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J Xiao et al.
Nanoscale, 5(3), 899-903 (2012-12-22)
Ultrafine tungsten nanocrystals (average size of 3 nm) with a metastable phase (beta-tungsten with A15 structure, β-W) have been prepared by laser ablation of tungsten in liquid nitrogen. The as-prepared metastable nanocrystals exhibited super-stablity, and can keep the same metastable
D Cereceda et al.
Journal of physics. Condensed matter : an Institute of Physics journal, 25(8), 085702-085702 (2013-02-02)
Screw dislocations in bcc metals display non-planar cores at zero temperature which result in high lattice friction and thermally-activated strain rate behavior. In bcc W, electronic structure molecular statics calculations reveal a compact, non-degenerate core with an associated Peierls stress
Katrin Schröder et al.
Free radical biology & medicine, 41(9), 1353-1360 (2006-10-07)
Hyperlipidemia enhances xanthine oxidase (XO) activity. XO is an important source of reactive oxygen species (ROS). Since ROS are thought to promote atherosclerosis, we hypothesized that XO is involved in the development of atherosclerosis. ApoE(-/-) mice were fed a Western-type
Valerio Leoni et al.
Clinical chemistry and laboratory medicine, 42(2), 186-191 (2004-04-06)
24S-Hydroxycholesterol (24OHC) and 27-hydroxycholesterol (27OHC) are two structurally similar oxysterols of different origins--the former almost exclusively formed in the brain and the latter formed to a lesser extent in the brain than in most other organs. HYPOTHESIS TO BE TESTED:
Patrick Allard et al.
Environmental science & technology, 47(4), 2061-2068 (2013-01-24)
The acquisition of essential metals, such as the metal cofactors (molybdenum (Mo) and iron (Fe)) of the nitrogenase, the enzyme responsible for the reduction of dinitrogen (N(2)) to ammonium, is critical to N(2) fixing bacteria in soil. The release of
M L Selley et al.
Neurobiology of aging, 23(3), 383-388 (2002-04-18)
There is evidence that increased blood concentrations of homocysteine may be a risk factor for Alzheimer's disease. (E)-4-hydroxy-2-nonenal (HNE) is a neurotoxic product of lipid peroxidation that is increased in the ventricular fluid and brains of patients with Alzheimer's disease.
Matthias Boll et al.
Biological chemistry, 386(10), 999-1006 (2005-10-13)
The molybdenum enzymes 4-hydroxybenzoyl-CoA reductase and pyrogallol-phloroglucinol transhydroxylase and the tungsten enzyme acetylene hydratase catalyze reductive dehydroxylation reactions, i.e., transhydroxylation between phenolic residues and the addition of water to a triple bond. Such activities are unusual for this class of
Vernon G Thomas et al.
Ecotoxicology and environmental safety, 72(4), 1031-1037 (2009-02-24)
The toxicity of elemental tungsten released from discharged shot was assessed against previous studies that established a 1% toxic threshold for soil organisms. Extremely heavy theoretical shot loadings of 69,000shot/ha were used to generate estimated environmental concentrations (EEC) for two
J-M Serot et al.
Journal of neurology, neurosurgery, and psychiatry, 76(11), 1585-1587 (2005-10-18)
Homocysteine may be involved in the pathogenesis of late onset Alzheimer's disease. It is implicated in the metabolism of several important pathways in the brain. Methylmalonic acid (MMA) is related to the metabolism of branched chained amino acids and fatty
J A Molina et al.
Journal of neural transmission (Vienna, Austria : 1996), 109(7-8), 1035-1044 (2002-07-12)
Thiamine is an essential cofactor for several important enzymes involved in brain oxidative metabolism, such as the alpha-ketoglutarate dehydrogenase complex (KGDHC), pyruvate-dehydrogenase complex (PDHC), and transketolase. Some investigators reported decreased thiamine-diphosphate levels and decreased activities of KGDHC, pyruvate-dehydrogenase complex and
G Galloro et al.
Endoscopy, 45(2), 121-126 (2013-01-12)
Thermal injury of the colonic wall during polypectomy may induce complications such as bleeding and perforation. To date, the role of the snare material in these injuries has not been examined. The aim of this study was to evaluate the
E J Pappert et al.
Neurology, 47(4), 1037-1042 (1996-10-01)
To determine if ventricular cerebrospinal fluid (vCSF) alpha-tocopherol levels in Parkinson's disease (PD) patients can be increased by oral alpha-tocopherol supplementation and whether vCSF levels are linearly related to plasma alpha-tocopherol levels. In spite of its putative neuroprotective properties, alpha-tocopherol
Jian-ping Jia et al.
Chinese medical journal, 117(8), 1161-1164 (2004-09-14)
An important aspect of Alzheimer's disease (AD) is loss or impairment of cholinergic neurons. It is controversial whether there is a similar cholinergic impairment and cerebral deficit of acetylcholine (ACh) in the case of vascular dementia (VD). The purpose of
Shi-Jie Yuan et al.
Scientific reports, 3, 1315-1315 (2013-02-27)
Electrochemically active bacteria (EAB) are ubiquitous in environment and have important application in the fields of biogeochemistry, environment, microbiology and bioenergy. However, rapid and sensitive methods for EAB identification and evaluation of their extracellular electron transfer ability are still lacking.
Jiajun Mei et al.
Journal of the American Chemical Society, 135(1), 424-435 (2012-12-25)
Cp*W(O)(2)(CH(2)SiMe(3)) (1) (Cp* = η(5)-pentamethylcyclopentadienyl) reacts with oxygen atom donors (e.g., H(2)O(2), PhIO, IO(4)(-)) in THF/water to produce TMSCH(2)OH (TMS = trimethylsilyl). For the reaction of 1 with IO(4)(-), the proposed pathway for alcohol formation involves coordination of IO(4)(-) to
A Koutsospyros et al.
Journal of hazardous materials, 136(1), 1-19 (2005-12-14)
Since its discovery, tungsten, a transition element of Group VIb of the Periodic Table of Elements, and its compounds have been considered environmentally benign. Its presence in biological and drinking water samples in Fallon, Nevada, an acute lymphocytic leukemia cluster
Malcolm H Chisholm et al.
Chemical record (New York, N.Y.), 5(5), 308-320 (2005-10-08)
The reaction of M2(O2CBu(t))4 (M = Mo, W) with a dicarboxylic acid in toluene yields compounds of general formula [M2]-O2C-X-CO2-[M2] ([M2] = M2(O2CBu(t))3; X = conjugated spacer). The M2 units are electronically coupled via interactions between the M2 delta and
Aiqin Wang et al.
Accounts of chemical research, 46(7), 1377-1386 (2013-02-21)
With diminishing fossil resources and increasing concerns about environmental issues, searching for alternative fuels has gained interest in recent years. Cellulose, as the most abundant nonfood biomass on earth, is a promising renewable feedstock for production of fuels and chemicals.
M A Lovell et al.
Archives of neurology, 58(3), 392-396 (2001-03-20)
Markers of oxidative stress are increased in cerebrospinal fluid (CSF) of patients with Alzheimer disease (AD), although none of those reported are appropriate diagnostic markers because of the overlap between patients with AD and control subjects. To determine the ratio
José L Domingo
Biological trace element research, 88(2), 97-112 (2002-09-26)
Tungstate is an oxyanion that has biological similarities to vanadate. In recent years, a number of studies have shown the antidiabetic effects of oral tungstate in animal models of diabetes. However, because of the tissue accumulation and potential toxicity derived
A Moser et al.
Journal of the neurological sciences, 131(2), 183-189 (1995-08-01)
We could identify the MPTP-like compound and isoquinoline derivative N-methyl-norsalsolinol (2-MDTIQ) in cerebrospinal fluid (CSF) of patients with Parkinson's disease. The presence of 2-MDTIQ negatively correlated with the disease duration. In order to study the relationship between presence of 2-MDTIQ
C Syburra et al.
Ukrains'kyi biokhimichnyi zhurnal (1999 ), 71(3), 112-115 (1999-12-28)
It is well known that brain and nervous system cells are prone to oxidative damage because of their relatively low content of antioxidants, especially enzymatic ones, and of the high levels of both membrane polyunsaturated fatty acids (PUFA) and iron
L Samuel Keith et al.
Toxicology and industrial health, 23(5-6), 309-345 (2008-04-05)
As part of its mandate, the Agency for Toxic Substances and Disease Registry prepares toxicological profiles on hazardous chemicals found at Comprehensive Environmental Response, Compensation and Liability Act, National Priorities List sites that have the greatest public health impact. These
[The possibility of using inorganic fillers and matrix polymers in materials for radiation protection].
S Ia Lanina et al.
Meditsinskaia tekhnika, (6)(6), 10-13 (2013-01-12)
Souhaila Bouatra et al.
PloS one, 8(9), e73076-e73076 (2013-09-12)
Urine has long been a "favored" biofluid among metabolomics researchers. It is sterile, easy-to-obtain in large volumes, largely free from interfering proteins or lipids and chemically complex. However, this chemical complexity has also made urine a particularly difficult substrate to
R Shukla et al.
The International journal of neuroscience, 116(12), 1391-1402 (2006-12-06)
Evidence from clinical and experimental studies supports the hypothesis of free radical-mediated damage of dopaminergic neurons in the pathology of Parkin's disease (PD). The present study was undertaken to evaluate the role of nitric oxide and oxidative stress in PD.
Ana Navas-Acien et al.
Environmental health perspectives, 113(2), 164-169 (2005-02-03)
Exposure to metals may promote atherosclerosis. Blood cadmium and lead were associated with peripheral arterial disease (PAD) in the 1999-2000 National Health and Nutrition Examination Survey (NHANES). In the present study we evaluated the association between urinary levels of cadmium
Hideki Sugimoto et al.
Chemical Society reviews, 37(12), 2609-2619 (2008-11-21)
Recent characterisation of molybdenum and tungsten enzymes revealed novel structural types of reaction centres, as well as providing new subjects of interest as synthetic chemical analogues. This tutorial review highlights the structure/reactivity relationships of the enzyme reaction centres and chemical
Xiang Li et al.
Journal of biomedical optics, 17(10), 106005-106005 (2012-12-12)
The catheter-based intravascular photoacoustic (IVPA) imaging for diagnosing atherosclerosis, which can provide optical absorption contrast of the arterial wall besides acoustic scattering contrast from the conventional intravascular ultrasound (IVUS) imaging, has been intensively researched recently. The resolution of IVPA is
D A Loeffler et al.
Journal of neural transmission. Parkinson's disease and dementia section, 9(1), 45-53 (1995-01-01)
Though depletion of CSF homovanillic acid (HVA) concentration has often been regarded as a direct indicator of dopamine (DA) deficiency in Parkinson's Disease (PD), CSF HVA is normal in mildly affected patients. To explore why, we measured DA and its
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