RESUMO
Ischemic stroke is the leading cause of death and disability. Although stroke mainly affects aged individuals, animal research is mostly one on young rodents. Here, we examined the development of ischemic injury in young (9-12-week-old) and adult (72-week-old) C57BL/6 and BALB/c mice exposed to 30 min of intraluminal middle cerebral artery occlusion (MCAo). Post-ischemic reperfusion did not differ between young and adult mice. Ischemic injury assessed by infarct area and blood-brain barrier (BBB) integrity assessed by IgG extravasation analysis was smaller in adult compared with young mice. Microvascular viability and neuronal survival assessed by CD31 and NeuN immunohistochemistry were higher in adult than young mice. Tissue protection was associated with stronger activation of cell survival pathways in adult than young mice. Microglial/macrophage accumulation and activation assessed by F4/80 immunohistochemistry were more restricted in adult than young mice, and pro- and anti-inflammatory cytokine and chemokine responses were reduced by aging. By means of liquid chromatography-mass spectrometry, we identified a hitherto unknown proteome profile comprising the upregulation of glycogen degradation-related pathways and the downregulation of mitochondrial dysfunction-related pathways, which distinguished post-ischemic responses of the aged compared with the young brain. Our study suggests that aging increases the brain's resilience against ischemic injury.
Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Camundongos , Animais , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/metabolismo , Isquemia Encefálica/complicações , Isquemia Encefálica/metabolismo , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/metabolismo , Encéfalo/metabolismo , Traumatismo por Reperfusão/metabolismo , Modelos Animais de DoençasRESUMO
The aim of this study was to predict carcass tissue composition of goat kids using the decision tree with CHAID algorithm (DT) and artificial neural network (ANN) method in comparison with classical step-wise regression (SWR) analyse. Data were obtained from 57 goat kids of Gokceada breed. Predictor variables were pre-slaughter weight, several carcass measurements and indices, weights of different carcass joints and dressing percentage. R2 values ranging from 0.212 to 0.371 indicating low to moderate accuracy were obtained for predicting muscle proportion. DT and ANN yielded similar R2 values for predicting bone proportion. DT was the best prediction method for estimating proportions of subcutaneous fat (R2 = 0.828) and intermuscular fat (R2 = 0.789). According to DT analyses, cold carcass weight was the most important factor influencing bone proportion, while kidney knob and channel fat weight was the predominant factor influencing subcutaneous, intermuscular and total fat proportions. Consequently, the use of DT method can be considered to predict carcass fat proportions.