BACKGROUND: Light-curing composite resins have been applied in the dental repair due to its beautiful color, excellent physical and chemical properties and easy to operation. However, its insufficient mechanical properties tend to cause composite fractures, resulting in undesired clinical efficacy.OBJECTIVE: To investigate the preparation, properties and biomechanical performances of filler-co-augmented photo-curable resin-based oral materials.METHODS: The nano-silica surface-grafted with poly(methyl methacrylate) (PMMA) was obtained by atom transfer radical polymerization. Co-electrospinning was used to prepare the acrylonitrile/PMMA core-shell nanofibers, and a two-dimensional lactic acid-glycolic acid copolymer nanofiber membrane with a lattice structure was obtained using a copper mesh as a receiving device. The multi-scale and multi-dimensional packing was prepared by sol-precipitation method with silane coupling agent as a raw ethyl ester precursor, and further modified using silane coupling agent. The mechanical properties, volumetric shrinkage, toxicity, and degradation properties of the light-curing resin grafted with SiO2-PMMA were compared with those of the light-curing resin combined with trapezoidal polysiloxane materials grafted with methyl methacrylate. RESULTS AND CONCLUSION: (1) Characterization of the composite resin under scanning electron microscope: the filler SiO2-PMMA core-shell nanofibers dispersed well in the light-curing resin matrix, in the presence of monodisperse phenomenon and less aggregation phenomenon. However, the trapezoidal polysiloxane material in the light-curing resin matrix dispersed unevenly, in the presence of reunion phenomenon. (2) The flexural strength, flexural modulus and fracture work of the light-curing resin graftedwith SiO2-PMMA core-shell nanofibers were significantly higher than those of the trapezoidal polysiloxane-based light-curing resin (P < 0.05). (3) The volume shrinkage of the light-curing resin grafted with SiO2-PMMA core-shell nanofibers was lower than that of the trapezoidal polysiloxane-based light-curing resin (P < 0.05). (4) Compared with the trapezoidal polysiloxane-based light-curing resin, the water absorption and cytotoxicity (absorbance value) of the light-curing resin grafted with SiO2-PMMA core-shell nanofibers were significantly higher than those of the trapezoidal polysiloxane-based light-curing resin (P < 0.05), while the solubility of the light-curing resin grafted with SiO2-PMMA core-shell nanofibers was lower (P < 0.05). It is concluded that the prepared light-curing resin grafted with SiO2-PMMA core-shell nanofibers has excellent properties and biomechanical properties.

OBJECTIVE:To study the vasodilatation effects of the alcohol extract from Uighur medicine Ziziphora clinopodioi-des(EEZ)on isolated rat thoracic aorta vessel rings. METHODS:Isolated rat thoracic aorta vessel rings were prepared. There was a group with intact vessel ring endothelium and a group with vessel ring endothelium removed in the test. After preshrinking the ves-sel rings with phenylephrine(PE),EEZ of 100,300,500,700,900 and 1 100 mg/L was added gradually,concentration-vasodila-tation curve was drawn and maximal vasodilatation rate (Emax) and median effective concentration (EC50) were calculated. For the group with vessel ring endothelium removed,after the vessel ring was pretreated with EEZ at EC50 in calcium-free solution or calci-um-free high-potassium solution,CaCl2 of 0.4,0.8,1.2,1.6,2.0 and 2.4 mmol/L was added gradually,and calcium concentra-tion-tension curve was drawn;following the pretreatment of the vessel ring with EEZ at EC50,1 μmol/L PE was added and shrink tension was recorded and vasoconstriction percentages was calculated. RESULTS:EEZ had vasodilatation effect on the vessel ring preshrunk with PE in a concentration and smooth muscle-dependent manner. The group with intact vessel ring endothelium and the group with vessel ring endothelium removed respectively had Emax of (58.18 ± 16.23)% and (73.54 ± 17.21)%,and EEZ EC50 of 773.27 mg/L. For calcium-free high-potassium solution,EEZ could cause the calcium ion-vasoconstriction curve to move to the right obviously;for calcium-free solution,EEZ could inhibit the vasoconstriction caused by PE. CONCLUSIONS:EEZ has vasodi-latation effects by a mechanism which may be related to inhibiting calcium influx and intracytoplasmic calcium release through the inhibition of voltage-dependent calcium channels(VDCCs),and thus interfering intracytoplasmic calcium ion balance.

A catalytic spectrophotometric method for the determination of micro amounts of osmium has been established based on the catalytic action of Os(Ⅳ) on the oxidation fading reaction of chlorophosphonazo-mA with KIO4 in alkaline-medium. The reaction conditions were optimized by orthogonal experimental design. The detection limit for osmium was 2.0 μg/L.Beer＇s law was obeyed in the range from 7.0 to 25.0 μg/L for Os(Ⅳ). The method has been applied to the determination of micro amounts of Os(Ⅳ) in concentrate of noble metals and secondary alloy,both of the relative errors were 0.9%. Recoveries varied from 95.38% to 106.0%.

Objective To evaluate the home-made occluder in the treatment of VSD and its mid-term and long-term results. Methods From Jan. 2004 to May 2007, percutaneous VSD closure therapy under X-ray monitoring was performed in 78 consecutive VSDpatients, including 43 males and 35 females with an average age of (16.5±8.6) years (ranged 3-37 years). TTE, ECG and Holter examinations were performed in 1 week, 3 months, 1 year and 2 years after the procedure. Results Seventy-three home-made occluder devices with a diameter of 5-16 mm (10.3±3.2 mm) were implanted successfully, with a technical successful rate of 93.6% (73/78). The whole course follow-up were carried out in all 73 successful cases (100%). One week after the procedure ITE detected residual shunt in 8 cases, and three months later the residual shunt was observed in 5 cases. Follow-up check at one and two years after the treatment the residual shunt disappeared completely. For the observation of arrhythmia, occasional atrial premature beats or ventricular premature beats occurred in 28 cases (38.4%) within one week after the procedure, and two patients developed grade Ⅲ complete atrioventricular block at the third day after the surgery. The arrhythmia disappeared after medication of prednisone and nutrient drugs for 4-10 days. Bundle branch blocks were observed in 8 cases (10.1%) at one-year and two-year follow-up. Conclusion For the treatment of VSD, the home-made Amplatzer occluder device is reliable and effective, although a close foUow-up is required after the surgery.

Objective To investigate the relaxant effects of ethanol extract fromRhodiola crenulata (Hook.f.et Thoms.) H.Ohba in isolated rat thoracic aorta and its possible mechanisms.MethodsThe thoracic aortas from male Sprague-Dawley rats were isolated and cut into 3- to 4-mm-wide transverse rings, and the tension in endothelium-intact or endothelium-denuded aortic rings was recorded. The relaxant effects of ethanol extract fromRhodiola crenulata in various concentrations (100, 300, 500, 700, 900, and 1 100 mg/L) in aortic rings precontracted with phenylephrine (1 μmol/L) were observed. The effects of pretreatment with soluble guanylyl cyclase inhibitor ODQ (10 μmol/L) on the relaxant effects of ethanol extract fromRhodiola crenulata were observed. The effects of ethanol extract fromRhodiola crenulataon calcium-induced contractions in calcium-free high-potassium medium and phenylephrine-induced contractions in calcium-free medium were also observed.ResultsEthanol extract fromRhodiola crenulatashowed a concentration-dependent relaxation in aortic rings precontracted with phenylephrine. The maximal relaxations of ethanol extract fromRhodiola crenulataln endothelium-intact or endothelium-denuded aortic rings were 57.4% ± 21.81% and 60.51% ± 0.34%, respectively, with a half-maximal effective concentration of 1 062.88 mg/L. The relaxant effects of ethanol extract fromRhodiola crenulatawere not statistically inhibited by pretreatment with ODQ (P>0.05). Contractions of aortic rings resulted from phenylephrine-induced Ca2+ release from intracellular stores in calcium-free medium or high potassium-induced influx of Ca2+ in calcium-free high-potassium medium were significantly inhibited by ethanol extract fromRhodiola crenulata(allP<0.05).ConclusionEthanol extract fromRhodiola crenulatahas a concentration-dependent vasorelaxation, its mechanisms may be involved in blocking extracellular Ca2+ influx and intracellular Ca2+ release.

Objective To investigate the relationship between the polymorphism of adiponectin -11 ,377C> G gene and the risk of coronary heart disease(CHD). Methods A total of 126 CHD patients and 130 healthy controls were enrolled and the frequency of each genotypes and allele gene of adiponectin -11 ,377C > G were detected by polymerase chain reaction fragment length polymorphism (PCR-RFLP). Results (1) The adiponectin gene -11,377C > G sites existed gene polymorphism and the three genotypes were GG, CG and CC. (2) There was statistical difference between CHD group and control group; The G allele frequency of CHD group was significantly higher than that in control group (P < 0.05); The frequency of the C allele gene in CHD group was significantly decreased (P < 0.05). (3) There was no statistical difference of frequency distribution of each genotype and allele gene of adiponectin -11,377C > G between acute coronary syndrome (ACS) group and stable angina group . ( 4 ) The risk of CHD were increased in CHD patients with G allele gene of adiponectin-11,377C > G (P < 0.05). Conclusions The polymorphism of adiponectin -11,377C > G is associated with the increased risk of CHD. The increased G allele gene frequency may represent the increased risk of CHD.

Objective To study the diagnosis and treatment of primary liver cancer(PLC) with bile duct cancer thrombus (BDT). Methods The clinical data of 21 patients with PLC and BDT admitted in the past 8 years were analyzed retrospectively . Results The major clinical manifestations were the symptoms of primary liver cancer and obstructive jaundice. The correct diagnosis rate was 76.2% before operation. The diagnosis rate of B-us, CT, MRI, ERCP and PTC was 14.3%, 9.52%, 14.3%, 71.4% and 100% respectively. The operative procedures included hepatectomy with removal of BDT ( n =10), hepatectomy combined with extrahepatic bile duct resection ( n =5), thrombectomy through choledochotomy with TACE ( n =3), removal of BDT with HAI ( n =3). The 3,5-year survival rate were 43.20% and 24.60% respectively. Conclusions Multi-examinations should be applied in the diagnosis of PLC with BDT. The comprehensive therapy including surgery and other therapies must be adoptted for PLC with BDT.

Objective To explore the effect of Cx43 protein on improvement of learning and memory ability induced by enriched environment (EE) in rats with traumatic brain injury (TBI). Methods TBI model was made by fluid percussion injury (FPI) in Sprague-Dawley rats. The TBI rats were divided into EE group (A), standard housing (ST) group (B), Cx43 specific antisense oligonucleotides (Cx43 ASODN)+EE group (C) and scrambled sequence ODN+EE group (D) with 6 rats in each group. Another 6 normal rats were taken as the control group. Groups C and D were given hippocampal microinjection of Cx43-ASODN (2 μl/d/rat, 1.5 mmol/L) and ScrbASODN (2 μl/d/ rat, 1.5 mmol/L) respectively. Morris water maze was used to evaluated the learning and memory ability. Results The latency was longer and the traversing times was less in group B than in the control group (P<0.05). The latency was shorter in group A than in group B (P<0.05), and there was no significant difference between group A and the control group (P>0.05) from the 9th day after injury. The traversing times was more in group A than in group B and there was no significant difference between group A and the control group (P>0.05). The latency was longer and the traversing times was less in group C than in group A (P<0.05). Conclusion Cx43 protein may participate in the improvement of the learning and memory ability induced by EE in rats with TBI.

The purpose of this paper is to clarify the structure-activity relationship of anti-tumor activity of diosgenin derivatives in vitro. Study has found that diosgenin can inhibit the reproduction of tumor cells by inducing apoptosis and the main target spot of this effect is Bcl-2. Based on the characteristics of pharmacophoric points' of the three-dimensional pharmacophore for Bcl-2 inhibitors, we have docked lots of diosgenin derivatives with Bcl-2, then synthesized 31 compounds of them, finally assessed the anti-tumor activity of the diosgenin derivatives in vitro against A375, A549, HepG-2 and K562. Preliminary studies of SAR have indicated that the aliphatic esters, and aromatic esters of diosgenin without F ring have no anti-tumor activity in vitro. The triazole bromides of diosgenin all achieve fairly good anti-tumor activity in vitro, and those with larger hydrophobic group have the better activity. The stronger is the hydrogen bonding interaction and dipole-dipole interaction of the heterocyclic of diosgenin and diosgenin without F ring and the acid ester of diosgenin without F ring, the better is the activity of derivatives.

Objective To investigate the effect of methylguanidine and 1-methylhydantoin on cells cytotoxicity, apoptosis in human renal tubular epithelial cell line (HK-2). Methods Human PTEC cell line HK-2 was used in this study. HK-2 was cultured and divided into 3 groups: Norma1 control group (A), methylguanidine group(B) and 1-methylhydantoin group (C). The cell inhibitory rate of HK-2 was detected by MTT method. The cytotoxicity of methylguanidine to HK-2 was determined by NAG release test. Cell apoptosis was evaluated by using Hoechst stain and FACS with Annexin-V/PI. Results The OD value and NAG concentration of creatinine, methylguanidine and 1-methylhydantoin group were compared with normal control group. OD value decreased and NAG concentration significantly increased(0.188±0.011, 0.176±0.010 vs 0.545±0.021, F＝1557.74, P＜0.01; 20.488±0.473, 22.225±0.565 vs 5.125±0.198, F＝3848.22, P＜0.01). By Hoechst stain, pycnosis and apoptotic body could be found when HK-2 was cultivated in methylguanidine 1-methylhydantoin group. In methylguanidine, 1-methylhydantoin group apoptotic HK-2 apparently increased, compared with that in control group (18.23±1.1581, 20.22±1.1433 vs 2.473±0.321, F＝526.06, P＜0.01). Compared with group B, the OD value in group C decreased significantly (0.176±0.010 vs 0.188±0.011,t＝2.26, P＜0.05), NAG concentration increased significantly (22.225±0.565 vs 20.488±0.473,t＝-6.67, P＜0.01), and apoptotic rate in-creased significantly (20.22±1.1433 vs 18.23±1.1581,t＝-2.762, P＜0.05). Conclusions 1-methylhydantoin has more powerful cytotoxic effect to renal tubular epithelial cells than that of Methylguanidine.