Objective To study the effect of heat treatment with sol-gel method on the surface of Ni-Cr alloy for PFM after Ti coating. Methods To establish the sol-gel method of Ti coating on the surface of Ni-Cr dental casting alloy for PFM(pre-treatment for the surface of Ni-Cr alloy,preparation of sol,coating,heat treatment) and to evaluate the color and fragmentation of 10 materials after heat treatment by ISO 10289. Results When kept at a higher condensation temperature and held for a longer time,the materials had less fragmentation.A higher agglutination temperature and a longer time made the materials look deep.When the condensation process was heat treated at(200 ℃) for 2 h and the agglutination process at 450 ℃ for 2 h,the thin film of Ti combined firmly with the surface of Ni-Cr alloy. Conclusion The procedure for heat treatment of Ti coating will affect the level of oxidation reaction on the surface of Ni-Cr alloy,and will change the level of combination between Ti and Ni-Cr alloy.

Objective To study the effect of Mutans Streptococcus(S.Mutans) on the corrosion resistance of Ni-Cr alloy. Methods S.Mutans were isolated in TSB,and then 10~(5)10~6 CFU/mL of bacterial population was reached.The self-corrosion electrical current density and the corrosion electrical current potential of Ni-Cr alloy were found from polarization curves under the condition with or without media plus S.Mutans.The surface of Ni-Cr alloy after bacterial corrosion was examined with X-ray photoelectron spectroscopy(XPS) to find out different element contents.(Results)From polarization curves,it could be found that the self-corrosion electrical current density and the corrosion electrical current potential of Ni-Cr alloy without S.Mutans were 53.5 ?A/cm~(2)and-62 mV,and those with S.Mutans were 75.7 ?A/cm~(2)and-220 mV.Examination of XPS showed that besides Ni and Cr,the element of chlorine(Cl),sulphur(S),calcium(Ca) could be found on the surface of Ni-Cr alloy after bacterial corrosion.(Conclusion Because of) the metabolism of S.Mutans,an oxide film could be destroyed and a biofilm be formed on the surface of Ni-Cr alloy.Bacterial corrosion could lower the corrosion resistance performance of Ni-Cr alloy.

This article was aimed to study the mechanism of interaction between human serum albumin (HSA) and zinc ions, in order to provide the information on the secondary structure modification of HSA and the thermodynamics parameters using circular dichroism (CD) and isothermal titration calorimetry (ITC). CD and ITC were applied in the study. The concentration of HSA were 0.025 mmol·L-1, 0.05 mmol·L-1, 0.1 mmol·L-1, and 0.2 mmol·L-1, respectively. The concentration of zinc ion was 5 mmol·L-1. The CD analysis revealed that the secondary structure modification of HSA differed depending on the concentration of HAS. And the content ofα-helix was inversely proportional to the concentration of HSA. When the concentration of HSA was 0.2 mmol·L-1, the content ofα-helix was special. A series of thermodynamics parameters including association constants (Kb), stoichiometry (N), entropy (ΔS) and enthalpy (ΔH) were investigated by ITC analysis. And two types of binding sites were observed when ZnSO4(mmol·L-1)?HSA (mmol·L-1)= 5?0.2. The secondary structure modification of HSA interacting with zinc ions depended on the concentration of HSA, a dramatic reduction ofα-helix was detected when the concentration of HSA attained 0.2 mmol·L-1. And the protein hydrophobicity reduction and peptide chains expansion were equally observed at this concentration. The ITC analysis also revealed endothermic and exothermic binding sites in the ZnSO4-HSA interaction when ZnSO4 (mmol·L-1)?HSA (mmol·L-1)= 5?0.2, indicating that the endothermic sites were specific but not preferential for zinc ions interactions. These results provided theoretical supports for the application of Zn2+ to open the endothermic sites of HSA.

BACKGROUND:Manual reduction for external fixation of distal radius fractures can achieve good outcomes.
OBJECTIVE:To carry out the bibliometric analysis on manual reduction for external fixation of distal radius fractures.
METHODS:Literatures concerning reduction for external fixation of distal radius fractures were retrieved in CNKI database from 2003 to 2012. The keywords were“external fixation;distal radius fractures”. Duplicate and irrelevant articles were eliminated, and a total of 408 articles were retrieved. A bibliometric analysis of these 408 articles was performed in terms of publishing time and number, subject categories, source journals, research institutions, times cited and download frequency.
RESULTS AND CONCLUSION:Literatures concerning manual reduction for external fixation of distal radius fractures exhibit an upward trend in number. In 2012, there were 85 relevant articles. In the past 10 years, 18 relevant articles have been published in Chinese Journal of Traditional Medical Traumatology&Orthopedics, which is the most. There are not many relevant studies in various research units, only 1-7 articles published per unit, and five articles are funded.

Adult ; Female ; Hemoptysis ; etiology ; Humans ; Pulmonary Artery ; abnormalities ; Recurrence ; Tomography, X-Ray Computed

The benefit achieved by concurrent chemoradiotherapy (CCR) and sequential chemoradiotherapy (SCR) vs radiotherapy (RT) alone for patients with stage II-IVa nasopharyngeal carcinoma (NPC) was compared. A total of 113 patients with stage II-IV a NPC were allotted into CCR group (n=38), SCR group (n=36) and RT alone group (n=39). All patients were irradiated with the same RT technique to ≥66 Gy at 2 Gy per fraction, conventional 5 fractions/week in all groups. The CCR group received concurrent chemotherapy of weekly cisplatin for 7 weeks, and the SCR group received neoadjuvant and (or) adjuvant chemotherapy. The results showed that the 3- and 5-year overall survival rate was significantly higher in CCR group than in RT alone group (92.16% vs 61.54%, 81.58% vs 51.28%, P<0.005). The median survival time was significantly longer in CCR group than in RT alone group (67.8 months vs 52.7 months, P<0.005). It was concluded that CCR could significantly improve overall survival rate, progression-free survival rate, and median survival time when compared with RT alone.

AIMTo study the cellular uptake of chitosan oligosaccharide nanoparticles by A549 cells and evaluate the possibility of chitosan oligosaccharide nanoparticles used as a potential drug carrier.

METHODSChitosan oligosaccharide (CSO) was obtained by ultrafiltration separation after regulation of the condition of chitosanase degradation. The molecular weight of CSO was determined by gel permeation chromatography (GPC). Chitosan oligosaccharide nanoparticles (CSO-NPs) were prepared by a novel solvent diffusion method in an oil system after the carrier material grafted fluorescein isothiocyanate (FITC) and the particle size distribution and zeta potential were determined by light scattering and electrophoretic mobility. The cytotoxicity and uptake of FITC-labeled CSO-NPs in A549 cells following various incubation periods were studied by the MTT method and fluorescence microscopy, flow cytometric analysis, respectively.

RESULTSThe molecular weight (MW) of CSO was 18,678 u and the particles sizes of CSO-NPs were 133.3 nm (number average) and 368.2 nm (volume average), respectively. The IC50 of CSO and CSO-NPs were 944.36 and 643.16 mg x L(-1), respectively, and the result showed low cytotoxicity. Cellular uptake of CSO and CSO-NPs were relative to the concentration and the incubation time. Internalization of CSO-NPs increased 0.49 - 13.9 times more than that of the CSO with the same incubation time.

CONCLUSIONCSO and CSO-NPs have low cytotoxicity. CSO-NPs can significantly improved the uptake of CSO-NPs by A549 cells compared to the same molecular weight of CSO.

Adenocarcinoma ; pathology ; Chitin ; analogs & derivatives ; metabolism ; toxicity ; Chitosan ; Dose-Response Relationship, Drug ; Drug Carriers ; metabolism ; toxicity ; Epithelial Cells ; drug effects ; metabolism ; Humans ; Lung Neoplasms ; pathology ; Nanotechnology ; Oligosaccharides ; metabolism ; toxicity ; Particle Size ; Time Factors ; Tumor Cells, Cultured

AIMTo investigate the cellular uptake of monostearin solid lipid nanoparticles (MSLN) and the influence on the cellular uptake by MSLN modified with PEG2000 in human-type II cell alveolar epithelial cell line (A549) and murine macrophages cell line (J774A1).

METHODSMSLN were prepared by a novel solvent diffusion method. The particle size distribution and zeta potential of MSLN, measured by light scattering and electrophoretic mobility, were investigated. The cytotoxicity of MSLN and MTX-loaded MSLN in A549 cells were performed by the MTT method. Rhodamine B was incorporated into solid lipid nanoparticles as fluorescent marker, after PEG2000 integrating monostearin during preparation, the cellular uptake of MSLN by A549 and J774A1 cell lines were determined spectrofluorimetrically.

RESULTSThe IC50 of MSLN and MTX-loaded MSLN on A549 cells were 227.56 microg x mL(-1) and 71.37 microg x mL(-1), respectively. The percentage of cellular uptake showed a negative correlation to the concentration of MSLN in incubation medium and the internalization behaved rapidly. Contrary to situation in J774A1 cell line, internalization of solid lipid nanoparticles was promoted with increasing the content of PEG2000 incorporated into MSLN in A549 cell line.

CONCLUSIONAfter modifying MSLN with PEG2000, it represents relative lower phagocytosis by J774A1 cell line and higher uptake in A549 cell line.

Adenocarcinoma ; metabolism ; pathology ; Animals ; Cell Line ; Cell Line, Tumor ; Cell Survival ; drug effects ; Drug Carriers ; Drug Delivery Systems ; Glycerides ; chemistry ; metabolism ; toxicity ; Humans ; Lung Neoplasms ; metabolism ; pathology ; Macrophages ; cytology ; Mice ; Nanotechnology ; Particle Size ; Phagocytosis

AIMTo prepare the micelles of stearic acid-grafted chitosan oligosaccharide and investigate the drug release from micelles.

METHODSMediated by a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), stearic acid (SA) was covalently attached to chitosan oligosaccharide (CSO), and the graft polymer (CSO-SA) was obtained. The critical aggregation concentration (CAC) of the CSO-SA was determined by measuring the fluorescence intensity of pyrene as a fluorescent probe. The effect of various pH dispersed media and concentration of tripolyphosphate sodium (TPP) on the micellar size distribution and zeta-potential measured by light scattering and electrophoretic mobility, was investigated. In buffers of different pH, the release profiles of methotrexate (MTX) from micelles were evaluated.

RESULTSThe CAC value of CSO-SA in deionized water was 0.05 g x L(-1). The mean diameter of CSO-SA micelles was 26.7 nm and the zeta potential was (55.9 +/- 0.1) mV. With the increase of TPP concentration, the size and MTX encapsulation of CSO-SA micelles increased, while the zeta-potential decreased. With the decrease of pH value of dispersed media, the size and zeta-potential of CSO-SA micelles increased, and the MTX encapsulation in CSO-SA micelles decreased. While the enhancement of drug release from the micelles was observed.

CONCLUSIONThe graft polymer of CSO-SA provides polymeric micelles, which possessed a low CAC value in aqueous media. The drug release in vitro from CSO-SA micelles was affected by the pH of delivery media.

Chitosan ; administration & dosage ; chemistry ; Drug Carriers ; Drug Delivery Systems ; Hydrogen-Ion Concentration ; Methotrexate ; administration & dosage ; chemistry ; Micelles ; Oligosaccharides ; administration & dosage ; chemistry ; Particle Size ; Polymers ; Polyphosphates ; Solubility ; Stearic Acids ; administration & dosage ; chemistry

OBJECTIVETo investigate effects of the variation of immune function in high humidity environment in different time, and lay a foundation for further study of the related mechanism.

METHODThirty SD rats were divided into 3 groups (n = 10): 20 day group, 40 day group in 90% relative humidity chamber and control group in normal relative humidity. Peripheral blood and spleens were collected to detect the levels of T lymphocyte subsets by Flow Cytometery.

RESULTSIn peripheral blood of the 20 day group rats, the CD3+ %, CD4+ %, CD8+ % and CD4+/CD8+ were 52.91 +/- 6.27, 37.80 +/- 4.11, 14.85 +/- 3.73 and 2.72 +/- 0.82 separately. Expect CD3+ %, they all had significant differences (P < 0.05). In addition, the data of the 40 day group rats showed no diversity in statistics. In spleen, CD8+ % of the 20 day group rats was 6.23 +/- 2.87 with significant differences (P < 0.05) and IgG, IgA and IgM did not change a lot in blood serum of the high humidity groups except C3 of the 20 days group (P < 0.05).

CONCLUSIONIn high humidity environment, the immune function of the rats increased in the initial stage. As time went on, the immune function gradually went to normal level through the self adjustment.

Acclimatization ; Animals ; Humidity ; Rats ; Rats, Sprague-Dawley ; Spleen ; immunology ; T-Lymphocyte Subsets ; immunology