肌肉组织工程的基础研究-不同培养条件对卫星细胞增殖的影响

研究不同培养条件对卫星细胞体外增殖的影响,寻找理想的培养条件。方法：通过MTT法绘制生长曲线,比较不同胎牛血清、不同血清浓度、不同培养液配方对卫星细胞增殖的影响。通过贴壁试验比较胶原和多聚赖氨酸对卫星细胞贴壁的影响。结果：不同的血清、不同的浓度以及不同的培养液配方对卫星细胞增殖影响明显。含有10％四季青胎牛血清的DMEM／F12(2:1)的培养液可以获得最高的增殖效率。胶原更有利于细胞的贴壁。结论：以本试验得出的培养条件可以使卫星细胞培养周期缩短1倍以上,为肌肉组织工程的研究创造了良好的条件。．     

人退变椎间盘髓核细胞体外平面培养的形态学及活性观察

[目的]观察平面培养体系内人退变椎间盘髓核细胞的形态及活性变化.[方法]收集20例人退变椎间盘髓核,分离髓核细胞行平面培养,倒置相差显微镜和HE染色观察髓核细胞的生长过程与形态变化,流式细胞仪量化细胞周期分布和凋亡率,甲苯胺蓝染色和免疫细胞化学染色髓核细胞聚集蛋白聚糖和Ⅱ型胶原的表达,观察平面培养传代对髓核细胞活性和基质合成能力的影响.[结果]原代髓核细胞呈类圆形或多角形,平均7d贴壁,31 d融合至95％,P1代髓核细胞呈长梭形或多角形,平均12h贴壁,6.6d融合至95％,两代细胞增殖能力的差异有统计学意义(P＜0.01).原代与P1代髓核细胞的细胞浆阳性染色聚集蛋白聚糖和Ⅱ型胶原,生长融合至95％后约90％的细胞分布于G1期,约16％的细胞凋亡,两代细胞的细胞活性和基质合成能力无统计学差异(P＞0.05).[结论]人退变椎间盘髓核细胞体外平面培养将经历显著的形态学变化.传一代后髓核细胞增殖能力提高,但能维持细胞活性以及蛋白聚糖和Ⅱ型胶原的合成能力.     

成人退变髓核细胞体外培养和细胞周期测定

[目的] 建立成人退变髓核细胞的单层培养模型并观察其形态;测定其细胞周期,探讨传代后髓核细胞生长不佳的原因.[方法] 取24例椎间盘突出症患者手术切除的椎问盘组织,分离出髓核组织,胰酶和胶原酶消化,DMEM/12培养基培养.倒置相差显微镜观察其形态学特征,流式细胞分析仪检测原代和P2细胞周期.[结果] (1)原代髓核细胞生长良好,7 d后贴壁生长的细胞可达90%.(2)原代细胞凋亡率为(38.10±11.7)%,P2代凋亡率为(44.74±17.6)%,原代S期细胞(7.88±2.1)%,P2 S期细胞(2.76±0.7)%.[结论] 传代后的髓核细胞凋亡率增高,S期细胞减少明显.     

兔髓核内细胞的培养及生长曲线的测定

目的 建立兔髓核内细胞的体外培养方法，绘制其生长曲线。方法取一月龄新西兰兔的髓核，胰酶和胶原酶消化，DMEM／F12培养基中培养，倒置显微镜观察细胞形态。MTT法测定细胞OD值以绘制其生长曲线。结果 原代培养髓核内细胞多为多角形，另有细胞为圆形或椭圆形，内含空泡。随传代培养的次数增加，细胞形态渐变为梭形，出现反分化的特性。生长曲线显示，髓核内细胞在19d时达到高峰。结论 功建立了兔髓核细胞体外培养体系，为组织工程化椎间盘的研究打下基础。在实际应用时，以采取次代细胞为佳，并应将其培养至第19天。     

成人退变性椎间盘髓核细胞体外培养及形态学观察

目的通过对成人退变椎间盘髓核细胞的体外培养和形态学观察,进一步研究细胞因素在椎间盘退变中的作用机制。方法取5例患椎间盘突出症并行椎间盘摘除手术的成人髓核,分离后在培养基中进行髓核细胞培养,细胞染色、逆转录聚合酶链式反应、免疫荧光检测细胞Ⅰ、Ⅱ型胶原的表达。结果椎间盘髓核细胞可在体外培养,30d后方可进行传代,最佳的培养条件为胎牛血清/培养基体积分数为10%～20%,pH值7.0。髓核细胞中出现Ⅰ型胶原,并具有较高的表达,Ⅱ型胶原表达微弱。结论成人退变髓核细胞体外培养时间较长,细胞增殖能力低下,特定培养条件的摸索是成功与否的关键。     

大鼠椎间盘软骨终板细胞凋亡体外模型的建立

[目的]建立大鼠椎间盘软骨终板细胞凋亡体外模型.[方法]为了模拟椎间盘内部低营养低代谢环境,采用低胎牛血清培养法培养椎间盘软骨终板细胞分别含0％,1％,3％,5％,8％,10％胎牛血清,设置不同浓度梯度筛选最佳浓度,检测凋亡率、凋亡蛋白表达及caspase酶活性.[结果]低胎牛血清培养组细胞发生形态改变,DAPI染色阳性细胞增多;流式细胞仪检测凋亡率随着FBS浓度降低而升高,1％为最有效诱导凋亡浓度;Western blot示FAS、caspase-3、PARP、细胞色素C表达在1％ FBS组明显高于10％时,同时caspase-3/8/9酶活性增高.[结论]低胎牛血清培养法能诱导体外培养的软骨终板细胞发生凋亡,最终会引起细胞功能丧失和椎间盘退变,caspase家族可能参与了这一过程.     

微载体旋转立体培养成人退变髓核细胞增殖及生长动力学研究

[目的]通过单层培养和微载体旋转立体培养成人退变髓核细胞对比,研究两种培养方式对其生长活性及增殖能力的影响.[方法]本实验通过Trypan blue法计数细胞并绘制生长曲线,应用3H- TdR放射免疫法检测退变髓核细胞增殖活性,流式细胞仪检测退变髓核细胞周期,比较两种培养方式对细胞增殖的影响.[结果]微载体旋转立体旋转培养较单层培养细胞从贴壁到对数生长期开始时间( 16～20 d)较长,但是严格意义的稳定生长期(3～5 d)很短;对数生长期长,一般14 ～ 17 d,期间细胞增殖活跃.两种培养方式的细胞处于稳定生长期时,细胞增殖能力没有明显区别,而处于对数生长期时,微载体培养的细胞的增殖能力明显高于单层培养组的细胞(P＜0.05).细胞周期测定显示两种细胞停滞在G0/G1期的占71％左右,培养方式对其影响不明显.而微载体培养的细胞的S期明显较单层培养的细胞为长(P＜0.05).[结论]成人退变髓核应用微载体培养后增殖能力及生长活性提高,可解决组织工程学椎间盘种子细胞难以收集的难题,为将来开展椎间盘组织工程学的研究奠定良好的基础.     

兔不同节段椎间盘髓核细胞培养特性的比较

目的:探讨兔颈段、胸段及腰段椎间盘髓核细胞的培养特性.方法:3～4月龄兔10只,麻醉后,在无菌条件下手术分离整段脊柱,分别取颈段(C1/2～C7/T1)、胸段(T1/2～T1/L1)、腰段(L1/2～L7/S1)髓核细胞进行培养,于培养后的24h计算贴壁率.并于贴壁后的第3、7、14及21天计算细胞死亡/成活比,判断细胞活力并检测蛋白多糖的含量.结果:颈段、胸段、腰段细胞贴壁率差异具有显著性,腰段细胞贴壁牢最高(P<.01).不同节段之间,在多个时间点观察髓核细胞死亡/存活比差异具有显著性,腰段椎间盘髓核细胞的死亡/成活比最低(P<0.01).不同节段之间,不同时间点观察的蛋白多糖含量差异具有显著性,且腰段椎间盘髓核细胞的蛋白多糖含量最高(P<.01).结论:腰段椎间盘髓核细胞较颈段及胸段的髓核细胞生长状态好,兔腰椎髓核细胞更适宜作为细胞培养的种子细胞.     

pH值对人退变椎间盘髓核细胞凋亡的影响

[目的]观察不同pH值对体外培养人退变椎间盘髓核细胞凋亡的影响,为椎间盘退变的预防与治疗提供理论依据。[方法]对体外培养的人退变椎间盘髓核细胞利用甲苯胺蓝和番红O染色进行鉴定,并对P3代细胞分别用普通培养基(pH值7.4)、酸性培养基(pH值6.8)和酸性培养基(pH值6.8)+Cucl_2(酸质子受体抑制剂)培养24 h,用流式细胞仪测定细胞凋亡,计算细胞凋亡率。[结果]细胞染色结果均为阳性,证明实验中所培养的细胞为髓核类软骨细胞。普通培养基组的凋亡率为(8.86±0.20)%,酸性培养基组的凋亡率为(11.23±0.77)%,酸性培养基+Cucl_2组的凋亡率为(9.60±0.49)%。与其他两组相比,酸性培养基组的凋亡率明显增加(P0.05)。[结论]在低pH值的环境下,人退变椎间盘髓核细胞的凋亡率增加。     

羧甲基壳聚糖对体外培养髓核细胞增殖及硝普钠诱导凋亡的影响

[目的]研究不同浓度羧甲基壳聚糖对体外培养椎间盘髓核细胞增殖及硝普钠诱导细胞凋亡的保护作用.[方法]体外培养大鼠椎间盘髓核细胞,Ⅱ型胶原免疫组化染色鉴定;分别加入不同浓度羧甲基壳聚糖培养24h,通过CCK-8细胞计数法检测髓核细胞的增殖情况;采用不同浓度硝普钠诱导髓核细胞凋亡,通过流式细胞仪检测早期凋亡细胞比例,并通过Hoechst 33342荧光染色检测髓核细胞凋亡核的形态学变化.[结果]CCK-8检测结果表明10～500μg/ml羧甲基壳聚糖作用髓核细胞24 h对髓核细胞增殖无明显作用(P＞0.05);流式细胞检测结果表明1～3mmol/L的硝普钠可诱导髓核细胞发生早期凋亡,加入50～200μg/ml羧甲基壳聚糖后硝普钠诱导的髓核细胞凋亡有不同程度的降低(P＜0.05).Hoechst 33342染色结果表明羧甲基壳聚糖可降低硝普钠诱导髓核细胞凋亡.[结论]一定浓度的羧甲基壳聚糖对髓核细胞增殖无明显影响,羧甲基壳聚糖对硝普钠诱导下髓核细胞凋亡有保护作用.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

The multiply injured child

Blunt trauma is the principal cause of childhood death in many developed countries. This review outlines the differences between adults and children with respect to resuscitation and treatment of orthopaedic injuries in a child with polytrauma. Recent advances in techniques of fracture stabilization are reported.     

Development of Selective Low-Density Lipoprotein (LDL) Apheresis System: Immobilized Polyanion as LDL-Specific Adsorption for LDL Apheresis System

Abstract: Low-density lipoprotein (LDL) is widely recognized as one of the major risk factors for developing coronary heart diseases. Despite intensive development of LDL-lowering drugs, there still exist those patients with refractory hyperlipidemia whose plasma LDL levels are not sufficiently lowered by drugs. LDL apheresis, direct removal of plasma LDL from circulating blood, is thought to be the most promising treatment for such refractory patients. Various techniques, such as the use of an im-munoadsorbent utilizing an anti-LDL antibody, have been used in an attempt to achieve the selective removal of LDL. However, none were widely used because of complications, poor selectivity, and so forth. To establish a safe and effective LDL apheresis system, we chose a synthetic affinity adsorbent as the LDL-removing device. Synthetic polyanion compounds were used as the affinity ligands for LDL adsorbent to simulate the anion-rich sequence of LDL binding sites in the human LDL receptor. Among various polyanion compounds, those polyanions with sulfate or sulfonate groups and hydrophilic backbone were found to have strong affinity for LDL. In contrast, polyanions with carboxyl groups showed poor affinity. Dextran sulfate (DS) was selected as the affinity ligand of LDL adsorbent for its high affinity and low toxicity. The influence of its charge density and molecular weight on its affinity for LDL was suitable. The affinity rapidly increased as the charge density increased, then, reached a constant value. Little affinity was found for either the DS monomer (glucose sulfate) or DS with a molecular weight higher than 10⁴ daltons whereas DS with molecular weights in the midrange showed strong affinity. DS with a midrange molecular weight was immobilized on cellulose hard gel to give LDL adsorbent clinical application. The adsorbent demonstrated an excellent selectivity for LDL and very low density lipoprotein (VLDL) in vitro. Adsorption of high-density lipoprotein and major plasma proteins was almost negligible. Additional study of the LDL-binding mechanism revealed that DS directly interacts with positively charged sites on LDL, which demonstrates that the nature of the interaction is the same as that of LDL receptor. An LDL adsorption column (Liposorber) packed with an LDL adsorbent and polysulfone hollow-fiber plasma separator (Sulflux) was developed as an efficient LDL apheresis system. Clinical investigation proved that this system is capable of intensively lowering the plasma LDL level without affecting major plasma components.     

Artificial organs 2010: a year in review

In this Editor's Review, articles published in 2010 are organized by category and briefly summarized. As the official journal of The International Federation for Artificial Organs, The International Faculty for Artificial Organs, and the International Society for Rotary Blood Pumps, Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level."Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide such meaningful suggestions to the author's work whether eventually accepted or rejected and especially to those whose native tongue is not English. Without these excellent and dedicated reviewers the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, Wiley-Blackwell, for their expert attention and support in the production and marketing of Artificial Organs. In this Editor's Review, that historically has been widely received by our readership, we aim to provide a brief reflection of the currently available worldwide knowledge that is intended to advance and better human life while providing insight for continued application of technologies and methods of organ Replacement, Recovery, and Regeneration. We look forward to recording further advances in the coming years.     

Avaliação do clube de revista de anestesiologia por meio de mudanças semânticas

Background and objectives

The interactive approach of a journal club has been described in the medical education literature. The aim of this investigation is to present an assessment of journal club as a tool to address the question whether residents read more and critically.

Methods

This study reports the performance of medical residents in anesthesiology from the Clinics Hospital – University of São Paulo Medical School. All medical residents were invited to answer five questions derived from discussed papers. The answer sheet consisted of an affirmative statement with a Likert type scale (totally disagree–disagree–not sure–agree–totally agree), each related to one of the chosen articles. The results were evaluated by means of item analysis – difficulty index and discrimination power.

Results

Residents filled one hundred and seventy three evaluations in the months of December 2011 (n = 51), July 2012 (n = 66) and December 2012 (n = 56). The first exam presented all items with straight statement, second and third exams presented mixed items. Separating “totally agree” from “agree” increased the difficulty indices, but did not improve the discrimination power.

Conclusions

The use of a journal club assessment with straight and inverted statements and by means of five points scale for agreement has been shown to increase its item difficulty and discrimination power. This may reflect involvement either with the reading or the discussion during the journal meeting.     

Lymphocytapheresis

Abstract: Leukocytapheresis has long been performed with the centrifugal method. But in 1989 in Japan, the Asahi Medical Co. developed the extracorporeal leukocyte-removal filter, Cellsorba. This filter consists of non-woven fabric, which can remove leukocytes from whole blood during extracorporeal circulation. In the incipient stage, this filter was applied to collagen diseases, rheumatoid arthritis, and systemic lupus erythematosus. During the following studies, this filter has been found to have an immunosuppressive effect. Now, it is beginning to be applied to various kinds of autoimmune diseases. Moreover, this filter has recently been recognized to be effective in inflammatory bowel diseases, ulcerative colitis, and Crohn's disease. The outline of Cellsorba and the application of this filter is described here.     

Soluble TNFα Receptors Are Increased in Chronic Renal Insufficiency and Hemodialysis and Inhibit Neutrophil Priming by TNFα

Abstract: The oxidative burst of neutrophils from azotemic patients is refractory to priming by tumor necrosis factor-α (TNFα). Soluble TNFα binding proteins (TNFR) accumulate in the plasma of azotemic patients. To test the hypothesis that these increased sTNFR concentrations inhibit TNFa priming of oxidative burst activity, we measured plasma sTNFR concentrations in nondialyzed azotemic patients, hemodialysis patients, and normal subjects, and determined TNFa priming of fMet-Leu-Phe-stimulated superoxide production in neutrophils incubated in plasma with differing levels of sTNFR. These sTNFR concentrations increased significantly as creatinine clearance decreased and were significantly greater in hemodialysis patients than could be accounted for by loss of renal function alone. TNFα primed superoxide production by normal neutrophils in normal plasma, but this effect was significantly reduced in plasma with increased concentrations of sTNFR. Neutrophils from azotemic and hemodialysis patients were refractory to priming by TNFα in autologous plasma, and incubation in normal plasma only partially corrected this defect. We conclude that sTNFR accumulate as a result of the loss of renal function and hemodialysis and inhibit TNFα priming of neutrophils in azotemic and hemodialysis patients, but that these cells also have an intrinsic functional defect.