Vascular reconstruction provides short-term and long-term survival benefits for patients with hilar cholangiocarcinoma:A retrospective,multicenter study

Background:In patients with hilar cholangiocarcinoma(HCCA),radical resection can be achieved by resection and reconstruction of the vasculature.However,whether vascular reconstruction(VR)improves long-term and short-term prognosis has not been demonstrated comprehensively.Methods:This was a retrospective multicenter study of patients who received surgery for HCCA with or without VR.Variables associated with overall survival(OS)and recurrence-free survival(RFS)were identified based on Cox regression.Kaplan-Meier curves were used to explore the impact of VR.Restricted mean survival time(RMST)was used for comparisons of short-term survival between the groups.Patients’intraoperative and postoperative characteristics were compared.Results:Totally 447 patients were enrolled.We divided these patients into 3 groups:VR with radical resections(n=84);non-VR radical resections(n=309)and non-radical resection(we pooled VRnonradical and non-VR nonradical together,n=54).Cox regression revealed that carbohydrate antigen 242(CA242),vascular invasion,lymph node metastasis and poor differentiation were independent risk factors for OS and RFS.There was no significant difference of RMST between the VR and non-VR radical groups within 12 months after surgery(10.18 vs.10.76 mon,P=0.179),although the 5-year OS(P<0.001)and RFS(P<0.001)were worse in the VR radical group.The incidences of most complications were not significantly different,but those of bile leakage(P<0.001)and postoperative infection(P=0.009)were higher in the VR radical group than in the non-VR radical group.Additionally,the levels of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)up to 7 days after surgery tended to decrease in all groups.There was no significant difference in the incidence of postoperative liver failure between the VR and non-VR radical groups.Conclusions:Radical resection can be achieved with VR to improve the survival rate without worsening short-term survival compared with resection with non-VR.After adequate assessment of the patient’s general condition,VR can be considered in the resection.

3例16p11.2微缺失综合征胎儿的产前诊断及其产前超声分析

目的分析3例16p11.2微缺失综合征胎儿的临床资料,探讨其产前诊断方法及宫内表型。方法回顾3例产前诊断为16p11.2微缺失(593 kb)胎儿的染色体核型分析、单核苷酸多态性微阵列(SNP微阵列)检测结果,分析这3例胎儿的产前超声特点。结果病例1和病例2胎儿羊水染色体核型为46,XX,病例3胎儿羊水染色体核型为46,XY。病例1的SNP微阵列结果为arr[hg19]16p11.2(29,428,531~30,350,748)X1,即16p11.2存在922 kb的缺失。病例2的SNP微阵列结果为arr[hg19]16p11.2(29,591,326~30,176,508)X1,即16p11.2存在585 kb的缺失。病例3的SNP微阵列结果为arr[hg19]16p11.2(29,428,531~30,176,508)X1,即16p11.2存在748 kb的缺失。3例均有关键区域缺失,包含PRRT2、KCTD13、TBX6、HIRIP3、SEZ6L2等候选致病基因。病例1、2产前超声均提示胎儿半椎体畸形、脊柱侧弯,病例3产前超声提示胎儿颈部半透明膜增厚。结论 16p11.2微缺失综合征在产前可出现各个系统超声异常,但椎体畸形最为常见。中国汉族人群产前超声中如果出现胎儿半椎体畸形、脊柱侧弯,应考虑16p11.2微缺失综合征的可能。SNP微阵列分析可以有效地诊断16p11.2微缺失综合征,明确其断裂点以及所涉及的基因,有助于分析其基因型与表型的对应关系。

Ex vivo liver resection followed by autotransplantation in radical resection of gastric cancer liver metastases:A case report

BACKGROUND Radical resection of gastric cancer liver metastases(GCLM)can increase the 5-year survival rate of GCLM patients.However,patients may lose the theoretical feasibility of surgery due to the critical location of liver metastasis in some cases.CASE SUMMARY A 29-year-old woman had a chief complaint of chronic abdominal pain for 1 year.Abdominal computed tomography and magnetic resonance imaging examinations suggested a mass of unknown pathological nature located between the first and second hila and the margin of the lower segment of the right lobe of the liver.The anterior wall of the gastric antrum was unevenly thickened.The diagnosis of(gastric antrum)intramucosal well-differentiated adenocarcinoma was histopathologically confirmed by puncture biopsy with gastroscopy guidance.She underwent radical resection(excision of both gastric tumors and ex vivo liver resection followed by autotransplantation simultaneously)followed by XELOX adjuvant chemotherapy.Without serious postoperative complications,the patient was successfully discharged on the 20th day after the operation.Pathological examination of the excised specimen indicated that gastrectomy with D2 lymph node dissection for primary gastric tumors and R0 resection for liver metastases were achieved.The resected mass was confirmed to be poorly differentiated gastric carcinoma(hepatoid adenocarcinoma with neuroendocrine differentiation)with liver metastases in segments VIII.No recurrence or metastasis within the liver was found during a 7.5-year follow-up review that began 1 mo after surgery.CONCLUSION Application of ex vivo liver resection followed by autotransplantation in radical resection for GCLM can help selected patients with intrahepatic metastases located in complex sites obtain a favorable clinical outcome.

Relieving segregation in twin-roll cast Mg-8Al-2Sn-1Zn alloys via controlled rolling

Twin-roll casting(TRC)of Mg alloys with high Al content has unique advantages and broad development prospects.However,the severe segregation of high-alloyed Mg caused by TRC technology is difficult to solve at present,which restricts its practical application.In this work,the homogenization of coarse segregated phases in a twin-roll cast Mg-8Al-2Sn-1Zn(ATZ821)alloy was successfully achieved by a method combining solid-solution heat treatment and controlled rolling,which is suitable for industrial-scale production.In addition,the evolution of the microstructure was studied in detail.It was found that phases dynamically precipitated and dissolved repeatedly during the hot rolling process,and the evolution of entire second phases can be classified into three stages,i.e.,the net dissolution,balancing and net precipitation stages.During the process,the large-size chain-like eutectic phases evolved into a fine and nearly spherical(∼0.4μm)morphology that was uniformly dispersed in the Mg-matrix due to the thermodynamic coupling and the Ostwald ripening effect.Moreover,a fine grain microstructure(∼4μm)was obtained.The formidable segregation problem of twin-roll cast Mg alloys with high Al content was solved,which is an important finding for the industrial application of high-alloyed twin-roll cast sheets.©2020 Published by Elsevier B.V.on behalf of Chongqing University.

Assessment of traumatic brain injury degree in animal model

Objective:To establish stable and controllable brain injury with accurate degree and good repeatability in rat model.Methods:Controlled cortical impact(CCI) device was used to prepare for the rat brain injury model by the impact head of different model(Group A No.4.Group B No.5,Group C No.6) and the impact depth(Group A:1.5-2.0 mm.Group B:2.5-3.0 mm.Group C:3.5-4.0mm) with impact time of 0.1 s and impact velocity of 2.5 m/s.Twelve rats with three months of age were used in each group(the impact depth of every two rats was added 1 mm respectively).After modeling for 1 h,magnetic resonance imaging(MRI) was received and brain histopathology was observed to assess degree of injury by model parameter's of three groups.Results:After modeling of Group A,MRI showed that the cortex structure was damaged with a small amount of bleeding in center and mild edema around,and the total volume of injury was(28.69±4.94)mm^3.Pathology revealed the injury was confined to the superficial cortical with mild edema of nerve cell,which was assessed as mild cerebral contusion.While after modeling,MRI of Group B showed that the structure of cortex and medulla were damaged simultaneously and extended to cerebral nuclei zone,With 4 cases of hematoma in the center and larger edema range around,and the total volume of injury was(78.38±9.28) mm^3.Pathology revealed the injury range was reached nuclei zone,with swell of nerve cell and mitochondria,which was assessed to moderate cerebral contusion.After modeling of Group C,MRI showed that extensive tissue injury was appeared in cortex and medulla and deep nuclei,with 9 cases of hematoma and large edema signal of surrounding tissue T2W1,while in 5 cases,lateral nucleus of injury signal was increased,and the total volume of injury was(135.89±24.80)mm^3.Pathology revealed the deep cerebral nuclei was damaged,with the disappearance of neuronal structure and vacuolization of mitochondria,which was assessed as severe cerebral contusion.MRI changes were consistent with pathological changes in three groups of model,and the injury range was significantly different(P<0.01).Conclusions:Application of CCI can make stable quantitative traumatic brain injury model,which overcomes the randomness in previous injury model and possesses highly unity in iconography and pathology changes.This can provide quantitative modeling reference for clinical research.

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence

Background:The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation(LT).Gastroduodenal artery(GDA)disconnection increased proper hepatic artery flow.Whether this procedure attenuates biliary non-anastomotic stricture(NAS)is not clear.Methods:A total of 241 patients with LT were retrospectively analyzed.The patients were divided into the GDA disconnection(GDA-)and GDA preservation(GDA+)groups.Propensity score matching(PSM)was administrated to reduce bias.Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM.Postoperative complications were compared.Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival.Results:In all,99 patients(41.1%)underwent GDA disconnection,and 49(20.3%)developed NAS.Multivariate logistic regression revealed that GDA preservation(OR=2.24,95%CI:1.11-4.53;P=0.025)and model for end-stage liver disease(MELD)score>15(OR=2.14,95%CI:1.12-4.11;P=0.022)were risk factors for biliary NAS.PSM provided 66 pairs using 1:2 matching method,including 66 GDA disconnection and 99 GDA preservation patients.Multivariate logistic regression after PSM also showed that GDA preservation(OR=3.15,95%CI:1.26-7.89;P=0.014)and MELD score>15(OR=2.41,95%CI:1.08-5.36;P=0.031)were risk factors for NAS.When comparing complications between the two groups,GDA preservation was associated with a higher incidence of biliary NAS before and after PSM(P=0.031 and 0.017,respectively).In contrast,other complications including early allograft dysfunction(P=0.620),small-for-size graft syndrome(P=0.441),abdominal hemorrhage(P=1.000),major complications(Clavien-Dindo grade≥3,P=0.318),and overall survival(P=0.088)were not significantly different between the two groups.Conclusions:GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Gradual or Hysteretic Transition:Anion Effects on Cobalt(II)Spin Crossover Complexes

Comprehensive Summary To better understand the impact of different anions on the structures and SCO properties of the CoII SCO complexes,six new complexes[Co(terpy-CH_(2)OH)_(2)]A_(2)·sol(terpy-CH_(2)OH=4′-(hydroxymethyl)-2,2′;6′,2″-terpyridine,A=Br^(–)(1,sol=1.5H_(2)O),I^(–)(2),N_(3)^(–)(3,sol=2H_(2)O),H_(3)BCN^(–)(4),OTf^(–)(5),and TsO^(–)(6,sol=4H_(2)O·CH_(3)CN),have been synthesized and characterized.All six compounds consist of mononuclear[Co(terpy-CH_(2)OH)_(2)]^(2+)cations and charge-balancing anions that differ in size,shape,and hydrogen bonding capacity.Complexes 1,2,3,and 6 displayed incomplete gradual SCO transitions,whereas 4 and 5 exhibited abrupt hysteretic spin transitions with loops of 12 and 16 K(250.0—262.0 K for 4,and 370.0—386.0 K for 5,respectively),closely resembling our previously reported complexes with SCN^(–)and SeCN^(–)anions.The occurrence of the order-disorder transition of the CH2OH groups and their transition temperatures are determined by the size and hydrogen bonding capability of the anions.Remarkably,the transition temperatures of complexes with H_(3)BCN^(–),SCN^(–),OTf^(–),and SeCN^(–)anions exhibit an upward trend as the size and mass of the anions increase,as confirmed through detailed single crystal structure analyses conducted in both high-spin and low-spin states for all four complexes.

Low-cycle fatigue life prediction of a polycrystalline nickel-base superalloy using crystal plasticity modelling approach

A crystal plasticity model is developed to predict the cyclic plasticity during the low-cycle fatigue of GH4169 superalloy.Accumulated plastic slip and energy dissipation as fatigue indicator parameters(FIPs)are used to predict fatigue crack initiation and the fatigue life until failure.Results show that fatigue damage is most likely to initiate at triple points and grain boundaries where severe plastic slip and energy dissipation are present.The predicted fatigue life until failure is within the scatter band of factor 2 when compared with experimental data for the total strain amplitudes ranging from 0.8%to 2.4%.Microscopically,the adjacent grain arrangements and their interactions account for the stress concentration.In addition,different sets of grain orientations with the same total grain numbers of 150 were generated using the present model.Results show that different sets have significant influence on the distribution of stresses between each individual grain at the meso-scale,although little effect is found on the macroscopic length-scale.

Effect of thermal annealing on the microstructure, mechanical properties and residual stress relaxation of pure titanium after deep rolling treatment

The aim of this paper was to investigate the effect of thermal annealing on the microstructure, mechanical properties, and residual stress relaxation of deep rolled pure titanium. The microstructure and mechanical properties of the surface modified layer were analyzed by metallographic microscopy, transmission electron microscope and in-situ tensile testing. The results showed that the annealed near-surface layer with fine recrystallized grains had increased ductility but decreased strength after annealing below the recrystallization temperature, where the tensile strength was still higher than that of the substrate. After annealing at the recrystallization temperature, the recrystallized near-surface layer had smaller grain size,similar tensile strength, and higher proportional limit, comparable to those of the substrate. Moreover, the residual stress relaxation showed evidently different mechanisms at three different temperature regions:low temperature(T≤ 0.2 Tm), medium temperature(T≈(0.2–0.3) Tm), and high temperature(T≥ 0.3 Tm).Furthermore, a prediction model was proposed in terms of modification of Zener-Wert-Avrami model,which showed promise in characterizing the residual stress relaxation in commercial pure Ti during deep rolling at elevated temperature.

Microstructural Evolution, Mechanical Properties and Thermal Stability of Gradient Structured Pure Nickel

The microstructural evolution of pure nickel treated by deep rolling(DR)technique with different indent depths was investigated by means of optical microscopy and transmission electron microscopy.The surface roughness,hardness and residual stress distribution along the depth from surface were measured.Moreover,the DR-treated sample was annealed at temperatures from 300 to 700℃for 2 h.The results reveal that dislocation movements are the fundamental mechanisms of gradient grain refinement during the DR process.With increasing indent depth of the DR,the gradient microhardness on the cross section of sample significantly increases,the maximum compressive residual stress decreases,and the affecting region of residual stress increases.The results of thermal stability depict that the microstructure can be stable as temperature up to 300℃,and the abnormal grain growth and annealing twins are observed at 600℃.

Effect of Stress Ratio on the Fatigue Crack Propagation Behavior of the Nickel-based GH4169 Alloy

The fatigue crack growth behavior of the newly developed GH4169 nickel-based alloy at a maximum stress of 700 MPa and different stress ratios was investigated in the present work employing the specimens with a single micro- notch at a frequency of 129 Hz at room temperature. The results demonstrate a typical three-stage process of fatigue crack propagation processing from the microstructurally small crack （MSC） stage to the physically small crack （PSC） stage, and finally to the long crack stage. The crack growth rate in the MSC stage is relatively high, while the crack growth rate in the PSC stage is relatively low. A linear function of crack-tip reversible plastic zone size was proposed to predict the crack growth rate, indicating an adequate prediction solution.

Apolipoprotein E gene polymorphisms associated with processing speed and executive functions in healthy Han Chinese

Dear Editor,A few studies have focused on exploring APOE gene- related effects on cognitive functions and brain activities in healthy populations. Bondi et aL found that ε4 carriers perform significantly worse on the California Verbal Learning Test than non-carriers in non-demented old subjects （mean age, 72 years）ε11. But the results are not entirely consistent. For example, Scarmeas et aL found no effect of the E4 allele on neuropsychological performance[2] in young adults, and Jochemsen et al. found that the ε4 allele is associated with age-related cognitive decline[3]. Furthermore, protective and negative effects of the E2 allele on cognition are inconsistent[4＇ s]. APOE E2 is thought to be a protective allele for AD in the elderly population due to its role in the superior cognitive performance of ε2 carriers compared to E3 or E4 carriers[5]. However, the ε2 allele has also been found to have a negative effect on AD pathology[4].