Experiences from tissue microarray in soft tissue sarcomas

The tissue microarray (TMA) technology was introduced in 1998 as a tissue preserving, high-throughput technique that allows studies of multiple markers in large sample sets. TMA slides can be analyzed using techniques such as immunohistochemistry and in situ hybridization and represents a powerful tool for the investigation of potential diagnostic and prognostic markers identified in DNA microarray studies. We review the TMA method, its reproducibility, advantages, limitations and future perspectives with specific focus on soft tissue sarcomas.     

Soft tissue contouring using autologous tissue for hemifacial atrophy

Summary Numerous methods for the restoration of facial symmetry in patients with hemifacial atrophy have been described. Most recently, the use of autologous tissue for augmentation has been employed. Experience gained from the use of free-tissue transplantation with microvascular anastomosis and injection of liposuctioned fat are presented in this paper. In 19 patients, reconstruction was performed using microsurgical tissue transfer, while in 3 patients, autologous fat transplantation alone was used. Indications, operative techniques together with the advantages as well as disadvantages associated with each procedure are described.     

引导组织再生术用于牙周组织再生的影响因素

1982年Nyman S首先提出了引导组织再生（Guided Tissue Regeneration，GTR）的概念。引导组织再生的基本原理是用外科的方法放置一个物理屏障来选择性地分隔不同的牙周组织，即就是阻止牙龈结缔组织来源的成纤维细胞首先与根面接触，在膜与牙根之问形成楔状间隙，引导牙周膜细胞向冠方迁移生长，形成真正的牙周再生。随着GTR膜材料研究的不断深入，     

经RNM诱导的前脂肪细胞构建组织工程化脂肪组织

目的:应用基因工程和组织工程的原理和方法,通过改造人前体脂肪细胞,提高其活性后,于裸鼠背部皮下构建组织工程化脂肪组织.方法:采用原代消化细胞培养法培养出前脂肪细胞,利用RNAi技术,诱导前脂肪细胞内的一个重要凋亡调控基因Bax基因表达沉默,然后接种到聚乳酸一乙醇酸共聚物(PLGA)支架上,种植在20只雌性裸鼠皮下,对获得的脂肪组织进行组织学评价.结果:经过改造后的前脂肪细胞活性良好,术后裸鼠全部成活,前脂肪细胞能够在支架上良好的存活,生长和增殖.结论:经过改造后的前脂肪细胞具有良好的活性,并且PLGA-前脂肪细胞复合体在裸鼠体内可形成脂肪细胞,值得进一步研究,以探索治疗软组织缺损的新途径.     

Influence of tissue nitration on tissue damage with thermal injury

A gas mediator, nitric oxide, is converted into peroxynitrite in the presence of superoxide anion. Peroxynitrite is a potent oxidant, which injures various tissues and organs by nitration of tyrosine residue in protein and enhances the inflammatory response in the prolonged phase. In this study, the authors investigated the relationship between peroxynitrite-mediated tissue nitration and tissue damage with thermal injury using an experimental burn model. The content of nitrotyrosine in the burned tissue significantly increased 1 to 6 h after injury. The nitrotyrosine content in the burned ear significantly decreased with 100 mg/kg of LNAME administration. Vascular hyperpermeability was also significantly suppressed in the iNOS antibody immunoneutralized mice 6 h after injury. There was a positive correlation between the severity of tissue damage, an indicator of which is the increase in the weight of the burned ear along with the development of edema after injury, and the concentration of nitrotyrosine in the wound tissues. Nitrotyrosine-like immune reactants were also diffusely detected in the burned region and the surrounding areas. These results indicate that peroxynitrite is produced in the surrounding burned region and a reaction of nitration of tissue tyrosine is involved with tissue damage at the burn wound. Therefore, to prevent the systemic vascular hyperpermeability and tissue damage in a large area burn or severe burn patients, the administration of NOS inhibitors or radical erasers may be easy to manage generally by inhibition of peroxynitrite formation.     

Noninvasive tissue oximetry

Noninvasive tissue oximetry is playing an important role in postoperative monitoring of autologous tissue breast reconstruction flaps. It is increasingly being used intraoperatively to assist in perforator selection, tissue mapping, and assessment of mastectomy skin flap viability. This article reviews the use of tissue oximetry for intraoperative decision making, flap physiology, and postoperative monitoring, and also comments on common flap complications.     

Adipose tissue fibrosis

The increasing prevalence of obesity causes a major interest in white adipose tissue biology. Adipose tissue cells are surrounded by extracellular matrix proteins whose composition and remodeling is of crucial importance for cell function. The expansion of adipose tissue in obesity is linked to an inappropriate supply with oxygen and hypoxia development. Subsequent activation of hypoxia inducible factor 1 (HIF-1) inhibits preadipocyte differentiation and initiates adipose tissue fibrosis. Thereby adipose tissue growth is limited and excess triglycerides are stored in ectopic tissues. Stressed adipocytes and hypoxia contribute to immune cell immigration and activation which further aggravates adipose tissue fibrosis. There is substantial evidence that adipose tissue fibrosis is linked to metabolic dysfunction, both in rodent models and in the clinical setting. Peroxisome proliferator activated receptor gamma agonists and adiponectin both reduce adipose tissue fibrosis, inflammation and insulin resistance. Current knowledge suggests that antifibrotic drugs, increasing adipose tissue oxygen supply or HIF-1 antagonists will improve adipose tissue function and thereby ameliorate metabolic diseases.     

Experimental studies on tissue injury by microwave tissue coagulator]

The tissue injury caused by Microwave Tissue Coagulator (MTC) was assessed clinically and experimentally with dogs. Following hepatic transection using MTC on condition that the output was 60 watts and radiation lasted for 60 seconds at one time, GOT, GPT, lactic acid, FDP and endotoxin concentration increased and coagulation parameters such as hepaplastin test were deteriorated transiently. Of tissue injury, following results were obtained. 1) The mechanism of tissue injury by MTC consists of direct heat injury and infarct by circulatory disturbance. The extent of injury from the needle electrode is approximately 10 mm in the former mechanism and 20mm in the latter. 2) Injury of vessels in Glisson's sheath was confirmed up to 50mm apart from the needle electrode by labelling index of bromodeoxyuridine in bile duct epithelial cells. 3) The granulation formation at the site of necrosis was considerably retarded by wound infection. Accordingly, when MTC is utilized on hepatectomy, followings should be noted: 1) To prevent the large intrahepatic vessels from heat injury, MTC may be utilized at the surface of the liver and the needle electrode must be punctured more than 10mm apart from them. 2) Bile leakage at the resected stump should be eliminated to prevent infection at the stump.     

Hepatic tissue engineering

Fulminant hepatic failure (FHF) attributes to rising medical cost and accounts for many deaths each year in the United States. Currently, the only solution is organ transplantation. Due to increasing donor organ shortage, many in need of transplantation continue to remain on the waiting list. Liver Assist Devices (LADs) are being used to temporarily sustain liver function and bridge the period between FHF and transplantation. Hepatic Tissue Engineering is a step toward alleviating the need for donor organs; yet many challenges must be overcome including scaffold choice, cell source and immunological barriers. Bioreactors have aided in hepatocyte survival and have proven to sustain viable cells for several weeks. Achieving the necessary functions required for hepatic replacement is aided by the incorporation of growth factors and mitogens many that now can be bound to the polymer scaffold and released in a timely manner. Utilizing concepts such as MicroElectroMechanical systems (MEMs) technology, our laboratory is able to mimic the natural vasculature of the liver and sustain functional and viable hepatocytes. Expanding and improving upon this platform technology, advancements made will continue toward the development of a fully functioning and implantable liver.     

组织工程骨软骨复合组织构建研究进展

本文综述了近几年骨软骨组织工程研究进展。查阅近几年有关骨软骨组织工程的文献,于支架材料、信号因子、种子细胞及制备技术等方面加以总结分析。骨软骨组织工程根据仿生学理论与方法完成组织替代物的制备并对损伤或有缺陷组织进行修复,可有效恢复受损骨软骨组织的结构功能与力学特性,是一种具有长远意义的综合交叉学科。目前,骨软骨组织工程策略针对骨软骨损伤取得了一定的成果,但仍需进一步发展,最终为骨软骨损伤提供一种成熟的临床治疗方法。     

Distribution of thymic tissue in the mediastinal adipose tissue.

The distribution of thymic tissue in the anterior mediastinal, retrocarinal, and preaortic fat was examined histologically in 27 autopsy subjects. Thymic tissue was found in the anterior mediastinal fat in 12 subjects (44.4%), in the retrocarinal fat in two (7.4%), and in the preaortic fat in none. The finding of ectopic thymic tissue in these areas has not been reported previously, would appear to be surgically inaccessible via a median sternotomy, and may be responsible in part for some of the failures of thymectomy in the treatment of myasthenia gravis.