Effect of nitric oxide synthase inhibitor on proteoglycan metabolism in repaired articular cartilage in rabbits

Nitricoxide (NO )isanimportantregulatoryfactorandasignal transductionmoleculeintheprocessofcellgrowthanddifferentiation .Recentreportshaveindicatedthatnitricoxideiscloselyrelatedtothedisintegrationofarticularcartilage,becausehighexpressionofinducednitricoxidesynthase (iNOS)inhibitormRNAisdetectedinthearticularcartilageandiNOScanamelioratethecartilagemetabolisminpatientswithosteoarthritisorrheumaticarthritis .1,2 OurpreviousstudyshowedthatiNOScanamelioratethe qualityofrepairedcartilages ,t…     

The performance characteristics of a piezoelectric ultrasonic dental scaler

The objective of this work was to investigate the performance characteristics of a piezoelectric ultrasonic dental scaler using scanning laser vibrometry. The vibration characteristics of three standard piezoelectric tips were assessed with scanning laser vibrometry under various conditions: unconstrained, under a stream of flowing water, in a water tank, as well as subjected to loads to simulate clinical conditions. Subsequently, the tips were used to disrupt an in-vitro biofilm model of dental plaque, developed using a non-pathogenic Gram-negative species of Serratia (NCIMB40259).The laser vibrometry data showed that the oscillation pattern of the ultrasonic tip depends primarily on its shape and design, as well as on the generator power. Thin tips and high power settings induce the highest vibrations. Water irrigation of the tip and loads influence the tip performance by diminishing its vibration, while water volume increases it.Serratia biofilm was disrupted by the cavitation bubbles occurring around the scaler tip. The most effective biofilm removal occurred with the thinner tip.Understanding how the ultrasonic tip oscillates when in use and how it removes dental plaque is essential for gaining more knowledge regarding the cleaning mechanisms of the ultrasonic system. Cavitation may be used to remove plaque and calculus without a mechanical contact between the dental tip and the teeth. Better knowledge would enable dental specialists to understand and improve their techniques during routine cleaning of teeth. It will also lead to improving tip design and to the production of more effective instruments for clinical use.     

新型胸锁钩钢板治疗胸锁关节周围不稳定性骨折脱位的疗效观察

目的:探讨新型胸锁钩钢板治疗胸锁关节周围不稳定性骨折脱位的临床疗效。方法 :自2011年6月至2013年12月,应用胸锁钩钢板对32例成年胸锁关节骨折脱位患者进行手术治疗。其中男24例,女8例;年龄25~76岁,平均42岁;胸锁关节前脱位12例,胸锁关节后脱位5例,锁骨内侧端骨折10例,骨折合并脱位5例。胸锁关节前骨折脱位采用标准胸锁钩钢板,后脱位则在钢板钩的远端,即胸骨柄前方加用螺母和垫片,预防术后再脱位。根据Rockwood评分法评定疗效。结果 :患者手术过程中无并发症发生。术后复查X线片及CT显示胸锁关节解剖位置正常,内固定位置良好。32例均获得随访,时间6~24个月,平均10个月。术后3~6个月骨折达Ⅰ期愈合,胸锁关节无再脱位,锁骨内侧端解剖结构均恢复,功能满意,其中9例患者胸锁关节周围存在肿胀,但无疼痛等症状。Rockwood评分结果12.78±1.43;疗效优24例,良8例。结论:使用该新型胸锁钩钢板治疗胸锁关节周围不稳定性骨折,内植物固定确实可靠,安全性高,操作简便,为治疗此类创伤提供了一种可靠的方法。     

3D打印个体化钛笼结合Masquelet技术治疗跟骨感染性骨缺损

目的探讨局部皮瓣转移修复足跟部软组织缺损联合3D打印个体化钛笼、Masquelet技术自体肋骨植骨治疗跟骨感染性缺损的有效性和安全性。方法回顾性分析2017年1月至2019年1月,采用局部皮瓣转移修复足跟软组织缺损和3D打印个体化钛笼、Masquelet技术自体肋骨植骨等技术治疗5例跟骨感染性骨缺损的患者资料,男3例,女2例;年龄37.0岁(范围,17~52岁);车祸伤2例,高处坠落伤2例,碾压伤1例。全部病例采用分期手术治疗,一期骨水泥填塞跟骨缺损皮瓣覆盖创面。清创后软组织缺损:2例10 cm×8 cm,8 cm×7 cm、8 cm×5 cm和5 cm×3 cm各1例。跟骨体部缺损:2例4 cm×3 cm×2 cm、2例3 cm×3 cm×2 cm和1例3 cm×1 cm×1 cm。二期通过3D打印联合Masquelet技术自体肋骨植骨重建跟骨缺损。术后定期随访观察植骨愈合情况、跟骨形态、内固定位置,采用Maryland评分和美国足踝外科协会(American Orthopaedic Foot and Ankle Society,AOFAS)踝-后足评分评价足部功能。结果5例患者全部获得随访,随访时间18.2个月(范围,12~30个月)。一期手术后4例伤口愈合良好,1例于术后2个月发生深部感染,再次清创更换骨水泥后愈合。细菌培养:耐甲氧西林金黄色葡萄球菌3例、表皮葡萄球菌和大肠杆菌各1例。二期采用Masquelet技术自体肋骨植骨和3D打印个体性化钛网植入重建跟骨形状和结构。临床愈合时间4.32个月(范围,3~8个月);影像学检查跟骨植骨区域连续性骨小梁形成时间为13个月(范围,10~22个月)。术后12个月,Maryland评分为92分(范围,86~98分),其中优2例、良3例;AOFAS评分89.8分(范围,83~100分),其中优2例、良3例。1例一期术后发生深部感染,再次清创后治愈。结论3D打印个体化钛笼、Masquelet技术自体肋骨植骨重建跟骨是治疗跟骨感染性骨缺损的一种方法,术后疗效满意。     

数字化人工髋关节置换的术前设计

目的应用数字化影像技术对人工髋关节置换进行术前设计。方法应用数字化影像和数字模板在计算机上进行术前测量并选择假体型号，并与手术中实际应用的假体型号进行比较。结果术前设计假体型号与术中实际应用假体型号相比较，髋臼假体的准确率达71．59％，股骨假体准确率达78．04％。结论应用数字化技术对人工髋关节置换行术前设计具有较高的准确率和可信度。     

Influence of the induced membrane filled with syngeneic bone and regenerative cells on bone healing in a critical size defect model of the rat’s femur

IntroductionThe induced membrane technique for the treatment of large bone defects consists of a 2-stage procedure. In the first stage, a polymethylmethacrylate (PMMA) cement spacer is inserted into the bony defect of a rat’s femur and over a period of 2–4 weeks a membrane forms that encapsulates the defect/spacer. In a second operation the membrane is opened, the PMMA spacer is removed and the resulting cavity is filled with autologous bone.Since little effort has been made to replace the need for autologous bone this study was performed to elucidate the influence of different stem cells and the membrane itself on bone healing in a critical size femur defect model in rats.Especially the question should be addressed whether the use of stem cells seeded on a β-TCP scaffold is equivalent to syngeneic bone as defect filling in combination with the induced membrane technique.Materials and MethodsA total of 96 male Sprague-Dawley (SD) rats received a 10 mm critical size defect of the femur, which was stabilized by a plate osteosynthesis and filled with PMMA cement. In a second step the spacer was extracted and the defects were filled with syngeneic bone, β-TCP with MSC + EPC or BM-MNC. In order to elucidate the influence of the induced membrane on bone defect healing the induced membrane was removed in half of the operated femurs. The defect area was analysed 8 weeks later for bone formation (osteocalcin staining), bone mineral density (BMD) and bone strength (3-point bending test).ResultsNew bone formation, bone mineral density and bone stiffness increased significantly, if the membrane was kept. The transplantation of biologically active material (syngeneic bone, stem cells on b-TCP) into the bone defect mostly led to a further increase of bone healing. Syngeneic bone had the greatest impact on bone healing however defects treated with stem cells were oftentimes comparable.ConclusionFor the first time we demonstrated the effect of the induced membrane itself and different stem cells on critical size defect healing. This could be a promising approach to reduce the need for autologous bone transplantation with its’ limited availability and donor site morbidity.     

Traumatic Spino‐pelvic Dissociation with Bilateral Triangular Fixation

Objective

To evaluate the clinical outcomes of traumatic spino‐pelvic dissociation (TSD) treated with modified bilateral triangular fixation.

Methods

Eighteen consecutive patients of TSD were included in the study from March 2011 to March 2015, and the medical records of patients were reviewed retrospectively. There were 14 men and 4 women with an average age of 33.1 ± 1.4 years (range, 18–55 years). A total of 16 cases were caused by falling, and 2 cases were caused by traffic accident. All sacral fractures had associated injuries. According to the morphology of sacral fracture, U‐shaped fractures were present in 10 cases, H‐shaped fractures in 6 cases, and Y‐shaped fractures in 2 cases. According to Roy–Camille classification, there were 12 cases of type II and 6 cases of type III. All patients received surgical treatment with modified bilateral triangular fixation, and the sacral plexus decompression was performed simultaneously on 6 cases whose scores were more than 2 according to Gibbons classification and were found having traumatic canal stenosis or sacral nerve compression detected by preoperative imaging examination. Mears’ radiological evaluation criterion was applied to evaluate the reduction quality of fractures; Gibbons score was applied as the index of neurological deficiency healing, and the clinical outcome of fracture was evaluated with Majeed function assessment at last follow‐up.

Results

All patients were followed up continuously within an average of 32.4 ± 3.6 months (range, 22–48 months). All sacral fractures were healed in an average time of 11.3 ± 2.8 months (range, 8–28 months). According to the Majeed function evaluation, 12 cases were classified as excellent, 4 cases as good, and 2 cases as fair. Meanwhile, the anatomical reduction was obtained in 11 cases, satisfactory reduction in 6 cases, and unsatisfactory reduction in 1 case according to Mears’ radiological evaluation criterion. The average Gibbons score changed from 2.5 ± 0.2 preoperatively to 1.4 ± 0.5 24 months postoperatively, which had a significant difference (t = 2.15, P < 0.05).

Conclusion

Modified triangular fixation combined with internal fixations shows satisfactory clinical outcomes in the treatment of TSD, which is recommended as an effective and advanced surgical choice.

     

地塞米松对大鼠骨髓间充质干细胞凋亡的影响

背景：研究发现地塞米松能有选择性地促进骨髓间充质干细胞凋亡。目的：了解地塞米松对骨髓间充质干细胞凋亡的影响以及作用机制。方法：体外培养 SD 大鼠骨髓间充质干细胞,传至第 2 代后分两组培养,对照组不加地塞米松,实验组分别加入 10-9,10-8,10-7 mol/L 地塞米松,作用 3,6,12,24 h 后通过流式细胞仪检测凋亡率。MTT 法检测地塞米松对骨髓间充质干细胞增殖率的影响。取 10-7 mol/L 地塞米松作用骨髓间充质干细胞 24 h,反转录后检测 Caspase-3 和 bcl-2 的表达。结果与结论：与对照组比较,10-8,10-7 mol/L 地塞米松作用 12~24 h 对骨髓间充质干细胞的凋亡有明显促进作用,且与作用浓度和时间存在相关性,随着作用浓度的增大和时间的延长骨髓间充质干细胞的凋亡率有增高的趋势。MTT 结果表明10-8,10-7 mol/L 地塞米松作用 24 h 对骨髓间充质干细胞增殖率影响显著,这与上述流式细胞仪的检测结果相符。RT-PCR提示地塞米松作用组 Caspase-3 显著增高,bcl-2 降低。结果证实地塞米松可能是通过细胞外通路和（或）线粒体通路促进骨髓间充质干细胞凋亡。     

乙醇诱导大鼠骨髓间充质干细胞的凋亡机制

背景：有研究表明乙醇可诱导骨髓间充质干细胞凋亡并引起成骨细胞和破骨细胞数量减少,但乙醇对骨髓间充质干细胞凋亡的影响以及作用机制目前尚不十分清楚。目的：观察乙醇对大鼠骨髓间充质干细胞凋亡、线粒体功能的影响及bcl-2、Caspase-3表达的变化。方法：应用全骨髓培养法分离培养SD大鼠骨髓间质干细胞,置于0,100,200,300,400,500,600,700,800,900mmol/L乙醇中作用24h,MTT法进行细胞毒性药物实验;置于0,100,200,300,400,500mmol/L乙醇中作用6,12,24h,AnnexinV/PI双标记法流式细胞仪检测细胞凋亡和线粒体膜电位变化情况;置于0,427mmol/L乙醇中作用24h,RT-PCR法检测与凋亡有关的基因bcl-2和Caspase-3mRNA表达水平。结果与结论：MTT检测结果显示427mmol/L是乙醇对大鼠骨髓间充质干细胞生长的半数抑制浓度;AnnexinV/PI检测结果表明,与0mmol/L组比较,随作用时间的延长与乙醇浓度的增加,骨髓间充质干细胞凋亡率及线粒体跨膜电位的破坏水平明显升高（P〈0.05）。与0mmol/L组比较,乙醇作用24h后427mmol/L组bcl-2mRNA表达水平下降,Caspase-3mRNA表达水平增加（P〈0.05）。说明乙醇能诱导大鼠骨髓间充质干细胞凋亡,凋亡的发生可能与线粒体膜电位破坏、线粒体功能障碍、bcl-2和Caspase-3激活有关。     

乙醇诱导大鼠骨髓间充质干细胞的凋亡机制

背景:有研究表明乙醇可诱导骨髓间充质干细胞凋亡并引起成骨细胞和破骨细胞数量减少,但乙醇对骨髓间充质干细胞凋亡的影响以及作用机制目前尚不十分清楚。目的:观察乙醇对大鼠骨髓间充质干细胞凋亡、线粒体功能的影响及bcl-2、Caspase-3表达的变化。方法:应用全骨髓培养法分离培养SD大鼠骨髓间质干细胞,置于0,100,200,300,400,500,600,700,800,900mmol/L乙醇中作用24h,MTT法进行细胞毒性药物实验;置于0,100,200,300,400,500mmol/L乙醇中作用6,12,24h,AnnexinV/PI双标记法流式细胞仪检测细胞凋亡和线粒体膜电位变化情况;置于0,427mmol/L乙醇中作用24h,RT-PCR法检测与凋亡有关的基因bcl-2和Caspase-3mRNA表达水平。结果与结论:MTT检测结果显示427mmol/L是乙醇对大鼠骨髓间充质干细胞生长的半数抑制浓度;AnnexinV/PI检测结果表明,与0mmol/L组比较,随作用时间的延长与乙醇浓度的增加,骨髓间充质干细胞凋亡率及线粒体跨膜电位的破坏水平明显升高(P<0.05)。与0mmol/L组比较,乙醇作用24h后427mmol/L组bcl-2mRNA表达水平下降,Caspase-3mRNA表达水平增加(P<0.05)。说明乙醇能诱导大鼠骨髓间充质干细胞凋亡,凋亡的发生可能与线粒体膜电位破坏、线粒体功能障碍、bcl-2和Caspase-3激活有关。