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The primary goal of this research is to study the Cattaneo-Christov heat flux model on the impacts of mass and energy transit of MHD Casson-Carreu nanofluid through a permeable vertical accelerating plate with Soret and Dufour mechanism. The non-Newtonian fluids flowed over the porous vertical plate to reach the boundary layer in this investigation. In order to understand the physical model, partial differential equations (PDEs) are used. To get a linked nonlinear set of ordinary differential equations (ODEs), we reduced this set of PDEs by using similarity variables. SHAM, a spectrum basis technique, was utilized to solve these modified equations to understand the physical significance. A good method is to utilize SHAM to decouple the coupled nonlinear ODE systems and divide them into linear and nonlinear equation sets since this helps to separate the systems. As a result, the two non-Newtonian fluids (Carreu and Cassin) flow together through the vertical wall and into the boundary layer, where different parameters’ impacts are scrutinized. The current results showed that an upturn in the Casson parameter (β) degenerates the boundary layer velocity and the total thickness. Upturn in the Weissenberg number (We) on the other hand, raises the velocities and temperatures in both directions. Additionally, increasing the Soret and Dufour parameters sped up the velocity graph.

The oxidation of glyoxylic acid (HGl) by MnIVL {L4− = tetra deprotonated 1,8-bis(2-hydroxybenzamido)-3,6-diazaoctane} was investigated in the pH range 1.67–10.18, at 25–45 °C and 0.5 M ionic strength. The reaction exhibited biphasic kinetics with MnIIIL− as the reactive intermediate. MnIV was reduced to MnII. The products of oxidation of HGl were identified as formic acid and CO2 in acidic medium, and oxalate in basic medium, consistent with the stoichiometry: −Δ[MnIV]/−Δ[HGl] = 1. In acidic medium, both MnIVL and MnIIIL− formed outer-sphere adducts with the neutral HGl {HC(OH)2COOH} molecule, with an association constant Qav of 28 and 70 M−1, respectively. A similar adduct formation was not observed for the glyoxylate mono anion {Gl−, CH(OH)2(CO2−)} and glyoxylate dianion {Gl2−, CH(OH)(O−)CO2−}. The rate and activation parameters for the various paths are reported and an outer-sphere electron transfer mechanism is suggested.

Objective— Oxidative stress contributes to the pathogenesis of many diseases, including atherosclerosis and sepsis. We have previously described a novel class of therapeutic compounds with antioxidant and antiinflammatory properties. However, at present, the intracellular targets of these compounds have not been identified. The purpose of this study was to elucidate the mechanism by which 2 structurally-related antioxidants (AGI-1067 and AGI-1095) inhibit LPS induction of tissue factor (TF) expression in human monocytic cells and endothelial cells. Methods and Results— We found that succinobucol (AGI-1067) and AGI-1095 inhibited LPS induction of TF expression in both monocytic cells and endothelial cells. These compounds also reduced LPS induction of nuclear AP-1 and expression of Egr-1 without affecting nuclear translocation of NF-κB. Importantly, these antioxidants inhibited LPS activation of the redox-sensitive kinase, apoptosis signal-regulating kinase-1 (ASK1) and the mitogen-activated protein kinases (MAPKs) p38, ERK1/2, and JNK1/2. Conclusions— AGI-1067 and AGI-1095 inhibit TF gene expression in both monocytic cells and endothelial cells through a mechanism that involves the inhibition of the redox-sensitive MAP3K, ASK1. These compounds selectively reduce the activation/induction of MAPK, AP-1, and Egr-1 without affecting NF-κB nuclear translocation.

We examined induced expression of the 5-lipoxygenase-activating protein (FLAP), which is critical for leukotriene synthesis in mononuclear phagocytes. Prolonged exposure to the bacterial component, lipopolysaccharide (LPS), increased FLAP gene transcription, mRNA expression, and protein expression in the human monocyte-like THP-1 cell line. Activation and inhibition of the NF-kappaB pathway modulated LPS induction of FLAP gene expression. An NF-kappaB-mediated mechanism of action was supported by overexpression of dominant-negative IkappaBalpha and p50/p65 proteins. EMSA/supershift and DNase I footprint analyses revealed that p50 binds to an NF-kappaB site located in the proximal FLAP promoter, while chromatin immunoprecipitation assays demonstrated that LPS induced binding of p50 but not of p65. Moreover, EMSA/supershift analyses demonstrated that LPS induced time-dependent binding of THP-1 nuclear extracts (containing p50) to this promoter region. Mutation of the NF-kappaB site decreased basal promoter activity and abolished the p50- and p65-associated induction. EMSA/supershift analyses also demonstrated that LPS induced binding of THP-1 nuclear extracts [containing CCAAT/enhancer binding protein (C/EBP)-alpha, -delta, and -epsilon] to a C/EBP site located adjacent to the NF-kappaB site in the FLAP promoter. We conclude that LPS enhances FLAP gene expression via both NF-kappaB- and C/EBP-mediated transcriptional mechanisms in mononuclear phagocytes.

Glucocorticoids, such as dexametha- sone (Dex), are used clinically in the treatment of various inflammatory diseases. Dex acts by inhib- iting the expression of inflammatory mediators, such as tumor necrosis factor (TNF-) and monocyte chemoattractant protein-1 (MCP-1). It is surprising that Dex enhances bacterial lipopoly- saccharide (LPS) induction of tissue factor (TF) expression in human monocytic cells. TF is a trans- membrane glycoprotein that activates the coagula- tion protease cascade. In this study, we analyze the mechanism by which Dex enhances LPS-induced TF expression in human monocytic cells. We found that Dex reduced LPS-induced TF gene transcrip- tion but increased the stability of TF mRNA. Dex decreased the stability of MCP-1 mRNA and did not affect TNF- mRNA stability. Finally, we showed that Dex increased the stability of a tran- script consisting of the final 297 nucleotides of the TF mRNA in in vitro decay assays. This region contains AU-rich elements that regulate mRNA sta- bility and may mediate the Dex response. There- fore, despite an inhibition of TF gene transcrip- tion, Dex enhances TF expression in human mono- cytic cells by increasing the stability of TF mRNA. J. Leukoc. Biol. 76: 145-151; 2004.

We examined expression of the 5-lipoxygenase activating protein (FLAP), which is critical for inflammatory cell leukotriene synthesis. A 3.4-kb segment of the FLAP gene 5'-untranslated region accounted for a 22-fold increase in promoter activity when transfected into the monocyte-like cell line, THP-1, and demonstrated no activity in non-inflammatory cells. Virtually all of the promoter activity was mediated by the first 134 bp upstream of the transcription start site, a region that contains CCAAT/enhancer-binding proteins (C/EBP) consensus binding sites, at -36 to -28 bp (distal) and -25 to -12 bp (proximal). DNase I footprint analyses demonstrated THP-1 nuclear extract proteins bind to the proximal site. Electrophoretic mobility shift assay analyses revealed that C/EBP alpha, delta, and epsilon bind to the proximal site and C/EBP alpha and epsilon bind to the distal site, constitutively. Transfection studies indicated that mutation of both the proximal and distal sites decreased constitutive FLAP promoter activity. Overexpression of C/EBP alpha, beta, and delta transactivated promoter activity and increased native FLAP mRNA accumulation. Mutation of both C/EBP sites essentially abolished promoter induction by C/EBP overexpression. Tumor necrosis factor (TNF) alpha induced FLAP mRNA expression, FLAP promoter activity, and C/EBP alpha, delta, and epsilon binding to the proximal and distal promoter consensus sites. Chromatin immunoprecipitation assays demonstrated that C/EBP alpha, delta, and epsilon bound to this region of the 5'-untranslated region, whereas C/EBP beta does not bind even under conditions of overexpression and stimulation. We conclude that the FLAP gene is transactivated by members of the C/EBP family of transcription factors in inflammatory cells and that these factors play an important role in FLAP gene induction by TNFalpha.

The pyrazolyl group has been used in conjuction with the amido group for the design and synthesis of a new series of bifunctional ligands, PzCH2C(O)NHR, where Pz = 1-pyrazolyl/3,5-dimethyl-1-pyrazolyl; R = H(APz/ADMPz), Me(MAPz/MADMPz), Ph(PAPz/PADMPz). These ligands have been characterized based on their mass, IR, 1H and 13C{H} NMR spectra and their complexes with PdII and PtII reported. Simple mixing of aqueous solutions of K2[MCl4] (M = Pd, Pt) and the pyrazole amide in a 1:2 ratio gave neutral complexes of the type cis-MCl2L2. Alternatively, an aqueous solution of K2[MCl4] added to an aqueous solution of ligand at pH ∼ 8.0 afforded neutral bis-chelates of the type ML2. A neutral monodentate coordination (LH) has been assigned for the ligand in the former complexes, whereas uninegative bidentate coordination through deprotonated amide nitrogen has been assigned in the latter complexes.

A number of Cu(II) complexes of peptide derivatives that coordinate via N-deprotonation at the C-terminal amino acid residue have been characterized by titrimetry and the Cu(III)-Cu(II) electrochemical potentials. Reaction of these complexes with persulfate induces oxidative decarboxylation and hydrolysis of the resulting N-acylimines to carboxamide and either HCHO, CH 3 CHO, or acetone depending on the identity of the C-terminal residue

We examined expression of the 5-lipoxygenase activating protein (FLAP), which is critical for inflammatory cell leukotriene synthesis. A 3.4-kb segment of the FLAP gene 5'-untranslated region accounted for a 22-fold increase in promoter activity when transfected into the monocyte-like cell line, THP-1, and demonstrated no activity in non-inflammatory cells. Virtually all of the promoter activity was mediated by the first 134 bp upstream of the transcription start site, a region that contains CCAAT/enhancer-binding proteins (C/EBP) consensus binding sites, at -36 to -28 bp (distal) and -25 to -12 bp (proximal). DNase I footprint analyses demonstrated THP-1 nuclear extract proteins bind to the proximal site. Electrophoretic mobility shift assay analyses revealed that C/EBP alpha, delta, and epsilon bind to the proximal site and C/EBP alpha and epsilon bind to the distal site, constitutively. Transfection studies indicated that mutation of both the proximal and distal sites decreased constitutive FLAP promoter activity. Overexpression of C/EBP alpha, beta, and delta transactivated promoter activity and increased native FLAP mRNA accumulation. Mutation of both C/EBP sites essentially abolished promoter induction by C/EBP overexpression. Tumor necrosis factor (TNF) alpha induced FLAP mRNA expression, FLAP promoter activity, and C/EBP alpha, delta, and epsilon binding to the proximal and distal promoter consensus sites. Chromatin immunoprecipitation assays demonstrated that C/EBP alpha, delta, and epsilon bound to this region of the 5'-untranslated region, whereas C/EBP beta does not bind even under conditions of overexpression and stimulation. We conclude that the FLAP gene is transactivated by members of the C/EBP family of transcription factors in inflammatory cells and that these factors play an important role in FLAP gene induction by TNFalpha.

Leukotrienes formed by the action of 5-lipoxygenase on arachidonic acid are a group of endogenous compounds active in hypersensitivity reactions and inflammation. In this report the formation of LTB4 from LTA4 was measured by incubating lung microsomes from normal and exercised rats to determine whether LTB4 may have a role in the mediation of exercise-induced oxidant stress. Exhaustive exercise in the form of swimming results in the enhanced production of LTB4 in lung microsomes. Further, free radicals measured by ESR spectroscopy were also significantly increased in lung tissue from exercised rats. These results suggest a role for LTB4 in the mediation of lung tissue damage during exercise-induced oxidative stress.

For the last several decades, bioinorganic chemists have synthesized novel mononuclear, binuclear, and more recently polynuclear ligand systems in an effort to mimic the coordination state of iron and copper in redox metalloproteins, especially those involved in the binding and activation of dioxygen. The favored utilization by nature of the histi-dine imidazole moiety for providing a neutral and relatively “soft” ligation of metal ions has resulted in the common use of sp2 nitrogen (in particular pyridine and related heterocycles as well as imines) in addition to sp3 amino nitrogen in the design of biomimetic ligands. Although sp2 imino nitrogen is relatively resistant to oxidation, sp3 amino nitrogen is, in general, subject to oxidation at the potentials generated in most instances of iron- and copper-02 interaction. Ligand dehydrogenation has been observed in some cases, usually as an unwanted side-reaction (eq 1),1 but such instances provide important information needed for the rational design of robust ligands as well as about the nature and mechanism of metal ion-mediated amine oxidation.

Strenuous physical exercise in the form of swimming in female albino rats increased the oxidative reactions, probably leading to the generation of oxy-free radicals in the lung tissue. Free radical-mediated lipid peroxidation measured in the form of lipid peroxides increased in the pulmonary tissue in response to exhaustive exercise, indicating such a possibility. Dietary supplementation of vitamin E (Vit.E) and selenium (Se) for a period of 12 weeks reduced the oxidative reactions and the ensuing lipid peroxidation in the pulmonary tissue. Physical exercise in control animals induced the activity of superoxide dismutase (SOD), the superoxide anion radical (O2-.) quencher. However, the SOD levels in nutrient-fed animals at rest and after exercise remained well below the control levels, indicating the decreased generation of oxy-free radicals in them. Similarly, selenium-dependent glutathione peroxidase (Se-GSH Px), the enzyme involved in the reduction of organic and inorganic peroxides, and glutathione S- transferase (GST), the multifunctional protein involved in the detoxification of a number of xenobiotics, were increased in response to exercise in control animals, but were significantly decreased in nutrient-fed animals upon exercise. The induction of GST seems to be more towards the peroxidase activity of GST, i.e., non-selenium glutathione peroxidase (Non-Se-GSH Px), which is primarily involved in the reduction of endoperoxides. The studies thus indicate the induction of oxidative stress in the pulmonary tissue upon exhaustive physical exercise and the effectiveness of vit.E and Se independently and more so in combination in combating the exercise-induced oxidant stress.

The synthesis and characterisation of ruthenium(II) complexes with 2-amidobenzimidazoles are reported. The complexes RuCl2(DMSO)4 and RuCl2(PPh3) react with 2-(acetamido)benzimidazole (AB) and 2-(benzamido)benzimidazole (BB) it acetone to give products of the type [Ru(L)2(N−O)2]Cl2 [L=DMSO, PPh3, N−O=AB, BB). The displacement reactions are faster in the case of methyl (AB) than phenyl (BB) substituted ligands. The ligands are bifunctional chelating agents coordinating through the tertiary nitrogen of benzimidazole ring and amide oxygen. The complexes are characterised based on their elemental analysis, conductivity data, infrared,1H and31P nmr spectra. Acis-geometry is proposed for all the complexes reported.

Reactions of RuCl 2 (DMSO) 4 with some of the biologically active polydentate ligands containing an amide group yielded a number of stable complexes, effecting partial or complete displacement of DMSO groups from the complex, depending on the type of ligand. The interaction of anionic bidentate ligands with RuCl 2 (DMSO) 4 yielded neutral complexes of the type Ru(DMSO) 2 (LL) 2 (LL = AAB,BAB, MA, ACB, PACB and NACB) displacing only two DMSO groups and the two chlorides. With uninegative terdentate ligands, all the DMSO groups were displaced and complexes of the formula Ru(L) 2 (L = ABAB, APACB and ABB) were obtained. A complex RuCl 2 (DMSO) 2 (ABA) 2 was also obtained by a similar method. The infrared and proton NMR spectra of these complexes have been found to be useful in identifying and characterising them.

A number of ruthenium(II) complexes of some polydentate ON, OO and ONO donors in the form of 2-methyl-3-substituted (3 H )-quinazolin-4-ones have been synthesized and studied. The reaction between RuCl 2 (DMSO) 4 and the uninegative bidentate ligands yielded complexes of the type Ru(DMSO) 2 (OO) 2 (OO = MHQ, PHQ, MHEQ, MHPQ or MCMQ), displacing only two DMSO groups along with chlorides, whereas the neutral bidentate ligands gave RuCl 2 (ON) 2 (ON = MAQ, PAQ, MANQ, PANQ, MAAQ, MAPQ, MPQ or PPQ), displacing all the DMSO groups. A uninegative terdentate ligand (MHAQ) with ONO donors, however, yielded a bis chelate of ruthenium(II).

The interaction of tri-p-tolylarsine with ruthenium trichloride trihydrate in acidified methanol under reflux gave a complex, RuCl 3 (AsTol P 3 ) 2 (MeOH) ( 1 ). Complex 1 has been employed as a useful starting material for the preparation of other ruthenium(II) and (III) complexes. On treating complex 1 with excess of nitriles, complexes of the type RuCl 3 (AsTol P 3 ) 2 (RCN) (R = CH 3 , C 6 H 5 , C 6 H 5 CH 2 ) were obtained. Complex 1 gave RuCl 3 (AsTol P 3 (Py) 2 and RuCl 2 (Py) 4 respectively, on reaction with excess of pyridine in n-hexane and dichloromethane. The reactions of 2,2′-bipyridine and 1,10-phenanthroline (NN) with complex 1 in dichloromethane resulted in the formation of RuCl 3 (AsTol P 3 )(NN). A five coordinate complex RuCl 3 (AsTol P 3 ) 2 was isolated from dichloromethane, chloroform or benzene solutions of complex 1 . The dissolution of complex 1 in acetone gave a stable adduct RuCl 3 (AsTol P 3 ) 2 (Me 2 CO).

A new neutral ruthenium(II) complex of dihydro-bis(1-pyrazolyl) borate is synthesised by the reaction of RuCl2(PPh3)3 with the ligand in methanol and is characterised on the basis ofir and31P{1H}nmr spectra.

A metathetical reaction conducted between RuCl3(AsPh3)2(MeOH) and a large excess of NH4I afforded a high-spin pentacoordinate complex, RuI3(AsPh3)2 (high-spin /paramagnetic/triphenylarsine/iodide/ruthenium(III) complex).

A binuclear μ-peroxo ruthenium(III) complex of the composition [Cl2(AsPh3)3RuO2Ru(AsPh3)3Cl2]Cl2 is reported.

The reaction of ruthenium(III) perchlorate with some polytertiary phosphines or arsines has been investigated. With bidentate ligands in ethanol cationic complexes of the type [Ru(L–L)3(ClO4)]ClO4(L–L = Ph2PCH2PPh2, Ph2PCH2CH2PPh2, Ph2AsCH2CH2AsPh2, or Ph2AsCH2CH2PPh2) are obtained. With terdentate ligands the complexes obtained are of the type [RuL2(ClO4)][ClO4]2[L = NH(CH2CH2PPh2)2 or NH(CH2CH2AsPh2)2]. The reaction of the complex [RuCl3(AsPh3)2(MeOH)] with AsPh3 and PPh3 in the presence of an excess of NaClO4 in methanol gave [Ru(AsPh3)4(ClO4)2]ClO4 and [Ru(AsPh3)(PPh3)3(ClO4)2]ClO4 respectively. With terdentate ligands [RuCl3(AsPh3)2(MeOH)] afforded mixed-ligand cationic complexes of the type [Ru(AsPh3)2L(ClO4)][ClO4]2[L = NH(CH2CH2PPh2)2 or NH(CH2C2AsPh2)2]. Perchlorate co-ordination is discussed in terms of the i.r. spectra of complexes, and structures are proposed based on the 1H, 31P, and 14N n.m.r. spectra.