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Objective Aiming at the problem of significant anisotropy in the three-dimensional ( 3D) printed polyether-ether-ketone ( PEEK) bone substitutes manufactured by material extrusion technology, taking the femur, the main load-bearing long bone of the lower limb, as an example, the biomechanical properties of the femoral model under different direction in the build chamber were evaluated by the combination of finite element analysis and in-vitro mechanical experiment. Methods A left femoral model was obtained by reconstruction from CT data. The stress and displacement of the 3D printed PEEK femur with different directions in the build chamber under five physiological postures in the human gait cycle were simulated by varying the orthogonal anisotropy mechanical properties. An in-vitro mechanical experiment was conducted to investigate the safety and stability of the femur through a 3D printed PEEK femur. Results When the long axis of the femur model was perpendicular to the building platform of the 3D printer, a better mechanical property was obtained, and the maximum von Mises stress was 46. 56 MPa, which was lower than the yield stress of PEEK, while the maximum displacement was larger than that of the natural femur under same loading condition. Therefore, the 3D printed PEEK femur met the strength requirement, but the stability needs to be improved. Conclusions The long axis is recommended to be perpendicular to the building platform when the material extrusion technology was used for the substitute of the load-bearing long bone, and the effect of its anisotropy on service performance of the substitute should be carefully considered when the 3D printing technology is used for load-bearing bone substitute.

Objective To make finite element analysis and compressive performance test on three-dimensional (3D) printed personalized poly-ether-ether-ketone (PEEK) condyle prosthesis, so as to analyze stress distribution characteristics and mechanical properties of the prosthesis, and to evaluate its clinical value and prospect. Methods The finite element models of PEEK condyle prosthesis, mandible and fixation screw were established by software such as CBCT, Mimics, Geomagic Studio, SolidWorks and ANSYS Workbench. The maximum mastication force was applied, and the maximum stress of the condyle prosthesis and screw, as well as the stress and strain of the mandible were recorded. In order to simulate the actual clinical situation, a special fixture was designed to test compression performance of the condyle prosthesis prepared by the fused deposition modeling (FDM) and selective laser sintering (SLS) at the rate of 1 mm/min. Results The peak stress of the PEEK condyle prosthesis was 10.733 MPa, which was located at the back of the condyle neck. The peak stress of 5 fixing screws was 9.707 5 MPa, which appeared on the 2# and 5# screws near the trailing edge of the mandibular ascending branch. The peak stress of both the prosthesis and the screw was smaller than its yield strength. The maximum pressure of the condyle prosthesis prepared by FDM and SLS was (3 814.7±442.6) N and (1 193.970±260.350) N, respectively. Compared with the SLS preparation, the FDM prepared prosthesis not only had higher compression strength but also better toughness. Conclusions The 3D printed personalized PEEK condyle prosthesis shows uniform stress distributions and good mechanical properties, which can provide the theoretical basis for PEEK as reconstruction material for repairing temporomandibular joint.

OBJECTIVE：To estab lish a method that can comprehensively and rapidly analyze the chemical compositions of Miao medicine Caesalpinia decapetala，and to providing reference for quality control and pharmacodynamic material basis study of C. decapetala . METHODS ：UPLC-Q-TOF-MS/MS was adopted . The determination was performed on Agilent SB-C 18 column with mobile phase consisted of 0.1％ formic acid solution- 0.1％ formic acid acetonitrile （gradient elution ）at the flow rate of 0.25 mL/min. The column temperature was 30 ℃，and sample size was 2 µL. ESI source was applied in negative and positive scanning ion mode and data collection range of m/z 50-1 500. The capillary voltage was 4.5 kV，the atomizing gas （nitrogen）pressure was 1.2 Bar， the solvent removal gas was nitrogen ，the flow rate of solvent removal gas was 8 L/min and the solvent removal gas temperature was 200 ℃. Data Analysis 4.2 software was adopted to analyze fragment ion information of each peak ，and identify chemica l compositions on the basis of relevant literature and mass spectograms of reference substance. RESULTS ：Under positive ion mode ， 9 chemical compounds were identified ；peak 1，2，3，4，5，6，7，8，9 were catechin ，protohematoxylin B ，epicatechin，ethyl gallate，quercetin，luteolin，3-deoxy-hematoxylin chalcone ， isoliquiritigenin and linoleic acid. Under negative ion mode ， U1812403）， totally 21 peaks were confirmed and 13 compounds were identified；peak 3，4，5，6，7，8，9，10，11，12，13，15， 21 were catechins ， brevifolin carboxylic acid ， proto- hematoxylin B ，epicatechin，ethyl gallate ，epicatechin gallate ， quercetin，resveratrol，hematoxylin，luteolin，3-deoxy-hema- toxylin， isoliquiritigenin， linoleic acid. CONCLUSIONS UPLC-Q-TOF-MS/MS method is established successfully for analysis of chemical compositions in C. decapetala .

OBJECTIVE： To study the protective effects of Polygonum orientale extract on myocardial ischemia-reperfusion injury （MIRI） model rats， and to provide reference for it’s deeply development of medicinal source. METHODS： Totally 24 rats were randomly divided into sham operation group （normal saline）， model group （normal saline）， Compound danshen tablet group （positive group， 0.17 g/kg） and P. orientale extract group （86 g/kg， calculated by crude drug）， with 6 rats in each group. All groups were given drugs 2 mL/100 g intragastrically once a day. After 4 d of consecutive administration， MIRI model was induced by the left anterior descending branch of arteria coronaria in all groups except for sham operation group. 24 h after reperfusion， they were given related medicine again. After medication， the changes of electrocardiogram ST segment were monitored in each group. The plasma levels of LDH， CK-MB， CK， cTn-I， SOD and NO were detected in each group. The myocardial infarction rate in each group was calculated and the pathomorphological changes in the myocardium were observed. RESULTS： Compared with sham operation group， ST segment of myocardial electrocardiogram was increased in model group （P＜0.01）. The plasma levels of LDH， CK， CK-MB and cTn-I were increased significantly （P＜0.01）， while the plasma levels of SOD and NO were decreased significantly （P＜0.01）. The rate of myocardial infarction was increased significantly （P＜0.01）， and pathomorphological changes were observed in myocardial tissue such as infiltration of inflammatory cells and loose cytoplasm of cardiac myocytes. Compared with model group， ST segment of myocardial electrocardiogram was decreased significantly in Compound danshen tablet group and P. orientale extract group （P＜0.05）； the plasma levels of LDH， CK， CK-MB and cTn-I were decreased significantly （P＜0.05）， while the plasma levels of SOD and NO were increased significantly （P＜0.05）； the rate of myocardial infarction was decreased significantly （P＜0.05）， and inflammatory cell infiltration and tissue edema in myocardium were relieved to varying degrees. CONCLUSIONS： The protective effect of P. orientale extract protect on MIRI may be exerted by anti-oxidative damage.

OBJECTIVE： To study in vitro metabolism pathway of effective component of Bletilla striata as Militarine in liver microsomes and kinetics characteristics of enzyme-catalyzed reactions. METHODS： The in vitro incubation system of rat and human liver microsomes was established， and incubation reaction of Militarine was performed. UPLC-QTOF-MS was used to identify the structure of its metabolites in combination with UNIFI database and references. Using puerarin as internal standard， UPLC-Triple Quad-MS was used to quantitatively analyze metabolic transformation of Militarine in rat liver microsomes. The kinetic parameters （vmax， km， CLint） of Militarine enzyme-catalyzed reactions with/without reducing coenzyme Ⅱ （NADPH） were calculated by fitting the curves with GraphPad Prism 5.0 software. RESULTS： After incubation in rat and human liver microsomes， Militarine produced a chemical formula C21H29O11， which was presumed to be a metabolite of Militarine ester bond hydrolysis. The kinetic study of enzyme-catalyzed reactions showed that vmax of Militarine enzyme-catalyzed reactions with/without NADPH were 1.955， 2.129 nmol/（h·mg）； km were 8.601， 9.854 nmol/mL； CLint were 0.227 3， 0.216 1 mL/（h·mg）； there was no significant difference between with NADPH and without NADPH. CONCLUSIONS： The main metabolic pathway of Militarine in liver microsomes is the hydrolysis of C1 and C4 ester bonds. Its metabolism does not depend on the pathway of cytochrome P450 enzymes initiated by NADPH.

To improve the preparation speed and quality of moxa cone, a mould for preparation of moxa cone was designed and applied in moxibustion. It consists three parts: a foundation (a flat-bottomed circular cylinder hollow in center), a moxa cone forming tube (a hollow column encircled by two semi-cylinders with symmetrical shape and size, and was inserted in the internal cavity of the foundation); and a compression rod (a solid cylinder used for compressing moxa placed in moxa cone forming tube). The mould is practical, simple, and convenient and can effectively speed up the preparation of moxa cone, and it is safe in application. Moreover, the obtained moxa cones are regular in shape, uniform in dosage and size, dense in texture, and convenient to pack, store and carry.

Objective To investigate the distribution of blaOXA-51-like genes and the clonal relation-ship among Acinetobacter baumannii strains isolated from three teaching hospitals in Guangzhou , China. Methods Fifty-two Acinetobacter baumannii isolates were genotyped by multilocus sequence typing (MLST).eBURST algorithm was performed to define clonal complexes (CCs).blaOXA-51-like genes were am-plified by using polymerase chain reaction ( PCR) and sequenced .Results MLST grouped the A.bauman-nii isolates into 5 existing sequence types (STs) and 7 new STs.STn4 carried allele G1 with a T→C muta-tion at the 3rd nucleotide site (nt3) on the gpi111 locus.STn5 carried allele A1, possessing A→C muta-tions at nt156 and nt159 on the gltA1 locus.ST195 and ST208 accounted for 69.2%of all isolates.Clonal relationship analysis showed that ST 195 and ST208 belonged to CC92.Fifty-one A.baumannii isolates car-ried OXA-66 and the rest one carried OXA-199.Conclusion A.baumannii strains that belonged to CC92 and carried OXA-66 were the predominant genotype circulating in Guangzhou , China.

Objective:To establish a method for the determination of nimesulide granules by HPLC. Methods:An Inertsil ODS-SP C18 column(250 mm × 4. 6 mm,5 μm) was used, and the mobile phase was 0. 01 mol·L-1 potassium hydrogen phosphate anhy-drous-acetonitrile(55∶45)[adjusting pH to (7. 2 ± 0. 05) with phosphoric acid]. The detection wavelength was set at 399nm and the flow rate was 1.0 ml·min-1. The injection volume was 20 μl. Results: The linear range of nimesulide was 0.044-0.222 μg(r=0. 999 9), the average recovery was 99. 22% and RSD was 0. 46%(n=6). Conclusion:The method is simple, accurate with promis-ing sensitivity and reproducibility, and can be used in the determination of nimesulide granules .

In this study, modification technology by surface coating was used to improve the flowability of powder of Chinese herbs extracts. Seven kinds of powder of Chinese herbs extracts were coated with 1% silica nanoparticles using an under-driven Comil. The powder characteristics tester was used to evaluate the flowability of uncoated and coated powders. Surface morphology and particle size distribution of powders were compared by scanning electron microscope (SEM) and optical microscope. The powder hygroscopicity was also investigated. The results showed that, after modification, angle of repose, angle of spatula, compressibility and adhesiveness extremely decreased, and flowability index substantially increased, the powder flowability was significantly improved, especially Gegen and Dahuang extracts powders. Scanning electron microscopy images showed the distribution of silica nanoparticles on the host drug particle surfaces. There were no remarkable changes in the particle size distribution and hygroscopicity of all powders after coating. Therefore, Comilling for surface coating modification technology was an effective method to improve the flowability of Chinese herbs extracts and suggested a possible way forward to enhance the quality of Chinese drugs pharmaceutics in their study and manufacture.
Chemistry, Pharmaceutical ; methods ; Drugs, Chinese Herbal ; chemistry ; Nanoparticles ; chemistry ; Particle Size ; Powders ; chemistry ; Surface Properties