改良消蚀法制备脱细胞真皮基质微粒及其生物相容性评价

目的:利用改良消蚀法制备一种新型脱细胞真皮基质(Acellular dermal matrix,ADM)微粒,并对其相容性加以评价,为组织工程微粒皮肤的制备奠定研究基础。方法:应用机械法切除猪真皮乳头层,结合消蚀法和冻融法除去网状真皮中的所有细胞制备成ADM,将ADM搅碎成颗粒状,对其做细胞毒性实验和皮下埋藏实验检验其相容性。结果:该方法制备的ADM微粒韧性好,细胞去除完全,胶原三维稍松散但结构完整,无基底膜和乳头层。细胞毒性实验显示其基本无毒性,成纤维细胞在ADM微粒上增殖良好,皮下埋藏试验未见明显排异反应,ADM微粒能诱导血管和成纤维细胞长入。结论:用改良消蚀法制备的ADM微粒抗原性低、相容性好,可以作为组织工程微粒皮肤的支架和填充材料。     

Maslinic acid suppresses osteoclastogenesis and prevents ovariectomy‐induced bone loss by regulating RANKL‐mediated NF‐κB and MAPK signaling pathways

Activation of NF‐κB and MAPK/activator protein 1 (AP‐1) signaling pathways by receptor activator NF‐κB ligand (RANKL) is essential for osteoclast activity. Targeting NF‐κB and MAPK/AP‐1 signaling to modulate osteoclast activity has been a promising strategy for osteoclast‐related diseases. In this study we examined the effects of maslinic acid (MA), a pentacyclic triterpene acid that is widely present in dietary plants, on RANKL‐induced osteoclastogenesis, osteoclast function, and signaling pathways by in vitro and in vivo assay systems. In mouse bone marrow monocytes (BMMs) and RAW264.7 cells, MA inhibited RANKL‐induced osteoclastogenesis in a dose‐dependent manner within nongrowth inhibitory concentration, and MA decreased osteoclastogenesis‐related marker gene expression, including TRACP, MMP9, c‐Src, CTR, and cathepsin K. Specifically, MA suppressed osteoclastogenesis and actin ring formation at early stage. In ovariectomized mice, administration of MA prevented ovariectomy‐induced bone loss by inhibiting osteoclast activity. At molecular levels, MA abrogated the phosphorylation of MAPKs and AP‐1 activity, inhibited the IκBα phosphorylation and degradation, blocked NF‐κB/p65 phosphorylation, nuclear translocation, and DNA‐binding activity by downregulating RANK expression and blocking RANK interaction with TRAF6. Together our data demonstrate that MA suppresses RANKL‐induced osteoclastogenesis through NF‐κB and MAPK/AP‐1 signaling pathways and that MA is a promising agent in the treatment of osteoclast‐related diseases such as osteoporosis. © 2011 American Society for Bone and Mineral Research.     

亚甲蓝切缘封闭在环状混合痔手术中的应用

为探讨亚甲蓝切缘封闭在环状混合痔手术中的临床应用价值,将72例手术治疗的环状混合痔患者随机分为治疗组和对照组,各36例,对照组采用保留齿状线、分段外切内扎术治疗,治疗组在对照组手术的基础上加行亚甲蓝切缘封闭注射。观察两组治愈率、创面愈合时间、术后肛门疼痛、肛缘水肿、术后早期排尿及排便功能等情况。结果显示,在治愈率方面,两组差异无统计学意义,P〉0．05;但在创面愈合时间、术后肛门疼痛、肛缘水肿、排尿困难及排便困难等方面,治疗组明显优于对照组,P〈0．05。结果表明,在环状混合痔手术中加行亚甲蓝切缘封闭注射,可以显著减少术后并发症的发生,减轻患者痛苦,缩短创面愈合时间。     

Structural and molecular analyses of bone bridge formation within the growth plate injury site and cartilage degeneration at the adjacent uninjured area

Injury to the growth plate is common and yet the injured cartilage is often repaired with undesirable bony tissue, leading to bone growth defects in children. Using a rat tibial growth plate injury model, our previous studies have shown sequential inflammatory, fibrogenic, osteogenic and bone maturation responses involved in the bony repair. However, it remains unclear whether there is progressive accumulation of bone within the injury site and any potential degenerative changes at the adjacent non-injured area of the growth plate. This study examined effects of growth plate injury on the structure, composition and some cellular and molecular changes at the injury site and adjacent uninjured area. Micro-CT analysis revealed that while the bone volume within the injury site at day 14 was small, the bone bridge was considerably larger at the injury site by 60 days post-injury. Interestingly, formation of bone bridges in the adjacent uninjured area was detected in 60% of injured animals at day 60. Immunohistochemical analyses revealed reduced chondrocyte proliferation (PCNA labelling) but increased apoptosis (nick translation labelling) in the adjacent uninjured area. RT-PCR analysis on adjacent uninjured growth plate tissue found increased expression of osteocalcin at day 60, differential expression of apoptosis-regulatory genes and alterations in genes associated with chondrocyte proliferation/differentiation, including Sox9 and IGF-I. Therefore, this study has demonstrated progressive changes in the structure/composition of the injury site and adjacent uninjured area and identified cellular and molecular alterations or degeneration in adjacent uninjured growth plate in response to injury.     

The role of nitric oxide in the mechanical repression of RANKL in bone stromal cells

Both mechanical loading and nitric oxide (NO) have positive influences on bone mass. NO production is induced by mechanical strain via upregulation of eNOS mRNA and protein, the predominant NOS in adult bone. At the same time, strain causes decreased expression of RANKL, a factor critical for osteoclastogenesis. In this study, we harvested primary stromal cells from wild-type (WT) and eNOS(-/-) mice to test whether induction of NO by mechanical strain was necessary for transducing mechanical inhibition of RANKL. We found that strain inhibition of RANKL expression was prevented by NOS inhibitors (L-NAME and L-NMMA) in WT stromal cells. Surprisingly, stromal cells from eNOS(-/-) mice showed significant mechanical repression of RANKL expression (p<0.05). Mechanical strain still increased NO production in the absence of eNOS, and was abolished by SMTC, a specific nNOS inhibitor. nNOS mRNA and protein expression were increased by strain in eNOS(-/-) but not in WT cells, revealing that nNOS was mechanically sensitive. When NO synthesis was blocked with either SMTC or siRNA targeting nNOS in eNOS(-/-) cells however, strain still was able to suppress RANKL expression by 34%. This indicated that strain suppression of RANKL can also occur through non-NO dependent pathways. While our results confirm the importance of NO in the mechanical control of skeletal remodeling, they also suggest alternative signaling pathways by which mechanical force can produce anti-catabolic effects on the skeleton.     

OPCAB与CABG术后患者ICU监护的对比观察

目的探讨非体外循环心脏跳动下冠状动脉搭桥术（OPCAB）与体外循环下冠状动脉搭桥术（CCABG）术后ICU监护工作特点及临床意义。方法随机抽取甲组（n=32）OPCAB组;乙组（n=48）CABG组。通过对两组病人术后ICU内监护时间、辅助呼吸时间、住院总天数、术后引流量及术后并发症等方面作统计学处理和对比分析。结果两组患者术后ICU内监护时间、辅助呼吸时间、住院总天数、术后引流量均有显著性差异（P〈0．05）。结论非体外循环心脏跳动下冠状动脉搭桥术心功能稳定,并发症少,明显减少了药品使用和护理工作量,能为监护室的排班提供合理依据。     

肱骨髁上骨折并发症98例临床分析

目的：探讨肱骨髁上骨折并发症发生率,发生原因及防治对策。方法：对302例肱骨髁上折伴合并症的98例进行临床分析,结果：血管损伤54例（55．1％）,神经损伤23例（23．4％）,感染4例（4．1％）,肘内翻14例（14．3％）,肘外翻3例（3．1％）,结论：血管损伤多为骨折断刺激和压迫肱动脉,神经损伤由于神经挫伤,牵拉和压迫引起,感染系清创不彻底,肘内翻大部分系尺偏型骨折,肘外翻由于骨折矫正不当所致。合理的复位,良好的固定及正确的X线评价是防治并发症的重要的措施。     

安信医用抗菌贴加速慢性难愈合创面愈合

目的 观察安信医用抗菌贴对慢性难愈合创面（溃疡）的促修复作用并探讨其修复机制。方法 34例共44个慢性难愈合创面,其中创伤性溃疡15例（23个创面）,压迫性溃疡9例（11个创面）,糖尿病溃疡5例,放射性溃疡5例。所有创面经清创后用安信医用抗菌贴外敷于创面,每2－3天更换一次。结果 所有经安信医用抗菌贴治疗的创面都明显愈合,其中2周内愈合26个创面,3周内愈合7个创面,4周内愈合9个创面,超过4周愈合2个创面。4周内总愈合率炎95．5％。结论 安信医用抗菌贴可以显著地加速慢性难愈合创面的愈合,其机制为广谱速效杀菌,改善局部微循环,有效激活并促进组织细胞生长。     

降糖通脉片对人肾小球系膜细胞及细胞外基质影响的实验研究

目的：探讨降糖通脉片对人肾小球系膜细胞（MC）及其细胞外基质（ECM）的影响。方法;采用血清药理学方法和体外人肾小球系膜细胞培养技术,观察具有清热化瘀,滋阴补气作用的中药降糖通脉片对MC增殖及其ECM成分的影响。结果：降糖通脉片具有抑制MC增殖及ECM成分中纤维连接蛋白（FN）,层粘连蛋白（LN）和IV型胶原（ColIV)的作用,该抑制作用具有一定的量效关系。结论：MC是降糖通脉片发挥治疗作用的 重要靶细胞,抑制MC增殖和ECM的产生可能是该方延缓肾小球硬化的重要机制之一。     

力学刺激促进骨髓基质干细胞体外软骨分化

目的探讨离心力刺激对猪骨髓基质干细胞(BMSCs)体外成软骨分化的作用,以及对三维支架上构建组织工程化软骨的影响,明确力学刺激与细胞分化及组织形成的关系,为体外软骨构建提供适当参数。方法抽取8周龄猪髂嵴骨髓,应用贴壁法分选单个核细胞,体外培养扩增后获得第2代BMSCs,以5.0×107/cm3的细胞密度接种到聚羟基乙酸(PGA)制成的圆柱形三维支架上,7d后分成4组,在不同的力学条件及诱导条件下培养。8周后取材,行相关检测。结果力学诱导组形成的组织呈白色,细腻光泽,形状规则,体积无明显改变,有良好的弹性和硬度,并具有典型的软骨陷窝结构和大量软骨特异性细胞外基质,Ⅱ型胶原及丰富的聚合蛋白多糖(GAG)成分。GAG含量为(6.0±1.2)mg/g,抗压强度为(2.2±0.8)kPa,弹性模量为(7.4±1.6)kPa。各项指标均明显优于其他各组。结论力学刺激有利于促进BMSCs成软骨分化,并在三维支架材料上构建组织工程化软骨。