负压与BMSCs膜片促进细胞定植和体内成骨的探讨

目的:研究经过负压处理的TCP支架材料与细胞复合后的体内成骨能力。方法:将TCP支架材料负压处理,和骨髓基质细胞(BMSCs)细胞共培养一段时间后,成骨诱导2周,电镜下观察支架材料和细胞复合情况。再将该复合物与BMSCS细胞膜片复合,植入到裸鼠皮下,8周后作组织切片,HE染色和Masson染色,观察其体内成骨能力。结果:负压(有细胞)+膜片组异位移植8周后,内部可见大量胶原纤维和成骨纤维,在团块样组织内部可见大量成骨细胞,并有血管形成。对照组仅有个别细胞密集区,胶原纤维和成骨纤维较少。空白组未见类似情况。结论:经过负压+骨髓基质细胞膜片处理的TCP支架材料,在体内有成骨潜能。     

中国汉族成人正常（牙合）牙体舌侧形态的测量研究

对中国汉族年轻成人正常（牙合）牙齿的舌侧形态进行三维测量,为研发基于中国人牙体舌侧形态的舌侧直丝弓托槽提供数据参考。方法：采用上海正雅齿科科技有限公司开发的数字化正畸设计系统软件,对普查获得的64副中国汉族正常（牙合）个体的牙齿模型进行三维扫描,并对三维数字模型舌侧面进行计算机定点及测量分析。结果：获得正常（牙合）人群牙齿舌侧的轴倾度、转矩角、冠凸距和尖牙与磨牙补偿角指标的参考值,与国内相关研究结果相近。结论：本研究的测量结果可用于研发中国人舌侧直丝弓托槽标准型。     

无牙颌种植修复设计

牙列缺失后,常存在颌位关系异常,同时口腔黏膜组织萎缩变薄,敏感度增加,义齿难以获得良好的固位及咀嚼功能。种植修复能够降低骨吸收量,增加义齿稳定性,减少戴牙后疼痛,是恢复患者咀嚼功能的有效方法。但患者个体差异导致的咬合力大小,颌间距离,牙槽骨高度、宽度及质量,黏膜厚度等条件均有差异,不同医师提出的治疗方案各异,难以统一。本文拟就无牙颌种植修复常见问题及设计时应考虑的因素作以讨论。     

锥形束CT中下颌第三磨牙与下颌管的关系及其与阻生类型的相关性分析

目的:研究在曲面断层片上表现为下颌管与下颌第三磨牙影像重叠的患者,其二者在锥形束CT(CBCT)上的位置关系,为临床风险评估提供参考。方法:研究184颗(146例患者)在曲面断层片上表现为与下颌神经管有影像重叠的下颌第三磨牙,在CBCT上其牙根与下颌神经管的位置关系。分析两者之间位置关系与阻生类型、性别、曲面断层片上下颌神经管骨白线是否可见的相关性。测量下颌第三磨牙与下颌神经管接触的患者其接触的长度及宽度,分析接触长度、宽度与牙根和下颌神经管相对位置的相关性。结果:CBCT图像上下颌第三磨牙与下颌神经管之间是否接触,与其在颌骨内的深度相关,低位阻生接触可能大(P=0.002),与性别相关,女性多(P=0.020);当曲面断层片中下颌神经管骨白线不可见时,接触可能大(P=0.001)。当下颌神经管与牙根舌侧接触时,接触的长度、宽度可能较大。结论:CBCT与曲面断层片相比能更好地体现下颌阻生第三磨牙与下颌神经管的关系,提供更准确的术前风险评估。     

脂肪性肝病与胃食管反流病的相关性研究

目的评估脂肪性肝病(FLD)与胃食管反流病GERD之间的关系。方法选取2 000例受试者,采用较简便的胃食管反流病问卷(GerdQ)作为初筛GERD诊断标准,对入选者均进行腹部超声波等检查,分析FLD与GERD关系。结果对2 000例患者利用GerdQ评估GERD诊断情况,有176例(8.8%)诊断为GERD,女68人(38.64%),男108人(61.36%);脂肪肝患者760例,患病率38.0%,在脂肪肝组中,男女性GERD症状的GerdQ阳性率分别为13.77%和12.24%,两者无明显差异(P>0.05)。脂肪肝人群发生GERD症状的患病率与对照组存在统计学差异(P<0.05)。结论脂肪肝与GERD显著相关,控制脂肪肝发展可以降低GERD发病率。     

法舒地尔通过Rho-ROCK通路抑制高糖诱导的单核细胞与内皮细胞黏附

目的观察Rho激酶抑制剂法舒地尔能否抑制高糖诱导的单核细胞(THP-1)与人脐静脉内皮细胞黏附,初步探讨其潜在机制。方法使用荧光显微镜观察荧光标记的THP-1与人脐静脉内皮细胞黏附。血管细胞黏附分子1和单核细胞趋化蛋白1的mRNA及蛋白表达水平分别通过RT-PCR、Western blot检测。使用Western blot检测RhoA、ROCK-1、p-MYPT及MYPT蛋白表达水平变化。结果法舒地尔显著抑制高糖诱导的THP-1与人脐静脉内皮细胞黏附,并呈剂量依赖性,其中,低浓度法舒地尔(10-6 mmol/L)干预24 h黏附减少约33.4%,高浓度法舒地尔(10-5 mmol/L)干预24 h黏附减少约42.8%(P值均0.05),干预12 h组趋势相同。法舒地尔显著减低高糖诱导的人脐静脉内皮细胞血管细胞黏附分子1及单核细胞趋化蛋白1的mRNA及蛋白表达水平,并呈时间依赖性和剂量依赖性。高糖显著增加p-MYPT/MYPT比值,而法舒地尔减弱高糖对p-MYPT/MYPT比值的影响,抑制Rho/RCOK通路激活。结论法舒地尔抑制高糖诱导的THP-1与人脐静脉内皮细胞黏附,减低高糖诱导的人脐静脉内皮细胞血管细胞黏附分子1和单核细胞趋化蛋白1的表达,减少高糖诱导的Rho/RCOK通路激活,提示法舒地尔可能成为新的糖尿病大血管病变治疗药物。     

Double-edged effects and mechanisms of Zn2+ microenvironments on osteogenic activity of BMSCs: osteogenic differentiation or apoptosis

Zinc-incorporated biomaterials show promoting effects on osteogenesis; however, excessive zinc ions lead to cytotoxic reactions and also have other adverse effects. Therefore, the double-edged effects of Zn²⁺ microenvironments on osteogenesis may become critical issues for new material development. This study systematically investigated the bidirectional influences of diverse Zn²⁺ microenvironments on the cell adhesion, proliferation, osteogenic differentiation and apoptosis of rBMSCs. Furthermore, the mechanisms of zinc-induced osteogenic differentiation of rBMSCs and of cell apoptosis induced by high concentration of Zn²⁺ were both discussed in detail. The results indicated that the Zn²⁺ microenvironments of 2 μg mL⁻¹ and 5 μg mL⁻¹ effectively improved the initial adhesion and proliferation of rBMSCs, while that of 15 μg mL⁻¹ had exactly the opposite effect. More importantly, the suitable Zn²⁺ microenvironments (2 μg mL⁻¹ and 5 μg mL⁻¹) moderately increased the intracellular Zn²⁺ concentration by regulating zinc transportation, and then activated the MAPK/ERK signaling pathway to induce the osteogenic differentiation of rBMSCs. In contrast, the high Zn²⁺ concentration (15 μg mL⁻¹) not only inhibited the osteogenic differentiation of rBMSCs by damaging intracellular zinc homeostasis, but also induced rBMSC apoptosis by enhancing intracellular ROS generation. The current study clarified the double-edged effects of Zn²⁺ microenvironments on the osteogenic properties of rBMSCs and the related mechanisms, and may provide valuable guidance for optimizing the design of zinc-doped biomaterials and zinc-based alloys.

Dual-directional regulation of diverse Zn²⁺ microenvironments on osteogenic activity of BMSCs plays important roles in the design of zinc-containing biomaterials.     

A comparative biomechanical study of proximal femoral nail (InterTAN) and proximal femoral nail antirotation for intertrochanteric fractures

Purpose

The purpose of this study was to compare the biomechanical strength of the cephalomedullary nail InterTAN in cases of intertrochanteric fractures with the commonly used PFNA.

Methods

Sixteen fresh specimens of the proximal femur were used as intertrochanteric fracture models and were fixed using two fixation devices: the new proximal femoral nail (InterTAN) and proximal femoral nail antirotation (PFNA). An intertrochanteric fracture was created in composite bone models. Each specimen was loaded to simulate single leg stance while stiffness, migration (cut out), compressive force across the fracture site, and distal fragment rotation were monitored. The different internal fixation methods were tested by an experimental press analysis.

Results

Results of tests for femoral strength, stiffness, stability, and bearing capacity demonstrated that the biomechanical function of InterTAN was better than that of PFNA (P < 0.05). Compared with the PFNA nail, InterTAN showed increased strength, stiffness, and resistance torque of 30 %, 15 %, and 27 %, respectively.

Conclusion

Comparison of the treatment of intertrochanteric fractures with InterTAN and PFNA internal fixation showed that the InterTAN yielded improvement relative to the PFNA. InterTAN has a firmer and biomechanically superior performance and is therefore an ideal internal fixation method for treating intertrochanteric fractures. Additional research in osteopenic bone is necessary to comprehensively characterize the effects of the design enhancements of these two implants.     

上海市静安区2017—2019年集体机构学生水痘疫苗应急接种效果评估

目的 了解集体机构学生水痘减毒活疫苗(varicella attenuated live vaccine, VarV)的接种情况,为分析疫苗接种的保护效果提供依据。方法 将2017—2019年静安区所有发生水痘疫情并开展应急接种的集体机构作为研究场所,将其涉及到的发病班级内所有学生(6 473名)作为研究对象,收集水痘发病信息、VarV接种情况,分析VarV的保护效果(vaccine effectiveness, VE)及不同状态下应急接种的效果。结果 学生无免疫史的比例逐年下降,2017年为7.5%、2018年为7.2%、2019年为4.9%;病例中VarV既往免疫史的比例(90.0%)低于非病例(93.5%),差异有统计学意义(χ²=6.53,P<0.05);病例中VarV应急接种的比例(8.3%)低于非病例(44.1%),差异有统计学意义(χ²=179.06,P<0.01);续发病例中VarV应急接种的比例(28.6%)低于非病例(44.1%),差异有统计学意义(χ²=9.44,P<0.01);无...