55 research outputs found
Is there an association between mild cognitive impairment and dietary pattern in chinese elderly? Results from a cross-sectional population study
<p>Abstract</p> <p>Background</p> <p>Diet has an impact on cognitive function in most prior studies but its association with Mild Cognitive Impairment (MCI) in Chinese nonagenarians and centenarians has not been explored.</p> <p>Methods</p> <p>870 elder dujiangyan residents aged 90 years or more in 2005 census were investigated at community halls or at home. They underwent the Mini-Mental State Examination (MMSE) for assessment of cognitive function and replied to our questionnaire comprised of 12 food items and other risk factors. MCI was defined by two steps: first, subjects with post-stroke disease, Alzheimer's disease or Parkinson's disease and MMSE< 18 were excluded; and then subjects were categorized as MCI (MMSE scores between 19 and 24) and normal (MMSE scores between 25 and 30). Logistic regression models were used to analyze the association between diet and the prevalence of MCI. The model was adjusted for gender, ages, systolic blood pressure, diastolic blood pressure, body mass index, fasting plasma glucose, total cholesterol, triglycerides, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol, smoking habits, alcohol and tea consumption, educational levels and exercise in baseline dietary assessment.</p> <p>Results</p> <p>364 elderly finally included, 108 (38.71%) men and 171 (61.29%) women of whom were classified as MCI. A significant correlation between MCI and normal in legume was observed (OR, 0.84; 95%CI, 0.72-0.97), and also in animal oil (any oil that obtained from animal substances) (OR, 0.93; 95%CI, 0.88-0.98). There was no statistical difference of other food items between normal and MCI.</p> <p>Conclusions</p> <p>Among Chinese nonagenarians and centenarians, we found there were significant associations between inadequate intake of legume and animal oil and the prevalence of MCI. No significant correlation between other food items and the prevalence of MCI were demonstrated in this study.</p
Supramolecular Assembly and Stimuli-Responsive Behavior of Multielement Hybrid Copolymers
Toward the organic polymer, hybrid elements can be defined as those beyond C, H, O, and N. Polymers comprising hybrid elements, such as Si, P, B, or metal ions have attracted great attention in the design of high performance or smart materials. Introduction of hybrid elements into a polymeric network may also lead to the formation of new intermolecular interactions, thus promote the self-organization of polymer chains to form controllable structures and morphologies. In this chapter, we introduce some of the recent important development in the design and self-assembly of hybrid amphiphilic copolymers. Specific attention was paid on the hybrid amphiphilic copolymers containing POSS, boronic acid, or boronate functional moieties. We introduce the design, synthesis, self-assembly behavior, and properties of these hybrid amphiphilic copolymers in detail. Also, the advantages and drawbacks of these polymers and their corresponding nanoassemblies are discussed
A high performance flexible recyclable supercapacitor with polyaniline by casting in unconventional proportion
Abstract(#br)A new type of recyclable flexible solid-state supercapacitor with good electrochemical performance and folder ability is produced through a facile method. Polyvinylidene fluoride - acetylene black - polyethylene glycol - polyaniline (PVDF-AB-PEG-PANI) film electrode with excellent processability and tailorability is prepared by casting strategy, which uses large amount of PVDF as film former. The new electrode has good performance with excellent flexibility (d r < 1 mm and capacity retention 97.4 % after folding 1000 times) and electrochemical performance (It can utilize the active substance efficiently that it closes to the theoretical value, with high areal capacitance of 890.44 mF cm −2 and volumetric capacitance of 89.04 F cm −3 ). A capacitance retention of 72.5 % is obtained for the supercapacitor based on this electrode after 5000 charging/discharging cycles, even polyaniline is synthesized by conventional method. The most interesting thing is that, the supercapacitor based on this electrode can easily be recycled and reused (capacity retention 97.1 % after 4 recycle times)
Syntheses and characterizations of rare earth compounds RE(HCO2)(3)(HNO2) (H2CO2) (RE = Y, Tb, Dy, Ho, Er, Yb, Tm)
A series of novel inclusion compounds with compositions of RE(HCO2)(3)(HNO2)( H2CO2) (RE = Y, Tb, Dy, Ho, Er, Yb, Tm) were synthesized and structures were characterized by X-ray methods. The orthorhombic structure was shown to be a new type with a non-centrosymmetric space group (20) C222(1) by single crystal structure determinations. It is characterized by networks of rare earth centered square anti-prisms formed by eight oxygen atoms through bridging carbon and nitrogen atoms. The guest formic acid molecules H2CO2 are distributed inside the open tunnels along the crystallographic a axis. The magnetic susceptibility measurements show the heavy rare earth compounds follow the Curie-Weiss law and the calculated numbers of Bohr magnetons are consistent with the RE3+ ions. The yttrium compound shows very weak temperature independent paramagnetism
An airflow-controlled solvent evaporation route to hollow microspheres and colloidosomes
National Natural Science Foundation of China [51173153, U1205113, 51103122]; Scientific and Technical Project of Fujian Province of China [2009J1009]A facile and large-scale method combining airflow-controlled solvent evaporation and amphiphilic copolymer self-assembly has been developed for the generation of hollow polymer microspheres, colloidosomes or even organic-inorganic hybrid colloidosomes. By replacing traditional agitation with the controllable airflow, this surfactant free route showed promising prospect in the fabrication of microcapsules with closed pore morphology. While the hollow polymer microspheres had an adjustable pore structure, the polymer colloidosomes and the hybrid colloidosomes possessed seamless surfaces, making them suitable for the stable encapsulation of small molecules. The hybrid colloidosomes constructed from polymer and Fe3O4 nanoparticles, and the ternary hybrid colloidosomes derived from polymer, polymer nanospheres and Fe3O4 nanoparticles displayed superparamagnetic properties and were excellent contrast agents for magnetic resonance imaging. More importantly, both hybrid colloidosomes and ternary hybrid colloidosomes exhibited a significant evolution of pore morphology from a closed pore structure to an open pore structure in response to the temperature variation, which induced a controllable release of guest molecules
Heterogeneous silver-polyaniline nanocomposites with tunable morphology and controllable catalytic properties
National Natural Science Foundation of China [51173153, U1205113]; Special Program for Key Research of Chinese National Basic Research Program [2011CB612303]; Xiamen Science and Technology Committee [3502Z20121021, 3502Z20120015]This paper introduces not only a simple hydrothermal route to silver-polyaniline (Ag-PANI) nanocomposites with controllable morphology, but also a type of catalyst possessing tunable and switchable catalytic capability. Ag-PANI Janus nanoparticles (NPs) and Ag@PANI core-shell NPs have been constructed successfully at different hydrothermal temperatures. The diameter of both Ag and PANI hemispheres of Janus NPs, as well as the PANI shell thickness of core-shell NPs, was finely tuned via adjustment of the feed ratio. We also gained a deeper insight into the functionalities of PANI components in the catalytic capability of the heterogeneous catalysts, choosing catalytic reductions of nitrobenzene (NB) and 4-nitrophenol (4-NP) as model reactions. Our results showed that the catalytic capability of the nanocomposites was dependent on the PANI morphology and hydrophobicity. The PANI shell coating on Ag NPs can concentrate the lipophilic NB, thus leading to an enhanced catalytic capability of Ag@PANI core-shell NPs. However, this enhanced catalytic capability was not observed for Ag-PANI Janus NPs when catalytically reducing NB. More importantly, the catalytic capability of the core-shell NPs in the reduction of hydrophilic 4-NP is switchable by varying the PANI shell from an undoped to a doped state
Interactions between diperoxovanadate complex and amide ligands in aqueous solution
Multinuclear (H-1, C-13, N-14, and V-51) NMR spectroscopy has been used to study the reactions between the diperoxovanadate complex K-3[OV(O-2)(2)(C2O4)]center dot H2O (abbr. bpV(ox)) and ethylenediamine or diethylamine in aqueous solution. The interaction between bpV(ox) and diethylamine was very weak and no new complex was formed. However, bpV(ox) reacted with ethylenediamine giving a new product in which ethylenediamine attached to the vanadium atom via one nitrogen atom in a monodentate manner. Diffusion ordered spectroscopy (DOSY) measurements and theoretical calculations proved the formation of new product in bpV(ox) and ethylenediamine. The vanadium atoms in both [OV(O-2)(2)(C2O4)](3-) and [OV(O-2)(2)(en)](-) species are six coordinated in solution state. (c) 2006 Published by Elsevier B.V
Inhibition of the endogenous CSE/H2S system contributes to hypoxia and serum deprivation-induced apoptosis in mesenchymal stem cells
Mesenchymal stem cells (MSCs) have great potential for repair following acute myocardial infarction. However, a major challenge to MSC therapy is that transplanted cells undergo apoptosis. Hydrogen sulfide (HS) has recently been proposed as an endogenous mediator of cell apoptosis in various systems. The aim of the present study was to investigate the role of endogenous HS in hypoxia and serum deprivation (hypoxia/SD)-induced apoptosis in MSCs. The present study demonstrated that exposure of MSCs to hypoxia/SD caused a significant decrease in HS generation and resulted in marked cell apoptosis. Furthermore, under basal conditions, MSCs expressed cystathionine γ-lyase (CSE) and synthesized HS, whereas CSE expression and activity was inhibited by hypoxia/SD treatment. Overexpression of CSE not only markedly prevented hypoxia/SD-induced decreases in endogenous HS generation but also protected MSCs from apoptosis, while inhibition of CSE by its potent inhibitors significantly deteriorated the effect of hypoxia/SD in MSCs. These data indicate that the HS generation pathway exists in MSCs and the inhibition of the endogenous CSE/HS system contributes to hypoxia/SD-induced apoptosis in MSCs. Our findings suggest that modulation of the CSE/HS system is a potential therapeutic avenue for promoting the viability of transplanted MSCs
Spectroscopic and theoretical study on the interaction between diperoxovanadate complexes and glycyl-histidine
The interaction between diperoxovanadate complexes (K-3[VO(O-2)(2)(C2O4)]center dot H2O and [VO(O-2)(2)(D2O)](-)/[VO(O-2)(2)(HOD)](-)) and glycyl-histidine (abbr. GlyHis) in solution was studied by 1D NMR including variable-temperature NMR, 2D diffusion ordered spectroscopy (DOSY), HMQC and density functional theory (DFT) calculations. The results indicate that a pair of [VO(O-2)(2)(GlyHis)](-) isomers is formed. The vanadium in the new species is coordinated by either the epsilon-N or delta-N in the imidazole ring. The relative ratio of the isomers was affected by temperature. Theoretical calculation results provide a reasonable explanation on the relative coordination capability of different nitrogen sites. Solvation effect is shown to be important for the reactivity of the interaction system. (C) 2010 Elsevier B.V. All rights reserved.Science Research Foundation of Ministry of Health & United Fujian Provincial Health and Education [WKJ2008-2-36]; National Natural Science Foundation of China [20803020, 20828005
Interaction of pyrrolizine derivatives with bovine serum albumin by fluorescence and UV-Vis spectroscopy
National Natural Science Foundation of China [51103122]; Natural Science Foundation of the Fujian Province for the Youth [2011J05137]; Scientific Research Foundation of Fuzhou University [022386]The interaction between pyrrolizine derivatives (PD) and bovine serum albumin (BSA) under imitated physiological conditions was analyzed by fluorescence and ultraviolet spectra. The experiments were conducted at three different temperatures (302, 306 and 310 K) and the results showed that PD caused the fluorescence quenching of BSA through a combined quenching procedure. The binding constant (K-a), binding-site number (n) between PD and BSA at different temperatures were obtained. According to Forster non-radiation energy transfer theory, the binding distance (r) between BSA and PD was calculated. The corresponding thermodynamic parameters (Delta G, Delta H, and Delta S) were also obtained. The comparison of binding potency of PD and BSA suggested that the substituent on the benzene ring could enhance the binding affinity of PD and BSA. Finally, we investigated the possible sub-domain on BSA where bind PD by displacement experiments. (C) 2012 Elsevier B.V. All rights reserved
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