RESUMO
The formation of incisors and canines in marsupials of D. albiventris was studied at various stages of development. Seventy-six specimens, with ages varying from 0 to 100 days, were used in this investigation. Serial sections of the maxilla were obtained in the transverse plane and stained with hematoxylin and eosin. Histological analyses were made to verify the pattern of teeth development, as well as their chronology of eruption. The period of time from birth to 100 days comprised the entire process of teeth development, from epithelial bud formation to early eruption of the teeth. Oral epithelium thickening gave rise to the functional incisors and canines. In addition, a secondary dental lamina emerged in different phases of development in the outer epithelium of incisors and canines, which degenerated when it reached the bud stage. No evidence of deciduous dentition was observed. The results of this investigation suggest that secondary dental lamina represents remnants of a primitive condition in which secondary dentition used to be present.
Estudou-se o desenvolvimento dos dentes incisivos e caninos em 76 amostras de Didelphis albiventris com idade entre 0 e 100 dias. Cortes transversais, seriados de 6 µm de espessura foram obtidos da região da maxila, corados com Hematoxilina e Eosina e analisados ao microscópio de luz. Verificou-se que o período estudado abrange todo o desenvolvimento dental, desde a fase de iniciação da interação epitélio/mesenquima até a completa formação e erupção dos incisivos e caninos. O espessamento do epitélio oral dá origem aos incisivos e caninos funcionais, enquanto o epitélio dental externo do órgão dental origina uma lâmina dental secundária, a qual sofre degeneração, quando o dente alcança o estágio de botão. Não há vestígios de dentição decídua. Sugere-se que a lâmina dental secundária é remanescente de uma condição primitiva na qual ocorria dentição secundária.
RESUMO
Laboratory profile of young ovines was studied in order to evaluate and compare their antiserum production from natural and Cobalt-60 irradiated Crotalus durissus terrificus (C.d.t.) venoms. The parameters analyzed included complete blood count, and urea, creatinine, aspartate aminotransferase, total proteins, albumin and globulin serum measurements. Three groups of six animals each were used. Group 1 (G1) received natural C.d.t. venom; Group 2 (G2) received irradiated C.d.t. venom; and Group 3 (G3) was used as control and did not receive venom, only adjuvants, using seven venom inoculations. During the experimental period, animals were fortnightly weighed. According to clinical and weight evaluation, sheep in post-weaning phase showed no changes in their physiological profiles but had excellent weight gain. The parameters analyzed were not statistically different (p 5%) among the groups tested. The hyperimmunization process was successfully accomplished with the production of specific antibodies against Crotalus durissus terrificus venom. Results bring a new possibility of utilizing ovines in the commercial production of anticrotalic serum, which may be used to treat human and animal envenomation. Its production cost may be reduced by subsequent use of hyperimmunized sheep for human consumption.
RESUMO
The formation of incisors and canines in marsupials of D. albiventris was studied at various stages of development. Seventy-six specimens, with ages varying from 0 to 100 days, were used in this investigation. Serial sections of the maxilla were obtained in the transverse plane and stained with hematoxylin and eosin. Histological analyses were made to verify the pattern of teeth development, as well as their chronology of eruption. The period of time from birth to 100 days comprised the entire process of teeth development, from epithelial bud formation to early eruption of the teeth. Oral epithelium thickening gave rise to the functional incisors and canines. In addition, a secondary dental lamina emerged in different phases of development in the outer epithelium of incisors and canines, which degenerated when it reached the bud stage. No evidence of deciduous dentition was observed. The results of this investigation suggest that secondary dental lamina represents remnants of a primitive condition in which secondary dentition used to be present.
Estudou-se o desenvolvimento dos dentes incisivos e caninos em 76 amostras de Didelphis albiventris com idade entre 0 e 100 dias. Cortes transversais, seriados de 6 µm de espessura foram obtidos da região da maxila, corados com Hematoxilina e Eosina e analisados ao microscópio de luz. Verificou-se que o período estudado abrange todo o desenvolvimento dental, desde a fase de iniciação da interação epitélio/mesenquima até a completa formação e erupção dos incisivos e caninos. O espessamento do epitélio oral dá origem aos incisivos e caninos funcionais, enquanto o epitélio dental externo do órgão dental origina uma lâmina dental secundária, a qual sofre degeneração, quando o dente alcança o estágio de botão. Não há vestígios de dentição decídua. Sugere-se que a lâmina dental secundária é remanescente de uma condição primitiva na qual ocorria dentição secundária.
RESUMO
ELISA was used to evaluate, accompany, and compare the humoral immune response of Swiss mice during hyperimmunization with native and Cobalt-60-irradiated (60Co) venoms of Bothrops jararaca, Bothrops jararacussu and Bothrops moojeni. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by in vivo challenge, and the side effects were assessed. The animals immunization with one LD50 of each venom occurred on days 1, 15, 21, 30, and 45, when blood samples were collected; challenges happened on the 60th day. Results showed that ELISA was efficient in evaluating, accompanying and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co-irradiation. The sera produced with native venom showed neutralizing potency and capacity similar to those of the sera produced with irradiated venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom, however, necrosis and death occurred in animals inoculated with native venom.
RESUMO
ELISA was used to evaluate, follow, and compare the humoral immune response of Swiss mice during hyperimmunization with natural and Cobalt 60-irradiated (60Co) Crotalus durissus terrificus venom. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by "in vivo" challenge and the side effects were assessed. The animals immunization with one LD50 of the venom was on days one, 15, 21, 30, and 45, when blood samples were collected; the challenges occurred on the 60th day. Results showed that ELISA was efficient in evaluating, following, and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co irradiation. Serum produced from Crotalus durissus terrificus irradiated venom showed higher potency and neutralization capacity than that from natural venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom.