Biologic scaffold materials derived from decellularized tissues and organs have been successfully used in tissue engineering and regeneration medicine.Decellularization methodology varies according to the differences of the origin,tissue density,composition,geometric and biologic properties of the tissue.Optimal decellularization method should be developed on the basis of complete cell content removal with the preservation of extracellular matrix (ECM) integrity and bioactivity.In this article,an overview of decellularization methods and their effect upon acellular bracket structure and composition are presented.

A nice biomaterial,which could replace the correlated tissue or organic of human body,supports the homologous function of organism,and accelerates the process of self recovery and autotherapy in the same time.The application of biomaterial in clinic,not only have the chemical characters and function of vitodynamics to match,but also be with nice biocompatibility and practical safety.Some development of biomaterial and the biocompatibility of it in this paper was reviewed,and the application status in the cardiothoracic surgery in recent years.

With the development of the cross-correlation technique in surgery, the transplantation and vi-cariousness have become more and more important in repair surgery and reconstructive surgery. A nice bio-material could replace the related tissue or organ of human body, support the homologous function of organ-ism,and accelerate the process of self recovery and autotherapy. This review is about the status of research and application of biomaterial in surgery.

Despite solitary pulmonary nodule (SPN) is a common medical problem in the clinic,the managements can be quite complex.The aetiological agent is largely unknown.Making a definitive diagnosis for SPNs before the operation has been a clinical challenge.A major problem for clinicians and radiologists were to identify the nature of benign and malignant SPNs at an early stage,and let the patients receive therapies timely and effectively.At present,many clinical features and detect methods of SPNs have been applied for differentiating the nodules,but these are not fully to distinguish it.Recently,some progressions had brought qualitative improvements to the diagnosis and treatment of SPNs.Therefore,in this paper,the research status and progresses of SPNs were reviewed.

One of the key contents in tissue engineering trachea replacement research is the scaffold selection.This review summarizes the latest original literatures and investigations about electrospun technique as well as recent progress.To discuss the advantages and disadvantages of natural,synthetic and combined electrospun scaffolds,the versatility in material choosing and production methods is the unique superiority.For specific experimental or clinical objects,the further research is to choose a suitable polymer,to improve surface modification techniques and to control the dimension and arrangement of the fibrous structure of electrospun fibers,which can offer versatility and tissue specificity,and therefore provide a bright prospect for tissue engineering trachea.

There is a high incidence of esophageal cancer(EC) in China.The survival and prognosis of EC is unoptimistic due to the lack of efficient early diagnostic markers.There is an urgent demand of novel biomarkers with more stability,sensitivity and specificity.miRNAs are a class of small non-coding single stranded RNAs consisting of 21-23 nucleotides,which are involved in the pathological and physiological process of life activities.miRNAs are stable not only in tumor tissues,but also in serum/plasma.There are significant differences in the expression patterns of circulating miRNAs between two main types of EC.They are closely related to the occurrence and progression of EC,which make circulating miRNAs a novel kind of biomarkers for differential diagnosis,early supervision of esophageal cancer,and prognosis.

Objective: To investigate the feasibility of tracheal prosthesis made from biomaterials in the replacement of the circumferential tracheal defects. Methods: Surgical resection and replacement of the cervical trachea with different prosthesis was performed in 16 mongrel dogs. Bronchoscopic, roentgenographic, macroscopic and histopathologic examinations were employed to evaluate the efficacy of the tracheal substitutes. Results: In group A (with type-I prosthesis, n=8), one dog died from prosthetic dehiscence on 96th days postimplantation, another one died from anastomotic leakage caused by severe infection in cervical incision on postoperative 45th days. The other 6 of group A had uneventful postoperative courses and did not show any respiratory symptoms. Tracheal prostheses were completely healed with the recipient's trachea and combined in its integrity. Varied degrees of epithelial lining were observed to have formed near both the anastomotic ends. In addition, many scattered and varied sizes of neo-ossification substances were found at the sites surrounding implanted prostheses. In group B ( type-II prosthesis ,n=4), dehiscence and dislocation of implanted prostheses often occurred with time after operation, which inevitably resulted in severe and fatal postoperative complications .In group C (type-III prosthesis, n=4), all 4 dogs died within 28 days after operation. The leading causes of death were mesh exposure, collapse, infection and air leakage from implanted prosthesis itself. Conclusion: Type-I tracheal prosthesis is a suitable alternative method in reconstruction of tracheal defects, which appears very promising for the clinical application, with further improvements in promoting the epitheli alization completely.

In recent years,Scientists paid close attention to the studies and applications of tissue-engineered trachea,which have made some advances.But how to promote tissue-engineered trachea for clinical application still needs deeper research.Here we discussed from three key aspects of tissue-engineered trachea (Scaffold,Cell,Bioreactor),which attempted to retrospect the current progress in tissue-engineered trachea and provided a guidance of further investigations.

BACKGROUND: Preparing the tracheal prosthesis by biomaterials is crucial for studying the implant of long tracheal defect.The biocompatibility and biodegradability of collagen/hydroxyapatite (Col/HAp) and poly(lactic-co-glycolic acid) (PLGA) in vivo, as a artificial material for tracheal prosthesis, need to be observed.OBJECTIVE: To explore in vivo biodegradability of Col/HAp and PLGA of tracheal prosthesis in rats.DESIGN: Randomized controlling observation.SETTING: Department of Thoracic and Cardiovascular Surgery, Clinical College of Yangzhou University; Department of Thoracic and Cardiovascular Surgery, Changzheng Hospital of the Second Military Medical University of Chinese PLA.MATERIALS: The experiment was carried out in the National Experimental Animal Center of the Second Military Medical University of Chinese PLA from March 2003 to December 2004. Sixteen SD rats of either gender were offered by this center, aged three months and weighed 150-170 g. Col/HAp and PLGA (the copolymer of polylactic acid and polyglycolic acid according to the percent of 90:10) were self-made.METHODS: ①Empirical process: Rats were fed adaptively for 1 week and anesthetized. Then undermining dissection was performed along with musculi dorsal surface toward spine bilaterally, so as to form two capsular gaps, which were implanted with Col/HAp sponge and PLGA fiber mesh cloth respectively, in a size of 10 mm ×10 mm. ②Empirical evaluation: The postoperative activity, incision healing and rejection of rats were observed; 2, 4, 6, 8 weeks postoperatively, the Col/HAp sponge and PLGA mat that were embedded subcutaneously as well as surrounding tissues were determined using scanning electron microscope or transmission electron microscope.MAIN OUTCOME MEASURES: In vivo biodegradability of two materials implanted in rats at different time points.RESULTS: ①All the animals could carry out normal activity, respiration and diet; no incision infection, fluidity, necrosis or sinus tract appeared; there was no edema in the skins of implanted area, neither hypersensitiveness nor toxicity was found; the implant materials had no rejection. ②The features of the implanted materials varied throughout the implantation. During the follow-up, the infiltration of inflammatory cells was found in the interface between the implants and neighboring host tissues in the early stage, phagocytes and fibroblastic cells were also observed later. As the process went on, the materials were biodegraded gradually, encapsulated by phagocytes, and replaced by newly generated fibrous tissues. No remarkable harmful influences of the composite materials on the neighboring host tissues such as apomorphosis, necrosis, hyperplasia and foreign body reaction were observed grossly and microscopically.CONCLUSION: All the implants show a good biocompatibility and biodegradability. Both Col/HAp and PLGA go through a gradual process of biodegradability, biological absorption and replacement by host tissues ultimately in vivo, which suggest that these two kinds of composite biomaterials will be used safely in developing tracheal prosthesis.

Resection of the trachea for more than half of its length requires implantation of an artificial trachea to allow safe reconstruction. The article introduced the recent progress on tissue engineered trachea.The problems encountered in this field and the study direction in the future are also mentioned.