OES diagnostic of radicals in 33MHz radio-frequency Ar/C_2H_5OH atmospheric pressure plasma jet

Ar/C_2H_5OH plasma jet is generated at atmospheric pressure by 33 MHz radio-frequency power source. This RF excitation frequencies which are higher than 13.56 MHz had rarely been used in atmospheric pressure plasma. The plasma characteristics of ethanol are investigated. The introduction of ethanol leads to the generation of four excited carbonaceous species C, CN, CH and C_2 in plasma, respectively. Optical emission intensities of four carbonaceous species were strengthened with ethanol content increasing in the range of 0-4600 ppm. The ethanol content increase results in all the Ar spectra lines decrease. The reason is that the electron temperature decreases when ethanol content is high. The emission intensity ratios of C/C_2, CN/C_2 and CH/C_2 decrease with the increase of ethanol content, showing that the relative amount of C_2 is increasing by increasing the ethanol flow. The emission intensity ratios of excited species did not change much with the increase of RF power in stable discharge mode.

内镜逆行胰胆管造影术后急性胆管炎的危险因素研究及其列线图的构建

目的探讨内镜逆行胰胆管造影术(endoscopic retrograde cholangiopancreatography,ERCP)后急性胆管炎的危险因素及其列线图的构建。方法回顾性分析2014年1月—2019年12月在兰州大学第一医院因胆总管结石接受ERCP的患者临床资料,纳入术后发生急性胆管炎的患者95例(胆管炎组),以1∶3比例通过软件随机抽样选择术后未发生急性胆管炎的患者285例(无胆管炎组)。采用Logistic回归模型分析影响ERCP术后急性胆管炎的独立危险因素,根据多因素分析结果,建立预测ERCP术后急性胆管炎发生率的列线图模型。结果单因素比较发现ERCP术后发生胆管炎患者和未发生胆管炎患者在年龄、合并糖尿病、丙氨酸转氨酶、碱性磷酸酶、葡萄糖、胆囊壁粗糙、胆管直径、胆管下端狭窄、行经内镜胆道内支架放置术比例、行经内镜鼻胆管引流术比例方面差异均有统计学意义(P<0.05)。Logistic多因素回归分析显示,高龄(OR=1.108,95%CI:1.079~1.138,P<0.001)、合并糖尿病(OR=4.524,95%CI:1.299~15.758,P=0.018)、胆囊壁粗糙(OR=2.495,95%CI:1.106~5.630,P=0.028)、胆管直径增加(OR=1.303,95%CI:1.181~1.437,P<0.001)、胆管下端狭窄(OR=4.192,95%CI:2.508~7.005,P<0.001)为ERCP术后急性胆管炎的独立危险因素。根据多因素分析结果建立的列线图,受试者工作特征曲线的曲线下面积为0.887。结论高龄、糖尿病病史、胆囊壁粗糙、胆管直径增加和胆管下端狭窄为ERCP术后急性胆管炎的独立危险因素,临床医师可依据上述危险因素建立的列线图进行临床干预,改善患者预后。

Glutamine synthetase-negative hepatocellular carcinoma has better prognosis and response to sorafenib treatment after hepatectomy

Background:Glutamine synthetase(GS)and arginase 1(Arg1)are widely used pathological markers that discriminate hepatocellular carcinoma(HCC)from intrahepatic cholangiocarcinoma;however,their clinical significance in HCC remains unclear.Methods:We retrospectively analyzed 431 HCC patients:251 received hepatectomy alone,and the other 180 received sorafenib as adjuvant treatment after hepatectomy.Expression of GS and Arg1 in tumor specimens was evaluated using immunostaining.mRNA sequencing and immunostaining to detect progenitor markers(cytokeratin 19[CK19]and epithelial cell adhesion molecule[EpCAM])and mutant TP53 were also conducted.Results:Up to 72.4%(312/431)of HCC tumors were GS positive(GS+).Of the patients receiving hepatectomy alone,GS negative(GS-)patients had significantly better overall survival(OS)and recurrence-free survival(RFS)than GS+patients;negative expression of Arg1,which is exclusively expressed in GS-hepatocytes in the healthy liver,had a negative effect on prognosis.Of the patients with a high risk of recurrence who received additional sorafenib treatment,GS-patients tended to have better RFS than GS+patients,regardless of the expression status of Arg1.GS+HCC tumors exhibit many features of the established proliferation molecular stratification subtype,including poor differentiation,high alpha-fetoprotein levels,increased progenitor tumor cells,TP53 mutation,and upregulation of multiple tumor-related signaling pathways.Conclusions:GS-HCC patients have a better prognosis and are more likely to benefit from sorafenib treatment after hepatectomy.Immunostaining of GS may provide a simple and applicable approach for HCC molecular stratification to predict prognosis and guide targeted therapy.

Development of a Novel Endovascular Brachytherapy Stent:A Proof-of-concept Study

Background and Aims:Endovascular implantation of iodine-125(125I)seeds strand combined with stent is an effective method of treatment for portal vein tumor thrombosis.The aim of this study was to develop a novel endovascular brachytherapy stent(EVB-Stent)and to evaluate its feasibility of use.Methods:An EVB-Stent was implanted into the main portal vein(MPV)in a live porcine model via the percutaneous transhepatic route.Blood samples were collected and tested before and after operation,as well as before euthanasia.Single-photon emission computed tomography(SPECT)combined with CT(SPECT/CT)scan were performed directly after operation and CT scan was performed 2 months after implantation.After the CT scan was performed,all animals were euthanized and histologically examined.Results:The novel stent was successfully positioned in all six pigs.No deterioration of liver function was observed during the 2-month follow-up period.SPECT/CT revealed the uniform distribution of radiation around the seeds strand,and the hottest spot was near the center of the MPV.The patency of the stented MPV was confirmed using CT scans.The tissue-accumulated absorbed dose was 31,822.11 mGy at 10 mm transversely away from the midpoint of the 125I seeds strand,with a half-life of 59.4 days.Pathological examination results showed no significant atrophy or inflammation of adjunct liver tissue,and no obvious intima thickening or thrombosis were detected in the stented MPV.Conclusions:A liver porcine model was used to demonstrate that the transhepatic placement of a novel endovascular brachytherapy stent,EVB-Stent,is both technically feasible and safe.