Abstract:

Abstract:Liver transplantation (LT) has become an important treatment for end stage hepatobiliary disorders. However, biliary complications following LT are common and greatly hamper the clinical efficacy. Endoscopic therapy has been the first-line modality for these biliary problems, though technically difficult and complex. We have managed more than 1 000 cases of complications following LT via endoscopic approach. Here we summarized the therapeutic methods and strategies of our center, hoping to provide evidence for better clinical practice.

Abstract:Objective To investigate the value, safety and efficacy of fully-covered self-expandable metallic stent (FCSEMS) in endoscopic retrograde cholangiopancreatography (ERCP) procedures for pancreatic-biliary diseases. Methods The clinical data of 56 patients with pancreatic-biliary diseases, who underwent FCSEMS treatment via ERCP from January 2008 to June 2012, were retrospectively analyzed. The stents of different lengths and types were chosen according to the condition of patients. The stents were removed under endoscope. The therapeutic effects at end point, stent removing rate and associated complications were observed. Results FCSEMS was placed in 49 patients with benign stricture, including post-liver transplant stricture (32), iatrogenic biliary stricture (12) and chronic pancreatitis-associated stricture (5). The mean follow time was (15±8.6) months (range 5-38 months), the mean stent duration was (8.4±5.3) months (1-15 months), and the effective rate was 89.8% (44/49). FCSEMS was placed in 7 patients with biliary complications, including bleeding after endoscopic sphincterotomy (EST) (4), perforation after EST (1), and bile leakage following liver transplantation (2). The mean follow time was (5±3.7) months (range 1-12 months), the mean stent duration was (1.8±0.5) months (1-8 months), and the effective rate was 100%. All FCSEMS were successfully retrieved. The short-term complication rate associated with stent was 8.9% (5/56), including post-ERCP pancreatitis (2), early cholangitis (2) and cholecystitis (1). The long-term complication rate was 12.5% (7/56), including stent slip (2), stent translocation (3) and stent-associated cholangitis (2). Conclusion FCSEMS can not only be used to treat traditional benign pancreatic-biliary strictures, but alto serve as a potential substitute for safe and effective treatment of serious biliary complications.

Abstract:Objective To evaluate the safety and long-term outcomes of endoscopic deployment of multiple plastic stents for treatment of biliary stricture after living donor liver transplantation (LDLT). Methods Between June 2005 and June 2012, 31 patients with biliary strictures after LDLT received endoscopic retrograde cholangiopancreatography(ERCP) and multiple plastic stents placement. The technical success rate and ERCP-related complications were observed. The patients were followed up and the duration of stents treatment, stricture eliminating rate, and sustained clinical success rate were recorded. Results The ERCP findings revealed stricture in 22 cases and stricture plus leakage in 9. The endoscopic technical success rate was 87.1% (27/31). ERCP-related complications included acute pancreatitis in 1 case, acute cholangitis 2 and partial stent migration in 2. There were no procedure-related deaths. The median period from stent deployment to removal was 9.6 months. The stricture eliminating rate was 95% (19/20) and sustained clinical success rate was 88.2% (15/17) during a follow-up of 5-43 months (median 38 months). Conclusion Endoscopic deployment of multiple plastic stents is safe and effective for biliary stricture after LDLT, with acceptable long-term outcomes, and the method may be a first-line therapy option for biliary stricture after LDLT.

Abstract:Objective To compare the safety and efficacy of simultaneous bilateral biliary metal stents with plastic stents under endoscope for treatment of malignant hilar biliary obstruction (MHBO). Methods From May 2007 to December 2011, 142 MHBO patients were selected for this study, with 32 receiving bilateral metal stent drainage and 110 receiving bilateral plastic stent drainage. The success rate of endoscopic operations, postoperative jaundice-reducing effect, post-endoscopic retrograde cholangiopancreatography (ERCP) complications, and stent patency period were observed. Results The procedures were successful in all patients in the two groups. The postoperative jaundice-reducing effect rates were 96.9%(31/32) in the metal stent group and 88.2%(97/110) in the plastic stent group (P>0.05). Two patients in the metal stent group and six in the plastic stent group had post-ERCP cholangitis, which was relieved by anti-inflammatory intervention, replacement of stents or endoscopic nasobiliary drainage. Two patients in the plastic stent group had stent slip. There were no pancreatitis, gastrointestinal bleeding, perforation or ERCP-related deaths in the two groups. Two patients in the metal stent group and 4 in the plastic stent group died, and the biliary stents were patent until they died. Eight patients in metal stent group and 29 patients in the plastic stent group developed recurrent obstructive jaundice, which were treated by reimplantation or replacement of the plastic stents. The post-ERCP complication rates were similar in the two groups (P>0.05). The median patency period of the metal stent was (248.53±138.61) d and that of the plastic stent was (101.76±38.53) d, showing significant difference by Log-rank test (P<0.001). Conclusion For Bismuth Ⅱ-type, bilateral bile duct invaded, or non-resectable MHBO patients, if biliary drainage range permits and the expected survival period >3 months, double metal stent biliary drainage has more advantages.

Abstract:Objective To evaluate the safety and clinical effectiveness of biliary drainage combined with endoscopic intraductal radiofrequency ablation (RFA) for treatment of malignant biliary obstruction. Methods Eighteen patients with malignant biliary obstruction, who were unsuitable for surgical resection, were prospectively selected for this study. During endoscopic retrograde cholangiopancreatography (ERCP), when biliary cannulation was successfully done, a bipolar radiofrequency probe was introduced into the bile duct via a guide wire. RFA was done under fluoroscopy, which was followed by stent placement. The patients were closely observed and followed up after procedure. Results All patients received successful RFA and biliary drainage. Twelve patients were implanted with plastic stents and 6 with metal stents; 3 patients were also implanted with pancreatic stents. Four patients developed mild complications (2 cholangitis and 2 pancreatitis), which were controlled by conservative therapy. Jaundice was promptly controlled in 61% (11/18) patients. The patients were followed up for a median of 10.9 months (range 2.0-15.4 months). The stent patency rates of 3 months, 6 months and 12 months were 87%(13/15), 64% (9/14) and 25% (2/8), respectively. The 6 month- and 12 month-survival rates were 67% (8/12) and 50% (4/8), respectively. Conclusion Biliary drainage combined with endoscopic intraductal RFA is technically feasible and safe for treatment of malignant biliary obstruction.

Abstract:Objective To investigate the therapeutic strategies, methods, safety and efficacy of simultaneous placement of self-expanding metallic stent (SEMS) in the bile duct and duodenum under endoscope for treatment of malignant biliary and duodenal obstruction. Methods The clinical data of patients with obstructive jaundice combined with severe duodenal stricture, who were treated with simultaneous placement of biliary SEMS and duodental SEMS under endoscope during January 2009 to June 2012, were retrospectively analyzed. The success rate of endoscopic management, complications, relief of jaundice and results of gastric outlet obstruction scoring system (GOOSS) were analyzed. Results Totally ten patients meeting the criteria were analyzed in this study. The patients included 5 cases with pancreatic cancer, 2 with gallbladder cancer, 2 with cancer of bile duct and one with duodenal papilla caner. Five patients with type Ⅰ duodenal stricture (without invading duodenal papilla) successfully received biliary stents through endoscopic retrograde cholangiopancreatography (ERCP) after placement of duodenal stents. One patient with type Ⅰ duodenal stricture was implanted with a 9 cm duodenal stent before endoscopic anterograde cholangiopancreatography (EACP), then a SEMS was implanted in the bile duct through endoscopic ultrasonography-guided biliary drainage (EUS-BD). Three patients with type Ⅱ duodenal stricture (with invading duodenal papilla) underwent EACP and biliary stent placement through EUS-BD, and then the duodenal stent was deployed in duodenum after EACP. The patient with type Ⅲ (away from the duodenal papilla) was implanted with biliary and duodenal stents. The success rate of endoscopic management was 100%. Two patients had self-controlled bleeding of intestinal mucosa, which was caused by endoscope friction when passing through the duodenal stricture, but without any continuous bleeding or perforation. Symptoms of jaundice and gastric outlet obstruction were greatly relieved after treatment. Conclusion For patients with unresectable malignant biliary obstruction combined with duodenal stricture, endoscopic placement of SEMS in the bile duct and duodenum simultaneously is a safe and effective method to palliate dual malignant obstruction via different endoscopic managements.

Abstract:Objective To study the effects of apoptosis-stimulating protein of p53-2 (ASPP2) gene on hepatocellular carcinoma (HCC) cell proliferation and apoptosis under starvation and the related mechanism. Methods Lentivirus encoding shRNA against ASPP2 was constructed to knockdown ASPP2 expression in hepatoma cell HepG2. Cell proliferation and apoptosis were observed by transmission electron microscopy, MTS analysis, flow cytometry analysis and morphologic changes. The influence of silencing ASPP2 gene on the proliferation and apoptosis under amino acid-starvation and serum-deprivation culture was observed; autophagy inhibitor 3-methyladenine (3-MA) was added in the experiment so as to detect the involvement of autophagy in the changes induced by ASPP2 down-regulation.Results Transmission electron microscopy showed cytoplasmic accumulation of autophagosomes when ASPP2 was knocked down under amino acid-starvation and serum-deprivation (P<0.05), with increased GFP-LC3 dots (P<0.05). MTS analysis showed that silence of ASPP2 gene greatly enhanced the proliferation of HepG2 cells (P<0.05), which could be inhibited by addition of 3-MA (P<0.05). Microscope observation showed that silence of ASPP2 gene promoted the anti-apoptotic ability of HepG2 cells, which was reversed by treatment with 3-MA. Early sign of apoptosis was observed in shASPP2+3-MA group.Annexin Ⅴ-PI double staining showed that ASPP2 silence decreased the apoptotic rate of HepG2 cells from (38±5)% to (15±4)% (P<0.05), and 3-MA treatment increased it to (36±3)% (P<0.05). Conclusion Down-regulation of ASPP2 expression may facilitate the survival and proliferation of HCC cells through activating autophagy under starvation.

Abstract:Objective To investigate the role of tumor necrosis factor-α (TNF-α) in epithelial-mesenchymal transition (EMT) of hepatocellular carcinoma (HCC) cells and the related mechanism. Methods HCC cell lines Hep3B and SMMC-7721 were treated with TNF-α for 24 h; then the cell morphological changes were observed by microscope and the expressions of the epithelial markers (E-cadherin and β-catenin), mesenchymal markers (Vimentin and N-cadherin), and EMT associated transcriptional factor Twist were examined by RT-PCR and Western blotting analysis. The invasion and metastasis ability was evaluated by Transwell and wound healing assay. Luciferase reporter assay and immunofluorescence were used to determine NF-κB transcriptional activity; Western blotting analysis was used to examine the expression levels of IκBα and p-IκBα protien. Cells was also incubated with TNF-α and NF-κB inhibitor (BAY11-7082) together, and then the phenotype of EMT was detected by microscope, RT-PCR and Western blotting analysis. Results Hep3B and SMMC-7721 cells had EMT phenotype after treated with TNF-α. Wound healing assay showed that the wound healing rate of cells exposed to TNF-α was significantly increased compared with the non-treated group (P<0.05), and Transwell assay showed that more cells penetrating the membrane after treatment with TNF-α (P<0.05). TNF-α effectively promoted IκBα phosphorylation and the subsequent NF-κB nuclear translocation. We also found that TNF-α-mediated EMT could be converted by NF-κB inhibitor (BAY11-7082) (P<0.05). Conclusion TNF-α induces EMT of HCC cells through NF-κB-dependent pathways, and subsequently promotes the invasion and metastasis of HCC.

Abstract:Objective To screen and analyze the serum microRNA (miRNA) profile of moyamoya disease (MMD), so as to elucidate the possible pathogenesis of the disease. Methods MiRNA microarray was used to test the serum of 10 MMD patients and 10 healthy controls to identify the miRNA profile. Some angiogenesis-associated miRNAs were validated by RT-PCR. TargetScan software was used for prediction and the differential miRNAs were obtained. Furthermore, the key signal pathways and miRNAs involved in MMD pathogenesis were analyzed by gene ontology and pathway analysis. Results A genome-wide miRNA array revealed 50 up-regulated and 44 down-regulated miRNAs in the sera of MMD patients; several important miRNA families and clusters were detected. RT-PCR assay confirmed that miRNA-106b, miRNA-130a and miRNA-126 were significantly up-regulated and miRNA-125a-3p was significantly down-regulated in the serum of MMD patients, suggesting the high reliability of miRNA array. Pathway analysis showed that the most enriched pathway was mTOR signaling pathway, with 16 potential functional targets. Conclusion We have identified the serum miRNA signature in MMD patients, and further analysis indicates that mTOR pathway-associated miRNAs might play an important role in MMD pathogenesis.

Abstract:Objective To establish the vulnerable atherosclerotic plaque model with rabbits and treat them with intravenous infusion of bone marrow mesenchymal stem cells (MSCs) , so as to verify the impact of MSCs on the stability of vulnerable plaque (VP). Methods Totally 24 healthy male New Zealand white rabbits were randomly divided into three groups. Carotid vulnerable atherosclerotic plaque models were made with rabbits in VP group (n=8) and VP+MSCs group (n=8); VP+MSCs group was given intravenous infusion of 1×10⁷ MSCs immediately after modeling and VP group was infused with phosphate buffer. Stable atherosclerosis plaque model was made with rabbit in SP group (n=8). Animals in all groups were sacrificed at the end of the 12^th week, and the right common carotid arteries were collected and subjected to H-E staining and Masson staining, and the cap/core ratio of atherosclerotic plaque was measured. MMP-2 content was examined by immunohistochemistry. Results H-E staining. In VP group the plaque showed a large lipid core and thin fibrous cap, remnants of foam cells and many inflammatory cells were seen in the plaque shoulder, and some showed rupture plaques and/or thrombosis. In SP group, the structure of plaque was in integrity, with thick fibrous cap and fewer inflammatory cells, and with no plaque rupture. The plaque structure of VP+MSCs group was between those of the other two groups. The order of cap/core ratio was SP group >VP+MSCs group >VP group, with that of VP group being significantly different from those of the other two groups (P<0.01). Masson staining. The contents of muscle fiber and elastic fiber were the highest in SP group, followed by VP+MSCs group, and then by VP group. The level of MMP-2 in VP group was significantly higher than those in the other two groups(P<0. 01), and that in VP+MSCs group was significantly higher than that in SP group (P<0.01). Conclusion Intravenous infusion of MSCs can improve the stability of plaques in VP rabbit model, which may be associated with the reduction of inflammatory cells and MMP-2 level, and the subsequent reduction of collagen fiber degradation.

Abstract:Objective To explore the roles of histamine and tryptase in chronic pancreatitis pain development and maintenance. Methods Rat models of chronic pancreatitis were prepared, and the histamine and tryptase contents were examined in the pancreatic specimens of both model group and the control group. The pancreas incubation supernatants of both groups were injected into the plantar surface of the rat hindpaw, and then the pain thresholds were observed at 0.5, 1, 3, 5, and 7 h after injection. Rats injected with the supernatant of chronic pancreatitis model were also given H1 receptor blocker or protease inhibitor to observe their treatment for hyperalgesia. Results The histamine and tryptase contents in the pancreas specimens were increased in chronic pancreatitis model rats. Injection of supernatant from the chronic pancreatitis specimens had a profound hyperalgesia effect within 5 h after injection, and the effect could be partially reduced by H1 receptor blockers and protease inhibitors. Conclusion Our findings suggest that histamine and tryptase are important mediators in the development and maintenance of the chronic pancreatitis pain.

Abstract:Objective To investigate the effect of heat exposure during fixed time on the thoracic aorta contractile properties of rats and the related mechanism. Methods Male Wistar rats were randomly divided into control group, random-time heat exposure group and fixed-time heat exposure group (ambient temperature to 24℃；the two heat exposure groups were exposed to heat \[36℃\] 6 h daily). After 7 days of heat exposure, the body core temperature of rats was measured by telemetry technology. The response of isolated thoracic aorta to noradrenaline (NA) was determined by organ bath system. Expression of aorta eNOS mRNA and plasma NOx (NO2-and NO3-) content were also examined. Results Heat exposure showed no significant effects on body core temperature of rats (P>0.05). Compared with control group, the fixed-time heat exposure group had significantly lowered thoracic aortic vascular reactivity to NA (P<0.01). Compared with control group and random-time heat exposed group, the fixed-time heat exposure group had significantly increased eNOS mRNA expression and plasma NOx content (P<0.05).Conclusion Fixed-time exposure to heat can change the reactivity of the thoracic aorta in rats, and vascular endothelial cell-derived NOS pathway may be involved in the vasodilatory effects.

Abstract:Objective To study the expression of ubiquitin-activating enzyme E1 (UBE1) and Bcl-2 in diffuse large B cell lymphoma (DLBCL) and its clinicopathological relevance. Methods Tumor tissues were collected from 80 DLBCL patients, and tissues from 30 patients with reactive lymphoid hyperplasia (RH) were taken as controls. Immunohistochemistry detection (EnVision method) was used to detect the expressions of CD10, Bcl-6 and MUM1 in DLBCL tissues for immunology typing of GCB or ABC. The expression of UBE1 and Bcl-2 proteins in DLBCL tissues and RH tissues was assayed by immunohistochemical staining, and its correlation with patients’ clinical pathological indices were analyzed. We also analyzed the correlation of UBE1 expression with Bcl-2 expression in DLBCL tissues. Results The positive rates of UBE1 were 65.0% (52/80) in DLBCL tissues and 13.3%(4/30) in RH tissues (P<0.05). The positive rates of UBE1 were 53.3% (16/30) for GCB type DLBCL and 72.0%(36/50) for ABC type (P<0.05). The positive rates of Bcl-2 were 51.3% (41/80) in DLBCL tissues and 10.0% (3/30) in RH tissues (P<0.05). The positive rates of Bcl-2 were 36.7%(11/30) for GCB type DLBCL and 60.0% (30/50) for ABC type (P<0.05). The positive rate of UBE1 was correlated with age and the extranodal involvement site (P<0.05). The positive rate of Bcl-2 was correlated with age, Ann Arbor stage, extranodal involvement site and international prognostic index (P<0.05). UBE1 expression was positively correlated with Bcl-2 in ABC type DLBCL (r=0.582, P=0.001). Conclusion UBE1 and Bcl-2 proteins are highly expressed in ABC type DLBCL tissues, which probably plays a role in the development and progression of DLBCL. High expression of UBE1 and Bcl-2 may indicate poor prognosis of DLBCL patients.

Abstract:Objective To introduce a new method of local denervation by ablation and to observe its effect on ventricular effective refractory periods and ventricular arrhythmia susceptibility after acute myocardial infarction. Methods Eighteen mongrel dogs were used to make myocardial infarction model by ligation of the 1st diagonal artery. Then local denervation was achieved by using six radiofrequency ablations (each at 8 W for 2 min) along the left anterior descending artery. Effective refractory periods were tested at six sites on the left ventricular epicardium (above, in and below the infarction areas, 2 sites each area) before and after local denervation by S1S2 stimulation. Ventricular arrhythmia was also induced after myocardial infarction and after denervation by burst pacing, and the number of arrhythmia episodes was recorded. Results The effective refractory periods were significantly prolonged after ablation (\[191.3±24.9\] ms vs \[209.0±27.2\] ms, P/em<0.05). And the prolongation of effective refractory periods in infarcted area (\[11.3±8.8\] ms) was significantly shorter than those in the other 2 areas (\[23.2±10.2\] ms and \[18.7±11.5\] ms). After ablation, 8 of the 11 susceptible dogs were free of induced ventricular arrhythmia, while 3 of them were still inducible by burst pacing. The induced ventricular arrhythmia rate was reduced from 61.1% (11/18) to 16.7 %(3/18) (P/em=0.007). Conclusion The method in this study is promising for preventing ventricular arrhythmia in patients with acute myocardial infarction receiving percutaneous coronary intervention.