1.Effects of Total Hip Arthroplasty on Proximal Femoral Bone Remodeling
Ye JING ; Linwei LV ; He GONG ; Feifei SHI
Journal of Medical Biomechanics 2022;37(1):E040-E044
Objective To analyze the influence of total hip arthroplasty (THA) on the process of proximal femoral bone remodeling by using the Wolff bone remodeling theory. Methods According to control equation of bone remodeling, the program of bone remodeling was written in Python language. Preoperative femur model and postoperative femur and prosthesis finite element models were established respectively in ABAQUS software. The process of bone reconstruction before and after THA operation was compared to analyze the effect of prosthesis implantation on mechanical properties of the femur in the middle and long term after THA operation. Results The stress in proximal femur continued to decrease after prosthesis implantation, and the stress site was transferred from the femoral head to the prosthesis, resulting in an obvious stress shielding phenomenon. Bone loss in the stress shielding area was serious. The femoral shaft cortical bone became thinner and the stress shielding was relieved. The medial side at the bottom of the prosthesis was compressed, and the stress was significantly higher than that of the lateral side, where the bone was unevenly distributed. Conclusions After THA operation, obvious stress shielding occured at proximal medial side of the femur, leading to bone loss and prosthesis loosening. The difference in stress levels on both sides at the bottom of the prosthesis resulted in an uneven bone distribution, causing the discordance between the prosthesis and the femur, as well as postoperative pain in the middle part of the thigh.
2.The comparison of fully-covered self-expandable metal stent and plastic stent on the treatment of post liver transplantation anastomotic biliary stricture
Maodong YE ; Weijie SU ; Xiaogang LI ; Yi JIE ; Weiqiang JU ; Anbin HU ; Linwei WU ; Yi MA ; Xiaofeng ZHU ; Xiaoshun HE ; Dongping WANG
Chinese Journal of Hepatobiliary Surgery 2020;26(10):767-770
Objective:To investigate the effectiveness and safety of fully-covered self-expandable metal stent (FCSEMS) with plastic stent over the treatment of post liver transplantation anastomotic biliary stricture (AS).Methods:The clinical data of AS patients after liver transplantation admitted to the First Affiliated Hospital of Sun Yat-sen University from January 2014 to April 2018 was collected for the retrospective study. According to different implanted stents, patients were divided into FCSEMS group and plastic stent group. The general information of the two groups of patients, surgical success rate, postoperative complications, the number of endoscopic retrograde cholangiopancreatography (ERCP), the number of indwelling stents and other indicators were compared and analyzed.Results:A total of 54 patients were enrolled, including 41 males and 13 females, with a median age of 48 (34-65) years. A total of 23 cases were included in the FCSEMS group and 31 cases were included in the plastic stent group. The overall technical success rate of the operation was 98.3% (176/179). In the FCSEMS group, there were 21 patients recovered and 2 patients were relieved; in the plastic stent group, 29 patients were recovered, 1 case was relieved, and 1 case failed. There were no statistically significant differences in the efficacy and complication rate between the two groups (all P>0.05). The median stent indwelling time, ERCP times, and the number of indwelling stents in the FCSEMS group were 5.9 months, 2 times, and 1, respectively, and in the plastic stent group were 9.5 months, 4 times, and 8 respectively. There were statistical differences between the two groups (all P<0.05). Conclusions:FCSEMS for treatment of AS showed less duration of stenting, numbers of stents and endoscopic treatment sessions with the similar efficacy as plastic stents. It’s indicated that it’s necessary to pay attention to the probability of stent migration and pancreatitis.
3. Progress of liver transplantation in treating hepatic epithelioid hemangioendothelioma
Haoxiang WEN ; Linwei WU ; Xiaoshun HE
Chinese Journal of Hepatobiliary Surgery 2019;25(11):875-878
Epithelioid Hemangioendotheliomais a rare, low-grade malignant vascular tumour. It’scalled hepatic epithelioid hemangioendothelioma(HEHE), when it occurs in liver. It can be metastatic and postoperative recurrence. There are few cases have been reported in the literature at home and abroad because of its rarity. The treatment of HEHE is also controversial. With the continuous improvement of surgical techniques of liver transplantation, it is increasingly applied to treat liver failure patients caused by HEHE. Our paper reviews the literature on disease characteristics of HEHE, and liver transplantation for HEHE indications, immunotherapy and prognosis, to illustrate the status and progress of liver transplantation for HEHE.
4.Application of Shear Wave Elastography in assessing liver allograft function in patients using organs from deceased citizens
Weijun OU ; Wenshuo TIAN ; Ying LU ; Weiqiang JU ; Ming HAN ; Xiaoping WANG ; Dongping WANG ; Linwei WU ; Yinghua CHEN ; Anbin HU ; Yi MA ; Guodong WANG ; Xiaofeng ZHU ; Zhiyong GUO ; Xiaoshun HE
Chinese Journal of Organ Transplantation 2017;38(6):331-336
Objective To investigate the correlation between the elastographic characteristics of liver and postoperative function of liver allografts.Methods Forty-eight cases of liver transplantation from The First Affiliated Hospital of Sun Yat-sen University were analyzed,Shear wave elastography (SWE) was performed before operation or at one week or one month post-operation.Liver function was evaluated by measuring alanine aminotransferase (ALT),aspartate transaminase (AST),total bilirubin (TBIL),γ-glutamine transferase (GGT),albumin (ALB),alkaline phosphatase (ALP),prothrombin time (PT),activated partial thromboplastin time (APTT),and international normalized ratio (INR).Early allograft dysfunction (EAD) was also analyzed with reference to SWE among liver transplant recipients.Results SWE at one week after transplantation was significantly correlated with TBIL (r=0.525 6,P<0.01),APTT (r=0.668 3,P<0.000 1),PT (r=0.593 7,P=0.000 1),INR (r=0.609 6,P<0.000 1) and prealbumin (r=-0.464 1,P<0.01).However,no significant correlation was observed between pre-operative SWE and parameters of post-operative liver function.SWE in EAD patients was higher than that of patients without EAD (17.60±1.09 kPa vs.13.38±0.99 kPa,P<0.01).The optimal cut-off value of SWE at one week post-operation was 14.85 kPa.Conclusion Postoperative SWE is significantly correlated with postoperative liver function tests and EAD,suggesting SWE is a potential test for evaluating the quality of liver allografts.
5.Ischemia-free liver transplantation (Reports of 3 cases)
Xiaoshun HE ; Zhiyong GUO ; Weiqiang JU ; Linwei WU ; Qiang ZHAO ; Dongping WANG ; Yi MA ; Lu YANG ; Maogen CHEN
Chinese Journal of Organ Transplantation 2017;38(10):577-583
Objective Ischemia reperfusion injury (IRI) is a major limiting factor of graft survival in organ transplantation.We've established a novel procedure called ischemia-free liver transplantation (IFLT) in big animal study.In this report,we aimed to investigate the feasibility and early outcomes of IFLT.Methods We have performed 3 cases of IFLT during July 23,2017 to August 9,2017.We analyzed the surgical methods,normothermic perfusion parameters,blood gas analysis,liver function tests and complications early after liver transplantation.Pathologic studies and immunohistochemical staining of donor liver biopsies were conducted before procurement,at the end of machine perfusion,as well as after re-vascularization for evaluating IRI.Results The surgical procedures of all 3 patients were successful,without stoppage of blood supply for the liver grafts throughout organ procurement,ex vivo preservation and implantation.During normothermic perfusion,the pH value was stable within the normal range and the lactate levels dropped quickly to lower than detected (<0.3 mmol/L) within 1.5-3 h.The livers continued to produce bile with the volume of 2-6 mL/h.Hematoxylin and eosin (HE) staining evaluation and TdT-mediated dUTP nick end labeling (TUNEL) assay of biopsies taken from liver tissues before procurement,at the end of machine perfusion and after re-vascularization,showed few necrostic and apoptotic hepatocytes in the liver biopsies.The immunohistochemical staining of IL-1β and vWF suggested no inflammatory cytokine release and sinusoidal endothelial cell activation.The three patients recovered smoothly without rejection,vascular and biliary complications.Conclusion IFLT is a feasible and effective procedure,which is able to overcome the major limitations of conventional procedure.The novel IFLT will become one of the mainstream transplant procedures in the future.
6.High Throughput Screening Method and Application for L-glutamate Specific Aminotransferase
Linwei HE ; Zhangmin LIU ; Yan FENG ; Li CUI
China Biotechnology 2017;37(8):59-65
Objective:The aim is to establish L-glutamate specific aminotransferase-L-glutamate dehydrogenase coupling 96-well high throughput screening method,which is applied to molecular evolution of aminotransferase WecE from E.coli.Methods:An optical assay for aminotransferase catalytic activity based on aminotransferase-glutamate dehydrogenase coupling system is established by optimization of coupling enzyme loading,signal molecule NADH concentration and coupling time.Mutants library of WecE is obtained by sitedirected saturation mutagenesis.Positive mutants can be screened out through 96-well preliminary screening and flask second screening.Results:The target transamination reaction is coupled with L-glutamate dehydrogenase indicative reaction system which consists of 0.5 U/ml enzyme loading and 0.4 mmol/L NADH.A positive mutant Y321F whose catalytic activity increases 3.4 fold compared to that of wild type is screened out in Tyr 321 saturation mutagenesis library of WecE.Conclusion:An accurate high throughput screening method with weak background interference is established.It offers feasible solution for molecular evolution of L-glutamate specific aminotransferase.
7.The manner of ICU staff towards organ donation
Ngalei TAM ; Wenfeng XIE ; Guangnan ZHAO ; Linwei WU ; Xiaoshun HE
Chinese Journal of Organ Transplantation 2016;37(10):611-613
Objective To investigate the past participation and their future intention of donation after citizen death (DCD) work of attendees.Methods A questionnaire study was carried out in the 9th Chinese ICU annual congress and local workshops taken part in difference provinces and cities from May 2015 to July 2015.A 12-multiple self choice questionnaires,collecting the demographic data of attendees and analyzing the ratio of DCD awareness and participation,their attitude towards DCD,and future recommendation of DCD development,were facilitated and immediately collected back.Results A total of 512 questionnaires were collected and 489 were available.97.75% of the attendees have been awareness of DCD and 62.37% have ever participated in DCD activity.During the whole survey,85.07% of them expressed their willingness of future DCD activities participation.The current fierce conflict between medical workers and patients was selected to the main barrier of DCD work.The enforcement of DCD population and organ donation law were most recommended to improve donation success.Conclusion It is the fifth year after DCD programme initiation and full implementation since last year.Despite the obvious raise of DCD recognition among ICU staff,there is still long way to go ahead to the era of satisfactory donation rate.The hostility between medical workers and patients is the main barrier for ICU workers for DCD promotion.
8.Model of reduced pediatric supracondylar humeral fracture with residual displacements:a finite element analysis of mechanical responses
Linwei CHEN ; Jingtao ZHAO ; Tingqu ZHENG ; Changqiang HE ; Hanqiao SUN ; Feng HUANG ; Xiaohui ZHENG ; Yanqun GAN
Chinese Journal of Tissue Engineering Research 2015;(13):2125-2132
BACKGROUND:Displacement of the distal fracture fragment is one of the most important facts that lead to cubitus varus fol owing pediatric supracondylar humeral fracture. Mainstream technique emphasized the restoration of posterior-ulnar deviation of the distal fragment. However, there is an absence of supportive evidences from biomechanical studies. OBJECTIVE:To establish models of extension-ulnar type of supracondylar humeral fracture and investigate the mechanical stability of reduced fracture with residual displacements within functional restoration standard, so as to provide mechanic evidences supporting the empirical rule of manipulative reduction-“better anterior than posterior, better radial than ulnar”. METHODS:The fresh cadaveric bone of right upper extremity from a 7-year-old child was scanned using CT. Models of supracondylar humeral fracture differing in contact area of the fracture site and displacement direction of the distal fragment were established and underwent loading tests. Stress in both anterior and posterior margin of the fracture site and Baumann angle were recorded, and data were analyzed and compared. RESULTS AND CONCLUSION:In comparison of stress in the posterior margin, the value was significantly greater in the posteromedial-displacement group than the others. Stress value in fracture with 75%contact area was significantly greater than the other three groups. In comparison of stress in the anterior margin, a significantly greater value was obtained in the posteromedial-displaced group. Stress value in fracture with 85%contact area was significantly greater. When comparing stress in posterior margin and anterior margin, the absolute increment of stress value was greater in posterior displacement group than in anterior displacement group. Baumann angle increased significantly when fragment displaced medial y. Above findings indicated that displacement direction altered the location of stress concentration. Stress augmentation was greater in posterior displacement group. Stress in related area significantly increased constantly when contact area of the fracture site reduced. Baumann changed obviously when fragment displaced medial y. The results preliminarily verify the hypothesis that displacement of the distal fragment was the main contributor to cubitus varus fol owing supracondylar humeral fracture. These findings provided certain evidences supporting the empirical rule“better anterior than posterior, better radial and ulnar”.
9.Study of the Changes on Tree Shrew Bronchial Epithelium Induced by Xuanwei Bituminous Coal Dust
CHEN XIAOBO ; HE MENG ; LI GUANGJIAN ; ZHOU YONGCHUN ; ZHAO GUANGQIANG ; LEI YUJIE ; YANG KAIYUN ; TIAN LINWEI ; HUANG YUNCHAO
Chinese Journal of Lung Cancer 2015;(8):469-474
Background and objective Lung cancer is the type of cancer with the highest incidence and mortality in numerous countries and regions. Establishing an appropriate animal model that can be used to simulate lung cancer etiology, pathogenesis, and similar processes, is urgent. We explore the feasibility of establishing a lung cancer model induced by Xuan-wei bituminous coal dust PM10 (particulate matter with diameters of 10 μm or less), which affects bronchial epithelium of tree shrews.Methods hTe neck skin of adult tree shrews is dissected, and the thyroid cartilage is fully exposed. Subsequently, the weak part at the top of the thyroid cartilage is treated with intratracheal agents by perfusion via a special infusion needle punc-ture method. Regular X-ray examination and lung tissue biopsy were performed on the sacriifced animals to observe changes in pulmonary imaging and bronchial epithelial cells atfer perfusion of Xuanwei bituminous coal dust PM 10.ResultshTe tree shrews of the experimental group (exposed to bituminous coal dust) died in a week atfer perfusion with PM10, whereas no animal died until the end of the experiment in the blank control and the solvent control groups. Sections of lung tissue biopsy of the regularly killed tree shrews were stained with hematoxylin and eosin. hTe lung tissues of tree shrews in the experimental group showed a serial changes caused by bronchial epithelial hyperplasia, such as squamous metaplasia, dysplasia, and early invasive carcinoma, whereas no signiifcant pathological changes were observed in the blank control and solvent control groups. Conclusion Endotracheal infusion of Xuanwei bituminous coal dust PM10 induces lung cancer in tree shrews. hTus, the lung cancer model was established.
10.Diallyl disulfide induces apoptosis in human leukemia K562 cells through activation of NADPH oxidase
Lan YI ; Youhua WU ; Hui TAN ; Jie HE ; Linwei LI ; Jian SHAN ; Qi SU
Chinese Pharmacological Bulletin 2014;(8):1107-1112
Aim Toresearchthemolecularmecha-nisms of DADS-induced apoptosis in human leukemia K562cells.Methods Cellviabilitywasmeasuredby MTT. Levels of DADS-induced ROS were measured by 2ˊ, 7ˊ-dichlorofluorescein diacetate ( DCFH-DA) fluo-rescence. DADS-induced mRNA levels of components of the NADPH oxidase were detected by Real-time PCR. The combination of protein Rac2 and p67phox was measured by immunoprecipitation assays. Flow cy-tometry methods were used to determine the percentage of apoptosis cells. DADS-induced Rac2 levels were measuredbyWesternblot.Results TheDADS-trea-ted K562 cells showed a dose-and time-dependent de-crease in cell viability and proliferation. There was sig-nificant up-regulation of the mRNA level of components of the NADPH oxidase complex in K562 cells after treatment with 6 mg·L-1 DADS for 6 h. Western blot results revealed that, compared with the control group, there was a significant up-regulation of Rac2 protein in K562 cells treated with 5. 0 and 10. 0 mg·L-1 DADS for 24h. And Rac2 combined with p67phox in DADS-induced apoptosis in K562 cells. PMA markedly in-creased the percentage of apoptotic cells, and DPI re-duced the percentage of apoptotic cells in DADS-in-duced K562 cells. Levels of DADS-induced ROS, also showed enhancement when exposed in PMA, but there was no DADS-induced ROS production evident when exposed in DPI in DADS induced K562 cells. Conclu-sions TheseresultsindicatethatNADPHoxidaseis the main source of DADS-induced ROS production. Diallyl disulfide induces apoptosis in human leukemia K562 cells through activation of NADPH oxidase.

Result Analysis
Print
Save
E-mail