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1.
Am J Cancer Res ; 14(6): 2755-2769, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005687

RESUMO

As numerous countries around the world have entered an aging society currently, understanding the impact of aging on human health becomes critically important. Notably, aging is associated with increased prevalence of age-related diseases, with the lungs being particularly susceptible. Aging contributes to a decline in lung function, including respiratory disorders, inflammation, and oxidative stress. Therefore, it is a very important to identify and develop active substances that can mitigate lung cell aging. In current study, we evaluated the impact of Taraxasterol on lung cell senescence, showing that Taraxasterol can alleviate lung cell senescence, as evidenced by reductions in senescence-related marker molecules, including p16 and p21. Additionally, Taraxasterol was found to ameliorate inflammation and oxidative stress in lung cells. Further mechanistic studies indicated that Taraxasterol exerts anti-aging effects through the PGC1α/NRF1 signaling pathway in lung cell models. Since aging is also closely related to lung cancer, we also explored the potential anti-tumor effect of taraxasterol. Utilizing non-small cell lung cancer cells (NSCLC) as a model, we systematically study the anti-tumor effect of Taraxasterol both in vivo and in vitro. Our findings suggest that Taraxasterol exhibited anti-cancer effect through EGFR-mediated signaling. Taken together, Taraxasterol shows dual biological activities, offering promising anti-aging and anti-lung cancer benefits.

2.
Dalton Trans ; (18): 2487-94, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18461205

RESUMO

A new fluorenyl-substituted dioxotetraamine salicylaldehyde Schiff-base ligand (L1) has been synthesized by the non-template 1 + 2 condensation of ligand 6-(9-fluorenyl)-1,4,8,11-tetraazaundecane-5,7-dione (L) with salicylaldehyde. From reduction of L1 with an excess of NaBH4, a ditopic dioxotetraamine ligand (L2) has been obtained. The copper(II) complex of L1 has been synthesized and its properties were examined by ES-MS and variable-temperature magnetic susceptibility as well as its crystal structure being determined. Detailed studies have been made on solution chemistry of Cu(II) complex of L2 by pH-potentiometric and fluorometric titration.


Assuntos
Aminas/síntese química , Cobre/química , Fluorenos/química , Magnetismo , Oxigênio/química , Aminas/química , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Ligantes , Modelos Moleculares , Estrutura Molecular , Soluções , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Titulometria
3.
Inorg Chem ; 45(3): 1124-9, 2006 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-16441122

RESUMO

This paper reports the syntheses and crystal structures of a manganese and a uranyl phosphonate based on 1,4,7-triazacyclononane-1,4,7-triyl-tris(methylenephosphonic acid), namely, Mn3{C9N3H18(PO3)3}(H2O)6 x 1.5 H2O (1) and UO2{C9N3H19(PO3H)3} x H2O (2). Compound 1 shows a unique layer structure where the hydrophobic triazacyclononane moieties all reside on one side of the inorganic backbone of the manganese phosphonate layer while the hydrophilic coordinated water molecules reside on the other side. In compound 2, the triazacyclononane moieties are immobilized on the inorganic backbone of the uranyl phosphonate chains. The magnetic properties of compound 1 and the ion exchange properties of compound 2 have been studied.

4.
Dalton Trans ; (15): 2329-35, 2004 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-15278126

RESUMO

Two copper(II) complexes [CuL(1)Cl]ClO(4) and [CuL(2)MeCN](ClO(4))(2)xH(2)O were synthesized (L(1)= 1-(benzimidazole-2-ylmethyl)-1,4,7-triazacyclononane, L(2)= 1,4-bis(benzimidazole-2-ylmethyl)-1,4,7-triazacyclonone). The benzimidazole groups were N-substituents of tacn, and the complexes are more stable than their parents. They are able to catalyse the dismutation of superoxide anion in aqueous solutions at physiological pH and in bovine serum albumin solution (0.5 mg ml(-1)). X-ray structure analysis and EPR and electronic spectra show that the structure of complex is more similar to the Cu(II) centre of Cu(2)Zn(2)SOD than that. Comparing with other Cu(II) complexes, the complex possesses both high SOD activity and highly thermodynamic stability.


Assuntos
Benzimidazóis/química , Materiais Biomiméticos/química , Cobre/química , Compostos Heterocíclicos/química , Mimetismo Molecular , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Materiais Biomiméticos/metabolismo , Catálise , Cristalografia por Raios X , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Estrutura Molecular , Soroalbumina Bovina/química , Soluções/química , Superóxidos/metabolismo , Termodinâmica , Titulometria
5.
Dalton Trans ; (7): 1104-11, 2004 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-15252689

RESUMO

Two novel silver(I) cryptates are reported in this paper. [Ag(2)(L(1)O)](ClO(4))(2).H(2)O and [Ag(2)L(1)](ClO(4))(2).1.5H(2)O were synthesized by the condensation of tris (3-aminopropyl) amine with m-phthalaldehyde in the presence of silver(i) ion, under aerobic and anaerobic conditions, respectively. (The ligand L(1)O represents the oxygen insertion product of L(1).) Cryptates 1, 2 and their hydrogenated ligand H(12)(L(1)O) 3 and H(12)L(1) 4 (obtained by reduction of the cryptates) were investigated by electrospray mass spectroscopy (ES-MS). 1 and 2 were also decomposed by HCl treatment and their products were separated and identified by HPLC and ES-MS. Our experiments show that cryptate 2 is able to activate dioxygen that results in quantitative aliphatic hydroxylation of L(1) on one of its HC=N bonds. Crystal structure analysis shows an interesting difference between 1 and 2 in that 1 is an oxygenated and 2 is a non-oxygenated cryptate. Up to date, ligand hydroxylation has not been achieved in silver(I) complex-O(2) systems.

6.
Bioelectrochemistry ; 64(1): 33-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15219244

RESUMO

The electrochemical behavior of Cu(2)Zn(2)SOD on mercury electrodes was studied by controlled potential electrolysis. By comparison of UV, Raman spectra and activity of Cu(2)Zn(2)SOD before electrochemical reduction and after re-oxidation, it is proved that the conformation and activity are not changed.


Assuntos
Eletrólise/métodos , Eritrócitos/enzimologia , Mercúrio/química , Análise Espectral Raman/métodos , Superóxido Dismutase/metabolismo , Animais , Bovinos , Cobre/química , Eletrodos , Oxirredução , Potenciometria , Superóxido Dismutase/química , Zinco/química
7.
Bioelectrochemistry ; 58(2): 197-201, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12414327

RESUMO

The electrochemistry of Co(2)Co(2)SOD and Cu(2)Co(2)SOD on a pyrolytic graphite electrode (PGE) without using mediators was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The reversible and quasi-reversible voltammetric responses were observed for Co(2)Co(2)SOD and Cu(2)Co(2)SOD, respectively. Their formal redox potentials and electron numbers involved in electrode reactions were obtained, and are in agreement with those by spectroelectrochemistry (SEC).


Assuntos
Cobalto/química , Cobre/química , Superóxido Dismutase/química , Carbono , Eletroquímica , Eletrodos , Transporte de Elétrons , Grafite , Oxirredução
8.
Chemistry ; 8(17): 3984-90, 2002 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-12360939

RESUMO

Four heterodinuclear cryptates [EuML(dmf)](ClO(4))(2) (M=Ca, Cd, Ni, Zn) were synthesized by a two-step method (L denotes deprotonated anionic cryptand synthesized by condensation of tris(2-aminoethyl)amine with 2,6-diformyl-4-chlorophenol). The ES-MS spectra of the four cryptates and the crystal structure of [EuNiL(dmf)](ClO(4))(2) x MeCN confirm that a strict dinuclear Eu(III)-M(II) entity exits in the cryptates. The cyclic voltammetry and luminescence spectral investigations indicate that the introduction of second metal ions into the mononuclear Eu(III) cryptate result in a negative shift of the redox potential of Eu(III) and a change in luminescence intensity of Eu(III). The cryptate [EuML(dmf)](ClO(4))(2) was shown to quench the emission of Eu(III) when M=Ni and to enhance the emission of Eu(III) when M=Ca, Cd, and Zn in the sequence: mononuclear

Assuntos
Európio/química , Medições Luminescentes , Metais/química , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
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