aged 13-76, mean 34.4 years, from March 2008 to September 2012. Specimens containing exfoliated cells of the epithelium of the uterine cervix were analyzed by examining Pap cytology for the detection of possible injuries, and the polymerase chain reaction (PCR) for detection of plasmid DNA from C. trachomatis and HPV. Infection with C. trachomatis was detected with overall prevalence rate of 8.1% in the isolated form and 2.8% in co-infection with HPV. The infection was detected in 7.4% of women with normal cytology 11.5% of those with atypical cells of undetermined significance (ASC-US) and 16.7% of those with low-grade squamous intraepithelial lesion (LSIL). We observed an association between C. trachomatis and incidence of low-grade squamous intraepithelial lesion (LSIL). The genital tract infection by C. trachomatis alone was associated with education level, ethnicity and parity, revealing that women with higher education, those of non-white ethnicity and those who had three or more pregnancies were more likely to acquire infection. Levels very close to statistical significance were observed for chronological age, age at first sexual intercourse and first pregnancy. There was no association with marital status, number of sexual partners. Co-infection with C. trachomatis and HPV was detected in 2.3% of women with normal cytology, who had 5.1% in ASC-US and 10.4% in those with LSIL. No association was found between infection C. trachomatis and increased risk of HPV infection, but women with simultaneous infection by both pathogens showed greater risk for LSIL. Co-infection was more prevalent among single women, who had in the first sexual intercourse under 18 years and those who had two or more sexual partners over a lifetime / A infec??o genital por Chlamydia trachomatis ? reconhecida atualmente como uma das mais prevalentes infec??es sexualmente transmiss?veis (IST). Apesar dos grandes avan?os das t?cnicas de diagn?stico laboratorial, o car?ter primariamente assintom?tico da infec??o clamidial tanto em homens, quanto em mulheres constitui-se na base para forma??o de reservat?rios que perpetuam a transmiss?o e a aquisi??o desta e de outras IST. A forma assintom?tica em mulheres favorece a ascens?o da infec??o para o trato genital superior, ocasionando agravos que podem resultar em infertilidade. O exame de triagem populacional para a detec??o precoce e o tratamento das infec??es assintom?ticas ? o procedimento chave no combate a este importante problema de sa?de p?blica. O presente estudo teve como objetivo avaliar a preval?ncia da infec??o por C. trachomatis em mulheres sexualmente ativas atendidas pelo programa de rastreamento do c?ncer de colo do ?tero em unidades de sa?de de munic?pios das diferentes regi?es do Estado do Rio Grande do Norte, bem como identificar fatores que podem contribuir para a dissemina??o desse pat?geno e sua rela??o com as les?es da c?rvice uterina. Trata-se de um estudo transversal que visa detectar a presen?a de infec??o do trato genital por C. trachomatis seja na forma isolada, ou em associa??o com o v?rus do papiloma humano (HPV) em mulheres assintom?ticas. Foram estudadas 1.134 mulheres com idade variando de 13 a 76, m?dia de 34,4 anos, no per?odo de mar?o de 2008 a setembro de 2012. Esp?cimes contendo c?lulas descamadas do epit?lio da c?rvice uterina foram analisados por meio do exame citol?gico de Papanicolau para a detec??o de poss?veis les?es, e pela rea??o em cadeia da polimerase (PCR) para detec??o do DNA plasmidial da C. trachomatis e do HPV. A infec??o por C. trachomatis foi detectada com taxa de preval?ncia global de 8,1%, na forma isolada e de 2,8% em co-infec??o com HPV. A infec??o foi detectada em 7,4% das mulheres com citologia normal, 11,3% daquelas com c?lulas at?picas de significado indeterminado (ASC-US) e 16,7% das que tinham les?o intraepitelial de baixo grau (LSIL). Observou-se associa??o entre C. trachomatis e ocorr?ncia de les?o intraepitelial de baixo grau (LSIL). A infec??o do trato genital por C. trachomatis sozinha mostrou-se associada com escolaridade, etnia e n?mero de gesta??es, revelando que as mulheres com maior escolaridade, as de etnia n?o branca e aquelas que tiveram tr?s ou mais gesta??es apresentaram maiores chances de adquirir infec??o. N?veis muito pr?ximos da signific?ncia estat?stica foram observados, para idade cronol?gica, idade do primeiro intercurso sexual e da primeira gesta??o. N?o se observou associa??o com situa??o conjugal e n?mero de parceiros sexuais. A co-infec??o por C. trachomatis e HPV foi detectada em 2,3% das mulheres com citologia normal, 5,1% nas que tinham ASC-US e 10,4% naquelas com LSIL. N?o se observou associa??o entre a infec??o C. trachomatis e aumento de risco de infec??o pelo HPV, mas as mulheres com infec??o simult?nea pelos dois pat?genos apresentaram maior risco de ter LSIL. A co-infec??o foi mais prevalente nas mulheres solteiras, nas que tiveram o primeiro intercurso sexual com menos de 18 anos e nas que tiveram dois ou mais parceiros sexuais ao longo da vida
83

Caracteriza??o gen?tica do v?rus Chikungunya circulante no Estado do Rio Grande do Norte

Pereira, Hannaly Wana Bezerra 27 February 2018 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-04-03T14:48:30Z No. of bitstreams: 1 HannalyWanaBezerraPereira_DISSERT.pdf: 2518932 bytes, checksum: 2d0f7247523a10a3475dd41f16e8f017 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-04-10T20:00:29Z (GMT) No. of bitstreams: 1 HannalyWanaBezerraPereira_DISSERT.pdf: 2518932 bytes, checksum: 2d0f7247523a10a3475dd41f16e8f017 (MD5) / Made available in DSpace on 2018-04-10T20:00:29Z (GMT). No. of bitstreams: 1 HannalyWanaBezerraPereira_DISSERT.pdf: 2518932 bytes, checksum: 2d0f7247523a10a3475dd41f16e8f017 (MD5) Previous issue date: 2018-02-27 / A febre Chikungunya ? uma s?ndrome febril com grave artralgia debilitante, podendo evoluir para casos at?picos, como manifesta??es neurol?gicas e mucocut?neas. Geralmente ? transmitida por mosquitos do g?nero Aedes. O agente etiol?gico ? o v?rus Chikungunya (CHIKV) que pertence ? fam?lia Togaviridae e ao g?nero Alphavirus. At? pouco tempo essa doen?a era negligenciada no Brasil, por?m com o surto epid?mico que houve no ano de 2016, essa arbovirose se tornou um desafio para a sa?de p?blica. O objetivo do presente estudo foi realizar a caracteriza??o gen?tica do CHIKV identificado no Estado do Rio Grande do Norte (RN), no bi?nio 2016-2017. Um total de 10 amostras de soro, l?quor ou conte?do de ves?culas-bolhosas foram analisadas pela metodologia de qRT-PCR para detec??o do CHIKV e todas se apresentaram positivas. Foi realizada a filogenia e a caracteriza??o gen?tica do v?rus, por meio do sequenciamento da regi?o codificadora da poliprote?na estrutural, com posterior an?lise da estrutura da prote?na por meio da modelagem. A an?lise filogen?tica indicou que o gen?tipo circulante no Estado do Rio Grande do Norte ? o Leste-Centro-Sul Africano II (ECSA II). A compara??o entre as sequencias dos CHIKV deste estudo com aquelas de seu ancestral da linhagem ECSA II identificado em Uganda em 1982 (GenBank: HM045812) revelou a presen?a de 21 muta??es n?o sin?nimas. O sequenciamento dos CHIKV do soro e do l?quor de um mesmo paciente revelou duas muta??es n?o sin?nimas potencialmente associadas a neurovirul?ncia viral: N606K e P677L. Adicionalmente, a an?lise da modelagem de prote?nas mostrou que o v?rus circulante no Rio Grande do Norte n?o apresenta a muta??o na posi??o A226V, que determina uma maior infectividade do v?rus para o Aedes albopictus. Em conclus?o, esse estudo revela a origem do CHIKV circulante no Estado do Rio Grande do Norte e poss?veis marcadores de neurovirul?ncia viral, informa??es ?teis para compreender a evolu??o viral e a patog?nese da doen?a. / Chikungunya fever is a febrile syndrome with severe debilitating arthralgia, which may progress to atypical cases, such as neurological and mucocutaneous manifestations. It is usually transmitted by mosquitoes of the genus Aedes. The etiological agent is the Chikungunya virus (CHIKV) that belongs to the family Togaviridae and to the genus Alphavirus. Until recently this disease was neglected in Brazil, but with the epidemic outbreak that occurred in the year 2016, this arbovirose has become a challenge for public health. The objective of the present study was to perform the genetic characterization of the CHIKV identified in the State of Rio Grande do Norte (RN), in the biennium 2016-2017. A total of 10 serum samples, cerebrospinal fluid (CSF) or blister samples were analyzed by the qRT-PCR methodology for CHIKV detection and all were positive. Phylogeny and genetic characterization of the virus were performed by sequencing the coding region of the structural polyprotein, with subsequent analysis of the protein structure through modeling. Phylogenetic analysis indicated that the circulating genotype in the State of Rio Grande do Norte is East-Central-South-African II (ECSA II). The comparison between CHIKV sequenced in this study and its ancestor from ECSA II lineage identified in Uganda in 1982 (GenBank: HM045812) revealed the presence of 21 non-synonymous mutations. Sequencing of serum and CSF CHIKV from the same patient revealed two non-synonymous mutations potentially associated with viral neurovirulence: N606K and P677L. In addition, the analysis of the protein model showed the circulating non-RN virus has no mutation at position A226V which is the major part of virus infection for Aedes albopictus. In conclusion, this study reveals the origin of CHIKV circulating in the State of Rio Grande do Norte and possible markers of viral neurovirulence, useful information to understand the viral evolution and the pathogenesis of the disease.
84

Avalia??o da atividade antiviral de extratos obtidos da folha e fruto de Morinda citrifolia contra o v?rus dengue

Moreira, Polyanna Silva 23 February 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-05T21:41:06Z No. of bitstreams: 1 PolyannaSilvaMoreira_DISSERT.pdf: 1108101 bytes, checksum: 99f0f4dcef670d145f1ddf9eb582a862 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-18T21:33:56Z (GMT) No. of bitstreams: 1 PolyannaSilvaMoreira_DISSERT.pdf: 1108101 bytes, checksum: 99f0f4dcef670d145f1ddf9eb582a862 (MD5) / Made available in DSpace on 2017-09-18T21:33:56Z (GMT). No. of bitstreams: 1 PolyannaSilvaMoreira_DISSERT.pdf: 1108101 bytes, checksum: 99f0f4dcef670d145f1ddf9eb582a862 (MD5) Previous issue date: 2017-02-23 / A dengue ? uma arbovirose que afeta o homem, gerando uma problem?tica na sa?de p?blica do mundo, especialmente em pa?ses tropicais os quais apresentam condi??es que favorecem a dissemina??o do mosquito Aedes aegypti. Atualmente, dentre as v?rias estrat?gias para controle da doen?a, ainda n?o se tem uma vacina eficaz ou um antiviral capaz de combater essa infec??o. Assim, o objetivo do presente estudo foi avaliar a atividade antiviral de extratos obtidos da folha e frutos da planta Morinda citrifolia L. em cultura de c?lulas Vero infectadas com v?rus dengue-2 (DENV-2). Inicialmente foram obtidos os extratos brutos (hidroetan?lico) e as respectivas fra??es: hexano, clorof?rmio e acetato de etila, analisados por cromatografia. O teste de citotoxicidade do extrato bruto, res?duo aquoso e fra??es foram realizados em cultura de c?lulas Vero pelo m?todo MTT, nas concentra??es de 1000; 500; 250; 125; 62,5; 31,2 ?g/mL. O ensaio antiviral foi conduzido atrav?s das seguintes estrat?gias: c?lulas infectadas com DENV-2 (controle positivo); c?lulas mantidas com meio de cultura (controle negativo); c?lulas infectadas com DENV-2 e tratadas com o extrato ou fra??es. Ap?s cinco dias de infec??o a viabilidade celular foi avaliada pelo m?todo de MTT e o sobrenadante da cultura foi utilizado para quantifica??o viral por unidade formadora de placa (PFU). Os resultados demonstraram que a an?lise cromatogr?fica dos extratos e fra??es revelou bandas distintas e sugestivas de saponinas, terpenos e flavonoides. Tais extratos e fra??es n?o foram t?xicos para as culturas de c?lulas, com exce??o do tratamento das c?lulas com a fra??o clorof?rmio obtido da folha e as fra??es hexano e acetato de etila do fruto verde, levando a uma viabilidade pr?xima de 65%. No ensaio antiviral o controle positivo apresentou viabilidade celular em torno de 60% ap?s cinco dias de infec??o. No tratamento com os compostos obtidos da folha observou-se que ao adicionar a fra??o de acetato de etila ?s c?lulas infectadas, estas mantiveram uma viabilidade celular pr?ximo a 100% na concentra??o de 1000?g/mL e a 85% nas concentra??es de 500 e 250?g/mL. O tratamento com a fra??o hexano apresentou uma viabilidade superior ao controle positivo em todas as concentra??es. No entanto, na fra??o clorof?rmio, a viabilidade manteve-se elevada apenas nas concentra??es de 500 e 250?g/mL. O extrato bruto e a fra??o residual aquosa n?o demonstraram atividade antiviral. As c?lulas tratadas com o extrato e as diferentes fra??es obtidas dos frutos maduro e verde, apresentaram de um modo geral uma viabilidade celular pr?xima de 100% nas concentra??es de 500 e 1000 ?g/mL no fruto maduro e apenas 1000 ?g/mL no fruto verde, com exce??o das c?lulas que foram tratadas com a fra??o clorof?rmio, na qual n?o foi poss?vel observar nenhuma diferen?a significativa quando comparado ao controle positivo. Na quantifica??o viral observou-se que as c?lulas tratadas com as fra??es hexano e clorof?rmio obtidos da folha e tamb?m os extratos brutos obtidos dos frutos maduro e verde tiveram a??o antiviral, resultando na diminui??o total da carga viral. Finalmente, a partir desse estudo podemos identificar uma poss?vel atividade antiviral dos compostos obtidos de Morinda citrifolia contra o v?rus dengue. / Dengue is an arbovirosis which affects mankind, causing problems in the public health worldwide, especially in tropical countries which present conditions that favor the spread of the mosquito Aedes aegypti. Currently, among the various strategies to control the disease, there is no effective vaccine or antiviral capable of combating this infection. Thus, the aim of the present study was to evaluate the antiviral activity of leaf and fruit extracts of the plant Morinda citrifolia L. in Vero cells culture infected with dengue-2 virus (DENV-2). Initially, the crude extracts (hydroethanolic) and their fractions were obtained: hexane, chloroform and ethyl acetate, followed by chromatographic analysis. The cytotoxicity test of the crude extract, the aqueous residue and its fractions were performed in culture of Vero cells by the MTT method, at concentrations of 1000; 500; 250; 125; 62.5; 31.2 ?g/mL. The antiviral assay results were conducted through the following strategies: cells infected with DENV-2 (positive control); cells maintained with culture medium (negative control); cells infected with DENV-2 and treated with the extract or fractions. After five days of infection, cell viability was evaluated by the MTT method and culture supernatant was used for viral quantification by plaque forming unit (PFU) assay. The results showed that the chromatographic analysis of extracts and fractions present distinct bands, which could be suggestive of saponins, terpenes and flavonoids. Such extracts and fractions were not toxic to cell cultures, except for the cells treated with the chloroform fraction obtained from leaf, hexane and ethyl acetate fractions of the green fruit, leading to a near 65% viability. In the antiviral assay the positive control had 60% of cell viability after five days of infection. Among the leaf extract treatments, it was observed that infected cells treated with ethyl acetate fraction, maintained their cell viability around 100% in the concentration of 1000?g/mL and up to 85% in the concentrations of 500 and 250?g/mL. The hexane fraction treatment showed higher viability in comparison to the positive control at all concentrations. However, in the chloroform fraction, viability remained high only at concentrations of 500 and 250 ?g/mL. Crude extract and residual aqueous fraction did not show any antiviral activity. Cells treated with the extract and different fractions obtained from the mature and green fruits, presented an overall cell viability close to 100% in 500 and 1000 ?g/mL in the mature fruit and only 1000 ?g/mL in the green fruit. However, for the cells treated with the chloroform fraction, it was not possible to observe any significant difference when compared to the positive control. In the viral quantification it was observed that cells treated with hexane and chloroform fractions obtained from leaf, as well as crude extracts obtained from mature and green fruits had antiviral effect, resulting in a total viral load decrease. Finally, identified from this study, a possible antiviral activity of the compounds obtained from Morinda citrifolia against dengue virus.
85

Vacina??o com pept?deo M209-223 do v?rus sincicial respirat?rio (VSR) promove uma resposta imune protetora contra infec??o e reduz a inflama??o no pulm?o / Vaccination with respiratory syncytial virus (RSV) M209-223 peptide promotes a protective immune response against infection and reduces lung inflammation

Fazolo, Tiago 20 March 2017 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-02-16T19:08:17Z No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-02-22T17:20:04Z (GMT) No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) / Made available in DSpace on 2018-02-22T17:35:15Z (GMT). No. of bitstreams: 1 Tese Vers?o Final Tiago Fazolo 18_01_2018.pdf: 3827531 bytes, checksum: b081e8333d16cb49ba00d0df25dff485 (MD5) Previous issue date: 2017-03-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Respiratory syncytial virus (RSV) is the most common etiologic agent in severe lower respiratory tract infections (LRTI) in children. RSV-associated LRTI is the main cause of bronchiolitis, pneumonia and exacerbation of asthma. This infection is responsible for the high rates of hospitalizations related to respiratory diseases worldwide, especially in children younger than 2 years. Currently, annual mortality rate due to RSV infections is worrying worldwide and is estimated at approximately two hundred thousand cases. The treatment strategies to RSV infections are limited. Ribavirin is an approved drug for use in RSV infections, but its use is limited due to adverse side-effects and risks posed to health professionals who handle it. Palivizumab is a monoclonal antibody which targets RSV F glycoprotein and its use is only indicated as a prophylactic measure. This treatment is already accepted in several countries for groups of high risk children (premature children, with chronic lung disease and with congenital heart disease). However, palivizumab has a high cost for public health and is not available in all countries. The development of an effective RSV vaccine to generate a long-lasting immunological memory response that prevents infection may be the best alternative because it will reduce high public health expenditures with antiviral drugs and monoclonal antibodies. The first attempt in the search for a vaccine against RSV was in the 1960s. This vaccine produced high levels of serum antibodies but could not protect against infection. Children who were vaccinated developed a more serious disease when later infected with the same virus. To date, there is no licensed vaccine for RSV, so the search for effective vaccines is an important focus of research. Natural RSV infections do not induce lasting protective memory, and multiple reinfections can occur lifetime. Nasal secretions from infected infants presented a small number of regulatory CD4 T cells (Treg) in peripheral blood, an increase in interleukin 4 (IL-4) production and T helper type 2 (Th2) response. Treg cells are important for controlling an exacerbated increase in immune responses. A reduction of the Tregs caused by the RSV infection generates an exacerbation of the pulmonary disease due to a Th2 response. The M209-223 RSV peptide was identified to increase IFN-? production by peptide-specific CD4 T cells after challenge with the virus. The treatment with this peptide also induced an increase in pulmonary Treg frequency in infected mice. Recently, it has also been shown that Tregs aid in the development of a T CD8+ effector response, which is crucial for the control of RSV viral load. Our hypothesis is that the RSV M209-223 peptide impacts in the differentiation of CD4 T cells, increasing the population of specific Treg, reducing lung inflammation and modulating the anti-RSV immune response. This peptide in animal model induces the differentiation of specific Treg. Our findings suggest that vaccination with M209-223 peptide results in the differentiation of specific CD4 T cells into conventional effectors and Treg cells. Vaccination with this peptide decreased the expansion of a Th2 response in animals infected with RSV, protecting both the infection site and systemically. We believe that this approach could be an important component in vaccination strategies against this virus. / O v?rus sincicial respirat?rio (VSR) ? o agente etiol?gico mais comum nas infec??es graves do trato respirat?rio inferior (TRI) em crian?as. As infec??es do TRI associada com o VSR s?o a principal causa de bronquiolite, pneumonia e exacerba??o da asma. As TRI causadas pelo VSR s?o respons?veis pelas altas taxas das hospitaliza??es relacionadas ?s doen?as respirat?rias em todo o mundo, principalmente em crian?as menores de dois anos. Atualmente a taxa de mortalidade anual mundial devido ?s infec??es pelo VSR ? preocupante e ? estimada em aproximadamente duzentas mil crian?as. As estrat?gias de tratamento contra o VSR utilizadas s?o limitadas. A ribavirina ? um f?rmaco aprovado no uso para infec??es pelo VSR, por?m sua utiliza??o ? limitada devido aos efeitos secund?rios adversos e aos riscos que representam para os profissionais da sa?de que o manipulam. O palivizumabe ? um anticorpo monoclonal dirigido contra a glicoprote?na F do v?rus e sua utiliza??o ? apenas como medida profil?tica. Este tratamento j? ? aceito em v?rios pa?ses nos grupos de crian?as de alto risco (crian?as prematuras, com doen?a pulmonar cr?nica e com cardiopatia cong?nita). Entretanto o palivizumabe tem um alto custo para sa?de p?blica, n?o sendo disponibilizado em todos os pa?ses. O desenvolvimento de uma vacina eficaz contra o VSR pode ser a melhor alternativa, pois ao gerar resposta de mem?ria duradoura que previne a infec??o e reduz, desta forma, os altos gastos com a sa?de p?blica, com os f?rmacos antivirais e com os anticorpos monoclonais. A primeira tentativa na busca de uma vacina contra o VSR foi na d?cada de 60. A vacina produzida estimulou n?veis moderadamente elevados de anticorpos no soro, mas n?o conseguiu proteger contra ? infec??o. As crian?as que foram vacinadas desenvolveram uma doen?a mais grave quando mais tarde infectados com o v?rus. At? o presente momento n?o existe nenhuma vacina licenciada para o VSR. Desta forma, a busca de vacinas eficazes constitui um importante foco de pesquisa em todo mundo. As infec??es naturais pelo VSR n?o induzem mem?ria protetora duradoura, ocorrendo m?ltiplas reinfec??es ao longo da vida. Em crian?as infectadas, observou-se um n?mero reduzido de c?lulas T CD4+ regulat?rias (Treg) no sangue perif?rico, um aumento na produ??o de interleucina 4 (IL-4) e uma resposta T helper do tipo 2 (Th2) nas secre??es nasais. As c?lulas Treg s?o importantes para controlar um aumento exagerado da resposta imunol?gica. Por este fato acredita-se que quando h? uma redu??o das Tregs causada pela infec??o do VSR ocorre uma exacerba??o da doen?a pulmonar devido uma resposta Th2. Foi identificado que o pept?deo M209-223 do VSR aumenta a produ??o de IFN-? nas c?lulas T CD4+ ap?s o desafio com VSR. O tratamento com este mesmo pept?deo tamb?m apresentou um aumento na frequencia de c?lulas Treg ap?s infec??o prim?ria pelo VSR. Recentemente tamb?m foi demonstrado que as Tregs auxiliam no desenvolvimento de uma resposta efetora T CD8+, que ? crucial para o controle da carga viral do VSR. Nossa hip?tese ? que o pept?deo M209-223 do VSR influencia na diferencia??o das c?lulas T CD4+, aumentando a popula??o de c?lulas T efetoras e regulat?rias espec?ficas, reduzindo a inflama??o pulmonar e modulando a resposta imune. Os nossos resultados sugerem que a vacina??o com pept?deo M209-223 resulta na diferencia??o de c?lulas T CD4+ espec?ficas em efetoras convencionais, que produzem mais IFN-? e em c?lulas Treg. A vacina??o com este pept?deo diminuiu a expans?o de uma resposta Th2 nos animais infectados com o VSR, protegendo da inflama??o exacerbada tanto no local da infec??o como sistemicamente. Acreditamos que esta abordagem pode constituir um componente importante nas estrat?gias de vacina??o contra este v?rus.
86

O v?rus sincicial respirat?rio induz NETose cl?ssica ROS-dependente atrav?s da ativa??o de PAD4 e das vias de necroptose

Muraro, Stefanie Primon 16 March 2018 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-05-21T13:12:10Z No. of bitstreams: 1 Vers?o completa da disserta??o-stefaniemuraro.pdf: 4426933 bytes, checksum: 5733e09060e6e08135de26c11374b171 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-05-28T17:29:36Z (GMT) No. of bitstreams: 1 Vers?o completa da disserta??o-stefaniemuraro.pdf: 4426933 bytes, checksum: 5733e09060e6e08135de26c11374b171 (MD5) / Made available in DSpace on 2018-05-28T17:34:08Z (GMT). No. of bitstreams: 1 Vers?o completa da disserta??o-stefaniemuraro.pdf: 4426933 bytes, checksum: 5733e09060e6e08135de26c11374b171 (MD5) Previous issue date: 2018-03-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Respiratory syncytial virus (RSV) is a major cause of diseases of the respiratory tract in humans being mainly associated with bronchiolitis, chronic obstructive pulmonary disease (COPD) and asthma exacerbation. RSV infection occurs primarily in pulmonary epithelial cells and, once infection is established, an innate immune response is triggered and mainly neutrophil recruitment is induced. Neutrophils can extrude neutrophil extracellular traps (NETs) capable of entrapping and inactivate a multitude of microorganisms because of its composition and due to the stringy nature of DNA fibers. Recently, was demonstrated that RSV particles and its fusion (F) protein were able to induce the release NETs coated with neutrophil elastase and myeloperoxidase, both antimicrobial peptides. Also, was observed that the excessive formation of NETs can have negative consequences to the host, such as airway obstruction during RSV infection. Therefore, the aim was to evaluate the mechanisms involved in NET formation induced by RSV infection of neutrophils, alveolar epithelial cells (A549) or lung fibroblasts (MRC5). Human neutrophils were infected with RSV and were able to induce NETs release only after 3 hours of stimulation indicating classical NETosis. Next was characterized NETs formation during infection associating DNA extrusion with MPO, NE and F protein of RSV. Was also observed NADPH oxidase and PAD4 dependence and PI3K/AKT, ERK and p38 MAPK pathways during infection. The inhibition of these signaling pathways, PAD4 and ROS production abolished NET formation. Considering a possible involvement of necroptosis during NETs production, were tested MLKL and RIPK inhibitors and evaluated LDH release in the supernatant of infected neutrophils. Neutrophils released LDH and depend on necroptosis induction to produce NETs. Likewise, neutrophils were co-cultured with A549 or MRC5 cells infected with RSV. Both A549 and MRC5 cells triggered NET release by human neutrophils in a virus concentration-dependent manner, the opposite occurs when used UV-inactivated virus. Briefly, RSV induces the classical/ROS-dependent NETosis by human neutrophils, and this effect relies on specific kinases activity. Furthermore, neutrophils are able to recognize pulmonary cells infected by RSV, releasing NETs. Thus, NETs release control could be crucial for minimizing tissue inflammation caused by RSV infection. / O v?rus sincicial respirat?rio (VSR) ? uma das principais causas de doen?as do trato respirat?rio em humanos sendo associado principalmente com bronquiolite, doen?a pulmonar obstrutiva cr?nica (DPOC) e exacerba??o de asma. O VSR infecta principalmente c?lulas epiteliais pulmonares e, uma vez que a infec??o ? estabelecida, uma resposta imune inata ? desencadeada e ocorre o recrutamento de c?lulas do sistema imune, principalmente neutr?filos. Os neutr?filos podem liberar redes extracelulares de neutr?filos (NETs) capazes de capturar e inativar uma grande quantidade de microrganismos devido ? sua composi??o e natureza fibrosa das fibras de DNA. Recentemente, foi demonstrado que part?culas do VSR al?m da prote?na de fus?o (F) do v?rus foram capazes de induzir a libera??o de NETs revestidas com elastase neutrof?lica e mieloperoxidase, ambos pept?deos com atividade antimicrobiana. Al?m disso, observou-se que a forma??o excessiva de NETs pode ter consequ?ncias negativas para o hospedeiro, como a obstru??o das vias a?reas durante a infec??o por VSR. Portanto, o objetivo foi avaliar os mecanismos envolvidos na forma??o de NET induzida pela infec??o por RSV em neutr?filos humanos, c?lulas epiteliais alveolares (A549) ou fibroblastos pulmonares (MRC5). Neutr?filos humanos foram infectados com VSR e foram capazes de induzir a libera??o de NETs somente ap?s 3 horas de infec??o, indicando uma NETose cl?ssica. Em seguida, foi caracterizada a forma??o de NETs durante a infec??o associando a extrus?o de DNA com as prote?nas MPO, NE e com a prote?na F do VSR. Tamb?m se observou a depend?ncia de NADPH oxidase e PAD4 e das vias de sinaliza??o PI3K / AKT, ERK e p38 MAPK durante a infec??o. A inibi??o dessas vias de sinaliza??o, da produ??o de PAD4 e de EROs aboliu a forma??o de NET. Considerando um poss?vel envolvimento da necroptose na produ??o de NETs, foram utilizados inibidores de MLKL e RIPK1 e foi avaliada a libera??o de LDH no sobrenadante de neutr?filos infectados. Os neutr?filos liberaram LDH e dependeram da ativa??o da necroptose para produzir NETs. Do mesmo modo, os neutr?filos foram co-cultivados com c?lulas A549 ou MRC5 infectadas com VSR. Ambas as c?lulas A549 e MRC5 desencadearam a libera??o de NET por neutr?filos humanos de uma maneira dependente da concentra??o de v?rus, o oposto ocorreu quando usado um v?rus UV-inativado. Resumidamente, o VSR induz a NETose cl?ssica / dependente de EROs em neutr?filos humanos, e este efeito depende de atividade espec?fica de quinases. Al?m disso, os neutr?filos s?o capazes de reconhecer c?lulas pulmonares infectadas pelo VSR, induzindo a libera??o NETs. Assim, o controle de libera??o de NETs pode ser crucial para minimizar a inflama??o do tecido causada pela infec??o por VSR.
87

Experi?ncias de fam?lias de crian?as com microcefalia por Zika v?rus

Vale, Paulo Roberto Lima Falc?o do 22 February 2018 (has links)
Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-07-20T21:53:39Z No. of bitstreams: 1 DISSERTA??O PAULO ROBERTO finalz?o 09 03.pdf: 3626215 bytes, checksum: a916a4a7fbf307b65ccad4330d1dd18c (MD5) / Made available in DSpace on 2018-07-20T21:53:39Z (GMT). No. of bitstreams: 1 DISSERTA??O PAULO ROBERTO finalz?o 09 03.pdf: 3626215 bytes, checksum: a916a4a7fbf307b65ccad4330d1dd18c (MD5) Previous issue date: 2018-02-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Study qualitative, exploratory, with the objective of understanding the experiences of families of children with microcephaly by Zika virus. For the production of empirical data we explore the narratives of relatives contained in videos posted on the YouTube Internet platform published between 10/01/2015 and 07/31/2016, as well as narratives obtained from an in-depth interview, of the story-theme design applied in 11 family members of children with microcephaly attended at the Association of Parents and Friends of the Exceptional in Feira de Santana, as well as field diary material. The data collection took place between September and November 2017. For the treatment of the data we adopted the thematic content analysis and the iconographic analysis. The results are organized in: Article 1 - Bad news: experiences and feelings of families regarding the diagnosis of microcephaly by Zika virus; A session entitled: Understanding the family dynamics of study participants; Article 2 - "Well run, very fast ...": experiences of care of mothers of children with microcephaly by Zika; Article 3 - Family organization to take care of the child with microcephaly by z?ka virus. Microcephaly is revealed in the prenatal period, through imaging tests, or during the immediate or late postpartum. Relatives live with feelings of sadness, despair, pain, fright, commotion, disorientation and terror. After diagnosis, family members seek to understand microcephaly through internet resources, and question God's permission and the relevance of scientific knowledge. Mothers experience day-to-day organizing and cleaning the home environment, caring for their children and the specific care of the child with microcephaly, regarding lullaby, since children cry frequently, requiring the mother to spend hours with the child in the lap; Give a shower; change diapers; to feed; play; and, stimulate. They learn to differentiate cognitive, psychomotor, auditory, and visual impairments; recognize progress in the development and new needs of children; identify episodes of seizure; consider patience and attention relevant to care; and, seek to learn about new thematic and unknown terms such as calcifications. Family members build a network of solidarity and unity for the benefit of the child, family relationships are strengthened, bringing together previously conflicting relationships. Caregivers include mothers, fathers, grandparents, sisters, cousins, aunts, friends and neighbors, with the mother being the protagonist who also coordinates and defines the roles played by other people. Family members practice care that has been organized in four dimensions: "Take care"; Encourage; Access Resources and Services. We recommend that family members and health workers attend to the restriction of social interaction, weakening marital relationships, jealousy behaviors on the part of siblings, worsening of grandparents' health conditions, and financial difficulties that may affect the family of children with microcephaly. / Estudo qualitativo, do tipo explorat?rio, com objetivo de compreender as experi?ncias de fam?lias de crian?as com microcefalia por Zika v?rus. Para produ??o de dados emp?ricos exploramos as narrativas de familiares contidas em v?deos postados na plataforma virtual da internet YouTube publicados entre 01/10/2015 e 31/07/2016, e tamb?m narrativas obtidas de entrevista em profundidade, do desenho est?ria-tema aplicados em 11 familiares de crian?as com microcefalia atendidos na Associa??o de Pais e Amigos dos Excepcionais em Feira de Santana, al?m de material do di?rio de campo. A coleta de dados ocorreu entre setembro a novembro de 2017. Para tratamento dos dados adotamos a an?lise de conte?do tem?tica e a an?lise iconogr?fica. Os resultados encontram-se organizados em: Artigo 1 ? M?s not?cias: experi?ncias e sentimentos de fam?lias face o diagn?stico de microcefalia por Zika v?rus; Uma se??o intitulada: Compreendendo a din?mica familiar dos participantes do estudo; Artigo 2 ? ?Bem corrido, muito corrido...?: experi?ncias de cuidado de m?es de crian?as com microcefalia por Zika; Artigo 3 ? Organiza??o familiar para cuidar da crian?a com microcefalia por z?ka v?rus. A microcefalia ? revelada no per?odo pr?-natal, atrav?s de exames de imagens, ou durante o p?s-parto imediato ou tardio. Os familiares convivem com sentimentos de tristeza, desespero, dor, susto, como??o, desorienta??o e terror. Ap?s o diagn?stico, os familiares buscam compreender a microcefalia atrav?s dos recursos da internet, e questionam a permiss?o de Deus e a relev?ncia do conhecimento cient?fico. As m?es experienciam o dia a dia organizando e limpando o ambiente dom?stico, exercendo os cuidados aos filhos e o cuidado espec?fico ? crian?a com microcefalia, referentes a: ninar, pois as crian?as choram com frequ?ncia, necessitando que a m?e passe horas com a crian?a no colo; dar banho; trocar fralda; alimentar; brincar; e, estimular. Elas aprendem a diferenciar as defici?ncias cognitivas, psicomotoras, auditivas e visuais; reconhecem os avan?os no desenvolvimento e as novas necessidades das crian?as; identificam epis?dios de convuls?o; consideram a paci?ncia e a aten??o relevantes para o cuidado; e, buscam apreender sobre novas tem?ticas e termos desconhecidos como calcifica??es. Os familiares constroem uma rede de solidariedade e uni?o em prol da crian?a, as rela??es familiares s?o fortalecidas, aproximando rela??es antes conflituosas. Participam do cuidado as m?es, pais, av?s, irm?s (os), primos (as), tias (os), amigas e vizinhas, havendo protagonismo da m?e que tamb?m coordena e define os papeis desempenhados pelas outras pessoas. Os familiares exercem cuidados que foram organizados em quatro dimens?es: Cuidar Integralmente; ?Tomar Conta?; Estimular; Acessar Recursos e Servi?os. Recomendamos que os familiares e trabalhadores da sa?de atentem para a restri??o do conv?vio social, enfraquecimento das rela??es conjugais, comportamentos que indiquem ci?mes por parte dos irm?os, agravamento das condi??es de sa?de das av?s e dificuldades financeiras que podem repercutir na fam?lia de crian?as com microcefalia.
88

Participa??o do v?rus sincicial respirat?rio, das esp?cies reativas de oxig?nio e da autofagia na forma??o de redes extracelulares de eosin?filos na asma

Silveira, Josiane Silva 26 October 2018 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-11-01T18:12:18Z No. of bitstreams: 1 disserta??o Josiane Silva Silveira vers?o final corrigida.pdf: 4036302 bytes, checksum: cdea806bf90b79da9a4047282152d203 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-11-05T12:55:20Z (GMT) No. of bitstreams: 1 disserta??o Josiane Silva Silveira vers?o final corrigida.pdf: 4036302 bytes, checksum: cdea806bf90b79da9a4047282152d203 (MD5) / Made available in DSpace on 2018-11-05T13:36:59Z (GMT). No. of bitstreams: 1 disserta??o Josiane Silva Silveira vers?o final corrigida.pdf: 4036302 bytes, checksum: cdea806bf90b79da9a4047282152d203 (MD5) Previous issue date: 2018-10-26 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / INTRODUCTION: asthma is a chronic inflammatory disease characterized by secretion of elevated levels of cytokines (interleukin (IL)-4, IL-5 and IL-13), reactive oxygen species (ROS), autophagy and eosinophil extracellular traps (EETs) release in airway. Moreover, respiratory syncytial virus (RSV) infection may facilitate allergic sensitization development as well as exacerbate asthma symptoms. Recently, studies have demonstrated an increase of autophagy in eosinophils of asthmatic patients, contributing to an increase in inflammatory response. In asthma, an increase in EETs release may cause tissue damage and an increase in mucus viscosity, which contribute to airway obstruction and reduction of lung function. However, the mechanism of EETs formation and its pathophysiologic role in asthma are poorly understood. OBJECTIVE: the aim of this dissertation was to elucidate some mechanisms involved in EETs release in asthma. We investigated whether the respiratory syncytial virus (RSV) could induce EETs in vitro in bronchoalveolar lavage fluid (BALF) eosinophils of an experimental asthma model. Moreover, we evaluated ROS and autophagy participation in mechanisms involved in EETs formation. METHODS: in order to perform the experimental model of asthma, BALB/cJ mice were sensitized with two subcutaneous injections of ovalbumin (OVA) on days 0 and 7, followed by three intranasal challenges with OVA on days 14, 15 and 16 of the protocol. In paper 1, BALF eosinophils of OVA group and control group were stimulated with RSV (103 PFU/mL) in vitro for 3 hours. After that, culture supernatant was collected in order to perform the analyses proposed in this study which were evaluated according to the specific objectives of this paper. In paper 2, during the experimental asthma protocol, mice were treated intranasally with a nicotinamide adenine dinucleotide phosphate oxidase (NDPH oxidase) inhibitor, diphenyleneiodonium (DPI), or a glutathione precursor, N-acetylcysteine (NAC). In paper 3, mice were treated intranasally with an autophagy inhibitor, 3-Methyladenine (3-MA). Treatments were performed 45 minutes before of the three intranasal administrations with OVA. At the end of the protocol, BALF and lung tissue were collected to perform the techniques discribed in each of the papers, according to their specific objectives. RESULTS: in paper 1, we verified an increase in EETs release in BALF eosinophils from OVA group stimulated with RSV in vitro. RSV in vitro decreased IFN-? in BALF cells when compared to the OVA group. In paper 2, we showed that in NAC-treated OVA group there was a decrease in the inflammatory cells in BALF and lung tissue. DPI or NAC treatments reduced EPO activity, goblet cells hyperplasia, inflammatory cytokines and NF?B p65 immunocontent in lung, and they helped in decreasing ROS production in lung. Furthermore, NAC increased catalase (CAT) activity in lung. However, only NAC treatment improved mitochondrial energy metabolism in lung. We showed that DPI or NAC reduced EETs formation in BALF from the OVA group. In paper 3, we showed that in 3-MA-treated OVA group there was a decrease in the inflammatory cells, EPO activity, goblet cells hyperplasia, inflammatory cytokines, NF?B p65 immunocontent, and oxidative stress in airway. Moreover, 3-MA was able to improve mitochondrial energy metabolism and increase Na+,K+-ATPase activity. We also demonstrated that 3-MA decreased light chain 3B (LC3B) in BALF cells and lung tissue as well as reduced EETs formation in BALF. CONCLUSION: our results verified an important role for RSV in the induction of EETs release. Moreover, DPI, NAC and 3-MA treatments decreased airway inflammation, oxidative stress and EETs release in asthma. Our data suggested that RSV, ROS and autophagy participate in the mechanisms for EETs release in asthma. Thus, identification of mechanisms that regulate EETs formation in asthma may contribute to a better understanding of the pathogenesis of this chronic inflammatory disease which damages patients? quality of life and is responsible for a high economic cost for the Brazilian Single Health System (SUS). / INTRODU??O: a asma ? uma doen?a inflamat?ria cr?nica caracterizada pela secre??o de elevados n?veis de citocinas do perfil T helper 2 (Th2) como interleucina (IL)-4, IL-5 e IL-13, esp?cies reativas de oxig?nio (EROs), aumento da autofagia e forma??o redes extracelulares de eosin?filos (EETs). A infec??o pelo v?rus sincicial respirat?rio (VSR) pode facilitar o desenvolvimento da sensibiliza??o al?rgica bem como exacerbar os sintomas da doen?a. Recentemente, estudos t?m demonstrado o aumento da autofagia em eosin?filos das vias de pacientes asm?ticos, contribuindo para o aumento da resposta inflamat?ria nas vias a?reas. Na asma, a produ??o excessiva de EETs pode causar dano tecidual e aumento da viscosidade do muco, podendo contribuir para o aumento da obstru??o da via a?rea e redu??o da fun??o pulmonar. Entretanto, os mecanismos de forma??o das EETs e seu papel fisiopatol?gico na asma s?o pouco compreendidos. OBJETIVO: esta disserta??o teve como objetivo elucidar alguns mecanismos envolvidos na libera??o de EETs na asma. Avaliamos a participa??o do VSR in vitro, das EROs e da autofagia nos mecanismos envolvidos na libera??o das EETs em eosin?filos do lavado broncoalveolar (LBA) em um modelo experimental de asma. METODOLOGIA: para o desenvolvimento do modelo experimental de asma, camundongos BALB/cJ foram sensibilizados com duas inje??es subcut?neas de ovalbumina (OVA) nos dias 0 e 7 seguidos por tr?s desafios intranasais com OVA nos dias 14, 15 e 16 do protocolo. No artigo cient?fico 1, eosin?filos do LBA de animais do grupo OVA e do grupo controle foram estimulados com VSR (103 PFU/mL) in vitro por 3 horas. Ap?s este per?odo, o sobrenadante da cultura foi coletado para a realiza??o das t?cnicas avaliadas conforme os objetivos espec?ficos deste artigo cient?fico. No artigo cientifico 2, durante o protocolo experimental de asma, os animais foram tratados via intranasal com um inibidor da nicotinamida adenina dinucleot?deo fosfato oxidase (NADPH oxidase), difenileno-iod?nio (DPI), ou com um precursor da glutationa, N-acetilciste?na (NAC), 45 minutos antes dos tr?s desafios intranasais com OVA. J? no artigo cientifico 3, os animais foram tratados via intranasal com um inibidor de autofagia, 3-metiladenina (3-MA), 45 minutos antes dos tr?s desafios intranasais com OVA. Ao final do protocolo o LBA e o tecido pulmonar foram coletados para a realiza??o das t?cnicas avaliadas em cada um dos artigos cient?ficos, conforme seus objetivos espec?ficos. RESULTADOS: no artigo cientifico 1, observamos um aumento na libera??o de EETs em eosin?filos do LBA de animais submetidos ao modelo experimental de asma e estimulados com VSR in vitro. Por outro lado, o VSR in vitro foi capaz de diminuir os n?veis de IFN-? no sobrenadante da cultura de eosin?filos do LBA. Em rela??o aos resultados do artigo cient?fico 2, verificamos que no grupo OVA tratado com NAC ocorreu uma diminui??o no n?mero de c?lulas inflamat?rias no LBA bem como uma redu??o no infiltrado inflamat?rio pulmonar. Al?m disso, os animais do grupo OVAM tratados com DPI ou NAC apresentaram uma redu??o da enzima EPO, hiperplasia de c?lulas caliciformes, citocinas inflamat?rias e da prote?na fator nuclear kappa B (NF?B p65). Os tratamentos com DPI ou NAC foram capazes de reduzir a forma??o de EROs, aumentar a atividade da enzima catalase antixidante (CAT). Por outro lado, par?metros do metabolismo energ?tico mitocondrial aumentaram somente com o tratamento com NAC. Por fim, demonstramos que os tratamentos com DPI ou NAC foram capazes de reduzir a forma??o de EETs do LBA. No artigo cient?fico 3, observamos que no grupo OVA tratado com o inibidor de autofagia, 3-MA, ocorreu uma diminui??o no n?mero de c?lulas inflamat?rias no LBA bem como uma redu??o do infiltrado inflamat?rio pulmonar. Al?m disso, os animais tratados com 3-MA apresentaram uma redu??o nos n?veis da enzima EPO, hiperplasia de c?lulas caliciformes, citocinas inflamat?rias e da prote?na NF?B p65. O tratamento com 3-MA foi capaz de reduzir a forma??o de EROs bem como aumentar os n?veis da enzima antioxidante CAT. O tratamento com 3-MA tamb?m melhorou par?metros do metabolismo energ?tico mitocondrial e a atividade da enzima Na+,K+ATPase. Demonstramos tamb?m que o tratamento com 3-MA diminuiu o imunoconte?do da prote?na light chain 3B (LC3B) em eosin?filos do LBA e no tecido pulmonar e reduziu a forma??o de EETs no LBA. CONCLUS?O: Nossos resultados demonstram um importante papel do VSR na indu??o da libera??o de EETs. Al?m disso, verificamos que os tratamentos com DPI, NAC e 3-MA foram capazes de reduzir a inflama??o das vias a?reas, o estresse oxidativo e a libera??o de EETs no LBA. Demonstramos que o VSR, as EROs e a autofagia participam dos mecanismos que regulam o processo de libera??o das EETs na asma. Assim, a identifica??o de alguns desses mecanismos envolvidos na libera??o de EETs na asma pode contribuir para uma melhor compreens?o da patog?nese desta doen?a inflamat?ria cr?nica que prejudica a qualidade de vida dos pacientes e ? respons?vel por um alto custo econ?mico para o Sistema ?nico de Sa?de (SUS).
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MECHANICAL PROPERTIES OF Sc₀․₁Ce₀․₀₁Zr₀․₈₉O₂ ELECTROLYTE MATERIAL FOR INTERMEDIATE TEMPERATURE SOLID OXIDE FUEL CELLS

Lim, Wendy 2009 December 1900 (has links)
Scandia doped zirconia has been considered a candidate for electrolyte material in intermediate temperature Solid Oxide Fuel Cells (SOFCs) due to its high ionic conductivity, chemical stability and good electrochemical performance. The aim of this study is to determine the mechanical properties of SCZ, ie. zirconia (ZrO₂) doped with Scandia (Sc₂O₃) and small amount of ceria (CeO₂) that are important for reliability and durability of the components manufactured from SCZ. The SCZ was prepared from powder by uniaxiall cold pressing at subsequent sintering at 1550 ºC for 4 hours. The density and porosity of the sintered samples was measured following the ASTM Standard C20-00 for alcohol immersion method. A pure cubic phase of SCZ sample was identified by X-ray diffraction (XRD) at room temperature. Quantitative compositional analyses for Zr, Sc, Ce, Hf and Ti were carried out on a Cameca SX50 electron microprobe with wavelength-dispersive spectroscopy (WDS) and energy-dispersive spectroscopy (EDS). Scanning Electron Microscopy (SEM) images were acquired using both secondary electron (SE) and back-scattered electron (BSE) detectors. WDS and EDS analysis also revealed that Zr, Sc, Ce, Hf and Ti are relatively homogeneously distributed in the structure. The average grain size of sintered SCZ samples was measured to be 4 μm. Thermal expansion at different temperatures for the SCZ ceramic was determined using Thermal Mechanical Analyzer, and the instantaneous Coefficient of Thermal Expansion (CTE) was found to be 8.726х10⁻⁶ 1/°C in the in 25-400 °C temperature range. CTE increases monotonically with temperature above 400 ºC to 1.16х10⁻⁵ at 890 °C, most likely as a result of thermo-chemical expansion due to an increase in oxygen vacancy concentration. Room temperature Vickers hardens of 12.5 GPa was measured at loads of 1000 g, while indentation fracture toughness was found to vary from 2.25 to 4.29 MPa m¹⁄², depending on the methodology that was used to calculate fracture toughness from the length of the median corner cracks. Elastic moduli, namely Young and shear moduli were determined using Resonance Ultrasound Spectroscopy (RUS). It was found that elastic moduli decreases with temperature in non-linear manner, with significant drop in the 300-600 °C temperature range, the same temperature range in which loss modulus determined by Dynamic Mechanical Analyzer exhibits frequency dependant peaks. The high loss modulus and significant drop in elastic moduli in that temperature regime is attributed to the relaxation of doping cation-oxygen vacancies clusters. The flexural strength in 4-point bending was measured at room temperature, 400 °C, 600 °C and 800 °C. and the results were analyzed using Weibull statistics. It was found that flexural strength changes with temperature in a sigmoidal way, with the minimum strength at around 600 °C. Non-linear decrease in strength with temperature can be traced back to the changes in elastic moduli that are caused predominately by relaxation of oxygen vacancies.
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Kan strålar av ljus tyda det förflutna? : Användning av Reflectance Transformation Imaging (RTI) för att tyda runinskrifter på Pireus-lejonet

Nazerian, Simon January 2014 (has links)
This paper deals with testing the method Reflectance Transformation Imaging (RTI) on the copy of the Piraeus-lion in Historic Museum in Stockholm. The purpose is to find out if it is possible to gather more information about the runic inscriptions. RTI is a method that records the surface normal of individual pixels in a digital photograph by analyzing the impact of light coming from different angles of entrance. RTI produces sort of a 3D-image of the object. There will be an overview of earlier interpretations of the runic scripts written on the lion as well as an overview of Varangians in the southeast. After examination of the lion with RTI, has a conclusion been made that the method should be performed again on similar items, and on the copy of the Piraeus-lion to evaluate its full potential.

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