Peroral endoscopic myotomy (POEM) has emerged as a rescue treatment for recurrent or persistent achalasia after failed initial management. Therefore, we aimed to investigate the efficacy and safety of POEM in achalasia patients with failed previous intervention. We searched the MEDLINE, Embase, Cochrane, and PubMed databases using the queries “achalasia,” “peroral endoscopic myotomy,” and related terms in March 2019. Data on technical and clinical success, adverse events, Eckardt score and lower esophageal sphincter (LES) pressure were collected.The pooled event rates, mean differences (MDs) and risk ratios (RR) were calculated. A total of 15 studies with 2,276 achalasia patients were included. Overall, the pooled technical success, clinical success and adverse events rate of rescue POEM were 98.0% (95% confidence interval [CI], 96.6% to 98.8%), 90.8% (95% CI, 88.8% to 92.4%) and 10.3% (95% CI, 6.6% to 15.8%), respectively. Seven studies compared the clinical outcomes of POEM between previous failed treatment and the treatment naïve patients. The RR for technical success, clinical success, and adverse events were 1.00 (95% CI, 0.98 to 1.01), 0.98 (95% CI, 0.92 to 1.04), and 1.17 (95% CI, 0.78 to 1.76), respectively. Overall, there was significant reduction in the pre- and post-Eckardt score (MD, 5.77; p<0.001) and LES pressure (MD, 18.3 mm Hg; p<0.001) for achalasia patients with failed previous intervention after POEM. POEM appears to be a safe, effective and feasible treatment for individuals who have undergone previous failed intervention. It has similar outcomes in previously treated and treatment-naïve achalasia patients.

Objective:To identify the differentially expressed proteins that caused hippocampal damage after liver ischemia-reperfusion (I/R) in rats.Methods:Eighteen clean-grade healthy juvenile male Sprague-Dawley rats, aged 2 weeks, weighing 20-30 g, were divided into 2 groups ( n=9 each) using a random number table method: sham operation group (S group) and liver I/R group (IR group). A rat model of liver I/R injury was prepared by restoring perfusion after 1 h of liver ischemia. The rats were sacrificed after being anesthetized at day 3 of reperfusion, and the hippocampal tissue was isolated and analyzed to obtain gene expression profiles. Differentially expressed genes were identified using the R software, and further protein interaction networks were constructed through Cytoscape and Kyoto Encyclopedia Genes and Genomes pathway analysis to determine the differentially expressed proteins. Quantitative real-time polymerase chain reaction and Western blot were used for validation. Results:A total of 45 differentially expressed proteins were identified by the proteomic analysis of hippocampal tissues, including 36 significantly up-regulated proteins and 9 significantly down-regulated proteins. The proteins with significant expression related to injury were identified from the PPI network complex using the CytoHubBA plug-in cystscape: Ras-related C3 botulinum toxin substrate (RAC2), HRAS, phosphatidylinositol-3-kinase inhibitor phosphatase and tensin homologue (PTEN), and N-methyl-D-aspartate ionotropic glutamate receptor 2b (GRIN2b). The results of quantitative real-time polymerase chain reaction and Western blot showed that the expression of RAC2, HRAS, PTEN, and GRIN2b in the hippocampal tissue was significantly up-regulated in IR group compared with S group ( P<0.05). The results of Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that differentially expressed proteins were significantly enriched in the expression of PD-L1 and its checkpoint pathway, long-term potentiation, and regulation of the Wnt signaling pathway in cancer. Conclusions:The mechanism by which liver I/R induces hippocampal injury may be related to the up-regulation of the expression of RAC2, HRAS, PTEN and GRIN2b in rats.