BACKGROUND:During fracture healing, in addition to the need for appropriate biomechanical environment, the role of cytokines is also increasingly attracted attention.
OBJECTIVE:To study the effect of nerve growth factor and alpha-lipoic acid on fracture healing in rat models of femoral fracture.
METHODS:Sprague-Dawley rat models of femoral fracture were established. Seventy-two rats were randomly divided into three groups. In the control group, rats were intramuscularly injected with physiological saline. In the nerve growth factor group, rats were intramuscularly injected with nerve growth factor 200 ng/kg, once a day. In the combined therapy group, rats were intramuscularly injected with nerve growth factor 200 ng/kg and oral y taken alpha-lipoic acid 25 mg/kg, once a day. At 1, 2 and 3 weeks after administration, bony cal us volume was measured. Enzyme linked immunosorbent assay was used to measure serum bone morphogenetic protein-2 levels. Western blot assay was utilized to detect bone morphogenetic protein-2 protein expression at the broken end of fracture. Semi-quantitative RT-PCR was applied to examine vascular endothelial growth factor mRNA expression.
RESULTS AND CONCLUSION:(1) At 1 week after administration, no significant difference in bony cal us volume was detected among the three groups. Serum bone morphogenetic protein-2 level, bone morphogenetic protein-2 protein expression, and vascular endothelial growth factor mRNA expression were significantly higher in the nerve growth factor group and combined therapy group compared with the control group (P<0.05), but no significant difference was found between the two groups. (2) At 2 weeks after administration, the amount of cal us, serum bone morphogenetic protein-2 levels, bone morphogenetic protein-2 protein expression, and vascular endothelial growth factor mRNA levels were significantly higher in the nerve growth factor group and combined therapy group compared with the control group (P<0.05). Above expression levels were higher in the combined therapy group than in the nerve growth factor group (P<0.05). (3) At 3 weeks after administration, serum bone morphogenetic protein-2 levels, bone morphogenetic protein-2 protein expression, and vascular endothelial growth factor mRNA levels were significantly decreased in the nerve growth factor group. However, above expression levels were stil high in the combined therapy group, and significantly higher than in the nerve growth factor group (P<0.05). (4) These results indicate that nerve growth factor combined with alpha-lipoic acid had better effects on the fracture healing compared with the nerve growth factor alone.

OBJECTIVETo evaluate the effect of panaxynol (PAN) on delayed type hypersensitivity and possible mechanism.

METHODAllergic contact dermatitis (ACD) was induced by DNCB as a delayed type hypersensitivity (DTH) model to observe effect of PAN on auricle inflammation including pathological injury. Proliferation of T lymphocytes was induced by ConA and measured by MTf method. IFN-gamma secretion of splenocyte induced by ConA was detected by ELISA.

RESULTThe swelling degree of auricle and pathological injury in ACD mice was reduced significantly by treated with PAN in induction phase. Proliferation of T lymphocytes induced by ConA in vitro was inhibited significantly by PAN, By contrast, no detectable effect was observed in resting splenocyte. IFN-y induced by ConA in splenocytes was inhibited markedly by PAN from 10 micromol x L(-1) and from 6 h.

CONCLUSIONThe results showed that DTH was inhibited by PAN mainly in induction phase and this effect may be related with the inhibition on T lymphocytes proliferation and secretion of IFN-gamma.

Animals ; Cell Proliferation ; drug effects ; Concanavalin A ; metabolism ; Dermatitis, Allergic Contact ; drug therapy ; immunology ; metabolism ; Diynes ; pharmacology ; therapeutic use ; Fatty Alcohols ; pharmacology ; therapeutic use ; Female ; Interferon-gamma ; secretion ; Male ; Mice ; Mice, Inbred ICR ; Spleen ; drug effects ; pathology ; secretion ; T-Lymphocytes ; drug effects ; pathology

Objective:To study the application of students as standardized patients in orthopedical practice teaching of foreign medical students.Methods:A total of 116 students who received Surgical practice teaching in Affiliated Renhe Hospital of China Three Gorges University from January 2014 to December 2017 were randomly divided into two groups. Bedside teaching model was adopted in the control group ( n=58) to help the interns manage the in-patients under the guidance of the teacher. Additional teaching using standardized patients was applied 1 to 2 times per week in the experimental group ( n=58) on the basis of control group. After the teaching, practical test and assessment survey were adopted to evaluate the effectiveness of teaching. SPSS 13.0 was used to analyze the data by t-test. Results:The scores of the practical test of the experimental group were significantly higher than those of control group, such as history taking [(15.23±3.15) vs. (13.56±3.54), P=0.008], physical examination [(17.24±4.23) vs. (10.32±3.75), P=0.000], and basic skill [(17.32±2.58) vs. (13.22±3.65), P=0.000]. The assessment survey showed that learning motivation [(8.25±1.04) vs. (4.82±0.93), P=0.000], and communication ability [(6.22±1.12) vs. (5.59±0.89), P=0.001] of the experimental group were effectively improved than those of the control group. Conclusion:The teaching mode using standardized patients can effectively improve the learning motivation and clinical practical skills of foreign medical students, as well as the teaching quality.

BACKGROUND: Three-dimensional (3D) printed bone tissue engineering scaffolds have been widely used in research and clinical applications. β-TCP is a biomaterial commonly used in bone tissue engineering to treat bone defects, and its multifunctionality can be achieved by co-doping different metal ions. Magnesium doping in biomaterials has been shown to alter physicochemical properties of cells and enhance osteogenesis. METHODS: A series of Mg-doped TCP scaffolds were manufactured by using cryogenic 3D printing technology and sintering. The characteristics of the porous scaffolds, such as microstructure, chemical composition, mechanical properties, apparent porosity, etc., were examined. To further study the role of magnesium ions in simultaneously inducing osteogenesis and angiogenesis, human bone marrow mesenchymal stem cells (hBMSCs) and human umblical vein endothelial cells (HUVECs) were cultured in scaffold extracts to investigate cell proliferation, viability, and expression of osteogenic and angiogenic genes. RESULTS: The results showed that Mg-doped TCP scaffolds have the advantages of precise design, interconnected porous structure, and similar compressive strength to natural cancellous bone. hBMSCs and HUVECs exhibit high proliferation rate, cell morphology and viability in a certain amount of Mg²⁺. In addition, this concentration of magnesium can also increase the expression levels of osteogenic and angiogenic biomarkers. CONCLUSION: A certain concentration of magnesium ions plays an important role in new bone regeneration and reconstruction. It can be used as a simple and effective method to enhance the osteogenesis and angiogenesis of bioceramic scaffolds, and support the development of biomaterials and bone tissue engineering scaffolds.
Biocompatible Materials ; Biomarkers ; Bone and Bones ; Bone Marrow ; Bone Regeneration ; Cell Proliferation ; Compressive Strength ; Endothelial Cells ; Humans ; In Vitro Techniques ; Ions ; Magnesium ; Mesenchymal Stromal Cells ; Methods ; Osteogenesis ; Porosity ; Printing, Three-Dimensional ; Veins

Objective:To observe the changes in acromiaohumeral distance(AHD) in patients undergoing the modified arthroscopic double-button Latarjet procedure for recurrent anterior shoulder dislocation complicated with glenoid bone defect.Methods:A retrospective study was performed of the 52 patients who had undergone the modified arthroscopic double-button Latarjet procedure from October 2014 to October 2016 at Department of Sports Medicine, The First Affiliated Hospital to Shenzhen University for recurrent anterior shoulder dislocation complicated with glenoid bone defect. They were 33 males and 19 females, having 30 left and 22 right shoulders affected. Their ages ranged from 19 to 45 years(mean, 29.6 years). Their glenoid bone defects ranged from 17% to 30%(mean, 23.4%). CT scans were performed on the surgery side to observe the healing and reshaping of the bone grafts and to measure the AHDs of healthy shoulder, immediately, 6, 18 and 36 months after operation. Their American Shoulder and Elbow Surgeons(ASES), Rowe and Walch-Duplay scores were recorded before operation and at the final follow-up for comparison.Results:The follow-up time for this series ranged from 37 to 44 months (mean, 40.6 months). The AHDs at immediate postoperation(9.6 mm ± 0.7 mm), 6 months postoperation(8.6 mm ± 0.9 mm), 18 months postoperation (8.0 cm ± 0.8 cm) and 36 months postoperation(7.9 cm ± 0.8 cm) were significantly wider than the healthy side value (7.8 mm ± 0.8 mm)( P<0.05). The ASES, Rowe and Walch-Duplay scores at the final follow-up (93.9±3.2, 94.5±2.7 and 95.7±3.6) were significantly improved than the preoperative values (67.3±9.1, 40.1±4.2 and 63.5±9.0) ( P<0.05). The final follow-ups observed no symptoms or signs of chronic shoulder pain, rotator cuff injury or acromion impingement. Conclusion:As the AHD becomes wider rather than narrower after arthroscopic double-button Latarjet procedure for recurrent anterior shoulder dislocation complicated with glenoid bone defect, no subsequent rotator cuff injury may happen due to the uplift of the humeral head after the modified arthroscopic double-button Latarjet procedure.

OBJECTIVE: To testify the spatial relationship between the subscapularis muscle splitting window and the axillary nerve in modified arthroscopic Latarjet procedure, which could provide anatomical basis for the modification of the subscapularis muscle splitting. METHODS: A total of 29 adult cadaveric shoulder specimens were dissected layer by layer, and the axillary nerve was finally confirmed to walk on the front surface of the subscapularis muscle. Keeping the shoulder joint in a neutral position, the Kirschner wire was passed through the subscapularis muscle from back to front at the 4 : 00 position of the right glenoid circle (7 : 00 position of the left glenoid circle), and the anterior exit point (point A, the point of splitting subscapularis muscle during Latarjet procedure) was recorded. The vertical and horizontal distances between point A and the axillary nerve were measured respectively. RESULTS: In the neutral position of the shoulder joint, the distance between the point A and the axillary nerve was 27.37 (19.80, 34.55) mm in the horizontal plane and 16.67 (12.85, 20.35) mm in the vertical plane. CONCLUSION In the neutral position of the shoulder joint, the possibility of axillary nerve injury will be relatively reduced when radiofrequency is taken from the 4 : 00 position of the right glenoid (7 : 00 position of the left glenoid circle), passing through the subscapularis muscle posteriorly and anteriorly and splitting outward.
Adult ; Humans ; Shoulder ; Rotator Cuff/surgery* ; Arthroscopy/methods* ; Scapula/surgery* ; Shoulder Joint/surgery* ; Cadaver ; Joint Instability/surgery*