Helicobacter pylori induces epithelial-mesenchymal transition in gastric carcinogenesis via the AKT/GSK3β signaling pathway

Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.     

热疗对肿瘤免疫微环境中免疫细胞及免疫相关细胞因子的影响

随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。     

Recipient hypertonic saline infusion prevents cardiac allograft dysfunction

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

UPLC-MS/MS测定73例患者血中头孢哌酮与舒巴坦的浓度

目的：建立液相色谱-串联质谱法（UPLC-MS/MS）同时测定人血浆中头孢哌酮与舒巴坦的浓度，分析头孢哌酮/舒巴坦血药浓度监测结果，为临床合理用药提供参考。方法：以氯唑沙宗为内标，采用Waters BEHC₁₈柱（2.1 mm×100 mm，1.7 μm）进行分离，通过串联质谱仪，负离子检测模式下，以多反应监测（MRM）方式进行定量测定。对某院2018年以不同给药方案进行治疗的73例住院患者测定的头孢哌酮/舒巴坦血药浓度结果进行分析。结果：头孢哌酮与舒巴坦在测定条件下1~200 mg·L^-1范围内线性关系良好，两者日内精密度RSD均<10%，基质效应分别为（72.77±0.99）%与（75.72±0.11）%，提取回收率均>90%。73例患者共监测血药浓度96次，其中不同给药方案2 g，q8 h（43例次）；2 g，q12 h（26例次）；2 g，q6 h（27例次），各组头孢哌酮血药浓度的中位数分别为34.12 mg·L^-1（4.12~177.79 mg·L^-1）、31.23 mg·L^-1（1.89~251.8 mg·L^-1）、59.96 mg·L^-1（1.77~140.58 mg·L^-1），舒巴坦血药浓度的中位数分别为6.3 mg·L^-1（0.61~136.01 mg·L^-1）、28.83 mg·L^-1（0.5~133.69 mg·L^-1）、11.17 mg·L^-1（0.73~143.53 mg·L^-1）。Mann-Whitney U检验显示，头孢哌酮血药浓度结果无统计学差异（P>0.05），舒巴坦有统计学差异（P<0.05）。结论：本检测方法操作简便、快速、重复性好，可满足临床头孢哌酮与舒巴坦浓度的检测；头孢哌酮/舒巴坦在不同给药方案下血药浓度结果与个体差异相关，有必要开展血药浓度监测并依据结果适时调整用药方案，提高治疗效果减少耐药率的发生。     

Investigation of non-linear Mate1-mediated efflux of trimethoprim in the mouse kidney as the mechanism underlying drug-drug interactions between trimethoprim and organic cations in the kidney

The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with K_i values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with K_m values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CL_R) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CL_R (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CL_R of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates.     

A Reminder of Methylene Blue's Effectiveness in Treating Vasoplegic Syndrome after On-Pump Cardiac Surgery

The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery.