Ren Lang

Establishment of an Animal Model of Biliary Ischemic Stenosis With Clamping in Mice

OBJECTIVE The objective of this study was to explore a method to establish biliary ischemic stenosis in mice. METHODS After the optimal time of biliary ischemia was determined, 20 Kunming mice were equally divided into 2 groups. In the experimental group a 0.4-cm length of common bile duct was clamped for 90 minutes with 2 micro-vessel clamps (width = 0.1 cm). The common bile duct was not clamped in the control group. Twenty-one days later, biliary tract visualization was performed in all mice. Blood samples were collected from the inferior vena cava to determine the serum levels of total bilirubin (TBIL) and alanine aminotransferase (ALT). Meanwhile, samples of the common bile duct and liver tissue were extracted for microscopic examination to observe morphological changes. RESULTS In the experimental group, obvious dilatation of the common bile duct appeared over the clamp site. There was no dilatation of the common bile duct in the control group. Twenty-one days later, serum levels of TBIL and ALT were significantly higher among the experimental compared with the control group. Microscopic examination showed that the part of common bile duct at the clamp site was significantly expanded, with a smaller or occluded bile duct lumen necrotic mucosa with determination, and tubular wall with fibrosis and excrustation. A few dead liver cells and many inflammatory cells were observed in liver tissue samples. CONCLUSIONS A biliary ischemic stenosis model was established using a clamping method in mice, which may provide a reliable technique for basic and clinical research into mechanisms of biliary ischemic stenosis after liver transplantation.

Segmental portal/superior mesenteric vein resection and reconstruction with the iliac vein after pancreatoduodenectomy

Objective The results of segmental venous resection (VR) combined with pancreatoduodenectomy (PD) are controversial but may be promising. Few studies have described reconstruction of the portal/superior mesenteric vein (PV/SMV) with the iliac vein harvested from donation after cardiac death (DCD). Methods From January 2014 to April 2016, PD combined with segmental excision of the PV/SMV (VR group) was performed in 21 patients with adenocarcinoma of the head of the pancreas (ADHP). The authors established a new technique of venous reconstruction using the iliac vein from DCD and analysed patients’ long-term survival. Results The tumour dimensions and tumour staging were greater and the operation time was longer in the VR than PD group; however, no differences in the resection degree, blood loss, complications, reoperation rate, or mortality rate were found. The median survival was similar between the VR and PD groups. The long-term patency of the donor iliac vein was 90%. The degree of resection was a strong predictor of long-term survival. Conclusion Segmental PV/SMV resection combined with PD is applicable to selective patients with venous invasion by ADHP if R0 resection has probably been achieved. An iliac vein obtained by DCD provides an effective graft for venous reconstruction.

Proposed Chaoyang vascular classification for superior mesenteric-portal vein invasion, resection, and reconstruction in patients with pancreatic head cancer during pancreaticoduodenectomy – A retrospective cohort study

BACKGROUND Patients with pancreatic head cancer involving the superior mesenteric-portal vein can benefit from vascular resection and reconstruction. We aimed to propose our vascular classification and assess its effect in this study. MATERIAL AND METHODS Data of consecutive patients, who were diagnosed with pancreatic head cancer, and underwent radical pancreaticoduodenectomy combined with superior mesenteric-portal vein resection and reconstruction at our institute between October 2013 and August 2016, were retrospectively collected. On a scale of one to four, our classification was proposed. Perioperative parameters were then analyzed among the four types. RESULTS There were a total of 52 patients with 11 in type Ⅰ, 15 in type Ⅱ, 18 in type Ⅲ, 8 in type Ⅳ. The respective operative time and estimated blood loss of types Ⅲ (425-990 min, 265-1820 mL) and Ⅳ (480-1036 min, 330-1690 mL) were greater than those of types Ⅰ (300-824 min, 200-1255 mL) and Ⅱ (369-875 min, 305-1400 mL) (p < 0.05). Type Ⅳ had larger tumors (4-7 cm) than type Ⅰ (1.5-4 cm) (p < 0.05). Percentage of tunica intima involvement and the median survival time of type Ⅰ (9.1%, 22 months) were lower and longer than those of types Ⅱ (46.7%, 17 months) and Ⅲ (44.4%, 16 months; p < 0.05), and even lower and longer than those of type Ⅳ (87.5%, 10 months; p < 0.01), respectively. CONCLUSIONS Our classification can provide a system to grade patients with venous invasion in order of surgical difficulty and survival.

Integrating MicroRNA Expression Profiling Studies to Systematically Evaluate the Diagnostic Value of MicroRNAs in Pancreatic Cancer and Validate Their Prognostic Significance with the Cancer Genome Atlas Data

Background/Aims: MicroRNAs (miRNAs) are promising biomarkers for pancreatic cancer (PaCa). However, systemic and unified evaluations of the diagnostic value of miRNAs are lacking. Therefore, we performed a systematic evaluation based on miRNA expression profiling studies. Methods: We obtained miRNA expression profiling studies from Gene Expression Omnibus (GEO) and ArrayExpress (AE) databases and calculated the pooled sensitivity, specificity, and summary area under a receiver operating characteristic (ROC) curve for every miRNA. According to the area under the curve (AUC), we identified the miRNAs with diagnostic potentiality and validated their prognostic role in The Cancer Genome Atlas (TCGA) data. Gene Ontology (GO) annotations and pathway enrichments of the target genes of the miRNAs were evaluated using bioinformatics tools. Results: Ten miRNA expression profiling studies including 958 patients were used in this diagnostic meta-analysis. A total of 693 miRNAs were measured in more than 9 studies. The top 50 miRNAs with high predictive values for PaCa were identified. Among them, miR-130b had the best predictive value for PaCa (pooled sensitivity: 0.73 [95% confidence intervals (CI) 0.44-0.91], specificity: 0.81 [95% CI 0.59–0.93], and AUC: 0.84 [95% CI 0.73–0.95]). We identified nine miRNAs (miR-23a, miR-30a, miR-125a, miR-129-1, miR-181b-1, miR-203, miR-221, miR-222, and miR-1301) associated with overall survival in PaCa patients by combining our results with TCGA data. The results of a Cox model revealed that two miRNAs (miR-30a [hazard ratio (HR)=2.43, 95% CI 1.05-5.59; p=0.037] and miR-203 [HR=3.14, 95% CI 1.28-7.71; p=0.012]) were independent risk factors for prognosis in PaCa patients. In total, 405 target genes of the nine miRNAs were enriched with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and cancer-associated pathways such as Ras signaling pathways, phospholipase D signaling pathway, and AMP-activated protein kinase (AMPK) signaling pathway were revealed among the top 20 enriched pathways. There were significant negative correlations between miR-181b-1 and miR-125a expression levels and the methylation status of their promoter region. Conclusion: Our study performed a systematic evaluation of the diagnostic value of miRNAs based on miRNA expression profiling studies. We identified that miR-23a, miR-30a, miR-125a, miR-129-1, miR-181b-1, miR-203, miR-221, miR-222, and miR-1301 had moderate diagnostic value for PaCa and predicted overall survival in PaCa patients.

Treatment and outcome of intestinal perforation after liver transplant surgery in adults: a single-center experience

Objective Intestinal perforation is a rare complication after liver transplantation. This study was designed to calculate the incidence and investigate the outcomes of intestinal perforation in adult liver transplant patients. Materials and methods The clinical records of liver transplant recipients between January 2014 and June 2016 were obtained. The incidence of intestinal perforation was calculated, and high risk factors were analyzed. Results The mean operative time was 8.5 h (range: 6–11 h). The mean portal vein occlusion time was 66.5 min (range: 58–72 min), and the mean cold ischemia time was 7.9 h (range: 6.5–9.5 h). Four (2.7%) patients developed intestinal perforation from 9 to 14 days postliver transplant. All perforations were single and repaired by interrupted silk sutures. Two patients uneventfully recovered, but intestinal perforation recurred in two other patients. Simple repair was undertaken in one patient, and terminal ileum resection and ileostomy were performed in the other patient. There were no perioperative deaths. Conclusion The incidence of intestinal perforation after liver transplantation is low. Prompt diagnosis and treatment should be carried out to reduce comorbidities and mortality.