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Marinesco bodies (MBs) are spherical nuclear inclusions found in pigmented neurons of the substantia nigra. Although MBs are abundant in senescent brains, how they are related to aging processes remains unclear. Here, we performed a morphometric analysis of midbrain pigmented neurons to identify the possible influence of MBs on nuclear size. The transected area of the nucleus (nuclear area) was larger in the presence of MBs and was correlated with the area of MB (MB area) in all tested brains. The MB-associated nuclear enlargement was significant even after MB areas were subtracted from nuclear areas. Moreover, higher MB immunoreactivity of p62 was detected in the nucleoplasm of the enlarged MB-associated nuclei. This study on human brains is the first quantitative approach demonstrating MB-associated nuclear enlargement and progressive accumulation of small nucleoplasmic materials. Although cellular hypertrophy is usually considered to be an indication of the upregulation of cellular function, this might not always be the case. These findings suggest that an age-related decline of ubiquitin-proteasome and autophagy system activity and stagnation of undegradable materials are one of the candidate mechanisms to explain the age-related decline of neural activity in the substantia nigra.  相似文献   
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Abstract

This study aimed to characterize the effect of different running modes on serum irisin concentrations in rats. A total of 18, 10-week-old rats were divided into three groups; control group, 16° uphill running group (concentric exercise; CON) and, ?16° downhill running group (eccentric exercise; ECC). The running group’s rats ran on the inclined treadmill at 16?m/min, for a total of 90?min. Blood was drawn from the rats, 48?h after running, after which the rats were anesthetized. The serum concentrations of irisin were measured using enzyme-linked immunosorbent assays. Vastus intermedius was collected for immunohistochemical analysis. After multiple comparisons, the ECC showed a significantly high serum irisin concentration (ECC: 28.42?±?6.31?ng/ml, CON: 21.27?±?3.03?ng/ml) and a larger irisin antibody reactive cross-sectional area in vastus intermedius compared to the CON (p?<?0.05). This is the first study to reveal that single bout downhill running increases serum irisin concentrations in rats.  相似文献   
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Reconstruction of complex knee defects including the popliteal artery presents a challenging problem in reconstructive microsurgery. Reconstruction of the popliteal artery and soft‐tissue coverage should be performed simultaneously for limb salvage. We present the one‐stage reconstruction of a complex knee defect including the popliteal artery using a free flow‐through anterolateral thigh (ALT) flap as a bypass flap in two patients with sarcomas. In both patients, the popliteal artery and vein were reconstructed using branches of the lateral circumflex femoral arterial system. The flaps survived without vascular compromise and the limbs were preserved successfully. Free flow‐through ALT flap enables simultaneous leg revascularization and soft‐tissue coverage with a single free flap. The lateral circumflex femoral arterial system has many branches with large diameters, making it suitable for reconstruction of multiple infrapopliteal arteries. © 2015 Wiley Periodicals, Inc. Microsurgery 35:485–488, 2015.  相似文献   
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