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1.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769202

RESUMO

Treatment of neoplastic diseases in companion animals is one of the most important problems of modern veterinary medicine. Given the growing interest in substances of natural origin as potential anti-cancer drugs, our goal was to examine the effectiveness of benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, against canine lymphoma and leukemia. These are the one of the most common canine cancer types, and chemotherapy is the only treatment option. The study involved established cell lines originating from various hematopoietic malignancies: CLBL-1, GL-1, CLB70 and CNK-89, immortalized noncancerous cell lines: MDCK and NIH-3T3 and canine peripheral blood mononuclear cells (PBMCs). The cytotoxic activity of BITC, apoptosis induction, caspase activity and ROS generation were evaluated by flow cytometry. H2AX phosphorylation was assessed by western blot. The study showed that the compound was especially active against B lymphocyte-derived malignant cells. Their death resulted from caspase-dependent apoptosis. BITC induced ROS accumulation, and glutathione precursor N-acetyl-l-cysteine reversed the effect of the compound, thus proving the role of oxidative stress in BITC activity. In addition, exposure to the compound induced DNA damage in the tested cells. This is the first study that provides information on the activity of BITC in canine hematopoietic malignancies and suggests that the compound may be particularly useful in B-cell neoplasms treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Doenças do Cão/tratamento farmacológico , Isotiocianatos/farmacologia , Leucemia/veterinária , Linfoma/veterinária , Animais , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Doenças do Cão/genética , Doenças do Cão/metabolismo , Cães/genética , Cães/metabolismo , Isotiocianatos/química , Leucemia/tratamento farmacológico , Leucemia/genética , Leucemia/metabolismo , Linfoma/tratamento farmacológico , Linfoma/genética , Linfoma/metabolismo , Células Madin Darby de Rim Canino , Camundongos , Células NIH 3T3 , Espécies Reativas de Oxigênio/metabolismo , Verduras/química
2.
Analyst ; 144(13): 3967-3971, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31140474

RESUMO

An OFF-ON detection method for Cu2+ was developed at the AgAu bimetallic nanoparticle decorated nitrogen-doped graphene (AgAu-NG) nanocomposite modified electrode. The measurement was based on the copper-catalyzed oxidation of cysteamine (Cys) to regulate the oxidation peak current of Ag. In the absence of Cu2+, Cys can bind to the surface of AgAu-NG via the Ag-S or Au-S bond, thus leading to an obvious decrease of the oxidation peak current of Ag. However, in the presence of Cu2+, Cu2+ can greatly catalyze the oxidation of Cys by dissolved O2 to form cystamine, which would fall off the surface of AgAu-NG nanocomposites, leading to the partial recovery of the oxidation peak current of Ag. With the increase in the concentration of Cu2+, the oxidation peak current of Ag in the presence of Cys increases accordingly. So, the concentration of Cu2+ can be measured. By using the optimum conditions, this method can detect Cu2+ concentrations down to 0.3 nM (S/N = 3) with a linear response range of 1 nM-1 mM. Furthermore, this method was applied to determine Cu2+ concentrations in river water samples and showed excellent analytical performance.

3.
Nanotechnology ; 30(28): 285502, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30884476

RESUMO

In this paper, a novel electrochemical sensor based on Au nanoparticles/8-aminoquinoline functionalized graphene oxide (AuNPs/GAQ) nanocomposite was developed and tested for the first time for detection of paraquat (PQ). The morphology and composition of AuNPs/GAQ nanocomposite were characterized by various techniques, including transmission electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and x-ray photoelectron spectroscopy. Cyclic voltammetry and differential pulse voltammetry were utilized to investigate the electrochemical performances of AuNPs/GAQ nanocomposite modified glassy carbon electrode. The obtained modified electrode exhibited excellent electrocatalytic activity towards detection of PQ. Under the optimized conditions, the proposed sensor showed low detection limit (6 nM, S/N = 3), wide linear range (0.02-24 µM), high selectivity and good stability. In addition, it was successfully applied for detection of PQ in natural water samples with satisfactory results.

4.
Mikrochim Acta ; 186(5): 321, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049702

RESUMO

A glassy carbon electrode (GCE) was modified with a nanocomposite prepared from nitrogen-doped reduced graphene oxide (N-rGO) and single walled carbon nanotubes (SWCNTs), and then loaded with platinum nanoparticles (Pt NPs) to obtain a voltammetric sensor for daunorubicin (DNR). Reductive doping of GO and the crystallization of the Pt NPs were carried out in a one-step hydrothermal process. The modified electrode was characterized by cyclic voltammetry and differential pulse voltammetry. It exhibited high sensitivity compared with unmodified electrode. Some experimental parameters which affected sensor response were optimized. Under optimum conditions and at a working voltage of typically -0.56 V (vs. Ag/AgCl), the sensor has a low detection limit (3 ng mL-1), a wide linear range (0.01-6 µg mL-1) and good long-term stability. The method was successfully applied to the sensitive and rapid determination of DNR in spiked human serum samples. Graphical abstract Platinum nanoparticles were loaded onto a nanocomposite prepared from nitrogen decorated reduced graphene oxide and single-walled carbon nanotubes (N-rGO-SWCNTs-Pt) and then used for electrochemical determination of daunorubicin (DNR).


Assuntos
Antineoplásicos/análise , Daunorrubicina/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotubos de Carbono/química , Platina/química , Antineoplásicos/sangue , Técnicas Biossensoriais/métodos , Daunorrubicina/sangue , Eletrodos , Humanos , Limite de Detecção , Nitrogênio/química , Oxirredução
5.
Mikrochim Acta ; 186(3): 177, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771082

RESUMO

An electrochemical sensor is described for the simultaneous determination of the pollutants catechol (CC) and hydroquinone (HQ). A glassy carbon electrode (GCE) was modified with reduced graphene oxide, Fe3O4 and gold nanoparticles and then showed a pair of well-defined voltammetric peaks for CC and HQ. Its oxidation peak potentials (located at 0.21 and 0.10 V vs. Ag/AgCl) are well separated, and this makes it suitable for simultaneous determination of the two isomers. Under optimal conditions, the oxidation peak currents of CC and HQ increase linearly in the 0.05-550 µM and 0.1-500 µM concentration ranges, even in the presence of 0.1 mM of the respective other isomer. The detection limits are 0.02 and 0.17 µM (at S/N = 3), respectively. The modified GCE exhibits good selectivity and recovery when applied for the analysis of spiked wastewater. Graphical abstract Ternary hybrid nanomaterials of rGO-Fe3O4-Au was developed for simultaneous electrochemical determination of catechol (CC) and hydroquinone (HQ).

6.
Molecules ; 22(9)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28858253

RESUMO

Nanotechnology has become more and more potentially used in diagnosis or treatment of diseases. Advances in nanotechnology have led to new and improved nanomaterials in biomedical applications. Common nanomaterials applicable in biomedical applications include liposomes, polymeric micelles, graphene, carbon nanotubes, quantum dots, ferroferric oxide nanoparticles, gold nanoparticles (Au NPs), and so on. Among them, Au NPs have been considered as the most interesting nanomaterial because of its unique optical, electronic, sensing and biochemical properties. Au NPs have been potentially applied for medical imaging, drug delivery, and tumor therapy in the early detection, diagnosis, and treatment of diseases. This review focuses on some recent advances in the use of Au NPs as drug carriers for the intracellular delivery of therapeutics and as molecular nanoprobes for the detection and monitoring of target molecules.


Assuntos
Portadores de Fármacos/administração & dosagem , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Animais , Portadores de Fármacos/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Sondas Moleculares/administração & dosagem , Sondas Moleculares/química , Imagem Óptica , Coloração e Rotulagem
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(12): 1487-91, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25632751

RESUMO

OBJECTIVE: To study the effect of Bushen Tongdu Capsule (BTC) on RANK/RANKL/ OPG pathway of collagen induced arthritis (CIA) rats, thereby laying theoretic evidence for treating rheumatic arthritis (RA) by Chinese medicine. METHODS: RA model was induced by CIA. Totally 42 rats were randomly divided into six groups, i.e., the normal control group, the model group, the low dose BTC (BSL) group, the medium dose BTC (BSM) group, the high dose BTC (BSH) group, and the Tripterygium Glycosides (TG) group, 7 in each group. BTC at the daily dose of 120, 240, and 480 mg/kg was given by gastrogavage to rats in the BSL, BSM, and BSH group respectively from the 13th day of modeling. TG at the daily dose of 24 mg/kg was given by gastrogavage to rats in the TG group. All medication was given once daily, 2 mL each time. Two mL normal saline was administered to rats in the normal control group and the model group. All medication lasted for 18 days. Samples were taken at day 31. The TRAP section of the ankle joint was fixed in 10% formalin for TRAP stain. Serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), and macrophage colony-stimulating factor (M-CSF) were detected using ELISA. RESULTS: Compared with the normal control group, positive reactions of pathological ankle joint section, inflammation, and osteoclasia degree were significantly improved in the model group, serum levels of RANKL and M-CSF were up-regulated, levels of OPG and OPG/RANKL were significantly lowered (all P < 0.01). Compared with the model group, positive reactions of pathological ankle joint section, inflammation, and osteoclasia degree also significantly decreased in the BSH group and the TG group (all P < 0.01). RANKL and M-CSF were significantly down-regulated in each medicated group, while levels of OPG and OPG/RANKL were significantly up-regulated (all P < 0.01). Compared with the TG group, M-CSF was lower, but levels of OPG and OPG/RANKL were significantly up-regulated in the normal control group (all P < 0.01). RANKL and M-CSF were significantly up-regulated, while levels of OPG and OPG/RANKL were significantly down-regulated in the model group and each BS group (all P < 0.01). CONCLUSION: BTC could relieve bone damage of CIA rats possibly through regulating and controlling osteoclasts.


Assuntos
Artrite Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Animais , Inflamação , Fator Estimulador de Colônias de Macrófagos/metabolismo , Osteoclastos , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Ratos , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Tripterygium
8.
Dalton Trans ; 51(10): 3970-3976, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35171175

RESUMO

Two transition metal complexes {[Co2(bpda)4(H2O)2]·4H2O}n(Co-1) and {[Ni(bpda)2(H2O)2]·2H2O}(Ni-2) (H2bpda = 2,2'-bipyridine-4,4'-dicarboxylic acid) have been synthesized by a hydrothermal method and characterized. These two compounds can be explored as stable electrocatalysts in the hydrogen evolution reaction (HER) using two important parameters: the overpotential and Tafel slope (TS). Electrochemical studies suggest that the reaction kinetics of a Co-1 catalyst is more favorable than that of a Ni-2 catalyst. Co-1 exhibits better HER performance with an overpotential of 182 mV at a current density of 10 mA cm-2, a small TS of 87.21 mV dec-1 and superior long-term durability (of up to 3000 cycles). Structural analysis shows that its catalytic activity is improved due to the two mixed valence cobalt ions and the pore structure formed by hydrogen bonds in Co-1, which is different from that of Ni-2. In addition, the mechanism of the HER is also explained theoretically by DFT molecular orbital and free energy calculations in this article.

9.
RSC Adv ; 10(11): 6192-6199, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35496023

RESUMO

Three lanthanide compounds have been synthesized, namely, {[Dy2(bpda)3(H2O)3]4·2H2O}(Dy-1), {[Sm(bpda)2·(H2O)]·H2O} n (Sm-2) and {[Tb2(bpda)3(H2O)3]4·2H2O} (Tb-3) (H2bpda = 2,2'-bipyridine-6,6'-dicarboxylic acid). Their structures were determined by single crystal X-ray diffraction and characterized by elemental analysis, infrared spectroscopy and thermogravimetric analysis. Dy-1 and Tb-3 are isostructural with a conjugate bimolecular four-nuclear cluster structure constructed with intramolecular hydrogen bonds and they form a 3D supramolecular structure with intermolecular hydrogen bonding. Sm-2 is a one-dimensional chain structure and is further connected by intricate hydrogen bonds into a three-dimensional supramolecular structure. These three compounds exhibit significant characteristic luminescence from the ligand to the central Ln(iii) ion, which is found by solid-state photoluminescence measurement. Sm-2 exhibits a long luminescence lifetime and high fluorescence quantum yield. A slow relaxation phenomenon is observed for the dysprosium compound by measuring the alternating-current susceptibility at low temperature and the underlying mechanism was further confirmed by theoretical calculations.

10.
RSC Adv ; 10(14): 8539, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35503283

RESUMO

[This corrects the article DOI: 10.1039/C9RA10975G.].

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