Evaluation of histological changes after tracheal occlusion at different gestational ages in a fetal rat model

OBJECTIVES: To evaluate the histological changes of tracheal cartilage and epithelium caused by tracheal occlusion at different gestational ages in a fetal rat model. METHODS: Rat fetuses were divided into two groups: a) External control, composed of non-operated rats, and b) Interventional group, composed of rats operated upon on gestational day 18.5 (term = 22 days), divided into triads: 1) Tracheal occlusion, 2) Internal control and 3) Sham (manipulated but not operated). Morphological data for body weight, total lung weight and total lung weight/body weight ratio were collected and measured on gestational days 19.5, 20.5 and 21.5. Tracheal samples were histologically processed, and epithelial, chondral and total tracheal thicknesses were measured on each gestational day. RESULTS: The tracheal occlusion group exhibited an increase in total lung weight/body weight ratio (

A nova improbidade administrativa

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 35.077.3(81)(094) Coment. N935

Immunohistochemical staining of the macrophagic and astrocytic response in the brainstem of Wistar rats submitted to the ethidium bromide gliotoxic model and treated with cyclophosphamide

The gliotoxic ethidium bromide (EB) was used to study morphologically the macrophagic and astrocytic response under immunosuppression by cyclophosphamide (CY). Astrocyte immunoreactivity to glial fibrillary acidic protein (GFAP) and vimentin (VIM) and macrophagic immunoreactivity to ED1 were investigated after EB injection. Male Wistar rats were injected with 0.9% saline solution (group I), 0.1% BE (group II) and 0.1% EB associated with CY treatment (group III). Brainstem samples were collected from the 1st to the 21st day post-injection for GFAP, VIM and ED1 immunostaining. In groups II and III, it was observed increased immunoreactivity to GFAP and reexpression of VIM. In group II, ED1-positive cells were noted after the 2nd day and in group III, after the 3rd day. On the 14th day post-injection, it was observed a greater quantity of ED1- positive cells in group III than in group II. Apparently, CY did not change the astrocytic response pattern.O gliotóxico brometo de etídio (BE) foi utilizado para o estudo da resposta macrofágica e astrocitária sob imunossupressão com ciclofosfamida (CY). Investigou-se a imunorreatividade astrocitária à proteína glial fibrilar ácida (GFAP) e à vimentina (VIM), e a imunorreatividade macrofágica ao ED1 após injeção do BE. Foram utilizados ratos Wistar adultos injetados na cisterna basal com salina a 0,9% (grupo I), BE a 0,1% (grupo II) e BE a 0,1%, imunossuprimidos com CY (grupo III). Fragmentos do tronco encefálico foram colhidos do 1º ao 21º dia pós-injeção para estudo imuno-histoquímico da GFAP, VIM e ED1. Nos grupos II e III, observou-se imunorreatividade aumentada para GFAP e re-expressão de VIM. No grupo II, células ED1-positivas foram observadas a partir do 2º dia e no grupo III, a partir do 3º dia. Aos 14 dias pós-injeção, havia mais células ED1-positivas no grupo III. A CY aparentemente não alterou a resposta astrocitária.78779

Efeitos do brometo de etidio no tronco cerebral de ratos Wistar : aspectos morfologicos relacionados aos processos de desmielinização e remielização do sistema nervoso central

Orientador: Maria Alice da Cruz HoflingDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Face à dificuldade do estudo de material humano, muitos modelos experimentais, que mimetizam doenças desmielinizantes, têm sido utilizados no estudo das características celulares da desmielinização e da limitada remielinização do sistema nervoso central. O objetivo desta investigação foi estudar o fenômeno desmielinizante causado pela droga intercalante brometo de etídio (BE), bem como o conseqüente processo de remielinização, no tronco cerebral de ratos Wistar adultos. Foram utilizados 34 animais divididos em grupo I (3 animais) utilizados para as análises histológica e ultraestrutural da porção ventral da ponte, grupo 11 (21 animais) que receberam uma única injeção de 1O,u1 (0,1 % de BE em solução salina 0,15M) na cisterna basal, e grupo 111 (10 animais) que receberam uma única injeção de 10 ,ul de solução salina 0,15M. Do grupo 11, 3 animais foram perfundidos (1 para histologia e 2 para ultraestrutura) nos seguintes intervalos de tempo (dias): 1,3,7, 11, 15,21 e 30. Do grupo 111, 2 animais foram perfundidos (1 para histologia e 2 para ultraestrutura) até o período de 15 dias. No grupo 11, lesões desmielinizantes foram encontradas principalmente na superfície ventral da ponte e se estendem de 1/3 a 1/2 na estrutura em sentido dorsal e posteriormente constituem formações císticas. As lesões eram caracterizadas por espongiose do tecido nervoso confirmados à microscopia eletrônica de transmissão por cariorréxis das células gliais, severas alterações citoplasmáticas, formação de figuras de "honey comb", vesículas de mielina e grande aumento do espaço extracelular. Aos 3 dias, a lesão apresentava-se povoada por células fagocíticas que iniciavam a remoção dos restos de mielina. A remielinização ficava confinada à periferia da lesão e era iniciada pelos oligodendrócitos aos 11 dias. Embora neste mesmo período as células de Schwann estivessem relacionadas com axônios, a produção de mielina por essas células só foi evidenciada aos 15 dias após a injeção do BE. Na área de remielinização os oligodendrócitos estavam sempre associados a nichos de fibras desmielinizadas onde eram evidentes processos citoplasmáticos astrocitários, por outro lado, as células de Schwann apresentavam-se associadas apenas a fibras individualizadas que não estivessem relacionadas com processos astrocitários. Nesta investigação a remielinização do encéfalo foi significativamente realizada por oligodendrócitos, e na ausência de processos astrocitários as células de Schwann remielinizantes migravam para a lesão, e não se relacionavam obrigatoriamente com os espaços perivasculares e subpiais. Provavelmente a astrocitose, per se, não deve ser responsabilizada pelo impedimento da remielinização por oligodendrócitosAbstract: The difficulty to study human tissue, had led to the development of many experimental models, that mimic the nervous system demyelinating diseases. The models have contributed to the understanding of many cellular events involving the demyelination as well as the limited remyelination of the central nervous system. The objective of this investigation was to study the process of demyelination caused by the intercalant drug ethidium bromide (EB) , as well as the consequent remyelination in the brainstem of Wistar adult rats. It were utilized 34 animaIs divided into group 1 (3 animaIs) as used for histologycal and ultrastructural analyses of the ventral part of the pons, the group 11 (21 animaIs) received a single injection of 10 #1 (EB/O,l % of 0,15M saline) into the basal cisterna; the group 111 (10 animaIs) that received a single injection of 10 #1 of saline solution 0,15M. In the group 11 3 animaIs were perfused (1 for histology and 2 for ultrastructure) in time intervals (days): 1,3, 7, 11 and 15 days after EB injection. In the group 111,. Demyelinated lesions were found find mainly in the ventral surface of the pons and extended by 1/3 to 1/2 along the dorsal direction and later on constitute cystic formations. The lesions were characterized by status spongiosus on the nervous tissue, which is corroborated by ultrastructural observations showing cariorrexis of the glial cells, severe cytoplasmic alterations, honey comb formation, myelin vesicculation and finally loss of the myelin by the axons and widening of extracellular space. After 3 days the lesion is invaded by phagocytic cells that began the removal of myelin debris.The remyelination was confined to the periphery of the lesion and began with the oligodendrocytes by 11 days by this time the Schwann cells were already connected with axons, but myelin production only began by 15 days after EB injection. In the remyelinated area the oligodendrocytes were always associated with groups of demyelinated tibers, where are evident in between several cytoplasmic astrocytic processes, on the hand, the Schwann cells were seen associated with individualized fibers without any contact with astrocytes processes. In this model, the encephalic remyelination was chiefly carryed out by oligodendrocytes. In the absence of the astrocytic processes the remyelinating Schwann cells, migrate to the lesioned areaMestradoBiologia CelularMestre em Ciências Biológica

Desmielinização e remielinização após múltiplas injeções intramedulares de brometo de etídio em ratos Wistar Demyelination and remyelination after multiple intramedullary injections of ethidium bromide in Wistar rats

O modelo de desmielinização do brometo de etídio foi utilizado para estudar a reação do sistema nervoso central frente a múltiplos episódios de desmielinização tóxica. Foram utilizados 27 ratos Wistar, submetidos a 2,3 ou 4 injeções de 1μl de solução 0,1 % de brometo de etídio (19 ratos) ou de solução salina 0,9% (8 ratos) em diferentes pontos da medula espinhal. Os intervalos entre as injeções variaram de 28 a 42 dias. Dez dias após a última injeção os animais foram perfundidos com glutaraldeído 2,5%. As medulas espinhais foram avaliadas pela macroscopia, microscopia óptica de cortes semifinos e microscopia eletrônica de transmissão. As lesões foram caracterizadas por desmielinização primária focal, com preservação das estruturas vasculares, e variavam em tamanho e características histológicas. Remielinização pode ser observada, ou não, de acordo com o tipo de lesão. Como conseqüência das injeções múltiplas e seqüenciais de brometo de etídio, o sistema nervoso central pareceu modificar sua capacidade de responder a um estímulo inflamatório, mas não variou seu padrão de remielinização.The ethidium bromide model of demyelination has been employed to study the central nervous system response to several episodes of demyelination. Twenty-seven Wistar rats received 2 to 4 intraspinal injections of lμl of either 0.1% ethidium bromide in normal saline (19 rats) or saline 0.9% (8 rats) in different anatomical locations. The intervals between the injections ranged from 28 to 42 days. Ten days after the last injection all the rats were perfused with 2.5% glutaraldehyde. The spinal sections were evaluated macroscopically and by light and transmission electron microscopy. The lesions were typical of focal primary demyelination with preserved vascular structures and followed by remyelinization and varied in size and histological aspects. After multiple sequential ethidium bromide injections, the central nervous system seems to modify its response capacity to an inflammatory challenge although there is no change in its pattern of remyelination

Prototipagem como forma alternativa para realização de cranioplastia com metilmetacrilato: nota técnica Prototyping as an alternative to cranioplasty using methylmethacrylate: technical note

A prototipagem, método de reconstrução de segmentos do corpo humano através de programas de computação, tem sido usada na neurocirurgia para reproduzir o crânio de pacientes permitindo a programação de atos cirúrgicos e a produção de próteses para reconstruir falhas ósseas no crânio. Apresentamos dois casos de cranioplastia realizadas com o uso de próteses de acrílico construídas por prototipagem. Após 10 meses de acompanhamento, os pacientes não apresentaram sinais de infecção e apresentam bom resultado estético. As vantagens apontadas na literatura para este método (redução do tempo cirúrgico, facilidade técnica e bom resultado estético) foram observadas.The prototyping is a method for reconstruction of human body segments by computer software. It has been used in neurosurgery for cranial reproduction in patients allowing the programming of surgical procedures and the production of prosthesis to reconstruct bone failures in the skull. We present two cases of cranioplasty performed with the use of acrylic prosthesis constructed by prototyping. After 10 months of follow-up, they donot present signs of infection and show good aesthetic result. The advantages pointed at the literature for this method (reduction of surgical time, easy technical handle, and good aesthetic result) were confirmed

Is peripheral blood cell balanced altered by the use of fresh frozen bone block allografts in lateral maxillary ridge augmentation?

Background: The relationship between the immune response and red and white blood cell homeostasis is cited in literature, but no studies regarding the balance of these cell populations following maxillary bone-graft surgeries can be found. Aim: The aim of this study was to evaluate the possible impairments in the blood cell balance following fresh-frozen allogeneic bone-graft augmentation procedures in patients who needed maxillary reconstruction prior to implants. Material and Methods: From 33 patients elected to onlay bone grafting procedures, 20 were treated with fresh-frozen bone allografts and 13 with autologous bone grafts. Five blood samples were collected from each patient in a 6-month period (baseline: 14, 30, 90, and 180 days postsurgery), and the hematological parameters (erythrogram, leukogram, and platelets count) were accessed. Results: All evaluated parameters were within the reference values accepted as normal, and significant differences were found for the eosinophils count when comparing the treatments (30 days, p=.035) and when comparing different periods of evaluation (allograft-treated group, baseline×180 days, p≤.05 and 90×180 days, p≤.01; autograft-treated group, 30×90 days, p≤.05 and 30×180 days, p≤.05). Conclusions: Both autologous and fresh-frozen allogeneic bone grafts did not cause any impairment in the red and white blood cell balance, based on quantitative hemogram analysis, in patients subjected to maxillary reconstruction. © 2011 Wiley Periodicals, Inc

Arnold-chiari In A Fetal Rat Model Of Dysraphism.

Dysraphism is a defect in neural tube development, leading to dysplastic growth of the spinal cord and meninges. Myelomeningocele (MM) is just one of its forms. Hydrocephalus is among the most important alterations in MM and occurs as a consequence of Arnold-Chiari malformation (AC). Experimental models have been developed in sheep, rabbits and rats to study MM physiopathology, allowing a more detailed evaluation of clinical parameters involved in this anomaly. Using the experimental model of dysraphism in fetal rats, the aim of this study was to evaluate the relevance of AC malformations, clinical parameters and grade of histological lesions. Three groups with 16 fetuses in each were compared, MM, Control and Sham, after intrauterine surgical creation of MM on day 18.5 of gestation (term = 22 days). AC was evaluated by photographic comparison of sagittal cuts of fetal heads. Clinical and histological evaluations were also made. 88% of AC (14/16) in MM fetuses were obtained, besides 100% of clinical alterations. Necrosis and erosion of the spinal cord exposed to amniotic fluid were verified in histology. The presence of AC in the dysraphism rat model was high. These results allowed the use of this model to study alterations and intrauterine evolution of MM in a fashion similar to those observed in humans.20437-4