中药保健再生纤维素纤维的开发及应用

为开发中药保健纤维素纤维,结合中药提取物技术,研究中药保健再生纤维素纤维的制备技术,介绍其工艺流程和生产工艺特点。重点对该类纤维的形态结构、物理机械性能、抗菌性能及纤维性能特点进行分析,同时,对中药保健再生纤维素纤维的开发应用领域进行分析,并提出该类产品制备技术的两大发展趋势,包括微胶囊化技术和吸附材料微粒化技术,为中药保健再生纤维素纤维的开发和生产提供参考。

美国NASA高级生保计划实验模型项目研究进展

美国NASA肯尼迪空间中心的高级生保计划实验模型项目着重进行生物再生生保部件的研制 ,目的在于进行大气、水和食物生产的作物栽培以及用于废物循环的生物反应器的研制等。该项目的中心部件是生物量生产舱 ,外围 1 5个环境受控舱和占地面积为 2 1 50m2 的实验设施。为了支持高级生保计划 ,该项目已经并将继续利用这些装备进行大规模的部件试验和所需相关技术的开发 ,以便应用于位于NASA约翰逊空间中心的载人试验基地 ,以期最终实现月球和火星飞行。

Regenerative Engineering for Knee Osteoarthritis Treatment： Biomaterials and Cell-Based Technologies

Knee osteoarthritis （OA） is the most common form of arthritis worldwide. The incidence of this disease is rising and its treatment poses an economic burden. Two early targets of knee OA treatment include the predominant symptom of pain, and cartilage damage in the knee joint. Current treatments have been beneficial in treating the disease but none is as effective as total knee arthroplasty （TKA）. However, while TKA is an end-stage solution of the disease, it is an invasive and expensive procedure, Therefore, innovative regenerative engineering strategies should be established as these could defer or annul the need for a TKA. Several biomaterial and cell-based therapies are currently in development and have shown early promise in both preclinical and clinical studies. The use of advanced biomaterials and stem cells independently or in conjunction to treat knee OA could potentially reduce pain and regenerate fo- cal articular cartilage damage. In this review, we discuss the pathogenesis of pain and cartilage damage in knee OA and explore novel treatment options currently being studied, along with some of their limitations.

Liver bioengineering:Current status and future perspectives

The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The first consists of creating a supporting scaffold,either synthetically or by decellularization of human or animal organs,and seeding cells on the scaffold,where they will mature either in bioreactors or in vivo.This strategy seems to offer the quickest route to clinical translation,as demonstrated by the development of liver organoids from rodent livers which were repopulated with organ specific cells of animal and/or human origin.Liver bioengineering has potential for transplantation and for toxicity testing during preclinical drug development.The second possibility is to induce liver regeneration of dead or resected tissue by manipulating cell pathways.In fact,it is well known that the liver has peculiar regenerative potential which allows hepatocyte hyperplasia after amputation of liver volume.Infusion of autologous bone marrow cells,which aids in liver regeneration,into patients was shown to be safe and to improve their clinical condition,but the specific cells responsible for liver regeneration have not yet been determined and the underlying mechanisms remain largely unknown.A complete understanding of the cell pathways and dynamics and of the functioning of liver stem cell niche is necessary for the clinical translation of regenerative medicine strategies.As well,it will be crucial to elucidate the mechanisms through which cells interact with the extracellular matrix,and how this latter supports and drives cell fate.

Evaluation of rutting and low-temperature cracking resistancesof warm-mix recycled asphalt bindersunder the secondary aging condition

The rutting and low-temperature resistances of warm-mix recycled asphalt binders under the secondary aging condition were measured by the dynamic shear rheometer test and bending beam rheometer test.Effects of different types of warm-mix asphalt(WMA)technologies and additives were evaluated.Aging and improvement mechanisms were investigated by the Fourier transform infrared spectroscopy test.It is found that recycled binders after the secondary aging are more resistant to rutting and less resistant to low-temperature cracking.The two warm-mix asphalt technologies have opposite effects.Using the Sasobit WMA significantly improves the rutting resistance and reduces the low temperature resistance for the recycled binders due to its morphological change at different temperatures.The rutting factor values of recycled asphalt binders with the Sasobit additive increase by 4.6 to 5.6 times.However,using the Evotherm WMA causes the deterioration of the rutting resistance due to the structural lubrication effect.The rutting factor values of recycled asphalt binders with the Evotherm additive show the reduction of 52%to 62%.It is recommended to add the styrene butadiene rubber latex or crumb rubber powder into the warm-mix recycled asphalt binders to simultaneously improve the rutting and low-temperature cracking resistances.

4-Axis printing microfibrous tubular scaffold and tracheal cartilage application

Long-segment defects remain a major problem in clinical treatment of tubular tissue reconstruction.The design of tubular scaffold with desired structure and functional properties suitable for tubular tissue regeneration remains a great challenge in regenerative medicine.Here,we present a reliable method to rapidly fabricate tissueengineered tubular scaffold with hierarchical structure via 4-axis printing system.The fabrication process can be adapted to various biomaterials including hydrogels,thermoplastic materials and thermosetting materials.Using polycaprolactone(PCL)as an example,we successfully fabricated the scaffolds with tunable tubular architecture,controllable mesh structure,radial elasticity,good flexibility,and luminal patency.As a preliminary demonstration of the applications of this technology,we prepared a hybrid tubular scaffold via the combination of the 4-axis printed elastic poly(glycerol sebacate)(PGS)bio-spring and electrospun gelatin nanofibers.The scaffolds seeded with chondrocytes formed tubular mature cartilage-like tissue both via in vitro culture and subcutaneous implantation in the nude mouse,which showed great potential for tracheal cartilage reconstruction.

Researches on regenerative medicine current state and prospect

Since 1980s, the rapid development of tissue engineering and stem cell research has pushed regenerative medicine to a new fastigium, and regenerative medicine has become a noticeable research field in the international biology and medicine. In China, about 100 million patients need repair and regeneration treatment every year, while the number is much larger in the world. Regenerative medicine could provide effective salvation for these patients. Both Chinese Academy of Sciences and Chinese Academy of Engineering have made roadmaps of 2010-2050 and 2011-2030 for regenerative medicine. The final goal of the two roadmaps is to make China go up to leading position in most research aspects of regenerative medicine. In accord with this strategy, the government and some enterprises have invested 3-5 billion RMB （0.5-0.8 billion USD）for the research on regenerative medicine. In order to push the translation of regenerative medicine forward -- from bench to bedside, a strategic alliance has been established, and it includes 27 top-level research institutes, medical institutes, colleges, universities and enterprises in the field of stem cell and regeneration medicine. Recently the journal, Science, has published a special issue-Regenerative Medicine in China, consisting of 35 papers dealing with stem cell and regeneration, tissue engineering and regeneration, trauma and regeneration and bases for tissue repair and regenerative medicine. It is predicated that a greater breakthrough in theory and practice of regenerative medicine will be achieved in the near future （20 to 30 years）.