RESUMO
BACKGROUND: The study of the tentorial notch can improve the understanding of brain injury mechanisms. Tentorial morphology has been analysed primarily in cadaveric studies. However, the postmortem effect can cause variability in the measurements. The objective was to evaluate the morphometry of the tentorial notch and the third cranial nerve on living subjects using magnetic resonance imaging (MRI). MATERIALS AND METHODS: A retrospective cross-sectional study was performed. Using consecutive cases, 60 MRI scans were analysed for tentorial notch morphology. Maximum notch width (MNW), notch length (NL), interpedunculoclival (IC) distance, apicotectal (AT) distance, third cranial nerve (CN-III) distance, and inter- CN-III angle, were obtained. For the classification of the tentorial notch quartile distribution technique for MNW, NL, AT distance, and IC distance were used. RESULTS: According to the quartile of the MNW, patients were stratified into narrow, midrange, and wide groups. Using the NL quartile groups, they were also classified as short, midrange, and long. With these, the tentorial notch could be classified into eight types. Statistical differences between genders in the MNW and inter-CN-III angle were found, as well as a strong positive correlation between NL and AT distance, and between right and left CN-III distances. CONCLUSIONS: There were differences between the cadaveric samples and living subjects in the CN-III distances. This difference could be explained by the dehydration of brain volume in the postmortem process which may cause nerve elongation. Morphometry of the tentorial notch and its neurovascular relations allows a better understanding of the mechanisms of brain herniation.
Assuntos
Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Estudos Retrospectivos , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , CadáverRESUMO
Epigallo-catechin-3-gallate (EGCG), found in the leaves of Camellia sinensis (green tea), has antioxidant- and scavenger-functions and acts neuroprotectively. It has been publicized as anti-aging remedy but data on potential cellular mechanisms are scarce. Recent studies claimed that EGCG specifically promotes neural precursor cell proliferation in the dentate gyrus of C57Bl/6 mice, without changes at the level of immature and mature new neurons. We here analyzed the effects of EGCG on adult hippocampal neurogenesis in male Balb/C mice and saw a different pattern. Two weeks of treatment with EGCG (0, 0.625, 1.25, 2.5, 5 and 10mg/kg) showed a dose-response curve that peaked at 2.5mg/kg of EGCG with significantly increased cell survival without affecting cell proliferation but decreasing apoptotic cells. Also, EGCG increased the population of doublecortin-(DCX)-expressing cells that comprises the late intermediate progenitor cells (type-2b and -3) as well as immature neurons. After EGCG treatment, the young DCX-positive neurons showed more elaborated dendritic trees. EGCG also significantly increased net neurogenesis in the adult hippocampus and increased the hippocampal levels of phospho-Akt. Ex vivo, EGCG exerted a direct effect on survival and neuronal differentiation of adult hippocampal precursor cells, which was absent, when PI3K, a protein upstream of Akt, was blocked. Our results thus support a pro-survival and a pro-neurogenic role of EGCG. In the context of the conflicting published results, however, potential genetic modifiers must be assumed. These might help to explain the overall variability of study results with EGCG. Our data do indicate, however, that natural compounds such as EGCG can in principle modulate brain plasticity.
Assuntos
Catequina/análogos & derivados , Sobrevivência Celular/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Catequina/química , Catequina/farmacologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Hipocampo/fisiologia , Masculino , Camundongos Endogâmicos BALB C , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Neurônios/fisiologia , Neuropeptídeos/metabolismo , Fármacos Neuroprotetores/química , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Chá/químicaRESUMO
The potential use of anodised zirconium as permanent implant has been investigated. Zirconium was anodised at constant potential between 3 and 30 V in H(3)PO(4). Electrochemical assays were conducted in simulated body fluid solution (SBF) in order to evaluate the effect of the surface oxide on the corrosion resistance in vitro after 30 days of immersion. The rupture potential increases when increasing thickness of the anodic surface film. The increase in the barrier effect when increasing anodising potential is also verified by EIS. Anodisation in H(3)PO(4) proved to increase the apatite formation capability of zirconium in a single step. In vivo bone formation was also analysed by implanting the modified materials in Wistar rats. Anodised Zr presents higher corrosion resistance in SBF in all the studied immersion times when compared with non anodised Zr. Additionally, in vivo experiments evidence bone generation and growth in contact with zirconium implants both in the as-received and anodised condition.
Assuntos
Eletrodos , Próteses e Implantes , Zircônio/química , Animais , Técnicas Eletroquímicas , Técnicas In Vitro , Ratos , Ratos Wistar , Propriedades de SuperfícieRESUMO
Objetivo: Evaluar las características de los recién nacidos de madres adolescentes del municipio Bayamo, durante su estadía en el Servicio de Neonatología. Método: Se realizó un estudio de cohorte prospectiva, tomando los recién nacidos de madres adolescentes ocurridos durante un período de 6 meses, comparándolos con una cohorte similar de madres no adolescentes, a los cuales se les llenó un cuestionario con las variables objeto de estudio, procesando la información mediante el programa EPIINFO versión 6.04 y presentados en HARVARD GRAPHIC, utilizando como procesador de texto el programa WORD PERFECT versión 5.01. Resultados: Se encontró un prodeminio de embarazadas adolescentes acompañadas y solteras con resultados significativos, los recién nacidos bajo peso alcanzan un índice de 12 por ciento, superior a la cohorte de comparación al igual que la morbilidad con un 31,3 por ciento en los hijos de adolescentes. Conclusiones: Existe predominio de embarazadas adolescentes en solteras y acompañadas, así como desocupadas y estudiantes, la sepsis y la malnutrición son más frecuentes en adolescentes, predominó el número de bajo peso, así como la morbilidad en los recién nacidos de madres adolescentes donde son más frecuentes las malformaciones congenitas, la asfixia y el trauma obstétrico.(AU)
Assuntos
Humanos , Feminino , Gravidez na Adolescência , Recém-Nascido de Baixo Peso , Anemia , Desnutrição Proteico-Calórica , Infecções UrináriasRESUMO
Se realiza la revisión bibliográfica de las obras completas de José Martí, en busca de los aspectos asociados con el pensamiento ético, la medicina preventiva y natural. Se analiza la relación de sus ideas filosóficas con las naturaleza y se demuestra, a partir de estas la existencia de significativos vínculos entre la filosofía de la naturaleza y la medicina preventiva y natural. Se ofrecen conclusiones y recomendaciones que declaran a Martí como un precursor de la medicina natural en Cuba y América así como se promueve el estudio y la introducción de sus ideas en el curriculum de las carreras de medicina y enfermería (AU)