Navegando por Palavras-chave "Mesocricetus"
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- ItemSomente MetadadadosAnálise do comportamento de variantes fenotípicas de cepas de Mycobacterium avium em animais e macrófagos(Universidade Federal de São Paulo (UNIFESP), 2006) Oliveira, Rosangela Siqueira de [UNIFESP]; Leão, Sylvia Cardoso [UNIFESP]Mycobacterium avium é uma bactéria ambiental e na classificação de patogenicidade está incluída entre as micobactérias potencialmente patogênicas, pois se trata de um patógeno oportunista em animais e humanos. O interesse em estudar fatores de virulência e patogenicidade destas bactérias aumentou após o isolamento de M. avium em amostras de pacientes portadores do vírus da Imunodeficiência Humana (HIV). O objetivo deste estudo foi isolar variantes de colônias de sete cepas de M. avium isoladas de fontes humanas e animais, caracterizadas molecularmente em nosso laboratório e avaliar o comportamento e a capacidade de multiplicação das variantes fenotípicas em experimentos com animais (hamster) e cultura de células (macrófagos). Nos cultivos iniciais, cinco das sete cepas (71,4 por cento) apresentaram variantes de colônias OP e TL e duas cepas (28,6 por cento) não apresentaram variações no fenótipo das colônias. As colônias OP recuperadas dos baços dos animais inoculados mantiveram a mesma morfologia, branca opaca e lisa, enquanto que houve alteração na mortologia nas variantes TL, de lisa transparente para rugosa transparente (TL-Rg). As variantes mantiveram a mesma identificação original por PRA-hsp65 e a mesma tipificação por RFLP-IS1245 após a passagem por animais. Com todas as cepas houve maior recuperação de UFC por grama de baço e maior índice de multiplicação intracelular com a variante TL quando comparada à variante OP. Foi avaliado o percentual de células infectadas nos dias O e 7. Houve aumento no percentual de macrófagos infectados no dia 7 com todas as cepas, com diferença estatisticamente significante em 5 das 12 variantes das cepas estudadas. Quanto ao número de bacilos por macrófago infectado, foi observado que no dia O a maioria dos macrófagos infectados com as variantes OP e TL albergaram de 1 a 15 bacilos enquanto que no dia 7 a quantidade de bacilos que os macrófagos albergaram foi distribuída em freqüências de 1 a mais que 50. Com todas as cepas, a variante TL apresentou uma tendência de distribuição nas freqüências mais elevadas quando comparada à distribuição da variante OP no dia 7. A variante TL das cepas do estudo apresentou maior capacidade de sobrevivência e multiplicação em experimentos "in vivo" e "in vitro".
- ItemAcesso aberto (Open Access)Experimental model in hamster (Mesocricetus auratus) to study heterologous graft of scars and cutaneous diseases in plastic surgery(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2004-12-01) Hochman, Bernardo [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Bôas, Flaviane Cássia Vilas [UNIFESP]; Mariano, Mario [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); São Paulo University Biomedical Sciences Institute Immunology Department; Universidade de São Paulo (USP)Syrian golden hamster (Mesocricetus auratus) has in its cheek pouches sub-epithelium an Immunologically Privileged Site which allows the integration of homo- and heterologous graft. This paper describes some anatomical and histological characteristics of that site, as well as analyzes aspects related with its immune properties. It also focuses the advantages of this experimental model over other models which are natural or induced carriers of immunodeficiency. Based on both these advantages and literature, this study aims to establish this model, through the performance of heterologous graft, as another option for the investigation of scar disturbances, as keloids and other diseases which may interest Plastic Surgery, as benign cutaneous lesions, and malignant neoplasias such as skin carcinomas and melanomas. The work also addresses perspectives for using this model, which still is a source scarcely known by Brazilian medical class.
- ItemAcesso aberto (Open Access)Hamster (Mesocricetus auratus) cheek pouch as an experimental model to investigate human skin and keloid heterologous graft(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2004-12-01) Hochman, Bernardo [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Bôas, Flaviane Cássia Vilas [UNIFESP]; Mariano, Mario [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); São Paulo University Biomedical Sciences Institute Immunology Department; Universidade de São Paulo (USP)To describe the integration process of grafts of total human skin and keloid in hamster (Mesocricetus auratus) cheek pouch, whose sub-epithelium is naturally an Immunologically Privileged Site. Fragments of human normal skin and keloid from the breast region of mulatto female patients were transplanted into the cheek pouch subepithelium in situ. Surgical procedure and grafted pouches for microscopic exam at several time points of the transplantation were standardized. The integration of grafted fragments of human skin and keloid was seen in late periods (84 days) since the microscopic assessment showed the presence of blood vases within the conjunctive tissue of grafted fragments. It was also possible to see among the grafted fragments the epithelium, the appearing of early cellular infiltrated, epithelial secretion of keratin, the presence of melanocytes, and delayed changes on the aspect of collagen fibers of conjunctive tissue. Pooled results allow to define hamster cheek pouch sub-epithelium as an experimental model to investigating heterologous graft physiology of human total skin and keloid with epithelium.
- ItemAcesso aberto (Open Access)Integração do enxerto heterólogo de pele humana no subepitélio da bolsa jugal do hamster (Mesocricetus auratus)(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2003-10-01) Hochman, Bernardo [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Bôas, Flaviane Cássia Vilas [UNIFESP]; Mariano, Mario [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)PURPOSE: To describe the integration of total human skin into hamster (Mesocricetus auratus) cheek pouch. METHODS: The sample was formed by 18 male hamsters, outbred, aging between 10 and 14 weeks. Fragments of normal human skin were obtained from reduction mastoplasty of a mulatto woman patient. Each hamster was grafted into both pouches with skin fragments, in a total of 36 fragments grafted. Animals were distributed into 6 groups for examination of the grafted fragments at the days 5, 12, 21, 42, 84, and 168. One macroscopic assessment was performed by comparing the pouch containing the grafted fragment in each period with the same pouch in the immediate post surgical, following standardized photographs. In the microscopic assessment, as an integration criterion of the grafted skin fragments, the presence of blood vases within the dermis was adopted. The presence of keratin, melanocytes, cellular infiltrated, and the aspect of conjunctive tissue was also observed. RESULTS: In the macroscopic evaluation a vascular reaction in fragments up to 12 days and the presence of dark brown pigmentation up to 42 days were observed. Under microscope 80.64% of grafted fragments were integrated, including in the group of 168 days. An inflammatory cellular infiltrated was observed up to 12 days, the presence of melanocytes from 42 days and a subcutaneous cellular tissue hyalinization after 84 days were seen. CONCLUSIONS: Fragments of human skin integrate into the hamster pouch, they remain vascularized for 168 days and preserve the whole epithelium up to 21 days. The pouch sub-epithelium represents an experimental model to investigating human skin physiology ex vivo.
- ItemAcesso aberto (Open Access)Investigação do transplante heterólogo de quelóide na bolsa jugal do hamster (Mesocricetus auratus)(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2003-08-01) Hochman, Bernardo [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Bôas, Flaviane Cássia Vilas [UNIFESP]; Mariano, Mario [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)PURPOSE: To describe the integration of keloid heterograft into hamster (Mesocricetus auratus) sub-epithelium. METHODS: The sample is formed by 18 male hamsters, not isogenetic ones, aged between 10 and 14 weeks. Keloid fragments were obtained from keloid scars of the breast region of adult female mulatto patient. Each hamster received keloid fragments into both of its pouches, in a total of 36 grafted fragments. Animals were distributed into 6 groups for having their grafts assessed in the days 5, 12, 21, 42, 84, and 168. A macroscopic assessment is performed by comparing the pouch containing the grafted fragment, at each time point, with the same pouch in the immediate post surgical moment through a comparison of standardized photographs. Under microscope, the presence of blood vases is considered within the conjunctive tissue of the grafted fragment, as a criterion of its integration. Other events, as keratin secretion, the presence of cellular infiltrated, and epithelium and keloid collagen fibers aspects are also analyzed. RESULTS: Macroscopy reveals intensive vascularization of the pouch up to 12 days from the transplant, and the presence of constant dark brown pigmentation on the grafted keloid fragments. In microscopy the integration of keloid fragments is found by the presence of blood capillary vases within conjunctive tissue. The presence of intensive cellular inflammatory type infiltrated up to 12 days is also observed, as well as the remaining of keloid epithelium up to 21 days, and the appearing of melanocytes from the day 42. CONCLUSION: Hamster cheek pouch represents, a priori, an experimental model for the investigation of keloid.
- ItemAcesso aberto (Open Access)Keloid heterograft in the hamster (Mesocricetus auratus) cheek pouch(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2005-06-01) Hochman, Bernardo [UNIFESP]; Vilas Bôas, Flaviane Cássia [UNIFESP]; Mariano, Mario [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)PURPOSE: To study the integration of keloid heterograft in hamster (Mesocricetus auratus) cheek pouch. METHODS: The sample is formed by 18 male hamsters, heterogenic ones, aged between 10 and 14 weeks. Keloid fragments were obtained from keloid scars of the breast region of adult female mulatto patient. Each hamster received keloid fragments into both of its pouches, in a total of 36 grafted fragments. Animals were distributed into 6 groups for having their grafts assessed in the days 5, 12, 21, 42, 84, and 168. A macroscopic assessment is performed by comparing the pouch containing the grafted fragment, at each time point, with the same pouch in the immediate post surgical moment through a comparison of standardized photographs. Under microscope, the presence of blood vases is considered within the conjunctive tissue of the grafted fragment, as a criterion of its integration. Other events, as keratin secretion, the presence of cellular infiltrated, epithelium and keloid collagen fibers aspects are also analyzed. RESULTS: Macroscopy reveals intensive vascularization of the pouch up to 12 days from the transplantation and the presence of constant dark brown pigmentation on the grafted keloid fragments. In microscopy, the integration of keloid fragments is considered by the presence of blood capillary vases within conjunctive tissue. The presence of intensive cellular inflammatory type infiltrated up to 12 days is also observed, as well as the remaining of keloid epithelium up to 21 days, and the appearing of melanocytes from the day 42. CONCLUSION: Hamster cheek pouch represents, a priori, an experimental model for the investigation of keloid.
- ItemEmbargoPadrão de integração do enxerto heterólogo de pele humana e quelóide no subepitélio da bolsa jugal do hamster(Universidade Federal de São Paulo (UNIFESP), 2002) Hochman, Bernardo [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objetivo: Este trabalho visa descrever e comparar o processo de integração dos transplantes total de pele humana e quelóide no subepitélio da bolsa jugal do hamster (Mesocricetus auratus), que é um local "Local de Privilégio Imunológico". Métodos: Foram formados 2 grupos experimentais, sendo transplantadas, por grupo, amostras de pele e quelóide em ambas as bolsas de 18 hamsters, perfazendo um total 36 transplantes de cada amostra. Os animais foram subdivididos em 6 subgrupos para análise dos transplantes com 5, 12, 21, 42, 84 e 168 dias. O principal critério de integração adotado, foi a presença de vasos sangüíneos com hemácias nos transplantes. Na análise macroscópica dos transplantes foram observadas as reações vasculares na bolsa e a presença de pigmentações. A análise microscópica incluiu a avaliação da vascularização, a presença de infiltrado inflamatório e melanócitos, e as condições do epitélio e do tecido conjuntivo dos transplantes. Resultados: Integraram 80,64% dos transplantes de pele e 72,41% de quelóide. A macroscopia revelou uma reação vascular nos enxertos até 12 dias, sendo mais intensa nas amostras de quelóide, e a presença de pigmentação nos enxertos de pele e quelóide a partir de 42 dias. No exame histológico houve a presença de infiltrado inflamatório em ambos os grupos experimentais até 12 dias, sendo mais intenso no quelóide. Registrou-se a presença de melanócitos na pele e no quelóide a partir de 42 dias, e houve uma hialinização mais precoce, com 42 dias, do tecido conjuntivo nos enxertos de quelóide, em relação aos de pele que ocorreu a partir de 84 dias, porém com a manutenção de vasos em ambos os casos. Conclusões: A bolsa jugal do hamster pode ser utilizada como modelo experimental para enxertos de pele humana e quelóide, com manutenção da integridade dos epitélios, para estudos de até 21 dias. O modelo também mostrou-se útil para estudos de até 168 dias sem a presença de epitélio íntegro. Os enxertos de quelóide apresentaram um fator pró-inflamatório mais intenso que os enxertos de pele até 12 dias. A bolsa do hamster propiciou ao transplante de quelóide, ineditamente, a diferenciação de melanócitos, ausentes nas lesões no ser humano.