In recent years,pharmacological researches of Chinese medicine found that the single Chinese medicines of activating blood and dissolving stasis,such as Drynaria and Bidentata and Salvia and Panax notoginseng had very good effects of resisting osteoporosis,significantly improving bone mineral density(BMD)and bone mineral content(BMC),promoting bone formation,and preventing bone absorption.Based on the documentations from home and abroad,the overview had analyzed the current situation for providing new ideas and methods of osteoporosis prevention and treatment.

In recent years, pharmacological researches of Chinese medicine have found that single Chinese exterior-relieving medicines such as Pueraria, Semen Sojae Praeparatum and Cimicifuga had very good anti-osteoporosis effect. They can significantly improve the bone mineral density (BMD) and bone mineral content(BMC), promote bone formation, and prevent bone absorption. Based on relative documents from home and abroad, this paper analyzed the current situation and provided new ideas and methods for prevention and treatment of osteoporosis.

[Objective] To establish an effective and stable method to induce hematopoietic cells from embryonic stem(ES) cells,the phenotype and function of ES-derived hematopoietic cells induced by stromal cell conditioned medium (SCCM) of yolk sac (YS),fetal liver (FL) or bone marrow (BM) were analyzed and compared.[Methods] 10% of YS-SCCM,FL-SCCM or BM-SCCM was added to culture system for differentiation of ES cells.Flow cytometric analysis was used to identify expression of Flk1,Integrin α4,Sca-1,and CD34.Colony analysis was used to identify the quantity of high proliferative potential colony-forming cells (HPP-CFC) in differentiated ES cells.The yield of CFU-S (colony-forming unit-spleen) was also analyzed by transplanting ES cell derivatives into lethally irradiated mice.[Results] Expression of Flk1,Integrin α4,Sca-1,and CD34 could be tested on induced EB cells.The percentage of Flk-1+,Integrin α4+ and Sca-1+ cells induced by were 3.03%,2.9%,and 13.74%,respectively,which are greater than other groups.The percentage of CD34+ cells induced by BMSC-CM was 1.07% which was greater than other groups.The yields of HPP-CFC from hematopoietic cells induced by FLSC-CM or BMSC-CM were 7.4 /105 cells (P ＜ 0.01) and 5.8 /105 cells (P ＜ 0.05) which were greater than the yields of control group.The yields of CFU-S from hematopoietic cells induced by FLSC-CM or BMSC-CM were 8.5/5 × 105 cells and 6.75/5 × 105 cells which were also greater than the yields of control group (P ＜ 0.001).[Conclusion] Both YS-SCCM,FL-SCCM,and BM-SCCM could promote hematopoietic differentiation of ESE14.1 cells.Hematopoietic differentiation induced by FL-SCCM or BM-SCCM is more effective,which generates hematopoietic progenitor cells with normal function.Application of FL-SCCM generates more primitive hematopoietic progenitor cells than that of BM-SCCM.

Mesenchymal stem cells (MSCs) play an important role in skin wound repair because of their multi-directional differentiation potential, hematopoietic support and promotion of stem cell implantation, immune regulation and self-replication. Exosomes contain proteins and RNAs, which have anti-tumor immunity, angiogenesis promotion and other physiological functions. Different MSCs-derived exosomes have different mechanisms in the skin traumatic action. The author summarizes the research progress of different MSCs-derived exosomes in the field of skin tissue repair through elaborations on the traditional treatment methods for skin damage, the biological properties of exosomes, the mechanism of MSCs-derived exosomes in skin wound repair and in other diseases, providing reference for improving clinical repair.

Exosomes are phospholipid bilayer vesicles secreted by living cells that can carry a variety of signaling molecules, such as RNA, DNA, protein, and lipids. Exosomes play a role in the transmission of signaling molecules between cells, thus regulating many physiological and pathological processes. The methods of extracting exosomes include differential centrifugation, density gradient centrifugation, exclusion chromatography, ultrafiltration, coprecipitation, polymer immune affinity, microfluidic separation technology, etc. Each of these extraction technologies has advantages and disadvantages; however, there is no unified international standard. In addition, the expression of specific proteins and genetic material of exosomes from different cell sources are different; thus, their expression characteristics and functions are also distinctive. Based on this situation, research on exosomes is limited to preclinical studies, and difficulties and challenges still exist in clinical application. This paper summarizes the progress of research in the field of exosomes, to understand the characteristics, modification and application of exosomes from different cell sources, and to summarize their advantages and disadvantages as well as challenges, which can help researchers better understand and master the performance of exosomes. Furthermore, improvement of standard procedures in the extraction and manufacturing of exosomes is important, as it will provide a reference for researchers to carry out exosome-related translational clinical research.