[The beginnings and evolution of a pancreatic surgeon: a technical morphological analysis in first 5 years].

Objective: To explore the development of the pancreatic surgeon technique in a high-volume center. Methods: A total of 284 cases receiving pancreatic surgery by a single surgeon from June 2015 to December 2020 were retrospectively included in this study. The clinical characteristics and perioperative medical history were extracted from the medical record system of Zhongshan Hospital,Fudan University. Among these patients,there were 140 males and 144 females with an age (M (IQR)) of 61.0 (16.8) years(range: 15 to 85 years). The "back-to-back" pancreatic- jejunal anastomosis procedure was used to anastomose the end of the pancreas stump and the jejunal wall. Thirty days after discharge,the patients were followed by outpatient follow-up or telephone interviews. The difference between categorical variables was analyzed by the Chi-square test or the CMH chi-square test. The statistical differences for the quantitative data were analyzed using one-way analysis of variance or Kruskal-Wallis H test and further analyzed using the LSD test or the Nemenyi test,respectively. Results: Intraoperative blood loss in pancreaticoduodenectomy between 2015 and 2020 were 300,100(100),100(100),100(0),100(200) and 150 (200) ml,respectively. Intraoperative blood loss in distal pancreatectomy was 250 (375),100 (50),50 (65), 50 (80),50 (50),and 50 (100) ml,respectively. Intraoperative blood loss did not show statistical differences in the same operative procedure between each year. The operative time for pancreaticoduodenectomy was respectively 4.5,5.0(2.0),5.5(0.8),5.0(1.3),5.0(3.3) and 5.0(1.0) hours in each year from 2015 to 2020,no statistical differences were found between each group. The operating time of the distal pancreatectomy was 3.8 (0.9),3.0 (1.5),3.0 (1.8),2.0 (1.1),2.0 (1.5) and 3.0(2.0) hours in each year,the operating time was obviously shorter in 2018 compared to 2015 (P=0.026) and 2020 (P=0.041). The median hospital stay in 2020 for distal pancreatectomy was 3 days shorter than that in 2019. The overall incidence of postoperative pancreatic fistula gradually decreased,with a incident rate of 50.0%,36.8%,31.0%,25.9%,21.1% and 14.8% in each year. During this period,in a total of 3,6,4,2,0 and 20 cases received laparoscopic operations in each year. The incidence of clinically relevant pancreatic fistula (grade B and C) gradually decreased,the incident rates were 0,4.8%,7.1%,3.4%,4.3% and 1.4%,respectively. Two cases had postoperative abdominal bleeding and received unscheduled reoperation. The overall rate of unscheduled reoperation was 0.7%. A patient died within 30 days after the operation and the overall perioperative mortality was 0.4%. Conclusion: The surgical training of a high-volume center can ensure a high starting point in the initial stage and steady progress of pancreatic surgeons,to ensure the safety of pancreatic surgery.

[Clinical characteristics of 272 437 patients with different histopathological subtypes of primary esophageal malignant tumors].

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ2 test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.

Functionalized M2TiC2Tx MXenes (M = Cr and Mo; T = F, O, and OH) as high performance electrode materials for sodium ion batteries.

First-principles calculations were performed to study the electrochemical performance of M2TiC2 (M = Cr or Mo) and M2TiC2Tx (T = O, F or OH) used as anode materials for sodium ion batteries (SIBs). The O functionalized MXenes (Cr2TiC2O2 and Mo2TiC2O2) are found to be more stable than F and OH terminated systems. The diffusion performance of sodium in MXene materials is mainly affected by the functional groups. The lowest diffusion barrier of functionalized MXenes is about one order larger in magnitude than that of bare MXenes. Although the introduction of O-groups hinders the diffusion of sodium, it can greatly improve the theoretical storage capacities. Meanwhile, the diffusion paths and diffusion energy barriers of Na are affected by Na concentration effects, while the interactions between terminations have little effect. Furthermore, multiple layers of sodium atoms are found to be adsorbed between the layers of M2TiC2O2, thus significantly increasing the theoretical capacities. The theoretical sodium storage capacities of M2TiC2O2 monolayers reach 515.70 mA h g-1 (M = Cr) and 362.46 mA h g-1 (M = Mo) and the OCVs can approach 0.034 V (M = Cr) and 0.042 V (M = Mo). Therefore, Cr2TiC2O2 and Mo2TiC2O2 are expected to be promising anode materials for SIBs due to their excellent properties, such as good electronic conductivity, low sodium diffusion barrier, and high theoretical sodium storage capacity.

Highly flexible and efficient top-emitting organic light-emitting devices with ultrasmooth Ag anode.

We demonstrate highly flexible and efficient top-emitting organic light-emitting devices (TOLEDs) by using an ultrasmooth Ag anode. A template-stripping process has been employed to create the ultrasmooth Ag anode on a photopolymer substrate. The flexible TOLEDs obtained by this method keep good electroluminescence properties under a small bending radius and after repeated bending. The efficiency of the flexible TOLEDs is improved by 60% compared with the conventional TOLEDs deposited on Si substrate due to the enhanced hole injection from the ultrasmooth anode.