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 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.

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.

Objective To investigate the characteristics of upper airway collapse in patients with obstructive slcep apnea hypopnea syndrome (OSAHS) when muscle is fully relaxed.Methods Thirty male ASA Ⅱ or Ⅲ patients with OSAHS aged 20-59 yr with body mass index 21-36 kg/m2 and apnea-hypopnea index (AHI) of 28-102times/h were studied.The patients were sedated with iv midazolam 1 mg and sufentanil 5 μg.Nasotracheal intubation was then performed under topical anesthesia with 1％ dicaine.After confirmation of correct position of nasotracheal tube,anesthesia was induced with propofol 0.5 mg/kg and vecuronium 0.08 mg/kg and maintained with target-controlled infusion of propofol and remifentanil.BIS was maintained at 40-60.Fiberopticnasopharyngoscope and pressure transducer were inserted via contralateral nasal cavity and connected with imaging workstation.The site and length of the obstruction were measured and calibrated.Positive pressure was applied to the pharyngeal cavity and gradually increased in increments of 1 cm H2O until 20 cm H2O.The change in cross-section area and critical opening pressure at different planes in pharyngeal cavity were recorded.Results Complete obstruction occurred at the plane of hard palate in one patient (3％).The soft palate and uvula completely collapsed in all 30 patients (100 ％).The collapse occurred at tongue level in 23 patients (77 ％).Every 1 cm H2O increase in pressure produced increase in cross-section area by (10 ± 4)mm2 at the level of hard palate and by(28 ± 18) mm2 at the level of soft palate and uvula.The critical opening pressure ranged from 3 to 18 cm H2O and was≤ 15 cm H2O in 90％ patients.Conclusion Soft palate and uvula collapse in all patients with OSAHS when muscle is fully relaxed.The critical opening pressure is ≤ 15 cm H2O in 90％ patients.

Zinc is essential for cell proliferation and differentiation,especially for the regulation of DNA synthesis and mitosis.On the molecular level,it is a structural constituent of a great number of proteins including enzymes of cellular signaling pathways and transcription factors.Zinc can modulate cellular signal recognition,second messenger metabolism,protein kinase and protein phosphatase activities.It may stimulate or inhibit activities of transcription factors,and it may as well be used as a second messenger involved in cell signaling regulation.

In this study, norcanthridin (NCTD)-encapsulated liposomes were modified with a novel murine anti-human CD19 monoclonal antibody 2E8 (2E8-NCTD-liposomes) and the targeting efficiency and specific cytotoxicity of 2E8-NCTD-liposomes to CD19(+) leukemia cells were evaluated. BALB/c mice were injected with 2E8 hybridoma cells to obtain 2E8 monoclonal antibody (mAb). NCTD-liposomes were prepared by using film dispersion method. 2E8 mAbs were linked to NCTD-liposomes using post-incorporation technology. Flow cytometry showed that the targeting efficiency of purified 2E8 mAbs on CD19(+) Nalm-6 cells was 99.93%. The purified 2E8 mAbs were conjugated with NCTD-liposomes to prepare 2E8-NCTD-liposomes whose targeting efficiency on CD19(+) Nalm-6 was also 95.82%. The average size of 2E8-NCTD-liposomes was 118.32 nm in diameter. HPLC showed that the encapsulation efficiency of NCTD was 46.51%. When the molar ratio of 2E8/Mal-PEG(2000)-DSPE reached 1:50, we obtained the liposomes with 9 2E8 molecules per liposome. The targeting efficiency of 2E8-NCTD-liposomes on CD19(+) leukemia cells was significantly higher than that on CD19-leukemia cells. Similarly, the targeting efficiency of the immunoliposomes was also higher than that of the NCTD-liposomes on CD19(+) leukemia cells. Those results were consistent with those observed by laser scanning confocal microscopy. 3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated that 2E8-NCTD-liposomes specifically killed Nalm-6 cells in a dose- and time-dependent manner. The viability of Nalm-6 cells treated by 2E8-NCTD-liposomes was significantly lower than that of Molt-3 cells and it was also significantly lower than that of Nalm-6 cells treated with the same concentration of NCTD-liposomes or free NCTD. We are led to concluded that 2E8 antigen can serve as a specific targeting molecule of B lineage hematopoietic malignancies for liposome targeting, and 2E8-NCTD-liposomes can be used as a new and effective means for the treatment of B lineage hematopoietic malignancies.