Objective: To construct the extracellular region of PCP-2(PCP-2EC) and the immunoglobin IgG Fc fusi on protein expression vector,and then express and purify the soluble PCP-2EC/Fc fusion protein for the study of its function in neuronal adhesion. Methods: PCP-2 extracellular region was amplified and cloned into an expression vector pIGplus containing human IgG Fc; PCP-2EC/Fc fusion protein was expressed by COS-7 and 293 cells transfected by the constructed plasmid and purified by protein A. The purified fusion protein was used as substrate to study its function in neuronal adhesion. Results: PCP2 extracellular region was cloned into IgG Fc expression vector successfully; PCP 2EC/Fc fusion protein was expressed and purified in mammal cells; and the purified fusion protein promoted neuronal adhesion. Conclusion:PCP 2EC/Fc fusion protein expression system is successfully constructed and the purified fusion protein can promote neuronal adhesion. These results lay a foundation for the research on the PCP-2 function in neuronal adhesion and the further functional study in the nervous system and other fields.

Objective: To construct the extracellular region of PCP-2(PCP-2EC) and the immunoglobin IgG Fc fusi on protein expression vector,and then express and purify the soluble PCP-2EC/Fc fusion protein for the study of its function in neuronal adhesion.Methods: PCP-2 extracellular region was amplified and cloned into an expression vector pIGplus containing human IgG Fc; PCP-2EC/Fc fusion protein was expressed by COS-7 and 293 cells transfected by the constructed plasmid and purified by protein A.The purified fusion protein was used as substrate to study its function in neuronal adhesion.Results:PCP-2 extracellular region was cloned into IgG Fc expression vector successfully; PCP-2EC/Fc fusion protein was expressed and purified in mammal cells; and the purified fusion protein promoted neuronal adhesion.Conclusion:PCP-2EC/Fc fusion protein expression system is successfully constructed and the purified fusion protein can promote neuronal adhesion.These results lay a foundation for the research on the PCP-2 function in neuronal adhesion and the further functional study in the nervous system and other fields.

So far， there are still no specific treatment methods for severe hepatitis and liver failure， resulting in a mortality rate of over 70%， and they are the difficulties in the treatment of critical illness in China and globally. Liver transplantation is currently the most effective treatment method for end-stage liver disease， but only 1%‍ ‍—‍ ‍2% of patients can receive the opportunity for organ transplantation. The bioartificial liver support system utilizes external mechanical， physical， and biological devices to remove various harmful substances accumulated in the patient’s body， compensate for the metabolic functions of the liver， supplement necessary substances， improve internal environment， promote the recovery of liver function， help patients get through the critical period， and save time for liver transplantation， and therefore， it is considered one of the important methods for the treatment of end-stage liver disease. Since hepatocytes are the core element of bioartificial liver， this article summarizes the sources of liver seed cells， 3D culture methods， and corresponding bioreactor culture systems and hopes to gradually solve the core issue of large-scale in vitro preparation of hepatocytes to obtain hepatocytes with adequate quantity and quality， which urgently needs to be addressed in clinical application.

Objective To investigate the risk factors of perioperative complications of laparoscopic radical distal gastrectomy and influence of body shape on the short-term therapeutic effects.Methods The retrospective case-control study was conducted.The clinicopathological data of 506 patients (328 males and 178 females,average age 60 years with the range of 24-85 years) who underwent laparoscopic radical distal gastrectomy+D2 lymph nodes dissection in the 8 clinical centers between March 2016 and November 2018 were collected,including 143 in the First Affiliated Hospital of Xiamen University,66 in the Affiliated Hospital of Qinghai University,66 in the Second Affiliated Hospital of Wenzhou Medical University,64 in the Zhongshan Hospital of Xiamen University,54 in the Affiliated Hangzhou First people's Hospital of Zhejiang University School of Medicine,48 in the Zhangzhou Affiliated Hospital of Fujian Medical University,35 in the Affiliated Quanzhou First Hospital of Fujian Medical University,30 in the Second Affiliated Hospital of Xiamen Medical College.The maximum thickness of subcutaneous fat at the level of umbilicus (USCF),the maximum vertical distance between the anterior abdominal skin and the back skin at the level of the umbilicus (UAPD),the maximum horizontal distance between the anterior abdominal skin and the back skin at the level of the umbilicus (UTD),the maximum verticaldistance between the anterior abdominal skin and the back skin at the level of the xiphoid bone (XAPD),the maximum horizontal distance between the.anterior abdominal skin and the back skin at the level of the xiphoid bone (XTD),the distance between the anterior abdominal skin and the root of celiac artery (CAD) and the maximum horizontal distance at a right angle to CAD (CATD) were measured using preoperative imaging examinations.Observation indicators:(1) intraoperative and postoperative situations;(2) follow-up situations;(3) risk factors analysis of perioperative complications;(4) influence of body shape related indexes on intraoperative situations and postoperative recovery:① Pearson univariate correlation analysis,② liner regression model analysis.Followup using outpatient examination and telephone interview was performed to detect the postoperative survival and tumor recurrence or metastasis up to December 2018.Measurement data with normal distribution were represented as Mean±SD.Measurement data with skewed distribution were described as M (range).Comparisons of count data were analyzed using the chi-square test.Comparisons of ordinal data were analyzed by Mann-Whitney U nonparametric test.Risk factors of perioperative complications of laparoscopic distal gastrectomy were analyzed by Logistic regression model.Influence of body shape related indexes on intraoperative situations and postoperative recovery was analyzed by Pearson univariate correlation analysis and liner regression model.Results (1) Intraoperative and postoperative situations:all the 506 patients underwent successful laparoscopic distal gastrectomy,including 103 with Billroth Ⅰ anastomosis,140 with Billroth Ⅱ anastomosis,201 with Billroth Ⅱ + Braun anastomosis,62 with Roux-en-Y anastomosis.The operation time,volume of intraoperative blood loss,number of lymph nodes dissected,time to postoperative anal exsufflation,time for initial fluid diet intake,time for initial semi-fluid diet intake and duration of postoperative hospital stay were (233±44)minutes,(102±86)mL,34±13,(3.6±1.5)days,(5.8±3.3)days,(8.3±3.8)days,(12.2±5.7)days respectively in the 506 patients.Of 506 patients,196 were defined as pathological stage Ⅰ,122 were defined as pathological stage Ⅱ and 188 were defined as pathological stage Ⅲ postoperatively.Of 506 patients,93 had 106 times of perioperative complications,including 33 times of pulmonary and upper respiratory infection,12 times of incisional infection,11 times of anastomotic leakage,11 times of abdominal infection,8 times of intestinal obstruction,8 times of gastroplegia,6 times of abdominal hemorrhage,5 times of bacteremia,3 times of anastomotic hemorrhage,3 times of lymph fluid leakage,2 times of pancreatic leakage,1 time of urinary infection,1 time of anatomotic stenosis,1 time of deep venous thrombosis and 1 time of pulmonary embolism;the same patient can merge multiple complications.Eleven patients were in the Clavien-Dindo classification ≥ Ⅲ.(2) Follow-up situations:465 of 506 patients were followed up for 1-32 months with a median time of 12 months.During the follow-up,451 had postoperative survival and 38 had tumor recurrence or metastasis.(3) Risk factors analysis of perioperative complications.① Results of univariate analysis showed that age,body mass index (BMI),preoperative hemoglobin,preoperative serum albumin and XAPD were related factors affecting perioperative complications of laparoscopic distal gastrectomy (x2 =10.289,7.427,5.269,5.481,4.285,P＜ 0.05).② Results of multivariate analysis showed that age,BMI,preoperative serum albumin were independent related factors affecting perioperative complications of laparoscopic distal gastrectomy (odds ratio =1.033,1.118,0.937,95％ interval confidence:1.011-1.057,1.025-1.219,0.887-0.990,P＜0.05).(4) Influence of body shape related indexes on intraoperative situations and postoperative recovery.① Results of Pearson univariate correlation analysis showed correlations between UAPD,XAPD,CAD,CATD and volume of intraoperative blood loss (r=0.107,0.169,0.179,0.106,P＜0.05),between UAPD,XAPD,CAD and the number of lymph nodes dissected (r=-0.137,-0.143,-0.173,P＜0.05),between USCF,XAPD and time to postoperative anal exsufflation (r =0.122,0.109,P＜0.05),between USCF,XAPD,CAD and time for initial fluid diet intake (r=0.132,0.108,0.132,P＜0.05),between USCF,XAPD and duration of postoperative hospital stay (r=0.116,0.100,P＜0.05).② Results of liner regression model analysis showed a positive correlation between CAD and volume of intraoperative blood loss (r =6.776),a negative correlation between CAD and the number of lymph nodes dissected (r =-0.841),with statistically significant differences (t =2.410,-1.992,P＜ 0.05);a positive correlation between USCF and time to postoperative anal exsufflation (r=0.170),between USCF and time for initial fluid diet intake (r=0.365),between USCF and duration of postoperative hospital stay (r=0.636) respectively,with statisticallysignificant differences (t =2.188,1.981,2.107,P＜ 0.05).Conclusions Abdominal shape can influence intraoperative situations and postoperative recovery of laparoscopic distal gastrectomy,but cannot increase risks ofperioperative complications.Age,BMI and preoperative serum albumin are independent related factors affecting perioperative complications of laparoscopic distal gastrectomy.

【Objective】 To investigate the effect of adequate amount of tranexamic acid(TXA)before operation on blood loss and safety in posterior lumbar fusion with multiple segments. 【Methods】 A retrospective analysis was conducted on 105 patients with lumbar spinal stenosis, submitted to our hospital for multilevel PLIF, from March 2017 to December 2019. According to the intervention method, they were divided into control group, group A and group B (n =30, 39 and 36, respectively). TXA was not used in the control group. Dripping of saline solution(100 mL) containing TXA 2g and 1g was given in Group A and Group B, and extra intravenous pumping of TXA [10 mg/(kg·h)] during surgery was conducted in Group B besides the pre-operation dripping of TXA. Total blood loss, dominant blood loss, recessive blood loss, intraoperative blood loss, postoperative drainage volume, transfusion rate and hemoglobin (Hb), hematocrit (Hct), prothrombin time international standardized ratio (PT - INR), platelet count (Plt), D - dimer (D - D), C-reactive protein (CRP), neutrophil percentage (NP), alanine aminotransferase (ALT), and blood urea nitrogen (BUN) before and after operation were compared in the three groups. Postoperative drug-related adverse events were traced. 【Results】 1)The total blood loss, dominant blood loss(mL), intraoperative blood loss(mL), drainage volume(mL) within and after 24h after surgery, and the transfusion rate(%) in group A and B were 892.6±193.5 vs 887.7±320.8, 409.1±109.2 vs, 408.6±98.3, 193.7±69.3 vs 189.6±65.6, 130.5±53.4 vs 128.3±53.5, 63.1±17.6 vs 60.9±13.5 and 7.7 (3/39) vs 8.3 (3/36), respectively, which were significantly lower than that in group C as 1 296.8±329.2, 807.6±231.5, 270.9±65.5, 365.4±127.8, 172.3±66.4 and 36.7(11/30), respectively (P< 0.05). There were no significant differences in the above indexes between group A and group B (P < 0.05). The differences in recessive blood loss was not significant by groups(P<0.05). 2) Compared with pre-operation, the levels of Hb, Hct and Plt in the three groups at 3d after operation decreased: Hb(g/L) 91.5±14.0, 107.6±16.4 and 105.9±17.1; Hct(%) 25.6±3.1, 31.2±3.9 and 30.5±4.4; Plt(×10⁹/L)146.6±31.8, 172.8 ±40.1 and 169.7±39.5(P < 0.05); while D-D, CRP and NP increased: D-D(mmol/L)365.6±67.1, 280.9±50.5 and 286.1±53.1; CRP(mg/L): 65.4±22.0, 53.4±19.6 and 56.8±17.7; NP(%): 87.3±15.6, 73.1±13.7, and 71.9±11.8(P < 0.05), and Pt-INR, ALT and BUN showed no significant changes (P > 0.05). The changes of Hb, Hct, Plt, D-D, CRP and NP in group A and B were significantly lower than those in group C at 3 days after operation [Hb (g/L) : 107.6±16.4, 105.9±17.1, 91.5±14.0; Hct (%) : 31.2±3.9, 30.5±4.4, 25.6±3.1; Plt (×10⁹/L) : 172.8 ±40.1, 169.7±39.5, 146.6±31.8; D-D (mmol/L) : 280.9±50.5, 286.1±53.1, 365.6±67.1; CRP (mg/L) : 53.4±19.6, 56.8±17.7, 65.4±22.0; NP (%) : 73.1±13.7, 71.9±11.8, 87.3±15.6] (P < 0.05), and no significant differences in the above index were noticed between group A and B(P> 0.05).3)No lower limb deep vein thrombosis nor pulmonary embolism were found in group A and group B after operation, and all the incisions were healed in the first stage, and no serious complications such as drug allergy, cardiovascular and cerebrovascular accident, epidural hematoma, epilepsy occurred. 【Conclusion】 The preoperative TXA administration with sufficient single dose showed equivalent hemostatic effect in comparison with intraoperative continuous administration additional to preoperative dripping, which is simple and convenient and does not increase the risk of thrombosis.