Zefeng Xia

The Safety and Efficiency of Surgery with Colonic Stents in Left-Sided Malignant Colonic Obstruction: A Meta-Analysis

Objective. This meta-analysis is aimed at assessing the safety and efficiency of colonic self-expanding metallic stents (SEMS) used as a bridge to surgery in the management of left-sided malignant colonic obstruction (LMCO). Methods. A systematic search was conducted in PubMed, Web of Knowledge, OVID, Google Scholar, CNKI, and WANGFANG for relevant randomized trials comparing colonic stenting used as a bridge in semielective surgery versus emergency surgery from January 2001 to September 2013. Result. Five published studies were included in this systematic review, including 273 patients (140 male/133 female). 136 patients received semielective surgery after SEMS installation while 137 patients underwent emergency surgery without SEMS. SEMS intervention resulted in significantly lower overall colostomy rate (41.9% versus 56.2%, P = 0.02), surgical site infection rate (10.2% versus 19.7%, P = 0.03), and overall complication rate (29.2% versus 60.5%, P = 0.05). There was no statistic difference for the rate of primary anastomosis, anastomotic leak and operation-related mortality between two groups. Conclusions. semielective surgery with SEMS as a bridge for proper patients of LMCO can lower the overall rate for colostomy, surgical site infection, and complications.

Influence of Bariatric Surgery on the Expression of Nesfatin-1 in Rats with Type 2 Diabetes Mellitus

OBJECTIVE Bariatric surgery has been reported to be very effective in the remission of type 2 diabetes mellitus (T2DM). However, the mechanism is still under debate. Nesfatin-1, a recently discovered anorexigenic neuropeptide, was reported to be very important in glucose metabolism and regulating food intake. In this study, the effects of bariatric surgery on the expression and regulation of nesfatin-1 were discussed. METHODS T2DM was induced in SD rats by a diet high in sugar and fat plus a low dose of streptozotocin (STZ) (25 mg/kg) injection. Bariatric surgeries, including Roux-En-Y Gastric Bypass (RYGB) and sleeve gastrectomy (SG), were performed on these rats. Two months after the surgery, the plasma nesfatin-1 level and the expression of nesfatin-1 in different organs of the rats were tested. Next, in vivo administration of nesfatin-1 after surgery was performed to investigate the role of nesfatin-1 in bariatric surgery. RESULTS Both RYGB and SG could reduce the weight of the rats. However, only RYGB had significant effects on the blood glucose level. Neither surgeries seemed to affect the blood concentration of insulin. However, RYGB significantly improved insulin sensitivity. Expression of nesfatin-1 in the plasma and relative organs decreased in T2DM rats and rose again after RYGB; however, this pattern did not occur in SG. Injection of nesfatin-1 after SG significantly improved insulin resistance and reduced blood glucose levels. CONCLUSIONS Nesfatin-1 may improve insulin sensitivity in T2DM rats and thus plays a very important role in the remission of T2DM after RYGB. This neuropeptide could be a new target for directing future improvements in the bariatric surgical process.

Study on magnetic properties for La0.67Sr0.33MnO3 − δ/Pr0.7Ca0.3MnO3 − δ/La0.67Sr0.33MnO3 − δ trilayer epitaxial film

We studied systematically the magnetic properties of La0.67Sr0.33MnO3 − δ/Pr0.7Ca0.3MnO3 − δ/La0.67Sr0.33MnO3 − δ trilayer epitaxial film fabricated on (001) LaAlO3 single-crystal substrate using a direct current magnetron sputtering technique. A spin-glass-like behaviour and a magnetization relaxation phenomenon are observed from the results of the dependences of susceptibility on temperature (χ versus T curve) and magnetic relaxation on time (M versus t curve). The magnetic relaxation results are well fitted using the double-well-potential model. We also discussed the possible mechanism for the existence of spin-glass-like behaviour in the film. According to the χ versus T curves and the hysteresis loop, a magnetic anisotropy was observed in the film. The difference in electron-magnetic properties between La0.67Sr0.33MnO3 − δ single-layer epitaxial film and La0.67Sr0.33MnO3 − δ/Pr0.7Ca0.3MnO3 − δ/La0.67Sr0.33MnO3 − δ trilayer epitaxial film is also discussed.

IFN-γ secretion in gut of Ob/Ob mice after vertical sleeve gastrectomy and its function in weight loss mechanism

SummaryVertical sleeve gastrectomy (VSG) is becoming more and more popular among the world. Despite its dramatic efficacy, however, the mechanism of VSG remains largely undetermined. This study aimed to test interferon (IFN)-γ secretion n of mesenteric lymph nodes in obese mice (ob/ob mice), a model of VSG, and its relationship with farnesoid X receptor (FXR) expression in the liver and small intestine, and to investigate the weight loss mechanism of VSG. The wild type (WT) mice and ob/ob mice were divided into four groups: A (WT+Sham), B (WT+VSG), C (ob/ob+Sham), and D (ob/ob+VSG). Body weight values were monitored. The IFN-γ expression in mesenteric lymph nodes of ob/ob mice pre- and post-operation was detected by flow cytometry (FCM). The FXR expression in the liver and small intestine was detected by Western blotting. The mouse AML-12 liver cells were stimulated with IFN-γ at different concentrations in vitro. The changes of FXR expression were also examined. The results showed that the body weight of ob/ob mice was significantly declined from (40.6±2.7) g to (27.5±3.8) g on the 30th day after VSG (P<0.05). At the same time, VSG induced a higher level secretion of IFN-γ in mesenteric lymph nodes of ob/ob mice than that pre-operation (P<0.05). The FXR expression levels in the liver and small intestine after VSG were respectively 0.97±0.07 and 0.84±0.07 fold of GAPDH, which were significantly higher than pre-operative levels of 0.50±0.06 and 0.48±0.06 respectively (P<0.05). After the stimulation of AML-12 liver cells in vitro by different concentrations of IFN-γ (0, 10, 25, 50, 100, and 200 ng/mL), the relative FXR expression levels were 0.22±0.04, 0.31±0.04, 0.39±0.05, 0.38±0.05, 0.56±0.06, and 0.35±0.05, respectively, suggesting IFN-γ could distinctly promote the FXR expression in a dose-dependent manner in comparison to those cells without IFN-γ stimulation (P<0.05). It was concluded that VSG induces a weight loss in ob/ob mice by increasing IFN-γ secretion of mesenteric lymph nodes, which then increases the FXR expression of the liver and small intestine.Vertical sleeve gastrectomy (VSG) is becoming more and more popular among the world. Despite its dramatic efficacy, however, the mechanism of VSG remains largely undetermined. This study aimed to test interferon (IFN)-γ secretion n of mesenteric lymph nodes in obese mice (ob/ob mice), a model of VSG, and its relationship with farnesoid X receptor (FXR) expression in the liver and small intestine, and to investigate the weight loss mechanism of VSG. The wild type (WT) mice and ob/ob mice were divided into four groups: A (WT+Sham), B (WT+VSG), C (ob/ob+Sham), and D (ob/ob+VSG). Body weight values were monitored. The IFN-γ expression in mesenteric lymph nodes of ob/ob mice pre- and post-operation was detected by flow cytometry (FCM). The FXR expression in the liver and small intestine was detected by Western blotting. The mouse AML-12 liver cells were stimulated with IFN-γ at different concentrations in vitro. The changes of FXR expression were also examined. The results showed that the body weight of ob/ob mice was significantly declined from (40.6±2.7) g to (27.5±3.8) g on the 30th day after VSG (P<0.05). At the same time, VSG induced a higher level secretion of IFN-γ in mesenteric lymph nodes of ob/ob mice than that pre-operation (P<0.05). The FXR expression levels in the liver and small intestine after VSG were respectively 0.97±0.07 and 0.84±0.07 fold of GAPDH, which were significantly higher than pre-operative levels of 0.50±0.06 and 0.48±0.06 respectively (P<0.05). After the stimulation of AML-12 liver cells in vitro by different concentrations of IFN-γ (0, 10, 25, 50, 100, and 200 ng/mL), the relative FXR expression levels were 0.22±0.04, 0.31±0.04, 0.39±0.05, 0.38±0.05, 0.56±0.06, and 0.35±0.05, respectively, suggesting IFN-γ could distinctly promote the FXR expression in a dose-dependent manner in comparison to those cells without IFN-γ stimulation (P<0.05). It was concluded that VSG induces a weight loss in ob/ob mice by increasing IFN-γ secretion of mesenteric lymph nodes, which then increases the FXR expression of the liver and small intestine.

Gastric cancer in a situs inversus totalis patient with multiple intestinal and vessel variations related to gastrectomy surgery: A case report and literature review

Rationale: Situs inversus totalis (SIT) is a rare congenital anomaly characterized by complete inversion of the abdominal and thoracic organs, and often involves multiple genetic mutations. The most suitable surgical technique for patients with multiple vessel and organ variations as well as SIT remains unclear. Furthermore, there has been insufficient clinical evidence that demonstrates which surgical techniques achieve the best outcomes. Finally, the standard of care has not yet been determined. We present the case of a 60-year-old man with SIT, who was diagnosed with moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction. We further describe the advantage of using robotic-assisted laparoscopic surgery in patients with this anomaly. Patient concerns: A 60-year-old man complained of pain in his upper abdomen for 3 months. Physical examination revealed an apex beat in the right fifth intercostal space, and vascular anomalies were noted on abdominal angiographic computed tomography. Diagnoses: Moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction with SIT. Interventions: Robot-assisted total gastrectomy with D2 lymph node dissection and hand-sewn Roux-en-Y anastomosis was performed. Outcomes: The postoperative course was uneventful, and the patient was discharged on the seventh postoperative day. Lessons: Robotic surgery for gastric cancer is a safe and feasible alternative to laparoscopic surgery and it can be successfully used to treat gastric cancer in patients with SIT with multiple anatomic variations. As exemplified by our case, SIT might be accompanied by multiple anatomic variations. Detailed preoperative detailed imaging of the blood vessels and gastrointestinal tract is useful in these patients.