Effects of hVEGF cDNA on random skin flap via a replication-deficient adenovirus vector / 中华整形外科杂志

<p><b>OBJECTIVE</b>The purpose of this study was to determine the effects of local delivery of vascular endothelial growth factor( VEGF) transferred with adenovirus-mediated gene on the survival of ischemic random skin flap in rats.</p><p><b>METHODS</b>The animals were divided into three groups randomly (n = 10) . A 2 cm x 8 cm dorsal skin flap was designed with the pedicle at the level of the iliac crest. In group A (AdCMV-VEGF), each animal received 10(12) PR replication-deficient recombinant adenovirus (AdCMV-VEGF) in the distal two-thirds of the proposed flap by means of the subdermal injection at ten different locations. In group B (AdCMV-GaI), each received 1012 PR AdCMV-Gal. In Group C (Saline), each received 1 ml saline. Three days after the treatment, the flap was elevated as planed way and re-sutured back to its donor site. All the animals were evaluated 7 days after the operation.</p><p><b>RESULTS</b>The mean percentage of surviving flap area was (85.91 +/- 2.54)% in group A, (59.56 +/- l.18)% in group B, and (61.48 +/- l.09)% in group C. There was a significant increase in the percentage of the survival area in the flaps of the group A, compared with the group B and group C (Group B vs. Group A, P < 0.01; Group C vs.Group A, P < 0.01, Group B vs. Group C, P >0.05). Hybridization in the situ, the immunohistochemical stain showed that the VEGF was expressed in the survival tissue of the flap treated with the AdCMV-VEGF, but it was not found in the control groups. Histological analysis demonstrated qualitatively greater amount of granulation tissue and angiogenesis was found in the group treated with the AdCMV-VEGF than the controls.</p><p><b>CONCLUSIONS</b>The results may indicate that Ad vector carrying VEGF cDNA could be useful in enhancing the survival of the skin flap due to the effect of the local delivery of the VEGF.</p>

Morphological changes of the peritoneum in peritoneal dialysis patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Long-term peritoneal dialysis (PD) requires that the peritoneal membrane remain effective for dialysis. Research directed toward human peritoneal morphology and structure is limited. The present study was performed to investigate morphological changes of the human peritoneal membrane during PD and to elucidate the possible mechanisms of its functional deterioration.</p><p><b>METHODS</b>A total of 32 peritoneal biopsies were performed in normal subjects (n = 10), uremic nondialysis patients (n = 12) at the time of catheter insertion, and PD patients (n = 10) at the time of catheter removal or reinsertion or at the time of renal transplantation. Peritoneal morphology was examined by light microscopy, scanning electron microscopy, and transmission electron microscopy.</p><p><b>RESULTS</b>The peritoneal membrane in normal subjects consisted of a monolayer of mesothelial cells on a basement membrane and a layer of connective tissue containing cells, blood vessels, and lymphatic vessels. Mesothelial cells were polygonal, often elongated, and had numerous microvilli on their luminal surface. There were lots of oval or roundish pinocytotic vesicles in the cytoplasm of the mesothelial cells. The peritoneal morphology of uremic nondialysis patients was similar to that of normal subjects. However, significant abnormalities of the peritoneal membrane were observed in PD patients, and the changes were found to be progressive. Microvilli were the first site of damage which involved microvilli shortening, a gradual reduction in their number, and, eventually, the total disappearance of microvilli. Mesothelial cells then detached from the basement membrane, disappearing completely in some cases. In the end, the peritoneal membrane consisted only of submesothelial connective tissue without any cells.</p><p><b>CONCLUSIONS</b>PD can modify peritoneal morphology and structure. The morphological change is progressive and may be one of the important causes of peritoneal failure. Peritoneal biopsies can provide lots of valuable information about the effects of PD. Studying the relationship between peritoneal structure and its function proved very useful for understanding the physiopathology of the peritoneum during PD.</p>