Bone tissue engineering is the focus of recent research. Its status quo and tendency are discussed from scaffold, cell and tissue reconstruction. Based on this analysis, we want to shorten the distance before it's clinical application and give some reasonable methods.

The research on war injuries in tropical areas is an important subject to be urgently dealt with at present in Chinese military medicine. Military medicine related to hot and humid environment is a significant branch of military environmental medicine. More efforts should be made in the research on care of war injuries as well as on military hygiene and military epidemiology so as to establish an integrated system involving basic and clinical science and art in military environmental medicine in hot and humid areas, which should be considered as an important task in the transition of our military strategy to win a war with improvement in the military medical support capability in a local high technicology conflict in such an area. In this paper, the significance of paying more attention to the research on the care of war injuries in hot and humid areas is emphasized, their features are highlighted, and main problems demanding further research are proposed.

Tissue engineering has been one of the most challenging and rapidly developing frontier fields of science in the recent 20 years. Being referred to as “a medical revolution of far-reaching significance”, “a new epoch of regenerative medicine”, it signals the coming of a period of reproduction of regenerative tissue and organs. It has drawn intensive attention and support from medical circles and governments all over the world because of its advantages in trauma repair, functional reconstruction, life saving and improving quality of life, as well as its huge social and economic values. Products of tissue engineered skin and cartilage with approval of the American FDA have been available. Hundreds of tissue engineering companies and research centers have been set up both abroad and at home. It is now possible to construct tissue-engineered tissues. Moreover, projects of complex organ construction by means of tissue engineering is being carried out vigorously in the world. Some tissue-engineered tissues have been put into trial use in clinic and resulted in encouraging outcome. All these forecast a bright and promising prospect for tissue engineering. As a new branch of science and technology that involves multiple specialties and fields, however, it is still at its initial stage. Many fundamental scientific problems are to be explored, and many technical difficulties to be overcome. Hope and difficulty coexist; opportunity and challenge stand side by side. We should seize the opportunity and meet the challenge with our creative and strenuous efforts to make tissue engineering benefit human beings as early and much as possible.

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With 20 years’ development, tissue engineering has proceeded to a new stage where the focuses of research are quite different from those at the initial stage. Clinical application and industrial development have been the chief concerns for tissue engineering. After brief comments on the current advances and future prospects, this paper suggests that the future tendencies and strategies will be the primary clinical application, industrial development of tissue engineering products, increasing integration of basic research and clinical application and industrial development, construction of bionic and intelligent tissues or organs, and reliability evaluation. This paper also puts forward some strategies.

OBJECTIVE: Polylactic acid (PLA) is a biodegradable polymer possessing good biocompatibility and biodegradability, and approved as a biomaterial for in vivo implantation by American Food and Drug Administration (FDA). The role of cytokines in promoting osteogenesis and vascularization for constructing tissue-engineered bones has received increasing attention.But exogenous cytokine has shorter half-life in vivo and can not reach and maintain relatively high local level for bone repair. This article reviews the present researches and analyzes the application prospect of PLA and its derivatives in bone tissue engineering to serve as the carrier for polypeptide and protein medicines with controlled release through its degradation.DATA SOURCES: Related articles published between 1993 and 2004were searched in Medline database with key words of "polylactic acid,bone morphogenetic protein, vascular endothelial growth factor, TGF- beta", limiting the language to English; meanwhile the related medical papers between 1993 and 2004 were also searched in the Chinese Periodical Database, limiting the language to Chinese.STUDY SELECTION: Related researches on PLA and its derivatives for constructing bone tissue-engineering Scaffolds and study of PLA scaffolds carrying cytokines were included with the obsolete literature and repetitive researches eliminated.DATA EXTRACTION: Altogether 96 related literatures on PLA and its derivatives for constructing bone tissue-engineering scaffolds were collected, 23 of which were included in this review.DATA SYNTHESIS: PLA/PLA-polyglycolic acid copolymer is a good biodegradable scaffold for controlled drug release, having the dual functions as scaffolds and sustained-release drug carrier. PLA is the earliest scaffold material in bone and cartilage tissue-engineering, and also the most widely used tissue-engineering material at present. BMP is the most frequently adopted cytokine in bone tissue-engineering, and PLA scaffolds carrying sustained-release BMP is studies most thoroughly, but researches on PLA scaffolds carrying vascular endothelia growth factor has not been conducted.CONCLUSION: Development and application of PLA scaffolds carrying various sustained-release cytokines has become the new interest in bone tissue-engineering researches.

Microsurgery has been in a plateau period after a development of 4 decades. Now it has been faced with a difficult situation in China: shrinking scope and increasingly slow development. This may be an inevitable outcome of the spiral rising pattern of development of anything in the world, as well as a combined result of fierce impact of market economy, hysteresis of medical system, ideological deviation and investment deficiency. Recently, however, application of new and high technology, new devices and materials in microsurgery, such as nanometer techniques and materials, gene and tissue engineering, and computerization, has broadened a new development space. Microsurgery in the 21st century should make more efforts in expanding its application dimension, perfecting its therapeutic methods, enhancing basic research, raising technical proficiency of its personnel and improving the welfare of its workers. It should also be nourished with new ideas, interdisciplinary cooperation before it can realize its rejuvenation in the new century.

Vascularization is the basis of tissue regeneration. To get engineered tissue, it is necessary that timely and enough nutrition be available to the seed cells, especially those within the biomaterials. Therefore reconstruction of blood supply is the key step leading from basic research to clinical application. Thee major methods have been used to reconstruct blood supply: promotion of vessel growth by means of VEGF, combined grafting of vascular endothelial cells and osteoblasts and microsurgical techniques. The microsurgical techniques, such as wrapping around with pedicled fascia flap, wrapping around with vascularized muscle flap and blood vessel implanting, can help reconstruct blood supply when engineered tissue is fabricated. When engineered tissue is used in clinic to repair defects in vicinity, vascularization can be done in the defect area. But when no fascia flap, muscle flap or vessel can be used in the defect area, the local defects can be repaired through reconstruction of vascularized engineered tissue in other areas and through second stage transplantation with microsurgical techniques.

Objective This article aimed to describe an interactive segmenting method for serial anatomical cross-sectional image of Chinese Digital Human(CDH) using commercially available software,Photoshop CS(Adobe;San Jose,CA,Corel KnockOut 2.0 plug-in) and Matlab 7.0(Math Works;Worcester,MA). Methods First,the interesting region was segmented from the image interactively utilizing the Knochout menu of Adobe Photoshop which had a powerful masking function.And then smooth contour was acquired precisely by morphological operation function and edge detection operator(the Sobel method) in Matlab. Results The segmentation and classification of bone,muscle and main vascular nerve were fulfilled successfully and the smooth contour lines were acquired with precise details and accurate localization.Conclusion This local clustering segmenting method might segment and classify the colored image of Chinese Digital Human quickly and precisely.