Objective To compare the clinical outcomes of posterior lumbar interbody fusion(PLIF) using simple cage alone fusion with pedicle screw fixation and autogenous bone grafting and cage fusion with pedicle screw fixation in adult spondylolisthesis. Methods From March 2003 to March 2004,Twenty-seven patients with lumbar spondylolisthesis were divided in two groups. In group A, 15 patients were treated by PLIF using simple cage alone fusion with pedicle screw fixation, including 4 males and 11 females, aging 53-68 years. Isthmic defects were located at L4 in 9 cases, at L5 in 6 cases. Four patients were smokers. The preoperative mean disc space height was 5.4±2.3 mm, the mean percentage of slip was 36.8%±7.2%. In group B, 12 patients were treated by PLIF using autogenous bone grafting and cage fusion with pedicle screw fixation, including 3 males and 9 females, aging 56 years. Isthmic defects were located at L4 in 8 cases, at L5 in 4 cases. Five patients were smokers. The preoperative mean disc space height was 5.7±2.5 mm, the mean percentage of slip was 37.8%±6.2%. Two groups were compared in the amount of blood loss, duration of hospitalization, back pain, radiating pain, fusion rate, the intervertebral disc space height, the postoperative degree of slip and the fusion rate. Results All patients were followed up for 24-38 months. The mean follow-up was 29(24-36) months in group A and 26(24-38) months in group B. There were no statistically significant differences in follow-up period, age,sex, the location of isthmic defects, smoking, the preoperative disc space height and the percentage of slip between two groups (P>0.05). There were no statistically significant differences in the amount of blood loss, the duration of hospitalization, the fusion time between two groups(P>0.05). But there were statistically significant differences in the back pain score, the radiating pain score and the fusion rate between two groups(P<0.05).The postoperative disc space height and the degree of slip of the last follow-up were 5.8±2.2 mm and 25.6%±7.2% in group A, 6.2±2.5 mm and 24.1%±7.4 % in group B, showing statistically significant difference (P<0.05). Conclusion The PLIF using autogenous bone grafting and cage fusion with pedicle screw fixations is more beneficial to improving the fusion rate and preventing long-term instabilities than simple cage alone fusion with pedicle screw fixation in adult spondylolisthesis.

BACKGROUND:The structure of tissue engineering carrier affects the bio-action of cells greatly.OBJECTIVE: To investigate the biological characteristics of bone marrow stem cells (MSCs) in different concentrations of alginate combined with de-antigen bone xenograft (DBX).DESIGN: Observational trial.SETTING: PLA Institute of Trauma and Orthopedics, the Fourth Military Medical University of Chinese PLA.MATERIALS: Alginate, calcium chloride, MSCs, bone xenograft.METHODS: Bovine cancellous bone was out into cubes, which were degreased, deproteinized and then lyophilized.Cubes in pore size within 300-500 μm were selected for use after ethylene oxide sterilization. The purified sodium alginate was dissolved in DMEM cell culture medium of concentrations as different as 0.5%, 2%, 8% and 16%; 1×1012 L-1 induced MSCs were blended with isopyknic alginate-DMEM and compounded with DBX at a status of 0.5 Mpa negative pressure for 5 minutes in order to make a cell suspension fully fill into the pores of the cancellous bone. Then alginate was crosslinked with 50 g/L calcium gluconic acid for 30 seconds. The complex was put into a CO2 incubator and cultured for 4 days. The gel compound and cell growth in the pores of the complex were grossly observed with an inverted microscope. Status of cell growth in the complex with different concentrations of alginate was observed with scanning electron microscopeMAIN OUTCOME MEASURES: Compound status of alginate and bone xenograft, cell growth status and matrix secretion in compound carries.RESULTS: When the concentration of alginate was 0.25% or 1%, alginate was equally combined in DBX, while that of 4% and 8% only combined on the surface of cancellous bone. After in vitro cultured for 4 days, alginate of 0.25% were broken off from DBX surface. But alginate of 1% was equally combined with DBX pores with cells secreting well in alginate. Development of cells in alginate of 4% was restricted and no cells were seen in alginate of 8%.CONCLUSION: Alginate of 1% is suitable for constructing the carrier of bone tissue engineering with bone xenograft.

BACKGROUND: Alginic acid has a relatively mild gel condition and good biocompatibility, and it has been widely used in bio-tissue engineering.OBJECTIVE: To construct bone tissue engineering scaffolds using alginate gel composite bone xenograft approach, and to observe the cell biological properties and in vivo osteogenic potential in scaffolds.METHODS: The bone marrow was harvested from two 2-week-old New Zealand rabbits, 1 ×10~(-8)mol/L recombinant human bone morphogenetic protein-2 was used to induce bone marrow mesenchymal stem cells. The induced bone marrow mesenchymal stem cells at the second generation were incubated into 1% sodium alginate gel, after cultured for 4 days, the cell morphology in gel was observed by hematoxylin-eosin staining. Bone marrow mesenchymal stem cells at the second generation were divided into simple DMEM gel group and DMEM containing 1% sodium alginate gel group, followed by a culture of 7 days. Then bone morphogenic protein-2 immunohistochemical staining was performed. A total of 24 nude mice were randomly divided into two groups, both sides of the thigh muscle pockets were implanted with bone marrow-derived mesenchymal stem cells/alginate gel/bovine cancellous bone complex as an experimental group, with bone marrow-derived mesenchymal stem cells/bovine cancellous bone as a control group. At 2 and 4 weeks post-operation, the osteogenesis in the composite was observed by histological examination, the percentage area of new bone or cartilage was determined using image analysis system.RESULTS AND CONCLUSION: The bone marrow-derived mesenchymal stern cells in the sodium alginate gel exhibited a well-stacked morphology, they suspended in a gel, showing cell division and mitosis phase. In the simple DMEM gel group and DMEM gel containing 1% sodium alginate group, the immunohistochemical results showed that, cell division and proliferation were normal, with prominence at a variety of forms, large nucleus, and clear nucleolus. The bone morphogenetic protein-2 expression had no significant difference between the simple DMEM gel group and DMEM gel containing 1% sodium alginate group (P>0.05).Scanning electron microscopy revealed that, the alginate gel evenly composited in bovine cancellous bone micropores, cell grew at different planes. Animal experiments showed that there were significant differences regarding the percentage of new bone or cartilage area between the experimental group and control group at 2 and 4 weeks postoperation (P< 0.05). It is indicated that constructing bone tissue engineering scaffolds by using alginate gel/bovine cancellous bone, complies with the ultra-structural principle of tissue engineering scaffolds, can maximize the cell loads, achieve good bio-performance, without adverse affects on the proliferation, osteogenic phenotype and related biological properties of bone marrow-derived mesenchymal stem calls, the in vivo osteogenic efficiency was high.

Objective: To observe the clinical efficacy of minimally invasive vitreous surgery (MIVS) for special rhegmatogenous retinal detachment (RRD) in children and adolescents. Methods: A retrospective clinical comparative study. Fourteen eyes with special type of RRD in 14 children and adolescents who received the MIVS treatment from January 2014 to January 2019 in Ophthalmology Department of The First Affiliated Hospital Ophthalmology of Air Force Military Medical University, were included in this study. Among them, 8 eyes from 8 males and 6 eyes from 6 females. The age of them ranged from 5 to 17, with the mean age of 12.64±4.11 years. The course of disease was ranged from 1 d to 1 year, and the average of it was 30 d. All the eyes developed the special type RRD, including pseudophakic and aphakic retinal detachment, giant retinal tear with retinal detachment, choroidal detachment associated with retinal detachment, and RRD with ocular dysplasia. In the 14 eyes, there was 2 eyes with retinal detachment in 1 quadrant, 4 eyes in 2 quadrants, 1 eye in 3 quadrants and 7 eyes in total 4 quadrants. All the eyes were treated with 23G or 25G MIVS and filled with irrigation solution, air and silicone oil. In addition, 10.4 months' follow-up for average after surgery were taken to observe the occurrence of retinal reattachment, BCVA and related complications in the eyes. Results: In the 14 eyes, 13 (92.9%) of them attained retinal reattachment and 1 eye (7.1%) got a poor retinal reattachment after one operation. At the last follow-up, all the 14 eyes (100.0%) attained retinal reattachment and 5 of them at the filling state of silicone oil. The vision of 8 eyes (57.1%) were improved, 4 eyes (28.6%) have no notable changes and 2 eyes decreased (14.3%). During the operation, iatrogenic retinal breaks were occurred in 1 eye, and silicone oil entered underneath the retina in 1 eye. After the operation, 1 eye suffered a relapse of retinal detachment after the removal of silicone oil and then were filled with it again. Conclusions MIVS is a safe and effective way to treat the special type RRD among the children and adolescents. The rate of retinal reattachment is 92.9% after one surgery and 100.0% at the last follow-up. Therefore, MIVS can help most of eyes with special type RRD to get a stable and improved vision.

Objective To investigate the efficacy of arthroscopic rotator cuff repair plus Bankart repair for anterior shoulder dislocations combined with rotator cuff rupture in patients above 40 years old.Methods A retrospective case series study was conducted to analyze the clinical data of 23 patients above 40 years old with anterior dislocation of shoulder joint and rotator cuff tear in Honghui Hospital Affiliated to Medical College of Xi'an Jiaotong University from January 2010 to September 2015.There were 10 males and 13 females,aged 40-71 years [(58.1 ± 10.3) years].All patients underwent arthroscopic rotator cuff repair plus Bankart repair.The visual analogue scale (VAS) was used to evaluate pain,the Oxford shoulder instability score (OSIS) was used to evaluate shoulder stability,and ConstantMurley shoulder score was used to evaluate shoulder function.Meanwhile,the range of motion (ROM) of shoulder joint,complications and subjective efficacy feedbacks from the patients were recorded.Results All patients were followed up for 13-46 months [(24.2 ± 10.1) months].Before operation and at the last follow-up,there was significant decrease in the VAS score [(0.6 ± 0.2) points vs.(3.8 ± 1.2)points] and the mean OSIS score [(19.7 ± 5.5) points vs.(47.1 ± 14.1) points];significant increase was found in the Constant-Murley score [(79.1 ± 10.8) points vs.(36.6 ± 6.4) points],the ROM of ante-flexion [(149.1 ± 22.0) vs.(65.8 ± 14.7)],abduction [(119.4 ± 23.2) ° vs.(69.1 ± 16.7) °] and external rotation [(45.0 ± 11.4) ° vs.(8.9 ± 2.7) °] (all P ＜ 0.05).No significant difference was found in the ROM of internal rotation (P ＞ 0.05).There were no significant differences in the mean VAS score and OSIS score between the affected and unaffected shoulders (P ＞ 0.05),but the former had a significantly lower Constant-Murley score than the latter [(79.1 ± 10.8)points vs.(87.7 ± 9.3) points,P ＜ 0.05].In terms of the comparison of ROM,there was no significant difference in joint ante-flexion and internal rotation (P ＞ 0.05),but the affected shoulder had significantly lower ROM of external rotation and abduction [(45.0 ± 11.4) °and (119.4 ± 23.2) °] than the unaffected one [(55.9 ± 13.8) °and (153.1 ± 23.7)°] (P ＜ 0.05).The excellent-good rate of efficacy based on the subjective feedbacks from patients was 78％.Up to the last follow-up,none of the patients had wound infection or recurrent dislocation.Conclusions Arthroscopic rotator cuff repair plus Bankart repair can significantly relieve the pain,improve joint function and range of motion.Compared with the unaffected shoulder,the affected one had slight loss of function and decreased mobility in abduction and external rotation.

Objective To investigate whether vascular endothelial cells in choroidal neovascularization whether hypoxia condition can up-regulate SNAI1 and activate matrix metalloproteinase (MMP)2 and MMP9 therefore to participate in choroidal neovascularization(CNV).Methods Sixteen SPF male C57 mice aged 6-8 weeks were divided into control group and model group.CNV models were induced by retinal laser photocoagulation,and flatmount and frozen sections of retinal pigment epithelium (RPE)-choroid-sclera compound were prepared at 7 days after modeling.The CNV in flat-mount was examined by Isolectin B4 staining,and the location of SNAI1,MMP2 and MMP9 in frozen sections was determined by immunofluorescence technology.The expression of SNAI1,MMP2 and MMP9 at mRNA level in CNV was detected by real-time fluorescence quantitative PCR (real-time PCR).The use and care of experimental animals complied with Statement for the Use of Animals in Ophthalmic and Visual Research.The RF/6A cells were divided into normoxia group and hypoxia group and cultured for 24 hours in 5％ CO2condition and mix condition of 94％ N2,5％ CO2 and 1％ O2,respectively.The expression of SNAI1,MMP2 and MMP9 in the cells at mRNA and protein levels was detected by real-time PCR and Western blot assay,respectively.Small interfering RNA of SNAI1 (siSNAI1) was transfected into the cells,and then the expression of MMP2 in the cells at mRNA and protein levels was detected by real-time PCR and Western blot assay,respectively,and the migrating number of the cells was assayed by Transwell chamber assay.Results CD31 and SNAI1 positive-response cells were seen in RPE-choroid-sclera flat-mounts under the laser scanning confocal microscope.The relative expression levels of SNAI1mRNA and MMP2 mRNA in RPE-choroid-sclera tissues were higher in the model group than those in the control group (SNAI1 mRNA:1.291 ±0.060 vs.0.759±0.074,P =0.001;MMP2 mRNA:1.610±0.424 vs.0.772 ±0.080,P =0.044).The expression of MMP9 mRNA was not significantly elevated between model group and control group (P＞0.05).The relative expression level of MMP2 mRNA was higher in comparison with MMP9 mRNA in the model group (P＜0.01).The relative expressions of hypoxic induced factor 1α (HIF-1α),SNAI1 and MMP2 at mRNA level and protein level in RF/6A cells were significantly higher in the hypoxia group than those in the normoxia group (all at P＜0.05) and no considerable difference was seen in MMP9 mRNA expression between the two groups (P＞0.05).The relative expressions of MMP2 mRNA in the cells were 0.217±0.036 and 0.818±0.105,and those of MMP2 protein in the cells were 0.236±0.009 and 1.043±0.120 in the hypoxia+siSNAI1 group and only hypoxia group,respectively,with significant differences between them (P =0.002,0.003).The migrating number of the cells was (254.60 ±71.31)/field in the hypoxia+siSNAI1 group,which was significantly less than (534.10±96.21) /field in the control group (P =0.029).Conclusions The hypoxic environment at CNV can activate MMP2 by up-regulating the expression of SNAI1,which promotes the migration of vascular endothelial cells and therefore participates in CNV formation,and the intervention of SNAI1 activation under the hypoxic condition can inhibit this process.

Objective:To analyze the optical coherence tomography (OCT) imaging characteristics in patients with Coats disease and their value in predicting macular fibrosis.Methods:A nested case-control study was performed.A total of 43 patients (43 eyes) diagnosed with Coats disease through color fundus photography, ocular B-scan ultrasonography, fundus fluorescein angiography, and spectral-domain OCT examination were enrolled from January 2008 to October 2021 at the Xijing Hospital.Among them, there were 40 males and 3 females, aged from 2 to 60 years old, with a median age of 13 years.Macular fibrosis was used as an indicator of poor prognosis, and patients were divided into two groups based on whether macular fibrosis occurred at the end of follow-up.The differences in OCT characteristics between two groups were compared and logistic regression analysis was used to identify the risk factors for macular fibrosis.This study adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Xijing Hospital of Fourth Military Medical University (No.KY20202009-C-1).Results:The OCT clinical features of 43 cases of Coats disease included intraretinal hard exudates in 43 eyes (100%), subretinal fluid in 21 eyes (48.8%), macular cysts in 17 eyes (27.9%), subretinal exudates in 9 eyes (20.9%), anterior retinal hyperreflective dots in 7 eyes (16.3%), epiretinal membrane in 21 eyes (48.8%), and intraretinal fluid in 22 eyes (51.2%).In color fundus photos of 41 eyes, 38 eyes (93.0%) had hard exudates distributed in the posterior pole and 27 eyes (65.9%) had the mid-peripheral region.OCT examination showed that hard exudates were distributed in the inner nuclear layer in 35 eyes (81.4%) and the outer nuclear layer in 33 eyes (76.7%).Among 21 eyes with exudative retinal detachment detected by OCT, 9 eyes (42.9%) were detected by fundus photography and 18 eyes (85.7%) were detected by B-scan ultrasonography.The proportions of eyes with subretinal fluid and subretinal exudates were higher in the macular fibrosis group than in the non-macular fibrosis group, and the differences were statistically significant ( χ2=20.755, P<0.001; χ2=6.133, P=0.013).Logistic regression analysis showed that the presence of subretinal fluid was a risk factor for macular fibrosis (odds ratio=48.345, 95% confidence interval: 4.272-547.066, P=0.002). Conclusions:OCT examination can detect subretinal fluid, subretinal exudates, macular cysts, macular exudates, and hyperreflective spots in the retina of patients with Coats disease.Subretinal fluid is a risk factor for macular fibrosis.