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Dihydroxyflavonol reduces post-infarction left ventricular remodeling by preventing myocyte apoptosis in the non-infarcted zone in goats

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Chinese Medical Journal 2009年第1期122卷 61-67页

作者： WANG Sheng FEI Ke xu ya-wei WANG Liang-xu Chen yan-qin Department of Cardiothoracic SurgeryShanghai 10th People's Hospital Tongji University Shanghai 200072 China Department of Cardiology Shanghai 10th People's Hospital Tongji University Shanghai 200072 China

Background Myocyte apoptosis is considered to be the major causative factor of left ventricular （LV） remodeling following myocardial infarction （MI）. We previously reported that 3＇, 4＇-dihydroxyflavonol （DiOHF）, was able to suppress oxidative stress and preserve the expression of endothelial nitric oxide synthase during myocardial reperfusion injury, which may benefit the reduction of myocyte apoptosis. We therefore aimed to evaluate the potential actions of DiOHF against myocyte apoptosis and post-infarction LV remodeling in this study.Methods Following experimental MI, surgical instrumented goats were randomly assigned into vehicle and DiOHF （2 mg/kg; i.v., daily） groups to receive 4 weeks of reperfusion with corresponding treatments. LV pressure recordings and echocardiogram were performed at baseline, 2 and 4 weeks of reperfusion. Myocardial tissues were collected in the end to determine infarct size and apoptosis related assays.Results LV end-diastolic volume and diameter were significantly increased 4 weeks after MI in the vehicle group, accompanied by reduced posterior wall thickness, septal thickness and LV mass, whereas those changes were markedly prevented by DiOHF treatment. Similarly, significantly reduced infarct size was found in DiOHF group as compared to vehicle group, and DiOHF dramatically inhibited the increase in LV end-diastolic pressure and the reductions in ejection fraction, fraction shortening and dP/dtrnax. Moreover, DiOHF treatment significantly reduced the extent of myocyte apoptosis detected by TUNEL assay, enhanced the protein expression of caspase-3, Fas, Bax and cytochrome c in the non-infarcted myocardium in comparison to vehicle. Conclusions Daily DiOHF treatment during the reperfusion period after MI in the ovine hearts markedly reduced the magnitude of post-infarction LV remodeling through the inhibition of myocyte apoptosis in the remote non-infarcted myocardium.

关键词： flavonoids apoptosis myocardial infarction remodeling heart failure

Feasibility of using 6F angiographic catheters for primary percutaneous coronary intervention in patients with acute myocardial infarction

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Chinese Medical Journal 2010年第10期123卷 1345-1346页

作者： CHEN yan-qing HOU Lei wei Yi-dong LI wei-ming xu ya-wei Department of Emergency Tenth People's Hospital Tongji University Shanghai 200072 China Tenth People's Hospital Tongji University Shanghai 200072 China Department of Cardiology

The transradial access has been used for percutaneous coronary intervention （PCI） for more than 10 years. Many studies have confirmed several advantages of a radial route over the traditional transfemoral approach, some of which include a decreased incidence of access site complications, an earlier ambulation after the procedure which helps make patients more comfortable after the procedure.4-SHowever, the radial artery is easier to spasm as it is smaller than the femoral artery. This kind of phenomenon often happens when shifting from angiographic catheters to guiding catheters.

关键词： transradial percutaneous coronary intervention acute myocardial infarction

Renoprotective effect of alprostadil in combination with statins in patients with mild to moderate renal failure undergoing coronary angiography

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Chinese Medical Journal 2013年第18期126卷 3475-3480页

作者： LIU wei-jing ZHANG Bu-chun GUO Rong wei Yi-dong LI wei-ming xu ya-wei Department of Cardiology Shanghai Tenth People's Hospital Tongji University School of Medicine Shanghai 200072 China

Background The role of alprostadil and statins in contrast-induced acute kidney injury （CI-AKI） is controversial. The purpose of this study was to explore the efficacy of combined therapy with alprostadil and statins in protecting renal function and preventing contrast-induced nephropathy （CIN） in patients undergoing coronary angiography. Methods A total of 156 consecutive patients with mild to moderate renal failure who underwent coronary angiography were enrolled in our study, and randomly categorized into two groups. In the statins group, 80 patients were treated with statins before and after coronary angiography. In the alprostadil plus statins group, 76 patients were treated with statins and alprostadil before and after coronary angiography. Serum creatinine （SCr）, serum cystatin （CysC） and neutrophil gelatinase-associated lipocalin （NGAL） were detected after administration of contrast media, and adverse events were evaluated within six months. Results In both groups, the SCr, CysC and NGAL significantly increased after coronary angiography and peaked at 48, 24 and 6 hours, respectively. SCr, CysC and NGAL were significantly lower in the alprostadil plus statins group than in the statins group （P〈0.05）. The incidence of CIN in the alprostadil plus statins group was slightly lower than in the statins group. The incidence of adverse events within six months in the alprostadil plus statins group was significantly lower than in the statins group （P=0.034）. Conclusions Intravenous alprostadil in combination with oral statins is superior to statins alone for protecting renal function in patients with mild to moderate renal dysfunction who undergo coronary angiography, and can reduce the incidence of adverse events seen within six months.

关键词： alprostadil statins renal failure coronary angiography

Numerical investigations on mechanical characteristics and failure mechanism of outwash deposits based on random meso-structures using discrete element method

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Journal of Central South University 2017年第12期24卷 2894-2905页

作者： ZHANG Qiang xu wei-ya LIU Qin-ya SHEN Jun-liang yaN Long Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education(Hohai University) Research Institute of Geotechnical Engineering Hohai University China Institute of Water Resources and Hydropower Research Department of Physics University of Toronto

Outwash deposit is a unique type of geological materials, and its features such as heterogeneity, discontinuity and nonlinearity determine the complexity of mechanical characteristics and failure mechanism. In this work, random meso-structure of outwash deposits was constructed by the technique of computer random simulation based on characteristics of its meso-structure in the statistical sense and some simplifications, and a series of large direct shear tests on numerical samples of outwash deposits with stone contents of 15%, 30%, 45% and 60% were conducted using the discrete element method to further investigate its mechanical characteristics and failure mechanism under external load. The results show that the deformation characteristics and shear strength of outwash deposits are to some extent improved with the increase of stone content, and the shear stress–shear displacement curves of outwash deposits show great differences at the post-peak stage due to the random spatial distribution and content of stones. From the mesoscopic view, normal directions of contacts between "soil" and "stone" particles undergo apparent deflection as the shear displacement continues during the shearing process, accompanying redistribution of the magnitude of contact forces during the shearing process. For outwash deposits, the shear zone formed after shear failure is an irregular stripe due to the movements of stones near the shear zone, and it expands gradually with the increase of stone content. In addition, there is an approximately linear relation between the mean increment of internal friction angle and the stone content lying between 30% and 60%, and a concave nonlinear relation between the mean increment of cohesion and stone content, which are in good agreement with the existing research results.

关键词： outwash deposits random meso-structures discrete element method numerical tests mechanical characteristics failure mechanism

Micromorphological characterization and random reconstruction of 3D particles based on spherical harmonic analysis

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Journal of Central South University 2017年第5期24卷 1197-1206页

作者： SHI Chong SHEN Jun-liang xu wei-ya WANG Ru-bin WANG wei Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Institute of Geotechnical Research Hohai UniversityNanjing 210098China

The microscopic characteristics of skeletal particles in rock and soil media have important effects on macroscopic mechanical properties. A mathematical procedure called spherical harmonic function analysis was here developed to characterize micromorphology of particles and determine the meso effects in a discrete manner. This method has strong mathematical properties with respect to orthogonality and rotating invariance. It was used here to characterize and reconstruct particle micromorphology in three-dimensional space. The applicability and accuracy of the method were assessed through comparison of basic geometric properties such as volume and surface area. The results show that the micromorphological characteristics of reproduced particles become more and more readily distinguishable as the reproduced order number of spherical harmonic function increases, and the error can be brought below 5% when the order number reaches 10. This level of precision is sharp enough to distinguish the characteristics of real particles. Reconstructed particles of the same size but different reconstructed orders were used to form cylindrical samples, and the stress-strain curves of these samples filled with different-order particles which have their mutual morphological features were compared using PFC3D. Results show that the higher the spherical harmonic order of reconstructed particles, the lower the initial compression modulus and the larger the strain at peak intensity. However, peak strength shows only a random relationship to spherical harmonic order. Microstructure reconstruction was here shown to be an efficient means of numerically simulating of multi-scale rock and soil media and studying the mechanical properties of soil samples.

关键词： meso particle three-dimensional micromorphology spherical harmonic function random reconstruction multi-scale

Characteristics and geological significance of the stress state of the lithosphere in the Qinghai-Tibetan Plateau and its neighboring areas

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Science China Earth Sciences 2024年第6期67卷 1836-1855页

作者： Qianwen ZHANG ya xu wei CHU Shupeng LU Key Lab of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The present-day lithospheric stress state of the Qinghai-Tibetan Plateau and neighboring areas is controlled by both the lithosphere itself and the underlying *** other words,the stress is affected by the gravitational potential energy(GPE)difference caused by the change in the density distribution within the lithosphere and the drag force on the base of the lithosphere caused by mantle *** study of the lithospheric stress state plays an important role in further understanding the dynamic background and mechanism for the evolution of the Qinghai-Tibetan *** this study,the Crust1.0 crustal density model combined with the S40RTS mantle shear wave velocity variation model was used to calculate the *** EGM2008gravity field model was used to calculate the drag force from mantle convection at the base of the *** lithospheric and joint stress fields of the two sources were obtained by solving the force balance under the thin sheet *** way,we could comprehensively analyze the characteristics of the stress state within the *** regions were classified according to the GPE stress field,mantle drag force stress field,the relative magnitude of the two stress fields,and correlation between the two stress fields and surface *** lithospheric stress fields of the Tarim Basin and other stable blocks are mainly controlled by the GPE *** lithospheric stress field in the collision zone between the Indian Plate and the QinghaiTibetan Plateau is predominantly controlled by the deep mantle drag *** lithospheric stress field in the interior of the Plateau is controlled by both GPE and mantle *** correlation between the lithospheric stress field and surface deformation at the southeast margin of the Qinghai-Tibetan Plateau is *** is hypothesized that the presence of lower crustal flow with lower effective viscosity leads to crust-mantle decoupling,and the mantle drag force has a weaker influe

关键词： Qinghai-Tibetan Plateau Gravitational potential energy Mantle convection Lithospheric deviatoric stress field GPS strain rate field

Initial experience with circumferential pulmonary vein isolation guided~ by Overlay Ref and CartoMerge in the treatment of paroxysmal atrial fibrillation

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Chinese Medical Journal 2010年第10期123卷 1269-1272页

作者： TANG Kai ZHAO Dong-dong ZHANG Jing-ying CHEN yan-qing xu ya-wei Department of Cardiology Shanghai Tenth People's Hospital Tong Ji University Shanghai 200072 China

Background CartoMerge has been widely used in guiding circumferential pulmonary vein isolation （CPVI） for the treatment of paroxysmal atrial fibrillation （PAF）. However, the procedure of landmarks selection varies among operators according to their experience. Techniques have to be established to standardize this procedure. We propose that Overlay Ref could facilitate this procedure. This paper aimed to report our initial experience with CPVI guided by Overlay Ref and CartoMerge for the treatment of PAF. Methods Fifty-nine patients with PAF were enrolled in this study. Using Overlay Ref technique, a reference image （inverted） was faded into the live fluoroscopic image. Landmarks of CartoMerge were selected from anatomic points of the top of superior pulmonary veins （PVs） and the bottom of inferior PVs guided by Overlay Ref image. Overlay Ref images were also used to guide the ablation procedure combining with CartoMerge. Results All patients were successfully mapped by CartoMerge guided by Overlay Ref. The distance between the mapping points and the CT surfaces was （1.42±0.67） mm for the patients as a whole. This led to a successful rate of 96% for isolation of pulmonary veins. Duration of ablation procedure was （92±17） minutes. And the total duration of procedure was （139±32） minutes. CartoMerge could also be performed just with 3 paries to 4 paries selected landmarks guided by Overlay Ref without a full anatomic model constructed by Carto. Then, the total duration of procedure could be shortened to （115±38） minutes. Conclusions Overlay Ref technique can facilitate the catheter ablation of PAF and can help to standardize the procedure of landmarks selection.

关键词： circumferential pulmonary vein isolation Overlay Ref technique computed tomography three-dimensional electroanatomic mapping atrial fibrillation

Investigation on jointed rock strength based on fractal theory

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Journal of Central South University 2017年第7期24卷 1619-1626页

作者： yaNG Lan-lan xu wei-ya MENG Qing-xiang WANG Ru-bin Research Institute of Geotechnical Engineering Hohai UniversityNanjing 210098China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Department of Civil&Environmental Engineering University of WaterlooWaterloo N2L 3G1Canada

Strength of discontinuities with complex structure is an important topic in rock engineering.A large number of studies have shown that fractal is applicable in the description of this *** fractal interpolation method for the generation of rock joints,numerical experiments of shear tests of the jointed rock mass model were carried out using FLAC^(3D).The test results show that the real rock joints can be simulated by fractal curves obtained by fractal *** fractal dimension is an important factor for the characterization of jointed rock mass;test results show that the fractal dimension of rock joints can be related to the equivalent cohesion strength and shear strength of the rock *** the fractal dimension of the joint surface is less than critical dimension Dc 1.404,the cohesion strength and shear strength of the rock mass increase as the fractal dimension increases;for larger fractal dimensions,all mechanical parameters decrease as the fractal dimension *** surfaces with different degrees of roughness were obtained by the fractal interpolation *** types of failure modes were observed in the tests:climbing slip failure,climbing gnawing fracture,and non-climbing gnawing fracture.

关键词： rock joints fractal dimension shear strength numerical simulation

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv xu Chen Zi-Shuo Wu ya-Hui Li wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR