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131.
Manoj Kumar Jaiswal Wolf-Dieter Zech Miriam Goos Christine Leutbecher Alberto Ferri Annette Zippelius Maria Teresa Carrì Roland Nau Bernhard U Keller 《BMC neuroscience》2009,10(1):64
Background
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the selective loss of motor neurons (MN) in the brain stem and spinal cord. Intracellular disruptions of cytosolic and mitochondrial calcium have been associated with selective MN degeneration, but the underlying mechanisms are not well understood. The present evidence supports a hypothesis that mitochondria are a target of mutant SOD1-mediated toxicity in familial amyotrophic lateral sclerosis (fALS) and intracellular alterations of cytosolic and mitochondrial calcium might aggravate the course of this neurodegenerative disease. In this study, we used a fluorescence charged cool device (CCD) imaging system to separate and simultaneously monitor cytosolic and mitochondrial calcium concentrations in individual cells in an established cellular model of ALS. 相似文献132.
We have studied the energetics and magnetism in Cr-doped (ZnTe)12 clusters by first principles density functional calculations. Total energy calculations suggest that it is energetically most favourable for Cr atoms to substitute at Zn sites. Both ferromagnetic and anti-ferromagnetic coupling between the Cr atoms exist depending on the Cr-Cr distance in the clusters. The magnetic exchange coupling between Cr atoms is short-ranged. 相似文献
133.
Varughese Philip E. Manoj M. R. Prathapachandra Kurup Munirathinam Nethaji 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m488-m490
The VV atom in the title complex, [V(C16H16N5S)O2], is five‐coordinate in a highly distorted square‐pyramidal geometry, with the pyridyl N, the azomethine N and the thiolate S atoms of the di‐2‐pyridyl ketone N4,N4‐(butane‐1,4‐diyl)thiosemicarbazone ligand and one oxo ligand occupying the basal coordination positions, while the second oxo ligand occupies the apical position. The molecules are interconnected by weak intermolecular interactions, mainly of the C—H⋯O type, involving the oxo atoms. 相似文献
134.
K. Manoj S. Devaraj R. G. Gonnade M. M. Bhadbhade M. S. Shashidhar 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):o628-o630
The centrosymmetric O—H⋯O‐bonded head‐to‐head dimers of the title compound, C21H22O6, are linked together via bifurcated C—H⋯O interactions along the a axis and via favourable C—H⋯π interactions along the b axis in the crystal structure. 相似文献
135.
Three new ditopic receptors 3a-c based on thiacalix[4]arene of 1,3 alternate conformation possessing two different complexation sites have been designed and synthesized for both soft and hard metal ions. The imino nitrogens bind soft metal ion (Ag+/Pb2+/Cu2+) and the crown moiety binds K+ ion. The preliminary investigations show that 3a-c behave as ditopic receptors for Ag+/K+, Pb2+/K+, and Cu2+/K+ ions, respectively. In all the three receptors it was observed that the formation of 3a·Ag+/3b·Pb2+/3c·Cu2+ complex triggers the decomplexation of K+ ion from crown moiety and acts as a gateway, which regulates the binding of alkali metal to crown moiety. Thus, allosteric binding between metal ions ‘switch off’ the recognition ability of crown ether ring. 相似文献
136.
An expeditious one-pot synthesis of 2,3-diaryl/2-aryl-3-heteroaryl-1,3-thiazolidin-4-ones and 1-aryl-1H,3H-thiazolo[3,4-a]benzimidazoles have been accomplished by condensing hetero/aromatic amine, 2-mercaptoacetic acid, aromatic aldehyde and 1,2-phenylenediamine, 2-mercaptoacetic acid and aromatic aldehyde, respectively, in ionic liquids, viz, 1-butyl-3-methyl-imidazolium tetrafluoroborate and 1-methoxyethyl-3-methylimidazolium trifluoroacetate. 相似文献
137.
Three different derivatives of macrocyclic tetraimine Schiff's base have been synthesized and explored as a neutral ionophores for preparing poly(vinyl chloride) based membrane sensors selective to Dy3+. The addition of sodium tetraphenyl borate and various plasticizers, viz., o-NPOE, DBP, DBBP, DOP and CN has been found to substantially improve the performance of the sensors. The best performance was obtained with the sensor no. 1 having membrane of Schiff's base (SL-1) with composition (w/w) SL-1 (4.5%): PVC (30.5%): o-NPOE (59.5%): NaTPB (5.5%). This sensor exhibits Nernstian response with slope 19.4 mV/decade of activity in the concentration range of 10−8 to 1.0 × 10−2 M Dy3+, performs satisfactorily over wide pH range of (2.8-7.2) with a fast response time (10 s). The sensor was also found to work satisfactorily in partially non-aqueous media up to 20% (v/v) content of acetonitrile, methanol or ethanol. The proposed sensor can be used over a period of 1.5 months without significant drift in potentials. The sensor has been also utilized for the determination of Dy3+ level in different soil samples. 相似文献
138.
139.
The geodesic and induced path transit functions are the two well-studied interval functions in graphs. Two important transit functions related to the geodesic and induced path functions are the triangle path transit functions which consist of all vertices on all u,v-shortest (induced) paths or all vertices adjacent to two adjacent vertices on all u,v-shortest (induced) paths, for any two vertices u and v in a connected graph G. In this paper we study the two triangle path transit functions, namely the IΔ and JΔ on G. We discuss the betweenness axioms, for both triangle path transit functions. Also we present a characterization of pseudo-modular graphs using the transit function IΔ by forbidden subgraphs. 相似文献
140.
Nirogi RV Kandikere VN Shukla M Mudigonda K Maurya S Boosi R 《Rapid communications in mass spectrometry : RCM》2006,20(11):1695-1700
A simple, sensitive and rapid high-performance liquid chromatography/positive electrospray ionization tandem mass spectrometry method was developed and validated for the assay of clopidogrel in human plasma. Following liquid-liquid extraction, the analytes were separated using an isocratic mobile phase on a reversed-phase column and analyzed by mass spectrometry in the multiple reaction monitoring mode using the respective [M+H](+) ions, m/z 322/212 for clopidogrel and m/z 264/154 for the internal standard. The assay exhibited a linear dynamic range of 5-6000 pg/mL for clopidogrel in human plasma. The lower limit of quantification was 5 pg/mL with a relative standard deviation of less than 8%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 2.5 min for each sample made it possible to analyze more than 400 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies. 相似文献