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1.
Cell Immunol ; 362: 104304, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33610024

RESUMO

HIV-infected individuals on combined antiretroviral therapy (ART) with virologic suppression exhibit sustained immune dysfunction. Our recent work has highlighted that monocytic myeloid derived suppressor cells (M-MDSC) are elevated in these individuals and suppress immune responses. Factors responsible for M-MDSC expansion in vivo are unknown. Here we compared circulating frequency of M-MDSC in HIV-infected persons from the US and India where HIV subtype-B or -C predominate, respectively. We further investigated soluble mediators of residual immune activation in two cohorts and determined their correlation with M-MDSC expansion. Our findings show that M-MDSC are elevated and correlate with plasma levels of IL-6 in both cohorts. Chemokines CXCL10, CCL4 and CXCL8 were also elevated in HIV-infected individuals, but did not correlate with M-MDSC. These findings support that IL-6 is important in M-MDSC expansion which is independent of HIV subtype.


Assuntos
Infecções por HIV/imunologia , Interleucina-6/imunologia , Células Supressoras Mieloides/imunologia , Adulto , Antirretrovirais/farmacologia , Células Cultivadas , Progressão da Doença , Feminino , Microbioma Gastrointestinal/fisiologia , Infecções por HIV/metabolismo , HIV-1/imunologia , HIV-1/patogenicidade , Humanos , Índia/epidemiologia , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Células Supressoras Mieloides/metabolismo , Estados Unidos/epidemiologia
2.
J Family Med Prim Care ; 9(7): 3613-3618, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33102338

RESUMO

BACKGROUND: Iron-deficiency anemia is considered to be a major health problem in India. This can complicate a normal pregnancy resulting in poor maternal and fetal outcomes. Iron-folic-acid (IFA) supplementation to antenatal and postnatal mothers given through the National Health Mission (NHM) serves as a major tool to combat this problem. AIM: This study aimed to assess compliance to IFA supplement and associated factors among antenatal mothers in a district of West Bengal, India. METHODS: A cross-sectional observational study was conducted among 208 pregnant mothers attending different subcenters, using multistage sampling technique. Data were collected on their demographic, obstetric profile, compliance to IFA tablets, and knowledge on various health care-related factors through direct interviews. Data were analyzed using SPSS 22.0 (licensed) considering the confidence interval to be 95%. RESULTS: Compliance rate was 81.74%. The most common cause of noncompliance was forgetfulness (73.7%). On multivariate regression analysis, age, history of deworming, and education became the significant predictors for noncompliance to IFA. CONCLUSIONS: Compliance to IFA supplementation was better than the national average, although deworming and education can lead to a better outcome. Health workers played a pivotal role for the success of this national program.

3.
Inorg Chem ; 56(9): 4966-4977, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28426213

RESUMO

In this work, ortho-C-N bond fusion reactions of aniline are followed by the use of two different ruthenium mediators. Reaction of aniline with [RuIII(terpy)Cl3] (terpy = 2,2':6',2″-terpyridine) resulted in a trans bis-aniline ruthenium(II) complex [1]+ which upon oxidation with H2O2 produced compound [2]+ of a bidentate ligand, N-phenyl-1,2-benzoquinonediimine, due to an oxidative ortho-C-N bond fusion reaction. Complex [1]+ and aniline (neat) at 185 °C produced a bis-chelated ruthenium complex (3). A previously reported complex [RuII(N-phenyl-1,2-benzoquinonediimine)(aniline)2(Cl)2] (5) undergoes similar oxidation by air at 185 °C to produce complex [3]. A separate chemical reaction between aniline and strongly oxidizing tetra-n-propylammonium perruthenate [(n-pr)4N]+[RuO4]- in air produced a ruthenium complex [4] of a N4-tetraamidophenylmacrocycle ligand via multiple ortho-C-N bond fusion reaction. Notably, the yield of this product is low (5%) at 100 °C but increases to 25% in refluxing aniline. All these complexes are characterized fully by their physicochemical characterizations and X-ray structure determination. From their structural parameters and other spectroscopic studies, complex [2]+ is assigned as [RuII(terpy)(N-phenyl-1,2-benzoquinonediimine)(Cl)]+ whereas complex [4] is described as a ruthenium(VI) complex comprised of a reduced deprotonated N-phenyl-1,2-diamidobenzene and N4-tetraamidophenylmacrocyclic ligand. Complex [2]+ exhibits one reversible oxidation at 1.32 V and one reversible reduction at -0.75 V vs Ag/AgCl reference electrode. EPR of the electrogenerated complexes has revealed that the oxidized complex is a ruthenium(III) complex with an axial EPR spectrum at gav= 2.06. The reduced complex [2], on the other hand, shows a single-line EPR signal at gav= 1.998. In contrast, complex [4] shows two successive one-electron oxidation waves at 0.5 and 0.8 V and an irreversible reduction wave at -0.9 V. EPR studies of the oxidized complexes [4]+ and [4]2+ reveal that oxidations are ligand centered. DFT calculations were employed to elucidate the electronic structures as well as the redox processes associated with the above complexes. Aerial ortho-C-N bond fusion reactions of aniline using two different mediators, viz. [RuIII(terpy)Cl3] and [(n-pr)4N]+[RuO4]-, have been followed. It is found that in the case of oxidizable Ru(III) mediator complex, C-N bond fusion is limited only to dimerization reaction whereas the high-valent Ru(VII) salt mediates multiple C-N bond fusion reactions leading to the formation of a novel tetradentate N4-tetraamidophenylmacrocyclic ligand. Valence ambiguity in the complexes of the resultant redox-active ligands is scrutinized.

4.
Inorg Chem ; 53(9): 4678-86, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24742026

RESUMO

The isolation and complete characterization of a new bis-azoaromatic ligand, 2,6-bis(phenylazo)pyridine (L), are described, and its coordination to iron(II) is reported. A pseudo-trigonal-bipyramidal mixed-ligand complex of iron(II), FeLCl2 (1), and a homoleptic octahedral iron complex, mer-[Fe(L)2]ClO4 [2]ClO4, have been synthesized from L and FeCl2 or hydrated Fe(ClO4)2, respectively, in boiling methanol. Determination of the X-ray crystallographic structure together with magnetic data (≈ 5.06 µB) and Mössbauer analysis of 1 established a high-spin Fe(II) complex ligated by one neutral 2,6-bis(phenylazo)pyridine ligand. The X-ray crystallographic structure (showing dN-N > 1.30 Å), Mössbauer data, and magnetic susceptibility measurements (≈ 1.65 µB) as well as a nearly isotropic EPR signal with only a small metal contribution at g = 1.968, on the other hand, suggest a low-spin Fe(II) complex with a one-electron-reduced radical ligand coordination in [2]ClO4. The ligand and the metal complexes have well-behaved redox properties, with the ligand(s) functioning as the redox-active site(s) responsible for redox events. The uncoordinated ligand, L, displays a reversible one-electron wave at -1.07 V and a quasi-reversible wave at -1.39 V. The partially reduced ligand L(•-) shows a single-line EPR spectrum at g = 2.001, signifying that L(•-) is a free radical. While complex 1 shows a reversible reduction at -0.08 V and an irreversible cathodic response at -0.98 V, the bis-chelate [2]ClO4 undergoes a reversible one-electron oxidation at 0.54 V and three successive reversible one-electron reductions at -0.18, -0.88, and -1.2 V, all occurring at the ligands without affecting the metal ion oxidation state. The electronic structures of the parent monocationic complex [2](+) and its oxidized and reduced forms, generated by exhaustive electrolyses, have been characterized by using a host of spectroscopic techniques and density functional theory (DFT). It is found that the 2,6-bis(phenylazo)pyridine ligand (L) is truly redox noninnocent and is capable of coordinating transition-metal centers in its neutral ([L](0)), monoanionic monoradical ([L(•)](-)), and dianionic diradical ([L(••)](2-)) forms.

5.
Chemistry ; 20(10): 2712-7, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24482022

RESUMO

Three examples of unusual double aromatic CH bond activation associated with insertion of etheral oxygen atom to phenazine architecture in Ru(III) complexes are reported. The chemical transformations have led to the formation of new Ru(IV) complexes with angular pentacyclo heterocyclic ligands. A mechanistic investigation indicates that the overall process is a combination of successive steps involving air (O2 ) and H2 O.

6.
Inorg Chem ; 52(24): 14040-9, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24261923

RESUMO

A series of cobalt complexes of ligands based on the 2-(arylazo)pyridine architecture have been synthesized, and the precise structure and stoichiometry of the complexes depend critically on the identity of substituents in the 2, 4, and 6 positions of the phenyl ring. The 2-(arylazo)pyridine motif can support either Co(II) complexes with neutral ligands, Co(II)Cl2(L(a))2 (1), Co(II)Cl2(L(c))2 (3), [Co(II)Cl(L(b))2]2(PF6)2 (5[PF6]2), or Co(III) complexes of reduced 2-(arylazo)pyridine ligand radical anions, L(•-), Co(III)Cl(L(b•-))2 (2), Co(III)Cl(L(c•-))2 (4), and Co(III)Me(L(b•-))2 (6). All three members of the latter class are based on approximately trigonal-bipyramidal CoX(L(•-))2 architectures [L = 2-(arylazo)pyridine] with two azo nitrogen atoms and the X ligand (X = Cl or Me) in the equatorial plane and two pyridine nitrogen atoms occupying axial positions. Density functional theory suggests that the electronic structure of the Co(III) complexes is also dependent on the identity of X: the strong σ-donor methyl gives a low-spin (S = 0) configuration, while the σ/π-donor chloro gives an intermediate-spin (S = 1) local configuration. In certain cases, one-electron reduction of the Co(II)X2L2 complex leads to the formation of Co(III)X(L(•-))2; i.e., reduction of one ligand induces a further one-electron oxidation of the metal center with concomitant reduction of the second ligand.

7.
J Org Chem ; 77(22): 10249-59, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23078049

RESUMO

This work reports the results of our investigation on the aerial oxidation of aromatic amines that are promoted by protic acid. While primary aromatic amines produce substituted phenazines as major products, N-phenyl-o-phenylenediamine produces polycyclic aromatic heterocycles like azaacene and secondary and tertiary amines give exclusively the dyes containing a triphenylmethane moiety. Isolation of the compounds and the effects of substitutions on the aromatic rings have been investigated. In this context, plausible reaction steps that are involved have been discussed. Single-crystal X-ray structure analyses of the representative compounds are solved to authenticate their formation. In almost every case, a high degree of delocalization of electron was noted. The compounds have been characterized thoroughly and show rich spectral properties. For example, the phenazine molecules exhibited absorption peaks between 475 and 605 nm because of the charge-transfer transition from the amine and tricyclopyrazine moiety. Their acidochromic and solvatochromic behaviors, which are supported by theoretical calculations, are investigated. The polycyclic azacene molecule exhibits strong absorption in the visible region and fluoresces with high quantum yield. The phenazine dyes undergo a quasi-reversible reduction at a low cathodic potential that varies linearly as a function of Hammett's constant.

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