不同来源间充质干细胞生物学特征的比较

目的:比较脐静脉、成人骨髓及胎儿骨髓3种不同来源的间充质干细胞体外生长特性及分化潜能。方法:①实验于2004-01/2006-06在苏州大学附属第二医院中心实验室完成。孕39～40周健康产妇正常分娩2h的脐带以及3～4月龄流产胎儿均由苏州大学附属第二医院妇产科提供,产妇及其家属均知情同意。正常成人骨髓由苏州大学附属第二医院血液科研究生捐献。本实验经医学伦理委员会批准。②脐带用含青、链霉素的磷酸盐缓冲液冲净静脉腔内残血,夹闭两端,经37℃预热的1.5g/L胶原酶消化,重悬于DMEM-LG(含体积分数为0.1的新生牛血清、20mmol/LHEPES、2mmol/L L-谷氨酰胺、1mmol/L丙酮酸钠),以108L-1密度接种于25cm2培养瓶常规培养,48h后弃上清,以后每两三天半量换液,3周后用5g/L胰酶消化传代。③抽取正常成人骨髓5～10mL,ficoll分离单个核细胞,收取白雾层及以上部分细胞,采用上述培养基按相同条件进行培养,约14～18d胰酶消化传代。④取流产胎儿,无菌条件下分离股骨,冲洗干净后采用两种方法分离间充质干细胞:直接将胎骨剪成约1mm3大小的碎片,磷酸盐缓冲液洗涤后加入少量上述培养基,置10cm培养皿培养;剪去股骨两端后,用上述培养基冲出骨髓腔内细胞,直接培养。⑤观察连续传代对3种不同来源间充质干细胞增殖的影响;免疫荧光及免疫组化分析所得细胞的表型;观察3种不同来源间充质干细胞在诱导培养条件下向成骨及成脂细胞分化的潜能。结果:①不同来源间充质干细胞的体外增殖特性:脐带、成人及胎儿骨髓内均存在间充质干细胞,且细胞形态相似。成人骨髓间充质干细胞的体外增殖能力较差,传至10～12代基本失去增殖能力。脐静脉间充质干细胞的增殖能力强于成人骨髓间充质干细胞,可体外连续传代15～18次。而胎儿来源的间充质干细胞增殖能力及体外传代更新能力均明显强于其他两种间充质干细胞,传至20代时基本保持原有的特性。②不同来源间充质干细胞免疫表型:3种间充质干细胞均高表达CD29、CD44、CD54及HLA-ABC分子,成人骨髓源间充质干细胞还表达中等量的CD106及少量HLA-DR。3种间充质干细胞均不表达造血细胞标志CD34和CD45,其中脐静脉来源的间充质干细胞αSMA呈阳性,vWF呈阴性。③不同来源间充质干细胞的分化潜能:在成脂或成骨条件培养基中,3种间充质干细胞均可向脂肪及成骨细胞分化,油红O及von Kossa染色呈阳性。结论:①脐带、成人及胎儿骨髓内均存在数量不等的间充质干细胞,其形态、生长特性及表面标志具有相似性。②脐静脉源间充质干细胞的增殖能力优于骨髓间充质干细胞,尽管略弱于胎源性间充质干细胞,但其来源广泛、分离方便、间充质干细胞得率高,且没有伦理限制,是一种较好的间充质干细胞来源。     

肾移植术后乙型肝炎病毒拉米夫定耐药的治疗

目的:观察肾移植术后乙型肝炎病毒患者发生拉米夫定耐药后,应用新一代核苷类抗乙型肝炎病毒药物阿德福韦和恩替卡韦的治疗效果。方法:选择2001-05/2006-09于南方医科大学南方医院器官移植科就诊的乙型肝炎病毒感染并发生病毒多聚酶催化域YMDD基序变异,对拉米夫定耐药的肾移植患者4例,患者均知情同意。定期复查血清丙氨酸转氨酶、天冬氨酸转氨酶、总胆红素、乙型肝炎病毒DNA定量及乙型肝炎病毒YMDD变异情况,先后采用拉米夫定、阿德福韦及恩替卡韦进行治疗,并观察其治疗效果。结果:①4例患者分别随访16,26,63,67个月,移植肾功能良好。②4例患者分别在服用拉米夫定14,24,51和62个月(术后12个月)时出现乙型肝炎病毒YMDD变异,乙型肝炎病毒DNA升高至105～109拷贝/mL,肝功能异常。2例加用阿德福韦3个月后撤除拉米夫定,单用阿德福韦治疗,乙型肝炎病毒DNA均降为104拷贝/mL,肝功能正常,其中1例单用阿德福韦9个月后乙型肝炎病毒YMDD变异转阴,另1例单用阿德福韦2个月,乙型肝炎病毒YMDD变异仍为阳性;2例停用拉米夫定,直接换为恩替卡韦,其中1例2个月后肝功能正常,乙型肝炎病毒DNA阴性,乙型肝炎病毒YMDD变异阴性,另1例服药2个月后肝功能正常,乙型肝炎病毒DNA降为104拷贝/mL,乙型肝炎病毒YMDD变异仍为阳性。结论:新型抗乙型肝炎病毒药物阿德福韦和恩替卡韦可有效抑制拉米夫定耐药的乙型肝炎病毒复制,有利于乙型肝炎病毒阳性肾移植患者长期存活。     

贲门失弛缓症术后并发食管旁疝致胃底绞窄坏死1例

介绍1例贲门失弛缓症Heller术后16 a并发食管旁疝致胃底绞窄坏死的病例．报告本例患者的详细病历资料和诊治经过．患者起病5 d后剖胸探查,发现胃底疝入左侧胸腔并绞窄坏死,行近端胃大部切除,修复食管裂孔．术后随访1 a无复发．食管旁疝发生嵌顿时,应立即插入胃管减压．如减压不成功或症状不改善,应急诊手术探查．     

颈外动脉栓塞用顺铂白蛋白微球的研究

用乳化化学交联法制备出适合于颌面部鳞癌殒外动脉栓塞用顺铂白蛋白微球;外观呈黄色粉末状,收率80±5%,显微观察呈圆球体,平场粒径56.3μm:药物含量为14.02～14.2%,包封率97.08～97.95%。对其体外释药、灭菌、稳定性及分散溶媒的处方进行了探讨。通过动物实验表明该微球可以达到理想的栓塞效果,并保证能在局部组织停留,有利于提高抗癌药物的疗效,降低毒副作用。     

用二维核磁共振法研究肿足蕨碱的结构

从金星蕨科植物山东肿足蕨(Hypodematium sinense Iwatsuki)的全草分得一种新化合物,通过¹H-¹H COSY谱,¹H-¹³C COSY谱和远程¹H-¹³C COSY谱确定其结构是一种具有苯基取代苯并氮杂环辛四烯新型骨架的生物碱,命名为肿足蕨碱(hypodematine)(Ⅰ)。     

Impact of home carpets on childhood lead intervention study

Blood lead data for a childhood lead exposure study have been reanalyzed to examine the impact of carpets on the effectiveness of a cleaning intervention in 39 New Jersey urban houses. All eligible houses in the study were classified as carpeted and uncarpeted depending on the number of rooms that were carpeted. The cleaning protocol was associated with a significant reduction in the blood lead concentrations for the uncarpeted homes (P = 0.004), whereas no significant change was found for the carpeted homes (P = 0.566). We also completed correlation analyses between the number of cleaning visits and the percentage reduction in blood lead for the carpeted/uncarpeted houses. There was a significant correlation (r = 0.67) between the number of cleanings and blood lead reduction for the uncarpeted homes, but no correlation (r = 0.04) for the carpeted homes. In a multiple regression model that took confounding variables into account, the carpet status (carpeted or uncarpeted) remained a factor of the effect of cleaning on blood lead (P = 0.05). We conclude that the presence of contaminated carpets inhibits the effectiveness of home cleaning despite a high-efficiency particulate air filtered vacuum protocol that removes a substantial amount of lead dust.     

The effects of jet fuel on immune cells of fuel system maintenance workers

Jet fuel is a common occupational exposure among commercial and military maintenance workers. JP-8 jet fuel, a military formulation, has shown immunotoxic effects in mice, but little data exist for humans. The aim of this cross-sectional study was to determine whether immune cell counts in the peripheral blood were altered among tank entry workers at three Air Force bases. After adjusting for covariates, fuel system maintenance personnel (n = 45) were found to have significantly higher counts of white blood cells (P = 0.01), neutrophils (P = 0.05), and monocytes (P = 0.02) when compared with a low-exposure group (n = 78), but no differences were noted in the numbers of total lymphocytes, T-cells, T-helper cells, T-suppressor cells, natural killer cells, and B-cells. Investigations are needed to evaluate the functional ability of these cells to produce lymphokines and cytokines and modulate the immune system.