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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.
21

Avaliação imunoistoquimica de celulas mioepiteliais no diagnostico diferencial de lesões benignas e malignas da mama / Immunohistochemical assessment of myoepithelial cells in the differential diagnosis of benign and malignant lesions of the breast

Schenka, Natalia Guimarães de Moraes 30 June 2006 (has links)
Orientador: Jose Vassalo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T05:09:42Z (GMT). No. of bitstreams: 1 Schenka_NataliaGuimaraesdeMoraes_D.pdf: 3809756 bytes, checksum: d4d7db8aeacfcd3c285cdee5b7c0a182 (MD5) Previous issue date: 2006 / Resumo: O sistema ductal da mama é revestido por duas camadas de células: uma constituída de células epiteliais luminais e outra de células mioepiteliais (CME). A identificação das CMEs é de grande importância na rotina em patologia cirúrgica, já que estas estão presentes em lesões benignas e geralmente ausentes nas malignas. Contudo, esta identificação morfológica (i.e., à hematoxilina-eosina) pode tornar-se difícil, sendo necessários marcadores imunoistoquímicos mioepiteliais. Até o momento, nenhum marcador mostrou-se, isoladamente, sensível e específico o bastante para auxiliar de maneira fidedigna em dilemas diagnósticos específicos, especialmente em: (1) lesões esclerosantes benignas vs. carcinoma tubular e (2) neoplasias papilíferas. No presente trabalho, dois novos marcadores mioepiteliais (p63 e CD10) foram testados e comparados com marcadores tradicionalmente empregados em patologia cirúrgica (1A4 e calponina). No primeiro dilema diagnóstico, foram estudados 10 casos de adenose esclerosante, 10 casos de cicatriz radiada e 10 casos de carcinoma tubular. Todos os marcadores demonstraram expressão nas CMEs de todas as lesões benignas e foram consistentemente negativos nos casos de carcinoma tubular, porém, p63 e CD10 mostraram maior especificidade. Os marcadores tradicionais mostraram positividade em células estromais em todos os casos de carcinoma tubular, sendo que esta reação-cruzada poderia causar problemas de interpretação ao simular uma camada de CMEs em quatro casos. Contudo, 1A4 mostrou uma positividade mais intensa e reprodutível nas CME. Concluímos, assim, que p63 e CD10 devem ser usados como anticorpos complementares ao 1A4 na distinção entre lesões esclerosantes benignas e carcinoma tubular da mama. No estudo das neoplasias papilíferas, foram avaliados 20 casos incluindo papilomas, papilomas atípicos e carcinomas papilíferos, além do tecido mamário normal adjacente. Todos os marcadores foram difusamente positivos no tecido mamário normal e papilomas, indicando sensibilidades semelhantes na identificação de CME. Uma positividade intensa foi encontrada em 100% dos casos corados para 1A4 e CD10, mas em apenas 76% e 60,5% dos corados para calponina e p63, respectivamente, sendo as diferenças estatisticamente significantes (p<0.05). Este dado sugere que os dois primeiros são tecnicamente mais reprodutíveis. Os marcadores mais específicos foram o p63 e CD10, mostrando reação-cruzada com células estromais em 0 e até 33% dos casos, respectivamente. Já os marcadores 1A4 e calponina mostraram reação-cruzada difusa em todos os casos. O CD10 mostrou uma combinação de uma maior especificidade e reprodutibilidade, com uma boa sensibilidade. Apesar de ser o mais específico, o p63 apresentou a menor sensibilidade e a impressão de uma camada de CMEs variavelmente interrompida (mesmo em tecido normal e lesões benignas), o que poderia causar problemas de interpretação. Além disto, o 1A4 mostrou-se também neste contexto, como o mais reprodutível tecnicamente. Assim sendo, no dilema diagnóstico das neoplasias papilíferas, defendemos o uso combinado do marcador CD10 com o 1A4. Em resumo, apesar de variarem em acurácia diagnóstica quando comparados entre si e com marcadores tradicionais, na dependência do dilema considerado, os novos marcadores testados neste trabalho parecem promissores no diagnóstico diferencial de lesões benignas e malignas da mama / Abstract: The myoepithelial cell (MEC) layer is usually present and continuous in normal breast tissue/benign lesions, and discontinuous to absent in atypical/malignant counterparts. Identifying MECs can be difficult on morphological grounds alone and currently relies on immunomarkers. So far, this detection has been carried out using antibodies such as alpha-smooth muscle actin (1A4) and calponin, but no immunomarker has proved to be accurate enough to identify MECs, particularly in specific diagnostic dilemmas such as: (1) benign sclerosing lesions vs. tubular carcinoma and (2) papillary neoplasms. The specificity of these markers has been questioned because they may be expressed in stromal myofibroblasts and vascular smooth muscle. Two novel myoepithelial markers have been described: the nuclear protein p63 and the surface antigen CD10. In the present study, we assessed the use of p63 and CD10 in comparison to the traditional markers in the specific diagnostic dilemmas specified above. In the first diagnostic problem, we studied 30 cases including sclerosing adenosis, radial scars and tubular carcinomas. All markers were expressed in MECs of all benign lesions and negative in all cases of tubular carcinoma. p63 and CD10 were mostly confined to MECs and thus more specific. Stromal positivity for 1A4 was present in all cases of tubular carcinoma and was misleading in 4 cases, as it simulated a MEC layer around malignant tubules. However, 1A4 was consistently more intensely expressed and thus more technically reproducible than the novel markers. So, we concluded that p63 and CD10 should be used as a complement to 1A4 in distinguishing benign sclerosing lesions from tubular carcinoma of the breast. Concerning the other diagnostic dilemma, we studied 20 cases of papillary neoplasms (including benign papillomas, atypical papillomas and papillary carcinomas), and adjacent normal breast tissue. All markers were diffusely positive in all samples of normal tissue and benign papillomas indicating similar sensitivities in the identification of MECs. Intense positivity was found in 100% of the cases stained with 1A4 and CD10, but in only 76% and 60,5% of those stained with calponin and p63, respectively; the differences were statistically significant (p<0.05), suggesting that the former two rendered more reproducible results. The most specific markers were p63 and CD10 which showed cross-reactivity in 0% and in up to 33% of the cases, respectively. 1A4 and calponin showed diffuse cross-reactivity in all cases. CD10 seems to combine the highest specificity and reproducibility with a good sensitivity. In spite of being the most specific, p63 was the least sensitive, also giving the impression of a discontinuous MEC layer even in normal tissue/benign lesions, which could potentially cause diagnostic problems. Moreover, in this context, 1A4 proved to be the most reproducible. Thus, a minimum panel for immunodetection of MEC to assess papillary lesions should include both markers. In conclusion, in spite of the variable accuracy depending on the diagnostic dilemma considered, the novel markers seem to be promising tools in the differential diagnosis between benign and malignant lesions of the breast / Doutorado / Anatomia Patologica / Doutor em Ciências Médicas
22

Estudo de Danos Oxidativos Espontâneos no DNA de Pacientes com Lesões Malignas e Benignas de Mama. / Spontaneous Oxidative Damage in DNA of Patients with Malignant and Benign Breast Lesions.

Fernanda Paula de Carvalho 04 November 2011 (has links)
O estresse oxidativo é um dos principais responsáveis pela produção de danos espontâneos no DNA, os quais podem levar à origem de diversas neoplasias, inclusive câncer de mama (CM). Além disso, dentre os diversos fatores de risco já estabelecidos para a ocorrência do CM em mulheres, como idade, hormônios, dieta e fatores genéticos, alguns tipos de lesões benignas mamárias também aparecem como importantes elementos predisponentes. Dessa forma, a pesquisa de genes envolvidos com a produção ou reparo de danos oxidativos, bem como o estudo de elementos bioquímicos relacionados à proteção antioxidante em pacientes com lesões malignas e benignas de mama são fundamentais para o entendimento do mecanismo geral que conduz ao estresse oxidativo no CM. Os objetivos deste estudo foram determinar a frequência dos polimorfismos Ser326Cys hOGG1 e Arg38Trp AHCY pela técnica de PCR-RFLP; avaliar os níveis sanguíneos de folato, vitamina B12 e glutationa peroxidase (GSH-Px); examinar o grau de lesões oxidativas espontâneas no DNA pelo Teste do Micronúcleo (MN), Índice de Divisão Nuclear (IDN) e Ensaio Cometa em linfócitos; e por fim, verificar se os polimorfismos e os elementos bioquímicos estudados exercem influência sobre tais danos oxidativos. Foram coletadas amostras de sangue periférico de 55 voluntárias sadias, 10 pacientes com adenose esclerosante (AE) e 54 pacientes com carcinoma ductal invasivo (CDI) não tratadas. Os polimorfismos foram analisados em todas as amostras. As análises bioquímica e citogenética foram realizadas numa sub-amostra composta por 21 mulheres sadias, 10 pacientes com AE e 14 pacientes com CDI. No Ensaio Cometa foi aplicada a endonuclease OGG1 para detecção de danos oxidativos. Não foi observada relação entre os alelos Ser326Cys hOGG1 e Arg38Trp AHCY e o risco de CM. O número de indivíduos portadores do alelo Arg38Trp AHCY foi insuficiente para as demais análises. Não houve deficiência ou excesso de folato e vitamina B12 entre as voluntárias. Pacientes com CDI apresentaram níveis de GSH-Px e frequência de MNs significativamente maiores do que mulheres sadias. Não houve associação entre o grau de danos espontâneos no DNA e risco de CM. O alelo Ser326Cys hOGG1 não interfere na produção de lesões espontâneas no DNA. O folato e a vitamina B12, em níveis normais, podem provocar instabilidade genômica em pacientes com AE. / Oxidative stress is one of the most important generators of DNA damage, which can lead to carcinogenesis of many cancer types, including breast cancer (BC). Several risk factors were established for occurrence of BC in women, such as age, hormones, diet and genetic factors, however, certain types of benign breast lesions also appear as important predisposing factors. Thus, the search for genes involved in production and repair of oxidative damage, as well as the study of biochemical elements related to the antioxidant protection in patients with malignant and benign breast lesions are fundamental for understanding the general mechanism leading to oxidative stress in the BC. The aims of this study were to determine the frequency of Ser326Cys hOGG1 and Arg38Trp AHCY genetic polymorphisms by PCR-RFLP to investigate their association with BC susceptibility; evaluate folate, vitamin B-12 and glutathione peroxidase (GSH-Px) blood levels; examine the extension of spontaneous oxidative damage in DNA by Micronucleus Test (MN), Nuclear Division Index (NDI) and Comet Assay with lymphocytes; and finally, verify if polymorphisms and biochemicals investigated may influence on oxidative damage. Peripheral blood samples of 119 volunteers were collected: 55 healthy women, 10 patients with sclerosing adenosis (SA) and 54 untreated patients with invasive ductal carcinoma (IDC). Molecular analysis was performed in all samples. Biochemical and cytogenetic analysis were performed on a sub-sample of 45 individuals comprised 21 healthy women, 10 AE patients and 14 ICD patients, chosen at random from the total samples. In Comet Assay, endonuclease OGG1 was applied to detect oxidative damage. No relationship was found between Ser326Cys hOGG1 and Arg38Trp AHCY alleles and risk for BC. The number of individuals carrying the allele Arg38Trp AHCY was insufficient for further analysis. There was no deficiency or excess in folate and vitamin B12 levels among the volunteers. GSH-Px levels and frequencies of MNs were significantly higher in ICD patients than healthy women. There was no association between the degree of spontaneous DNA damage and risk for BC. Ser326Cys hOGG1 allele does not interfere on production of spontaneous DNA lesions. Normal levels of vitamin B12 and folate may cause genomic instability in AE patients.
23

Elevated IgG4 is associated with higher risk for cholangitis, cirrhosis, ERCP and liver-transplantation among patients with primary sclerosing cholangitis

Carlsson, Jennifer January 2022 (has links)
Primary sclerosing cholangitis (PSC) is a rare inflammatory chronic liver disease that causes damage to the intra- and or extrahepatic bile ducts leading to cholestasis. As the disease proceeds the development of cirrhosis and eventually liver failure occurs. This study aims to determine the role of IgG subclasses in the prognosis of PSC and its outcome. A retrospective analysis was performed of 183 patients followed at the Department of Upper Abdominal Diseases at the Karolinska University Hospital. Factors that were analysed were sex, age at PSC diagnosis, total IgG values, IgG subclasses values and events of autoimmune hepatitis (AIH), inflammatory bowel disease (IBD), colectomy, cirrhosis, cholangitis, endoscopic retrograde cholangiopancreatography (ERCP), liver transplantation and cholangiocarcinoma. This study showed that high IgG4 levels were associated with a higher incidence of cirrhosis, liver transplantation, cholangitis and ERCP, while low IgG4 levels were associated with a prior IBD diagnosis. In conclusion, elevated IgG4 levels were associated with a higher occurrence of cirrhosis, cholangitis, ERCP and liver transplantation. It seems that IgG4 could be of importance for outcome prediction in PSC.
24

Farmakoterapi vid primär skleroserande kolangit : En genomgång av läkemedelsprövningar i ljuset av nya rön

Noaksson, David January 2023 (has links)
Primary sclerosing cholangitis (PSC) is a rare chronic liver disease characterized by inflammation and fibrosis of the biliary ducts, resulting in cholestasis and eventually liver failure. No effective treatment is currently available and most patients ultimately require liver transplantation in order to survive. The underlying mechanisms of the disease is poorly understood but a range of hypotheses exist, many of which recognize and grapple with PSC's close relationship with inflammatory bowel disease. Most agree genetics is involved, predisposing for an imbalance in 1) bile acid metabolism, 2) immune response and/or 3) gut microbiota. This literature study aims to describe and elucidate recent progress in the field of pharmacotherapy, as it relates to PSC and our current understanding of the disease. Covered in this study is a total of seven randomized, controlled trials, published between 2015-2022, and available through the medical database/search engine PubMed. Endpoints of particular note are ALP and ELF. ALP, or alkaline phosphatase, is an enzyme found in the liver. Rising levels of ALP in the blood stream is indicative of liver damage. ELF, or Enhanced Liver Fibrosis, is a blood test measuring markers of fibrosis, useful in assessing and staging fibrosis in chronic liver disease. Drugs included in this literature study are aldafermin, cilofexor, fenofibrate, norUrsodeoxicholic acid, obeticholic acid, simtuzumab and vancomycin. With the exception of aldafermin and simtuzumab, all showed promise as ALP reducing agents, in general lowering levels with 15-40 percent. In the case of fenofibrate, a reduction of 65 percent was observed. Of the drugs measured against ELF, only aldafermin produced a statistically significant reduction in fibrosis markers. At the time being it is not entirely clear what to make of the results, due to uncertainties surrounding ALP as a prognostic marker. To what extent ALP predicts transplantation free survival is still a matter of debate. Although considerable efforts have been made to further our understanding of PSC, much is yet to be solved. With regards to pharmacotherapy, the field is experiencing somewhat of a renaissance, showcased by the dozen on-going randomized, controlled trials on a plethora of potential PSC substances. Thus, the search for an effective therapy against PSC goes on.
25

Evaluation of Inhibitory Antibodies against the Muscarinic Acetylcholine Receptor Type 3 in Patients with Primary Biliary Cholangitis and Primary Sclerosing Cholangitis

Wilde, Anne-Christin Beatrice, Greverath, Lena Marie, Steinhagen, Lara Marleen, de Chamorro, Nina Wald, Leicht, Elise, Fischer, Janett, Herta, Toni, Berg, Thomas, Preuss, Beate, Klein, Reinhild, Tacke, Frank, Müller, Tobias 02 June 2023 (has links)
Background: Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) constitute rare chronic inflammatory biliary diseases which likely comprise genetic, environmental and autoimmune factors. Specific inhibitory (auto-) antibodies against the muscarinic acetylcholine receptor type 3 (mAChR3 auto-ab) may contribute to the pathogenesis of chronic biliary inflammation by modulating mAChR3− mediated signaling. Aims: The aim of this study was to analyze the prevalence and relevance of inhibitory mAChR3 auto-ab (mAChR3inh+ auto-ab) in a large cohort of PBC patients from two independent tertiary centers in Berlin and Leipzig in comparison to a large PSC cohort. Baseline parameters and response rates to standard treatment with ursodeoxycholic acid (UDCA) were characterized with respect to the individual mAChR3 auto-ab status. Methods: In total, the study population comprised 437 PBC patients, 187 PSC patients and 80 healthy controls. Clinical and laboratory baseline characteristics were retrieved from medical records. The response to ursodeoxycholic acid (UDCA) therapy after 12 months of treatment was available in 176 PBC and 45 PSC patients. Results: The prevalence of mAChR3inh+ auto-ab was significantly higher among PBC patients (11.2%, 49/437; p = 0.008 vs. healthy controls) and PSC patients (33.6%, 63/187; p < 0.0001 vs. healthy controls) compared to healthy controls (2.5%, 2/80), respectively. PBC patients with mAChR3inh+ auto-ab exhibited significantly higher levels of alkaline phosphatase (ALP) and bilirubin, which constitute established parameters for PBC risk stratification. Moreover, mAChR3inh+ PBC patients tended to show decreased response rates to UDCA therapy compared to PBC patients without mAChR3inh+ auto-ab (mAChR3− PBC). In contrast, PSC patients with mAChR3inh+ auto-ab showed no significant differences in laboratory findings compared to mAChR3 auto-ab negative (mAChR3−) PSC patients. Conclusion: MAChR3inh+ auto-ab might be involved in the pathogenesis and treatment response of chronic biliary inflammation in patients with PBC but not in patients with PSC.
26

Patofyziologie idiopatických střevních zánětů.Vztah k primární sklerózující cholangitidě, transplantaci jater a karcinogenezi. / Pathophysiology of inflammatory bowel disease. Relation to primary scklerosing cholangitis, liver transplantation and carcinogenesis.

Bajer, Lukáš January 2020 (has links)
Inflammatory bowel disease (IBD) represents a group of multifactorial illnesses with increasing incidence worldwide. Crohn's disease (CD) and ulcerative colitis (UC) are the two most thoroughly defined phenotypes of IBD. IBD associated with primary sclerosing cholangitis (PSC) - a progressive biliary disease leading to cirrhosis and liver failure - is considered as specific IBD phenotype (also referred to as 'PSC - IBD') due to its clinical and pathophysiological characteristics. The aim of the experimental part of this thesis was to define specific features of PSC - IBD in the key areas of IBD pathogenesis. These are: microbiota composition, gut - barrier failure, genetic predisposition and aberrant cellular and antibody immune response. Furthermore, the other goals were to describe relation of IBD status and activity to liver transplantation (LTx) and carcinogenesis based on thorough analysis of clinical data in patients under surveillance at the liver transplantation unit. Using the next-generation parallel sequencing technology, we discovered specific bacterial and mycobial features of gut microbiota composition in PSC - IBD which significantly differed from UC and healthy controls recruited from Czech general population. Moreover, we identified numerous seral biomarkers distinguishing CD, UC...

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