The biocompatibility and mechanical properties of plasma sprayed zirconia coated abutment

PURPOSE@#. The aim of this study was to evaluate the clinical performance and reliability of plasma sprayed nanostructured zirconia (NSZ) coating. @*MATERIALS AND METHODS@#. This study consisted of three areas of analysis: (1) Mechanical property: surface roughness of NSZ coating and bond strength between NSZ coating and titanium specimens were measured, and the microstructure of bonding interface was also observed by scanning election microscope (SEM). (2) Biocompatibility: hemolysis tests, cell proliferation tests, and rat subcutaneous implant test were conducted to evaluate the biocompatibility of NSZ coating. (3) Mechanical compatibility: fracture and artificial aging tests were performed to measure the mechanical compatibility of NSZcoated titanium abutments. @*RESULTS@#. In the mechanical study, 400 μm thick NSZ coatings had the highest bond strength (71.22 ± 1.02 MPa), and a compact transition layer could be observed. In addition, NSZ coating showed excellent biocompatibility in both hemolysis tests and cell proliferation tests. In subcutaneous implant test, NSZcoated plates showed similar inflammation elimination and fibrous tissue formation processes with that of titanium specimens. Regarding fatigue tests, all NSZ-coated abutments survived in the five-year fatigue test and showed sufficient fracture strength (407.65-663.7 N) for incisor teeth. @*CONCLUSION@#. In this study, the plasmasprayed NSZ-coated titanium abutments presented sufficient fracture strength and biocompatibility, and it was demonstrated that plasma spray was a reliable method to prepare high-quality zirconia coating.

Determination of Total Arsenic and Arsenic Species in Blood of Acute Promyelocytic Leukemia Patients Treated with Arsenous Acid / 中国药师

Objective:To quantify the plasma concentrations of inorganic arsenic (As(III) and As(V)) and methylated metabo-lites ( MMA and DMA) , and to detect the total amount of arsenic in blood cells and plasma by high performance liquid chromatogra -phy-hydridegeneration-atomic fluorescence spectrometry ( HPLC-HG-AFS) and HG-AFS methods to clarify the arsenic species in acute promyelocytic leukemia (APL) patients.Methods:The blood cells and plasma were digested by the mixture of HNO 3-H2O2 and ana-lyzed by HG-AFS.For the arsenic species , the plasma samples were prepared with perchloric acid to precipitate protein .The superna-tant was separated on an anion-exchange column in 6 min with isocratic elution using 13 mmol · L-1 CH3 COONa, 3 mmol · L-1 NaH2 PO4 , 4 mmol· L-1 KNO3 and 0.2 mmol· L-1 EDTA-2Na.Results:The methods provided linear range of 0.2-20 ng· ml-1 for total arsenic and 2.0-50 ng· ml-1 for four arsenic species (r>0.9950).The spiked recoveries ranged from 81.2％to 108.6％, and the coefficients of variation for intra-and inter-batch precision were less than 9.3％and 12.5％, respectively.The developed methods were applied successfully in the assay of total arsenic and arsenic species in 5 APL patients.Conclusion:The method is simple, fast and accurate , which can be applied in the assay of arsenic compounds in plasma and blood cells in APL patients .

Comparison of HPLC and CMIA Method in Monitoring Concentration of Phenytoin in Epileptic Patients' Plasma / 医药导报

Objective To establish a high performance liquid chromatography (HPLC) method for determining phenytoin concentration in epilepsy patients' plasma,and compare this method with chemiluminescence microparticle immunoassay (CMIA),and to evaluate the consistency of the two methods.Methods HPLC and CMIA methods were applied to determine the plasma concentration of phenytoin in 60 epileptic patients,respectively.The difference of results was analyzed by two-side paired t-test,and then the correlation and consistency of the two methods were investigated with Passing-Bablok regression and Bland-Altman method.Results There was no significant difference between the results of the two methods (P ＞0.05).The regression equation of the determination results by HPLC (Y) and CMIA (X) was Y=0.992 9X +0.143 7 (R2 =0.992 6,n =60),which indicated the correlation of the two methods was good.Bland-Altman analysis showed that the consistency of the two methods for determining was good.Conclusion HPLC and CMIA method in monitoring plasma concentration of phenytoin have good correlation and consistency.Both methods can be used for therapeutic drug monitoring of phenytoin.

Comparison of RP-HPLC and CMIA Method in the Determination of Valproate in Plasma of Epileptic Pa-tients / 中国药师

Objective:To determine the valproate concentration in plasma of epilepsy patients by HPLC, and compare with the re-sults of chemiluminescence microparticle immunoassay ( CMIA) to evaluate the consistency of the two methods. Methods:HPLC and CMIA was respectively applied to determine the plasma concentration of valproate in 230 epileptic patients. The correlation of the two methods was studied by Passing-Bablok regression and Bland-Altman method. Results:The regression equation of the determination re-sults of HPLC (Y) and CMIA (X) was Y=1. 069 7X+2. 338 2 (R2 =0. 969, n=230), which showed promising correlation. Bland-Altman analysis showed that the consistency of the two methods was poor, and the values of HPLC were higher. Conclusion: HPLC and CMIA used for the determination of valproate plasma concentration show good correlation. However, the consistency is poor and there is system error. In the clinical treatment, adjustment and choice should be paid more attention.

Principle and Application Progress of CRISPR-Cas9 / 昆明医科大学学报

Recently,a fast developing new technology for gene modification named as CRISPR-Cas9 which based on CRISPR-Cas9 system composed of clustered regulatory interspaced short palindromic repeat(CRISPR) and Cas9 nuclease(CRISPR associated system 9,Cas9)has been developed. CRISPR-Cas9 system is a kind of immune mechanism widely found in bacteria and archaea. This mechanism can help bacteria and archaea against exogenous DNA by the approach of specifically breaking DNA. Later,this mechanism was found to be useful for gene modification and gene deletion. At present,this technology has been applied to gene modification and therapy. Many studies have shown that the technology,compared with other genetic technology,has higher efficiency and accuracy,and it has promoted genetic engineering progress. Summarized here is the principle and application advance of CRISPR-Cas9.

Expressions of Toll-like receptors 2 and 4 in skin lesions and peripheral blood from patients with chloasma / 中华皮肤科杂志

Objective To investigate the relationship of Toll-like receptors (TLRs) 2 and 4 with the occurrence of chloasma.Methods Peripheral blood samples were collected from 40 patients with chloasma and 40 healthy human controls,and skin samples were also collected from the lesions of 10 of the patients and normal skin of 10 of the healthy controls.Real time (RT)-PCR was performed to measure the mRNA expressions of TLR2 and TLR4 in skin lesions and blood samples.An immunohistochemical test was conducted to observe the expressions of TLR2 and TLR4 in skin lesions.Statistical analysis was carried out by t test.Results The expressions of TLR2 and TLR4 mRNAs were both significantly higher in skin lesions of the patients than in normal skin of the controls (9.72 ± 2.93 vs.5.10 ± 2.69,t =3.67,P＜ 0.01; 9.52 ± 2.88 vs.4.77 ± 1.90,t =4.36,P＜ 0.01),while no significant difference was found in the mRNA expressions of TLR2 or TLR4 in peripheral blood between the patients and controls (both P ＞ 0.05).As the immunohistochemical test revealed,TLR2 was absent in both the epidermis and vascular endothelial cells in 6 normal control skin samples,weakly expressed in the basal layer of the epidermis but absent in vascular endothelial cells in 4 normal skin samples,and no TLR4 expression was observed in either the epidermis or vascular endothelial cells in these control skin samples.Among the 10 skin samples from chloasma lesions,3 showed TLR2 expression in the whole epidermis,7 in both basal cell layer and prickle cell layer but not in vascular endothelial cells in the superficial dermal layer,all showed strong TLR4 expression in the basal cell layer and weak TLR4 expression in the prickle cell layer,and 3 exhibited TLR4 expression in vascular endothelial cells in the superficial dermal layer.Conclusion TLR-mediated immune responses in local skin might be related to the occurrence of chloasma.

Study on Stability of Liuwei Qiangu Cataplasms / 中国药师

Objective:To investigate the stability of Liuwei Qiangu cataplasms. Methods:The active ingredient( naringin) in the samples was determined by HPLC. Meanwhile, the other indices including character, identification, ointment content, adhesion, mi-crobial limit and so on were detected as well. Results:The results of the accelerated test and long term test showed that Liuwei Qiangu cataplasms were stable. No significant change in each index was found before and after the tests. Conclusion: Liuwei Qiangu cata-plasms are stable at room temperature. The designs of preparation process and package are rational to keep the stability of the prepara-tion.