青少年特发性脊柱侧凸患者骨髓间充质干细胞褪黑素信号通路初步研究

目的 研究青少年特发性脊柱侧凸(Ms)患者骨髓间充质干细胞(BMSCs)褪黑素信号通路是否存在异常.方法 24例12～18岁志愿者,AIS患者15例,正常对照组9例.分别从患者髂前上棘处穿刺抽取10 ml骨髓,肝素抗凝.采用密度梯度离心法分离BMSCs,体外培养并传至P3代,进行表型鉴定.取P3代BMSCs,先采用福斯可林刺激BMSCs内环磷酸腺苷(cAMP)升高,然后用不同浓度褪黑素刺激细胞,检测细胞内cAMP的水平.结果 分离的单个核细胞经培养至P3代,使用流式细胞仪进行细胞表型鉴定,体外培养细胞的表型与BMSCs的表面标志相符.AIS组和正常对照组BMSCs的cAMP的基础水平都很低,在给予福斯可林刺激以后,cAMP的水平明显升高,此后再给予生理剂量的褪黑素刺激后,两组cAMP水平的抑制程度差异无统计学意义(P>0.05);给予药理剂量的褪黑素刺激后,两组cAMP水平的抑制程度差异同样无统计学意义(P>0.05).结论 MS患者BMSCs褪黑素信号通路可能不存在异常.     

青少年特发性脊柱侧凸患者成骨细胞中核因子κB受体活化子配体和骨保护蛋白的表达

目的:从成骨细胞(osteoblast,OB)水平探讨核因子KB受体活化子配体(receptor activator of NFκBligand,RANKL)、骨保护蛋白(osteopmtegerin,OPG)与青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者骨量降低的关系.方法:AIS患者(AIS组)20例,男5例,女15例,年龄11～19岁,平均14.75岁,Cobb角40°～96°,平均59.65°;同年龄非脊柱畸形患者(对照组)8例,男6例,女2例,年龄10～19岁,平均15.25岁.两组均采用双能X线吸收测量仪(dual-energy X-ray absorptiometry,DEXA)测量骨密度(bone mineral density,BMD),测量部位包括非优势侧股骨近端及腰椎.所有受试者术中取适量髂前上嵴的松质骨,运用植块法培养成骨细胞.培养过程中观察细胞形态学变化,并用碱性磷酸酶染色法、钙结节染色法和RT-PCR检测骨钙素表达,并进行表型鉴定.取P2代细胞应用RT-PCR和Western blotting检测RANKL和OPG的mRNA及蛋白表达情况.结果:植块法培养可以获得较多的原代细胞.碱性磷酸酶染色、钙结节染色及RT-PCR检测骨钙素表达证实所培养的细胞表现成骨细胞特性.AIS组腰椎(L2～L4)及股骨近端的BMD值明显低于对照组;RANKL的核酸及蛋白水平的表达量均较对照组高(P<0.01):OPG的核酸及蛋白水平的表达量与对照组比较无统计学差异(P>0.05);RANKL/OPG比值明显高于对照组(P<0.01).结论:成骨细胞中RANKL及OPG在核酸及蛋白水平的表达异常可能与AIS患者骨量降低的分子机制相关.     

植块法在成骨细胞培养中的应用

目的：探讨植块法培养成骨细胞的可行性。方法：取10例先天性脊柱侧凸患者髂骨松质骨，应用植块法分离培养成骨细胞。培养过程中观察细胞形态学变化，并用碱性磷酸酶染色、RT-PCR检测Ⅰ型胶原和骨钙素表达、骨钙素免疫荧光检测、钙结节观察等方法对培养细胞进行鉴定。结果：应用植块法培养获得了较多的原代细胞，光镜下呈典型的成骨细胞形态，碱性磷酸酶染色、Ⅰ型胶原和骨钙素表达及钙结节形成等观察结果均证实所培养细胞表现成骨细胞特性。结论：植块法成骨细胞培养体系方法简单，在获得大量原代成骨细胞的同时，较好地保持了其生物学特征，是一种较理想的人成骨细胞培养方法。     

骨细胞分离培养及其与成骨细胞鉴别比较的实验研究

目的:建立比较稳定的骨细胞实验室分离培养方法,并将其部分生物学特性与实验室培养的成骨细胞进行比较研究,明确两者区别.方法:采用序列酶消化法,分别从3只3dSD乳鼠骨骼中分离培养骨细胞和成骨细胞,培养24 h后进行细胞形态学观察.第1代细胞用碱性磷酸酶试剂盒采用重氮盐法(改良Kaplow氏法)染色,采用免疫细胞化学法对细胞的骨钙素(BGP)染色,测定碱性磷酸酶并计算其活性.结果:骨细胞多呈星状或树枝状,且有很多的突触;成骨细胞呈长梭形,有少量的突触.骨细胞碱性磷酸酶染色,胞浆内cAKP颗粒不明显;成骨细胞碱性磷酸酶染色,胞浆内可见众多cAKP颗粒.骨细胞BGP染色阳性明显,成骨细胞BGP染色阳性不如骨细胞明显.ALP在骨细胞中分泌较成骨细胞低,且有统计学差异.结论:实验室条件下能培养出骨细胞,该类细胞和成骨细胞有明显区别.     

机械牵张应力对骨化颈椎后纵韧带成纤维细胞的影响

目的探讨机械牵张应力对体外培养的颈椎后纵韧带骨化症（OPLL）患者颈椎韧带成纤维细胞的影响。方法对2012年1月至2013年12月 OPLL 与颈椎外伤但无后纵韧带骨化（非OPLL）患者（各15例）行前路颈椎手术治疗,术中取韧带标本。采用组织块培养法进行细胞体外培养,免疫细胞化学及免疫荧光技术检测胞质波形蛋白。采用 Flexercell 4000细胞加载培养系统分别对两组患者第3代细胞进行机械牵张应力加载,逆转录-聚合酶链式反应（RT-PCR）方法检测两组成纤维细胞应力刺激前及刺激后12、24 h 成骨特异性指标骨钙素、碱性磷酸酶与Ⅰ型胶原 mRNA 表达。结果免疫细胞化学及免疫荧光检测显示胞质波形蛋白呈阳性表达。OPLL组后纵韧带成纤维细胞经机械牵张应力刺激12 h后,骨钙素、碱性磷酸酶及Ⅰ型胶原 mRNA 表达明显升高,应力刺激前后差异具有统计学意义;而非OPLL组应力刺激前后骨钙素、碱性磷酸酶及Ⅰ型胶原 mRNA 表达无明显变化。结论机械牵张应力可促使OPLL患者后纵韧带成纤维细胞骨钙素、碱性磷酸酶及Ⅰ型胶原mRNA表达增加,促进其骨化,其在OPLL进展中发挥重要作用。     

适宜电刺激对成骨细胞平面培养下细胞增殖分化及BMP-2表达的实验研究

目的:观察适宜电流刺激成骨细胞在平面培养下成骨细胞增殖及分化,明确是否具有促进增殖、分化作用,并观察电流刺激下BMP-2表达的变化。方法:将来自家兔幼仔颅骨提取的成骨细胞进行平面培养,2代之后进行分类培养,实验组进行电流刺激,并给予相同的刺激时间和刺激强度,对照组未进行电流刺激。之后在不同时间点进行细胞增殖、分化检测及BMP-2蛋白表达分析。结果:实验组8d内光镜下可见大量成骨细胞增殖,成骨细胞呈多形性改变,6～8d细胞内出现少量钙化点,而对照组骨细胞增殖缓慢。实验组分化明显,碱性磷酸酶及钙结节染色阳性,碱性磷酸酶定量分析显示逐渐增加。实验组经免疫组化分析显示BMP-2量逐渐增加。结论:电刺激可促进成骨细胞的增殖分化而达到实现细胞数目的短时间增加,细胞内部经过免疫组化染色后显示BMP-2表达增加。     

转化生长因子β对大鼠成骨细胞雌激素受体表达的影响

目的探讨转化生长因子β对大鼠成骨细胞雌激素受体表达的影响。方法实验中取雌性SD大鼠4肢松质骨,应用胶原酶消化法得到大量纯净成骨细胞;进行形态学观察,检测不同培养时间的细胞培养液的上清液中成骨细胞特征性分泌物:碱性磷酸酶(AKP)和骨钙素(OCN)的含量;碱性磷酸酶(ALP)染色(改良Gomori氏钙钴法);通过免疫组化法(SP法)进行雌激素受体染色;用不同浓度的TGFβ作用于体外培养的成骨细胞,进行SDSPAGE电泳和Westernblot检测雌激素受体。结果成骨细胞上清液AKP和OCN的分泌量明显高于成纤维细胞(P<0.01),形态学观察符合成骨细胞的特征。经免疫组化染色大鼠的成骨细胞存在雌激素受体,且位于胞核内。Westernblot结果显示,雌激素受体在TGFβ浓度为0.1～0.5ngml时,有较强的荧光发光信号条带。结论TGFβ在浓度为0.1～0.5ngml时,能提高成骨细胞雌激素受体基因表达水平,这可为研究TGFβ对于成骨细胞雌激素受体的作用机制及骨代谢疾病药物筛选提供新的支持。     

人小涎腺成纤维样单克隆细胞的成骨分化

目的：探索人小涎腺成纤维样单克隆细胞的体外培养、扩增方法,鉴定其性质,研究向成骨细胞分化的潜能。方法：组织块贴壁法原代培养人小涎腺细胞,收集成纤维样细胞,用96孔板稀释铺板法克隆培养,免疫荧光和RT-PCR检测细胞表型,并进行成骨诱导分化,通过骨钙素、一型胶原免疫细胞化学染色及碱性磷酸酶、茜素红钙结节染色鉴定成骨分化。结果：成功的在体外扩增培养出人小涎腺成纤维样单克隆细胞,免疫荧光证实细胞表达CD13、CD29、CD106和CD44,RT-PCR显示CK18、α-SMA、vimentin、CD106、nestin基因表达与人骨髓间充质干细胞相似。成骨诱导8天后,碱性磷酸酶表达阳性率100%,19天后骨钙素和一型胶原大量表达,并形成钙结节。结论：所建立的分离培养体系能够获得大量人小涎腺成纤维样单克隆细胞,免疫表型类似于间充质干细胞。在成骨诱导培养条件下具有良好的向成骨细胞分化的潜能。     

脉冲电磁场促进人骨髓间充质干细胞成骨的研究

目的 :观察脉冲电磁场 (PEMFs)对人骨髓间充质干细胞 (hMSCs)成骨能力的影响。方法 :hMSCs受频率 12Hz、场强 1.1mT的PEMFs刺激 8h/d ,检测细胞增殖、细胞周期 ,观察细胞超微结构、骨钙素、Ⅰ型胶原免疫组化染色 ,碱性磷酸酶 (ALP)活性、核固红钙染色。结果 :脉冲电磁场作用后的细胞增殖能力提高 ,细胞形态发生变化 ,透射电镜观察提示细胞成熟 ,核固红钙染色、骨钙素、Ⅰ型胶原免疫组化染色均阳性 ,ALP活性增高。结论 :hMSCs经合理的PEMFs体外刺激后 ,细胞增殖加速 ,符合成骨细胞的形态特征和生物学特性。     

褪黑素对H2O2诱导的成骨细胞氧化应激损伤的保护作用

摘要：目的 探讨褪黑素对H2O2诱导的成骨细胞氧化应激损伤的保护作用机制。方法 取24 h内新生SD大鼠10只，采用组织块贴壁法提取原代成骨细胞并行差速贴壁提纯细胞。细胞传至第2代时行碱性磷酸酶及茜素红染色进行鉴定。将鉴定后的成骨细胞用不同浓度的H2O2作用不同时间并行CCK8试验检测细胞增殖情况。选择合适的浓度和时间建立氧化应激损伤模型，并用褪黑素及EX527进行干预。实验分为对照组、H2O2组、褪黑素组及EX527组。分别对四组细胞行碱性磷酸酶染色、茜素红染色，检测四组细胞活性氧、丙二醛、超氧化物歧化酶含量，同时用流式细胞仪检测四组细胞凋亡率，免疫印迹法检测凋亡相关蛋白Bax、Bcl2和成骨相关蛋白BMP2、RUNX2以及SIRT1和p66SHC的表达量。结果 经鉴定，成功提取原代成骨细胞。CCK8结果显示，400 μmol/L H2O2作用4 h成骨细胞活性降至52 %，适宜用于建立氧化应激损伤模型。H2O2作用后成骨细胞活性及矿化能力降低，ROS含量、MDA含量升高，SOD活性降低，细胞凋亡率升高，伴随有SIRT1、BMP2、RUNX2、Bcl2表达降低，p66SHC和Bax表达升高。褪黑素预处理后缓解了H2O2对成骨细胞的氧化应激损伤作用，部分恢复了成骨细胞的活性及矿化能力，SIRT1抑制剂EX527能够逆转褪黑素的上述作用。结论 褪黑素通过调节SIRT1/p66SHC通路来抑制H2O2诱导的成骨细胞的氧化应激损伤并促进成骨。     

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.     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

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.