PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Arana S., Dagli M.L.Z, Sabino M., Tabata Y.A., Rigolino M.G. & Hernandez-Blazquez F.J. 2011. Evaluation of the efficacy of hydrated sodium aluminosilicate in the prevention of aflatoxin-induced hepatic cancer in rainbow trout. Pesquisa Veterinária Brasileira 31(9):751-755. Laboratório de Histofisiologia e Histopatologia Experimental em Animais Ectotérmicos, Departamento de Histologia e Embriologia, Instituto de Biologia, Universidade Estadual de Campinas, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: aranas@unicamp.br The use of aluminum silicates for decontaminating animal feed containing aflatoxins has yielded encouraging results in chicken and turkey poults. In contrast, very few studies have tested these substances in aquaculture. In this work, we investigated the efficacy of a trout diet containing 0.5% hydrated sodium aluminosilicate (HSAS) in protecting against contamination with aflatoxin B1. Trout were reared on these diets for one year and the experimental groups were examined monthly for hepatic presumptive preneoplastic and neoplastic lesions. Regardless of the presence of HSAS, all of the fish that received aflatoxin in their diet have shown hepatic lesions indicative of a carcinogenic process, presenting also the development of cancer in some fish. The concentration of HSAS used in this study was ineffective in preventing the onset of hepatic lesions induced by aflatoxin B1 in rainbow trout.

• Sodium aluminosilicate aflatoxin hepatocarcinogenesis aluminosilicato de sódio aflatoxina hepatocarcinogênese

Abstract in Portuguese:

RESUMO.- Arana S., Dagli M.L.Z, Sabino M., Tabata Y.A., Rigolino M.G. & Hernandez-Blazquez F.J. 2011. Evaluation of the efficacy of hydrated sodium aluminosilicate in the prevention of aflatoxin-induced hepatic cancer in rainbow trout. [Avaliação da eficácia do aluminosilicato de sódio hidratado na prevenção de câncer hepático induzido por aflatoxina em truta arco-íris.] Pesquisa Veterinária Brasileira 31(9):751-755. Laboratório de Histofisiologia e Histopatologia Experimental em Animais Ectotérmicos, Departamento de Histologia e Embriologia, Instituto de Biologia, Universidade Estadual de Campinas, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: aranas@unicamp.br Resultados encorajadores têm sido observados com o emprego de aluminosilicatos para descontaminação de ração contendo aflatoxina destinada à avicultura. No entanto, raros estudos têm sido destinados a testar essa substância em aqüicultura. Assim, no presente trabalho, foi investigada a eficácia do aluminosilicato de sódio hidratado (HSAS, 0,5%) em proteger a truta arco-íris dos danos hepáticos causados por ração contaminada com aflatoxina B1. Os grupos experimentais foram alimentados com suas respectivas dietas durante 12 meses, mensalmente cada grupo foi amostrado para análises anatomopatológica e histopatológica para verificação da presença de lesões hepáticas. Apesar da presença de HSAS, todos os grupos que receberam dieta contaminada com aflatoxina B1 apresentaram lesões hepáticas indicativas do processo carcinogênico, sendo que exemplares alimentados com essas dietas por mais longo prazo apresentaram hepatocarcinoma ou colangiocarcinoma. Estes resultados indicaram que a concentração de HSAS usada no presente estudo não foi efetiva em prevenir o desenvolvimento de lesões hepáticas induzidas por aflatoxina B1 em truta arco-íris.

Abstract in English:

ABSTRACT.- Silva A.P., Silva R.G., Cogliati B., Dias A.S.M., Le Bas A.E. & Hernandez-Blazquez F.J. 2011. Bleaching of melanin in the epidermis of South American fur seal and its application on enzyme immunohistochemistry. [Clareamento da melanina na epiderme do Lobo-marinho-sul-americano e sua aplicação na imuno-histoquímica enzimática.] Pesquisa Veterinária Brasileira 31(3):267-270. Setor de Anatomia dos Animais Domésticos e Silvestres, Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 055508-900, Brazil. E-mail: paulasilvabio@usp.br The South American fur seal (Arctocephalus australis) is an amphibious marine mammal distributed along the Atlantic and Pacific coasts of South America. The species is well adjusted to different habitats due to the morphology of its fin-like members and due to some adaptations in their integumentary system. Immunohistochemical studies are very important to evaluate the mechanisms of skin adaptation due the differential expression of the antigens present in the tissue depending of the region of the body surface. However, its strongly pigmented (melanin) epidermis prevents the visualization of the immuno-histochemical chromogens markers. In this study a melanin bleaching method was developed aimed to allow the visualization of the chromogens without interfering in the antigen-antibody affinity for immunohistochemistry. The analysis of PCNA (proliferating cell nuclear antigen) index in the epidermis of A. australis by immunohistochemistry with diaminobenzidine (DAB) as chromogen was used to test the method. The bleaching of the melanin allowed to obtain the cell proliferation index in epidermis and to avoid false positive results without affecting the immunohistochemical results.

• Fur seal skin melanin Arctocephalus australis lobo-marinho pele melanina

Abstract in Portuguese:

RESUMO.- Silva A.P., Silva R.G., Cogliati B., Dias A.S.M., Le Bas A.E. & Hernandez-Blazquez F.J. 2011. Bleaching of melanin in the epidermis of South American fur seal and its application on enzyme immunohistochemistry. [Clareamento da melanina na epiderme do Lobo-marinho-sul-americano e sua aplicação na imuno-histoquímica enzimática.] Pesquisa Veterinária Brasileira 31(3):267-270. Setor de Anatomia dos Animais Domésticos e Silvestres, Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 055508-900, Brazil. E-mail: paulasilvabio@usp.br O Lobo-marinho-sul-americano (Arctocephalus australis) é um mamífero marinho anfíbio distribuído ao longo da Costa do Atlântico e do Pacífico da América do Sul. Esta espécie está bem adaptada a diferentes habitats devido à morfologia dos membros em forma de nadadeira e de seu sistema tegumentar. Estudos imuno-histoquímicos são importantes para avaliar os mecanismos de adaptação da pele devido a diferencial expressão dos antígenos presentes no tecido dependendo da região da superfície corporal. Entretanto, sua epiderme altamente pigmentada (melanina) impede a visualização dos marcadores cromógenos utilizados na imuno-histoquímica. Neste trabalho foi desenvolvido um método de clarear a melanina para permitir a visualização dos cromógenos sem alterar a afinidade antígeno-anticorpo para a imuno-histoquímica. A análise do índice do PCNA (proliferating cell nuclear antigen) na epiderme de A. australis, com diaminobenzidina (DAB) como cromógeno foi usada para testar o método. O clareamento da melanina permitiu obter o índice de proliferação celular na epiderme e evitar resultados falso-positivos sem afetar os resultados imuno-histoquímicos.

Abstract in English:

ABSTRACT.- Rodrigues G.C., Oliveira L.J., Monteiro J.M., Lima A.R., Gonçalez P.O., Hernandez-Blazquez F.J., Leiser R. & Kfoury Jr J.R. 2010. Ultrastructural characterization of bovine umbilical cord blood cells. [Caracterização ultra-estrutural das células sanguíneas do cordão umbilical bovino.] Pesquisa Veterinária Brasileira 30(10):897-902. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, Av. Prof. Dr. Orlando de Marques Paiva 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil. E-mail: jrobertok@usp.br The umbilical cord blood (UCB) is an important source of pluripotent stem cells, which motivated researches on ontogeny and transplantation. The morphological characterization of umbilical cord cells is the first step to establish subsequent experiments on these areas. Although some information on humans can be found, no data on UCB is available for bovines. Therefore, this work is the first attempt to conduct an ultrastructural characterization of bovine umbilical cord blood. Blood was collected from the umbilical cord of twenty fetuses by punction of the umbilical vein. Samples were processed for whole leucocytes observation by centrifugation and the buffy coat was collected. Cells were washed and pelleted and prepared according to the standard protocol of the transmission electron microscopy. The presence of cells with morphologic characteristics compatible with the precursors from the erythrocytic, neutrophilic, eosinophilic, basophilic, and lymphocytic lineages was observed. Atypical cells with peculiar morphological features, strongly similar to apoptotic cells, were seen. Bovine neutrophils with three types of cytoplasmic granules were also found in the blood. The ultrastructural characteristics of observed bovine UCB cells where similar to those found in other species, suggesting that bovines could possibly constitute an experimental model for approaches on UCB cells research.

• Umbilical cord blood cells haematopoietic progenitor cells cordão umbilical células progenitoras hematopoiéticas

Abstract in Portuguese:

RESUMO.- Rodrigues G.C., Oliveira L.J., Monteiro J.M., Lima A.R., Gonçalez P.O., Hernandez-Blazquez F.J., Leiser R. & Kfoury Jr J.R. 2010. Ultrastructural characterization of bovine umbilical cord blood cells. [Caracterização ultra-estrutural das células sanguíneas do cordão umbilical bovino.] Pesquisa Veterinária Brasileira 30(10):897-902. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, Av. Prof. Dr. Orlando de Marques Paiva 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil. E-mail: jrobertok@usp.br O sangue de cordão umbilical (SCU) é uma importante fonte de células progenitoras pluripotentes, que motiva pesquisas em ontogenia e transplantes. A caracterização morfológica das células de cordão umbilical é o primeiro passo para se estabelecer experimentos subsequentes nessas áreas. Embora algumas informações sobre SCU em humanos possam ser encontradas, não existe nenhuma informação disponível sobre elas em bovinos. Portanto, este trabalho é a primeira tentativa de se conduzir uma caracterização ultra-estrutural do sangue de cordão umbilical bovino. O sangue foi coletado do cordão umbilical de 20 fetos por punção da veia umbilical. As amostras foram processadas para observação dos leucócitos totais por centrifugação pela coleta do botão leucocitário. As células foram lavadas, peletizadas e preparadas de acordo com protocolo padrão para microscopia eletrônica de transmissão. A presença de células com características morfológicas compatíveis com precursores das linhagens eritrocítica, neutrofílica, eosinofílica, basofílica e linfocítica foram observadas. Células atípicas com características morfológicas peculiares muito semelhantes a células em apoptose foram observadas. No sangue do cordão umbilical também foi encontrado neutrófilos bovinos apresentando três tipos de grânulos citoplasmáticos. As características ultra-estruturais do SCU bovino foram semelhantes às encontradas em outras espécies, sugerindo que esta espécie possa servir como modelo experimental para abordagens em pesquisas sobre sangue de cordão umbilical.

Abstract in English:

ABSTRACT.- Santos-Rodrigues A., Dagli M.L.Z., Avanzo J.L., Moraes H.P., Mackowiak I.I. & Hernandez-Blazquez F.J. 2009. Expression and distribution of connexin 32 in rat liver with experimentally induced fibrosis. Pesquisa Veterinária Brasileira 29(4):353-357. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: alexsantos@usp.br The connexin 32 (Cx32) is a protein that forms the channels that promote the gap junction intercellular communication (GJIC) in the liver, allowing the diffusion of small molecules through cytosol from cell-to-cell. Hepatic fibrosis is characterized by a disruption of normal tissue architeture by cellular lesions, and may alter the GJIC. This work aimed to study the expression and distribution of Cx32 in liver fibrosis induced by the oral administration of dimethylnitrosamine in female Wistar rats. The necropsy of the rats was carried out after five weeks of drug administration. They presented a hepatic fibrosis state. Sections from livers with fibrosis and from control livers were submitted to immunohistochemical, Real Time-PCR and Western-Blot analysis to Cx32. In fibrotic livers the Cxs were diffusely scattered in the cytoplasm, contrasting with the control livers, where the Cx32 formed junction plaques at the cell membrane. Also it was found a decrease in the gene expression of Cx32 without reduction in the protein quantity when compared with controls. These results suggest that there the mechanism of intercellular communication between hepatocytes was reduced by the fibrotic process, which may predispose to the occurrence of a neoplastic process, taken in account that connexins are considered tumor suppressing genes.

• Dimethylnitrosamine fibrosis liver Cx32 gap junctions

Abstract in Portuguese:

ABSTRACT.- Santos-Rodrigues A., Dagli M.L.Z., Avanzo J.L., Moraes H.P., Mackowiak I.I. & Hernandez-Blazquez F.J. 2009. Expression and distribution of connexin 32 in rat liver with experimentally induced fibrosis. Pesquisa Veterinária Brasileira 29(4):353-357. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: alexsantos@usp.br The connexin 32 (Cx32) is a protein that forms the channels that promote the gap junction intercellular communication (GJIC) in the liver, allowing the diffusion of small molecules through cytosol from cell-to-cell. Hepatic fibrosis is characterized by a disruption of normal tissue architeture by cellular lesions, and may alter the GJIC. This work aimed to study the expression and distribution of Cx32 in liver fibrosis induced by the oral administration of dimethylnitrosamine in female Wistar rats. The necropsy of the rats was carried out after five weeks of drug administration. They presented a hepatic fibrosis state. Sections from livers with fibrosis and from control livers were submitted to immunohistochemical, Real Time-PCR and Western-Blot analysis to Cx32. In fibrotic livers the Cxs were diffusely scattered in the cytoplasm, contrasting with the control livers, where the Cx32 formed junction plaques at the cell membrane. Also it was found a decrease in the gene expression of Cx32 without reduction in the protein quantity when compared with controls. These results suggest that there the mechanism of intercellular communication between hepatocytes was reduced by the fibrotic process, which may predispose to the occurrence of a neoplastic process, taken in account that connexins are considered tumor suppressing genes.

Abstract in English:

ABSTRACT.- Agreste F.R., Bombonato P.P. & Hernandez-Blazquez, F.J. 2007. [Morphometric characteristics of thymus development in dogs.] Características morfométricas do desenvolvimento do timo em cães. Pesquisa Veterinária Brasileira 27(6):236-240. Departamento de Cirurgia, Setor de Anatomia dos Animais Domésticos e Silvestres, Universidade de São Paulo, Avenida Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-000, Brazil. E-mail: bombonat@usp.br The thymus is an organ with great immunological relevance during foetus life and neonatal period, It is the predecessor of lymphopoiesis and shows high lymphopoietic activity, being also the largest lymphoid organ during intrauterine life and at birth. In this study, the morphological aspects of the prenatal development of dog thymus were described in foetus of different ages and sexes. Twenty-four foetus of mongrel domestic dogs, males and females, were divided into four age groups. The thymus presented two lobes linked by a rose-colored tissue connection that was localized in the cranial mediastinal space. The cranial portion protrudes slightly beyond the first pair of ribs. The cells that formed the thymus parenchyma were well organized. Concentric aggregates named Hassal corpuscles were observed, involved by a thin capsule of connective tissue thickened by adipose tissue. The vessels size gradually increased with the foetus age, being larger in animals that were closer to birth. The volume (Vref) and size parameters of female thymus were larger than in males.

• Thymus vascularization lymphatic system morphometry dogs

Abstract in Portuguese:

ABSTRACT.- Agreste F.R., Bombonato P.P. & Hernandez-Blazquez, F.J. 2007. [Morphometric characteristics of thymus development in dogs.] Características morfométricas do desenvolvimento do timo em cães. Pesquisa Veterinária Brasileira 27(6):236-240. Departamento de Cirurgia, Setor de Anatomia dos Animais Domésticos e Silvestres, Universidade de São Paulo, Avenida Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-000, Brazil. E-mail: bombonat@usp.br The thymus is an organ with great immunological relevance during foetus life and neonatal period, It is the predecessor of lymphopoiesis and shows high lymphopoietic activity, being also the largest lymphoid organ during intrauterine life and at birth. In this study, the morphological aspects of the prenatal development of dog thymus were described in foetus of different ages and sexes. Twenty-four foetus of mongrel domestic dogs, males and females, were divided into four age groups. The thymus presented two lobes linked by a rose-colored tissue connection that was localized in the cranial mediastinal space. The cranial portion protrudes slightly beyond the first pair of ribs. The cells that formed the thymus parenchyma were well organized. Concentric aggregates named Hassal corpuscles were observed, involved by a thin capsule of connective tissue thickened by adipose tissue. The vessels size gradually increased with the foetus age, being larger in animals that were closer to birth. The volume (Vref) and size parameters of female thymus were larger than in males.

Abstract in English:

ABSTRACT.- Rodrigues M.A.M., Oliveira D.A., Taketomi E.A. & Hernandez-Blazquez F.J. 2007. IgA production, coliforms analysis and intestinal mucosa morphology of piglets that received probiotics with viable or inactivated cells. Pesquisa Veterinária Brasileira 27(6):241-245. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. Email: fjhblazq@usp.br Two types of probiotics were used in piglets. One product is a mixed culture of viable Lactobacillus acidophilus, Enterococcus faecium e Bifidobacterium bifidum. The second product is composed of inactivated Lactobacillus acidophilus cells. The piglets received two weekly oral doses for 30 days while a control group did not receive probiotics. All piglets were euthanized at the 30th day of life and the mesenteric lymph nodes, the small intestine, and blood samples were collected. The tissue samples were studied by light microscopy and the blood serum was analyzed by ELISA method. The treatment with the probiotic with viable cells produced higher serum levels of IgA (P<0.05) and more IgA expressing cells were found in the mesenteric lymph nodes than observed in the inactivated cells treatment or control groups (P<0.05). Also, intestinal villi were longer, crypts were deeper (P<0.05) and fecal coliform count was lower than found in the inactivated product (P<0.05). These results suggest that viable probiotics are more efficient than inactivated probiotics to induce immunostimulation and intestinal modifications in piglets, thus improving their health and development.

• Probiotics IgA piglets swine weaning Lactobacillus intestine

Abstract in Portuguese:

ABSTRACT.- Rodrigues M.A.M., Oliveira D.A., Taketomi E.A. & Hernandez-Blazquez F.J. 2007. IgA production, coliforms analysis and intestinal mucosa morphology of piglets that received probiotics with viable or inactivated cells. Pesquisa Veterinária Brasileira 27(6):241-245. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. Email: fjhblazq@usp.br Two types of probiotics were used in piglets. One product is a mixed culture of viable Lactobacillus acidophilus, Enterococcus faecium e Bifidobacterium bifidum. The second product is composed of inactivated Lactobacillus acidophilus cells. The piglets received two weekly oral doses for 30 days while a control group did not receive probiotics. All piglets were euthanized at the 30th day of life and the mesenteric lymph nodes, the small intestine, and blood samples were collected. The tissue samples were studied by light microscopy and the blood serum was analyzed by ELISA method. The treatment with the probiotic with viable cells produced higher serum levels of IgA (P<0.05) and more IgA expressing cells were found in the mesenteric lymph nodes than observed in the inactivated cells treatment or control groups (P<0.05). Also, intestinal villi were longer, crypts were deeper (P<0.05) and fecal coliform count was lower than found in the inactivated product (P<0.05). These results suggest that viable probiotics are more efficient than inactivated probiotics to induce immunostimulation and intestinal modifications in piglets, thus improving their health and development.