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1.
Water Sci Technol ; 75(5-6): 1051-1058, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28272034

RESUMEN

Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ), an efficient adsorbent for removal of Cd(II) and Pb(II) from aqueous solution, has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis. The influences of initial pH, contact time, and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were examined in detail. As for Cd(II) adsorption, kinetic adsorption can be explained by pseudo-second-order, while adsorption isotherm fits well with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 235.85 mg g-1 at 28 °C. Further thermodynamic investigation indicated that adsorption of Cd(II) by adsorbent Cell-g-PMA-HZ is endothermic and spontaneous under studied conditions. On the other hand, isotherm of Pb(II) adsorption fits well with Freundlich isotherm model and is more likely to be a physical-adsorption-dominated process. Consecutive adsorption-desorption experiments showed that Cell-g-PMA-HZ is reusable with satisfactory adsorption capacity.


Asunto(s)
Resinas Acrílicas/química , Cadmio/aislamiento & purificación , Celulosa/análogos & derivados , Celulosa/química , Hidrazinas/química , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Concentración de Iones de Hidrógeno , Iones/química , Cinética , Temperatura , Factores de Tiempo
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120303, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34454134

RESUMEN

Three isostructural lanthanide coordination polymers (LnCPs), [Ln(L)6(DMF)]n {HL = 2-(2-formylphenoxy) acetic acid, Ln = Sm (1); Eu (2); Tb (3)} have been synthesized by solvothermal reaction and characterized. Single crystal analyses revealed that the architectures of these LnCPs own one dimensional chain which can be further packed into two-dimensional architectures by hydrogen bonds. Moreover, these LnCPs can offer strategically placed uncoordinated formyl groups, which may act as hydrogen-bond acceptor in the sensing of nitro explosives. Luminescence measurements reveal that LnCPs 2 and 3 exhibit strong luminescence in solid states. LnCP 2 shows quick, highly selective and sensitive detection of 2,4,6-trinitrophenol (TNP) with the high quenching constant (2.6 × 104 M-1) and low detection limit (3.39 µM), which indicates that LnCP 2 is more efficient than most of Eu-based coordination polymers for the sensing of TNP. Furthermore, LnCP 2 represents the first example of one-dimensional Eu-based sensors with formyl group as hydrogen-bonding site in the detection of TNP.


Asunto(s)
Europio , Elementos de la Serie de los Lantanoides , Luminiscencia , Picratos , Polímeros
3.
Cell Reprogram ; 19(5): 324-330, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28910136

RESUMEN

Neuropilin-1 (NRP1) is one of the members of neuropilin family. It can combine with disparate ligands involved in regulating cell proliferation, apoptosis, and differentiation. The binding of NRP1 to Sema3A stimulates osteoblast differentiation through the classical Wnt/ß-catenin pathway. However, the functions of NRP1 in dental pulp stem cells (DPSCs) are not clear. The aim of our study was to investigate how NRP1 controlled odontoblast differentiation in DPSCs and clarified the underlying mechanisms. NRP1 expression was increased in time-dependent manner along with cell odontoblast differentiation. Overexpression of NRP1 upregulated dentin matrix protein-1, dentin sialophosphoprotein, alkaline phosphatase protein level, and mineralization in DPSCs, while knockdown of NRP1 induced the opposite effects. SiNRP1 similar to DKK1 availably blocked classical Wnt/ß-catenin signaling and odontoblast differentiation. In summary, NRP1, as a promoter of odontoblast differentiation, regulates DPSCs via the classical Wnt/ß-catenin pathway.


Asunto(s)
Diferenciación Celular , Pulpa Dental/metabolismo , Regulación de la Expresión Génica , Neuropilina-1/biosíntesis , Odontoblastos/metabolismo , Células Madre/metabolismo , Vía de Señalización Wnt , Adolescente , Adulto , Pulpa Dental/citología , Femenino , Humanos , Masculino , Neuropilina-1/genética , Odontoblastos/citología , Células Madre/citología
4.
Cancer Biol Ther ; 14(10): 907-15, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23917379

RESUMEN

Free radicals are formed as a result of cellular processes and play a key role in predisposition to and development of numerous diseases and of premature aging. Recently, we reported the syntheses of a number of novel phenolic antioxidants for possible application in food industry. In the present study, analyses of the cellular processes and molecular gene expression effects of some of the novel antioxidants in normal human tissues and in cancer cells were undertaken. Results indicated that whereas the examined antioxidants showed no effects on morphology and gene expression of normal human oral and gingival epithelial tissues, they exerted a profound cell killing effect on breast cancer cells, including on chemotherapy-resistant breast cancer cells and on oral squamous carcinoma cells. Among the tested antioxidants, N-decyl-N-(3-methoxy-4-hydroxybenzyl)-3-(3,4-dihydroxyphenyl) propanamide and N-decyl-N-(3,5-dimethoxy-4-hydroxybenzyl)-3-(3,4-dihydroxyphenyl) propanamide were the most promising, with excellent potential for cancer treatment. Moreover, our gene expression databases can be used as a roadmap for future analysis of mechanisms of antioxidant action.


Asunto(s)
Antineoplásicos/toxicidad , Antioxidantes/toxicidad , Lípidos/toxicidad , Antineoplásicos/farmacología , Antioxidantes/farmacología , Ácidos Cafeicos/farmacología , Ácidos Cafeicos/toxicidad , Caspasa 3/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteínas de Unión al ADN/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Expresión Génica/efectos de los fármacos , Histonas/metabolismo , Humanos , Hidroxibenzoatos/farmacología , Hidroxibenzoatos/toxicidad , Lípidos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Células MCF-7 , Proteína Homóloga de MRE11 , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo
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