种子细胞双相接种技术促进组织工程骨体外成熟的研究

目的 比较观察双相接种法和静置接种法构建组织工程骨对种子细胞增殖、分化和成骨表达的影响。方法 取健康志愿者骨髓，密度梯度离心法分离骨髓间充质干细胞并进行体外扩增、诱导分化，然后应用双相接种法和静置接种法与脱钙骨基质（DBM）复合构建组织工程骨，体外培养3周，用倒置显微镜、扫描电镜观察细胞密度、形态及基质分泌情况，并在不同时相点测定组织块中DNA含量、碱性磷酸酶（ALP）活性及钙含量变化。结果 倒置显微镜下双相接种法构建的组织块可见大量具有一定折光性的梭形细胞存在于胶原基质中。扫描电镜见双相接种法构建的组织块切面较平坦，孔隙较小，细胞包埋在胶原中，而静置接种法构建的组织块可见细胞、细胞外基质较少。在体外培养过程中，双相接种法组织块中细胞的DNA含量、ALP活性均高于静置接种法，钙含量在培养2周后高于静置接种法。结论 双相接种法是一种高效的组织工程骨构建方法，有利于提高接种效率和促进组织工程骨的体外成熟。     

Fas系统参与介导烧伤后心肌细胞凋亡及牛磺酸的影响

目的观察Fas系统在烧伤后心肌细胞凋亡中的作用及牛磺酸的影响。方法选健康Wistar大鼠,随机分成对照组(Sham)、烧伤组(造成40%TBSAⅢ度烧伤)和牛磺酸保护组(烫伤后即刻腹腔注射牛磺酸400 mg/kg)。用原位末端标记(TUNEL)法检测凋亡细胞,RT-PCR检测Fas mRNA表达,免疫组化检测Fas/FasL和Caspase-8/3蛋白表达和荧光法分析Caspase-3活性。结果烧伤组大鼠伤后6 h和24 h心肌细胞凋亡指数分别为8.96±2.10和18.67±2.48,较对照组(0.92±0.34)有显著性升高,Fas蛋白阳性表达指数分别为13.51±1.56和14.55±1.89,也显著性高于对照组(2.46±0.75);Caspase-3活性分别为1.38±0.16和1.96±0.71,较对照组(0.35±0.06)有显著性差异。烧伤组凋亡指数与Fas表达之间有良好的相关性(r=0.86)。牛磺酸保护组细胞凋亡指数为2.14±0.68,Fas蛋白表达为3.71±0.82,Fas mRNA表达为0.17±0.03,Caspase-3活性为0.88±0.16,较烧伤组均有显著性降低。结论Fas系统参与了介导烧伤后心肌细胞凋亡,牛磺酸对烧伤后心肌细胞Fas表达及其信号转导有较好的拮抗作用。     

细胞移植的人嗅鞘细胞培养方法的研究

目的探讨适用于细胞移植的人嗅鞘细胞（OECs）分离与培养的方法。方法无菌条件下取自愿捐献孕5个月流产胎儿的完整嗅球进行嗅鞘细胞提取分离、纯化，并对嗅鞘细胞进行免疫组化染色及纯度检测，观察其形态学特点，检测其免疫组化染色的阳性率。结果本方法分离、培养的嗅鞘细胞大多呈三角形、梭形，有些突起较长，生长活跃，增殖迅速，P75、胶质纤维酸性蛋白（GFAP）免疫组化染色呈阳性，嗅鞘细胞阳性率为95．3％。结论该方法简便易行且不影响细胞功能，适用于细胞移植的研究。     

保元排毒丸对顺铂引起的LLC-PK1细胞凋亡干预作用研究

目的：观察保元排毒丸对顺铂（DDP）所致猪肾小管上皮细胞（LLCPK1）凋亡的影响。方法：LLC-PK1细胞分三组培养，空白血清组采用不舍药血清进行培养，模型组分别以10和6μg／mL不同浓度的DDP进行培养，模型＋含药血清组是在不同浓度的DDP基础上予以10％保元排毒丸含药血清进行培养。培养24h后分别以荧光显微镜、电镜、流式细胞仪检测细胞凋亡情况。结果：与空白血清组比较，荧光显微镜下模型组凋亡细胞增多，而模型＋含药血清组凋亡细胞数明显减少；电镜下模型组细胞受损明显，而模型＋含药血清组细胞形态基本正常。流式细胞仪检测细胞凋亡率，空白对照组为2．45％；各DDP组明显增加，10μg／mL组和6／μg／mL组分别为31．80％和30．98％，与空白对照组比较差异有统计学意义，P〈0．001；各含药血清组明显减少，DDP 10μg／mL＋含药血清组和DDP 6μg／mL＋含药血清组分别为15．21％和14．27％，与相应模型组比较差异有统计学意义，P〈0．001。模型组bcl-2基因及突变型p53基因的表达均明显降低，相应含药血清组的表达均有所上调。结论：保元排毒丸能减轻顺铂所致LLC—PK1细胞的凋亡，上调凋亡抑制基因bcl-2和突变型p53，可预防或降低顺铂引起的肾毒性。     

Elemental composition and water content of myelinated axons and glial cells in rat central nervous system

The distribution of elements (e.g. Na, Cl, K) and water in CNS cells is unknown. Therefore, electron probe X-ray microanalysis (EPMA) was used to measure water content and concentrations (mmol/kg dry or wet weight) of Na, Mg, P, S, Cl, K and Ca in morphological compartments of myelinated axons and glial cells from rat optic nerve and cervical spinal cord white matter. Axons in both CNS regions exhibited similar water content ( 90%), and relatively high concentrations (wet and dry weight) of K with low Na and Ca levels. The K content of axons was related to diameter, i.e. small axons in spinal cord and optic nerve had significantly less (25–50%) K than larger diameter axons from the same CNS region. The elemental composition of spinal cord mitochondria was similar to corresponding axoplasm, whereas the water content (75%) of these organelles was substantially lower than that of axoplasm. In glial cell cytoplasm of both CNS areas, P and K (wet and dry weight) were the most abundant elements and water content was approximately 75%. CNS myelin had predominantly high P levels and the lowest water content (33–55%) of any compartment measured. The results of this study demonstrate that each morphological compartment of CNS axons and glia exhibits a characteristic elemental composition and water content which might be related to the structure and function of that neuronal region.     

Regulators of Cardiac Cell Growth, Differentiation, and Apoptosis

The pathogenesis of heart hypertrophy and failure have been the focus of intense clinical and basic science investigation, yet the signal transduction pathways and molecular process that underlie the compensatory growth process that ultimately leads to heart failure remain enigmatic. Since ventricular myocytes have exited the cell cycle, growth of the myocardium in response to hemodynamic load occurs by cellular hypertrophy and not by hyperplasia. In this article, we document the potential involvement of tumor suppressor pocket proteins and cell cycle regulators that may impinge on the growth, differentiation, and apoptosis of cardiac muscle. This revised version was published online in August 2006 with corrections to the Cover Date.     

自体表皮细胞培养与异体真皮组合应用研究

严重烧伤病人皮肤修复中主要未解决的问题是真皮的替代。动物实验结果表明，异体皮移植后５天，用自体培养表皮细胞膜片覆盖真皮床，１４天后复合皮成活率是８４．６％±２．４％。组织学检查证实表皮已形成了复层结构，可见基底层、颗粒层和角质层。临床应用中，异体皮移植后１０天，去除异体表皮覆盖病人的自体培养表皮，３５天后未见排斥征象，异体真皮促进了培养表皮的分层、成熟和完整，组织学检查证实表皮细胞的边缘清楚，已分化形成颗粒层和角质层，真皮多细胞，已血管化，但表皮嵴缺乏。     

产科诊断剂量超声波对培养细胞影响的实验研究

采用模拟在人体中使用的实测超声剂量，对体外培养的Ｌ－９２９株细胞进行辐照，通过细胞回复能力试验，观察回复前后的细胞增殖与抑制。对体外培养的人胚肺纤维细胞经１次及５次辐照，观察了ＤＮＡ及细胞核面积的影响。并通过电镜观察了细胞超微结构的变化。上述实验结果，均提示经辐照后细胞有增殖趋向