Mol-ecular structure of tris-[(6-bromo-pyridin-2-yl)meth-yl]amine.

Coordination compounds of polydentate nitro-gen ligands with metals are used extensively in research areas such as catalysis, and as models of complex active sites of enzymes in bioinorganic chemistry. Tris(2-pyridyl-meth-yl)amine (TPA) is a tripodal tetra-dentate ligand that is known to form coordination compounds with metals, including copper, iron and zinc. The related compound, tris-[(6-bromo-pyridin-2-yl)meth-yl]amine (TPABr), CHBrN, which possesses a bromine atom on the 6-position of each of the three pyridyl moieties, is also known but has not been heavily investigated.

Crystal structure of tetra-kis-(μ-2-hy-droxy-3,5-di-isoprop-yl-benzoato)bis-[(dimethyl sulfoxide)copper(II)].

Metal complexes of 3,5-diiso-propyl-salicylate are reported to have anti-inflammatory and anti-convulsant activities. The title binuclear copper complex, [Cu(CHO)(CHOS)] or [Cu(II)(3,5-DIPS)(DMSO)], contains two five-coordinate copper atoms that are bridged by four 3,5-diiso-propyl-salicylate ligands and capped by two axial dimethyl sulfoxide (DMSO) moieties. Each copper atom is attached to four oxygen atoms in an almost square-planar fashion, with the addition of a DMSO ligand in an apical position leading to a square-pyramidal arrangement.

Analysis of Sex-Specific Prostanoid Production Using a Mouse Model of Selective Cyclooxygenase-2 Inhibition.

Background: Prostanoids are a family of lipid mediators formed from arachidonic acid by cyclooxygenase enzymes and serve as biomarkers of vascular function. Prostanoid production may be different in males and females indicating that different therapeutic approaches may be required during disease.

Objectives: We examined sex-dependent differences in COX-related metabolites in genetically modified mice that produce a cyclooxygenase-2 (COX2) enzyme containing a tyrosine 385 to phenylalanine (Y385F) mutation.

Crystal structure of hexa-μ-chlorido-μ-oxido-tetra-kis-{[1-(2-hy-droxy-eth-yl)-2-methyl-5-nitro-1-imidazole-κ ]copper(II)} containing short NO⋯NO contacts.

The title tetra-nuclear copper complex, [CuClO(CHNO)] or [CuClO-(MET)] [MET is 1-(2-hy-droxy-eth-yl)-2-methyl-5-nitro-1-imidazole or metronidazole], contains a tetra-hedral arrangement of copper(II) ions. Each copper atom is also linked to the other three copper atoms in the tetra-hedron bridging chloride ions. A fifth coordination position on each metal atom is occupied by a nitro-gen atom of the monodentate MET ligand.

Crystal structure of hexa-kis-(dimethyl sulfoxide-κ)cobalt(II) bis-[tri-chlorido-(quinoline-κ)cobaltate(II)].

There are few reports that describe crystal structures of compounds containing cobalt complexed to either dimethyl sulfoxide (MeSO) or quinoline (CHN). The title compound, [Co(CHOS)][CoCl(CHN)], is a cobalt salt in which the metal ion is complexed to both MeSO and quinoline. In particular, we observed that anhydrous cobalt(II) chloride reacts with quinoline in MeSO to form a salt that is to be formulated as [Co(MeSO)]{[CoClquinoline]}.

Crystal structure of di-μ-chlorido-bis-[chlorido-bis-(1,2-dimethyl-5-nitro-1-imidazole-κ)copper(II)] acetonitrile disolvate.

1,2-Dimethyl-5-nitro-imidazole (dimetridazole, dimet) is a compound that belongs to a class of nitro-imidazole drugs that are effective at inhibiting the activity of certain parasites and bacteria. However, there are few reports that describe structures of compounds that feature metals complexed by dimet. Therefore, we report here that dimet reacts with CuCl·HO to yield a chloride-bridged copper(II) dimer, [CuCl(CHNO)] or [Cu(μ-Cl)Cl(dimet)].

Eicosapentaenoic Acid Modulates Trichomonas vaginalis Activity.

Trichomonas vaginalis is a sexually transmitted parasite and, while it is often asymptomatic in males, the parasite is associated with disease in both sexes. Metronidazole is an effective treatment for trichomoniasis, but resistant strains have evolved and, thus, it has become necessary to investigate other possible therapies. In this study, we examined the effects of native and oxidized forms of the sodium salts of eicosapentaenoic, docosahexaenoic, and arachidonic acids on T.

Crystal structure of metronidazolium tetra-chlorido-aurate(III).

Metronidazole (MET) [systematic names: 1-(2-hy-droxy-eth-yl)-2-methyl-5-nitro-1H-imidazole and 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethanol] is a medication that is used to treat infections from a variety of anaerobic organisms. As with other imidazole derivatives, metronidazole is also susceptible to protonation. However, there are few reports of the structures of metronidazolium derivatives.

Crystal structure of bis-[1-(2-hy-droxy-eth-yl)-2-methyl-5-nitro-1H-imidazole-κN (3)]silver(I) tetra-fluorido-borate methanol monosolvate.

1-(2-Hy-droxy-eth-yl)-2-methyl-5-nitro-1H-imidazole (metronidazole, MET) is a medication that is used to treat infections by a variety of anaerobic organisms, but there are relatively few reports of the structures of metal compounds that exhibit coordination of metronidazole. We have demonstrated that MET reacts with AgBF4 to give [Ag(MET)2]BF4·CH3OH, in which the Ag(I) cation is coordinated by two MET ligands with a trans arrangement. The structure of [Ag(MET)2]BF4 exhibits some inter-esting differences from its nitrate counterpart, [Ag(MET)2]NO3 [Fun et al.

Mass spectrometric analysis of oxidized eicosapentaenoic Acid sodium salt.

Eicosapentaenoic acid (EPA) is an omega-3 polyunsaturated fatty acid (PUFA) with 20 carbon atoms and 5 carbon-carbon double bonds. Mammalian cells cannot synthesize long chain PUFAs such as EPA de novo, and, thus, the most effective way to enrich cells in EPA is by dietary intake of fish oils. EPA supplementation causes an increase in its concentration in plasma lipids and in cell membrane phospholipids.

Inducible nitric oxide synthase provides protection against injury-induced thrombosis in female mice.

Nitric oxide (NO) is an important vasoactive molecule produced by three NO synthase (NOS) enzymes: neuronal (nNOS), inducible (iNOS), and endothelial NOS (eNOS). While eNOS contributes to blood vessel dilation that protects against the development of hypertension, iNOS has been primarily implicated as a disease-promoting isoform during atherogenesis. Despite this, iNOS may play a physiological role via the modulation of cyclooxygenase and thromboregulatory eicosanoid production.

Inducible nitric oxide synthase gene deletion exaggerates MAPK-mediated cyclooxygenase-2 induction by inflammatory stimuli.

Cyclooxygenase (COX)-2 and inducible nitric oxide (NO) synthase (iNOS) are responsive to a wide array of inflammatory stimuli, have been localized to vascular smooth muscle cells (SMCs), and are intimately linked to the progression of vascular disease, including atherosclerotic lesion formation. We and others have shown that the production and subsequent impact of COX products appear to be correlative with the status of NO synthesis. This study examined the impact of inflammation-driven NO production on COX-2 expression in SMCs.

Physical evidence for substrate binding in preventing cyclooxygenase inactivation under nitrative stress.

Prostaglandin biosynthesis is catalyzed by two spatially and functionally distinct active sites in cyclooxygenase (COX) enzymes. Despite the crucial role of COXs in biology, molecular details regarding the function and regulation of these enzymes are incompletely defined. Reactive nitrogen species, formed during oxidative stress, produce modifications that alter COX functionalities and prostaglandin biosynthesis.

Micro ATR-FTIR spectroscopic imaging of atherosclerosis: an investigation of the contribution of inducible nitric oxide synthase to lesion composition in ApoE-null mice.

Inducible nitric oxide synthase (iNOS) has previously been shown to contribute to atherosclerotic lesion formation and protein nitration. Micro attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopic imaging was applied ex vivo to analyse lesions in atherosclerotic (ApoE-/-) mice. Histologies of cardiovascular tissue of ApoE-/- mice that contain the gene for iNOS and ApoE-/- mice without iNOS (ApoE-/-iNOS-/- mice) were examined.

Atherosclerosis: A Link Between Lipid Intake and Protein Tyrosine Nitration.

Atherosclerosis, a disease characterized by plaque formation in the arterial wall that can lead to heart attack and stroke, is a principal cause of death in the world. Since the 1990's, protein nitrotyrosine formation has been known to occur in the atherosclerotic plaque. This potentially damaging reaction occurs as a result of tyrosine modification by reactive nitrogen species, such as nitrogen dioxide radical, which forms upon peroxynitrite decomposition or nitrite oxidation by hydrogen peroxide-activated peroxidase enzymes.

Profound biopterin oxidation and protein tyrosine nitration in tissues of ApoE-null mice on an atherogenic diet: contribution of inducible nitric oxide synthase.

Diminished nitric oxide (NO) bioactivity and enhanced peroxynitrite formation have been implicated as major contributors to atherosclerotic vascular dysfunctions. Hallmark reactions of peroxynitrite include the accumulation of 3-nitrotyrosine (3-NT) in proteins and oxidation of the NO synthase (NOS) cofactor, tetrahydrobiopterin (BH(4)). The present study sought to 1) quantify the extent to which 3-NT accumulates and BH(4) becomes oxidized in organs of apolipoprotein E-deficient (ApoE(-/-)) atherosclerotic mice and 2) determine the specific contribution of inducible NOS (iNOS) to these processes.

Reprint of "oxidative alterations of cyclooxygenase during atherogenesis" [Prostag. Oth. Lipid. M. 80 (2006) 1-14].

Nitric oxide (*NO) and eicosanoids are critical mediators of physiological and pathophysiological processes. They include inflammation and atherosclerosis. *NO production and eicosanoid synthesis become disrupted during atherosclerosis and thus, it is important to understand the mechanisms that may contribute to this outcome.

Oxidative alterations of cyclooxygenase during atherogenesis.

Nitric oxide (*NO) and eicosanoids are critical mediators of physiological and pathophysiological processes. They include inflammation and atherosclerosis. *NO production and eicosanoid synthesis become disrupted during atherosclerosis and thus, it is important to understand the mechanisms that may contribute to this outcome.

Heme catalyzes tyrosine 385 nitration and inactivation of prostaglandin H2 synthase-1 by peroxynitrite.

The mechanism by which the inflammatory enzyme prostaglandin H(2) synthase-1 (PGHS-1) deactivates remains undefined. This study aimed to determine the stabilizing parameters of PGHS-1 and identify factors leading to deactivation by nitric oxide species (NO(x)). Purified PGHS-1 was stabilized when solubilized in beta-octylglucoside (rather than Tween-20 or CHAPS) and when reconstituted with hemin chloride (rather than hematin).

Inducible nitric oxide synthase mediates prostaglandin h2 synthase nitration and suppresses eicosanoid production.

Nitric oxide (NO) modulates the biological levels of arachidonate-derived cell signaling molecules by either enhancing or suppressing the activity of prostaglandin H(2) isoforms (PGHS-1 and PGHS-2). Whether NO activates or suppresses PGHS activity is determined by alternative protein modifications mediated by NO and NO-derived species. Here, we show that inducible NO synthase (iNOS) and PGHS-1 co-localize in atherosclerotic lesions of ApoE(-/-) mouse aortae.

Involvement of the mitogen-activated protein kinase cascade in peroxynitrite-mediated arachidonic acid release in vascular smooth muscle cells.

Eicosanoid production is reduced when the nitric oxide (NO.) pathway is inhibited or when the inducible NO synthase gene is deleted, indicating that the NO. and arachidonic acid pathways are linked.

Tyrosine nitration in prostaglandin H(2) synthase.

In this study, we investigated the effects of various nitrogen oxide (NO(x)) species on the extent of prostaglandin H(2) synthase-1 (PGHS-1) nitration in purified protein and in vascular smooth muscle cells. We also examined PGHS-1 activity under these conditions and found the degree of nitration to correlate inversely with enzyme activity. In addition, since NO(x) species are thought to invoke damage during the pathogenesis of atherosclerosis, we examined human atheromatous tissue for PGHS-1 nitration.