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BACKGROUND:Insufficient blood supply after major bone defects leads to osteocyte necrosis;therefore, the tissue-engineered bone cannot meet the clinical requirements. OBJECTIVE:To construct an artificial vessel using in vitro cultured rabbit bone marrow stromal stem cel s and human umbilical vein endothelial cel s combined with the rabbit aortic decel ularized vascular matrix. METHODS:Rabbit bone marrow stromal stem cel s were cultured by adherent method, human umbilical vein endothelial cel s were cultured in vitro and isolated, and rabbit aortic decel ularized vascular stent was prepared. The stent-cel composite was constructed, and its biocompatibility was observed under scanning electron microscope. There were three groups:blank control, control (bone marrow stromal stem cel-stent) and experimental (stent-cel composites) groups (n=10 per group), fol owed by implantation around the smal vessels. Three months later, the vascular samples were col ected for gross observation and hematoxylin-eosin staining. RESULTS AND CONCLUSION:Fibroblast-like cel clones were formed by adherent method, and were positive for CD44+and STRO-1+after climbing;calcified nodule formed in the ossification. Flow cytometry showed CD34+accounting for 43.83%, and visible VIII factor in the endothelial cel s. In the experimental group, endothelial cel s formed a single cel layer onto the scaffold under scanning electron microscope;the artificial vessel grew wel and tubular structure presented and eight angiod structures were found. Thin film-like vessels formed in the blank control group and there were only endothelial-like tissues in the control group. These results suggest that angiod structures can form after the stent-cel composite implantation, causing no immune reaction, but the artificial vessel is visible in absence of muscular layer.
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Objective To evaluate the preventive and therapeutic effects of heparin on dextron sulphate sodium (DSS)-induced colitis in mice. Methods The normal mice (n=16) which had been received DSS orally for 7 days were randomized into two groups, the preventive group with heparin subcutaneous administration, and the control group with normal saline subcutaneous administration. The DSS-induced colitis mice (n=16) were randomized into two groups, the treatment group with heparin and the control group with normal saline subcutaneous injection for 7 days. The preventive and therapeutic effects of heparin were assessed by disease activity index (DAI), histological score, TNF-? mRNA expression using hybridization in situ, and Martius scarlet blue (MSB) fibrin staining used to identify microvascular thrombi. Results Microvascular thrombi in the prevention group significantly decreased compared with those in the controls. Microvascular thrombi were positive in 4 of 8 controls, none in the prevention group (P=0.038). Histological score and TNF-? mRNA in the treatment group significantly decreased compared with those in the controls. Histological score of rectum and transverse colon, and expression of TNF-? mRNA in the treatment group and those in the controls were 1.33 and 1.85(P
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Objective Clinical values of endoscopy and histopathology in differential diagnosis of Crohn's disease(CD) and intestinal tuberculosis were evaluated by characterising the distinctive diagnostic features of CD and intestinal tuberculosis in surgically resected specimens.Methods To review retrospectively the surgical enterocolonic specimens and to compare the clinical,endoscopic and morphologic features of CD or intestinal tuberculosis.Selected histological parameters were evaluated retrospectively in both 30 cases of CD and intestinal tuberculosis.Results The sensitivity,specificity and accuracy of endoscopy in diagnosis of CD and intestinal tuberculosis were 80.0%,25.6% 49.3% and 86.7%,46.2% 63.8% respectively.The histological characteristic parameters of intestinal tuberculosis were confluent granulomas often with caseous necrosis and thinning submucosa;the features of CD were granulomas without caseous necrosis ,submucosal hyperplasia fissure like ulceration and prominent lymphoid aggregates.Some histopathology similarities of CD and intestinal tuberculosis were found,such as chronic non-specific inflammation of intestinal wall,ulceration,collections of epithelioid histocytes,microgranulomas and transmural inflammation.Conclusions Although distinctive diagnostic features of CD and intestinal tuberculosis were found in their clinical,endoscopical and pathological study.The final differential diagnosis depends largely upon pathology.
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Objective To investigate the patterns of mesorectum lymph node (LN) metastases of rectal cancer. Methods Rectal cancer specimens obtained by total mesorectum excision were treated with lymph node revealing solution to retrieve all the nodes, and examined by routine pathology and immunohistochemical staining. Results A total of 443 LN in 26 specimens were harvested, with 128 nodes(28 9%)in 23 cases (88 5%) found positive. Positive nodes with the size less than 5 mm accounted for 59%. Among the 23 metastatic cases, there were 14 cases with tumors locating in the posterior wall, 69 out of 71 positive nodes were found along the superior rectal artery. In the other 9 cases, tumors were found in the lateral wall, 29 out of 57 positive nodes were found around ipsilateral branches of superior rectal artery,7 were around the contralateral branches, 4 were around the ipsilateral branches of middle rectal artery. Conclusions Most positive LN were less than 0 5 cm in diameter. LN metastasis of rectal cancer have close relationship with tumor location. Tumors in the posterior wall tend to spread upward along the superior rectal artery, while tumors in the lateral wall may have upward and lateral LN metastases simultaneously, with most metastatic LN found ipsilaterally.