BACKGROUND:Bone tissue engineering is the most promising way to treat bone defects at present. The key problem is to construct vascular networks which can provide oxygen and nutrients for new bone, and thereby provide a way for the body metabolism. OBJECTIVE:To review the characteristics of bone tissue engineering scaffold materials and to introduce the development of composite scaffold materials. METHODS:With the key words of“bone tissue engineering, scaffold, vascularization, composite scaffold”in Chinese and in English, respectively, a computer-based search was performed for articles published in CNKI and PubMed databases from January 2001 to January 2014. After the initial screening, the reserved articles were further detailed, summarized and concluded. RESULTS AND CONCLUSION:According to the different sources, the bone tissue engineering scaffold materials can be divided into artificial materials, natural derivatives and composite scaffold materials. Single scaffold is difficult to be the most ideal material for repair of bone defects, while composite scaffold can make up for the defects of the single scaffold to different degrees. Therefore, in recent years, the bone tissue engineering scaffolds have developed from single to composite scaffolds and there is the trend of organic combination of artificial materials and natural derivatives. However, composite scaffolds have many problems to be solved in the clinical application. The main aspect is to control the proportion of the composite scaffold so that the degradation of materials can be matched with growth of tissues and cells. The other one is to keep the porous and high mechanical strength of the composite scaffold.

Objective To investigate the biocompatibility of pure titanium (Ti) and Ti-6Al-7Nb surface treated by sanding acid etch (SLA) on rat osteoblasts. Methods Experiments were divided into four groups, Ti mechanical grinding group (S1 group), Ti sand-blasting acid group (SLA1 group), Ti-6Al-7Nb mechanical grinding group (S2 group) and Ti-6Al-7Nb sand-blasting acid group (SLA2 group). The surface topography of samples was examined by microscope. The contact angle measurement instrument was used to analyse surface hydrophily of SLA1 and SLA2 groups. The surface sediment mor?phology and phase were observed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) in two groups after be?ing soaked into simulated body fluid (SBF) for 7 d,14 d and 21 d. Osteoblasts extracted from rats were seeded on titanium sheets, and the osteoblast cells on different titanium surfaces were observed by inverted microscope. MTT colorimetric meth?od was used to measure the proliferation of osteoblasts. Results Compared with S1 and S2 groups, there were more holes on sample surface of SLA1 and SLA2 groups. The sample surface was hydrophilic structure in SLA1 and SLA2 groups. The con?tact angle was smaller in SLA2 group than that of SLA1 group. The hydroxyapatite coating was firstly observed in SLA2 group at 14 d. The hydroxyapatite coating was found in samples of two groups after 21 d. The proliferative ability of osteo?blasts was stronger in SLA1 and SLA2 groups than that of S1 and S2 groups. And the proliferative ability of osteoblasts was stronger in sample surface of SLA2 group than that of SLA1 group (P<0.05). Conclusion Ti-6Al-7Nb by SLA has good biological compatibility, which is helpful to promote the combination of implant and bone tissue.

Objective To study different e mbolization methods in various aneurys ms with metallic coils. Methods In 6 spherical aneurysms, the e mbolization was p erformed with coils in their bodies, discontinuing the total or part of the bloo d supply to the corresponding viscera. While in 6 diverticulum aneurysms, the em bolization with coils was conducted in their bodies only, maintaining the blood supply of the corresponding viscera. For some pseudoaneurysms, both afferent and efferent arteries were embolized and collateral arterial supplies were prevente d. Results All 19 cases 20 aneurysms, of aneurysms were success fully embolized. Among 8 cases of pseudoaneurysms, bleeding had been stopped in 7 cases. Putting coils in the b odies of aneurysms or embolizing both afferent and efferent arteries improved su ccessful rate. Conclusion Embolizing aneurysms with metallic co ils is an efficient, reliable, and simple interventional method for stopping bleeding.

Objective To investigate immunogenicity and protection efficacy of the recombinant hypoxanthine-guanine-xanthine (HGXPRT) of Plasmodium falciparum expressed in Pichia pastoris. Methods 35 BALB/c mice were divided randomly into five groups: HGXPRT+ISA720 experiment group, HGXPRT+Freund experiment group, ISA720 adjuvant control group, Freund adjuvant control group, and blank control group. BALB/c mice were subcutaneously immunized three times with the HGXPRT protein formulated by either Freund or ISA720 adjuvants at a three weeks interval. Mice were bled via tail vein at 2 weeks after each immunization. Specific antibodies were detected by ELISA as well as IFAT using cultured parasites. The immunized mice were challenged with 105 P.yoelii 10 days after the third immunization and parasitemia was monitored daily by examining Giemsa-stained thin film. Results Strong immune response was induced by the HGXPRT antigen formulated with the adjuvant. Antibody titers of more than 1∶105 were detected after the third immunization while no specific antibody was detected in the mice immunized with adjuvants only. The antibodies against HGXPRT recognized the cultured parasite by IFAT. Four days after mice were challenged with P.yoelii, high parasitemia appeared in the two control groups, which were 24 h earlier than experiment groups. The mean parasitemia of HGXPRT+ISA720 experiment group(29.3%) was significantly lower than that of control groups (70.0%) (P

Objective To analyze the efficiency and specificity of MSP2 alleles genotyping for Plasmodium falci-parum isolates by Nest-PCR and PCR-RFLP. Methods MSP2 alleles from Plasmodium falciparum isolates of Yunnan and Hainan were genotyped by Nest-PCR and PCR-RFLP, respectively, and the efficiency and specificity of the two me-thods were analyzed. Results The conventional Nest-PCR method could detect 79.8% (166/208) alleles of MSP2,and 65.7% (65/99) for 3D7 family, but could not identify the type of any allele. While PCR-RFLP showed 25.3% higher genotyping efficiency than Nest-PCR. Moreover, this method could identify the allele types. Conclusion PCR-RFLP genotyping technique is more efficient and specific than conventional Nest-PCR, and it is a convenient tool in the study on molecular epidemiology of malaria.

Aim To study the insulinotropic effects of Efaroxan and the underlying mechanism in rat βcells. Methods Pancreatic islets were isolated by college-nase p digestion.Radioimmunoassay was used to meas-ure insulin secretion and cAMP level in rat pancreatic islets.Results Efaroxan only potentiated insulin se-cretion at high glucose concentrations(8.3,1 1 .1 mmol ·L -1 )but not at low glucose concentrations.KU1 4R,an antagonist of Efaroxan,remarkably inhibited Efarox-an-potentiated insulin secretion;and similarly,KU1 4R significantly inhibited forskolin-induced and IBMX-in-duced insulin secretion.cAMP measurement showed that forskolin and IBMX significantly increased cAMP levels,but Efaroxan and KU1 4R had no effects on cAMP content in pancreatic islets.Conclusion The mechanism of Efaroxan-potentiated insulin secretion is related to downstream of cAMP signaling pathway, KU1 4R antagonized the downstream of cAMP signaling leading to its inhibitory effects on Efaroxan,forskolin and IBMX-induced insulin secretion.

This article introduces the progress about study of lipid mdeiating action of chitosan. It was found that chitosan could mediate blood lipids and modification of chitosan could improve its lipid mediating activity in animal and human.

The introduction of MOOC to medical education in China can greatly promote the development of modern medical education.Using the content analysis method,the paper systemizes the research literatures on MOOC published in 2013-2015 in China.According to the analysis,currently,the research on MOOC in China is still in the initial stage.Therefore,it proposes the focus of domestic research on MOOC and the research development direction in medical education in the future.

Objective To observe the enhanced inhibitory effect of adenovirus (Ad)-mediated HCCS1 combined with 5-FU on the growth of LoVo cells, and to explore the molecular mechanisms.Methods RT-PCR and Western blot were used to detect the expression of HCCS1 in LoVo cells infected with Ad HCCS1. CCK-8 assay was applied to observe different inhibitory effects of different treatments on growth of LoVo cells. The apoptotic rates were detected by using flow cytometry. The apoptotic proteins were detected by using Western blot. Results ① The recombinant adenovirus, Ad HCCS1, could trigger the expression of HCCS1 in LoVo cell. ② In comparison with controls (92.23%±3.77%), the cell viability rate of LoVo was only (11.23±4.61 )% on 96 h after the combination treatment of 5-FU and Ad-HCCS1 (P<0. 01). ③ The apoptotic rate was (27.57±1.78)% on 72 h after the combination treatment, which was higher than that in 5-FU treated cells (8.64±0.94)%, Ad-HCCS1 treated cells (13.19±1.32)% and 5-FU Ad treated cells (12.16±1.28)%, (P<0. 01). ④ Cathepsin D was only detected in Ad HCCS1-infected cells. When treated with 5-FU, the procaspase-8 was decreased and the cleaved Bid was increased in cytosol. The lowest level of Bax and the highest level of cytoso C and cleaved caspase-3 were detected in cytosols of 5-FU+Ad HCCS1 treated cells. Conclusion The inhibitory and proapoptotic effects are significantly enhanced in LoVo cells when treated with Ad-HCCS1+5-FU. The key protein of the cross-talk is Bax and these data provided a new strategy to treat colorectal carcinomas.