Use of human perivascular stem cells for bone regeneration

Human perivascular stem cells (PSCs) can be isolated in sufficient numbers from multiple tissues for purposes of skeletal tissue engineering. PSCs are a FACS-sorted population of 'pericytes' (CD146+CD34-CD45-) and 'adventitial cells' (CD146-CD34+CD45-), each of which we have previously reported to have properties of mesenchymal stem cells. PSCs, like MSCs, are able to undergo osteogenic differentiation, as well as secrete pro-osteogenic cytokines. In the present protocol, we demonstrate the osteogenicity of PSCs in several animal models including a muscle pouch implantation in SCID (severe combined immunodeficient) mice, a SCID mouse calvarial defect and a femoral segmental defect (FSD) in athymic rats. The thigh muscle pouch model is used to assess ectopic bone formation. Calvarial defects are centered on the parietal bone and are standardly 4 mm in diameter (critically sized). FSDs are bicortical and are stabilized with a polyethylene bar and K-wires. The FSD described is also a critical size defect, which does not significantly heal on its own. In contrast, if stem cells or growth factors are added to the defect site, significant bone regeneration can be appreciated. The overall goal of PSC xenografting is to demonstrate the osteogenic capability of this cell type in both ectopic and orthotopic bone regeneration models.     

PKP 在治疗多节段胸腰椎骨质疏松压缩性骨折方面的应用

目的:探讨经皮椎体后凸成形术(PKP)治疗多节段骨质疏松性椎体压缩性骨折(OVCF)的疗效和安全性。方法:应用PKP治疗37例共112节胸腰椎多节段骨质疏松性椎体压缩骨折,分析患者术前、术中、术后的临床及影像学资料,采用模拟视觉评分(VAS)及Oswesty功能障碍指数(ODI)评价术前、术后疼痛缓解及日常活动功能恢复情况。结果:13例一次手术完成1节椎体,12例一次手术完成2～3节段椎体,12例两次手术完成3～4个节段椎体。1例术中出现一过性血压降低和呛咳。VAS评分术前为(8.55±1.22)分,术后1周为(2.12±1.09)分,术后3个月为(2.01±1.07)分;ODI值术前为83.02±11.14,术后1周为25.23±7.17,术后3个月为27.45±9.67,疼痛缓解及日常活动功能恢复明显。结论:初步的临床结果显示PKP是多节段骨质疏松性椎体压缩性骨折的有效治疗方法,单椎体信号改变者治疗效果好于多椎体信号改变者。多椎体信号改变者只选择第一责任椎的单节段PKP可能获得更好的效果;多节段患者同时选择第一和第二责任椎一次完成PKP术效果可能好于分次完成。一次治疗多椎体病变更为经济、适用。     

关节镜下逆行交锁髓内钉治疗股骨远端骨折36例分析

目的:探讨关节镜下逆行交锁髓内钉治疗股骨远端骨折的疗效、特点及其必要性.方法:采用关节镜下逆行交锁髓内钉进行手术治疗36例股骨远端骨折.结果:36例中膝关节内病损17例,经随访6个月至2年,平均10月,膝关节活动度90°～140°,平均125°.骨折愈合时间3～9个月,平均6个月.结论:关节镜引导下逆行交锁髓内钉治疗股骨远端骨折,同时对膝关节内损伤或病变明确诊断并进行相应处理,避免漏诊,手术时间短,最大限度地保留了膝关节的解剖与功能的完整性,对膝关节损伤小,值得推广.     

An assessment of impact strength of the mandible

In this study, an animal biomechanical study was performed to investigate the absorbed energy and impact strength of the mandible in relation to specimen position. Four regions of mandibles were loaded as complete pieces and gripped by the jaw of an Izod impact tester. All tests were carried out wet using the Izod impact test under two different impact loading directions, lateral and ventral.Absorbed energy and impact strength in kilojoules per square meter of specimen area were determined for each specimen. Under lateral impact loading, the absorbed energy was lowest for the anterior section due to the mental foramen's notch effect. The premolar region demonstrated more absorbed energy per unit area, or impact strength, than any other region. However, due to its small cross-sectional area, the premolar region also absorbs less impact energy.Under ventral impact loading conditions, anterior region absorbed twice as much impact energy than under lateral loading conditions. Premolar region absorbed the same impact energy under both lateral and ventral loading. Interestingly, mandibular angle under ventral loading absorbed five times more impact energy than under lateral loading. This behaviour is considered to be a mechanical adaptation to the actual loading of the mandible in vivo.     

股骨头缺血坏死介入治疗的临床应用研究

目的:探讨介入治疗股骨头缺血坏死的临床应用价值。方法:采用Seldinger技术对28例患者行超选择股骨头供血动脉插管,动脉造影、溶通治疗。结果:28例患者治疗后髋部疼痛及关节功能障碍均有不同程度的减轻及改善,有效率96.4%;治疗后病变区血管分支增多、增粗;影像随访显示股骨头骨质不同程度修复。结论:介入治疗具有创伤小、并发症低、血管再通率高、临床症状改善明显的优势,能有效的改善股骨头的局部血液循环和髋关节的疼痛、活动功能,应大力推广。     

Opposite Contributions of Trunk and Leg Fat Mass with Plasma Lipase Activities: The Hoorn Study

Objective: Lipoprotein lipase (LPL) and hepatic lipase (HL) are essential in hydrolysis of triglyceride‐rich lipoproteins. LPL activity is negatively, whereas HL activity is positively, associated with total body fat. We determined the associations of trunk and leg fat mass with plasma LPL and HL activities in a cross‐sectional study. Research Methods and Procedures: LPL and HL activities were determined in post‐heparin plasma in a sample of 197 men and 209 women, 60 to 87 years of age. A total body DXA scan was performed to determine trunk and leg fat mass. Results: In women, but not in men, trunk fat mass was negatively associated with LPL activity, whereas leg fat mass was positively associated, after mutual adjustment and adjustment for age. Standardized βs (95% confidence interval) for trunk and leg fat mass were ?0.24 (?0.41; ?0.08) and 0.14 (?0.02; 0.31), respectively (interaction by sex, p = 0.03). Larger trunk fat mass was associated with higher HL activity in men [0.48 (0.28; 0.68)] and women [0.40 (0.24; 0.56)]. A negative association of leg fat mass and HL activity was observed in men, although not statistically significant [?0.13 (?0.33; 0.06)], and in women [?0.28 (?0.38; ?0.18)]. Discussion: Abdominal fat is associated with unfavorable and femoral fat with favorable LPL and HL activities in plasma.     

Therapeutic effects of electromagnetic fields in the stimulation of connective tissue repair

The therapeutic effects of electric and magnetic fields have been studied largely for their promotion of connective tissue repair. The most widely studied application concerns bone repair and deals with acceleration of the healing of fresh fractures, delayed and non-unions, incorporation of bone grafts, osteoporosis, and osteonecrosis. More recently the effects of these fields upon the repair of cartilage and soft fibrous tissues have been described. In all these experimental systems and clinical applications an acceleration of extracellular matrix synthesis and tissue healing has been observed. A degree of specificity, in terms of the parameters of applied energy and biological response, is hypothesized.     

人工髋关节置换术中股骨假体周围骨折的影响因素回归分析及其相关性

目的:研究人工髋关节置换术中股骨假体周围骨折的影响因素及其相关性,为人工髋关节置换术中股骨假体周围骨折的预防和诊治提供科学依据。方法:选取本院2012年11月至2013年9月施行髋关节置换手术的患者780例,搜集各研究对象的一般资料(年龄、性别等)以及随访观察其髋关节置换手术后股骨假体周围骨折的发生情况,把股骨假体周围骨折的发生情况与性别、年龄、固定类型等因素进行Logistic回归分析。结果:780例施行髋关节置换手术的患者中,有52例患者术后出现股骨假体周围骨折,总发生率为6.7%;其中A型31例,B型18例(B1型6例,B2型7例,B3型5例),C型3例。女性的发生率(8.5%)高于男性(4.7%),老年患者中股骨假体周围骨折的发生率最高(10.1%),生物型假体固定者的发生率(8.7%)高于骨水泥型假体固定者(3.8%),人工髋关节翻修术中股骨假体周围骨折的发生率最高(11.4%),股骨假体周围骨折发生的危险因素为女性、高龄、使用生物型假体固定,OR值分别为5.301、3.675和2.336。结论:人工髋关节置换术中的危险因素为女性、高龄、使用生物型假体固定,临床医生应在术前对行人工髋关节置换术手术者进行充分的评估,制定合理的手术方案及选择合适的固定方式。     

Influence of physical activity on tibial bone material properties in laying hens

Laying hens develop a type of osteoporosis that arises from a loss of structural bone, resulting in high incidence of fractures. In this study, a comparison of bone material properties was made for lines of hens created by divergent selection to have high and low bone strength and housed in either individual cages, with restricted mobility, or in an aviary system, with opportunity for increased mobility. Improvement of bone biomechanics in the high line hens and in aviary housing was mainly due to increased bone mass, thicker cortical bone and more medullary bone. However, bone material properties such as cortical and medullary bone mineral composition and crystallinity as well as collagen maturity did not differ between lines. However, bone material properties of birds from the different type of housing were markedly different. The cortical bone in aviary birds had a lower degree of mineralization and bone mineral was less mature and less organized than in caged birds. These differences can be explained by increased bone turnover rates due to the higher physical activity of aviary birds that stimulates bone formation and bone remodeling. Multivariate statistical analyses shows that both cortical and medullary bone contribute to breaking strengthThe cortical thickness was the single most important contributor while its degree of mineralization and porosity had a smaller contribution. Bone properties had poorer correlations with mechanical properties in cage birds than in aviary birds presumably due to the greater number of structural defects of cortical bone in cage birds.     

SL-R柄人工股骨头置换术与股骨近端防旋髓内钉治疗老年不稳定型骨质疏松性股骨粗隆间骨折的疗效比较研究

目的:探讨股骨近端防旋髓内钉、SL-R柄人工股骨头置换术两种术式治疗老年不稳定型骨质疏松性股骨粗隆间骨折的应用效果。方法:选取2015年1月-2017年6月间于河北医科大学附属秦皇岛市第一医院行手术治疗的老年不稳定型骨质疏松性股骨粗隆间骨折患者98例,以数表法将患者随机均分为对照组(n=49)和观察组(n=49)。其中对照组采用股骨近端防旋髓内钉,观察组采用SL-R柄人工股骨头置换术。比较两组患者临床各项指标、手术前后髋关节功能评分以及术后并发症发生情况。结果:观察组手术时间、术中失血量均高于对照组,但住院时间、开始负重时间则低于对照组(P0.05)。观察组术后并发症发生率为4.08%(2/49),低于对照组的18.37%(9/49)(P0.05)。术后1个月、3个月时患者髋关节各项评分相比术前均有升高,术后3个月的各项评分高于术后1个月(P0.05);观察组术后1个月、3个月各项评分均高于对照组(P0.05)。结论:在老年不稳定型骨质疏松性股骨粗隆间骨折患者治疗过程当中,采用SL-R柄人工股骨头置换术可减少住院时间,疗效确切,无严重并发症,且可改善髋关节各项功能评分。