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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.
41

Níveis sistêmicos e periodontais de citocinas durante a gestação : correlações e efeito da terapia periodontal

Fiorini, Tiago January 2012 (has links)
A doença periodontal tem sido frequentemente associada ao parto pretermo. A plausibilidade biológica para tal associação baseia-se na hipótese de uma inflamação sistêmica de baixa intensidade de origem periodontal. Entretanto, os estudos de intervenção que investigaram o efeito da terapia periodontal durante a gestação não observaram reduções significativas na incidência de prematuridade. Como diversas citocinas têm sido associadas tanto a doença periodontal quanto ao parto pretermo, cogita-se que elas desempenhem um papel importante na associação observada. Até o presente momento, pouco se sabe a respeito da correlação entre os níveis de citocinas no soro e no fluído crevicular gengival (FCG), assim como do efeito da terapia periodontal sobre esses marcadores de inflamação em gestantes. O objetivo desta tese foi avaliar a relação entre níveis sistêmicos e periodontais de biomarcadores inflamatórios relacionados com a resposta imune periodontal e também com os mecanismos de parto. Também investigou-se o efeito da terapia periodontal sobre os níveis dessas citocinas durante a gestação e 30 dias após o parto. Esta tese é composta por dois estudos que utilizaram uma sub-amostra de mulheres que haviam sido recrutadas para um ensaio clínico randomizado maior que investigou o efeito da terapia periodontal sobre a incidência de prematuridade. Mulheres entre 18-35 anos e com até 20 semanas de gestação foram aleatoriamente alocadas para receber tratamento periodontal não cirúrgico completo até a 24a semana de gestação (grupo teste) ou apenas uma consulta de uma remoção de cálculo supragingival (grupo controle). Dados clínicos e amostras de sangue e FCG foram coletadas no início do estudo, entre 26-28 semanas de gestação e 30 dias após o parto. Quatro sítios periodontais por paciente foram aleatoriamente selecionados para coleta de FCG entre aqueles com maior profundidade de sondagem. Os níveis de IL-1β, IL-6, IL-8, IL-10, IL- 12p70 e FNT-α foram analisados por citometria de fluxo. No estudo 1, investigou-se a correlação e concordância entre os níveis periodontais e sistêmicos dessas citocinas em 100 pacientes, utilizando dados coletados até a 20a semana de gestação. As pacientes apresentaram extensa inflamação e limitada destruição periodontal. A correlação entre os níveis de citocinas no soro e no FCG foi baixa e não significativa, com exceção da IL-12p70 que mostrou uma correlação moderada, porém significativa, entre as duas fontes (r=0.32, p=0.001). Os níveis de citocinas observados no FCG explicaram menos de 10% dos respectivos níveis observados no soro, com exceção da IL-12p70 em que eles foram responsáveis por 23% dos níveis séricos (p=0.0001, r2=0.23). A profundidade de sondagem e o sangramento a sondagem estiveram significativamente associados com os níveis de IL-1β, IL-6 e IL-8 no FCG, mas tiveram efeitos limitados sobre os níveis sistêmicos de todas as citocinas. No estudo 2, comparou-se o efeito da terapia periodontal durante a gestação (n=30) com uma consulta única de remoção de cálculo supragingival (n=30) sobre os níveis periodontais e sistêmicos dessas citocinas durante a gestação e 30 dias após o parto. Após o tratamento, uma redução drástica da inflamação periodontal foi observada no grupo teste, com o percentual de sangramento a sondagem reduzindo de 49.62% para 11.66% dos sítios (p<0.001). A terapia também reduziu significativamente os níveis de IL-1β e IL-8 (p<0.001) no FCG. Entretanto, nenhum efeito significativo do tratamento foi observado em relação aos níveis sistêmicos dessas citocinas. Após o parto, os níveis periodontais de IL-1β no grupo teste permaneceram significativamente menores que no grupo controle, enquanto que nenhuma diferença foi observada em relação aos níveis sistêmicos das outras citocinas avaliadas. Pode-se concluir que os níveis de citocinas no soro e FCG não estão significativamente associados em mulheres com extensa inflamação mas limitada destruição periodontal. Embora a terapia periodontal durante a gestação reduza significativamente o nível de citocinas no FCG, ela parece não ter um impacto considerável sobre os níveis sistêmicos desses biomarcadores. / Periodontal disease has been frequently associated with preterm birth. The biological plausibility for this association relies on the hypothesis of a low-grade systemic inflammation originated from periodontal disease. However, clinical studies that investigated the effect of periodontal therapy during pregnancy did not observe significant reductions in the incidence of prematurity. Several cytokines have been associated with both periodontal disease and preterm birth, and might play a key role in the observed association. To date, little is known about the correlation between serum and gingival crevicular fluid (GCF) cytokine levels, as well as the effect of periodontal therapy on these inflammatory markers in pregnant women. The aim of this thesis was to investigate the relationship between periodontal and systemic levels of inflammatory biomarkers related to periodontal immune response and also with the mechanisms of delivery. We also investigated the effect of periodontal therapy on serum and GCF cytokine levels during pregnancy and 30 days postpartum. This thesis consists of two studies that used a sub-sample of women who had been previously enrolled in a larger randomized controlled trial investigating the effect of periodontal therapy on the incidence of preterm birth. Women aged between 18-35 years and up to 20 weeks of gestation were randomly assigned to receive comprehensive nonsurgical periodontal treatment before the 24th gestational week (test group) or a single appointment of supragingival calculus removal (control group). Clinical data, blood and GCF samples were collected at baseline, between 26-28 weeks of gestation and 30 days postpartum. Four periodontal sites per patient were randomly selected for GCF collection among those with deepest probing depth. IL-1β, IL-6, IL-8, IL-10, IL-12p70 and TNF-α levels were analyzed using a cytometric bead array. In the study one, we investigated the correlation and agreement between periodontal and systemic levels of these cytokines in 100 patients, using data collected until 20 weeks of gestation. Patients presented widespread periodontal inflammation but limited destruction. The correlation between serum and GCF cytokine levels was low and not significant, except for IL-12p70, which showed a moderate but significant correlation between the two sources (r = 0.32, p = 0.001). The GCF cytokine levels observed explained less than 10% of the respective serum levels observed, except for IL-12p70, which was responsible for 23% of serum levels (p = 0.0001, r2 = 0.23). Probing depth and bleeding on probing were significantly associated with IL-1β, IL-6 and IL-8 GCF levels, but had limited effects on systemic levels of all cytokines. In the study two, we compared the effect of periodontal therapy during pregnancy (n=30) or a single appointment for supragingival calculus removal (n=30) on periodontal and systemic levels of these cytokines during pregnancy and 30 days postpartum. After treatment, a remarkable reduction of periodontal inflammation was observed in the test group, with bleeding on probing reducing from 49.62% to 11.66% of the sites (p<0.001). Periodontal therapy also significantly reduced IL-1β and IL-8 GCF levels (p<0.001). However, no significant differences due to therapy were observed regarding systemic levels of these cytokines. After delivery, IL-1β GCF levels in the test group remained significantly lower than in the control group, whereas no difference was observed for systemic levels of any other cytokine evaluated. It can be concluded that serum and GCF cytokine levels are not significantly associated in women with widespread periodontal inflammation but limited destruction. Although periodontal therapy during pregnancy significantly reduces GCF cytokine levels, it seems to have a negligible impact on systemic levels of these biomarkers.
42

Aspects on Head and neck Cancer with special reference to Salivary Gland Tumours and Single Nucleotide Polymorphism

Cederblad, Lena January 2017 (has links)
A thesis on Head and neck cancer focusing on dose planning, salivary gland carcinoma and Single nucleotide polymorphism. For dose planning PET/CT (Positron emissions tomography/computed tomography) with tracer gave more precise information in comparison dose planning with CT. More primary tumours and metastases were found with the acetate tracer than with glucose tracer. Acetate PET/CT also showed larger volume of tumours attributed to lipid metabolism. In a retrospective study salivary gland cancer 5-year overall survival (OS) was 53 %. Salivary gland carcinoma consists of many histopathological groups, the two largest groups being mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ASCC). For ACC, having the best 5-year OS, it was 70 percent. Facial palsy, advanced stage disease, lymph node metastases worsened prognosis. ACC and polymorphous low grade carcinoma (PLGA) expressed c-myc and cyclin D1 to a larger extent than MEC. In squamous cell carcinoma of the head and neck we examined the occurrence of Single Nucleotide polymorphism, SNP. We found that the SNPs in male and female patients differed from each other. In male patients the SNPs were associated with immune response while in female patients the association was to SNPs concerning inflammation. This means that different pathways were engaged in cancer development for men and women. We also found that the SNPs in patients were different from those expressed in the healthy controls.
43

[pt] MODELAGEM DE UM CICLO ORGÂNICO RANKINE COM RECUPERAÇÃO DE CALOR DE REJEITO A BAIXA TEMPERATURA / [en] SIMULATION MODEL FOR A LOW GRADE WASTE HEAT RECOVERY ORGANIC RANKINE CYCLE

OSCAR JUAN PABLO RODRIGUEZ MEJIA 09 November 2021 (has links)
[pt] A presente dissertação trata do estudo de sistemas de potência baseados em ciclos Rankine orgânicos (ORC – Organic Rankine Cycle) acionados por energia térmica de rejeito. O objetivo é descrever mediante a simulação numérica um ciclo Rankine orgânico, dimensionar os trocadores de calor para o ciclo proposto e aplicar o conceito para sistemas de trigeração. Um modelo termodinâmico simples é apresentado, relacionando as características termodinâmicas do ciclo Rankine orgânico àquelas da corrente com rejeito térmico (como, por exemplo, vazão mássica, capacidade térmica e temperaturas de operação). A seguir, o método de multi-zonas, ou de fronteira móvel, é aplicado aos trocadores de calor do ciclo, condensador e caldeira, para dimensioná-los às condições do efluente de rejeito térmico. Na escolha do tipo de trocador de calor para a caldeira, é feita a distinção quanto à natureza do efluente, se gasoso ou líquido. No primeiro caso empregam-se trocadores de tubo e aleta e, no segundo, trocadores de placas. A solução numérica do sistema de equações algebraicas e obtida através de um programa computacional escrito em FORTRAN. São também estudados novos fluidos de trabalho de menor impacto ambiental e os resultados apresentados fazem uma comparação com fluidos de uso tradicional. As propriedades termodinâmicas e de transporte dos fluidos considerados foram obtidas usando o programa REFPROP 9.0 do NIST. Finalmente, o conceito do ciclo Rankine orgânico é aplicado a sistemas de trigeração, caracterizados pela produção simultânea de eletricidade, aquecimento e refrigeração. / [en] The present dissertation addresses the study of power generation systems based on organic Rankine cycles (ORC) driven by waste thermal energy (heat). A simple thermodynamic model is presented, relating the thermodynamic characteristics of the organic Rankine cycle to those of the waste heat flow (for instance: mass flow, thermal capacity and operation temperatures). Furthermore, the multi-zone, or movable boundary method is applied to the heat exchangers of the cycle, boiler and condenser, in order to size them for the waste heat flow conditions. In choosing the type of heat exchanger for the boiler, the distinction is made on the nature of the waste heat, either gaseous or liquid. New working fluids for the cycle, of less environmental impact, are studied. For the first case, tube and fin heat exchangers are considered, and in the second, plate heat exchangers. Finally, the concept of the organic Rankine cycle is applied to trigeneration systems, characterized by the simultaneous production of electricity, heating and cooling.
44

Caractérisation moléculaire des tumeurs cérébrales circonscrites de l'enfant / Molecular caracteristics of low grade pediatric brain tumors

Padovani, Laëtitia 05 April 2013 (has links)
La classification OMS des tumeurs cérébrales de l'enfant distingue les tumeurs gliales des tumeurs glioneuronales, les gliomes circonscrits des infiltrants. Elle représente le meilleur indicateur pronostic mais se heurte pourtant à des limites de reproductibilité. Pour mieux préciser le diagnostic, mieux définir des sous-groupes de pronostic différent, et mieux orienter le thérapeutique, nous avons recherché les profils moléculaires de 108 tumeurs cérébrales circonscrites de l'enfant : astrocytome pilocytique (PA), tumeurs neuroépithéliales dysembryoplasiques (DNT), xanthoastrocytomes pléïomorphes (PXA) et gangliogliomes (GG). Aucune différence n'est retrouvée entre les gliomes corticaux de grade II (GC) et les DNT concernant IDH1 et 2, TP53 et la délétion1p19q. Les DNT non spécifiques et les GC partagent le même profil incluant CD34 et la mutation V600E de BRAF dans 50% des cas. Le PXA exprime la mutation V600E de BRAF dans plus de 50 % des cas et se rapproche du groupe des tumeurs glioneuronales. Concernant le PA, nous confirmons le caractère péjoratif de la topographie hypothalamo-chiasmatique, de l'histologie pilomyxoide, de l'âge inférieur à 36 mois et de l'exérèse partielle. A l'opposé des tumeurs infiltrantes qui appartiendraient au groupe " histones dépendantes", les tumeurs circonscrites pourraient être regroupées sous le terme "MAPKinases dépendantes". On y distinguerait alors les tumeurs avec fusion KIAA1543-BRAF de celles avec mutation V600E de BRAF. Ce travail a permis de mieux caractériser les tumeurs gliales et glioneuronales de l'enfant, reposant sur le transfert en routine de marqueurs moléculaires simples. / The OMS classification for pediatric brain tumors includes glial tumors and mixed glial and glioneuronal tumors, diffuse and no diffuse glioma. All strategic decision making are based on this current classification but it drives to some limits of diagnosis reproductibility.The goal of our study was to define molecular profils for low grade no diffuse pediatric brain tumors including pilocytic astrocytoma (PA), dysembryoplasic neuroepithelial tumor (DNT), pleiomorphic xanthoastrocytoma (PXA) and benign gangliogliome (GG), to improve the quality of diagnosis, define different subgroups with different prognosis and then to improve treatment strategy decision making.No molecular difference was found between cortical grade II glioma (GC) and DNT regarding IDH1 and 2 TP53 alterations and 1p19q deletion. Similarly 50 % of no specific form of DNT share the same molecular profil with GC with CD34 expression and V600E mutation of BRAF. PXA demonstrated BRAFV600E mutation in 60 % of cases. PXA could then be very close glioneuronal tumors. Finally in PA we confirmed the negative impact of hypothalochiasmatic location, pilomyxoid diagnosis and age lower than 36 months and partial resection. We could work on the elaboration of a new classification and define the group named “Histone dependant” for tumors with histone aberrations and the group named “MAPKinases dependant” for tumors with either KIAA 1543-BRAF fusion or V600E BRAF mutation.In conclusion, this work has led to improve the molecular profil characteristics of glioneuronal tumors of childhood with different easy diagnostic markers that can be used in routine practice, and could potentially replace DNA sequencing.
45

Estudo da expressão imunoistoquímica da proteína galectina-3 associada à -catenina e ciclina D1 em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares / Differential expression of galectin-3, -catenin and cyclin D1 in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands

Ferrazzo, Kivia Linhares 31 October 2008 (has links)
Neoplasias malignas das glândulas salivares são lesões raras e o mecanismo pelo qual esses tumores progridem ainda não está completamente esclarecido na literatura. A galectina-3 é uma proteína multifuncional expressa em uma grande quantidade de tecidos normais, mas que também tem sido associada à progressão tumoral de neoplasias malignas da tireóide, próstata e neoplasias gástricas. Estudos prévios demonstraram que a galectina-3 está também expressa em algumas neoplasias malignas das glândulas salivares como carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade. Recentemente foi sugerido que a superexpressão da galectina-3 controla alterações nos níveis de expressão de alguns reguladores do ciclo celular, dentre eles a ciclina D1. Além disso, outros estudos revelaram que a ciclina D1 é ativada pela -catenina de uma maneira dependente da galectina-3. O objetivo desse trabalho foi comparar a marcação imunoistoquímica nuclear e / ou citoplasmática da galectina-3 no carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau tentando relacioná-la à marcação da -catenina e ciclina D1. Foram realizadas reações de imunoistoquímica para as três proteínas em 15 casos de carcinoma adenóide cístico e em 15 casos de adenocarcinoma polimorfo de baixo grau utilizando-se material parafinado. Para a galectina-3 os carcinomas adenóides císticos apresentaram marcação imunoistoquímica apenas nas células luminais, predominantemente no núcleo. Todos os casos de adenocarcinoma polimorfo de baixo grau revelaram uma marcação predominantemente citoplasmática para essa proteína. Ambos os tumores exibiram intensa marcação citoplasmática e/ou nuclear para a -catenina na maioria dos casos. Não houve imunorreatividade para a ciclina D1 em 14/15 casos de adenocarcinoma polimorfo de baixo grau. Em contraste, os carcinomas adenóides císticos revelaram marcação nuclear específica para a ciclina D1 em 10 de 15 casos estudados em mais de 5% das células neoplásicas e essa marcação estava associada à marcação citoplasmática e nuclear da galectina-3 (p<0,05). Esses resultados sugerem que nos carcinomas adenóides císticos a expressão da galectina-3 pode exercer uma função de proliferação celular e parece estar relacionada à diferenciação celular no adenocarcinoma polimorfo de baixo grau. Além disso, a perda de expressão da galectina-3 no carcinoma adenóide cístico pode estar associada a um comportamento clínico mais agressivo dessa lesão. Embora a -catenina pareça exercer algum papel no mecanismo de carcinogênese dessas duas lesões, ela não parece se ligar à galectina-3 para ativar a ciclina D1. / Salivary gland tumors are uncommon and the mechanism by which malignant tumors progresses is still undefined. In a previous study it was shown that galectin-3 is expressed in malignant salivary gland neoplasms as adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma. Galectin-3 is a multifunctional protein of a group of galactoside-binding lectins expressed in a variety of normal cells, but also has been implicated in tumor progression of some malignancies as thyroid, prostate and gastric cancers. Recently, it has been suggested that galectin-3 may be an important mediator of the -catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, in the present study we aimed to correlate galectin-3 expression, either nuclear or cytoplasmic, with the expression of -catenin (nuclear/cytoplasmic) and cyclin D1 (nuclear) in 15 cases of adenoid cystic carcinoma and in 15 cases of polymorphous low-grade adenocarcinoma. For galectin-3, adenoid cystic carcinomas showed specific staining only in luminal cells, mainly in the nuclei. In the cases of polymorphous low-grade adenocarcinoma, all tumor cells revealed a positive, mostly cytoplasmic, reaction to galectin-3. Both tumors showed intense cytoplasmic/nuclear staining for -catenin in the majority of cases. Cyclin D1 immunoreactivity was not detected in 14 of the 15 polymorphous low-grade adenocarcinomas studied. In contrast, adenoid cystic carcinomas showed specific nuclear staining for cyclin D1 in 10 of 15 cases studied in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in adenoid cystic carcinomas (p<0,05). These results suggest that in adenoid cystic carcinoma galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In polymorphous low-grade adenocarcinoma gal-3 expression seems to be associated with cellular differentiation. In addition, loss of cytoplasmic expression of galectin-3 in adenoid cystic carcinomas may be related to a more aggressive behavior of these lesions. Although -catenin seems to play a role in carcinogenesis, in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.
46

Estudo da imunoexpressão das proteínas C-JUN e JUNB em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares / c-Jun and junB immunoprofile in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands

Rejas, Roberto Anaximandro Garcia 17 July 2008 (has links)
O carcinoma adenóide cístico e o adenocarcinoma polimorfo de baixo grau de malignidade são neoplasmas de glândulas salivares. O carcinoma adenóide cístico pode apresentar-se em glândulas salivares maiores e menores, porém o adenocarcinoma polimorfo de baixo grau de malignidade acomete principalmente as glândulas salivares menores distribuidas na cavidade oral. Ambos os tumores compartilham muitas características comuns, como a alta propensão de invasão perineural e o padrão de infiltracão: sólido, tubular e cribriforme. Mas o carcinoma adenoide cístico e o adenocarcinoma polimorfo de baixo grau são tipos distintos de adenocarcinomas com prognóstico diferente, que ocasionalmente podem resultar em um diágnóstico errado. As proteínas c-jun e junB são membros da familia JUN, capazes de homodimerizar ou heterodimerizar com c-fos ou com outras proteinas bzip. Evidências das funcões específicas das subunidades do AP-1 foram mostradas por cjun e junB, que atúam antagónicamente no controle da transformação celular, diferenciação e expressão do AP-1 dependente do gene alvo. Mas a função de ambos é complexa e pode depender do tipo celular. O objetivo deste estudo foi determinar a expressão imunoistoquímica das proteínas c-jun e junB em 13 casos de carcinoma adenoide cístico e 12 de adenocarcinoma polimorfo de baixo grau de malignidade de glándulas salivares. Espécimes de mucosa normal foram incluídos e evidenciaram forte marcação nuclear e citoplasmática para junB e c-jun respectivamente. No presente estudo, independente da arquitetura histológica, ambos tumores mostraram muitas células tumorais com marcação nuclear e citoplasmática para a proteína c-jun e ausente para a proteína junB. As lesões do adenocarcinoma polimorfo de baixo grau de malignidade expressaram um maior número de células com marcação nuclear quando comparados ao do carcinoma adenoide císticode de mais baixo grau. De acordo com este estudo e com alguns estudos publicados na literatura, a c-jun é expressa em tumores de baixo grau e parece estar mais relacionada à diferenciação celular do que à proliferação celular. / Adenoid cystic carcinoma and polymorphous low grade are salivary gland neoplasms. ACC can arise in both, major or minor salivary glands. However, Polymorphous lowgrade adenocarcinoma, occurs specifically in minor salivary glands dispersed in the oral cavity. They share many common histologic features, as infiltrating solid, tubular and cribiform patterns and also high propensity for perineural invasion. Nevertheless, adenoid cystic carcinoma and polymorphous low grade are distinct types of adenocarcinomas with different prognosis, which occasionally may result in a diagnostic pitfall. C-jun and junB are family JUN members that may form homodimerizes or heterodimerizes with c-fos or other bzip proteins. Evidence for specific functions of AP-1 subunits was shown for c-jun and junB, which act antagonistically to control cell transformation, differentiation and expression of AP-1 depending on the target genes. However, the role of both of them is complex and it depends on cell type. The aim of this study was to determine immunohistochemistry of c -jun and junB expression in 13 cases of adenoid cystic carcinoma and 12 cases of polymorphous carcinoma low-grade adenocarcinoma of salivary glands. Moreover slides of normal mucosa were included and there were strong nuclei and cytoplasmic for junB and c-jun respectly. In the present study, independent of the histologic architecture, in both tumors shown many tumoral cells presented nuclear and cytoplasmic staining of c-jun and were absent to the protein junB. In polymorphous low-grade adenocarcinoma lesions expressed in a greater number cells staining than in the adenoid cystic carcinoma of the most lowgrade. According with this study and with some studies of the literature, the c-jun is expressed in low-grade tumors and seems to be related to cell differentiation more than with cell proliferation.
47

Estudo da expressão imunoistoquímica da proteína galectina-3 associada à -catenina e ciclina D1 em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares / Differential expression of galectin-3, -catenin and cyclin D1 in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands

Kivia Linhares Ferrazzo 31 October 2008 (has links)
Neoplasias malignas das glândulas salivares são lesões raras e o mecanismo pelo qual esses tumores progridem ainda não está completamente esclarecido na literatura. A galectina-3 é uma proteína multifuncional expressa em uma grande quantidade de tecidos normais, mas que também tem sido associada à progressão tumoral de neoplasias malignas da tireóide, próstata e neoplasias gástricas. Estudos prévios demonstraram que a galectina-3 está também expressa em algumas neoplasias malignas das glândulas salivares como carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade. Recentemente foi sugerido que a superexpressão da galectina-3 controla alterações nos níveis de expressão de alguns reguladores do ciclo celular, dentre eles a ciclina D1. Além disso, outros estudos revelaram que a ciclina D1 é ativada pela -catenina de uma maneira dependente da galectina-3. O objetivo desse trabalho foi comparar a marcação imunoistoquímica nuclear e / ou citoplasmática da galectina-3 no carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau tentando relacioná-la à marcação da -catenina e ciclina D1. Foram realizadas reações de imunoistoquímica para as três proteínas em 15 casos de carcinoma adenóide cístico e em 15 casos de adenocarcinoma polimorfo de baixo grau utilizando-se material parafinado. Para a galectina-3 os carcinomas adenóides císticos apresentaram marcação imunoistoquímica apenas nas células luminais, predominantemente no núcleo. Todos os casos de adenocarcinoma polimorfo de baixo grau revelaram uma marcação predominantemente citoplasmática para essa proteína. Ambos os tumores exibiram intensa marcação citoplasmática e/ou nuclear para a -catenina na maioria dos casos. Não houve imunorreatividade para a ciclina D1 em 14/15 casos de adenocarcinoma polimorfo de baixo grau. Em contraste, os carcinomas adenóides císticos revelaram marcação nuclear específica para a ciclina D1 em 10 de 15 casos estudados em mais de 5% das células neoplásicas e essa marcação estava associada à marcação citoplasmática e nuclear da galectina-3 (p<0,05). Esses resultados sugerem que nos carcinomas adenóides císticos a expressão da galectina-3 pode exercer uma função de proliferação celular e parece estar relacionada à diferenciação celular no adenocarcinoma polimorfo de baixo grau. Além disso, a perda de expressão da galectina-3 no carcinoma adenóide cístico pode estar associada a um comportamento clínico mais agressivo dessa lesão. Embora a -catenina pareça exercer algum papel no mecanismo de carcinogênese dessas duas lesões, ela não parece se ligar à galectina-3 para ativar a ciclina D1. / Salivary gland tumors are uncommon and the mechanism by which malignant tumors progresses is still undefined. In a previous study it was shown that galectin-3 is expressed in malignant salivary gland neoplasms as adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma. Galectin-3 is a multifunctional protein of a group of galactoside-binding lectins expressed in a variety of normal cells, but also has been implicated in tumor progression of some malignancies as thyroid, prostate and gastric cancers. Recently, it has been suggested that galectin-3 may be an important mediator of the -catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, in the present study we aimed to correlate galectin-3 expression, either nuclear or cytoplasmic, with the expression of -catenin (nuclear/cytoplasmic) and cyclin D1 (nuclear) in 15 cases of adenoid cystic carcinoma and in 15 cases of polymorphous low-grade adenocarcinoma. For galectin-3, adenoid cystic carcinomas showed specific staining only in luminal cells, mainly in the nuclei. In the cases of polymorphous low-grade adenocarcinoma, all tumor cells revealed a positive, mostly cytoplasmic, reaction to galectin-3. Both tumors showed intense cytoplasmic/nuclear staining for -catenin in the majority of cases. Cyclin D1 immunoreactivity was not detected in 14 of the 15 polymorphous low-grade adenocarcinomas studied. In contrast, adenoid cystic carcinomas showed specific nuclear staining for cyclin D1 in 10 of 15 cases studied in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in adenoid cystic carcinomas (p<0,05). These results suggest that in adenoid cystic carcinoma galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In polymorphous low-grade adenocarcinoma gal-3 expression seems to be associated with cellular differentiation. In addition, loss of cytoplasmic expression of galectin-3 in adenoid cystic carcinomas may be related to a more aggressive behavior of these lesions. Although -catenin seems to play a role in carcinogenesis, in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.
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Estudo da imunoexpressão das proteínas C-JUN e JUNB em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares / c-Jun and junB immunoprofile in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands

Roberto Anaximandro Garcia Rejas 17 July 2008 (has links)
O carcinoma adenóide cístico e o adenocarcinoma polimorfo de baixo grau de malignidade são neoplasmas de glândulas salivares. O carcinoma adenóide cístico pode apresentar-se em glândulas salivares maiores e menores, porém o adenocarcinoma polimorfo de baixo grau de malignidade acomete principalmente as glândulas salivares menores distribuidas na cavidade oral. Ambos os tumores compartilham muitas características comuns, como a alta propensão de invasão perineural e o padrão de infiltracão: sólido, tubular e cribriforme. Mas o carcinoma adenoide cístico e o adenocarcinoma polimorfo de baixo grau são tipos distintos de adenocarcinomas com prognóstico diferente, que ocasionalmente podem resultar em um diágnóstico errado. As proteínas c-jun e junB são membros da familia JUN, capazes de homodimerizar ou heterodimerizar com c-fos ou com outras proteinas bzip. Evidências das funcões específicas das subunidades do AP-1 foram mostradas por cjun e junB, que atúam antagónicamente no controle da transformação celular, diferenciação e expressão do AP-1 dependente do gene alvo. Mas a função de ambos é complexa e pode depender do tipo celular. O objetivo deste estudo foi determinar a expressão imunoistoquímica das proteínas c-jun e junB em 13 casos de carcinoma adenoide cístico e 12 de adenocarcinoma polimorfo de baixo grau de malignidade de glándulas salivares. Espécimes de mucosa normal foram incluídos e evidenciaram forte marcação nuclear e citoplasmática para junB e c-jun respectivamente. No presente estudo, independente da arquitetura histológica, ambos tumores mostraram muitas células tumorais com marcação nuclear e citoplasmática para a proteína c-jun e ausente para a proteína junB. As lesões do adenocarcinoma polimorfo de baixo grau de malignidade expressaram um maior número de células com marcação nuclear quando comparados ao do carcinoma adenoide císticode de mais baixo grau. De acordo com este estudo e com alguns estudos publicados na literatura, a c-jun é expressa em tumores de baixo grau e parece estar mais relacionada à diferenciação celular do que à proliferação celular. / Adenoid cystic carcinoma and polymorphous low grade are salivary gland neoplasms. ACC can arise in both, major or minor salivary glands. However, Polymorphous lowgrade adenocarcinoma, occurs specifically in minor salivary glands dispersed in the oral cavity. They share many common histologic features, as infiltrating solid, tubular and cribiform patterns and also high propensity for perineural invasion. Nevertheless, adenoid cystic carcinoma and polymorphous low grade are distinct types of adenocarcinomas with different prognosis, which occasionally may result in a diagnostic pitfall. C-jun and junB are family JUN members that may form homodimerizes or heterodimerizes with c-fos or other bzip proteins. Evidence for specific functions of AP-1 subunits was shown for c-jun and junB, which act antagonistically to control cell transformation, differentiation and expression of AP-1 depending on the target genes. However, the role of both of them is complex and it depends on cell type. The aim of this study was to determine immunohistochemistry of c -jun and junB expression in 13 cases of adenoid cystic carcinoma and 12 cases of polymorphous carcinoma low-grade adenocarcinoma of salivary glands. Moreover slides of normal mucosa were included and there were strong nuclei and cytoplasmic for junB and c-jun respectly. In the present study, independent of the histologic architecture, in both tumors shown many tumoral cells presented nuclear and cytoplasmic staining of c-jun and were absent to the protein junB. In polymorphous low-grade adenocarcinoma lesions expressed in a greater number cells staining than in the adenoid cystic carcinoma of the most lowgrade. According with this study and with some studies of the literature, the c-jun is expressed in low-grade tumors and seems to be related to cell differentiation more than with cell proliferation.
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'Nexial-topology' situation modelling : health ecology and other general perspectives

Bouchon, Marika, University of Western Sydney, College of Arts, Centre for Social Ecology Research January 2008 (has links)
ABSTRACT: This research generated a formal method for global ‘situation modelling’ of near-critical and critical phenomena. The new paradigms and the construction of mental reality or social spaces do not explain the damaged world we leave to our children and the degeneration of health. The ‘physical’ was explored experimentally through the reputed imperfection of the body in daily living and the ecology of its health. An ‘integral’ methodology allowed combining this with a study of general perspectives in many fields. This theoretical and empirical study was framed according to a third-order logic: (1) The variety and inconsistency of perspectives on the unclear notion of ‘health’ required a generalist (meta-)classification or organising principle applicable in particular to health. The method of ‘perspectival analysis’ is based on the field- and domain-specific vocabularies, number of categories, and image types used in formulating explanation/ experience in each framework, in both scientific and human domains. This theoretical study was (2) grounded in a ‘radical empirical’ study of the effects of nutrition and healing techniques on a low-grade chronic syndrome (not life threatening but connected to stress, inflammation, swelling, tissues wasting). A ‘local-case’ experimental research design (representative of an aspect of health), and new topographic ‘gauging’ techniques were devised to observe small spatial changes (positioning, distortion, distribution). The results and concrete/ practice models led to the same conclusion as the abstract study: all our perspectives on health, body and space, have some underlying systemic form, and have in common two unifying frames – duality and polarisation –, characteristic also of point-set theory derived frameworks. Using them allows ‘circumnavigating’ the essential of all possible perspectives, without becoming lost in their details. However, they leave non-local effects, anomalies (or ’bad behaviour’) and periodical instability unexplained. (3) These were investigated by studying behaviour (irrespective of whether internal or external), and ‘not well understood’ induced health manifestations, and by mapping their topologic properties of small deformation through (a) a ‘local’ cognitive consideration of experience construction, the research process itself, and the intellectual skill of model-making, (b) etymologic studies to track forward semantic developments and perspectival shifts and inversions, (c) a graphic study of the universal symbolic forms in models, traditions, and dreams, tracing them back to ‘world-origin’ models (appearance/occurrence), and shape-icons (mental, cultural), such as tree, ladder, mountain or vortex-vertex spiral. This thesis examines health disturbance, physical distortions and cultural deformations, their usual descriptions as timed changes, and shows how two fundamental parameters of direction and motion (or movement, energy, 'Wind') define geometries of binding, or directional activation (or active projection). These culturo-mental geometries produce generic images of locally induced phenomena, and represent boundary phenomena globally as 'natural' in the spatial-physical world, and as 'hidden' or latent in the human world. Their downside is to introduce systematic instability in our expressions, models of culture/civilisation, as well as in health manifestations. All these are found to be rooted in modelling styles derived from the 'local' geometry of observing – framing – a field in 'perspective', mostly based on vision, audition, and skin surface (touch). These geo-Metries are used to explain and justify in particular the instability and recurrent crises of health in chronic syndromes and ageing, and the ‘badly behaved’ health of childhood and adult females (eg consequences of pregnancy). The conclusion imposed itself that the ‘physical world of humans’ is shaped through critical response and boundaries, and it appears that physical integrity, including sound health, sanity and even safety, cannot be preserved but by conscious alert attention or voluntary practice or effort (eg ‘workout’). Some experiences recounted in this work (some from the literature) led to an opposite presupposition. Three possible logics rule deployments of perspective into flat, spherical, and hyperbolic geometries (a known basis of mathematics). Which is used depends on the ‘local’ state of criticality (sense of urgency, emergency, pressure) of the observing body-brain-‘system’. It correlates with this universally assumed vertical axis, with the exclusive use [instruments too] of the senses of the head and of ‘skin-encapsulated’ derived systemic definitions of ‘the world’ and ‘the observer’ (self or body). These allow localising and attributing properties to one or the other or their combination. However, they can also be considered as undifferentiated properties, ‘non-local’ but governing, of the ‘physical world of humans’ as it is apprehended in daily living, manifesting in a surface-related sense of swelling and gravity. A simple form of geometric topology ‘without hole’ (without discontinuity), here introduced through two cognitive experiments, animations, and images, can describe this. The method of ‘nexial-topology’ produces an ‘animated imaging’ that can be used to model (but not ‘represent’ in word, number, or realistic/ naturalistic images) the situation reaching ‘critical boundary’. It then shows auto-reinforcing self-organisation and auto-destruction in ‘passing’ it. Yet, it can also be used as a ‘native gauging’ expressed in gesture or body posture, related to intuition, instinct, and the rare ‘thinking in image’. As such, it describes approaching ‘critical boundary’ (versus ‘reaching’) as auto-limiting. A crucial finding is that ‘spontaneous’ behaviours (non-induced, non-intended) can ensure the integrity of health under operation in most conditions, and stop extremes. Yet, they are usually deemed meaningless, random or useless, and are systematically suppressed by enculturation and prevented by civilised lifestyles. ‘Nexial-topology’ gives a clear meaning to them, and can model the ‘ease’ of health and of daily living. It gives access to more basic options, with wider effects, more immediate than all our solutions, often ignored because too obvious. For example, ‘global warming’ could be addressed as a non-local property and a deployment into crises to ‘stop’, rather than separate problems of water, resources, heated behaviour, inflammatory and ‘water diseases’. KEYWORDS: Interdisciplinary research, cross-disciplinary methodologies, modal logic, fundamental problem, general relativity, localisation, physicalism, geometric quantization, occurrence, appearance, extension, projection, attribution, distributed, anthropic principle, anthropomorphism, unified, unbounded, left, right, spiral, viral, genetic drift, natural, life, human nature, human pressure, limit, extreme, threshold, validity, value, critical decision making, apperception, child cognition, sense, semantic drift, Four Elements, symbolic inversion. THIS IS A MULTI-MEDIA THESIS. FOR A SITE MAP OF THE NAMES AND DISPLAY ONLINE OF THE 52 FILES OF THIS THESIS, PLEASE CONSULT THE SECTION: ORGANISATION OF THE MULTI-MEDIA MATERIALS IN THIS THESIS, IN THE FRONT PAGES FILE (SOURCE 2), BEFORE THE TABLE OF CONTENTS. / Doctor of Philosophy (PhD)
50

In Search of Prognostic Factors in Grade 2 Gliomas

Ribom, Dan January 2002 (has links)
<p>Grade 2 gliomas are malignant brain tumours affecting otherwise healthy adults. Although the long-term prognosis is poor, many patients are well and may have a high quality of life for several years. There is, however, a large variability in the natural course of the disease which makes it essential to identify patients who might benefit from early surgery or radio-therapy. The aim of the present thesis was to define new and clinically useful prognostic markers that may assist in the initial treatment decision and in patient follow-up.</p><p>A retrospective study of 189 patients with gliomas WHO grade 2 showed no advantage in survival of early tumour resection or radiotherapy, and confirmed that histological subtype and patient age are the most important predictors of survival (I). In 89 patients, the pre-treatment uptake of 11C-methionine (MET) measured with positron emission tomography (PET) was identified as a prognostic marker for survival (II). At the time of tumour progression, irradiated tumours demonstrated signs of a residual radiotherapeutic effect that correlated with the pre-treatment uptake of MET (III). Pre-treatment uptake of MET may, therefore, be important both in predicting the natural course of the disease and the response after treatment. Immunohistochemical staining of 40 tumour samples showed an inverse association between the number of tumour cells expressing platelet-derived growth factor alpha receptor (PDGFRa) and survival (IV). Also, a reduction was observed in the number of receptor-positive cells after malignant transformation, supporting the prognostic value of PDGFRa.</p><p>Lumbar puncture was performed in eight patients with newly diagnosed low-grade gliomas to identify three important growth factors in tumour development. Neither PDGF nor vascular endothelial growth factor (VEGF) were detected in the cerebrospinal fluid (CSF), and fibroblast growth factor 2 (FGF-2) was measurable at extremely low concentrations in two of the patients (V). A proteome screening of the CSF, using two-dimensional gel electrophoresis and mass spectrometry, detected alpha 2-HS glycoprotein at significantly higher concentrations than in a control group (VI). This glycoprotein emerges as a novel substance in glioma research and may be of great interest because of its suggested involvement in the embryonic development of the neocortex.</p>

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