Percutaneous Transforaminal Endoscopic Diskectomy for Lumbar Disk Herniation: Young (Age <60 years) versus Older (Age ≥60 years) Patients.

BACKGROUND: We compare the differences in the efficacy of percutaneous transforaminal endoscopic diskectomy (PTED) between the younger (age <60 years) and older (age ≥60 years) patients with lumbar disk herniation (LDH). METHODS: From December 2016 to December 2017, 128 patients with symptomatic LDH underwent PTED and were followed up. Forty-four 60 years old and above, including 19 males and 25 females with an average age of 68.7 (61-82) years, were classified as the elderly age group. Eighty-four patients younger than 60 years were classified as the young age group, which included 48 males and 36 females with an average age of 44.7 (16-58) years. The visual analog scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores, and satisfaction rates of the two groups before and after surgery were compared. RESULTS: The operation was completed successfully in both groups. The average follow-up times of the elderly and young age groups were 18.47 ± 2.62 (12-23) and 17.90 ± 3.27 (12-23) months, respectively. One patient in the young age group had recurrence 7 months after surgery, and the symptoms were relieved after PTED was performed again. Two patients with nerve root injury after surgery in the young age group completely recovered after 2 months of conservative treatment. There were no significant surgical complications in the elderly age group. There was no significant difference in postoperative VAS, JOA, and MacNab scores between the two groups. The MacNab scores in the elderly age group were excellent for 28 patients, good for 10 patients, and fair for 6 patients; the satisfaction rate was 86.3%. In the young age group, scores were excellent for 63 patients, good for 14 patients, fair for 5 patients, and poor for 2 patients; the satisfaction rate was 91.7%. CONCLUSION: The clinical effectiveness of PTED for treatment of LDH in both elderly and young patients is satisfactory. Age is not a predictor of poor outcomes of PTED.

MMP2 promotes osteoblast differentiation and calcification of muscle-derived mesenchymal stem cells by interaction with miR-29b-3p.

Matrix metalloproteinase 2 (MMP2) was previously reported to play important role in the process of stem cell migration and various differentiation behaviors of muscle-derived mesenchymal stem cells (M-MSCs). However, its role and regulatory mechanism in the osteoblast differentiation and calcification of M-MSCs remain unclear. In the current study, we found that MMP2 could facilitate the osteoblast differentiation and calcification of muscle-derived mesenchymal stem cells by up-regulating the expression of some typical osteogenic differentiation phenotype markers, such as runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), and osteocalcin (OCN). Besides, we further demonstrated that MMP2 could be directly targeted by miRNA-29b-3p, which was validated by dual luciferase reporter gene and rescue assays. Moreover, increased expression of MMP2 could contribute to forming more calcium nodules representative for osteoblast calcification verified by the alizarin red staining, vice versa. In conclusion, we identified the role of miRNA-29b-3p/MMP2 relationship in regulating osteoblast differentiation and calcification of M-MSCs, which may complement the effect of MMPs family on the osteoblast differentiation to some extent, providing some potential clinical application value in the promotion of bone formation in the future.

Treatment of intra-articular calcaneal fractures with unilateral external fixator combined with limited internal fixation / 中国骨伤

<p><b>OBJECTIVE</b>To study the clinical effects of the unilateral external fixator combined with limited internal fixation such as cannulated lag screws for the treatment of intra-articular calcaneal fractures.</p><p><b>METHODS</b>From May 2007 to February 2012,52 patients (58 feet) with intraarticular calcaneal fractures were treated with unilateral external fixator and limited internal fixation such as lag screws. Forty-five patients (51 feet) were male,7 patients (7 feet) were female,ranging in age from 18 to 64 years,averaged 36.5 years. Time from injury to surgery was 4 to 13 (6.2 +/- 0.8) days. According to Sanders classification, there were 36 cases (40 feet) with type II fractures, 13 cases (15 feet) with type III fractures, 3 cases (3 feet) with type IV fractures. All patients were examed with X-ray and CT. Böhler angle, Gissane angle, length, width, height were measured on the radiographs, respectively. The function of the feet was assessed by the Maryland grading system.</p><p><b>RESULTS</b>Fifty-one patients(57 feet) were followed up for 5 to 16 months,with an average of 7.2 months. Calcaneal Böhler angle increased from (12.65 +/- 5.32) degrees preoperatively to (30.63 +/- 4.28) degrees postoperatively. The calcaneal Gissane angle decreased from (129.87 +/- 6.25) degrees preoperatively to (122.11 +/- 4.89) degrees postoperatively. The calcaneal length increased from (64.5 +/- 7.1) mm preoperatively to (71.3 +/- 5.7) mm postoperatively. The calcaneal width decreased from (34.6 +/- 5.7) mm preoperatively to (28.2 +/- 6.1) mm postoperatively. The calcaneal height increased from (30.2 +/- 5.2) mm preoperatively to (39.3 +/- 6.4) mm postoperatively. All of the comparison between preoperative and postoperative measurements revealed statistically significant (P < 0.05). The length,width, height, Böhler angle and Gissane angle were improved significantly (P < 0.05). According to the Maryland grading system, the result was excellent in 20 feet, good in 31 feet, fair in 4 feet, pour in 2 feet,excellent and good rate was 89.5%. Three feet with wound infection or flap necrosis were healed after wound debridement and dressing exchange.</p><p><b>CONCLUSION</b>The unilateral external fixation combined with limited internal fixation is a satisfactory treatment for intra-articular calcaneal fractures in short term with less damage, few complications and good functional recovery.</p>

Extraction and Detect on Immunization of Outer Membrane Protein of Bordetella bronchiseptica / 微生物学通报

P13-OMP (29.1). P13-OMP and OMP68 group challenged with P13 and P11 can be efectivly protected; P13-WCB group challenged with P13 and P11 can not be efectivly protected; the control group were died out. The P13-OMP and OMP68 of Bordetella bronchiseptica has good immunogenicity and protection, so the results of this study lay good theoretical foundation for OMP subunit vaccine.

Preparation and evaluation of chitosan-carboxymethylcellulose membrane for prevention of postoperative intestinal adhesion: An experimental study / 第二军医大学学报

Objective: To prepare and evaluate the effectiveness of chitosan-carboxymethylcellulose membrane in preventing postoperative intestinal adhesion. Methods: Chitosan-carboxymethylcellulose membrane was prepared with 1:1 ratio of chitosan and carboxymethylcellulose. Glutaraldehyde and ammonium aluminium sulfate were used for cross-linkage, glycerin for enhancing plasticity; and then the product was dried. The membrane was observed with scanning electron microscopy (SEM) and its tensile strength and breaking elongation were measured. Forty-eight SD rats with ileum injury were randomly divided into A, B and C groups (n=16). During operation, the injury in group A was treated with chitosan-carboxymethylcellulose membrane, in group B with chitosan membrane, and in group C without treatment (control group). The adhesion was observed on the 14th postoperative day. Results: The tensile strength of chitosan-carboxymethylcellulose membrane was 20 MPa and the breaking elongation was 65%. SEM showed that the morphology of the membrane had crossed fibroid structures and irregular pores. The severity of adhesion in group A and B was significantly lower than that in group C (P<0.01). Milder inflammatory changes and less fibrous proliferation were found in group A and B compared with those in group C. Epithelia rehabilitated better in group A than in group B, and the proliferation of fibroblast was not significant under electron microscope. In group C, epithelia rehabilitated slowly and fibroblasts excreted collagen actively. Conclusion: Chitosan-carboxymethylcellulose membrane is feasible for suturing during operation and is effective in reducing intestinal adhesion and it is superior to chitosan membrane.

Effect of carboxymethylchitosan on autocrine growth factor and morphology of fibroblasts cultured in vitro / 第二军医大学学报

Objective: To investigate the effect of carboxymethylchitosan on autocrine growth factor and morphology of fibroblasts cultured in vitro, so as to discuss the possible mechanism by which carboxymethylchitosan alleviates overheating and prevents adhesion in wound healing. Methods: Fibroblasts were cultured in vitro. Fibroblasts of passage 4-6 were treated with different concentrations of carboxymethylchitosan (0.01,0.1,1.0 and 10 mg/ml) for 4 days or with 0.1 mg/ml carboxymethylchitosan for 1, 2, 3, 4, 5, and 6 days. The levels of autocrine transforming growth factor-β1 (TGF-β 1) and epidermal growth factor (EGF) of fibroblasts were determined by ELISA and radioimmunoassay. The fibroblastic morphology was detected by transmission electron microscopy (TEM) and microscope after fibroblasts were treated with different strategies. Results: Carboxymethylchitosan (≥ 0.1 mg/ml) inhibited autocrine TGF-β1 of fibroblast in a time- and concentration dependent manner (P0.05). Carboxymethylchitosan (≥ 0.1 mg/ml) also inhibited the proliferation of fibroblasts and caused their ultrastructural changes. Conclusion: Carboxymethylchitosan (≥0.1 mg/ml) can inhibit fibroblasts proliferation and reduce tissue adhesion, possibly through altering fibroblast ultrastructure and selectively inhibiting secretion of TGF-β1.

Effect of nerve growth factor on denervated bone fracture healing in rats / 第二军医大学学报

Objective:To study the effect of nerve growth factor(NGF)on bone fracture healing of inflicted T_(10)spinal cord injury(SCI)complicated with tibia fracture in rats.Methods:Totally 120 rats were randomly divided into tihia fracture group (F group,n=40),T_(10)SCI+tibia fracture group(FS group,n=40),and T_(10)SCI+tibia fracture+NGF group(FSN group,n=40).Four weeks later,the fracture sites in the 3 groups were subjected to CT scanning;the maximum transverse diameter of the fracture ends and the gray scales of non-osseous area were measured;the changes of biomechanics property of the fracture ends were determined by three-point bending test;the bone morphometry,bone density,and histomorphology of callus were determined;the expression of OCN was detected by immunohistochemical method;the osteoblast ultrastructure was observed by TEM and the expression ofⅠ,Ⅱtype collagen were examined by Western blotting.Results:The maximum transverse diameter of F group was less than those of FS group(P