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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.
131

Developing otitis media : experimental studies in particular regarding inflammatory changes in the tympanic membrane

Eriksson, Per Olof January 2004 (has links)
Otitis media (OM), one of the commonest of childhood diseases, causes much suffering. OM exists in a variety of forms, two of which are acute otitis media (AOM) and otitis media with effusion (OME). The clinical courses of these conditions differ, AOM usually presenting with earache, fever and/or aural discharge, and the OME usually with hearing impairment. The tympanic membrane (TM) mirrors the events in the middle ear cavity, and pars flaccida (PF) is the initial site of inflammatory changes in the TM. PF is rich in mast cells (MCs), which by releasing various mediators, may trigger TM inflammation. The aims of the present studies were to investigate early inflammatory changes in the TM in rat models of OM; after mast cell degranulation, in response to AOM, and OME, after myringotomy in AOM and in normal ears. Furthermore, we developed a new rat AOM model, that excludes surgical trauma and resembles the natural route of infection in man. AOM and OME elicited the first inflammatory response in PF of the TM. The response to OME was discrete, but a slight increase in macrophages was found. During the first 48 hours of AOM, the inflammatory response was intense, following a bimodal pattern. This reaction is similar to that found after MC degranulation. In AOM, macrophages were the predominant cell in PF, while in pars tensa (PT), polymorphonuclear cells (mainly neutrophils) predominated. When myringotomy was performed in AOM ears, the healing time was shorter than that of myringotomy in normal ears. The highly inflamed lamina propria seemed to promote healing. During early AOM, as well as following myringotomy, fibrin extravasates into PF and PT. This fibrin deposition may be involved in regulating the inflammatory response. Repeated nasal challenge with the otitis media pathogen Streptococcus pneumoniae provoked AOM and concomitant TM stimulation reduced the number of AOM cases. This new rat AOM model has the advantage of avoiding trauma in the middle ear cavity, while eliciting an intense inflammatory response in the middle ear cavity (MEC).
132

Expressão das proteínas CD90 e HIF-1 alfa no microambiente tumoral do carcinoma espinocelular de boca / Protein expression of CD90 and HIFf-1 alpha in microenvironment tumor the squamous cell carcinoma

Ribeiro, Maisa 19 February 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-09T12:38:26Z No. of bitstreams: 2 Dissertação - Maisa Ribeiro - 2015.pdf: 1621645 bytes, checksum: 2b3a1e65f1e53b4a1264cf3febb2c630 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-09T12:41:15Z (GMT) No. of bitstreams: 2 Dissertação - Maisa Ribeiro - 2015.pdf: 1621645 bytes, checksum: 2b3a1e65f1e53b4a1264cf3febb2c630 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-09T12:41:15Z (GMT). No. of bitstreams: 2 Dissertação - Maisa Ribeiro - 2015.pdf: 1621645 bytes, checksum: 2b3a1e65f1e53b4a1264cf3febb2c630 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-19 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In the lesions carcinomatous, low oxygen tension plays a crucial step in the self-renewal, metastatic potential, and therapy resistance of cancers. To adapt to the hypoxic microenvironment, neoplastic cells activate hypoxia-induced factor-1 alpha (HIF-1 alpha), which may mediates invasion and metastasis. In addition, the human THY-1 (CD90) cell surface protein mediates cell adhesion expressed in stem cells, and seens to drive tumor development in some malignant tumors. The present study investigates HIF-1 alpha (n=98) and CD90 (n=97) expression in oral squamous cell carcinoma (OSCC) and metastatic lymph nodes (n=24), the intratumoral region and the invasive front, by immunohistochemistry. Furthermore, clinicopathological data revised from the medical records. In superficial OSCCs, most tumor cells overexpressed HIF-1 alpha, whereas was restricted in the intratumoral region in invasive conventional SCCs. Interestingly, metastatic lymph nodes (91.7%, p=0.001), and intratumoral regions of its corresponding primary tumors (83.3%, p<0.001) were invaded by HIF-1 alpha-positive neoplastic cells. Overall survival was poor in patients with nodal involvement. CD90 was expressed mostly in microvessels and granulocyte cells similar to mast cells. These cells expressed CD90 mostly in the peritumoral region of invasive SCC (p<0.001). Microvessels CD90 positive were higher in the intratumoral region (p=0.032). Interesting, mast cell and microvessels positively correlated in OSCC (p=0.006; r²=0.077). In conclusion, hypoxic environment may facilitate regional metastasis and serve as a potential diagnostic and prognostic marker in OSCC primary tumors. Microvessels CD90 positive seems to promote tumor growth except in BSCC. Mast cell may occur via CD90 for tumor progression. / Nas lesões carcinomatosas a baixa tensão de oxigênio desempenha um passo crucial para a auto-renovação, potencial metastático, e resistência à terapia no câncer. Para se adaptar ao ambiente hipóxico, células neoplásicas ativam o fator induzido por hipóxia-1 alfa (HIF-1 alfa), que pode facilitar a invasão e metástase. Além disso, o THY-1 (CD90) humano, uma proteína de superfície celular expressa em células estaminais, medeia a adesão celular, e parece promover o desenvolvimento em alguns tumores malignos. O presente estudo analisou a expressão das proteínas HIF-1 alfa (n = 98) e CD90 (n = 97) no carcinoma espinocelular de boca (CEC de boca) e linfonodos metastáticos (n=24), na região intratumoral e no fronte de invasão, por meio de imunoistoquímica. Além disso os dados clinicopatológicos foram revisados a partir dos prontuários médicos e a sobrevida foi analisada. No CEC microinvasivo, a maioria das células tumorais apresentaram superexpressão do HIF-1 alfa, enquanto que no CEC invasivo a superexpressão foi restrita na região intratumoral. Verificou-se que em linfonodos metastáticos (91,7%, p = 0,001), e regiões intratumorais dos seus tumores primários correspondentes (83,3%, p <0,001) houve forte expressão do HIF-1 alfa em células neoplásicas. A sobrevida global foi pior em pacientes com metástase regional. A proteína CD90 foi expressa principalmente em microvasos e células de granulócitos semelhantes aos mastócitos. Estas células expressaram CD90 principalmente na região fronte de invasão do CEC invasivo (p<0,001). A média de microvasos CD90 positivo foi maior na região intratumoral (p=0,032). Interessantemente, mastócitos e microvasos foram positivamente correlacionados no CEC de boca (p=0,006; r²=0,077). Em conclusão, o ambiente hipóxico pode facilitar metástases regionais e funcionar como um potencial marcador de diagnóstico e prognóstico em tumores primários do CEC de boca. Os microvasos CD90 positivo parecem promover o crescimento do tumor, exceto no carcinoma escamoso basalóide (CEB). Os mastócitos ativados via CD90 podem contribuir com a progressão do tumor.
133

Avaliação histoquímica e da expressão das proteínas p53 e c-KIT no mastocitoma canino

Pimenta, Vanessa de Sousa Cruz 25 April 2012 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-11-07T16:47:10Z No. of bitstreams: 2 Dissertalçao - Vanessa de Sousa Cruz Pimenta - 2012.pdf: 3213134 bytes, checksum: b135b98e005a73bd0b991b974142808b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-11-07T16:47:28Z (GMT) No. of bitstreams: 2 Dissertalçao - Vanessa de Sousa Cruz Pimenta - 2012.pdf: 3213134 bytes, checksum: b135b98e005a73bd0b991b974142808b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-07T16:47:28Z (GMT). No. of bitstreams: 2 Dissertalçao - Vanessa de Sousa Cruz Pimenta - 2012.pdf: 3213134 bytes, checksum: b135b98e005a73bd0b991b974142808b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-04-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to verify the pattern of staining by Bismarck Brown and evaluate the expression of p53 and c-KIT in neoplastic mast cells, quantifying the marking obtained by these antibodies using the Image J software and correlating the values found with histologic subtypes. Mast cell tumors are the most common skin neoplasms of dogs, is an excessive proliferation of neoplastic mast cells, of variable and unpredictable biological behavior, with great capacity of recurrences and metastasis. The lesions may be dermis or subcutaneous location and three grades are described. At the first, the tumor is well differentiated, moderately differentiated is the second and the third is little differentiated. Their cause is still unknown. One of the mechanisms proposed for the proliferation of mast cells is to change the nucleotide sequence of the c-KIT gene. The tumor suppressor gene TP53 is directly related to blockage of cell cycle and the protection is changed by mutations in the p53. Were reviewed 1242 protocols of histopathology exams obtained the archives of Laboratory of Animal Pathology/UFG, from January 2007 to April 2011, found 37 diagnosis of canine cutaneous mast cell tumor. Regarding the epidemiologic aspects the prevalence of 55.26% was noted in dogs in the age group 6-10 years, 63.16% female and 39.48% of the Boxer breed. The most common anatomic site was the hind-limb with 31.58% of records. Histologic evaluation and histochemistry using Hematoxylin - Eosin and Toluidine Blue allowed to classify the majority of mast cell tumors studied, although only 24.32% of the samples were identified using the color Bismarck Brown. The prevalence of Grade II was 43.24% of all cases The lowest value expressed for p53 and c-KIT, was in Grade II, the highest value in the Grade III and the highest average in grade I. Was concluded that the coloration of Bismarck Brown proved efficient to aid in the diagnostic accuracy of laboratory routine and utilization of antibodies anti p53 and anti c-kit promoted good immunostaining with important role to determine the prognosis of canine mast cell tumors. / O objetivo deste estudo foi verificar o padrão de coloração pelo Pardo de Bismarck e avaliar a expressão de p53 e c-KIT nos mastócitos neoplásicos, quantificando a marcação obtida por estes anticorpos através do software Image J e correlacionando os valores encontrados com os subtipos histológicos. O mastocitoma é a neoplasia cutânea mais frequente do cão, sendo uma proliferação excessiva de mastócitos neoplásicos, de comportamento biológico variável e imprevisível, com grande capacidade de recidivas e metástases. As lesões podem ser de localização dérmica a subcutânea e três graus são descritos. No primeiro, o tumor é bem diferenciado, no segundo é moderadamente diferenciado e no terceiro é pouco diferenciado. Sua causa ainda é desconhecida. Um dos mecanismos propostos para a proliferação de mastócitos é a alteração da sequência de nucleotídeos do gene c-KIT. O gene supressor de tumor TP53 está diretamente relacionado ao bloqueio do ciclo celular e a proteção é alterada por mutações da p53. Foram revisados 1242 protocolos de exames histopatológicos obtidos dos arquivos do Laboratório de Patologia Animal/UFG, do período de janeiro de 2007 a abril de 2011, encontrando 37 diagnósticos de mastocitoma cutâneo canino. Quanto aos aspectos epidemiológicos a prevalência notada foi de 55,26% de cães na faixa etária de 6-10 anos, 63,16% do gênero feminino e 39,48% da raça Boxer. A localização anatômica mais frequente foi o membro pélvico com 31,58% de registros. A avaliação histológica e histoquímica utilizando a Hematoxilina - Eosina e o Azul de Toluidina permitiu classificar a maioria dos mastocitomas estudados, porém 24,32% das amostras só foram identificadas com a utilização da coloração Pardo de Bismarck. A prevalência do Grau II foi de 43,24% do total dos casos. O menor valor expresso, por p53 e c-KIT, foi no Grau II, o maior valor no Grau III e a maior média no grau I. Foi possível concluir que a coloração Pardo de Bismarck mostrou-se eficiente para auxiliar na precisão dos diagnósticos da rotina laboratorial e a utilização dos anticorpos anti p53 e anti c-KIT promoveu boa imunomarcação, com papel importante na determinação do prognóstico do mastocitoma canino.
134

Fatores prognósticos em mastocitoma canino: Correlação entre parâmetros clínicos, histológicos, marcadores de proliferação e análise termográfica / Prognostic factors in canine mast cell tumors: correlation between clinical and histological parameters, proliferation markers and thermographic analysis

Samanta Rios Melo 21 June 2013 (has links)
Os objetivos deste trabalho foram: Analisar prospectivamente a eficácia da correlação entre parâmetros clínicos, histológicos, e marcadores de proliferação celular buscando melhores indicadores de prognóstico em casos de mastocitoma canino; Testar o uso de nova ferramenta diagnóstica e prognóstica para mastocitomas caninos: a termografia. Para isso, um total de 20 cães com diagnóstico citológico e histopatológico de mastocitoma tiveram suas formações excisadas e foram utilizados para estudo clínico e imunohistoquímico e dentre estes, 15 também para estudo termográfico. As avaliações imunohistoquímicas incluíram quantificação de AgNORs, PCNA, VEGF, localização de KIT. Os estudos termográficos incluíram análise e correlação das temperaturas no ponto central da formação (SpT), e na área da formação (AT) e em ponto de pele sadia (SpNT) e área equivalente, em pele sadia (ANT). Estatisticamente pode-se demonstrar uma correlação positiva significativa entre a classificação proposta determinada pela presença dos fatores prognósticos e o estadiamento proposto pela WHO. Não foi observada correlação estatística entre tempo livre de doença (óbito, novas formações, recidiva ou metástase) e o estadiamento ou fatores prognósticos. 95% (19/20) dos cães teve suas formações classificadas como Grau II e 5% (1/20) Grau I, segundo a classificação histológica de Patnaik (1984). Todos os cães tiveram suas formações classificadas como Baixo Grau, de acordo com a classificação proposta por Kiupell (2011). 5,6% (1/18) dos animais foi considerada padrão KIT - I, 44,4% (8/18) padrão KIT - II e 50% (9/18) padrão KIT - III. Não foi observada correlação estatística entre o padrão KIT e tempo livre de doença ou graduação histológica. Apesar de não significativo estatisticamente, foi notado menor tempo de sobrevida livre de doença nos animais com PCNA e AgNOR acima das medianas (p =0,089 e p = 0,080, respectivamente).O VEGF foi o único marcador a demonstrar relação significativa com o tempo livre de doença (p = 0,004). As análises termográficas indicaram média de temperatura do SpT de 33,18ºC, média de temperatura do SpNT de 33,39ºC, temperatura média de AT de 33,27ºC e temperatura média de ANT de 33,95ºC. A diferença entre os pontos mensurados foi em média -0,21ºC (variando entre -5,60ºC e +4,4ºC). A diferença entre os pontos mensurados foi em média -0,21ºC (variando entre -5,60ºC e +4,4ºC). Esta diferença foi negativa em 7/15 casos (47%) formações mais frias que a pele distante; e positiva em 8/15 casos (53%) formações mais quentes que a pele distante. Não foi possível correlacionar estatisticamente essas alterações de temperatura com a presença dos marcadores estudados, mas as análises estatísticas demonstram que a termografia na região tumoral é estatisticamente diferente da região não tumoral. / The objectives of this study were: To prospectively analyze the effectiveness of the correlation between clinical, histologic, and cell proliferation markers, seeking better indicators of prognosis in cases of canine mast cell tumor; and testing the use of new diagnostic and prognostic tool for canine mast cell tumor: thermography (infrared images); A total of 20 dogs with histopathological and cytological diagnosis of mast cell tumor were excised and their formations were used for immunohistochemical and clinical study, and 15 of those were also used for thermographic study. The evaluations included immunohistochemical quantification of AgNOR, PCNA, VEGF, KIT location. The studies included thermographic images analysis and correlation of the temperatures at the midpoint of tumor (SPT), and tumor area (AT) and point of healthy skin (SpNT) and equivalent area in healthy skin (ANT). We were able to demonstrate a statistically significant positive correlation between the proposed classification determined by the presence of prognostic factors and staging proposed by the WHO. No correlation was found between disease-free interval (death, new formations, recurrence or metastasis) staging, and prognostic factors. 95% (19/20) of the dogs had their tumors classified as Grade II and 5% (1/20) as Grade I, according to the histological classification of Patnaik (1984). All dogs had their tumors classified as low-grade, according to the classification proposed by Kiupell (2011). 5.6% (10/18) of the animals was graduated as KIT - I, 44.4% (8/18) as KIT - II and 50% (9/18) as KIT - III. No correlation was found between the KIT pattern and disease-free interval or histological grade. Although not statistically significant, we observed a shorter disease-free survival in animals with PCNA and AgNOR above the median (p = 0.089 and p = 0.080, respectively). VEGF was the only marker to show a significant relationship with disease-free interval (p = 0.004). The thermographic images analysis indicated average temperature on SpN of 33.18 º C, SpNT average temperature of 33.39 ° C, AT average temperature of 33.27 º C and ANT average temperature of 33.95 ° C. The difference between the measured points averaged -0.21 ° C (ranging between -5.60 ° C and +4.4 ° C). The difference between the measured points averaged -0.21 ° C (ranging between -5.60 ° C and + 4.4 ° C). This difference was negative in 7/15 cases (47%) - formations cooler than the healthy skin, and positive in 8/15 cases (53%) - formations warmer than the healthy skin. We could not statistically correlate these changes in temperature in the presence of the markers studied, but the statistical analyzes demonstrated that in the region thermography tumor is statistically different from non-tumor region.
135

Comparação da eficácia do mesilato de imatinibe com a vimblastina associada a prednisona no tratamento do mastocitoma canino: estudo clínico, histopatológico, imunohistoquímico e molecular / Comparison of the efficacy of imatinib mesylate with vinblastine and prednisone in the treatment of canine mast cell tumor: clinical, histological, immunohistochemical and molecular study

Thais Rodrigues Macêdo 22 August 2014 (has links)
O objetivo deste trabalho foi avaliar a eficácia do mesilato de imatinibe, em comparação com a quimioterapia usual com vimblastina e prednisona, no tratamento do mastocitoma canino e descrever os efeitos colaterais apresentados pelas medicações. Bem como analisar a expressão do VEGF (fator de crescimento endotelial), a relação da expressão do gene c-kit por RT-PCR e marcação imunoistoquímica do KIT com a presença de mutações na justamembrana e a relação desta mutação com a resposta à terapia. Para tanto foram incluídos 29 animais com diagnóstico citológico de mastocitoma, estes animais foram submetidos a tomografia computadorizada para determinação das medidas das formações cutâneas e em seguida divididos em 2 grupos. O grupo 1 foi tratado com o protocolo quimioterápico de vimblastina e prednisona por 12 semanas e o grupo 2 com o mesilato de imatinibe na dose de 10 mg/Kg a cada 24 horas por 8 semanas. A avaliação da resposta ao tratamento foi realizada com mensurações periódicas das formações com paquímetro e nova tomografia ao final do tratamento para mensuração do maior diâmetro e volume tumoral. Um fragmento das formações cutâneas foi coletado antes do início do tratamento para graduação histológica da neoplasia, determinação do índice mitótico e imunomarcação para KIT, VEGF e Ki- 67. Parte do material coletado teve o DNA e RNA extraídos e posterior sequenciamento dos exons 11 do gene c-kit e determinação da expressão deste e do seu ligante por RT-PCR. A toxicidade a medicação foi avaliada segundo as normas do VCOG 1.1.A taxa de resposta do grupo VP foi de 7,7 % e no grupo MI de 28,6%, embora os pacientes tratados com mesilato de imatinibe tenham apresentado maior chance de resposta a terapia, não foi observado diferença entre os dois grupos. Os dois protocolos foram bem tolerados, os pacientes do grupo MI d menor número de efeitos colaterais. O grau histológico, Indice mitótico, padrão imunohistoquimico do KIT, além da quantificação do ki-67 foram homogêneos nos dois grupos e não influenciaram na resposta ao tratamento. A quantificação do VEGF foi mais intensa nos pacientes com remissão parcial e total. Não foi observado relação entre a quantificação do KIT e a expressão do gene c-kit, que foi maior nos pacientes que responderam ao tratamento, porém a associação desta com a resposta a terapia não pode ser determinada. Mutações ativantes no exon11 do gene c-kit não foram identificadas. O tratamento com o mesilato de imatinibe é bem tolerado pelos animais, no entanto este não se mostrou superior ao protocolo padrão de quimioterapia para o tratamento do mastocitoma; este resultado pode ter sido influenciado pelo número de animais incluídos no estudo. Mutações em outros domínios do receptor KIT e a ação do ITK em receptores como do PDGF e o VEGF podem estar relacionados a resposta a esta classe de fármacos observada neste estudo, a despeito da ausência de mutações ativantes no exon 11 do gene c-kit. / The objective of this study was to evaluate the efficacy of imatinib mesylate, compared with the usual chemotherapy with vinblastine and prednisone in the treatment of canine mast cell tumor and describe the side effects submitted by medications. Well as analyzing the expression of VEGF (vascular endothelial growth factor), the relationship between the expression of c-kit gene by RT-PCR and immunohistochemical staining of KIT with the presence of mutations in the juxtamembrane and the relationship of this mutation with response to therapy. For both 29 animals with cytological diagnosis of mast cell tumor were included, these animals underwent computed tomography to determine the measured skin formations and then divided into 2 groups. Group 1 was treated with the chemotherapeutic protocol vinblastine and prednisone for 12 weeks and the second group with the imatinib mesylate in a dose of 10 mg / kg every 24 hours for 8 weeks. The assessment of response to treatment was performed with periodic measurements of the formations Caliper and a new computed tomography in the end of treatment to measure the largest tumor diameter and volume. A fragment of skin formations was collected before the initiation of treatment for histological grading, determination of mitotic index, KIT and VEGF staining patterns and the proliferation marker Ki67. Part of the collected material was extracted RNA and DNA and subsequent sequencing of 11 exons of the c-kit gene and determination and expression of its ligand by RT-PCR. The medication toxicity was evaluated according to the standards of VCOG 1.1.A response rate of the VP group was 7.7% and 28.6% MI group, although patients treated with imatinib had a higher chance of response therapy, no difference in response between the two groups was observed. The two protocols were well tolerated, patients in the MI group had a smaller number of side effects. The histological grade, mitotic index, staining patterns KIT, beyond the quantification of Ki-67 were homogeneous in both groups and did not influence the response to treatment. Quantification of VEGF was intensely in patients with partial and total remission. It was no relationship between KIT and quantification of the expression of c-kit gene, which was higher in patients who responded to treatment, but its association with response to therapy cant be determined. Exon11 activating mutations in the c-kit gene were not identified. Treatment with imatinib mesylate is well tolerated by the animals, however this was not superior to standard chemotherapy protocol for the treatment of mast cell tumors; this result may have been influenced by the number of animals included in the study. Mutations in other domains of the KIT receptor and action in ITK receptors as PDGF and VEGF may be related to response to this class of drugs in this study, despite the absence of activating mutations in exon 11 of c-kit gene.
136

Estudo crítico de mastocitomas caninos e avaliação termográfica de técnicas de anaplastia / Critical study of canine mast cell tumors and thermographic evaluation of reconstructive surgery

Samanta Rios Melo 26 July 2017 (has links)
Em grande parte das vezes, a excisão cirúrgica apropriada de mastocitomas em cães requer a realização de técnicas de reconstrução para o fechamento da ferida resultante, e o seu conhecimento se torna essencial para todo o cirurgião. Alcançar margens livres tem uma influência significativa sobre o tempo de sobrevida, e deve ser o objetivo para a maioria dos pacientes. A avaliação da evolução de retalhos cutâneos e a mensuração da aderência e neovascularização do tecido no local intencionado é extremamente importante para diagnóstico precoce de falhas na implantação do tecido. Não há evidências em literatura de trabalhos relacionados a avaliação da perfusão tecidual de retalhos cutâneos em animais de companhia, com o uso de técnicas de termografia. Neste trabalho, foram obtidas imagens, do tipo padrão e do tipo termográficas, de 63 mastocitomas, provenientes de 60 cães. A classificação histológica determinada neste estudo foi significativa na influência à sobrevida (p&lt;0,001). A pontuação prognóstica (0-13) aqui proposta, adaptada de Melo e colaboradores (2015) teve forte associação com sobrevida (p&lt;0,001). A presença de metástase foi observada em 17% dos casos, e de recidiva em 14%. Em ambas as ocorrências 90% dos animais acometidos vieram a óbito. Por meio de analises estatísticas comprovamos a associação entre esses dois fatores (metástase e recidiva) com o tempo de sobrevida (em ambas p&lt;0,001). Dentro do nosso estudo foi observado que, em tumores com a presença de AIM (agrupamentos independentes de mastócitos) há um risco de mortalidade 8,57 vezes maior do que animais com margens livres ou mesmo comprometidas. Esse risco é inclusive maior do que o risco de óbito em animais com recidiva (HR 5,13). VEGF-A se mostrou de significância estatística perante sobrevida; confirmando estudo anteriores e sugerido mais uma vez a inclusão desse marcador no perfil prognóstico do mastocitomas. Todas as formações apresentadas neste estudo tiveram análise termográfica concluída e documentada. Nota-se que mesmo quando considerado ponto central ou quando considerada toda área tumoral, 65 e 67% respectivamente, dos mastocitomas eram mais quentes que a pele sadia circundante. A causa destas mudanças de temperatura não é totalmente compreendida, mas sugere-se que esteja associada a neoangiogênese e inflamação local (XIE et al., 2004). Por meio das análises estatísticas é possível afirmar que as regiões tumoral e não tumoral são significativamente diferentes, tanto na avaliação de ponto central (SpT e SPNT) como na avaliação da área (AT e ANT) do tumor e pele circundante sadia (p &lt; 0,001). Ainda por meio de termografia, pudemos estabelecer que retalhos cutâneos pediculados apresentaram chance de deiscência 5,57 vezes maior do que o uso de outras técnicas de anaplastia e deslizamento de tecidos. Por fim, conseguimos estabelecer uma curva térmica de evolução das feridas da nossa população do estudo, bem como diferenciar o comportamento térmico quando há ou não deiscência. Isso pode ser útil a estudos futuros ou mesmo à prática clínico-cirúrgica, de modo a comparar a evolução de pacientes com as curvas previamente aqui estabelecidas, sendo factível assim prever a cicatrização da ferida. Acreditamos, por meio deste estudo, que a análise termográfica da evolução de retalhos cutâneos pode ser usada como correspondente a perfusão tecidual, conforme indicado em literatura e ser usada como ferramenta de reconhecimento precoces de deiscência da ferida cirúrgica, conforme proposto por diversos autores (SALMI et al., 1995; EICHHORN et al., 2009; WEERD et al., 2009; WEERD et al., 2011). / In most cases, proper surgical excision of mast cell tumors in dogs requires reconstructive techniques for the closure of the resulting wound, and it knowledge becomes essential for the surgeon. Achieving free margins has a significant influence on survival time, and should be the goal for most patients. The evaluation of the evolution of cutaneous flaps and the measurement of tissue adherence and vascularization at the intended site is extremely important for early diagnosis of defects in tissue implantation. There is no evidence in literature of studies related to evaluate tissue perfusion of skin flaps in companion animals, using thermography techniques. In this study, standard images and thermographic ones were obtained from 63 mast cell tumors from 60 dogs. The histological classification of the tumors in this study was significant in survival time (p &lt;0.001). The prognostic score (0-13) proposed here, adapted from Melo et al. (2015), had also strong association with survival time (p &lt;0.001). The presence of metastasis was observed in 17% of cases, and relapse in 14%. In both cases, 90% of the affected animals died. By means of statistical analyzes, we verified the association between these two factors (metastasis and relapse) in survival time (for both p &lt;0.001). Within our study it was observed that in tumors with the presence of AIM (independent mast cell groups) there is a mortality risk 8.57 times higher than animals with free or even compromised margins. This risk is even greater than the risk of death in animals with relapse (HR 5,13). Also, VEGF-A was shown to be statistically significant at survival time; confirming previous studys and leading us to suggets once again the inclusion of this marker in the prognostic profile of mast cell tumors. All the tumors presented in this study had a thermographic analysis completed and documented. It is noted that even when considered central point or tumor area, 65 and 67% respectively, of the mast cell tumors were warmer than the surrounding healthy tissue. The cause of these temperature changes is not fully understood, but it is suggested to be associated with neoangiogenesis and local inflammation (XIE et al., 2004). By means of the statistical analyzes it is possible to affirm that the tumoral and non-tumoral regions are significantly different, as well as in the evaluation of the central point (SpT and SPNT) and in the evaluation of the tumoral area (TA and ANT) im comparison with healthy surrounding skin (p &lt;0.001 ). Also through thermography, we could establish that skin flaps had a chance of dehiscence 5.57 times greater than the use of other techniques of reconstructive surgery. Finally, we were able to establish a thermal curve of evolution of the wounds of our study population, as well as to differentiate the thermal behavior when there is or not dehiscence. This may be useful for future studies or even clinical-surgical practice, in order to compare the evolution of patients with the curves previously established here, and it is feasible to predict wound healing. We believe, by means of this study, that the thermographic analysis of the evolution of cutaneous flaps can be used as corresponding to tissue perfusion, as indicated in the literature and be used as an early recognition tool for surgical wound dehiscence, as proposed by several authors (SALMI et al., 1995; EICHHORN et al., 2009; WEERD et al., 2009; WEERD et al., 2011).
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Regulační úlohy proteinů PAG a CSK v FcɛRI signalizaci žírných buněk / Regulatory roles of PAG and CSK in FcɛRI signaling of mast cells

Potůčková, Lucie January 2017 (has links)
8 1 ABSTRACT (EN) This thesis is focused mainly on understanding mechanisms of regulatory roles of C-terminal Src kinase (CSK) and phosphoprotein associated with glycosphingolipid- enriched microdomains (PAG) in the high-affinity IgE receptor (FcɛRI)-mediated signaling of murine mast cells. FcɛRI activation is initiated by aggregation of the receptor by complexes of multivalent antigen with IgE, followed by activation and enhanced activities of protein tyrosine kinases, phosphatases, adaptor proteins and number of other signal transduction molecules. The signaling events result in mast cell degranulation and release of variety of proinflammatory mediators, responsible for initiation of allergy and other inflammatory diseases. Understanding the function of key regulatory molecules controlling FcεRI-mediated mast cell activation, degranulation, and cytokines production could have therapeutic impact. CSK is a major negative regulator of Src family tyrosine kinases (SFKs) that play a critical role in various immunoreceptor signaling events. However, its function in mast cell activation has not been completely understood. Because of its cytoplasmic localization, CSK was assumed to be brought to the vicinity of the plasma membrane- bound SFKs via binding to membrane-bound adaptors and PAG was a major candidate....
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Mast Cell Regulation of Cardiovascular Inflammation I: Cognate and Non-Cognate Interactions

Negi, Smita, Halawa, Ahmad, Chi, David S., Miller, Christopher, Hossler, Fred E., Youngberg, George, Johnson, David A., Krishnaswamy, Guha 01 January 2010 (has links)
The paradigm shift in cardiovascular biology has been the understanding that atherosclerosis involves not just a mechanical deposition of lipids in the vessel wall, but a dynamic process involving the inflammatory response with cellular infiltration and inflammatory mediator expression. Typical cellular elements that have been studied include endothelial cells, vascular smooth muscle, T lymphocyte and the macrophage. Recent data suggests a role for the human mast cell. The human mast cell is a tissuedwelling cell, typically perivascular in distribution. This multifunctional cell responds rapidly to challenge with the release of inflammatory mediators that can orchestrate an immune response and may have relevance to atherogenesis. Mast cells have been shown to modulate various aspects of cardiovascular disease such as atherogenesis (endothelial activation, cytokine generation and foam cell formation) as well as rupture of an unstable atheromatous plaque. Mast cell activation in the context of cardiovascular disease may occurby cognate cell-cell interactions (interactions with macrophages, T cells, endothelial cells or smooth muscle) or by non-cognate means (such as lipoproteins and other proatherogenic components). More studies are required in order to better understand the molecular role of mast cells in vascular inflammatory disease.
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Mast cells mediate systemic immunosuppression induced by platelet-activating factor via histamine and cyclooxygenase-2 dependent mechanisms

Ocaña, Jesus Alejandro 02 May 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Platelet-activating Factor (PAF) stimulates various cell types by the activation of the G-protein coupled PAF-receptor (PAFR). Systemic PAFR activation induces an acute pro-inflammatory response, as well as delayed systemic immunosuppressive effects in vivo. De novo enzymatic PAF synthesis and degradation are closely regulated, but oxidative stressors, such as UVB, and cigarette smoke, can generate PAF-like species via the oxidation of membrane lipids in an unregulated process. Mast cells (MCs) and the PAFR have been shown to be necessary to mediate the resulting systemic immune suppression from oxidative stressors. The work herein implicates pro-oxidative chemotherapeutics, such as melphalan and etoposide, in mediating augmentation in tumor growth by inducing the generation of PAFR agonists via the oxidation of membrane lipids. This work also demonstrates the role of MCs and MC-released mediators in PAFR systemic immunosuppression. Through a contact hypersensitivity (CHS) model, the MC PAFR was found to be necessary and sufficient for PAF to mediate systemic immunosuppression. Additionally, activation of the MC PAFR seems to induce MC histamine and prostaglandin E2 release. Furthermore, by transplanting histamine- or COX-2-deficient MCs into MC-deficient mice, MC-derived histamine and prostaglandin release were found to be necessary for PAF to induce systemic immunosuppression. Lastly, we have evidence to suggest that prostaglandin release modulates MC migration to draining lymph nodes, a process necessary to promote immunosuppression. These studies fit with the hypothesis that MC PAFR activation mediates PAFR systemic immunosuppression in part by histamine and prostaglandin release.
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CCL2 (MCP-1) MEDIATES CHRONIC PELVIC PAIN THROUGH MAST CELLS IN EXPERIMENTAL AUTOIMMUNE CYSTITIS

Bicer, Fuat 28 August 2012 (has links)
No description available.

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