BACKGROUND:Titanium alloy, a commonly used bone biomaterial, holds good biocompatibility and proper mechanical properties, but without osteointegration ability. Surface bioactive coating of titanium alloy can overcome such problems. OBJECTIVE:To review the application progress of surface bioactive coating on titanium alloys, and to explore the mechanism underlying its osteogenic induction. METHODS:PubMed and CNKI databases were searched for literatures concerning surface bioactive coating on titanium alloys published from January 2000 to March 2016, using the keywords oftitanium, titanium alloys, coating, surface modification, bonein English and Chinese, respectively. Through preliminary analysis, 42 eligible articles were selected. RESULTS AND CONCLUSION:The surface modification method has undergone the transition from surface roughening, oxidation, acidification treatment to the most widely used biomimetic coating technology. The surface biomimetic coatings of titanium alloys mainly include hydroxyapatite, bioactive glass, zeolite, which have been developed from a single coating to the composite coatings and gradient coatings. What's more, the bioactive factor or/and metal ions in the coating can improve the osteointegration of surface coating. Surface modification for titanium alloys is a complex process, during which, both the osteogenesis ability and the bonding strength between the coating and its substrate cannot be ignored. Improving the fabrication method of existing coatings and exploring new materials of biomimetic coatings are critical to achieve a high-quality surface coating modification.

BACKGROUND:Surface modification of titanium surface to improve its biological activity is the research hotspot. Strontium-doped coating is considered to be an effective approach to promote the implant osseointegration. OBJECTIVE:To introduce the research progress of strontium-modified biomedical titanium al oys.METHODS:Articles related to the medical titanium al oys modified with strontium published from January 2000 to April 2016 were retrieved from CNKI and PubMed databases. The keywords were“titanium (Ti), strontium (Sr), bone, osteogenic”in Chinese and English, respectively. RESULTS AND CONCLUSION:Titanium al oys have been widely used in bone implantation because of their good biocompatibility and similar elasticity modulus with human bones. However, pure titanium al oys have poor bioactivity which leads to weak bone-implant contact. Surface modification is a good approach to enhance implant osseointegration. Sr-doped surface treatment can promote new bone formation and osseointegration. Most of the studies about Sr-doped modification are ongoing at the extracorporeal and animal experiment stage;therefore, further investigation is required to seek rapid, stable, available, safe and effective methods.

BACKGROUND: Porosity has been proven to improve the stability of orthopedic implants, and the architecture of pores is considered as a significant factor to improve the osseointegration of implants. OBJECTIVE: To introduce the research advance in porous architecture. METHODS: WOS database was searched for the articles addressing the porous structure of the implants published from January 2000 to April 2016 using the keywords of scaffold, pore size, porosity, osteogenesis. The literatures were screened according to the inclusion and exclusion criteria.RESULTS AND CONCLUSION: (1) The stability of traditional implants cannot meet the requirements in some specific circumstances, while the implants with porosity can improve the stability due to its osteogenesis ability. (2) Porous structure is a hotspot, and the osseointegration of porous implants in vivo is explored through series of in vitro and in vivo experiments. (3) It has been shown that higher porosity, proper pore size, microporous morphology and microstructure of the pore wall may contribute to the growth and differentiation of bone tissue under enough mechanical support. (4) However, most studies on the porous implants are still on the in vivo and animal experimental stage, and its promoting effects on the osteogenesis and bone in-growth are needed to be investigated in depth.

BACKGROUND: At present, there are investigations on the expression of cytokines and adhesion molecular in ischemia-reperfusion injury at abroad,but they do not involve in the relative studies on endogenous cytokines and adhesion molecular on microvascular endothelial surface following injury.The expression of endogenous interleukin-1(IL-1) is limited only at mRNA level.OBJECTIVE: To prove into the mechanism of the expression of intercellular adhesion molecular 1 and its regulation factor IL-1 in spinal ischemia-reperfusion injury.DESIGN: A randomized grouping design, animal experiment.SETTING: Department of Sports Medicine, College of Physical Education Affiliated to Jilin UniversityMATERIALS: This experiment was carried out at the Central Laboratory,China-Japan Union Hospital, Jilin University between March 2003 and January 2004. Totally 77 healthy male Wistar rats were randomly divided into normal control group (n=7), simple ischemia group (n=14) and ischemia-reperfusion group (n=56). Among the rats in the simple-ischemia group, 7 rats suffered from blood flow block for 30 minutes and 7 rats for 60 minutes; Rats in the ischemia-reperfusion group were assigned into 8 subgroups according to 8 time phases, respectively at reperfusion for 30,60 minutes, 2, 4, 6,9, 12 and 24 hours following spinal ischemia, with 7 rats at each time phase.METHODS: Spinal ischemia-reperfusion injury animal models were created with Zivin method. The expressions of vascular endothelial intercellular adhesion molecule-1 (ICAM-1) mRNA and IL-1β mRNA following spinal ischemia-reperfusion injury were detected with reverse transcriptionpolymerase chain reaction, immunohistochemistry and immunofluorescent confocal laser scanning microscope technique.MAIN OUTCOME MEASURES: The expression of IL-1β mRNA, activity of IL-1 polypeptide, expression of ICAM-1 mRNA and protein and activity of myeloperoxidase (MPO).RFSULTS: Totally 77 animals were enrolled and all of them entered the stage of result analysis. ① The expression of IL-1β mRNA (A value)was significantly higher in the ischemia-reperfusion group than in the simple ischemia group and normal control group, with significant difference (respectively 1.07±0.33,0.60±0.22,0.57±0.12,t=3.751 7,11.852 6,P ＜ 0.01).② Activity of IL-1 polypeptide (A value )was significantly higher in the ischemia-reperfusion group than in the simple ischemia group and normal control group, with significant difference [respectively (33.7±3.2),(23.8±4.5), (23.1±2.1),t=2.798 8,9.962 7,P ＜ 0.01]. ③ ICAM-1 mRNA(A value)was significantly higher in ischemia-reperfusion group than in simple ischemia group and normal control group, with significant difference[respectively 0.94±0.12,0.52±0.11,0.51±0. 10,t=0.327 0,6.127 4, P＜0.01].④The expression of ICAM-1 protein was significantly higher at ischemiareperfusion for 4,6 and 12 hours than in simple ischemia group and normal control group, with significant difference [Respectively (316.90±26.00),(361.40±18.00),(406.00±23.00),(164.21±2.00),(180.00±32.00) μg/L,t=1.410 3,9.119 3 ,P ＜ 0.01]. ⑤ The activity of MPO was significantly higher at ischemia-reperfusion for 12 hours than in simple ischemia group and normal control group, with significant difference [respectively (15.00±2.00),(7.50±1.67),(6.67±1.00) nkat/g, t=3.012 2,P ＜ 0.01].CONCLUSION: Following reperfusion injury, inflammatory reaction in spinal cord is important molecular basis for causing blood spinal barrier impairment, and plays an important role in the process of secondary spinal cord injury.

Objective To explore the influence of pelvis obliquity in lateral position to acetabular component orientation during total hip arthroplasty (THA),and the method to correct.Methods Fifty patients (62 hips) were performed THA with posterolateral incision in lateral position by the same team.The patients were randomized and divided into experimental group (EX,with 25 cases,34 hips) and control group (CON,with 25 cases,28 hips).In EX group,the acetabular components were placed by means of the gradienter and plumb correcting technique during THA.While in CON group,the acetabular components were placed by traditional method during THA.The acetabular abduction angles were measured postoperatively,and compared between the two groups.Results The average obliquity of pelvis was-1.647°±4.512°in EX group when putting the patient in lateral position before correcting.Through the application of gradienter and plumb,the average abduction angle of acetabular component was 42.685°±3.355° postoperatively,with the difference of 1.962°±1.515° compared with the preoperative angles.And in CON group,the average abduction angle of acetabular component was 44.534°±4.844° postoperatively,with the difference of 4.244°±3.042°.The difference of abduction angle in CON group was much higher than that in EX group (P＜0.05).Conclusion The pelvic obliquity when putting the patient under lateral position will affect the surgeons'judgments of placing acetabular component during THA,furthermore,lead to inconsistency among the abduction angles obtained preoperatively,intraoperatively and postoperatively.By applying the correcting method with gradienter and plumb,the discrepancy can reduce obviously between the abduction angle measured postoperatively and that of measured during operation comparing with traditional method.

BACKGROUND:With the development of three-dimensional (3D) printing technology, 3D printed porous titanium scaffolds as bone substitutes have become a research hotspot. OBJECTIVE:To introduce and discuss the effects of each parameter of 3D printed porous titanium scaffolds on bone ingrowth, and to sum out the optimal parameters for bone ingrowth. METHODS:The first author retrieved PubMed, Springerlink and Medline databases with“three-dimensional (3D) printing, scaffold, titanium, bone ingrowth”as keywords for relevant articles published from 2006 to 2016. 125 articles were retrieved initial y, and final y 42 eligible articles were included for analysis. RESULTS AND CONCLUSION:Pore size, porosity, pore structures and surface modifications of 3D printed porous titanium scaffolds al make effects on bone ingrowth or osteoblasts in scaffolds. Scaffolds with appropriate pore size and porosity can promote the vascularization and provide adequate nutrition and oxygen supplement, to ensure high cel viability. Regulations of cel performances, such as cel attachment, proliferation and differentiation, are also affected by pore structures and nano-scale surface modification. Herein, a detailed combination of the parameters, as mentioned above, can create a better porous scaffold for better bone ingrowth. Hence, the high-stability interface between bone and scaffolds may be obtained through the parameter adjustment.

In order to improve teachers' teaching ability and manage teachers effectively, we try to organize teachers to carry out a series of activities in the form of "teaching club". We set up six teaching clubs according to the key points of teaching work and teaching hot spots. We explore the formation of "teaching club" as a means of modern teacher management model, through the implementation of the teacher-centered concept, establish an efficient and flexible management system, and establish and improve the active development of behavior and other strategies. Through a period of practice and exploration, we have gained benefits and even made breakthroughs in many aspects, such as the construction of teaching team, curriculum construction and teaching competition. The management strategies mentioned above provide new ideas for the development of teacher management.

Objective:To discuss the accuracy of stereolithography (SLA)-3D printing model in orthopedics and maxillofacial surgery,and to clarify the reliability of its clinical application.Methods:A total of 33 cases of SLA-3D printing models were randomly included (10 long bones,13 irregular bones and 10 prostheses),and the CT scanning and three-dimensional reconstruction were performed.According to the clinical application characteristics of the models,the max height (MH),max length (ML),max width (MW),width of the trochlear (WT),length of the trochlear (LT),length of the glenoid cavity (LGC),width of the glenoid cavity (WGC),distance of pubic tubercle-anterior superior iliac spine (DPI),diameter of the acetabulum (DA),diameter of the marrow cavity (DMC),anterior height of right ramus (AHRR) and posterior height of right ramus (PHRR) were selected to measure the original data and model data,respectively.The absolute / relative errors were calculated.Intraclass correlation coefficient (ICC) was used to evaluate the consistency of the data.The three-dimensional error analysis of the prosthesis model was carried out.Results:There were no significant differences in the anatomical parameters except MW of irregular bone (P＞0.05) in 33 cases of SLA-3D printing model.The values of ICC were all greater than 0.950;the maximum values of absolute / relative errors were-0.58 mm and-1.37％,respectively;the maximum 3D error of prosthesis model was 0.237 mm,and the average value was 0.132 mm.Conclusion:The CT data of SLA-3D model is highly consistent with the original data,and it is accurate and reliable in the diagnosis and treatment of the diseases in orthopedics and maxillofacial surgery.

This study summarizes the construction background, rules and regulations and institutional settings of the MOOC and Micro-course Club in the Second Hospital of Jilin University, discusses the means of teacher training for clinical teachers, and shows the application effect of the club. At the same time, the related problems encountered in the process of club construction are summarized and reflected. The construction of MOOC and micro-course clubs is conducive to improving the information-based teaching level of clinical teachers, and also provides new inspiration and ideas for the construction of medical clubs.

Objective:To investigate the therapeutic efficacy of enteral nutrition through percutaneous endoscopic gastrostomy/jejunostomy (PEG/PEJ) in patients with severe cerebral hemorrhage.Methods:Eighty-five patients with severe cerebral hemorrhage admitted to our hospital from January 2015 to December 2018 were enrolled into this retrospective study. According to ways of enteral nutrition, all 85 patients were divided into nasogastric tube group ( n=44) and PEG/PEJ tube group ( n=41). The clinical data were analyzed retrospectively, and the enteral nutrition treatment efficacy, incidence of complications, and length of hospital stays between the two groups were compared. Results:The incidences of diarrhea (14.6%, 6/41), gastric retention (34.1%, 14/41), and hypoproteinemia (26.8%, 11/41) in PEG/PEJ tube group were significantly lower than those in nasogastric tube group (38.6% [17/44], 59.1% [26/44], and 47.7% [21/44], P<0.05). However, the rate of obstruction ducts in PEG/PEJ tube group (34.1%, 14/41) was significantly higher than that in nasogastric tube group (11.4%, 5/44, P<0.05). As compared with the patients in nasogastric tube group, patients in the PEG/PEJ tube group had significantly shorter average length of hospital stays ([35.2±4.7] d vs. [37.6±5.4] d, P<0.05). The NRS2002 scores of patients in the nasogastric tube group and PEG/PEJ tube group after enteral nutrition treatment were 1.73±0.52 and 1.87±0.64, respectively, without significant difference ( P<0.05). Conclusion:The enteral nutrition treatment through PEG/PEJ could significantly reduce the incidences of diarrhea, gastric retention and hypoproteinemia, and shorten the average length of hospital stays in patients with severe cerebral hemorrhage; rate of obstruction of percutaneous endoscopic jejunostomy ducts should be reduced.