组织工程学研究现状及前景

１９世纪 ４０年代现代外科学奠基以来,对外科病的治疗主要采用病变组织切除及重建术。自体组织移植是以牺牲健康组织为代价的,虽然临床效果满意,但增加了病人的创伤,且供区极为有限;有血供的同种异体组织移植尚少有成功的报道。为挽救生命的同种异体器官移植随着对移植免疫研究的深入,目前已有心、肺、肝、肾等实质器官移植长期成活的报道。然而供器官的严重不足,使不少病人在等待器官移植中死亡。２１世纪８０年代,由Ｌａｎｇｅｒ和Ｖａ－ｃａｎｔｉ提出的组织工程学是利用工程学和生命科学的原理和技术,在体外预先构建一个有生…     

组织工程学研究现状及发展趋势

创伤与病损组织的修复一直是医学界的难题之一,长期以来国内外学者进行了大量相关研究与临床实践。近年来,随着细胞生物学和生物材料科学的发展,组织工程学作为高新技术领域的一门多学科交叉的新兴边缘学科随之应运而生,并得到了迅速的发展。利用组织工程学方法和手段修复组织缺损是一种全新的治疗模式,具有广阔的应用前景,是目前医学界研究的热点问题。1　组织工程学的概念及特点对于创伤与病损组织的修复重建,现行的许多方法主要有异体移植、同种异体移植、人工合成替代物等,但均存在一定问题和缺陷:免疫排斥反应、自体移植其供区有限、人…     

分子生物学在组织工程学研究中的应用前景

近几年来 ,分子生物学在组织工程学各研究领域中的应用越来越广泛 ,其地位和影响越来越重要。我们对这一进展进行了综述 ,并提出了”分子组织工程学”这一概念。一、组织工程学亟待解决的问题组织缺损或器官功能障碍是人类保健中发生最频繁、危害性最大、花费最高的问题之一。人们通过器官移植、外科重建及诸如肾透析之类的机械装置虽然取得了一些效果 ,但还存在许多问题。12年前 ,随着生命科学与工程学的飞速发展 ,一门崭新的交叉学科———组织工程学 (ｔｉｓｓｕｅｅｎｇｉｎｅｅｒｉｎｇ)诞生了。它是应用工程学和生命科学的原理和方法…     

老年人骨再生的组织工程学研究

人体骨骼有支持、运动、保护、造血及钙储存等多方面的功能。骨组织时刻处于骨重建的动态变化之中 ,即不间断的骨形成、骨吸收贯穿于人生命的始终。骨重建受多因素的交互作用 ,这些因素包括成骨细胞、破骨细胞、激素、生长因子和细胞因子 ,最终达到骨结构的稳定和钙的系统性平衡。生命早期 ,成骨活动及破骨活动共同保证了骨吸收与形成间的平衡。随着年龄的增长 ,成骨细胞的分化、活性和寿命都有下降 ,而破骨活动没有明显改变或者增强 ,最终由于骨吸收与形成间的失衡造成骨质疏松。笔者对可能造成老年人骨再生能力下降的因素作一回顾 ,并介绍…     

骨骼肌肉系统组织工程学研究

组织工程学是近十几年提出的新概念 ,它的科学意义不仅在于为病人解除痛苦提供了一种新的治疗方法 ,更重要的是提出了复制“组织”、“器官”的新思想 ,因此一经提出 ,即受到各国政府、科学家、企业界人士的极大重视。我们自 1 992年开始 ,从骨骼肌肉系统着手 ,对骨、软骨、肌腱、周围神经、肌肉等进行了组织工程学研究。1　骨组织工程研究1 .1　种子细胞从骨髓中分离培养基质干细胞。由于干细胞具有多分化潜能 ,可在一定条件下向成骨细胞转化 ,是构建组织工程化骨组织的重要细胞 ,且骨髓可从患者的髂骨穿刺获得 ,因此最有可能作为自体细胞…     

加快组织工程学临床基础研究的步伐

组织工程学已有 10多年的发展历史,由于提出了“体外复制组织 (器官 )”的新思想,使组织工程学研究不仅具有重要的科学意义,同时也具有潜在的经济效益。我国开始组织工程学研究的起步时间与国外相近,不少研究成果的水平与国外相当,在某些领域已达国际领先水平。如何发挥我国的特色,加快组织工程学基础研究的步伐,尽快将其应用于临床实践,将是广大科研工作者与临床工作者共同努力的方向。 一、骨骼、肌肉系统的组织工程学研究现状 我国对骨骼、肌肉系统的组织工程学研究主要集中在骨、关节软骨、肌腱、肌肉和周围神经方面。骨组织…     

组织工程学研究进展

由于创伤、先天性疾病、癌症、感染、炎症等原因所造成的组织与器官的缺损日渐增多。目前，临床上常采用自体、同种异体或异种组织器官进行移植修复，但仍因供源不足、造成供体受损及免疫排斥等问题而难以满足临床需求。近十几年来，组织工程学（tissue engineering）的兴起和发展为解决这一难题提供了新思路和手段。组织工程学是应用生物学和工程学的原理，在正确认知哺乳动物正常及病理两种状态下组织结构与功能关系的基础之上，研究开发能够修复、维持或改善损伤组织功能的生物替代物的一门科学。     

Composite Tissue Allotransplantation: Current Challenges

Composite tissue allotransplantation (CTA) in the clinic is taking firm root. Success at hand, face, knee, trachea, and laryngeal transplantation has led to widespread interest and increasing application. Despite this, skepticism is common, particularly in the realm of reconstructive surgeons. The risks of immunosuppression remain a barrier to the advancement of the field, as these are perceived by many to be prohibitive. Significant progress in the field require the development of newer immunosuppressive agents with less toxicity and methods to achieve donor specific tolerance. This review focuses on the current state of CTA—both in the clinic and the laboratory. A thorough understanding of the immunology of CTA will allow the widespread application of this promising field.     

骨组织工程临床研究现状与展望

时至今日,组织工程研发的部分医疗产品已走上临床,美国已有多种组织工程皮肤和软骨产品实现规模化生产和上市销售;符合了生长因子的骨修     

Composite Tissue Allotransplantation (CTA): Current Status and Future Insights

Approximately 7 million individuals (over 1 million amputees) require complex reconstructive procedures in the United States each year. The recent success of clinical composite tissue allotransplantation, attests to the fact that composite tissue allografts have tremendous potential in these life-enhancing reconstructions. This review summarizes the initial outcomes of the first four human hand transplants, together with those of the first larynx, bone, knee, nerve and tendon transplants, with special emphasis on the operative technique, graft survival and functional outcomes. The May 2000 Louisville symposium, where these results were presented was undoubtedly a milestone in the history of modern composite tissue allotransplantation. It set the stage for reconstructive and transplant surgeons, researchers, physiotherapists, patients and patient advocates and members of the community to convene and discuss major advances in current composite tissue allotransplantation. The symposium underscored the vital importance of objective evaluation of the status of composite tissue allotransplantation by frank dissemination of details of clinical results and complications of the transplants performed thus far. The composite tissue allotransplantation area is among the newest of transplant areas. The immunology of composite tissue allografts is complex, making tolerance more difficult to achieve than organ tolerance. It needs to be emphasized that any episodes of acute rejection should be prevented for perfect restoration of function and to minimize the risk of chronic rejection in composite tissue allografts. Efficacious, safe and ethical clinical tolerance protocols could improve patient acceptance of composite tissue allografts by providing an alternative to chronic immunosuppression.     

Diagnosis of Tuberculosis in Camelids: Old Problems,Current Solutions and Future Challenges

In spite of great efforts for its control and eradication, tuberculosis remains one of the most important zoonosis worldwide. Its causative agents, the members of the Mycobacterium tuberculosis complex, have a wide host range that complicates the epidemiology of this disease. Among susceptible species to these pathogens, camelids from the New World (llama, alpaca and vicuña) and Old World (Bactrian camel and dromedary) are acquiring an increasing importance in several European countries because of its growing number and could act as reservoirs of the disease for livestock and humans in their natural habitat. In addition, tuberculosis caused by a number of M. tuberculosis complex members is a life‐threatening disease in these animal species. Although tuberculosis has been known to affect camelids for a long time, ante‐mortem diagnosis is still challenging because of the lack of standardized diagnostic techniques and the limited sensitivity and specificity of the most widely applied tests. However, in recent years, several techniques that can at least partially overcome these limitations have been developed. This paper reviews the results and advances achieved in tuberculosis diagnosis in camelids in the last decade as well as the progresses on ongoing investigations, with special attention to the remaining challenges that still have to be faced to assure the availability of reliable tools for the detection of tuberculosis‐infected animals and herds.     

Current and Future Challenges in the Surgical Treatment of Hepatocellular Carcinoma: A Review

Challenges in the treatment of hepatocellular carcinoma Hepatocellular carcinoma (HCC) represents one of the most frequent types of cancer worldwide. Surgery, although only a part of the armamentarium against HCC, represents the cornerstone in the management of this aggressive disease. This article will review the current and future challenges in the surgical management of HCC, with a special emphasis on the following areas: (1) the evolution of staging of the disease and the importance of the biological nature and behavior of HCC, (2) the effort to increase resectability, (3) technical innovations and the role of image-guided surgery, and, finally, (4) the role of liver transplantation in the continuum of care for these patients. Although by no means an exhaustive list, the issues mentioned above represent some of the most promising prospects for significant progress in the management of HCC.Key words: Hepatocellular carcinoma, Image-guided surgery, Liver transplantation, ResectabilityThe incidence of hepatocellular carcinoma (HCC) has risen significantly in the United States in the last decade, only to be surpassed by the increased incidence in East Asia and sub-Saharan Africa because of the high prevalence of hepatitis B in that area.^1,2 In other parts of the world, such as North America, Europe, and Japan, the main culprit appears to be the high prevalence of chronic hepatitis C infection, together with confounding factors, such as alcohol abuse, nonalcoholic steatohepatitis, obesity, and tobacco use.^3–5 The common theme is the association between liver cirrhosis and HCC, with 80% of HCC cases being in cirrhotic livers.⁶ Although the exact mechanism has not been fully elucidated yet, it may have to do with changes in the normal hepatic architecture seen in cirrhosis or with damage caused by the viral DNA in the cases of hepatitis infection, both representing a cancerous transformation signal.Given the complexity of the disease, it should come as no surprise that its treatment is multimodal and requires the cooperation of multiple specialties. Even so, surgery remains the cornerstone of the management of HCC, as it has the unique ability to provide a therapeutic option. The 2 main curative surgical therapies are liver resection and orthotopic liver transplantation (OLT). Even with careful patient selection, recurrence and metastatic disease remain the 2 main problems encountered in liver resection, with OLT having to deal with the additional obstacle of the limited number of available donors. Other treatments, such as chemoembolization or radiofrequency ablation, may be able to limit the disease in certain situations or act as bridging therapies, although overall the results cannot be compared with those of resection or OLT. The limitations mentioned above serve to underscore the challenges facing hepatic surgery, as well as to identify the areas where the research efforts should be focused. In this article, the areas that will be reviewed represent promising prospects for progress in the surgical management of HCC.