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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.
171

Caractérisation génomique et génétique des gliomes diffus de bas grade de l’adulte / Genomic and genetic characterisation of adult low-grade gliomas

Alentorn, Agusti 10 March 2014 (has links)
La caractérisation moléculaire multidimensionnelle des tumeurs et des tumeurs gliales en particulier est une étape importante pour l’identification de biomarqueurs (diagnostique, pronostique, théranostique et/ou de prédisposition), pour l’identification de cibles thérapeutiques et pour une meilleure compréhension de l’oncogénèse moléculaire.Nos travaux ont permis de confirmer et de consolider certaines données de la littérature comme par exemple : (i) la valeur pronostique favorable de la codélétion 1p/19q, (ii) la valeur pronostique favorable de la mutation IDH, (iii) le caractère mutuellement exclusive des mutations TP53 et de la codélétion 1p/19q et (iv) la rareté des altérations génétiques du PDGFRA dans les gliomes de bas grade (GDBG). De manière plus originale, nous avons identifié plusieurs sous-groupes génomiques de GDBG pertinents sur le plan clinico-biologique, notamment au sein des GDBG non 1p/19q codélétés : (i) 19q-délété ; (ii) 11p-délété, (iii) 7-gagné, (iv) 19-gagné et (v) inclassés. La perte du bras chromosomique 19q annule la valeur pronostique favorable de la mutation IDH dans les GDBG non 1p/19q codélétés. Nous avons également identifié des mutations géniques originales dans les GDBG (i.e. mutation TEP1 et RNF40) qui renforcent le rôle des télomères et du remodelage de la chromatine au sein des GDBG.Enfin, nous nous sommes concentrés sur la caractérisation des GDBG 11p-délétés qui sont de phénotype majoritairement astrocytaire et de moins bon pronostic. Ces GDBG surexpriment des gènes des cellules immunitaires (les GIM -Glioma infiltrating microglia-, les macrophages de type 1, les macrophages de type 2) et sont infiltrés par des cellules macrophagiques et microgliales. Ce microenvironnement dérégulé peut constituer une cible thérapeutique au sein des GDBG 11p-délétés. En conclusion, nos travaux participent à la dissection clinico-moléculaire des GDBG et à préciser la biologie d’un sous-type de GDBG caractérisé la perte du bras chromosomique 11p. / Multildimensional molecular characterization of tumors and more specifically of gliomas is of pivotal importance to identify: (i) new biomarkers (i.e. diagnostic, prognostic, theranostic or predisposing), (ii) new therapeutic targets and (iii) to improve our understanding of molecular oncogenesis.Our work has confirmed and consolidated previous data published in the literature, for example that: (i) 1p/19q co-deletion is associated with better prognosis, (ii) IDH mutation is associated with better prognosis, (iii) TP53 mutations and 1p/19q codeletion are mutually exclusive and (iv) PDGFRA is rarely altered, at genomic level, in low-grade gliomas (LGG).More originally, we have identified several genomic groups, with clinical and biological relevances, in LGG and more specifically in LGG without 1p/19q co-deletion: (i) 19q-deleted, (ii) 11p-deleted, (iii) 7-gained, (iv) 19-gained and (v) unclassified. Interestingly, 19q deletion abrogates the positive prognostic value of IDH mutation in LGG without 1p/19q codeletion.We have also identified new recurrent somatic gene mutations in LGG (i.e. TEP1 and RNF40 mutations), supporting the critical role of telomeres and chromatin remodelling in LGG.Finally, we have characterized further 11p-deleted LGG that exhibit mostly astrocytic phenotype and poor prognosis. This subgroup includes LGG overexpressing genes of inflammatory/immune cells (GIM -Glioma infiltrating microglia-, M1 macrophages and M2 macrophages) and infiltrated by macrophagic/microglial cells. This peculiar microenvironment detected in 11p-deleted LGG might be used as a therapeutic target. In conclusion, our work participates to characterize clinico-biological portrait of LGG and to describe a singular genomic subgroup of LGG characterized by 11p loss.
172

The role of cardiokines in metabolic heart disease

Tu, Vivian Huikang 08 April 2016 (has links)
Metabolic heart disease (MHD) caused by obesity or diabetes is characterized by cardiac hypertrophy, diastolic dysfunction, and fibrosis - a maladaptive remodeling of the extracellular matrix. Though the influence of cardiac fibrosis on the left ventricular diastolic dysfunction has been reported, little is known about the cardiac-specific secreted autocrine, paracrine, or endocrine factors termed "cardiokines" in MHD. Transforming growth factor beta (TGF-b1) is a well-known inducer of cardiac fibrosis. However, the role TGF-b2 in mediating cardiac fibrosis has yet to be described. In addition, follistatin-like 3 (FSTL3), an extracellular inhibitor of activin A and myostatin, is found to be elevated in end-stage heart failure patients and obese individuals. FSTL3 has been suggested as a cardiokine, yet its role in MHD has not been established. To identify cardiokines induced by MHD, two relevant mouse models were employed in this study: the high-fat high sucrose (HFHS) diet feeding model and the cardiomyocyte-specific Fatp1 overexpressing transgenic mouse model. Interstitial fibrosis was observed in both models, accompanied by fibrotic gene expression and anti-fibrotic miR-29 suppression. It was found that Tgf-b1 and Tgf-b2 mRNA were upregulated by 85% and 76%, respectively, in the non-myocytes of 1-month HFHS-fed mice, while Fstl3 was increased by 30% in the myocytes. In contrast, in the FATP1 transgenic animals, Tgf-b2 and Fstl3 were elevated by 3.8-fold and 1.9-fold in the myocytes while Tgf-b1 remained unchanged compared to control animals. The in vitro results tested in NIH3T3 and primary fibroblast cultures indicate that both TGF-b1 and TGF-b2 exerted profibrotic effects via activation of SMAD proteins and collagen synthesis, but FSTL3 did not. Plasma samples collected from patients with metabolic syndrome showed increased FSTL3 levels with strong correlations with cardiac hypertrophy and impaired diastolic function. Overall, this study has demonstrated that TGF-b1 and TGF-b2 are the key profibrotic cardiokines induced in MHD. The study has also revealed the role of FSTL3 as a biomarker for LV hypertrophy induced in MHD. The results presented here should facilitate the development of better diagnosis and treatment for this disease in the future.
173

Correlação entre ingestão de aflatoxina B1, concentração sérica e urinária de AFB1-adutos e expressão hepática de marcadores moleculares relacionados à hepatocarcinogênese em ratos / Correlation between aflatoxin B1 intake and serum and urinary concentrations of AFB1-adducts and hepatic expression of molecular markers related to hepatocarcinogenesis in rats

Trotta, Mauricio de Rosa 22 August 2016 (has links)
A aflatoxina B1 (AFB1) é um metabólito de fungos do gênero Aspergillus que crescem naturalmente em alimentos. Devido às condições climáticas e às práticas agrícolas inadequadas, países em desenvolvimento, incluindo o Brasil, possuem alta possibilidade de exposição à AFB1 através de alimentos contaminados. A exposição crônica a essa micotoxina pode acarretar no surgimento de carcinoma hepatocelular e explicar a incidência desse tumor na ausência de fatores como hepatites virais e cirrose. Após a ingestão oral, a AFB1 é biotransformada para a sua forma genotóxica que se liga ao DNA das células hepáticas. Isso gera mutações que podem ser consideradas promotoras da hepatocarcinogênese. Na sequência desse processo, ocorre a formação de novos adutos de aflatoxina que podem se ligar à proteína plasmática ou serem excretados pela urina, respectivamente, AFB1-lisina e AFB1-N7-guanina. Esses compostos podem ser detectados e funcionar como biomarcadores da exposição e da toxicidade da AFB1. A AFB1 foi administrada enteralmente em ratos Wistar, via gavagem, durante 90 dias, sendo essa forma de exposição a mais próxima daquela pela qual os seres humanos estão suceptíveis. Os animais foram divididos em quatro grupos experimentais: Grupo Controle (sem AFB1), AFB50 (50 ppb), AFB100 (100 ppb) e AFB200 (200 ppb), sendo a concentração de AFB1 em parte por bilhão (ppb) por kilograma de dieta consumida. Foram realizadas avaliações de bioquímica plasmática de aspartato aminotransferase (AST) e alanina aminotransferase (ALT); alterações na expressão hepática de genes e proteínas relacionadas ao processo de hepatocarcinogênese (Ciclina D1, p53, ?-catenina, Proibitina, p27Kip1 e Glutationa-S-Transferase-p1-GSTP) por meios das técnicas de imuno-histoquímica e PCR em tempo real. Foram realizadas determinações dos níveis dos adutos da AFB1 no soro, na urina. Os resultados mostraram que houve aumento na expressão de AST e ALT em todos os grupos que receberam AFB1. No grupo AFB200 e, em menor proporção no AFB100, surgiram diversos focos de hepatócitos alterados marcados positivamente com GSTP, que são lesões pré-neoplásicas bem determinadas e consideradas endpoints em ensaios de hepatocarcinogênese experimental. A análise das proteínas hepáticas indicou que as lesões decorrentes da AFB1 nos grupos AFB200 e AFB100 apresentaram superexpressão de ciclina D1, p53, ?-catenina, proibitina, indicando a participação delas em vias que favorecem a hepatocarcinogênese. Adicionalmente, ocorreu uma redução na expressão gênica do gene p27, o que também indica uma condição favorável para a progressão neoplásica para a formação de carcinoma hepatocelular. A quantificação dos níveis de adutos no soro e na urina apontou que a formação desses compostos foi dose-dependente com as diferentes concentrações de AFB1 empregadas. Além disso, houve correlação entre a formação dos adutos com a expressão das proteínas Ciclina D, p53, ?-catenina e Rb. Sendo assim, foi possível, experimentalmente, apontar as principais proteínas envolvidas na hepatocarcinogênese e indicar que os adutos de aflatoxina no soro e na urina podem ser biomarcadores úteis para mensurar a exposição e o dano causado pela ingestão subcrônica de AFB1. / Aflatoxin B1 (AFB1) is metabolite produced by fungi of genus Aspergillus that grows naturally in food. Due to weather conditions and inadequate agricultural practices, developing countries, including Brazil, have high possibility of exposure to AFB1- contamined food. Chronic exposure to this mycotoxin may result in the emergence of hepatocellular carcinoma and explain the incidence of this tumor in the absence of factors such viral hepatitis and cirrhosis. After oral ingestion, AFB1 is biotransformed to its genotoxic form that binds to DNA in liver cells. This leads mutations that may be considered promoters of hepatocarcinogenesis. Following this process, there is the formation of new adducts of aflatoxins that can bind to plasma proteins or are excreted in the urine, respectively, AFB1-lysine and AFB1-N7-guanine. These compounds can be detected and work as biomarkers of exposure and toxicity of AFB1. AFB1 was administered in Wistar rats enterally, via gavage, for 90 days, and this form of exposure is closest which humans are susceptible. The animals were separated into four groups: control group (without AFB1), AFB50 (50 ppb), AFB100 (100 ppb) and AFB200 (200 ppb), in which concentration of AFB1 in part per billion (ppb) per kilogram of diet consumed by animals. It were performed liver biochemistry plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) assessments; changes in hepatic expression of genes and proteins related to hepatocarcinogenesis (Cyclin D1, p53, ?-catenin, Prohibitin, p27Kip1 e Glutatione-STransferase-p1-GST-P) by immunohistochemical and real-time PCR techniques. The levels of AFB1 adducts of serum and urine were performed. The results showed increase in AST and ALT levels in all groups receiving AFB1. In group AFB200 and, lesser extent in AFB100, emerged several altered hepatocyte foci positively marked with GST-P, which are well determined preneoplastic lesions and deemed endpoints in experimental hepatocarcinogenesis assays. Analysis of liver proteins indicated that damage from AFB1 in groups AFB200 and AFB100 showed overexpression of cyclin D1, p53, ?-catenin, prohibitin, indicating their participation in ways that favor the hepatocarcinogenesis. Additionally, there was a decrease in gene expression of the p27 gene, which also indicates a favorable condition for neoplastic progression to hepatocellular carcinoma. Quantification of adducts levels in serum and urine showed that the formation of these compounds was dose-dependent with different concentrations of AFB1 employed. In addition, there was a correlation between the formation of adducts with the protein expression of Cyclin D, p53, ?-catenin and Rb. Thus, it was possible experimentally to point out the key proteins involved in hepatocarcinogenesis and indicate that aflatoxin adducts in serum and urine can be useful biomarkers to measure exposure and damage caused by subchronic ingestion of AFB1.
174

Desenvolvimento de protocolo de reabilitação no período pós-operatório inicial de artroscopia em equinos / Development of a rehabilitation protocol for inicial postoperative period of arthroscopy in horses

Stievani, Fernanda de Castro 12 September 2014 (has links)
O presente estudo teve por objetivo avaliar protocolo de reabilitação para o período pós-operatório inicial de artroscopias visando diminuir a inflamação no local operado e aumentar a mobilidade articular. Foram utilizados 12 equinos (total de 20 articulações) encaminhados para artroscopia com diagnóstico de osteocondrite dissecante. Dessas, dez articulações receberam protocolo de reabilitação nos primeiros cinco dias do período pós-operatório. O protocolo consistiu em crioterapia, movimentação passiva da articulação e exercício controlado de baixa intensidade, além de uso sistêmico de anti-inflamatório. O outro grupo, também composto por dez articulações, recebeu apenas a terapia utilizada rotineiramente no HOVET-USP, consistido de repouso em baia e antiinflamatório. As articulações foram avaliadas quanto à circunferência em centímetros, ângulo de flexão, termografia, grau de claudicação. Amostras de líquido sinovial foram coletadas imediatamente antes do procedimento cirúrgico (D1), após 48h (D3) e após 96h (D5) para análise física, qualidade do coágulo de mucina, e quantificação de biomarcadores (IL-1, IL-6 e IL-10, PGE2 e SAA). As análises de exame de claudicação, circunferência articular, ângulo de flexão articular e termografia não apresentaram diferenças significativas entre os grupos, nem entre os diferentes dias do mesmo grupo. Na análise do líquido sinovial, a cor e o aspecto apresentaram piora do D1 para o D3, de amarelo claro para avermelhado e de límpido para turvo, respectivamente, nos dois grupos. No entanto, no grupo tratado houve melhora do D3 para o D5, tanto para cor (de avermelhado para maioria xantocrômica e amarela) como aspecto (de maioria turva para ligeiramente turva). No grupo controle os líquidos permaneceram sem alteração em cor e aspecto de D3 para D5, e nas comparações entre os grupos não houve diferença para D1, D3 e D5. A viscosidade do líquido sinovial no grupo controle diminuiu significativamente quando comparados D1, D3 e D5. Já no grupo tratado a diminuição da viscosidade só foi observada quando comparados D1 e D5. O coágulo de mucina apresentou piora de D1 para D3 no grupo controle, com elevação não significativa de D3 para D5, enquanto que para o grupo tratado não houve diferença significativa de D1 para D3 e de D3 para D5, quando comparados o D5 dos dois grupos, o tratado obteve melhor qualidade. As concentrações de interleucina nas amostras não forneceram dados suficientes para análise. Na análise das concentrações de PGE2 não houve diferença entre os grupos nos diferentes momentos, ocorrendo elevação de D3 para D5 em ambos os grupos, porém, no grupo tratado não há diferença entre D1 e D5. Já para SAA os grupos apresentaram comportamento similar de resposta, com elevação de D1 para D3 e queda de D3 para D5, porém menos acentuado no grupo tratado, o que levou a diferença entre os grupos em D3. Pode-se concluir, que o protocolo de reabilitação, apesar de não gerar diferença significativa para as avaliações de exame físico dos animais, proporcionou melhor qualidade de líquido sinovial quanto a cor, aspecto, viscosidade e precipitado de mucina, além de evidenciar menores elevações nas concentrações de marcadores inflamatórios no liquido sinovial durante o período estudado. / The purpose of this study was to evaluate a rehabilitation protocol for the initial postoperative period of metatarsophalangeal, metacarpophalangeal and tarsocrural´s arthroscopies, which seeks to, minimize local inflammation, diminish swelling, promote better joint range of motion and pain relief during such period. Twelve horses participated in this study - amounting to 20 joints - with dissecans ostheochondritis diagnosis. The first group was formed by ten joints, which were treated under rehabilitation protocol for the first 5 days as from the surgery (Treated group). The rehabilitation protocol consisted of cryotherapy, passive range of motion, low intensity exercise and non-steroidal anti-inflammatory drug. The second group also formed of ten joints received the standard HOVET-USP therapy, which consists of rest and non-steroidal anti-inflammatory drug Both groups were treated with the same non-steroidal anti-inflammatory drugs. The joints were measured for circumference, maximal flexion angle, thermography, and lameness score on the day before the surgery (D0) and during the first four days after the surgery. Synovial fluid samples were collected immediately before surgery (D1), within 48 hours (D3), and within 96 hours from the surgery (D5). The analysis evaluated gross appearance (color and aspect), viscosity and mucin clot quality, as well as biomarkers (Il-1, Il-6, Il- 10, PGE2, and SAA) quantification. Lameness examination, joint circumference, flexion angle and thermography evaluation were not significantly different between groups. In synovial fluid analyses de color and aspect have worsen from D1 (clear light yellow) to D3 (turbid hemorrhagic) in both groups. On treated group color and aspect improved from D3 (turbid hemorrhagic) to D5 (xanthochromic and yellow slightly turbid). On treated group there was no difference between D3 and D5. When the groups were compared, none significant differences was seen. The fluid viscosity of control group had significant decrease from D1, to D3 and from D1 and D5. In treated group this viscosity decrease was only seen between D1 and D5. The mucin clot formation worsened when D1 e D3 of control group was compared and remains similar from D3 to D5. In treatment group there were no differences when compared D1 with D3 and D3 with D5. The comparison between groups of D5 has shown treated group improved clot. The interleukin couldn´t be measured on sufficient number of samples for the statistics method. There were no differences between groups on all moments. The PGE2 response was similar in both group with a rise on concentration from D3 to D5. In treated group D1 was similar to D5. This results suggests more evident inflammatory response in the control group. For the SAA the groups have shown similar responses, with an increase from D1 to D3 and decrease from D3 to D5. The response on treated group was less intense and demonstrates lower values in D3 when compared with D3 control group. It was concluded with this study that rehabilitation protocol improved synovial fluid analyses for, color, aspect, viscosity and mucin clot. It even had promoted lower concentrations of inflammatory biomarkers for the treated group during the period.
175

Perfil de expressão tecidual e plasmática dos microRNAs miR-130a, miR-181c e miR-181d em meningiomas grau I, II e III / Profile of plasma and tissue expression of microRNAs miR-130A, miR-181c and miR-181d in meningiomas grade I, II and III

Carneiro, Vinicius Marques 29 May 2015 (has links)
Introdução: Os meningiomas são neoplasias intracranianas de crescimento lento que se originam das células meningoteliais da aracnoide e representam os tumores intracranianos mais comuns, contabilizando 13-26% deste total, sendo um dos primeiros tumores sólidos a terem alterações genéticas identificadas. Inúmeros tem sido os avanços para a melhor compreensão das vias moleculares correlacionadas com a tumorigênese e progressão tumoral dos meningiomas, neste contexto tem se destacado o papel dos microRNAs que são RNAs não-codificantes (ncRNAs) constituídos por 19 a 25 nucleotídeos, cuja função é o silenciamento do RNAm em nível póstranscricional. Portanto, o objetivo do nosso estudo foi avaliar a expressão tecidual e plasmática dos miRNAs miR-181d, miR-181c e miR-130a. Pacientes e métodos: Os miRNAs miR-181d, miR-181c e miR-130a foram selecionados a partir de estudo prévio do nosso grupo pela técnica de análise em larga escala de microarrays, onde foram comparados meningiomas grau I com amostras controles de aracnóides. Neste trabalho foi avaliada expressão destes miRNAs no tecido tumoral e plasma de meningiomas grau I, II e III. Resultados: O miR-181d apresentou-se hiperexpresso nos grupos estudados, no tecido tumoral quanto no plasma. O nível de expressão foi maior de acordo com a progressão do grau do tumor. Os miR-181c e miR-130a não apresentaram diferença estatística nos grupos estudados em ambos tecido tumoral e plasma. Conclusões: O miR-181d tem potencial para ser utilizado como biomarcador para meningiomas e está associado com sua progressão tumoral. / Introduction: Meningiomas are intracranial tumors of slow growth that originate from meningothelial arachnoid cells and represents the most common intracranial tumors, accounting for 13-26% of this total, beeing one of the first solid tumors to have identified genetic alterations There are technological advances available to a better understanding of the molecular pathways correlated with tumorigenesis and tumor progression of meningiomas. The role of microRNAs in this process is very importante. MicroRNAs are non-coding RNAs (ncRNAs) consisting of 19 to 25 nucleotides, with function of mRNA silencing post-transcriptional level. The aim of our study was to evaluate the tissue expression and plasma of miRNAs miR-181d, miR-181c and miR-130a. Patients and methods: The miRNAs miR-181d, miR-181c and miR-130a were selected from a previous study of our group by analysis technique on large scale called microarrays, which were compared meningiomas grade I with arachnoid controls samples. In this study, we evaluated expression of these miRNAs in tumor tissue and plasma meningiomas grade I, II and III. Results: The miR-181d was presented upregulated in the all groups in both tumor tissue and in plasma. The level of expression was increased according to the progression of tumor grade. The miR-181c and miR-130a showed no statistical difference in the groups studied in both tumor tissue and plasma. Conclusions: The miR-181d has potential as a biomarker for meningiomas and is associated with tumor progression.
176

Biomarcadores de exposição em macroalgas Gracilaria domingensis expostas a cádmio e cobre / Biomarkers of exposure in macroalgae Gracilaria domingensis exposed to cadmium and copper

Margarido, Tatiana Cristina Stefani 07 October 2016 (has links)
Nos últimos anos, os metais vêm ganhando maior atenção em estudos devido aos impactos causados no ambiente, sua persistência e capacidade de bioacumulação e biomagnificação. As zonas costeiras por sua localização sofrem danos maiores, principalmente devido à grande quantidade de efluentes depositada nessa área provenientes de atividades urbanas, industriais, agrícolas e mineiras, dentre outras. As algas são organismos que compõe a base da cadeia alimentar e possuem ainda capacidade de estocar metais tornando-os menos disponíveis para as espécies que habitam a região. Tal característica torna esse organismo uma alternativa economicamente viável e ecológica em processos de biorremediação. As macroalgas pertencentes ao gênero Gracilaria, possuem grande importância econômica na produção de ágar, e alguns de seus metabólitos são utilizados no ramo farmacêutico, medicinal e de cosméticos. No entanto, esse gênero pode ser também um bom bioindicador da presença de metais, e os efeitos causados por esses compostos, potenciais biomarcadores. O objetivo presente estudo é verificar os efeitos dos metais cobre (Cu) e cádmio (Cd) em enzimas antioxidantes e de biotransformação na espécie Gracilaria domingensis, e os mecanismos de retenção e detoxificação desses metais. A descrição desses mecanismos visa contribuir com a possibilidade de utilização dessas macroalgas para remediação de ambientes impactados. Para tanto foram desenvolvidos experimentos para definição de valores de IC50 que estabeleceram que os valores de IC50 para o cobre e cádmio para espécie Graciliaria domingensis são 10,6 e 1,05 mg/L, respectivamente. E foram feitos experimentos utilizando as concentrações de cobre de 5,3 e 10,6 mg/L (½ IC50 e IC50) por períodos de 1, 24 e 48 horas. Experimentos com grupos de recuperação, além de experimentos utilizando as concentrações determinadas pelo CONAMA 357/2005 e experimentos de perfil temporal de formação de fitoquelatinas e resposta de biomarcadores após 24, 48, 72 e 96 horas de exposição. As análises das algas expostas demonstraram aumento na atividade da glutationa peroxidase (GPx), glutationa-Stransferase (GST) e ascorbato peroxidase (APx). No entanto, a catalase (CAT) não apresentou atividade detectável, nem mesmo na presença do metal. As análises teste de fitoquelatinas, GSH e GSSG foram inconclusivas, porém os novos testes realizados com concentrações legisladas e relativas ao IC50 mostraram alterações significativas nos níveis de GSSG e GSH para exposição ao cobre, no entanto, o grupo tratado com cádmio foi o único que apresentou fitoquelatinas detectáveis. A espécie Gracilaria domingensis tem demonstrado potencial como organismos bioindicador e os biomarcadores estão fornecendo resultados promissores. / In the last years great importance are being dedicated to the research of metals because of their environmental impact, persistence and the possibility of bioacummulation and biomagnification. The large amount of effluents produced by urban, industrial, agricultural and mining activities among others affect particularly the coastal areas. In this context, the algae which compose the basis of the foodweb, and have the capacity to stock metals decreasing their availability in the environment and therefore to other species inhabiting the area. Such characteristic make the algae a feasibly economic and ecological alternative to be used in bioremediation approaches. Macroalgae belonging to the genus Gracilaria, possess already an economical importance in the production of agar and, some of its metabolites are commonly used in the pharmaceutical industry. The organisms of this genus can also be an indicator of the metal presence in the environment and the effects caused by these compounds potential biomarkers. The objective of this project is to assess the effect of copper (Cu) and cadmium (Cd) on antioxidant or biotransformation enzymes in the algae Gracilaria domingensis and also the mechanisms of retention and detoxification of these metals. The description of these mechanisms can contribute to further use this macroalgae to bioremediation processes. Experiments established the IC50 of copper and cadmium in Gracilaria domingensis at 10.6 and 1.05 mg. L-1, respectively. Experiments using the copper\'s concentrations 5.3 and 10.6 mg. L-1 (½ IC50 and IC50) for 1, 24 and 48 h of were performed. Besides experiments with recovery groups, experiments using CONAMA 357/2005 concentration and experiment with different times of exposure (24, 48,72 and 96 hours) to understand better when phytochelatins starts to be produced and a profile of biomarkers The analysis of exposed algae to copper demonstrated an increased activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST) and ascorbate peroxidase (APx). Interestingly, the catalase (CAT) activity was not detected even though in the presence of metal. Other experiments using concentration determined by CONAMA and IC50 was performed, as well experiments using recovery groups, and a temporal profile, to see the results for 24, 48, 72 e 96 hours of exposure. The analysis of phytochelatine, GSH and GSSG test were inconclusive and new conducted tests with CONAMA\'s and IC50 concentration showed significant alterations in the levels of GSSG e GSH for the samples exposed to copper, however, only the group treated with cadmium demonstrated detectable levels of phytochelatin. The species Gracilaria domingensis has been demonstrating the potential as a bioindicator organism and the biomarkers are producing promising results.
177

Early characterisation of neurodegeneration with high-resolution magnetic resonance elastography

Hiscox, Lucy Victoria January 2018 (has links)
This thesis contributes to recent interest within medical imaging regarding the development and clinical application of magnetic resonance elastography (MRE) to the human brain. MRE is a non-invasive phase-contrast MRI technique for measurement of brain mechanical properties in vivo, shown to reflect the composition and organisation of the complex tissue microstructure. MRE is a promising imaging biomarker for the early characterisation of neurodegeneration due to its exquisite sensitivity to variation among healthy and pathological tissue. Neurodegenerative diseases are debilitating conditions of the human nervous system for which there is currently no cure. Novel biomarkers are required to improve early detection, differential diagnosis and monitoring of disease progression, and could also ultimately improve our understanding of the pathophysiological mechanisms underlying degenerative processes. This thesis begins with a theoretical background of brain MRE and a description of the experimental considerations. A systematic review of the literature is then performed to summarise brain MRE quantitative measurements in healthy participants and to determine the success of MRE to characterise neurological disorders. This review further identified the most promising acquisition and analysis methods within the field. As such, subsequent visits to three brain MRE research centres, within the USA and Germany, enabled the acquisition of exemplar phantom and brain data to assist in discussions to refine an experimental protocol for installation at the Edinburgh Imaging Facility, QMRI (EIF-QMRI). Through collaborations with world-leading brain MRE centres, two high-resolution - yet fundamentally different - MRE pipelines were installed at the EIF-QMRI. Several optimisations were implemented to improve MRE image quality, while the clinical utility of MRE was enhanced by the novel development of a Graphical User Interface (GUI) for the optimised and automatic MRE-toanatomical coregistration and generation of MRE derived output measures. The first experimental study was performed in 6 young and 6 older healthy adults to compare the results from the two MRE pipelines to investigate test-retest agreement of the whole brain and a brain structure of interest: the hippocampal formation. The MRE protocol shown to possess superior reproducibility was subsequently applied in a second experimental study of 12 young and 12 older cognitively healthy adults. Results include finding that the MRE imaging procedure is very well tolerated across the recruited population. Novel findings include significantly softer brains in older adults both across the global cerebrum and in the majority of subcortical grey matter structures including the pallidum, putamen, caudate, and thalamus. Changes in tissue stiffness likely reflect an alteration to the strength in the composition of the tissue network. All MRE effects persist after correcting for brain structure volume suggesting changes in volume alone were not reflective of the detected MRE age differences. Interestingly, no age-related differences to tissue stiffness were found for the amygdala or hippocampus. As for brain viscosity, no group differences were detected for either the brain globally or subcortical structures, suggesting a preservation of the organisation of the tissue network in older age. The third experiment performed in this thesis finds a direct structure-function relationship in older adults between hippocampal viscosity and episodic memory as measured with verbal-paired recall. The source of this association was located to the left hippocampus, thus complementing previous literature suggesting unilateral hippocampal specialisation. Additionally, a more significant relationship was found between left hippocampal viscosity and memory after a new procedure was developed to remove voxels containing cerebrospinal fluid from the MRE analysis. Collectively, these results support the transition of brain MRE into a clinically useful neuroimaging modality that could, in particular, be used in the early characterisation of memory specific disorders such as amnestic Mild Cognitive Impairment and Alzheimer's disease.
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Concentração dos marcadores séricos e presença de sintomas específicos em mulheres com ou sem massas anexiais : Concentration of serum markers and presence of specific symptoms in women with or without adnexal masses / Concentration of serum markers and presence of specific symptoms in women with or without adnexal masses

Moraes, Denise da Rocha Pitta Lima de, 1961- 12 June 2012 (has links)
Orientadores: Sophie Françoise Mauricette Derchain, Luis Otávio Zanatta Sarian / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-11-07T13:25:01Z (GMT). No. of bitstreams: 1 Moraes_DenisedaRochaPittaLimade_D.pdf: 1846599 bytes, checksum: 5c83c44db1103b63041e2ceb928d48d4 (MD5) Previous issue date: 2012 / Resumo: Objetivo: Avaliar a acurácia da mesotelina, CA125, HE4 e índice ROMA na diferenciação de mulheres brasileiras com tumores malignos de ovário daquelas com tumores benignos e ou mulheres saudáveis, e avaliar se os sintomas específicos relatados pelas mulheres podem ser usados em associação à expressão desses marcadores séricos, na diferenciação pré-operatória de neoplasia maligna de ovário. Sujeitos e Métodos: Neste estudo de corte transversal foram incluídas 199 mulheres com massa anexial (67 com tumores malignos e 132 com tumores benignos) e 150 mulheres saudáveis. Todas as mulheres com massa anexial, atendidas no hospital do Departamento de Obstetrícia e Ginecologia da Faculdade de Medicina da UNICAMP, foram convidadas a participar do estudo. Um grupo-controle, de mulheres saudáveis atendidas nos ambulatórios de menopausa e planejamento familiar no mesmo hospital, foi selecionado. Após uma explicação sobre os métodos e objetivo da pesquisa, todas as mulheres responderam o questionário com relação aos sintomas específicos. Foram coletados dados sobre a idade e índice de massa corpórea e sangue periférico para quantificação da mesotelina, o CA125 e a HE4. Foi usado o algoritmo de particionamento recursivo baseado no modelo de regressão linear para verificar a contribuição da idade e de cada marcador sérico no diagnóstico de tumores malignos. Foram comparadas as áreas sob as curvas (AUCs) obtidas através das curvas ROC (Receiver Operator Characteristics) de cada marcador sérico e índice ROMA, para diferenciar mulheres com tumores malignos. Foi calculada a proporção de mulheres com cada um dos 22 sintomas específicos nos grupos com tumores malignos de ovário, tumores benignos e mulheres saudáveis. O sintoma foi considerado positivo quando ocorria mais que 12 vezes ao mês e por até um ano. A proporção de sintomas foi comparada utilizando teste de qui-quadrado ou teste exato de Fischer, quando apropriado. Os 16 sintomas específicos aplicáveis a toda a coorte e para o qual a periodicidade foi verificada foram submetidos à análise pelo Método de Ward para agrupamento hierárquico. Os agrupamentos de sintomas e sintomas isolados identificados foram: abdômen (abdômen inchado e/ou aumento do volume abdominal); dor (dor pélvica, costas e/ou abdominal); pernas inchadas; digestão (estômago cheio e/ou náusea /vômito); alimentação (dificuldade para comer e/ou empachada); sente alguma massa abdominal; diversos (fadiga e/ou dificuldade para respirar); bexiga (urgência em urinar e/ou urinar frequentemente). Foi avaliada a proporção de mulheres com cada agrupamento de sintomas ou sintomas isolados em mulheres com tumores malignos, tumores benignos e saudáveis, através do teste qui-quadrado para tendências. Utilizou-se um algoritmo de particionamento recursivo para verificar a contribuição da idade da mulher, de cada agrupamento de sintomas ou sintomas isolados, estado menopausal, perda de peso e marcadores séricos no diagnóstico de tumores malignos. Resultados: O CA125 foi o marcador sérico com maior capacidade para discriminar mulheres com tumores malignos (p<0,001). Entre as mulheres com tumores benignos e CA125 positivo, a HE4 foi positiva em apenas um caso e a mesotelina foi positiva em outro. Em mulheres com CA125 negativo, a idade, a mesotelina e a HE4 não contribuíram para a diferenciação entre mulheres com tumores malignos, tumores benignos e saudáveis. Em contrapartida, em mulheres com CA125 positivo, a HE4 contribuiu significantemente para detecção de mulheres com tumores malignos (p<0,01). A AUC da mesotelina foi menor que das AUC dos outros marcadores. O ROMA e o CA125 apresentarm melhores AUCs do que o HE4. A proporção de mulheres com cada um dos agrupamentos de sintomas ou sintomas isolados foi significativamente maior em mulheres com tumores malignos, quando comparadas àquelas com tumores benignos e, destas, comparadas com as mulheres saudáveis (p tendência em todas as comparações <0,01). Após a análise multivarida, as associações mais significativas para detecção de tumores malignos de ovário foram as do agrupamento abdômen (p<0,001), expressão do CA125 (p<0,001), agrupamento dor (p=0,01) e perda de peso (p=0,03). Conclusões: Em mulheres com CA125 negativo, a mesotelina e HE4 não contribuíram para detecção do carcinoma de ovário. Entretanto, em mulheres com CA125 positivo, a HE4 contribuiu para diferenciar aquelas com tumores malignos. Em mulheres com tumores malignos de ovário, os sintomas específicos, abdômen e dor foram significantemente mais frequentes. Podem ser utilizados em associação ao CA125 na diferenciação de tumores malignos em mulheres com massa anexial / Abstract: Objective: To evaluate the accuracy of mesothelin, CA125, HE4 and ROMA index in the differentiation of Brazilian women with ovarian malignant tumors from those with benign tumors or healthy women; and to evaluate whether the prevalence of specific self-reported symptoms can be used in association to the expression of serum markers for the preoperative differentiation of ovarian malignant tumors. Study Design: For this cross sectional study, 199 women with adnexal mass (67 with malignant tumors and 132 with benign tumors) and 150 healthy women were included. All women with adnexal masses, attending the hospital of the Department of Obstetrics and Gynecology of the Unicamp School of Medicine were invited to participate in the study. A control group of healthy women attending menopause and family planning clinics at the same hospital were selected. After an explanation about the study research methods and purpose all women answered a survey regarding specific symptoms. There were also collected data on age and body mass index. Peripheral blood was collected for serum measurements of mesotelina, CA125 and HE4. A recursive partitioning algorithm, based on a linear regression model was used to confirm the contribution of age and each of the serum markers to the diagnosis of malignant tumors. Comparison of Area Under the Curve (AUC) obtained through Receiver Operator Characteristics (ROC) curves for each of the serum markers and ROMA index were used to differentiating women with malignant tumors. We next calculated the proportion of women with each of the 22 specific symptoms in the groups of women with ovarian malignant tumors, benign tumors and healthy women. We considered a symptom positive if it occurred more than 12 times per month and for less than one year. The proportions were pairwise compared using chi-square or the Fisher exact test where appropriate. The 16 specific symptoms which applied to the entire cohort and for which the periodicity had been ascertained were further subjected to the Ward's Hierarchical Clustering Method. Clusters of symptoms and isolated symptoms were: abdomen (abdominal bloating and/or increased abdomen size); pain (pelvic, back and/or abdominal pain); leg swelling; digestion (indigestion and/or nauseas /vomiting); eating (unable to eat normally and/or feeling full quickly); able to feel abdominal mass; miscellaneous (fatigue and/or difficulty breathing); bladder (urinary urgency and/or frequent urination). We evaluated the trend in proportion of women with each cluster of symptoms in the groups of women with malignant tumors, benign tumors and healthy women using the chi-squared test for trend in proportions. Another recursive partitioning algorithm was used to confirm the contribution of patient age, clusters of symptoms, menopausal status, weight loss and the serum markers to the diagnosis of malignant tumors Results: CA125 was the serum marker that had the greatest capacity to discriminate women with malignant tumors (p<0.001). Among the women with benign tumors and positive CA125, HE4 was positive in only one case and mesothelin in another case. In women with negative CA125 neither age nor mesothelin nor HE4 contributed any further to the differentiation between women with malignant, tumors benign tumors and healthy women. In contrast, for women with positive CA125, HE4 contributed significantly to the detection of women with malignant tumors (p<0.01). The AUC for mesothelin was smaller than that for all the other curves, and ROMA and CA125 had better AUC than HE4. The proportion of women with each of the clusters of symptoms and isolated symptoms decreased significantly from the group of women with malignant tumors to that with benign tumors and from this group to the healthy women (p for trends in all comparisons= <0.01). After a multivariate analysis the association that contributed the most to the detection of malignant ovarian tumors was that of the abdomen cluster (p<0.001), CA125 expression (p<0.001), pain cluster (p=0.01) and weight loss (p=0.03). Conclusion: In women with negative CA125 neither mesothelin nor HE4 contributed to detect ovarian carcinoma. HE4 was helpful to differentiate malignant tumors when CA125 is positive. Specific symptoms, abdomen and pain were significantly higher in women with malignant ovarian tumors and may be used along with the CA125 to select women with ovarian malignancy among those with adnexal masses / Doutorado / Oncologia Ginecológica e Mamária / Doutora em Ciências da Saúde
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Cistatina C e taxa de filtração glomerular em cirurgia cardíaca com circulação extracopórea /

Felicio, Marcello Laneza. January 2010 (has links)
Resumo: A lesão renal aguda (LRA) apresenta uma alta incidência em pacientes submetidos à cirurgia cardíaca. O comprometimento da função renal está associado ao aumento de complicações pós-operatórias e diminuição da sobrevida. O sucesso de estratégias de tratamento da LRA depende do diagnóstico e intervenção precoce, assim como o conhecimento dos fatores de risco relacionados. O desenvolvimento da LRA é um processo complexo e multifatorial. A lesão renal oculta, consequente à aterosclerose, ao diabetes e à hipertensão arterial sistêmica, pode ser agravada por diversos fatores relacionados ao pré, intra e pós-operatórios. Imprescindível para realização de grande parte das cirurgias cardíacas, a circulação extracorpórea ainda representa um importante fator de agressão renal. A função renal geralmente é avaliada através da dosagem dos níveis séricos de creatinina. Apesar de ser um método amplamente utilizado, a análise da creatinina apresenta suas limitações, o que motiva a procura de novos métodos de diagnósticos e acompanhamento da LRA. Com isso, novos biomarcadores renais têm sido estudados, como a cistatina C, NGAL (neutrophil gelatinase associated lipocalin), interleucina 18 e KIM-1 (kidney injury molecule-1). O objetivo desta revisão é avaliar a importância da LRA como complicação da cirurgia cárdica, assim como discutir seus fatores de riscos e métodos diagnósticos / Abstract: Acute kidney injury (AKI) has a high incidence in cardiac surgery patients. Renal function compromise is associated to an increase in postoperative complications and reduced survival. Success strategies for treating AKI depend on early diagnosis and intervention, as well as knowledge of the associated risk factors. AKI following cardiac surgery is a complex multifactor process. Hidden renal lesion, due to atherosclerosis, diabetes, and systemic arterial hypertension, can be aggravated by different pre, intra, and postoperative factors. Despite being indispensible in many interventions, cardiopulmonary bypass is still an important factor in renal injury. Renal function is generally evaluated through serum creatinine levels. Despite being widely used, creatinine analysis has its limitations which add incentive to looking for new methods of diagnosis and AKI follow-up. This has led to the study of new renal biomarkers such as cystatin C, NGAL (neutrophil gelatinase associated lipocalin), interleukin 18, and KIM-1 (kidney injury molecule-1). The objective of this review is to evaluate the importance of AKI as a cardiac surgery complication, and to discuss its risk factors and methods of diagnosis / Orientador: Antonio Sergio Martins / Coorientador: Pedro Thadeu Galvão Vianna / Banca: Marcos Augusto de Moraes Silva / Banca: Luis Cuadrado Martin / Doutor
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Determinação de um perfil de marcadores associados às desordens neurocognitivas em indivíduos portadores de HIV-1 / Determination of a marker\'s profile associated with neurocognitive disorders in HIV-1 individuals

Ana Carolina Soares de Oliveira 13 March 2018 (has links)
Apesar da introdução da HAART, formas leves de Transtornos Neurocognitivos Associados ao HIV (HAND) permanecem altamente prevalentes, afetando metade de todos os indivíduos infectados. A inflamação sistêmica e localizada induzida pelo HIV é considerada um dos mecanismos da HAND, e embora muitos biomarcadores potenciais tenham sido estudados, até o momento nenhum deles provou ser útil na prática clínica. Portanto, o objetivo desse trabalho foi investigar os níveis de biomarcadores de ativação celular, neurodegeneração e virológicos, no líquido cefalorraquidiano (CSF), e também marcadores genéticos no sangue, buscando associá-los à presença de HAND. Materiais e métodos: Utilizando um desenho transversal, níveis dos marcadores de ativação celular sCD14, Neopterina, MCP-1, IL-1b, IL-6, TNF-?, CXCL-10, IFN-? e MIP-1?; marcadores neuronais Tau, p-Tau, A?40, A?42 e Neurofilamentos; carga viral de HIV e níveis ApoE foram mensurados em 84 amostras de LCR , e a genotipagem do vírus, bem como a genotipagem da ApoE, foram feitas no sangue de 33 indivíduos infectados pelo HIV com alteração neurocognitiva assintomático (ANI), 15 com alteração neurocognitiva de leve a moderada (MND), 15 com demência associada ao HIV ( HAD), 14 controles infectados pelo HIV (C HIV +) e 7 controles não infectados pelo HIV (C HIV-). Os dados clínicos também foram avaliados. Resultados: O parâmetro de idade diferiu estatisticamente entre os grupos, por isso foi ajustado para análise posterior. Os controles HIV+ e o grupo HAND estavam todos sob HAART e aproximadamente 96% deles apresentaram carga viral plasmática e liquórica suprimidas. Os marcadores de neurodegeneração não diferiram estatisticamente entre os grupos. No entanto, os marcadores de ativação celular IFN-gama, IL-1beta e sCD14, juntamente com a ApoE, mostraram diferenças significativas. A análise discriminatória revelou que ApoE e IL-1? juntos possuem maior poder discriminatório para diferenciar o grupo HAND dos controles HIV+. A IL-1b mostrou um aumento progressivo no declínio cognitivo, enquanto os níveis de ApoE mostraram-se mais elevados nos controles HIV+, grupo que também teve a maior porcentagem de genótipo ?4. sCD14 por sua vez mostrou-se elevado no grupo HAND, enquanto IFN-? apresentou queda. Conclusão: Os resultados reforçam o conceito de que a elevação da regulação das citocinas pró-inflamatórias, como sCD14 e IL-1beta, pode desempenhar um papel na patogênese da HAND, mesmo nos pacientes com supressão viral.Em contrapartida, nenhum marcador de neurodegeneração apresentou diferença estatística entre os grupos. É possível que as diferenças encontradas em relação a ApoE nos grupos, tanto tem termos de regulação como a presença do genótipo e4, indique algum mecanismo compensatório, que poderia resultar em um fator protetor contra HAND, portanto deve ser melhor estudado. / Despite the introduction of HAART, mild forms of HIV-associated Neurocognitive Disorders (HAND) remain highly prevalent, affecting half of all infected individuals. Systemic and localized inflammation induced by HIV is considered to be one of the mechanisms of HAND, and although many potential biomarkers have been studied, none of them have proven to be useful in clinical practice. Therefore, the objective of this study was to investigate the levels of biomarkers of cellular activation, neurodegeneration and virological, in the cerebrospinal fluid (CSF), as well as genetic markers in the blood, seeking to associate them with the presence of HAND. Materials and methods: Using a cross-sectional design, levels of the cell activation markers sCD14, Neopterin, MCP-1, IL-1b, IL-6, TNF-?, CXCL-10, IFN-? and MIP-1?; neuronal markers Tau, p-Tau, A?40, A?42 and Neurofilaments; HIV viral load and ApoE levels were measured in 84 CSF samples, and virus genotyping and ApoE genotyping were done in the blood of 33 HIV-infected individuals with asymptomatic neurocognitive impairment (ANI), 15 with neurocognitive impairment (MND), 15 with HIV-associated dementia (HAD), 14 HIV-infected controls (C HIV +), and 7 non-HIV-infected controls (C HIV-). Clinical data were also evaluated. Results: The age parameter differed statistically between the groups, so it was adjusted for later analysis. HIV + controls and HAND group were all under HAART and approximately 96% of them had suppressed plasma and CSF viral load. Neurodegeneration markers did not differ statistically between the groups. However, the cell activation markers IFN-gamma, IL-1beta and sCD14, along with ApoE, showed significant differences. Discriminatory analysis revealed that ApoE and IL-1? together have greater discriminatory power to differentiate HAND group from HIV + controls. IL-1b showed a progressive increase in cognitive decline, while ApoE levels were higher in HIV + controls, which also had the highest percentage of ?4 genotype. sCD14 in turn showed to be elevated in the HAND group, while IFN-? showed decrease. Conclusion: The results reinforce the concept that increased regulation of proinflammatory cytokines, such as sCD14 and IL-1beta, may play a role in the pathogenesis of HAND, even in patients with viral suppression. On the other hand, no neurodegeneration marker presented statistical difference between groups. It is possible that the differences found regarding ApoE in the groups, both in terms of regulation and the presence of the e4 genotype, indicate some compensatory mechanism, which could result in a protective factor against HAND, so it should be better studied.

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