Comparison and analysis of modeling heart valve bracket based on magnetic resonance imaging / 中国组织工程研究

BACKGROUND:Currently,artificial valves used in heart valve operations include biological valves and mechanical valves.The design and processing of the biological valve bracket determine the shape of the biological valves,which in turn determines their service life. OBJECTIVE:Various lobe and bracket models were created based on the spatial geometric equation.Through a comparison of the deformation and stress distribution of various lobe and bracket models,a more rational bracket model was derived.Subsequently,3D printing technology was utilized to produce a solid model. METHODS:According to the geometric and mathematical models of the heart valve leaf and valve bracket,parabolic and ellipsoidal heart valve bracket models were created.Three-dimensional modeling was used to design the heart valve bracket.Two-way fluid-structure coupling analysis was conducted to analyze the force and deformation of the valve bracket in the blood flow field.An appropriate printing method and materials were selected to achieve 3D printing of the heart valve bracket. RESULTS AND CONCLUSION:The distribution rules of deformation,maximum principal stress,and maximum shear stress of the parabolic bracket and ellipsoidal bracket are the same.The deformation and stress of the ellipsoidal bracket were greater than those of the parabolic bracket.The distribution law of maximum principal stress and maximum shear stress was mainly concentrated in the joint part of the lobe and bracket.The total deformation,maximum principal stress,and maximum shear stress of the bracket decrease with the increase of the bracket diameter.

Trends of foodborne diseases in China: lessons from laboratory-based surveillance since 2011 / 医学前沿

Foodborne disease is one of the most important public health issues worldwide. China faces various and unprecedented challenges in all aspects of the food chain. Data from laboratory-based foodborne disease surveillance systems from 2013 to 2016, as well as different regions and ages, can be found along with differences in the patterns of pathogens detected with diverse characteristics. Vibrio parahaemolyticus has been the leading cause of infectious diarrhea in China, especially among adults in coastal regions. Salmonella has been a serious and widely distributed pathogen responsible for substantial socioeconomic burden. Shigella was mostly identified in Northwest China and the inland province (Henan) with less-developed regions among children under 5 years. Data from foodborne disease outbreak reporting system from 2011 to 2016 showed that poisonous animals and plant factors responsible for most deaths were poisonous mushrooms (54.7%) in remote districts in southwest regions. The biological hazard that caused most cases reported (42.3%) was attributed to V. parahaemolyticus, the leading cause of foodborne outbreaks. In this review, we summarize the recent monitoring approach to foodborne diseases in China and compare the results with those in developed countries.

Surveillance of contamination level and antimicrobial resistance analysis of Salmonella on broiler carcasses after chilling in 4 poultry slaughterhouses of Henan Province / 中华预防医学杂志

Objective@#Tests were carried out for obtaining contamination level and antimicrobial resistance of Salmonella on broiler carcasses after chilling in four poultry slaughterhouses in Henan.@*Methods@#Totally, two hundred sixty nine broiler carcasses after chilling were collected in four slaughterhouses with the daily slaughter amount around 15 000 to 50 000. For qualitative analysis of Salmonella EFSA method was used and for quantitative analysis of Salmonella modified Rappaport-Vassiliadis most probable number (MSRV-MPN) method was used. All of the isolates were subjected to antimicrobial susceptibility testing of 8 antibiotics by minimum inhibitory concentration (MIC).@*Results@#Overall, 48.7% (131/269) of the broiler carcasses after chilling were contaminated by Salmonella, and the average of contamination level is 1.32 most probable number MPN/g. Eight serotypes were detected. The dominant serotype is Salmonella enteritidis (93, 71.0%) followed by Salmonella Indiana (21, 16.0%). Only 2 (1.5%) Salmonella enteritidis strains were sensitive to all the tested antibiotics and the remaining 129 isolates were resistant to at least one kind of eight class antibiotics. Among them, resistant to NAL was the common (104, 79.4%) and 51 (38.9%) Salmonella isolates were multidrug-resistant.@*Conclusion@#The contamination rate and multiple antimicrobial resistant of Salmonella on broiler carcasses after chilling from slaughterhouses was very serious, while the isolates contained various serotypes.

Clinical analysis of 125 cases with Mycoplasma pneumoniae pneumonia in children / 中华实验和临床病毒学杂志

Objective@#To investigate and analyze clinical symptoms, auxiliary examination results, therapeutic methods and the prognosis of the pneumonia caused by Mycoplasma pneumoniae in children.@*Methods@#The clinical data including symptoms, auxiliary examination results, therapeutic methods of 125 children with Mycoplasma pneumoniae pneumonia in our hospital from September 2016 to February 2017 were retrospectively analyzed.@*Results@#Among the 125 children with Mycoplasma pneumoniae pneumonia, the main symptoms were cough (100%) and fever (68%) and some cases accompanied by different extra-pulmonary complications. Varying degrees of changes were found from all the children’s abnormal chest X-ray films.@*Conclusions@#The symptoms of Mycoplasma pneumoniae pneumonia in children were serious, with slight clinical signs and varying degrees of change of the X-ray films. Early standardized application of macrolide antibiotics was beneficial for treatment.

Two new sesquiterpenoids from basidiomycete Tyromyces chioneus / 药学学报

Two new sesquiterpenoids, named as tyromols A and B (1 and 2), were isolated from cultures of basidiomycete Tyromyces chioneus, along with two previously reported 15-hydroxy-6 α, 12-epoxy-7β, 10αH, 11βH-spiroax-4-ene (3) and agripilol C (4). Compounds 1-4 were separated and purified by silica gel, RP-18, Sephadex LH-20 column chromatography. Their structures were elucidated on the basis of extensive spectroscopic analysis including IR, MS, 1D and 2D NMR experiments.

Chemical constituents from tubers of Dioscorea bulbifera / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents in the tubers of Dioscorea bulbifera.</p><p><b>METHOD</b>Compounds were isolated and purified with silica gel, ODS and Sephadex LH-20 column chromatography, their structures were determined by using spectroscopic methods including MS and NMR.</p><p><b>RESULT</b>Fourteen compounds were isolated and identified as stigmasterol (1), mono-arachidin (2), 1,7-bis-(4-hydroxyphenyl)-1E,4E,6E-heptatrien-3-one (3), behenic acid (4), demethyl batatasin IV (5), 2,3'-di-hydroxy-4',5'-dimethoxybibenzyl (6), diosbulbin B (7), diosbulbin D (8), docosyl ferulate (9), 7-bis-(4-hydroxyphenyl) -4E, 6E-heptadien-3-one (10), 5,3,4-trihydroxy-3,7-dimethoxyflavone (11), tristin(12), protocatechuic acid (13), adenosine (14).</p><p><b>CONCLUSION</b>Compounds 24, 6, 9, 10, 12, 14 were isolated from the genus Dioscorea for the first time.</p>

Chemical constituents of basidiomycete Hydnum repandum / 中草药

Objective To study the chemical constituents of the fruiting bodies of Hydnum repandum.Methods Separation and purification were performed on silica gel, Sephadex LH-20 and ODS CC. Their sturctures were established by 2D-NMR (1H-1HCOSY, HMQC, HMBC, and NOESY), MS, HR-MS spectra, and ORD data. Results Eleven compounds were obtained and identified as sarcodonin A ( Ⅰ ),scabronine B (Ⅱ), 3β-hydroxy-5α, 8α-epidioxyergosta-6, 22-dien (Ⅲ), (22E, 24R)-ergosta-7, 22-diene3β, 5α, 6β- triol (Ⅳ), (22E, 24R)-ergosta-7, 22-diene-3β-ol (Ⅴ), benzoic acid (Ⅵ), 4-hydroxylbenzaldehyde (Ⅶ), 4-monopropanoylbenzenediol (Ⅷ), ethyl-β-D-glucopyranoside (Ⅸ), thioacetic anhydride ( Ⅹ ), (2S, 2'R, 3S, 4R)-2-(2-hydroxyoctadecanoylamino) docosane-1, 3, 4-triol (Ⅺ). Conclusion All of the compounds are isolated from this fungus for the first time.

Effects of fraction from Phyllanthus urinaria on thrombosis and coagulation system in animals / 中西医结合学报

OBJECTIVE: To investigate the effects of PUW (a fraction containing 60% corilagin from a Chinese herbal plant Phyllanthus urinaria) on thrombosis and coagulation system. METHODS: Myers's method was used to evaluate the protection of intravenously administered PUW against the male mouse sudden death caused by injection of 75 mg/kg arachidonic acid in the tail vein; Charlton's method was modified to observe antithrombotic effect of PUW in rat electrically stimulated carotid artery thrombosis model; and the model of venous thrombosis was produced to investigate the antithrombotic effect of PUW. Rosette assay was used to observe the effect of PUW on platelet-neutrophil adhesion. The effects of PUW were monitored on euglobulin lysis time (ELT), prothrombin time (PT), kaolin partial thromboplastin time (KPTT), and bleeding time (BT) in rats, according to the methods of Kowalski, HUANG Zheng-Liang, and GU Yue-Fang, et al, respectively. RESULTS: The results showed that PUW administered intravenously significantly decreased the mouse mortality, prolonged the occlusion time of rat carotid arteries, and reduced the wet and dry thrombus weight of the inferior vena cava, respectively. PUW markedly inhibited the binding of activated platelets to neutrophils, obtaining 39.7 mg/L of the medium inhibitory concentration. Intravenously administered PUW significantly shortened ELT, prolonged KPTT while had no influence on PT; PUW increased BT in rat tail tips but the BT caused by PUW was much shorter than that by aspirin or urokinase. CONCLUSION: It is suggested that PUW has the potential of antithrombosis due to its inhibition of platelet-neutrophil adhesion. PUW shows the tendency to bleeding, however, it could not cause serious bleeding side effect as compared with aspirin or urokinase.

One step purification of corilagin and ellagic acid from Phyllanthus urinaria using high-speed countercurrent chromatography.

High-speed countercurrent chromatography (HSCCC) has been successfully applied to the preparative separation of corilagin and ellagic acid in one step from the Chinese medicinal plant Phyllanthus urinaria L. by use of direct and successive injections of a crude methanolic extract. Some aspects concerning the practical use of this technique in the described application are considered.