大鼠羊膜上皮细胞体外培养的初步研究

目的： 研究大鼠羊膜上皮细胞（AECs）在体外培养时的形态变化和其生长特性，探讨EGF和血清对AECs生长和增殖性的影响。 方法: 分别取妊娠中期SD大鼠（12-14 d）和妊娠晚期SD大鼠（18-19 d）的羊膜，制成AECs单细胞悬液，用DMEM/F12培养液培养、传代。光镜、扫描电镜下观察其生长的形态变化； MTT法检测EGF和血清对AECs生长和增殖性的影响。 结果： 妊娠中期和晚期AECs在体外培养时均生长良好、增殖活跃，但妊娠晚期AECs生长周期相对较短。 结论： EGF和血清均能促进AECs增殖，其中EGF促进AECs的增殖更为显著。这为利用AECs进行细胞治疗和组织工程技术奠定了实验基础。     

低频电磁场对胶原海绵支架培养的表皮干细胞增殖的影响

目的:探讨低频电磁场(LFEMF)对Ⅰ型胶原海绵支架培养的人表皮干细胞(hEsCs)增殖的影响及其在皮肤组织工程中的作用.方法:将体外分离纯化的hESCs种植于胶原海绵生物支架材料.经LFEMF治疗仪(场强5 mT,频率分别为1、10和50 Hz)刺激hESCs(30 min/d),通过肉眼、镜下观察,HE染色,DAPI荧光核染色及扫描电镜观察hESCs生长情况,并收集培养2、7、10和14 d hESCs的DAPI核荧光染色数据,用显微图像软件分析细胞增殖数目,比较各时间点细胞增殖的统计学差异.结果:hESCs在胶原海绵支架生长良好;各频率组LFEMF刺激均能促进hESCs增殖,频率不同.促增殖的效应不一(P＜0.05).结论:胶原海绵可作为体外培养hESCs的良好支架,在LFEMF干预下可实现hESCs较快速扩增,LFEMF在皮肤组织工程中具有较大应用潜力.     

用聚乳酸海绵材料构建组织工程真皮

目的 利用多孔聚乳酸海绵材料作为真皮支架材料，研究其在组织工程真皮构建中的作用及意义。方法 采用盐溶法制作出多孔聚乳酸海绵材料，再接种皮肤成纤维细胞，形成细胞—支架结构物；利用细胞计数、组织染色、电镜和免疫组化等检测手段，观察细胞在材料上的生长、增殖及分泌情况。结果 成纤维细胞在支架材料上状态良好，且能缓慢增殖。胞外基质丰富，胶原分泌旺盛。结论 聚乳酸能支持皮肤成纤维细胞正常的生理代谢和分泌，是理想的组织工程真皮支架材料。     

胶原海绵支架体外构建组织工程膀胱黏膜***◆

背景：组织工程膀胱黏膜层的构建在组织工程膀胱修复中占有重要的地位,但目前并没有最合理的构建方法。 目的：探讨胶原海绵支架复合猪膀胱尿路上皮细胞体外构建膀胱黏膜结构的可行性。 方法：刮取猪膀胱黏膜层后用酶消化方式进行猪膀胱尿路上皮细胞原代培养,并进行尿路上皮细胞标志物免疫荧光和RT-PCR鉴定。制备疏松多孔的胶原海绵支架材料,将第3代尿路上皮细胞接种在胶原海绵支架上,体外培养4~8 d后观察尿路上皮细胞和胶原海绵材料的复合情况。 结果与结论：原代培养的猪膀胱尿路上皮细胞呈“多角形”、“铺路石”样,以克隆团形式生长。免疫荧光鉴定AE1/AE3阳性,RT-RCR检测uroplakin-ⅠA、uroplakin-Ⅱ阳性。胶原海绵复合尿路上皮细胞体外培养4~8 d后,细胞在胶原海绵支架上生长良好,覆盖胶原材料的表面并长入材料内部,保持了尿路上皮细胞的特性。体外培养6 d时,尿路上皮细胞与胶原支架复合效果最好,同时细胞数量也最多。结果初步表明了胶原海绵复合膀胱尿路上皮细胞可以构建组织工程膀胱黏膜,且体外培养6 d为最佳时间点。     

羊膜上皮细胞胶原海绵复合体促大鼠预构皮瓣成活及其再血管化

目的　移植羊膜上皮细胞(AECs) 胶原海绵复合体促进预构皮瓣成活。 方法　第3代SD大鼠AECs、软骨细胞株分别植于胶原蛋白海绵支架,并提取AECs组上清液行促血管形成因子VEGF、TGFβ1、bFGF的ELISA检测。SD大鼠分正常对照组、空白对照组、软骨细胞组和AECs组。一期手术后第7、14 d取皮瓣组织行促血管形成因子的ELISA检测。二期手术后第7 d用计算机图像分析系统测定皮瓣存活率,取存活部位组织行HE染色、vWF免疫组织化学染色以分析微血管密度。 结果　AECs复合体上清液中的促血管形成因子分泌逐渐增多;组织内各因子含量以AECs组最高,AECs组皮瓣存活率明显高于空白对照组和软骨细胞组。AECs组皮肤微血管面积比、vWF因子阳性区面积比明显高于其他组。 结论　植入AECs胶原海绵复合体可促进预构皮瓣的存活,与其分泌的一些促血管形成因子促进预构皮瓣再血管化有关。     

胶原复合梯度磷酸三钙负载软骨细胞的体外培养

目的 观察新型三维支架材料胶原复合梯度磷酸三钙在体外与软骨细胞的相容性和黏附性,评价其作为软骨组织工程支架的可行性.方法 取8周龄新两兰大白兔膝关节软骨,以酶消化法获得高纯度软骨细胞,培养3代后与三维支架材料胶原复合梯度磷酸三钙在体外复合培养.用倒置相差显微镜、HE染色、免疫组织化学及扫描电镜观察软骨细胞形态、Ⅱ型胶原表达及成软骨能力,同时观察支架材料与软骨细胞的相容性.结果 扫描电镜观察显示支架材料具有疏松多孔结构,孔隙结构规则,孔径100～150 μm,材料内部孔与孔之间贯通良好.支架亲水性好.软骨细胞吸附于支架表面,增殖并逐渐顺孔隙迁徙至支架内部,在孔壁贴附良好,表型维持稳定,可分泌细胞外基质.结论 胶原复合梯度磷酸三钙三维支架具有良好的细胞相容性.     

生长分化因子5诱导脂肪干细胞复合Ⅰ型胶原支架成软骨细胞的分化

背景：前期实验中发现生长分化因子5可以诱导脂肪干细胞向软骨细胞分化,但在复合Ⅰ型胶原支架的体外培养条件下其向软骨细胞分化的能力尚未见研究报道。 目的：探讨生长分化因子5诱导脂肪干细胞复合Ⅰ型胶原支架向软骨细胞分化的能力。 方法：从兔脂肪组织中分离培养脂肪干细胞,使用倒置相差显微镜观察细胞形态,使用免疫荧光对其表型进行鉴定。在复合Ⅰ型胶原支架条件下,加入外源性生长分化因子5对脂肪干细胞向软骨细胞进行诱导,在诱导14 d时,采用苏木精-伊红染色和扫描电镜对诱导的细胞进行形态学观察。在诱导7,14和21 d时,采用反转录PCR方法检测诱导的细胞的Ⅱ型胶原和蛋白多糖mRNA表达情况。 结果与结论：原代脂肪干细胞贴壁生长,呈梭形、多角形分布,细胞表面抗原CD44、CD49d 阳性,CD106 阴性。生长分化因子5诱导的脂肪干细胞与Ⅰ型胶原支架黏附良好,增殖能力旺盛,细胞表面存在着大量的细胞外基质分泌,Ⅱ型胶原和蛋白聚糖mRNA表达水平明显增加。说明生长分化因子5能够成功诱导复合Ⅰ型胶原支架的脂肪干细胞成软骨细胞分化。     

血管组织工程支架材料的细胞相容性

背景：胶原与透明质酸均有利于组织培养中细胞的黏附、增殖和分化。 目的：观察血管内皮细胞、平滑肌细胞与胶原/透明质酸膜、明胶海绵的细胞相容性,并筛选最佳种植方法。 方法：将第3-5代兔血管平滑肌细胞种植在胶原/透明质酸膜(或明胶海绵)材料上,连续培养2周后将兔内皮细胞接种在平滑肌细胞-胶原/透明质酸膜(或明胶海绵)复合体上,并设置单纯平滑肌细胞与内皮细胞共同接种组。 结果与结论：①光镜和扫描电镜观察：细胞在两种材料上均随着培养时间,接种次数增加而生长加快,其中在胶原/透明质酸膜上的细胞生长更好,细胞连接更致密。②WST-1法检测：胶原/透明质酸膜组平滑肌细胞的黏附率及增殖率均高于明胶海绵组(P < 0.05),且细胞在材料上的生长随着接种次数的增加有不同程度提高。③³H-TDR掺入法检测DNA合成率：在胶原/透明质酸膜上的细胞DNA合成最高,明胶海绵上的较差。表明胶原/透明质酸膜具有较理想的细胞相容性,采用适当间隔、反复接种的方法可提高细胞的黏附和增殖。     

多孔碳酸钙陶瓷与干细胞源性成骨细胞的相容性

背景：国内外的研究证实普通碳酸钙陶瓷作为骨替代材料时具有细胞支架作用。 目的：观察多孔碳酸钙陶瓷与成骨细胞的相容性,及作为骨组织工程支架的可能性。 方法：SD大鼠骨髓基质干细胞经矿化诱导培养、扩增并检测证实其已具成骨细胞表型后,分别与多孔碳酸钙陶瓷支架、普通羟基磷灰石陶瓷支架体外复合培养。 结果与结论：骨髓基质干细胞经体外诱导形成成骨细胞,钙结节、Ⅰ型胶原和碱性磷酸酶免疫染色结果阳性。多孔碳酸钙陶瓷支架材料与羟基磷灰石陶瓷材料皆有细胞附着生长,但多孔碳酸钙陶瓷支架材料细胞的黏附能力、增殖活力及成骨活性均强于羟基磷灰石陶瓷材料。提示多孔碳酸钙陶瓷支架材料与SD大鼠骨髓基质干细胞源性成骨细胞有良好相容性。     

胶原改良聚乳酸电纺丝支架用于组织工程化输尿管的体外构建***

背景：聚乳酸是一种应用广泛的细胞支架材料,但其疏水性和缺乏细胞识别信号影响了在组织工程器官构建中的应用。 目的：探讨Ⅰ型胶原蛋白改良聚乳酸电纺丝支架体外构建组织工程化输尿管的可行性。 方法：用Ⅰ型胶原蛋白醋酸溶液冻干法处理聚乳酸电纺丝,使Ⅰ型胶原蛋白吸附于电纺丝纤维表面,制成胶原改良电纺丝支架。将分离培养的输尿管上皮细胞分别接种于改良聚乳酸电纺丝支架和未处理的聚乳酸电纺丝支架上。 结果与结论：MTT检测显示输尿管上皮细胞在改良支架中生长良好,细胞整体活性在各时间点均明显优于未处理的聚乳酸电纺丝支架上的细胞。扫描电镜观察发现细胞在改良支架表面黏附良好,接种后5 d,支架表面大部分已被增殖的输尿管上皮细胞覆盖。说明胶原改良聚乳酸电纺丝支架能明显提高种子细胞的黏附和增殖活性,可用于体外构建组织工程化输尿管。 关键词：输尿管;电纺丝;聚乳酸;胶原;黏附;增殖;组织工程 doi:10.3969/j.issn.1673-8225.2012.12.002     

Modes of reinforcement and gender and culture of experimenter and subject: effects of "alien" and external reinforcement for Japanese and American men and women

In this study, we examined external and "alien" reinforcement (ER and AR. respectively) as a factor in social learning, and studied the combined effects of culture and reinforcement mode. A female (Experiment 1) and a male (Experiment 2) experimenters conducted experimental sessions. Both men and women, who grew up in the same culture as the experimenter, participated and performed the experimental task. A three-way interaction effect of experimenter gender, culture, and reinforcement mode was found on task performance. And the effect was more pronounced for a Japanese experimenter. A female and a male experimenters conducted Experiments 3 and 4, respectively; however participants this time were men and women who grew up in different cultures than the experimenter. Results indicated that the pattern of the subject gender and reinforcement mode interaction effect, when the experimenter was Japanese with American subjects, was exactly opposite to that when the experimenter was American. These experiments showed that AR was as effective for social learning as ER, and that the cultural backgrounds of experimenter and subject influenced AR and ER effectiveness.     

Rates of oxygen consumption and of anaerobic glycolysis in renal cortex and medulla of adult and new-born rats and guinea-pigs

1. Rates of oxygen uptake and of anaerobic glycolysis were estimated in slices from the renal cortex and medulla (a) of adult rats and guinea-pigs, (b) of new-born (1-, 5- and 21-day-old) rats and of guinea-pigs of 1, 12, 21, 24 and 120 hr age.2. In the adult rat, Q(O2) values for the cortex were 12.55 +/- 0.20 (22) and for the medulla: 8.56 +/- 0.17 (22) mul./hr.mg dry weight, while in the new-born rat (24 hr old) they were 10.99 +/- 0.46 (12) and 9.33 +/- 0.18 (9) mul./hr.mg dry weight respectively.3. Values for Q(CO2) (N2) (anaerobic glycolysis) in the 14 hr old new-born rat were in the renal cortex 9.65 +/- 0.35 (5) and in the medulla 7.39 +/- 0.43 (5) mul./hr.mg dry weight; while in the adult they were 2.25 +/- 0.08 (16) and 5.76 +/- 0.14 (16) mul./hr.mg dry weight, respectively.4. In the adult guinea-pig values for Q(CO2) (N2) were of the same order as in the adult rat, though the rate of O(2) uptake was for the cortex 8.12 +/- 0.22 (12) and for the medulla 5.02 +/- 0.23 (11) mul./hr.mg dry weight.5. Though the Q(O2) values in the renal cortex and medulla were smaller in the 1 hr old new-born guinea-pig, they were already increasing in the 12 hr old neonate.6. The results are discussed in the light of enzyme changes occurring during the process of maturation of the nephron as indicated by histochemical observations.     

Timing and intensity of early fevers and the development of allergies and asthma

BACKGROUND: Early childhood fevers appear to protect against later allergies and asthma. What is not known is the time in which fevers exert this effect and whether the degree of temperature increase is important. OBJECTIVE: We sought to examine the relationship between the time and degree of early fevers and later allergies and asthma. METHODS: Eight hundred thirty-five children from southeast Michigan were enrolled at birth. Clinic records from their first 2 years were abstracted for episodes of fever. At age 6 to 7 years, children underwent allergy testing. We examined fevers occurring within 6-month intervals in the first 2 years of life and outcomes at age 6 to 7 years. The primary outcome measures were allergic sensitization, asthma, asthma with allergic sensitization, and asthma without allergic sensitization. RESULTS: In the unadjusted analysis each episode of fever between 7 and 12 months of age was associated with a lower odds of allergic sensitization (odds ratio [OR], 0.71; 95% CI, 0.54-0.93) and asthma with allergic sensitization (OR, 0.43; 95% CI, 0.21-0.90) at age 6 to 7 years. Likewise, every 1 degrees C increase in the maximum temperature between 7 and 12 months was associated with a lower odds of allergic sensitization (OR, 0.77; 95% CI, 0.61-0.96) and asthma with allergic sensitization (OR, 0.62; 95% CI, 0.40-0.94). After adjusting for potential confounders, each episode of fever between 7 and 12 months was associated with a lower likelihood of asthma with allergic sensitization (adjusted OR, 0.33; 95% CI, 0.11-0.94) at age 6 to 7 years. CONCLUSIONS: Both the timing and intensity of childhood fevers appear to be important factors in the development of allergies and asthma.     

纳米水平分子成像与诊疗一体化研究进展与挑战

分子成像能以非侵入性的方式重现活体细胞的生理功能和生物学过程,提高疾病的早期和特异性诊断水平。纳米颗粒/材料具有物理性质可控性高、易于表面修饰、血液循环时间长和可功能化等优点,在疾病诊断与治疗中显示出巨大潜力。但如何阐明纳米材料多功能间的内在联系、解决其代谢及安全性等关键机制难题、实现纳米颗粒/材料多功能性到临床多功能...