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Polymorphisms in genes involved in folate metabolism as maternal risk factors for Down syndrome in China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第2期9卷 93-99页

作者： Shao-shuai WANG Fu-yuan QIAO Ling FENG juan-juan lv Department of Obstetrics and Gynecology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496). The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.

关键词： Tetrahydrofllate dehydrogenase Ligases Down syndrome Folate

Amiodarone-induced hepatotoxicity-quantitative measurement of iodine density in the liver using dual-energy computed tomography:Three case reports

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World Journal of Clinical Cases 2020年第20期8卷 4958-4965页

作者： Hai-juan lv Hong-Wei Zhao Department of Radiology The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Amiodarone is the drug most commonly used to manage ***-term amiodarone administration causes hepatotoxicity due to iodine accumulation in the ***,we present three cases of amiodarone-induced hepatotoxicity in patients on long-term oral amiodarone therapy who underwent dual-energy computed tomography(DECT).CASE SUMMARY We report the clinical and iodine density in the liver using DECT in three patients with amiodarone-induced *** enzymes were increased in these three patients,and abdominal DECT without contrast medium showed highly increased attenuation in the ***,the iodine concentration in the liver was *** first patient with amiodarone-induced reversible hepatotoxicity,showed a reversible course of liver function and a decrease in CT values after discontinuation of *** second patient on long-term oral amiodarone had increased iodine concentration in the liver and liver damage,the patient eventually developed rapidly progressive pneumonia and died of multiple organ *** third patient,showed an increased iodine concentration in the liver and elevated liver ***,the patient refused radiofrequency ablation for atrial fibrillation and continued oral amiodarone to control atrial fibrillation,and routine liver function tests were required every 3-6 mo in this *** DECT is a potentially noninvasive diagnostic tool for quantifying iodine concentration in the liver and monitoring adverse reactions due to amiodarone.

关键词： Case report Amiodarone Hepatotoxicity Iodine density Computed tomography Dual energy Arrhythmias

Experimental Study on the Viscoelastic Behaviors of Debris Flow Slurry

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Journal of Mountain Science 2012年第4期9卷 501-510页

作者： WANG Yuyi TAN Rongzhi HU Kaiheng CHEN Feiyue YANG Hongjuan ZHANGJinshan lv juan Key Laboratory of Mountain Hazards and Earth Surface Process Dongchuan Debris Flow Observation and Research Station Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Shanghai Representative Office Anton Paar GmbH Shanghai 200040 China

The rheological properties of most liquid in nature are between liquids and solids, including both elastic changes and viscosity changes, that is socalled ＂viscoelastic＂. Dynamic oscillatory test was used to quantitatively study the distinct viscoelastic behaviors of debris flow slurry in the shear stress conditions for the first time in this study. The debris flow slurry samples were from Jiangjiagou Ravine, Yunnan Province, China. The experimental results were found that at the low and middle stages of shearing, when the angular velocity 09〈72.46 s-1, the loss modulus （G was greater than the storage modulus （G3, i.e. G＂〉G＇. At the late stage of shearing, when the angular velocity co-72.46 s-x, the storage modulus was greater than or equal to the loss G = G, tan -〈 1 （where phase-shift modulus, i.e. ＇〉＂ angle 5=G＂,/G3, and the debris flow slurry was in a gel state. Therefore, the progress of this experimental study further reveals the mechanism of hyperconcentrated debris flows with a high velocity on low-gradient ravines.

关键词： Loss modulus (G" Storage modulus (G' Viscoelastic behaviors Gel state

Peptide binding specificities of HLA-B*5701 and B*5801

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Science China(Life Sciences) 2012年第9期55卷 818-825页

作者： ZHANG YaLan MEI Hu WANG Qing XlEJiangAn lv juan PAN XianChao TAN Wen Key Laboratory of Biorheological Science and Technology(Ministry of Education)Chongqing University Chongqing 400044China College of Bioengineering Chongqing UniversityChongqing 400044China

Recently, genome wide association studies showed that there is a strong association between abacavir-induced serious, idio- syncratic, adverse drag reactions （ADRs） and human leukocyte antigen-B＊5701 （HLA-B＊5701）. Studies also found that ab- acavir-induced ADRs were seldom observed in patients carrying the HLA-B＊5801 subtype. HLA-B＊5801 of the same sero- type （B17） as B＊5701 differs by only 4 amino acids from B＇5701. It is believed that because of these sequence differences, HLA-B＊5801 cannot bind the specific peptides which are required for HLA-B＊5701 to stimulate the T cell immune response. Thus, the difference in peptide binding profiles between HLA-B＊5701 and B＊5801 is an important clue for exploring the mechanisms of abacavir-induced ADRs. VHSE （principal component score vector of hydrophobic, steric, and electronic prop- erties）, a set of amino acid structural descriptors, was employed to establish QSAR models of peptide-binding affinities of HLA-B＊5701 and B＊5801. Optimal linear SVM （support vector machine） models with high predictive capabilities were ob- tained for both B＊5701 and B＇5801. The R2 （coefficient of determination）, Q2 （cross-validated R：）, and RpRE2 （R2 of test set） of two optimal models were 0,7530, 0.7037, 0.6153 （B＇5701） and 0.6074, 0.5966, 0.5762 （B＊5801）, respectively. For B＇5701 and B＇5801, the mutations in positions 45 （MET-THR） and 46 （ALA-GLU） have little influence on the selection specificity of the P2 position of the bound peptide. However, the mutation in position 97 （VAL-ARG） greatly influences the selection speci- ficity of the P7 position. HLA-B＊5701 prefers the bulky and positively charged amino acids at the P7 position. In contrast, HLA-B＊5801 prefers the non-polar hydrophobic amino acids at the P7 position while positively charged amino acids are un- favored.

关键词： human leukocyte antigen B*5701 B*5801 SVM P-I concept VHSE

Mitochondrial DNA4977-bp deletion correlated with reactive oxygen species production and manganese superoxide dismutase expression in gastric tumor cells

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Chinese Medical Journal 2009年第4期122卷 431-436页

作者： WANG juan lv You-yong Laboratory of Molecular Oncology Beijing Cancer Hospital andInstitute Peking University School of Oncology Beijing 100142China

Background Mitochondrial DNA 4977-bp deletion （△mtDNA^4977） was reported in many human neoplasia. However, its biological significance remains to be evaluated and the molecular mechanism needs to be investigated. In this study, we analyzed the frequency of △mtDNA^4977 in gastric cancer （GC） cell lines and tissues, as well as reactive oxygen species （ROS） contents and manganese superoxide dismutase （MnSOD） expression levels in GC cell lines to explore its biological significance and molecular mechanism. Methods Semi-quantitative PCR and real-time PCR were used to detect the incidence of △mtDNA^4977 in 13 GC cell lines and 272 human gastric tissues （108 GC specimens and the respective adjacent normal tissues, and 56 normal gastric mucosa from non-cancer patients）. We further identified intracellular ROS production by flow cytometry and MnSOD expression by semi-quantitative reverse transcription-PCR （RT-PCR） and Western blotting. Statistical analyses were carried out using the Logistic regression analysis and Kaplan-Meier method. Results Based on our earlier study, we optimized the PCR amplification condition by reducing the cycle number. In this study, we systematically documented the high incidence of △mtDNA^4977 in GC cell lines （10/13, 76.9%）, GC tissues （86/108, 79.6%）, matched normal tissues （73/108, 67.6%）, and normal gastric mucosa of non-cancer patients （29/56, 51.8%）. A significantly higher incidence of mutated △mtDNA^4977 was observed in GC tissues with respect to the adjacent normal tissues （79.6% vs 67.6%, P=-0.045）, and they were both higher than that in normal controls （P 〈0.05）. Most importantly, we linked the △mtDNA^4977 mutations with the expression level of MnSOD and ROS contents. The cell lines containing lower expression level of MnSOD was found to have generally higher frequent △mtDNA^4977 and more ROS. Conclusion The decreased anti-oxidative ability, which leads to increased ROS contents, is correlated with the mtDNA damage during gastric c

关键词： DNA, mitochondrial manganese superoxide dismutase reactive oxygen species stomach neoplasms

Fabrication of combustion pyrotechnics for laser and electromagnetic interference shielding

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Defence Technology（防务技术） 2023年第6期24卷 140-147页

作者： Yuan-yuan Yao Shao-hua Jin Jing Huang Dong-ze Li Bo-lin Xu Xi-juan lv Qing-hai Shu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China School of Physics Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China State-owned Changhong Machinery Factory Guilin541002China

The contradiction between flammability and packing density is the technical bottleneck for combustible smoke ***,polyurethane(PU)foams with flammability and resilience were prepared with polyol and isocyanate as raw materials by chemical foaming method,then compounded with metal powders,polytetrafluoroethylene(PTFE),phthalic annychide(PA),*** a certain proportion and pressed into pyrotechnic grain to obtain eco-friendly combustion aerosols with compact density of about1.15 g/cm^(3).The resulting combustion smoke agent combined the advantages of PU foam and pyrotechnic with easy ignition,large smoke production,long duration and low environmental *** transmittance of aerosols for 532 nm and 1064 nm lasers was close to 0,and the EMI SE reached up to65 d B and 35 d B in GPS band and X band,*** addition,the resulting pyrotechnic grains exhibited good mechanical strength and elasticity for sample 1:25,with a compressive strength of22 MPa and an elastic modulus of 195 *** resulting combustion smoke agent is expected to play a potential role in the field of electromagnetic damage and protection.

关键词： Smoke agent Flammability PU foam Laser masking EMI shielding

Laser-driven relativistic electron dynamics in a cylindrical plasma channel

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Chinese Physics B 2018年第3期27卷 314-320页

作者： Pan-Fei Geng Wen-juan lv Xiao-Liang Li Rong-An Tang Ju-Kui Xue Key Laboratory of Atomic ＆ Molecular Physics and Functional Materials of Gansu Province College of Physics and Electronics Engineering. Northwest Normal University Lanzhou 730070. China

The energy and trajectory of the electron, which is irradiated by a high-power laser pulse in a cylindrical plasma channel with a uniform positive charge and a uniform negative current, have been analyzed in terms of a single-electron model of direct laser acceleration. We find that the energy and trajectory of the electron strongly depend on the positive charge density, the negative current density, and the intensity of the laser pulse. The electron can be accelerated significantly only when the positive charge density, the negative current density, and the intensity of the laser pulse are in suitable ranges due to the dephasing rate between the wave and electron motion. Particularly, when their values satisfy a critical condition. the electron can stay in phase with the laser and gain the largest energy from the laser. With the enhancement of the electron energy, strong modulations of the relativistic factor cause a considerable enhancement of the electron transverse oscillations across the channel, which makes the electron trajectory become essentially three-dimensional, even if it is flat at the early stage of the acceleration.

关键词： laser-plasma interaction direct laser acceleration cylindrical plasma channel

Modification of polycarbonateurethane surface with poly （ethylene glycol） monoacrylate and phosphorylcholine glyceraldehyde for anti-platelet adhesion

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 188-196页

作者： Jing YANG juan lv Bin GAO Li ZHANG Dazhi YANG Changcan SHI Jintang GUO Wenzhong LI Yakai FENG School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Tianjin University-Helmholtz-Zentrum Geesthacht Joint Laboratory for Biomaterials and Regenerative Medicine Tianjin 300072 China Key Laboratory of Systems Bioengineering Ministry of Education Tianjin University Tianjin 300072 China University of Rostock Department of Cardiac Surgery Reference & Translation Center for Cardiac Stem Cell Therapy Schillingallee 69 D-18057 Rostock Germany

Poly（ethylene glycol） monoacrylate （PEGMA） is grafted onto polycarbonateurethane （PCU） surface via ultraviolet initiated photopolymerization. The hydroxyl groups of poly（PEGMA） on the surface react with one NCO group of isophorone diisocyanate （IPD1） and another NCO group of IPDI is then hydrolyzed to form amino terminal group, which is further grafted with phosphorylcholine glyceraldehyde to establish a biocompatible hydrophilic structure on the surface. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the successful grafting of both PEG and phosphorylcholine functional groups on the surface. The decrease of the water contact angle for the modified film is caused by synergic effect of PEG and phosphorylcholine, which both have the high hydrophilicity. Furthermore, the number of platelets adhered is relative low on the synergetically modified PCU film compared with the PCU film modified only by poly（PEGMA）. Our synergic modification method using both PEG and phosphorylcho- line may be applied in surface modification of bloodcontacting biomaterials and some relevant devices.

关键词： poly(ethylene glycol) monoacrylate phos-phorylcholine polycarbonateurethane surface modifica-tion anti-platelet adhesion biomaterials

The Method of Teaching Computer English on the Base of Development of Students’ Innovative Ability and Practical Skill

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The Method of Teaching Computer English on the Base of Devel...