BACKGROUND: Hyaluronic acid is an important component of extracellular matrix, has good biocompatibility, unique rheological properties and a variety of physiological functions. Therefore, it has wide application prospect in the tissue engineering. OBJECTIVE: To review the latest research progress in hyaluronic acid scaffold materials in different directions of tissue engineering. METHODS: Using the keywords of "hyaluronic acid, tissue engineering, regeneration, scaffold" in English and Chinese, we retrieved relevant articles published from January 2013 to September 2016 in the databases of PubMed, ScienceDirect and CNKI. RESULTS AND CONCLUSION: The application of hyaluronic acid tissue engineering scaffold materials mainly focuses on the regeneration of bone, cartilage, cardiovascular and nerve. The researchers optimize the composition, ratio of different materials, and modification or cross-linking methods to obtain the ideal scaffold materials to match the mechanical properties and physiological activity of the target tissue. However, there are not enough data on the influence of the molecular weight of hyaluronic acid and the original source of other raw materials on the scaffold properties. Further investigations are needed on the clinical transformation of hyaluronic acid tissue engineering products.

Lipopolysaccharides (LPS) contamination in herbal crude polysaccharides is inevitable. The present study was performed to explore the effect of polymyxin B on abolishing the influence of LPS contamination in mononuclear cells. LPS was pretreated with polymyxin B sulfate (PB) at different concentrations for 1, 5 or 24 h, and then used to stimulate RAW264.7 and mouse peritoneal macrophages (MPMs). The nitric oxide (NO) and tumor necrosis factor-α (TNF-α) in cell culture supernatant, as the indications of cell response, were assayed. Bupleurum chinensis polysaccharides (BCPs) with trace amount contamination of LPS was treated with PB. 30 μg·mL of PB, treating LPS (10 and 1 000 ng·mL in stimulating RAW264.7 and MPMs respectively) at 37 °C for 24 h, successfully abolished the stimulating effect of LPS on the cells. When the cells were stimulated with LPS, BCPs further promoted NO production. However, pretreated with PB, BCPs showed a suppression of NO production in MPMs and no change in RAW264.7. In the in vitro experiments, LPS contamination in polysaccharide might bring a great interference in assessing the activity of drug. Pretreatment with PB (30 μg·mL) at 37 °C for 24 h was sufficient to abolish the effects of LPS contamination (10 and 1 000 ng·mL).
Animals ; Bupleurum ; chemistry ; Drug Contamination ; Drugs, Chinese Herbal ; analysis ; pharmacology ; Lipopolysaccharides ; analysis ; antagonists & inhibitors ; Macrophages ; drug effects ; metabolism ; Mice ; Nitric Oxide ; metabolism ; Polymyxin B ; analysis ; pharmacology ; Polysaccharides ; analysis ; pharmacology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the in vitro effects of different culture systems on hematopoietic differentiation ability of induced pluripotent stem (iPS) cells.

METHODTwo culture systems including E8 and mTESR(freeder-free medium), and the classical ES culture medium were chosen for culture of iPS cells. The iPS cells maintaining in above mentioning culcure systems were co-cultured with OP9 cells(murine bone marrow stromal cells) in vitro to be induced to differentiate into hematopoietic stem/progenitor cells. Flow cytometry and real-time quantitative PCR were used to detect the expression of specific hematopoietic markers and the effects of different culture systems on the differentiation of iPS in vitro.

RESULTiPS cultured in the 3 selected medium could be differentiated into hematopoietic stem cells. Efficiency of hematopoietic differentiation was up to 28.4% in classical ES culture system, which was significantly higher than that in E8 and mTESR system.

CONCLUSIONUnder the co-culture with OP9, iPS can differentiate into hematopoietic stem/progenitor cells, which shows higher efficiency when iPS maintained in the ES medium.

Objeetive To explore the effects of renal artery calcification on the progression of diabetic nephropathy (DN),the activation and its role of bone morphogenetic protein 2(BMP2) signal pathway in renal artery of rats.Methods Sixty male SD rats were randomly divided into control group(CON group),DN group and DN with vascular calcification group (DN+VDN group).Rats of group DN and DN + VDN were fed with high sugar and fat diet and injected with streptozocin (STZ) into abdominal cavity to induce diabetes.After diabetic models were successfully made,rats of group DN+ VDN were treated by vitamin D3 plus nicotine.The rats were sacrificed at 8th,12th and 16th week respectively and the levels of renal function,blood glucose and 24 h urinary protein (24-h Upro) were measured.The pathologic changes to the renal artery were observed by yon-Kossa staining and the calcium content was detected by calcium assay kit.The pathologic changes to the kidney were observed by HE.Immunohistochemistry was applied to detect the protein expression of BMP2/Smad1/Runx2/ Osterix signal pathway in the renal artery and real-time PCR were applied to detect the mRNA expression levels of BMP2 and Runx2.Results The calcium content and the deposition of black granules in DN group were significantly higher than those in group CON and lower than DN + VDN group at each time point (P ＜ 0.05).The renal function indices in group DN and group DN+VDN were gradually increased in 8th,12th and 16th weeks,and were higher than those in group CON (P ＜ 0.05).Compared with that in DN group,although the level of BUN,Scr,Cys C and 24-h Upro in DN+VDN group rats were higher at different time point,the level of Cys C at each time point and the level of 24-h Upro in the 16th week showed significant differences (P ＜ 0.05).The pathological damages of the kidney in group DN and DN+VDN showed a continual worsening trend and the pathological changes of the kidney in group DN+VDN were more serious than those in group DN.Furthermore,the levels of BMP2/Smad1/Runx2/Osterix signal protein and BMP2,Runx2 mRNA in DN rats were higher than those in CON group,lower than DN+VDN group at each time point (P ＜ 0.05).Correlation analysis demonstrated that calcium content was positively correlated with serum BUN,Scr,Cys C,24-h Upro and the expression of BMP2,Runx2 mRNA (r=0.835,0.705,0.829,0.897,0.641,0.683,P ＜ 0.01,respectively).Conclusion Renal artery calcification may participate in and promote the progression of DN,and the BMP2 signal pathway may be an important regulating factor in DN with renal artery calcification.

OBJECTIVETo explore the expression of insulin-like growth factor binding protein 3 (IGFBP3) in acute myeloid leukemia and its clinical significance.

METHODSUsing GAPDH as internal reference, IGFBP3 gene expression was detected in the bone marrow mononuclear cells of 43 de novo AML patients, 36 patients with complete remission (CR) and 28 cases of controls by using SYBR-Green I real-time quantitative PCR, the differences of gene expression between the three groups were compared.

RESULTSIGFBP3 gene expression level in the de novo group were lower than that in CR group and control group (P < 0.05), but there was no statistically significant difference of IGFBP3 expression level in CR group and control group (P > 0.05).

CONCLUSIONSThe IGFBP3 as a tumor suppressor gene may play a role in the pathogenesis of acute myeloid leukemia, its expression level is recovered after complete remission, therefore, IGFBP3 can be used as an indicator of evaluating clinical curative effect.

Bone Marrow Cells ; Gene Expression ; Humans ; Insulin-Like Growth Factor Binding Protein 3 ; Leukemia, Myeloid, Acute ; Real-Time Polymerase Chain Reaction