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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.
211

Relação entre a elastância pleural e efetividade da pleurodese no derrame pleural maligno recidivante / Relationship between the success of bedside pleurodesis and pleural elastance in recurrent malignant pleural effusion

Pedro Henrique Xavier Nabuco de Araujo 30 April 2015 (has links)
Introdução: O tratamento para o derrame pleural maligno recidivado tem caráter paliativo, sendo a pleurodese o método mais utilizado. Contudo, nem todos os procedimentos são efetivos, em parte por um encarceramento do pulmão pela pleura visceral espessada que impede o contato entre os folhetos pleurais e subsequente pleurodese efetiva. A elastância pleural reflete o grau de encarceramento da pleura visceral, contudo sua correlação com a efetividade da pleurodese não é bem conhecido. Objetivo: Analisar a correlação entre a elastância pleural e a efetividade radiológica (quantificada por tomografia de tórax) da pleurodese realizada através de cateteres pleurais. Os objetivos secundários deste estudo são: correlacionar a elastância pleural com a qualidade de vida, graus de dispneia e dor após o procedimento, efetividade clínica, complicações e mortalidade. Correlacionar a posição da extremidade do cateter pleural com o sucesso radiológico e clínico da pleurodese. Métodos: Estudo prospectivo com 131 pacientes candidatos a pleurodese por instilação de nitrato de prata ou talco mineral por cateter pleural. As pressões pleurais foram aferidas através de manômetro hidrostático ou de transdutor eletrônico de pressão vascular durante o esvaziamento do líquido e usadas para calcular a elastância pleural, em cm H2O/L. A efetividade radiológica foi avaliada pelos volumes pleurais medidos por tomografias computadorizadas de tórax logo após a drenagem e 30 dias após a pleurodese. A efetividade clínica foi avaliada conforme a necessidade de procedimentos adicionais para controle de sintomas. A qualidade de vida foi avaliada através do questionário geral da OMS. A avaliação da dor foi feita pela quantificação na Escala Visual Analógica de Dor. A análise da dispneia foi realizada através da quantificação da funcionalidade na escala de dispneia do British Medical Research Council. Todos esses questionários foram aplicados antes da drenagem, 30 dias após pleurodese e, então, trimestralmente. Para a análise da segurança dos procedimentos foram considerados os tempos de internação e de drenagem e a ocorrência de complicações. Todos os pacientes foram seguidos até o óbito ou até o término do estudo, em novembro de 2014, registrando as complicações e as datas do óbito para a construção da curva de sobrevida. Resultados: Avaliamos 87 pacientes de um total de 131 recrutados. Não houve diferença entre os volumes pleurais nas duas tomografias realizadas. A efetividade clínica foi observada em 86,20% dos pacientes. Não houve diferença em nenhum dos domínios da qualidade de vida. Encontramos diferenças entre a dispneia e a dor aferidas 30 dias após a pleurodese e antes da drenagem. Complicações ocorreram em 14,94% dos casos. A mediana da sobrevida global foi de 16 meses. Não foram encontradas correlações entre as elastâncias pleurais em 400 ml, 800 ml e total com nenhum dos desfechos radiológicos, clínicos (efetividade clínica, qualidade de vida, dispneia, dor e complicações) ou com a sobrevida dos pacientes. A posição da ponta do cateter pleural não se correlacionou com o sucesso radiológico ou clínico da pleurodese. Conclusões: A elastância pleural não se mostrou, até o presente momento, capaz de predizer os defechos radiológicos, clínicos e a sobrevida em pacientes submetidos a pleurodese / Background: The treatment of recurrent malignant pleural effusion has a palliative purpose. Pleurodesis is the most used method. However, not all the procedures are effective, in part because of the lung entrapment by the visceral pleura, preventing the contact between the pleural surfaces and subsequente effective pleurodesis. The pleural elastance reflects the degree of entrapment of the visceral pleura, but its correlation with the effectiveness of pleurodesis is not well known. Objetive: To evaluate the correlation between pleural elastance and radiological effectiveness (measured by tomography) of bedside pleurodesis. The secondary objectives of this study are: correlating the pleural elastance with quality of life, degree of dyspnea and pain after the procedure, clinical effectiveness, complications and mortality. Evaluate the role of intrapleural position of the pleural catheter in early lung expansion and success of pleurodesis. Methods: Prospective study including 131 patients with recurrent malignant pleural effusion candidates for treatment with bedside pleurodesis with silver nitrate or mineral talc. Pleural pressures were measured through hydrostatic gauge or electronic pressure transducer during emptying of effusion and used to calculate the pleural elastance in cm H2O/L. Pleural volumes measured by CT scans of the chest after drainage and 30 days after pleurodesis were assess the radiological effectiveness. The clinical effectiveness was evaluated as the need for additional procedures to control symptoms. The quality of life was assessed using the WHO general questionnaire. Quantifying the Visual Analog Scale of Pain did pain assessment. Measuring the functionality in the British Medical Research Council dyspnea scale made the analysis of dyspnea. All these questionnaires were applied prior to drainage, 30 days after pleurodesis and then quarterly. Results: We evaluated 87 patients of a total of 131 recruited. There was no difference between the two pleural volumes CT scans performed. The clinical effectiveness was observed in 86.20% of patients. There was no difference in any of the domains of quality of life. We found differences between dyspnea and pain measured 30 days after pleurodesis and before draining. Complications occurred in 14.94% of cases. The median overall survival was 16 months. No correlations between pleural elastance in 400 ml, 800 ml and complete were found with all the imaging, clinical (clinical effectiveness, quality of life, dyspnea, pain and complications) or with patient survival outcomes. The tip of the pleural catheter was not correlated with the radiological or clinical success of pleurodesis. Conclusions: The pleural elastance was not, so far, able to predict the radiological outcomes, clinical outcomes and survival in patients undergoing bedside pleurodesis
212

Leucoplasia verrucosa proliferativa X leucoplasias oral: um estudo clínico comparativo e análise crítica dos critérios de diagnóstico / Proliferative verrucous leukoplakia X oral leukoplakia: a comparative clinical study and a critical analysis of diagnostic criteria

Viviana Lanel 14 December 2011 (has links)
A leucoplasia verrucosa proliferativa (LVP) é classificada como um subtipo da leucoplasia oral (LO), de rara incidência e alto potencial de malignização. Acomete com maior frequência pacientes do gênero feminino, acima da sétima década de vida e apresenta altos índices de recorrência após a realização de qualquer modalidade de tratamento. Seu aspecto clínico inicial é caracterizado pela presença de lesão branca, homogênea, aparentemente inócua, que desenvolve áreas eritematosas, superfície verrucosa, comportamento agressivo e envolvimento multifocal com o passar do tempo. A evolução clínica é geralmente lenta, levando anos para que ocorra transformação maligna. Existem divergências na literatura quanto aos critérios utilizados em seu diagnóstico. Alguns autores preconizam aqueles descritos em seu primeiro relato em 1985, que exigiam o acompanhamento das lesões desde sua fase inicial até o desenvolvimento de áreas verrucosas enquanto outros acreditam que o aguardo de fases avançadas apenas atrasa o diagnóstico e a instituição de tratamentos, aumentando as chances de malignização e piora do prognóstico dos pacientes. O objetivo desse estudo foi avaliar as características clínicas e demográficas dos indivíduos diagnosticados com LVP e compará-las a de pacientes diagnosticados com LO. Também foi realizada uma revisão e discussão dos critérios diagnósticos encontrados na literatura. Em nosso estudo analisamos retrospectivamente prontuários de pacientes diagnosticados na Disciplina de Estomatologia da FOUSP. Foram encontrados 9 pacientes diagnosticados com LVP, no período de 2007 a 2011, e 29 com LO, entre 1997 e 2011. Observamos que a LVP apresentou maior incidência em pacientes do gênero feminino, sem hábitos de tabagismo ou etilismo, com idade média de 73 anos. Já dentre os indivíduos com LO não encontramos diferença entre o envolvimento dos gêneros feminino e masculino, a idade média foi 57 anos e a maioria era tabagista ou etilista. O tempo médio de evolução da LVP foi de 5,4 anos enquanto da LO foi de 19,6 meses. Clinicamente, nenhum dos pacientes com LVP apresentou lesão homogênea inicial, sendo que todas eram multifocais, de comportamento agressivo e disseminado, com aspecto que variava desde placas brancas lisas até as nãohomogêneas, de superfície verrucosa, papilífera, com áreas eritematosas. Os pacientes com LO apresentavam lesões uni e multifocais localizadas, sendo que a maioria possuía placas brancas, de aspecto homogêneo. O grupo da LVP demonstrou taxas mais altas de recidiva em comparação as LO. A exigência de se acompanhar a lesão desde sua fase inicial e desconsiderar aquelas que apresentam aspecto multifocal na primeira consulta pode levar ao diagnóstico errôneo de uma verdadeira LVP, assim como aguardar o desenvolvimento de áreas verrucosas pode causar atraso considerável no diagnóstico, levando a tratamentos tardios e piorando o prognóstico do paciente. Sugerimos que dentre os critérios de diagnóstico da LVP devam ser considerados a presença de lesões brancas multifocais, lesões de comportamento agressivo, longo período de evolução, recorrência após qualquer forma de tratamento e não necessariamente apresentem aspecto verrucoso no momento do diagnóstico. / The proliferative verrucous leukoplakia (PVL) is a rare entity and was classified as a subtype of oral leukoplakia (OL). It affects more commonly elderly females and tends to recur after any type of treatment. Initially, it presents inconspicuous white lesions that progress to non-homogenous areas and develop verrucous surface, aggressive behavior and multifocal involvement over time. The lesions show a high tendency to transform into squamous cell carcinomas, usually taking years or decades to develop malignancy. There are controversies in the literature regarding the diagnostic criteria for PVL. Some authors follow those proposed on the first PVL report in 1985 which claimed continued follow-up since initial stages until the development of verrucous areas. Others believe that waiting for later stages postpone the diagnosis, worsening the patient´s prognosis. The objective of this study was to evaluate clinical and demographic aspects of patients with PVL and to compare them to patients diagnosed with OL. The diagnostic criteria reported on the literature were also revised. A retrospective study was performed and we analyzed patient´s records of Stomatology Department at FOUSP. Nine files of patients with PVL, diagnosed between 2007 and 2011 and 29 files of individuals with OL between 1997 and 2011 were studied. PVL showed higher incidence among women with no smoking or drinking habits with an average age of 73 years old while OL affected smoking and drinking patients, with a median age of 57 years old, with no gender predilection. PLV lesions progressed over a 5.4-year period while OL lesions took 19.3 months. Clinically, none of the PVL patients presented unifocal homogenous white lesion at the time of diagnosis. All of them showed aggressive and multifocal lesions, varying from homogenous to non homogenous aspect with verrucous surface and erythematous areas. OL individuals showed uni or multifocal white lesions with more restricted behavior. PVL group presented higher recurrence rate when compared to OL group. It is believed that not taking into account patients with multifocal lesions on the first visit can misdiagnose real PVL cases and waiting for the development of verrucous areas postpones the diagnosis and worsens the prognosis. It is suggested that PVL diagnostic criteria should include the presence of multifocal white lesions with aggressive behavior, long-term evolution, recurrences after any type of treatment and excludes the obligation of verrucous aspect on the time of diagnosis.
213

Avaliação de moléculas envolvidas no escape imunológico em desordens potencialmente malignas de boca / Evaluation of molecules involved in immunological escape in potentially malignant disorders of mouth

Gonçalves, Andréia de Souza 20 February 2017 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-03-16T17:16:39Z No. of bitstreams: 2 Tese - Andréia de Souza Gonçalves - 2017.pdf: 2952330 bytes, checksum: 1e8c4975cba85c509fcbc41ceea34245 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T13:18:44Z (GMT) No. of bitstreams: 2 Tese - Andréia de Souza Gonçalves - 2017.pdf: 2952330 bytes, checksum: 1e8c4975cba85c509fcbc41ceea34245 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T13:18:44Z (GMT). No. of bitstreams: 2 Tese - Andréia de Souza Gonçalves - 2017.pdf: 2952330 bytes, checksum: 1e8c4975cba85c509fcbc41ceea34245 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Study Rationale: Oral potentially malignant disorders (OPMDs) consist of morphologically altered tissues, which present a greater risk of malignant transformation than normal tissue. The most frequently found OPMDs are leukoplakia (OL) and actinic cheilitis (AC). It is now known that mutated or genetically altered cells have developed immunomodulatory strategies which allow them to escape antitumor immune response. The immune escape mechanisms used by mutated cells include the expressions of HLA-G, HLA-E and PD-L1 molecules and the IL-10 and TGF-β cytokines. Objective: To evaluate tissue and salivary expressions of HLA-G, HLA-E and PD-L1 molecules and IL-10 and TGF-β1, -β2 e -β3 cytokines in OPMDs, and relate such immunomodulatory mediators with antitumor immune response and potential for malignant transformation of lesions. Methods: Samples of patients with OL (n= 80) were submitted to immunohistochemistry and ELISA techniques to evaluate tissue and salivary expressions of the HLA-G, HLA-E, PD-L1, IL-10, TGF-β1, TGF-β2 and TGF-β3. In addition, samples of patients with QA (n= 30) were submitted to immunohistochemistry technique to evaluation tissue expression of HLA-G, HLA-E, PD-L1 and IL-10. Control group (n= 20) consisted of saliva and tissue of healthy individuals. The immunostained tissue samples were measured using a semi-quantitative method in association with staining intensity. The expression of these molecules and cytokines were related with the malignant potential of the lesions (epithelial dysplasia grading, proliferation- Ki-67 and apoptosis index- mutated p53). Moreover, the association with the density of granzyme B (GB+) cells and regulatory T cells FOXP3+ was investigated. The statistical tests used were: Fisher’s exact or Pearson Chi-Squared, Mann-Whitney and Kruskal- Wallis tests. The significance level was set at P < 0.05. Results: Fifteen samples showed severe dysplasia, twenty moderate, thirty-two mild and thirteen non-dysplasia. Forty samples (50%) of OL presented combined high Ki-67/p53. Irrespective of the severity of epithelial dysplasia and proliferation/apoptosis index in OL, an overexpression of HLA-G, -E, PD-L1, IL-10, TGF-β2 and -β3 was found in OL when compared with control (P < 0.05). The number of GB+ and FOXP3+ cells in OL was similar to control. Salivary concentration of sHLA-G, IL-10 and TGF-β did not allow distinction between OL patients and healthy individuals (P > 0.05). As regards to AC, we showed that this lesion had an increase in expression of HLA-G, HLA-E, IL-10 and PD-L1 when compared to control; however this increase was statistically significant only for PD-L1 (P= 0.04). Conclusion: The OL showed a reduced cytotoxic immune response (low number of GB+ cells) associated with a high expression of immunomodulatory mediators; however, this expression was independent of epithelial dysplasia grading, proliferation and apoptosis index. Regarding AC we also showed an increase in expression of HLA-G, -E, IL-10 and PD-L1 when compared to the control. Thus, our findings suggest that this lesion present an immunosuppressive microenvironment which favors the escape of mutated keratinocytes in any stage dysplastic, proliferation or apoptosis which this disease finds itself. / Justificativa do estudo: As desordens potencialmente malignas (DPMs) de boca consistem em tecidos morfologicamente alterados, os quais apresentam maior risco de transformação maligna que o tecido normal. Dentre as DPMs de boca, as mais frequentes são a leucoplasia (LE) e a queilite actínica (QA). Atualmente, sabe-se que células mutadas ou geneticamente alteradas são capazes de desenvolver estratégias imunomodulatórias que lhes permitem a evasão à resposta imune antitumoral. Dentre esses mecanismos, pode-se citar a expressão das moléculas HLA-G, HLA-E e PD-L1 e das citocinas IL-10 e TGF-β. Objetivo: Avaliar a expressão tecidual e salivar das moléculas HLA-G, HLA-E e PD-L1 e das citocinas IL-10 e TGF-β1, -β2 e -β3 em DPMs de boca e relacionar tais mediadores imunomodulatórios com a resposta imune antitumoral e com o potencial de transformação maligna dessas lesões. Metodologia: Amostras de pacientes acometidos pela LE (n= 80) foram submetidas às técnicas da imunoistoquímica e ELISA para avaliação da expressão tecidual e salivar, respectivamente, das proteínas supracitadas. Adicionalmente, amostras de pacientes acometidos pela QA (n= 30) foram submetidas à técnica da imunoistoquímica para avaliação da expressão tecidual das proteínas HLA-G, HLA-E, PD-L1 e IL-10. O grupo controle (n= 20) consistiu de tecido e saliva de indivíduos saudáveis. As amostras teciduais imunomarcadas foram mensuradas por um método semi-quantitativo associado à intensidade de marcação. A expressão dos mediadores imunomodulatórios foi associada com o potencial de malignização das lesões (gradação de displasia epitelial, índice de proliferação celular- Ki-67 e apoptose- p53 mutado). Além disso, a associação com a densidade de células granzima B+ (GB+) e células T regulatórias FOXP3+ foi investigada. Os testes estatísticos utilizados foram: teste exato de Fisher ou qui-quadrado de Pearson, Mann-Whitney e Kruskal- Wallis. O nível de significância foi estabelecido em P < 0,05. Resultados: No que se refere a LE, o presente estudo demonstrou que 15 amostras apresentaram displasia severa, 20 moderada, 32 leve e 13 sem displasia. Quarenta amostras (50%) apresentram o combinado alto Ki-67/p53. Independente da severidade da displasia epitelial e do índice de proliferação celular/ apoptose, observou-se uma expressão aumentada de HLA-G, HLA-E, PD-L1, IL-10, TGF-β2 e -β3 quando comporado ao controle (P < 0.05). O número de células GB+ e FOXP3+ nas LE foi similar ao controle. Os níveis salivares de HLA-G solúvel (HLA-Gs), IL-10 e TGF-β não nos possibilitou uma diferenciação entre os pacientes com LE e indivíduos saudáveis (P > 0,05). Em relação aos resultados obtidos para QA, evidenciou-se que essa lesão teve um aumento na expressão de HLA-G, HLA-E, IL-10 e PD-L1 em comparação ao controle, todavia esse aumento só foi estatisticamente significativo para o PD-L1 (P= 0,04). Conclusão: As LEs apresentaram uma reduzida resposta imunológica citotóxica (baixo número de células GB+) associada a uma elevada expressão de mediadores imunomodulatórios; todavia essa expressão não possui relação com a gradação de displasia epitelial e índice de proliferação celular e apoptose. Em relação à QA, nós também evidenciamos uma maior expressão de HLA-G, HLA-E, IL-10 e PD-L1 se comparado ao controle. Desta forma, nossos achados sugerem que tais lesões apresentam um microambiente imunossupressor que favorece a evasão de queratinócitos mutados em qualquer estágio de alteração displásica, proliferação ou apoptose que essa doença se encontre.
214

Clostridioses em ruminantes na região sul do Rio Grande do Sul / Clostridial diseases in ruminants in southern Rio Grande do Sul

Quevedo, Pedro de Souza 20 December 2010 (has links)
Made available in DSpace on 2014-08-20T14:38:01Z (GMT). No. of bitstreams: 1 dissertacao_pedro_quevedo.pdf: 852940 bytes, checksum: 646d10b8df90285825807c9a0da507ab (MD5) Previous issue date: 2010-12-20 / A retrospective study of clostridial diagnosed in ruminants from 1978-2008 in southern Rio Grande do Sul, was conducted in the influence area of the Regional Diagnostic Laboratory of the Federal University of Pelotas. Out of 5.446 bovine specimens sent by practitioners or from necropsies performed 91 (1,67%) were diagnosed as clostridiosis. Of those, 30 (0.55%) were diagnosed as by black leg, 15 (0.27%) as bacillary hemoglobinuria, 9 (0.16%) as botulism, 9 (0.16%) as malignant edema, and 28 (0.51%) as tetanus. Out of 860 sheep specimens 49 (5.69%) were bacterial diseases and 14 (28,57%) of those were diagnosed as clostridiosis, being 10 (1.16%) cases of tetanus, 3 (0.34%) of malignant edema, and 1 (0.11%) %) of enterotoxemia. It was concluded that some clostridiosis cause important losses in livestock in Rio Grande do Sul, mainly black leg. The vaccination of young stock against black leg is recommended in the whole state. Vaccination against botulism is recommended in areas of native pastures where phosphorus deficieny occurs, and vaccination against bacillary hemoglobinuria is recommended in low lands where fasciolosis is enzootic. In cattle, tetanus may occur as outbreaks with significant economic losses, recommending also the vaccination of animals. In sheep clostridioses are less important being tetanus the more frequent. Good hygienic practices, mainly during castration or tail are recommended to prevent the disease. Enterotoxemia is a rare disease in the region, because most sheep are raised in native pastures with limited grass production; vaccination is only recommended in sheep grazing in cultivate pastures or supplemented with concentrates. / Foi realizado um estudo retrospectivo dos diagnósticos de clostridioses ocorridos na região sul do Rio Grande do Sul correspondente a área de influência do Laboratório Regional de Diagnóstico da Faculdade de Veterinária da Universidade Federal de Pelotas entre janeiro 1978 e janeiro de 2008 e acompanhados os casos de clostridioses diagnosticados nos anos 2009 e 2010. De um total de 5.446 materiais de bovinos provenientes de necropsias ou órgãos enviados 91 (1,67%) correspondiam a enfermidades causadas por bactérias do gênero Clostridium sendo 30 (0,55%) de carbúnculo sintomático, 15 (0,27%) de hemoglobinúria bacilar, 9 (0,16%) de botulismo, 9 (0,16%) de edema maligno e 28 (0,51%) de tétano. De 860 materiais de ovinos 49 (5,69%) diagnósticos corresponderam a doenças bacterianas e desses 14 (28,57%) foram de surtos de clostridioses. Dos 14 surtos de clostridioses observados em ovinos 10 (1,16%) foram de tétano, três (0,34%) de edema maligno e um (0,11%) de enterotoxemia. Concluiu-se que algumas clostridioses causam prejuízos econômicos à bovinocultura da região, principalmente o carbúnculo sintomático, recomendando-se a vacinação sistemática dos bovinos jovens contra esta clostridiose. Recomenda-se, também, a vacinação contra botulismo, em áreas de campo nativo onde ocorre carência de fósforo e contra hemoglobinúria bacilar em áreas de campos baixos onde ocorre infecção por Fasciola hepatica. Em bovinos o tétano pode ocorrer como surtos com prejuízos econômicos importantes, recomendando-se, também, a vacinação dos animais. Em ovinos as clostridioses têm pouca importância, sendo o tétano a mais frequente. Para a profilaxia desta doença em ovinos recomenda-se utilizar práticas de manejo, como descola e castração, em condições adequadas de higiene. Enterotoxemia é uma enfermidade rara na região por que a maioria dos ovinos permanece em campos nativos com limitada produção de foragem; recomenda-se a vacinação somente em animais em pastagens cultivadas ou suplementados com concentrados.
215

Studies on Photocytotoxic Iron(III) and Cobalt(III) Complexes Showing Structure-Activity Relationship

Saha, Sounik January 2010 (has links) (PDF)
Photodynamic therapy(PDT) has recently emerged as a promising new non-invasive treatment modality for a large number of neoplastic and non-neoplastic lesions. Photoexcitation of a photosensitizing drug in the tumor tissue causes generation of reactive oxygen species which results in cell death. The current porphyrinic photosensitizers suffer a wide range of drawbacks leading to the development of the chemistry of alternative photosensitizing agents in PDT. Among them, the 4d and 5d transition metal-based photosensitizers have been explored extensively with the exception of the 3d metal complexes. The objective of this thesis work is to design and synthesize photoactive iron(III) abd cobalt(III) complexes and evalutate their photonuclease and photocytotoxic potential. Bioessential 3d metal ions provide an excellent platform for metal-based PDT drug designing as because of its varied spectral, magnetic and redox properties, with its complexes possessing rich photochemical behavior in aqueous and non-aqueous media. We have synthesized binary iron(III) complexes as netropsin mimics using amino acid Schiff bases derived from salicylaldehyde/napthaldehyde and arginine/lysine. The complexes were found to be good AT selective DNA binders and exhibited significant DNA photocleavage activity. To enhance the photodynamic potential, we further synthesized iron(III) complexes of phenolate-based ligand and planar phenanthroline bases. The DNA photocleavage activity of these complexes and their photocytotoxic potential in cancer models were studied. ROS generated by these complexes were found to induce apoptotic cell death. Ternary cobalt(III) complexes were synthesized to study the effect of the central metal atom. The diamagnetic cobalt(III) complexes were structurally dissimilar to their iron(III) analogues. Although the Co(III)/Co(II) redox couple is chemically and photochemically accessible but the Co(III)-dppz complex, unlike its iron(III)-dppz analogue, exhibited selective damage to hTSHR expressing cells but not in HeLa cells. A structure-activity relationship study on iron(III) phenolates having modified dppz ligands was carried out and it was found that electron donating group on the phenazine unit and an increase of the aromatic surface area largely improved the PDT efficiency. Finally, SMVT targeted iron(III) complexes with biotin as targeting moiety were synthesized and the in vitro efficacy of the complexes was tested in HepG2 cells over-expressing SMVTs and compared to HeLa amd HEK293 cells. The complexes exhibited higher phytocytotoxicity in HepG2 than in HeLa and cells and HEK293 cells. An endocytotic mode of uptake took place in HepG2 cells whereas in HEK293 cells, uptake is purely by diffusion. This is expected to reduce the side-effects and have less effect on cells with relatively less SMVTs. In summary, the present research work opens up novel strategies for the design and development of primarily iron-based photosensitizers for their potential applications in PDT with various targeting moieties.
216

Mécanismes de résistance à la chimiothérapie dans les gliomes de haut grade de l’enfant : implications des systèmes de réparation de l’ADN et de l’hypoxie intra-tumorale / Mechanisms of chemo-resistance in pediatric malignant gliomas : involvement of DNA repair system and intra-tumor hypoxia

Nguyen, Aurélia 22 September 2014 (has links)
Les gliomes malins de l’enfant (GME), de pronostic sombre, se distinguent des gliomes malins de l’adulte (GMA) sur le plan biologique mais aussi clinique, avec des taux de réponse au témozolomide (chimiothérapie alkylante de référence chez l’adulte) moindres. L’efficacité du temozolomide est réduite par l’action de l’enzyme de réparation de l’ADN, l’O6-methylguanine-DNA-methyltransferase (MGMT), dont l’expression est fréquemment inhibée par méthylation du promoteur de son gène dans les GMA. En première partie, la mise au point d’une nouvelle technique de PCR spécifique de méthylation a montré une fréquence plus faible dans les GME (15%) vs les GMA (45%, p<0,001). En deuxième partie, l’hypoxie intra-tumorale et la dérégulation en amont de l’axe mTOR-HIF-1α, connus pour être impliqués dans la chimio-résistance, ont été étudiés dans les GME et ciblés par l’association rapamycin-irinotecan dans une étude in vitro, pour laquelle des lignées dérivées de GME ont été développées. / Pediatric malignant glioma (PMGs), are associated with a very dismal prognosis. They are distinct from their adult counterparts (AMGs), biologically but also clinically, with a lower response to temozolomide (the current reference alkylating chemotherapy) compared to AMGs. Temozolomide efficacy is reduced by the activity of the DNA repair enzyme, O6-methylguanine-DNA-methyltransferase (MGMT), whose expression is frequently silenced by promoter methylation. First, the development of a new methylation-specific PCR showed a lower frequency of MGMT methylation in PMGs (15%) vs AMGs (45%, p<0,001). Secondly, intra-tumor hypoxia and the upstream deregulation of mTOR-HIF-1α axis, well-known to be involved in chemo-resistance and the up-regulation of MGMT expression, were studied in a PMG cohort. The targeting of this axis was then studied in vitro using a therapy combining rapamycin and irinotecan. For this, pediatric patient-derived malignant glioma cell lines were developed.
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Head and Neck Cancer : Factors Affecting Tumour Growth

Sundelin, Kaarina January 2007 (has links)
Head and neck cancer is the fifth most common cancer worldwide with an estimated annual global incidence of over 500 000 cases. These malignant tumours develop in the mucosal linings of the upper respiratory tract or in the salivary glands. The most common sites are in the oral cavity and larynx. Treatment modalities comprising surgery and chemoradiotherapy have improved significantly during the last 20 years, but not the long-term survival of patients. The aim of this thesis was to study the different factors affecting tumour growth in head and neck cancer that may have clinical implications in the future. Factors involving apoptosis, cell cycle activity, inflammation, and enzyme activity were of special interest. The results of the thesis indicate that patients with malignant salivary gland tumours having the lowest level of actively replicating cells have the best prognosis. The largest amount of replicating cells in tongue cancer specimens was found in the peripheral areas of tumour nests. Metallothionein, a protein that can hinder apoptosis, was found in excess in the same areas, whereas apoptosis activity was considerably lower. Taken together, these results indicate that the most aggressive cancer cells are found in the peripheral areas of tumours where apoptosis may be hindered. The expression of the death receptor Fas was higher in tongue cancer specimens than in normal mucosa. The expression of this receptor was studied further in two cell lines established from oral cancers. When a low dose of cisplatin was added to cell cultures, the Fas expression was enhanced in both cell lines and, furthermore, the Fas-induced apoptosis was increased in one of the cell lines. The results show that a common chemotherapeutic drug given in a low, less toxic dose may enhance receptor-mediated apoptosis of cancer cells. Malignant solid tumours are often distinguished by an increased proteolytic activity resulting in invasive growth, neo-angiogenesis, and metastases. This activity is conducted by enzymes that are secreted from tumour cells, or from normal cells in the tumour microenvironment. The regulation of enzyme secretion may be mediated by cytokines, small signalling molecules also present in cancer tissue. The results of this thesis show that two cytokines can synergistically induce enzyme secretion (matrix metalloproteinase-1 and -9) from oral cancer cells. Cytokine tumour necrosis factor-alpha and hepatocyte growth factor added alone to cell cultures strongly stimulated secretion of these enzymes. Thus, the tested cytokines, which are commonly secreted by fibroblasts and immune cells, may promote tumour growth. This thesis has contributed to an increased understanding of factors affecting tumour growth in head and neck cancer. The upcoming cancer therapies will be based on the increasing knowledge of these and other aberrant cellular mechanisms that may vary between different cancer forms.
218

Přínosy preventivních programů novotvarů v České republice / Benefits of Preventive Programs of Malignant Cancer in the Czech Republic

Matějková, Karolína January 2017 (has links)
Due to the constantly increasing epidemiological burden of our population on oncological diseases, nationwide preventive programs for selected types of malignant tumors have been introduced within the Czech health system. The aim of this thesis is to analyze and evaluate these screenings, such as mammographic screening, cervical screening and screening of the colon and rectum. The subject of the analysis is the mortality rates for breast cancer (C50), cervix (C53) and colon and rectum cancer (C18-21) between 1994 and 2015. The main focus is on question of whether the development of the mortality rate for selected neoplasms depends on the degree of coverage rate by a preventive program.
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Perturbations de l'efflux calcique du réticulum dans la fibre musculaire squelettique de mammifère par l'expression de récepteurs de la ryanodine pathologiques et par certains phophoinositides / Alterations of sarcoplasmic reticulum calcium release by expression of pathological mutant ryanodine receptors and by phophoinositides in mammalian skeletal muscle fibers

Lefebvre, Romain 10 September 2012 (has links)
Les ions Ca2+ responsables de la contraction musculaire sont extrudés du réticulum sarcoplasmique (RS) via le récepteur de la ryanodine de type 1 (RyR1). Des mutations du gène de RyR1 sont responsables chez l’homme de l’hyperthermie maligne (HM) et de la myopathie à cores centraux (MCC). Nous avons caractérisé les altérations de l’efflux calcique du RS dues à de telles mutations dans la fibre musculaire de souris par électrophysiologie et imagerie confocale. L’expression des formes Y523S, R615C et R2163H de RyR1, associées à l’HM, provoque une hypersensibilité de l’efflux vis-à-vis du potentiel membranaire alors que les formes I4897T et G4896V associées à la MCC provoquent une réduction chronique de l’efflux sans modification de densité des RyR1 s ainsi que des protéines Cav1.1 et SERCA1. L’expression de la forme R4892W associée à la MCC ne modifie pas l’efflux calcique suggérant une plus faible pénétrance fonctionnelle de cette forme. Dans tous les cas, aucune indication de changement du contenu en calcium RS n’a été observée. Les résultats suggèrent que les modifications pathologiques de l’efflux calcique sont la conséquence directe de l’altération de fonction des canaux. Le deuxième objectif du travail s’est intéressé au rôle de certains phosphoinositides (PtdInsPs) dans la régulation de l’efflux calcique du RS. La surexpression de la PtdInsPs-phosphatase Mtm 1 n’a aucun effet sur l’efflux calcique alors que l’application intracellulaire de ses deux principaux substrats inhibe l’efflux, suggérant que leur accumulation dans les fibres musculaires déficientes en Mtm1 pourrait contribuer aux altérations pathologiques associées du couplage excitation-contraction / Ca2+ ions that trigger muscle contraction are released from the sarcoplasmic reticulum (SR) through the type 1 ryanodine receptor (RyR1) channel. Mutations of the gene encoding RyR1 are responsible for malignant hyperthermia (MH) and central core disease (CCD) in human. We characterized the alterations of SR Ca2+ release due to such mutations in mouse fibers using electrophysiology and confocal imaging. Expression of each of the MH-associated Y523S, R615C and R2163H mutant forms of RyR1 increases the sensitivity of Ca2+ release to membrane potential whereas forms I4897T and G4896V that are associated to CCD provoke a chronic depression of Ca2+ release with no concurrent alteration of RyR1, Cav1.1 and SERCA1 density. Expression of the CDD-associated R4892W form of RyR1 has no effect on Ca2+ release suggesting a weaker functional penetrance of this mutant form. In all cases we found no indication for a change in SR calcium content. Results suggest that pathological changes in Ca2+ release are the direct consequence of the functional alteration of the channels. The second goal of this work focused on the role of certain phosphoinositides (PtdInsPs) in the control of SR Ca2+ release. Over-expression of the PtdInsPs-phosphatase Mtm 1 does not affect Ca2+ release whereas intracellular application of its two main substrates inhibits Ca2+ release, suggesting that accumulation of these molecules in Mtm 1-deficient fibers could contribute to the associated alterations of excitation-contraction coupling
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Psoas abscess secondary to retroperitoneal distant metastases from squamous cell carcinoma of the cervix with thrombosis of the inferior vena cava and duodenal infiltration treated by Whipple procedure: a case report and review of the literature

Mehdorn, Matthias, Petersen, Tim-Ole, Bartels, Michael, Jansen-Winkeln, Boris, Kassahun, Woubet Tefera January 2016 (has links)
Background: Psoas abscess is a rare clinical disease of various origins. Most common causes include hematogenous spread of bacteria from a different primary source, spondylodiscitis or perforated intestinal organs. But rarely some abscesses are related to malignant metastatic disease. Case presentation: In this case report we present the case of a patient with known squamous cell carcinoma of the cervix treated with radio-chemotherapy three years prior. She now presented with a psoas abscess and subsequent complete inferior vena cava thrombosis, as well as duodenal and vertebral infiltration. The abscess was drained over a prolonged period of time and later was found to be a complication caused by metastases of the cervical carcinoma. Due to the massive extent of the metastases a Whipple procedure was performed to successfully control the local progress of the metastasis. Conclusion: As psoas abscess is an unspecific disease which presents with non-specific symptoms adequate therapy may be delayed due to lack of early diagnostic results. This case report highlights the difficulties of managing a malignant abscess and demonstrates some diagnostic pitfalls that might be encountered. It stresses the necessity of adequate diagnostics to initiate successful therapy. Reports on psoas abscesses that are related to cervix carcinoma are scarce, probably due to the rarity of this event, and are limited to very few case reports. We are the first to report a case in which an extensive and complex abdominal procedure was needed for local control to improve quality of life.

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