自体骨髓干细胞移植研究进展

细胞移植作为一种新的治疗方法备受医学界关注，但细胞供应短缺和免疫排斥是阻碍这一疗法临床推广的主要难题。自体骨髓干细胞移植在一定程度上可缓解此矛盾。文章综述了自体骨髓干细胞移植治疗脑、肝、心等重要器官疾病的基础和临床研究现状，以及骨髓动员剂在骨髓干细胞移植中的作用。     

姜黄素对肝损伤的保护

目的研究姜黄素对酒精性肝损伤的保护作用。方法采用酒精复制大鼠肝损伤模型，测定肝组织的丙二醛（MDA）、甘油三酯（TG）及还原型谷胱甘肽（GSH）含量；并观察肝脏的病理组织学改变。结果受试样品高、中、低剂量组大鼠肝组织的MDA含量均值分别为16．9、15．5、16．7nmol／g（肝组织），均低于肝损模型组的19．7nmol／g；TG含量分别为2．59、2．67、2．09mmol／100g（肝组织），均低于肝损模型组的4．37mmol／100g；而GSH含量分别为275．6、254．3、307．7μmoL／100g（肝组织），均高于肝损模型组的188．7μmoL／100g；各剂量组大鼠肝脏病理改变评分均值分别为163．3、118．6、162．8分，均低于肝损模型组的253．6分。结论姜黄素对酒精性肝损伤具有保护作用。     

三维超声心动图评价基因转染骨髓干细胞移植治疗慢性缺血心肌价值

目的探讨动态三维超声心动图(DTDE)评价基因转染自体骨髓基质干细胞移植治疗慢性缺血心肌的价值.方法在猪冠脉左旋支放置Ameroid环建立慢性心肌缺血模型;4周后分组注射编码血管生长素(ANG)基因的腺病毒转染的自体骨髓基质干细胞(组Ⅰ)、编码ANG基因的腺病毒液(组Ⅱ)、单纯自体骨髓基质干细胞(组Ⅲ)和空腺病毒磷酸盐缓冲液(组Ⅳ、对照组);再4周后行病理学检查.应用脱机DTDE重建和分析技术,观测正常、置环后4周及注射后4周左室形状、容积和收缩功能的变化.结果慢性缺血心肌左室舒张和收缩末期容积(LVEDV、LVESV)增大,射血分数(LVEF)降低(P<0.01).注射后,对照组LVEDV、LVESV较其它各组明显增大(P<0.05),射血分数(LVEF)明显降低(P<0.05),与缺血时无明显差异(P>0.05).组Ⅰ～Ⅲ较慢性缺血时LVEDV和LVESV均缩小(P<0.05),LVEF均增大(P<0.05),各治疗组比较,左室重构现象均不同程度地减轻,组Ⅰ较其它组,左室容积减小及收缩功能改善最为显著.组Ⅱ和Ⅲ间测值比较无统计学差异.结论DTDE对评价基因转染自体骨髓基质干细胞移植治疗慢性缺血性心脏病具有重要价值.     

大鼠骨髓间质干细胞的分离纯化与鉴定

采用密度梯度离心法分离骨髓间质干细胞,差速贴壁法进行纯化,应用流式细胞仪、激光共聚焦显微镜等对纯化细胞进行鉴定,结果细胞表面抗原CD２９,CD４４,CD１０５,CD１６６表达呈阳性,而CD１４,CD３４,CD４５表达呈阴性。采用RT唱PCR鉴定了三个基因：nestin,NST,Oct唱４,前两者呈阳性表达,后者弱阳性表达。这些细胞特异抗原与基因表达综合起来,表明得到的细胞具备骨髓间质干细胞的特性。密度梯度分离与差速贴壁相结合,可获得较好均一性的骨髓间质干细胞,是一种简单可靠、易于推广的骨髓干细胞获取方法,可为细胞与组织工程研究提供种子细胞。     

经皮恒河猴肝纤维化模型超声引导下肝脏穿刺介绍

目的:观察超声引导下恒河猴肝穿刺活体组织检查技术在动物实验中的应用情况,探讨超声引导下经皮恒河猴肝脏穿刺活检的价值和意义。方法:采用PHILIPS i U22超声仪、9~3 MHz探头、Bard 16G活检枪及活检针对22只恒河猴肝纤维化疾病进行穿刺,对穿刺组织进行病理检查。结果:22只恒河猴均穿刺成功,病理学染色良好,能够进行肝脏疾病的病理分析和诊断。结论:在动物实验中,超声引导下肝脏穿刺活检术是一项微创、安全、方便的取材方法,能确定肝脏损害的病理性质,对实验动物疾病模型诊断和治疗有重要的临床价值。     

人体骨髓基质干细胞冷冻干燥的探索性实验

人体骨髓基质干细胞已成为组织工程、细胞移植和基因治疗等领域的重要研究对象,目前对它已有低温保存的研究,而通过冷冻干燥的方法对其进行保存国内外未见报导.实验尝试用冻干的方法来保存骨髓基质干细胞.文中选取海藻糖、PVP、HES等作保护剂,应用差示扫描量热仪(DSC)测量其结晶温度和玻璃化转变温度;随后对加入保护剂的细胞溶液进行冻干实验,并应用流式细胞仪对冻干样品复水后的细胞活性进行了测定,其中30%PVP 20%海藻糖对细胞的保护效果较好,细胞成活率达到16.40%.     

实时心肌造影在基因转染细胞移植治疗慢性缺血心肌的研究应用

目的用实时心肌声学造影(RTMCE)研究基因转染骨髓基质干细胞移植治疗慢性缺血心肌的效果.方法实验动物(猪)分4组,建立慢性心肌缺血模型4周后,组Ⅰ注射编码血管生长素(ANG)基因的腺病毒转染的自体骨髓基质干细胞,组Ⅱ注射编码ANG基因的腺病毒液,组Ⅲ注射单纯自体骨髓基质干细胞;组Ⅳ(对照组)注射空腺病毒磷酸盐缓冲液.再4周后取心肌组织进行病理学检查.分别于正常状态、慢性缺血心肌模型建立4周和注射后4周开胸时进行RTMCE,选取左室乳头肌水平短轴切面,用闪烁显像观察局部心肌灌注显影情况.实时动态图像存入磁光盘,然后用MCE定量分析软件(CUSQ1.4)分析各阶段心肌灌注图像.结果RTMCE较满意显示了猪慢性缺血心肌基因治疗前后心肌运动和血流灌注状况.经定量软件对闪烁显像心肌再灌注分析,发现慢性缺血心肌模型各组左室侧后壁A值和β值均较正常心肌明显降低(P<0.01),组间比较无明显差异(P>0.05);注射4周后,组Ⅰ、组Ⅱ、组Ⅲ的A值和β值均增高,其中组Ⅰ增高最显著(P<0.01),组Ⅱ和组Ⅲ较对照组亦明显增加(P<0.05),对照组的A值和β值与缺血心肌无明显变化(P>0.05).结论RTMCE及其定量分析软件可对不同血供状态下的心肌灌注进行分析,评价基因治疗慢性缺血心肌的效果.     

后处理对静电纺丝素纤维膜性能的影响

静电纺丝素纤维膜在载药、组织工程及多种电池的研究中具有广泛的应用.静电纺丝素纤维膜在制备过程中,需要后处理以保持纤维的形状及提升纤维膜的性能.本研究以乙醇和甘油对静电纺丝素纤维膜进行后处理,并通过SEM、FTIR、XRD、TGA等表征手段系统研究了不同后处理条件对静电纺丝素纤维膜的结构及性能的影响,并分析及探讨了其影响机制.结果表明:仅用75％(体积分数)乙醇后处理可使丝素蛋白分子β折叠含量增大,纤维膜断裂强度显著增强;仅用甘油后处理可使丝素蛋白分子链无规卷曲度提高,纤维膜的断裂伸长率显著提高,亲水性大大增强;而用75％乙醇结合不同浓度的甘油对静电纺丝素纤维膜进行后处理可调控其力学性能,使其更能满足在不同领域的应用需求.     

英科学家将利用胚胎干细胞3D打印人体器官

<正>据国外媒体报道,科学家离培育重要器官又近一步,不久可能使从人到人的移植成为历史。专家已研发出三维打印技术,可用胚胎干细胞制造人体组织。这种由爱丁堡赫瑞-瓦特大学开发出的方法意味着病入膏肓的病人可轻易获得肝脏、心脏和其他器官。科学家已用这种方法培育出骨髓和皮肤。但他们也开始努力研究可能变成一种新器官的更微妙胚胎细胞结构。他们在实验中用一个可调节"微型阀"制造多层人类胚胎干细胞。改变喷嘴直径可准确控制分配细胞的速度。这些新的打印胚胎细胞保留了变成其他任何细胞类型的能力。     

气相色谱法测定水中乙醇含量方法研究

本文建立直接进样气相色谱法测定水中乙醇含量的分析方法.对进样□温度、柱流速、柱温、分流比进行条件优化,确立了直接进样气相色谱法测定水中乙醇含量的最佳实验条件:升温程序:初始柱温为40℃,保持7min,以20℃/min速率升温至200℃并保持5min;进样口温度:200℃;柱流速:1.0mL/min;分流比:5∶1.该方...     

Effect of supportive extracorporeal treatment in liver transplantation recipients and advanced liver failure patients

Recently, continuous venovenous hemodiafiltration (CVVHDF) and plasmapheresis (PF) were suggested as supportive therapy options in combination with standard treatment in advanced liver failure. The aim of this study was to analyze the effects of supportive extracorporeal treatment (SET) in a group of patients with advanced hepatic failure. A total of 25 patients (7 women, 18 men; mean age, 39.3+/-15.4 years; 13 were transplant recipients [6 women, 7 men; mean age, 37.7+/-16.9 years]) were included. All patients were in hepatic coma and receiving standard coma and liver failure management when they received SET. Number of SET sessions; levels of serum blood urea nitrogen, creatinine, albumin, calcium, phosphorus, ammonia, alanine and aspartate aminotransferase, and total/conjugated bilirubin; and prothrombin times (PTT) before and after SET were recorded retrospectively. 7.7+/-7.9 SET sessions were performed. Thirteen liver transplant recipients required SET for an average of 9.7+/-8.3 days after transplantation. Serum ammonia and bilirubin levels were lower after termination of supportive therapy when compared with initial levels (p<0.0001 and p<0.005 respectively). During follow-up, hepatic encephalopathy and liver failure resolved in 11 patients, while 14 patients (7 transplant recipients) died. There was no significant difference between patients in either group except that PTT was shorter in patients who survived (p<0.01). Further analyses revealed that in surviving patients, ammonia clearance was higher (p<0.01). In patients with advanced liver failure, or liver transplants, CVVHDF and/or PF could be supportive options combined with standard treatment.     

肝脏M型超声图像的包络提取及分析

肝脏在大血管搏动的激励下会产生运动,其运动情况可以反映肝脏硬化的程度,文章利用M型超声技术检测肝脏在这种激励下的运动信息,通过相关技术提取M型超声图像中肝脏的运动包络,并从中提取特性参数,用作肝硬化程度的诊断指标。     

Bioprinting of Multiscaled Hepatic Lobules within a Highly Vascularized Construct

Highly vascularized complex liver tissue is generally divided into lobes, lobules, hepatocytes, and sinusoids, which can be viewed under different types of lens from the micro‐ to macro‐scale. To engineer multiscaled heterogeneous tissues, a sophisticated and rapid tissue engineering approach is required, such as advanced 3D bioprinting. In this study, a preset extrusion bioprinting technique, which can create heterogeneous, multicellular, and multimaterial structures simultaneously, is utilized for creating a hepatic lobule (≈1 mm) array. The fabricated hepatic lobules include hepatic cells, endothelial cells, and a lumen. The endothelial cells surround the hepatic cells, the exterior of the lobules, the lumen, and finally, become interconnected with each other. Compared to hepatic cell/endothelial cell mixtures, the fabricated hepatic lobule shows higher albumin secretion, urea production, and albumin, MRP2, and CD31 protein levels, as well as, cytochrome P450 enzyme activity. It is found that each cell type with spatial cell patterning in bioink accelerates cellular organization, which could preserve structural integrity and improve cellular functions. In conclusion, preset extruded hepatic lobules within a highly vascularized construct are successfully constructed, enabling both micro‐ and macro‐scale tissue fabrication, which can support the creation of large 3D tissue constructs for multiscale tissue engineering.     

Automatic annotation of liver computed tomography images based on a vessel-skeletonization method

Anatomical analysis of liver region is an essential and key step for liver-related disease diagnosis and treatment. One of the challenging issues is to annotate the functional regions of liver automatically or semi- automatically by analyzing Computed Tomography (CT) images. The present study developed a complete liver annotation system with an improved vessel-skeletonization method is proposed for CT images. In the first step, an automatic level set method and a customized region-growing method are applied to extract the liver region including vessels and tumors. Next, a modified iterative thinning method is developed to obtain the geometric structure of liver vessels and mark a vessel skeleton. The three-dimensional information is transformed into a tree data structure for storage. Based on the branch distribution of portal vein skeleton, a model-based method with a modified nearest neighbor segment approximation (NNSA) algorithm is adopted for the functional liver anatomy. Three experiments involving five 64-row liver CT datasets are performed. The accuracies of segmentation and annotation results were validated by an experienced doctor. Compared with different methods, our proposed vessel skeletonization method can simultaneously preserve the connectivity of the vasculature topology and generate the skeleton in a shorter time. Furthermore, our proposed annotation system can provide both visual and measurable information of livers. These experimental results demonstrate the usefulness and effectiveness of our proposed method. Our liver annotation system is helpful to evaluate the function of liver system and support diagnosis of liver disease.     

All Roads Lead to the Liver: Metal Nanoparticles and Their Implications for Liver Health

Metal nanoparticles (NPs) are frequently encountered in daily life, and concerns have been raised about their toxicity and safety. Among which, they naturally accumulate in the liver after introduction into the body, independent of the route of administration. Some NPs exhibit intrinsic pharmaceutical effects that are related to their physical parameters, and their inadvertent accumulation in the liver can exert strong effects on liver function and structure. Even as such physiological consequences are often categorically dismissed as toxic and deleterious, there are cell type‐specific and NP‐specific biological responses that elicit distinctive pharmacological consequences that can be harnessed for good. By limiting the scope of discussion to metallic NPs, this work attempts to provide a balanced perspective on their safety in the liver, and discusses both possible therapeutic benefits and potential accidental liver damage arising from their interaction with specific parenchymal and nonparenchymal cell types in the liver.     

Metabolic interactions of magnolol with cytochrome P450 enzymes: uncompetitive inhibition of CYP1A and competitive inhibition of CYP2C

Magnolol (MAG; 5,5′-diallyl-2,2′-biphenyldiol) is a major bioactive component of Magnolia officinalis. We investigated the metabolic interactions of MAG with hepatic cytochrome P450 monooxygenase (CYP) through in vitro microsomal metabolism study using human (HLM) and rat liver microsomes (RLM). CYP2C and 3A subfamilies were significantly involved in the metabolism of MAG, while CYP1A subfamily was not in HLM and RLM. The relative contribution of phase I enzymes including CYP to the metabolism of MAG was comparable to that of uridine diphosphate glucuronosyltransferase (UGT) in RLM. Moreover, MAG potently inhibited the metabolic activity of CYP1A (IC₅₀ of 1.62?μM) and 2C (IC₅₀ of 5.56?μM), while weakly CYP3A (IC₅₀ of 35.0?μM) in HLM and RLM. By the construction of Dixon plot, the inhibition type of MAG on CYP activity in RLM was determined as follows: uncompetitive inhibitor for CYP1A (K_i of 1.09–12.0?μM); competitive inhibitor for CYP2C (K_i of 10.0–15.2?μM) and 3A (K_i of 93.7–183?μM). Based on the comparison of the current IC₅₀ and K_i values with a previously reported liver concentration (about 13?μM) of MAG after its seven times oral administration at a dose of 50?mg/kg in rats, it is suggested that MAG could show significant inhibition of CYP1A and 2C, but not CYP3A, in the in vivo rat system. These results could lead to further studies in clinically significant metabolism-mediated MAG–drug interactions.     

Thermal conductivity and diffusivity of biomaterials measured with self-heated thermistors

This paper presents an experimental method to measure the thermal conductivity and thermal diffusivity of biomaterials. Self-heated thermistor probes, inserted into the tissue of interest, are used to deliver heat as well as to monitor the rate of heat removal. An empirical calibration procedure allows accurate thermal-property measurements over a wide range of tissue temperatures. Operation of the instrument in three media with known thermal properties shows the uncertainty of measurements to be about 2%. The reproducibility is 0.5% for the thermal-conductivity measurements and 2% for the thermal-diffusivity measurements. Thermal properties were measured in dog, pig, rabbit, and human tissues. The tissues included kidney, spleen, liver, brain, heart, lung, pancreas, colon cancer, and breast cancer. Thermal properties were measured for 65 separate tissue samples at 3, 10, 17, 23, 30, 37, and 45°C. The results show that the temperature coefficient of biomaterials approximates that of water.     

Fe3O4纳米粒子与细胞的相互作用研究

研究10 nm粒径的表面未修饰Fe3O4纳米粒子在体外对人正常肝细胞HL-7702及人肝癌细胞SMMC-7721的生长影响.通过倒置显微镜、透射电镜(TEM)观察加入Fe3O4纳米粒子后肝癌细胞和正常肝细胞的形态变化及磁性纳米粒子在细胞内分布状态.用CCK-8测定加入磁性纳米粒子培养后细胞增殖能力的变化.倒置显微镜、透...