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<abstract_text><p>The cerebrovascular and anti-ischemic effects of dopamine and synthetic docosahexaenoyldopamine (DHA-DA) and the GABA-DHA-DA conjugate (OXL1220) were compared and found to differ. Dopamine and DHA-DA increased bl...
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<abstract_text><p>The cerebrovascular and anti-ischemic effects of dopamine and synthetic docosahexaenoyldopamine (DHA-DA) and the GABA-DHA-DA conjugate (OXL1220) were compared and found to differ. Dopamine and DHA-DA increased blood flow in intact and ischemic brain that was associated with pronounced hypertensive reactions. The latter inhibited dopamine transporter with IC50 - 29 mu M but was practically inactive as a ligand for dopamine receptors. OXL1220 produced a selective vasodilating effect on blood flow in brain subjected to transient global ischemia. Only OXL1220 competed in vitro for specific binding sites of [H-3]-gabazine in rat-brain GABA(A)-receptors. Therefore, conjugation of a neuromediator (GABA) to the DHA-DA changed the dopaminergic activity of the compound to GABA-ergic with respect to vascular tone in ischemic brain.</p></abstract_text>
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Formation of Cu(II) and Ni(II) complexes of 1,2,-dihydroxy-9,10-anthraquinone (DHA) has been studied by the spectrophotometric method. Both the metals form stable complexes of the type [M(LH)3]- where LHH1 represents DHA. The effe...
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Formation of Cu(II) and Ni(II) complexes of 1,2,-dihydroxy-9,10-anthraquinone (DHA) has been studied by the spectrophotometric method. Both the metals form stable complexes of the type [M(LH)3]- where LHH1 represents DHA. The effective stability constant of the Cu(II) complex is 5.135 × 1029 while that of the Ni(II) complex is 3.446 × 1025. These complexes, unlike free DHA, do not catalyze the flow of electrons from NADH to molecular O2 through NADH dehydrogenase.
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A novel polymeric dye containing an anthraquinone ring was prepared by solution polycondensation. The molecule geometry was fully optimized on the basis of the AM1 method. The hydrogen bond was formed and retained coplanarity in t...
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A novel polymeric dye containing an anthraquinone ring was prepared by solution polycondensation. The molecule geometry was fully optimized on the basis of the AM1 method. The hydrogen bond was formed and retained coplanarity in the molecular structure. In its UV spectrum, a large hypsochromic shift and a hypochromic effect were observed due to polyesterification. The polymeric dye was also characterized by means of IR and TG. Its thermal degradation mechanism was elucidated.
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The thraustochytrid-like microorganism,strain 12B,cultivated in peptone,yeast extract,and 8% (w/v) glucose in 50% (v/v) seawater,accumulated docosahexaenoic acid (DHA)-rich triacylglycerol (TAG) at 67% of total lipid.When these TA...
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The thraustochytrid-like microorganism,strain 12B,cultivated in peptone,yeast extract,and 8% (w/v) glucose in 50% (v/v) seawater,accumulated docosahexaenoic acid (DHA)-rich triacylglycerol (TAG) at 67% of total lipid.When these TAG-accumulated cells were cultivated in glucose-deficient medium,dry cell weight (3 mg per ml culture) increased approximately 3-fold relative to baseline but the TAG/total lipid decreased to 5%.At the same time,the amount of phospholipid (5 mg) per whole culture also increased 3-fold.Hence,phospholipid/ total lipid increased from 13% to 67%.High levels of DHA (more than 50% of total) were maintained in phosphatidylcholine.
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Background: The Diels-Alder reaction has played a fundamental role in advancing synthetic chemistry over the years and continues to greatly impact modern synthetic methodology. Ever increasing interest in the application of ionic ...
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Background: The Diels-Alder reaction has played a fundamental role in advancing synthetic chemistry over the years and continues to greatly impact modern synthetic methodology. Ever increasing interest in the application of ionic liquids (ILs) as catalyst and solvents in organic synthesishas provided the impetus to explore their application in Diels-Alder chemistry with the goal to improve efficiency as well as chemo-, regio- and enantio-selectivity. Objective: The review focuses on recent progress in the area of IL-mediated Diels-Alder reactions through illustrativeexamples that demonstrate their efficacy as solvent and catalysts. Conclusion: It is clear from the review of the topic that a vast amount of work has been done in this area, employing diverse types of ILs which were employed either alone or in conjunction with Lewis-acids, metal ions,chiral additives, organocatalysts, and/or other additives. The results in comparison to conventional solvents have demonstrated improved yields, faster rates, as well as improved regio- and enantioselectivity. These attributes along with the advantages associated with recycling/reuse clearlypoint to ILs as superior media for Diels-Alder chemistry. Much of the emphasis has been on synthesis but some fundamental mechanistic work aimed at understanding rate enhancement and endo-selectivity have also been reported.
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Investigation of plasmid-borne AmpC beta-lactamase genes in Escherichia coli and Klebsiella spp. revealed bla(CMY-2)- like genes predominantly in E. coil and bla(DHA) genes equally distributed between both species. This distributi...
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Investigation of plasmid-borne AmpC beta-lactamase genes in Escherichia coli and Klebsiella spp. revealed bla(CMY-2)- like genes predominantly in E. coil and bla(DHA) genes equally distributed between both species. This distribution remained stable over time, but bla(ACT/MIR)-like genes, initially common in Klebsiella spp., were not identified in more recent isolates. (C) 2015 Elsevier Inc. All rights reserved.
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Under the assumption of large scale antenna, we analyze the sum rate of circular layout distributed antenna systems (CL-DAS). First, we propose a concept of virtual base station and an expected large scale fading (E-LSF) for an ar...
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Under the assumption of large scale antenna, we analyze the sum rate of circular layout distributed antenna systems (CL-DAS). First, we propose a concept of virtual base station and an expected large scale fading (E-LSF) for an arbitrarily located user as a function of the locations of users and distributed antennas and a path loss exponent. Based on E-LSF, we derive an approximated sum rate of CL-DAS whose form is identical to the sum rate of centralized multiple-input multiple-output (C-MEMO) systems. These results make it possible that the sum rate of CL-DAS with arbitrary beamforming schemes or power allocation algorithms can be evaluated using the existing approaches for C-MIMO systems. Simulation results verify that our analyses with E-LSF are valid for practical systems.
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The D-DNA double helix model of poly(dA-dT).poly(dA-dT) proposed in the literature is not in accordance with some notable experimental facts and physicochemical conditions to which it is related. Thus, the fibre X-ray diffraction ...
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The D-DNA double helix model of poly(dA-dT).poly(dA-dT) proposed in the literature is not in accordance with some notable experimental facts and physicochemical conditions to which it is related. Thus, the fibre X-ray diffraction pattern of D-DNA obtained at a relative humidity lower than that giving the A-DNA form is singularly not taken into account when one assumes that there is only one D structure of B-DNA type. We rather suggest that there are actually two different forms of D-DNA, namely DA which partakes in the D-A-B transitions and DB associated with the D-B change of conformation. Although these two DNA structures have the same helical parameters (pitch and number of residues per turn), in agreement with X-ray data, their detailed conformations are considerably different. Whereas DB is indeed the structure generally defined as D-DNA, a critical analysis based on a comparison between different possible DNA double helices leads us to propose dihedral angles, a set of atomic coordinates and a stereo view of another new form of D-DNA, the DA structural model. It is a right-handed double helix with a dinucleotide as the repeat unit. The furanose rings are of the A-DNA type (C3′ endo) and the bases are hydrogen bonded according to the reversed Hoogsteen pairing. Such a disposition renders the DA model unsuitable for poly(dI-dC).poly(dI-dC), the other alternating polynucleotide observed in the DB structure. The consistency of these two different D-DNA structures of poly(dA-dT).poly(dA-dT) with the general aspects of hydration and helix-helix transitions of DNA, as well as with the conformational variability of AT base sequences, is discussed.
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The kinetics of the hydrolysis of p-nitrophenyl diphenyl phosphate (PNPDPP) by hydroxamate ions (R'(CO)N(RO-) such as octanohydroxamate (OHA(-)) and decanohydroxamate (DHA(-)) was investigated in dioctadecyldimethylammonium chlori...
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The kinetics of the hydrolysis of p-nitrophenyl diphenyl phosphate (PNPDPP) by hydroxamate ions (R'(CO)N(RO-) such as octanohydroxamate (OHA(-)) and decanohydroxamate (DHA(-)) was investigated in dioctadecyldimethylammonium chloride (DODAC) and didodecyldimethylammonium bromide (DDAB) vesicles. The physicochemical properties of these surfactants were studied by conductivity and fluorescence measurements at 300K. The hydrolysis of PNPDPP was studied in a vesicular system by using hydroxamate ions (OHA(-) and DHA(-)) at 300K. The different catalytic effects of hydroxamate ions for the hydrolysis of PNPDPP in the vesicles were determined. All reactions followed pseudofirst-order kinetics. The reactivity of DHA(-) was found to be higher than that of OHA(-) in the vesicular system toward the cleavage of phosphate ester. Further, the binding constants (K) and free energy change (G) for the associations of PNPDPP with DODAC and DDAB vesicles were determined spectrophotometrically as well as from the Benesi-Hildebrand (B-H) plots. The pseudophase model was applied for the quantitative treatment of the kinetic data in the vesicle systems.
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