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1.
Artículo en Inglés | MEDLINE | ID: mdl-28408067

RESUMEN

Anti-inflammatory property of polyphenols and their effect on the metabolism of prostaglandins is not established in healthy humans. This study aimed to evaluate the effect of polyphenol supplementation in plasma levels of prostaglandin E2 and other markers of inflammation and oxidative stress in women using contraceptives. In this randomized double-blind clinical trial, women aged 25-35 years were selected. Participants received capsules containing polyphenols or placebo, to be consumed for fifteen days. From 40 women randomized, 28 completed the study. Control group showed a significant increase in the levels of PGE2 (p=0.01) while the polyphenols group showed no change in these levels (p=0.79). There was an increase in hs-CRP (p<0.01) and F2-isoprostane (p=0.04) in the control group. The GSSG to GSH ratio significantly reduced in the polyphenols group (p=0.02). Supplementation with polyphenol capsules inhibited the increase in markers of inflammation and oxidative stress in women of childbearing age using combined hormonal contraceptives.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Polifenoles/administración & dosificación , Prostaglandinas E/sangre , Adulto , Antiinflamatorios no Esteroideos/farmacología , Cápsulas , Anticoncepción , Suplementos Dietéticos , Método Doble Ciego , F2-Isoprostanos/sangre , Femenino , Humanos , Polifenoles/farmacología , Reproducción
2.
Environ Sci Technol ; 37(16): 3709-15, 2003 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-12953885

RESUMEN

It has been known for a long time that certain additives (e.g., NaCl, CaCl2, Na2CO3, Fe2O3) can increase the sulfur dioxide capture-capacity of limestones. In a recent study we demonstrated that very small amounts of Na2CO3 can be very beneficial for producing sorbents of very high sorption capacities. This paper explores what contributes to these significant increases. Mercury porosimetry measurements of calcined limestone samples reveal a change in the pore-size from 0.04-0.2 microm in untreated samples to 2-10 microm in samples treated with Na2CO3--a pore-size more favorable for penetration of sulfur into the particles. The change in pore-size facilitates reaction with lime grains throughout the whole particle without rapid plugging of pores, avoiding premature change from a fast chemical reaction to a slow solid-state diffusion controlled process, as seen for untreated samples. Calcination in a thermogravimetric reactor showed that Na2CO3 increased the rate of calcination of CaCO3 to CaO, an effect which was slightly larger at 825 degrees C than at 900 degrees C. Peak broadening analysis of powder X-ray diffraction data of the raw, calcined, and sulfated samples revealed an unaffected calcite size (approximately 125-170 nm) but a significant increase in the crystallite size for lime (approximately 60-90 nm to approximately 250-300 nm) and less for anhydrite (approximately 125-150 nm to approximately 225-250 nm). The increase in the crystallite and pore-size of the treated limestones is attributed to an increase in ionic mobility in the crystal lattice due to formation of vacancies in the crystals when Ca is partly replaced by Na.


Asunto(s)
Contaminación del Aire/prevención & control , Carbonatos/química , Dióxido de Azufre/química , Adsorción , Contaminantes Atmosféricos/análisis , Carbonato de Calcio/química , Carbonatos/análisis , Tamaño de la Partícula , Porosidad
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