Yonghua Wang

Islet-derived stem cells from adult rats participate in the repair of islet damage

This study investigated the role of adult islet-derived stem cells in repairing islet damage. Using intraperitoneal injection of cerulein, a rat model of acute pancreatitis was induced in an experimental group. The expression of the protein c-kit, a pancreatic stem cell marker, was observed using immunohistochemistry at set intervals following successful model preparation. Pathological changes in pancreatic tissues were also observed using routine hematoxylin and eosin staining. Cells with positive c-kit staining were rarely observed in normal tissues. At all observation intervals after the induction of acute pancreatitis, c-kit staining was restricted to the islets. Over the course of observations, staining changed from low to high intensity, and then back to low intensity again. The primary pathological manifestation in the experimental group was edematous pancreatic tissues with local necrotic lesions. These findings suggested that c-kit positive cells are likely to be a type of pancreatic progenitor cell that is involved only in the self-repair of islet damage and does not migrate.

Therapeutic effect and mechanism of electroacupuncture at Zusanli on plasticity of interstitial cells of Cajal: a study of rat ileum

BackgroundElectroacupuncture (EA) is one of the techniques of acupuncture and is believed to be an effective alternative and complementary treatment in many disorders. The aims of this study were to investigate the effects and mechanisms of EA at acupoint Zusanli (ST36) on the plasticity of interstitial cells of Cajal (ICCs) in partial bowel obstruction.MethodsA Sprague Dawley rat model of partial bowel obstruction was established and EA was conducted at Zusanli (ST36) and Yinglingquan (SP9) in test and control groups, respectively. Experiments were performed to study the effects and mechanisms of EA at Zusanli on intestinal myoelectric activity, distribution and alteration of ICCs, expression of inflammatory mediators, and c-Kit expression.Results1) EA at Zusanli somewhat improved slow wave amplitude and frequency in the partial obstruction rats. 2) EA at Zusanli significantly stimulated the recovery of ICC networks and numbers. 3) the pro-inflammatory mediator TNF-α and NO activity were significantly reduced after EA at Zusanli, However, no significant changes were observed in the anti-inflammatory mediator IL-10 activity. 4) EA at Zusanli re-expressed c-Kit protein. However, EA at the control acupoint, SP9, significantly improved slow wave frequency and amplitude, but had no effect on ICC or inflammatory mediators.ConclusionsWe concluded that EA at Zusanli might have a therapeutic effect on ICC plasticity, and that this effect might be mediated via a decrease in pro-inflammatory mediators and through the c-Kit signaling pathway, but that the relationship between EA at different acupoints and myoelectric activity needs further study.

The naïve effector cells of collagen type I during acute experimental pancreatitis are acinar cells and not pancreatic stellate cells

OBJECTIVE The purpose of this study was to investigate the expression of collagen type I and the mRNA level of its regulatory factor, TGF-β1, in tissue samples of acute pancreatitis and to determine the significance of collagen type I in predisposition to pancreatic fibrosis during acute pancreatitis. METHODS Sprague-Dawley rats were divided into an experimental group (30 rats) and a control group (12 rats). The rats in the experimental group were intraperitoneally injected with cerulein to induce acute pancreatitis. The distribution and expression of collagen type I in the pancreatic tissues were examined by immunohistochemical staining. The mRNA level of TGF-β1 was determined by real-time polymerase chain reaction (PCR). RESULTS (1) Collagen type I was localized in the cytoplasm of pancreatic acinar cells. With pancreatitis progressed, strong positive staining for collagen type I covered whole pancreatic lobules, whereas, the islet tissue, interlobular area, and pancreatic necrotic area were negative for collagen type I. (2) The level of TGF-β1 mRNA in rats from the experimental group increased gradually the establishment of acute pancreatitis, and was significantly higher than that in the control group at every time point. CONCLUSIONS (1) During acute pancreatitis, pancreatic acinar cells, not pancreatic stellate cells as traditionally believed, were the naïve effector cells of collagen type I. (2) TGF-β1 played a key role in regulating collagen I expression during acute pancreatitis.

Learning curve for hand-assisted laparoscopic D2 radical gastrectomy.

AIM To describe the learning curves of hand-assisted laparoscopic D2 radical gastrectomy (HALG) for the treatment of gastric cancer. METHODS The HALG surgical procedure consists of three stages: surgery under direct vision via the port for hand assistance, hand-assisted laparoscopic surgery, and gastrointestinal tract reconstruction. According to the order of the date of surgery, patients were divided into 6 groups (A-F) with 20 cases in each group. All surgeries were performed by the same group of surgeons. We performed a comprehensive and in-depth retrospective comparative analysis of the clinical data of all patients, with the clinical data including general patient information and intraoperative and postoperative observation indicators. RESULTS There were no differences in the basic information among the patient groups (P > 0.05). The operative time of the hand-assisted surgery stage in group A was 8-10 min longer than the other groups, with the difference being statistically significant (P = 0.01). There were no differences in total operative time between the groups (P = 0.30). Postoperative intestinal function recovery time in group A was longer than that of other groups (P = 0.02). Lengths of hospital stay and surgical quality indicators (such as intraoperative blood loss, numbers of detected lymph nodes, intraoperative side injury, postoperative complications, reoperation rate, and readmission rate 30 d after surgery) were not significantly different among the groups. CONCLUSION HALG is a surgical procedure that can be easily mastered, with a learning curve closely related to the operative time of the hand-assisted laparoscopic surgery stage.

Three-Step Hand-Assisted Laparoscopic D2 Radical Gastrectomy for Chinese Obese Patients: A Highly Efficient and Feasible Surgical Approach

Three-step hand-assisted laparoscopic D2 radical gastrectomy (HALG) is a modified surgical procedure that has achieved satisfactory results for obese patients in our surgical center. To fully elucidate the advantages of this procedure, in this study, comprehensive and in-depth comparative analyses were performed to assess clinical data from obese gastric cancer patients who underwent HALG, laparoscopic-assisted D2 radical gastrectomy (LAG), and open D2 radical gastrectomy (OG) in our surgical center during a specific time period. For the 3 groups, incision length was 1.25 cm longer for the HALG group than for the LAG group but was significantly shorter for the HALG group than for the OG group (P =0.00). The rate of conversion to laparotomy , the pneumoperitoneum time and the number of recovered lymph nodes were significantly better for the HALG group than for the LAG group (P <0.05). The pain score at day 2 after surgery, intestinal function recovery time, and duration of postoperative hospital stay were not significantly different for the HALG and LAG groups ( P >0.05) but were significantly better for the HALG group than for the OG group (P <0.05). There were significantly fewer postoperative complications for the HALG group than for the LAG and OG groups (P =0.049). According to the results, the “three-step HALG method” incorporates both the thoroughness of the radical OG approach and the minimal invasiveness of the LAG approach for obese patients. Thus, the HALG approach is a relatively safe and extremely feasible surgical procedure for the treatment of these patients.

Stress-induced intestinal necrosis resulting from severe trauma of an earthquake.

AIM To investigate the possible reasons and suggest therapeutic plan of stress-induced intestinal necrosis resulting from the severe trauma. METHODS Three patients in our study were trapped inside collapsed structures for 22, 21 and 37 h, respectively. The patients underwent 3-4 operations after sustaining their injuries. Mechanical ventilation, intermittent hemodialysis and other treatments were also provided. The patients showed signs of peritoneal irritation on postoperative days 10-38. Small intestinal necrosis was confirmed by emergency laparotomy, and for each patient, part of the small bowel was removed. RESULTS Two patients who all performed 3 operations died of respiratory complications on the first and second postoperative days respectively. The third patient who performed 4 operations was discharged and made a full recovery. Three patients had the following common characteristics: (1) Multiple severe trauma events with no direct penetrating gastrointestinal injury; (2) Multiple surgeries with impaired renal function and intermittent hemodialysis treatment; (3) Progressive abdominal pain and tenderness, and peritoneal irritation was present on post-traumatic days 10-38; (4) Abdominal operations confirmed segment ulcer, necrosis of the small intestine, hyperplasia and stiffness of the intestinal wall; and (5) Pathological examinations suggested submucosal hemorrhage, necrosis, fibrosis and hyalinization of the vascular wall. Pathological examinations of all 3 patients suggested intestinal necrosis with fistulas. CONCLUSION Intestinal necrosis is strongly associated with stress from trauma and post-traumatic complications; timely exploratory laparotomy maybe an effective method for preventing and treating stress-induced intestinal necrosis.