Publications by authors named "YongMei Wang"

A C(2)-symmetric tetraamine catalyst was developed for the asymmetric Michael addition of ketones to chalcones. The corresponding adducts 1,5-dicarbonyl compounds were obtained in good chemical yields with high levels of diastereo- and enantioselectivities (up to >99 : 1 dr and 93% ee) under mild conditions. By studying the ESI-MS of the intermediates, a proposed mechanism was disclosed.

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This study investigated the antioxidant capacities that included Ferric reducing antioxidant power (FRAP), 1, 1-diphenyl-2-picryl hydrazine (DPPH), ·OH and O(2·)(-)-scavenging abilities, total polyphenols (TP) and total anthocyanins (TA) in pomegranate (Punica granatum L.) juice (PJ) and pomegranate wine (PW). The correlations among them were also analyzed.

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Objective: To explore the anti-neoplastic and anti-metastatic effects of thymoquinone on the model of human pancreatic carcinoma established by surgical orthotopic implantation (SOI) in nude mice.

Methods: After a 3-week implantation, 40 mice were randomized into 4 groups: control group, feed with 1% ethanol; low-dose thymoquinone group (L-TQ 5 mg/kg BW daily by i.g.

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We used multiscale modeling technique and investigated several issues in non-viral based gene delivery using polyethyelenimine (PEI). Atomistic molecular dynamic simulations captured the spontaneous complex formation between a short PEI chain and a poly-(L) lysine (PLL) chain with DNA helices. Atomic structures obtained for DNA/PEI and DNA/PLL complex compared very well with X-ray diffraction data.

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Purpose: Lipoprotein-associated phospholipase A₂ (Lp-PLA₂) is an inflammatory enzyme expressed in atherosclerotic plaques. We investigated the association of circulating Lp-PLA₂ with characteristics of vulnerable coronary atherosclerotic plaques.

Materials And Methods: We recruited 113 patients with either unstable angina (UA, n=59) and stable angina (SA, n=54) by coronary angiography.

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Integrin receptors bind extracellular matrix proteins, and this link between the cell membrane and the surrounding matrix may translate skeletal loading to biologic activity in osteoprogenitor cells. The interaction between integrin and growth factor receptors allows for mechanically induced regulation of growth factor signaling. Skeletal unloading leads to decreased bone formation and osteoblast proliferation that can be explained in part by a failure of insulin-like growth factor 1 (IGF-1) to activate its signaling pathways in unloaded bone.

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This review focuses on the mechanisms by which PTH stimulates both osteoblast and osteoclast function, emphasizing the critical role that IGF-I plays in these processes. After reviewing the current literature on the skeletal actions of PTH and the modulation of IGF action on bone by the different IGF-binding proteins, the review then examines studies from mouse models in which IGF-I or its receptor have been selectively deleted in different cells of the skeletal system, in particular osteoprogenitors, mature osteoblasts, and osteoclasts. Mice in which IGF-I production has been deleted from all cells are deficient in both bone formation and bone resorption with few osteoblasts or osteoclasts in bone in vivo, reduced osteoblast colony forming units, and an inability of either the osteoblasts or osteoclast precursors to support osteoclastogenesis in vitro.

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The abundant fruit hulls of tea-oil tree (Camellia oleifera) are still underutilized and wastefully discaded to pollute the environment. In order to solve this problem and better utilize the fruit hulls of C. oleifera, a microwave-assisted extraction system was used to extract their polyphenols using water as the extraction solvent.

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To determine the value of dual-energy CT (DECT) and combined information of perfusion and angiography in diagnosing coronary artery disease (CAD), with single photon emission computed tomography (SPECT) and quantitative coronary angiography (QCA) as a reference standard. Thirty-four patients were enrolled in this study. DECT was used as a contrast-enhanced retrospectively ECG-gated scan protocol during the rest state and tubes were set at 140/100 kV.

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The atmospheric ultraviolet imaging spectrograph (AUVIS) is an ultraviolet imaging spectrograph that uses a two-dimensional charge-coupled device detector to collect both the spectrum and the swath perpendicular to the flight direction. The design of the system components, the principle, and the main specifications of the AUVIS are introduced. The calibration theory was studied.

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Systemic derangements and perinatal death of generalized insulin-like growth factor 1 (IGF-1) and IGF-1 receptor (IGF-1R) knockout mice preclude definitive assessment of IGF-1R actions in growth-plate (GP) chondrocytes. We generated cartilage-specific Igf1r knockout ((Cart) Igf1r(-/-)) mice to investigate local control of chondrocyte differentiation in the GP by this receptor. These mice died shortly after birth and showed disorganized chondrocyte columns, delayed ossification and vascular invasion, decreased cell proliferation, increased apoptosis, and increased expression of parathyroid hormone-related protein (Pthrp) RNA and protein in their GPs.

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The infructescence of Platycarya strobilacea is a rich source of ellagic acid (EA) which has shown antioxidant, anticancer and antimutagen properties. Response surface methodology (RSM) was used to optimize the conditions for ultrasonic extraction of EA from infructescence of P. strobilacea.

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Polyolefins are the most widely produced synthetic polymer commodity and are found in countless applications ranging from bottles, packaging films to bullet-proof jackets, etc. Such widely different applications rely on high variability in the physical properties of polyolefins, which is a result of variations in microstructure, chemical composition and molar mass. Though polyolefins contain only carbon (C) and hydrogen (H) atoms, the microstructures of polyolefins are extremely variable, differing in the nature of the monomers (e.

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Objective: To investigate the levels of insulin-like growth factor-1(IGF-1), insulin (INS)and growth hormone (GH) in the cord blood of neonates with intrauterine growth retardation (IUGR), and to assess the effects of the endocrine environment on IUGR.

Methods: Sixty-three newborn infants were selected, including 37 males and 26 females. According to birth weight, they were classified into IUGR group (n=33) and control group (normal birth weight, n=30).

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The partitioning of star branched polymers into a slit pore at three different chromatography conditions, namely, size exclusion chromatography (SEC), liquid chromatography at the critical condition (LCCC), and liquid adsorption chromatography (LAC) have been investigated with lattice Monte Carlo simulations. Two different chain models are used: random walks (RW) that have no excluded volume interaction and self-avoiding walks (SAW) that have excluded volume interaction. The simulation data obtained for the two chain models are compared to illustrate the effect of excluded volume interactions on the partitioning of star branched polymers.

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Phenolic compounds are present at very high concentrations in the bark of Acacia mangium. These compounds are known to have strong antioxidant activity and thus different beneficial effects on human health. Phenolic compounds in bark of A.

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Coarse-grained molecular dynamics simulations are used to study the condensation of single polyanion chains with block copolymers composed of cationic and neutral blocks. The simulations are an effort to model complexes formed with DNA and cationic copolymers such as polyethylenimine-g-polyethylene glycol which have been used in gene delivery. The simulations reveal that increases in the cationic block length of the copolymer result in greater condensation of the polyanion.

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In this paper, we present a new blockwise permutation test approach based on the moments of the test statistic. The method is of importance to functional neuroimaging studies. In order to preserve the exchangeability condition required in permutation, we divide the time series into certain exchangeability blocks.

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In this paper, we propose a model based clustering method for functional magnetic resonance imaging (fMRI) data to detect the functional connectivity network. The Potts model, which represents spatial interactions of neighboring voxels, is introduced to integrate the temporal mixture regression modeling into one single unified model. The estimation of the parameters is achieved through a restoration maximization (RM) algorithm for computation efficiency and accuracy.

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The success of polyethyleneimine (PEI) as a nonviral-based gene delivery vector has been attributed to its proton buffering capacity. Despite the great interest in PEI for its use in nonviral-based gene delivery, the protonation behavior of PEI in solution is not well understood. Earlier experimental studies have reported inconsistent values of the protonation state of PEI.

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Luminescent bifunctional core-shell nanoparticles were successfully constructed from block copolymer encapsulating Re(phen) complexes for simultaneous cell imaging and gene transfection in living cells.

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Complexes formed from DNA and polycations are of interest because of their potential use in gene therapy; however, there remains a lack of understanding of the structure and formation of DNA-polycation complexes at atomic scale. In this work, molecular dynamics simulations of the DNA duplex d(CGCGAATTCGCG) in the presence of polycation chains are carried out to shed light on the specific atomic interaction that result in complex formation. The structures of complexes formed from DNA with polyethylenimine, which is considered one of the most promising DNA vector candidates, and a second polycation, poly-L-lysine, are compared.

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The Anisotropic Network Model (ANM) is used to study motions of the 30S small ribosomal subunit. The effect of the absence of certain subunits on the motions of the remaining partial structures was investigated by removing one protein, pairs of proteins and selected sets of proteins at a time. Our results show that the removal of some proteins doesn't change the large-scale dynamics of the partial structures, but the removal of certain subunits does cause significant changes in motion of the remaining structure, and these changes can be reverted by the removal of other subunits, which indicates interdependence between motions of various parts of the 30S ribosomal structure.

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We report a rare case of a quinticuspid aortic valve associated with regurgitation and dilation of the ascending aorta, which was diagnosed and post-surgically followed up by cardiovascular magnetic resonance and dual source computed tomography.

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It is possible to obtain some space weather parameters such as the electron flux and mean energy of the precipitating electrons from the far ultraviolet (FUV) radiance of the aurora observed in a nadir viewing geometry, and the FUV image intensifier is one of the key equipment that used for observation the FUV radiance of the aurora in a nadir viewing geometry. The capability of this equipment will affect the whole purpose of the detection. And the responsibility to the wavelength is the most important parameter of image intensifier.

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