Synergistic effects of Nell-1 and BMP-2 on the osteogenic differentiation of myoblasts.

Osteogenesis is synergistically enhanced by the combined effect of complimentary factors. This study showed that Nell-1 and BMP-2 synergistically enhanced osteogenic differentiation of myoblasts and phosphorylated the JNK MAPK pathway. The findings are important because of the osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of coordinated BMP-2 and Nell-1 delivery. INTRODUCTION: BMPs play an important role in the migration and proliferation of mesenchymal cells and have a unique ability to alter the differentiation of mesenchymal cells toward chondrogenic and osteogenic lineages. Signaling upstream of Cbfa1/Runx2, BMPs effects are not limited to cells of the osteoblast lineage. Thus, additional osteoblast-specific factors that could synergize with BMP-2 would be advantageous for bone regeneration procedures. NELL-1 (NEL-like molecule-1; NEL [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel growth factor believed to preferentially target cells committed to the osteochondral lineage. MATERIALS AND METHODS: C2C12 myoblasts were transduced with AdLacZ, AdNell-1, AdBMP-2, or AdNell-1+AdBMP-2 overexpression viruses. Effects were studied by cell morphology, alkaline phosphatase activity, osteopontin production, and MAPK signaling. Additionally, in a nude mouse model, viruses were injected into leg muscles, and new bone formation was examined after 2 and 8 wk. RESULTS: C2C12 myoblasts co-transduced with AdNell-1+AdBMP-2 showed a synergistic effect on osteogenic differentiation as detected by alkaline phosphatase activity and osteopontin production. Nell-1 stimulation on AdNell-1 + AdBMP-2 preconditioned C2C12 cells revealed significant activation of the non-BMP-2 associated c-Jun N-terminal kinase (JNK) MAPK signaling pathway, but not the p38 or extracellular signal-regulated kinase (ERK1/2) MAPK pathways. Importantly Nell-1 alone did not induce osteogenic differentiation of myoblasts. In a nude mouse model, injection of AdNell-1 alone stimulated no bone formation within muscle; however, injection of AdNell-1+AdBMP-2 stimulated a synergistic increase in bone formation compared with AdBMP-2 alone. CONCLUSIONS: These findings are important because of the confirmed osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of enhanced BMP-2 action with coordinated Nell-1 delivery.     

伴有齿槽嵴裂的单侧唇裂术后继发鼻畸形的修复

目的探讨伴有齿槽嵴裂的单侧唇裂术后继发鼻畸形的修复方法。方法对34例伴有齿槽嵴裂的单侧唇裂术后继发畸形的患者,在行齿槽嵴植骨的同时,行彻底的鼻整形手术。结果术后随访1~3年,植骨区成活良好,鼻畸形较整形前明显改善,接近正常外形,效果满意。结论在行齿槽嵴植骨的同时,行彻底的鼻整形手术,能够取得满意的效果,并且节省了医疗费用,缩短了治疗时间。     

基因活化材料的构建及在骨与软骨损伤中的应用

组织工程技术为关节软骨的再生带来希望，适当浓度的生长因子、合适的微环境无疑会利于这种技术的实施。近年来，生物可降解材料作为基因传送载体转染体细胞的研究正逐渐受到重视，可以利用生物材料的降解特性以及化学构成特点构建具有可控制性、安全性、靶向性的转染系统，通过靶细胞表达转移后的基因片段，可以在局部持续获得治疗性的生长因子。     

获得性纯红再障患者外周血T细胞亚群分析

目的　本研究通过分析获得性纯红再障患者外周血T细胞亚群 ,进一步探讨该病的细胞免疫发病机制。方法　用抗人CD3、CD4、CD8、IFN γ及IL 4单抗结合人外周血单个核细胞 ,流式细胞术分析单个核细胞中CD3 +、CD4+、CD8+细胞数Th1、Th2、Tc1、Tc2细胞数以及CD4+/CD8+、Th1/Th2、Tc1/Tc2比值。结果　贫血组患者 ,外周血CD3 +细胞和CD8+细胞明显增加 (P <0 .0 1) ,CD4+/CD8+比例倒置 (P <0 .0 5 ) ;Tc2细胞明显增加 (P <0 .0 5 ) ,Tc1/Tc2比值降低(P <0 .0 5 ) ,治疗后血象恢复的患者各增高的亚群细胞均有所恢复 ,接近正常。结论　在获得性纯红再障患者T细胞明显增高 ,其中主要是CD8+细胞 ,而在CD8+细胞中 ,是Tc2细胞发挥了重要作用。经治疗有效的患者 ,其增高的T细胞亚群降低 ,提示以纠正病人细胞免疫异常为主的治疗方案有益于获得性纯红再障的治疗。     

rhTPO在大肠杆菌中的表达、纯化及生物活性分析

目的：探讨人促血小板生成素(human thromlbopoietin，hTPO)在大肠杆菌中表达、分离纯化及生物学活性初步鉴定。方法：利用RT-PCR法从人胎肝细胞中扩增目的基因片段，将其定向插入pQE30表达质粒T5启动子下游的多克隆区，转化大肠杆菌M15，得到pQE30-TPO的工程菌，诱导目的蛋白表达、纯化。将表达产物给血小板减少模型小鼠尾静脉注射，观察注射后不同时间血小板量的改变。结果：经异丙基硫代-β-D-半乳糖苷(isopropylthio-β-D-galactoside IPTG)诱导培养，该工程菌可以产生单一特异性的高表达蛋白条带。将纯化后的表达蛋白注射小鼠，结果显示对实验性小鼠血小板减少症具有一定的治疗作用。结论：在大肠杆菌中成功地高效表达了重组hTPO，该产物具有促血小板生成的活性。     

利用cDNA微阵列技术筛选成年期与胚胎期睾丸差异表达基因——钙联接蛋白基因

目的 :用cDNA微阵列技术克隆和筛选成年期与胚胎期睾丸差异表达基因 ,以进行睾丸发育及精子发生的调控研究。　方法 :构建人睾丸cDNA芯片 ,分别用正常成人及胚胎睾丸的mRNA探针进行杂交 ,对成人和胚胎睾丸中差异表达的基因进行高流量的比较。　结果 :发现 1条成人睾丸高表达、胚胎低表达的基因———钙联接蛋白 (CLGN)基因。　结论 :运用cDNA微阵列方法可筛选到成年期与胚胎期睾丸差异表达基因     

某电厂25 MW煤气发电工程职业病危害因素水平调查

目的 了解该项目主要职业病危害因素的种类、分布以及浓度和强度，提出防护措施，以达到减少职业病危害因素对人体健康的影响。方法 通过职业卫生学调查和现场测试对该项目职业病危害控制效果进行评价。结果 噪声、粉尘、一氧化碳、二氧化碳及二氧化硫化学毒物合格率为100％。结论 该建设项目生产工艺与设备先进，自动化程度较高，职业卫生防护设施基本齐全，防毒、防噪和防高温效果好，是优质环保工程。     

The significance of a rapid cold hemagglutination test for detecting mycoplasma infections in children with asthma exacerbation.

BACKGROUND AND PURPOSE: Mycoplasma pneumoniae infection is a frequent cause of community-acquired respiratory infections in children and adults. However, standardized, rapid, specific methods for its diagnosis are lacking. The relationship between M. pneumoniae infection and asthma exacerbation has been recently discussed in the literature. We investigated the accuracy of rapid detection of mycoplasma infection by cold hemagglutination test compared to conventional enzyme immunoassays. The clinical characteristics of mycoplasma infection seen during emergent visits in asthmatic children were reviewed. METHODS: We retrospectively reviewed medical records of patients with asthma exacerbation visiting the Department of Pediatric Emergency, National Taiwan University Hospital, over a 12-month period. Subjects 2-18 years of age diagnosed with asthma at our outpatient clinic were included in this study. Patients with immunodeficiency, congenital anomalies, neurological diseases and irregular follow-up were excluded. RESULTS: A total of 269 children (174 males and 95 females) with a mean (+/- standard deviation) age of 6.15 +/- 3.08 years were included. The prevalence of asthma exacerbation in regular follow-up patients was 13.4%, and as many as 19.6% of cases (74/378 person-times) required hospitalization. Asthma attacks were most prevalent during December. 126 patients had both rapid cold hemagglutination testing and mycoplasma immunoglobulin M titers determined using acute blood samples drawn in the emergency room; 46 (36.5%) of these patients demonstrated mycoplasma infection. Sensitivity and specificity of the rapid cold hemagglutination test was 78.3% and 41.3%, respectively. The positive predictive value was 43.4%. Comparison of patients with or without mycoplasma infection revealed no differences in gender, age, chest X-ray findings, and most symptoms/signs and laboratory data, except that more signs of fever and auscultatory rales were seen in the non-mycoplasma infection group. CONCLUSIONS: Mycoplasma infections could be an exacerbating factor for asthma, and the rapid cold hemagglutination test should not be a guideline for prescribing macrolides in the emergency room.     

OCM入路微创全髋关节置换术的初步报告

目的介绍OCM入路微创全髋关节置换术(THA)的手术方法。方法2005年1月-2006年1月在对2具尸体、4个髋关节的OCM入路进行相关解剖学研究的基础上开展OCM入路微创THA 20例。手术从臀中肌前间隙进入切开关节囊,分段完成股骨颈截骨,使用特殊的髋臼锉和髋臼打入器安放髋臼假体;股骨侧手术时手术床后下方一半拆卸掉,患髋后伸和外旋且小腿置于消毒袋内,大转子周围关节囊广泛剥离后完成扩髓和股骨假体的安放。结果肥胖指数平均为27．4％的20例患者,皮肤切口长度平均为9．3 cm;术中平均出血130 mL,术后引流量80 mL;患者术后2-3 d下地活动。所有患者获得1-9个月(平均4．3个月)随访,15例已完全脱拐,行走正常;5例不满1个月,仍需扶拐行走。术后随访疼痛采用视觉模拟评分(VAS)由术前平均5．1分分别下降到3．6分(1个月)、1．7分(3个月)和0．8分(6个月)。发生血肿2例,X线检查见髋臼前倾过大2例,股骨假体型号偏小2例。患者髋关节功能Harris评分由术前平均45．4分提高到术后随访时平均88．4分。结论OCM入路微创THA切口小,完整保留臀中肌和关节囊,患者功能恢复快,住院时间短;它需要一个独立学习过程,并需要特殊器械的配合。