Notch signaling: a novel regulating differentiation mechanism of human umbilical cord blood-derived mesenchymal stem cells into insulin-producing cells in vitro / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) could be induced to differentiate into insulin producing cells (IPCs) in vitro, which have good application potential in the cell replacement treatment of type-1 diabetes. However, the mechanisms regulating this differentiation have remained largely unknown. Notch signaling is critical in cell differentiation. This study investigated whether Notch signaling could regulate the IPCs differentiation of human UCB-MSCs.</p><p><b>METHODS</b>Using an interfering Notch signaling protocol in vitro, we studied the role of Notch signaling in differentiation of human UCB-MSCs into IPCs. In a control group the induction took place without interfering Notch signaling.</p><p><b>RESULTS</b>Human UCB-MSCs expressed the genes of Notch receptors (Notch 1 and Notch 2) and ligands (Jagged 1 and Deltalike 1). Human UCB-MSCs with over-expressing Notch signaling in differentiation resulted in the down-regulation of insulin gene level, proinsulin protein expression, and insulin-positive cells percentage compared with the control group. These results showed that over-expressing Notch signaling inhibited IPCs differentiation. Conversely, when Notch signaling was attenuated by receptor inhibitor, the induced cells increased on average by 3.06-fold (n = 4, P < 0.001) in insulin gene level, 2.60-fold (n = 3, P < 0.02) in proinsulin protein expression, and 1.62-fold (n = 6, P < 0.001) in the rate of IPCs compared with the control group. Notch signaling inhibition significantly promoted IPCs differentiation with about 40% of human UCB-MSCs that converted to IPCs, but these IPCs were not responsive to glucose challenge very well both in vitro and in vivo. Hence, further research has to be carried out in the future.</p><p><b>CONCLUSIONS</b>Notch signaling may be an important mechanism regulating IPCs differentiation of human UCB-MSCs in vitro and Notch signaling inhibition may be an efficient way to increase the number of IPCs, which may resolve the shortage of islet of cell replacement treatment of type-1 diabetes.</p>

Clinical analysis of primary small intestinal neoplasms in 305 cases / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To summarive the experience in diagnosis and treatment of primary small intestinal neoplasm.</p><p><b>METHODS</b>The data of 305 patients with pathologically confirmed primary small intestinal tumor collected from 6 hospitals around the Songhua River during the past 33 years were analyzed retrospectively.</p><p><b>RESULTS</b>There were 42 benign and 263 malignant tumors in this series with a ratio of 1: 6.26. The 263 malignant tumors in this series consisted of 135 adenocarcinomas, 57 malignant stromal tumors, 37 malignant lymphomas, 20 carcinoids, and etc. Chronic occult bleeding, gradual of body weight loss and mild abdominal pain (three obscurities) were the common clinical features and alerting massage of intestinal tumor. Correct preoperative diagnostic rate was only 57.0% (174/305) due to difficulty in early diagnosis, which was 67.2% (92/137) in the duodenal tumors, and 51.9% (82/168) in the jejunoileal tumors. All of the 42 benign tumors were resected completely. For the 263 patients with malignant tumors, radical dissection was performed in 153, palliative resection in 34, and gut by-pass or biopsy in 76. The median survival of the patients who underwent radical resection of their malignant tumors was 92 months, which was significantly higher than that of the other groups.</p><p><b>CONCLUSION</b>Early diagnosis of primary small intestinal tumors is difficult and with a preoperative misdiagnosis rate of 43.0%. Total intestinal barium swallowing, endoscopy and superior mesenteric arteriography are three critical examinations for diagnosis and location. Early surgical resection is crucial in improving the prognosis. The primary small intestinal tumor should be resected as early as possible if no distant metastasis is detected.</p>

Analysis of clinical manifestations and surgical treatment of Crohn disease: a report of 82 cases / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To elucidate the clinical types of Crohn disease and evaluate its surgical treatment.</p><p><b>METHODS</b>Clinical data of 82 cases with Crohn disease were retrospectively analyzed from June 1972 to June 2003.</p><p><b>RESULTS</b>Among 82 cases with Crohn disease,38 cases were diagnosed before operation,and 44 cases(53.7% ) were misdiagnosed. Main clinical manifestations included abdominal pain(96.3% ),diarrhea(89.0% ) and abdominal mass(28.0% ),other clinical manifestations included fistulation,intestinal hemorrhage and extra- intestinal manifestations such as ulcerative stomatitis,mycotic stomatitis. Patients received different surgical procedures as following: partial enterectomy in 57 cases,hemicolectomy and colostomy in 4 patients,partial ileectomy and ileostomy in 2,ileocolic bypass procedure in 3 patients,partial enterectomy and colectomy and anastomosis in 3 patients because of internal fistula,repair of ileal perforation in 2,lysis of adhesion in 6,drainage of intraperitoneal abscess and ostomy in 3,radical operation in 2 due to colon cancerization. Seventy- three cases(89.0% ) were cured by operation,postoperative complications occurred in 9 patients and 2 cases died.</p><p><b>CONCLUSION</b>It is the key point to achieve successful operation that the corresponding operative modes respectively for varied types of Crohn disease should be adopted.</p>

Intractable constipation caused by adult dolichocolon / 中国普通外科杂志

Objective To summarize the diagnosis and surgical treatment for intractable constipation caused by adult dolichocolon.Methods Clinical data of 82 adult dolichocolon cases suffering from intractable constipation were analyzed retrospectively.Results Of the 82 patients,intractable constipation were found in 66 patients(80%),abdominalgia,abdominal distension in 28 patients(34%) and constipation alternatively with diarrhea in 16 patients(19%).Diagnosis was established in 74 patients by barium enema while 8 during the emergency operation.Dolichocolon was divided into 3 types as type Ⅰ in 35 cases,type Ⅱ in 19 and type Ⅲ in 28,in which there were 18 cases of total dolichocolon syndrome. Surgery performed including sigmoidectomy(32 patients),right hemicolectomy(3 patients),right hemicolon and transvers colon resection(4 patients),left side of transvers colon and splenic flexure colon resection(4 patients),descending colon and sigmoid colon resection(15 patients),transvers,descending and sigmoid colon resection(6 patients),pancolectomy with anastomosis of terminal ileum and upper rectum (18 patients).There were no severe postoperative complications such as anastomotic leakage and the recovery was uneventful in all 82 patients.The curative effect was graded as well and up in all 72 cases followed up from 3 months to 4 years,with a follow-up rate of 88%(72/82).Conclusion A history of intractable constipation and barium enema are the mainstay for the diagnosis of dolichocolon,and operation is the effective treatment for intractable constipation caused by adult dolichocolon.