Uptake of Basic Blue 17 from aqueous solutions by using chemically crosslinked polyelectrolyte AAm AASS hydrogels
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
Authors: Uezuem, Oemer Baris; Karadag, Erdener
Abstract
In this study, the removal of a cationic thiazin dye such as Basic Blue 17 (Toluidin Blue, BB 17) by chemically crosslinked acrylamide (AAm)/acrylic acid sodium salt (AASS) hydrogels was investigated. Super water retainer AAm/AASS hydrogels with various compositions were prepared from ternary mixtures of AAm, AASS and water by free radical polymerization in aqueous solution using multifunctional crosslinkers such as ethylene glycol dimethacrylate (EGDMA), N,N' methylenebisacrylamide (NMBA), 1,4 butanediol dimethacrylate (BDMA) and trimethylolpropane triacrylate (TMPTA). Adsorption of Basic Blue 17 from aqueous solutions was studied by batch sorption technique at 25 degrees C. The effect of Basic Blue 17 concentration and mass of adsorbent on the dye adsorption were examined. In the experiments of the sorption, C type and L type sorption in the Giles classification system was found. Some binding parameters such as initial binding constant (K (i) ), equilibrium constant (K), monolayer coverage (n), site-size (u), and maximum fractional occupancy ((O) over cap) for AAm/AASS hydrogel-dye binding system were calculated by using Klotz linearization method. Finally, the amount of sorbed Basic Blue 17 per gram of dry hydrogel (q) was calculated to be 1.96-21.35 mu mol dye per gram for AAm/AASS hydrogels. Adsorption of Basic Blue 17 was changed range 39.17-96.63%. AAm/AASS hydrogels crosslinked by TMPTA, EGDMA, BDMA or NMBA can be used a sorbent in biotechnology, environment, sorption, separation, purification, immobilization and enrichment of some species.
Nandrolone combined with strenuous resistance training reduces vascular nitric oxide bioavailability and impairs endothelium-dependent vasodilation
STEROIDS
Authors: Guzzoni, Vinicius; Cunha, Tatiana Sousa; das Neves, Vander Jose; Briet, Larissa; Costa, Rafaela; Costa Sampaio Moura, Maria Jose; Oliveira, Vanessa; Pinho Franco, Maria do Carmo; Novaes, Pedro Duarte; Marcondes, Fernanda Klein
Abstract
Anabolic Androgenic Steroids (AASs) misuse has increased among adolescents and recreational athletes due to their potential effects on muscle hypertrophy. On the other hand, AAS might induce alterations on cardiovascular system, although some controversies regarding AAS on vascular properties remain unknown. To address this question, we aimed to investigate the effects of high doses of nandrolone combined with strenuous resistance training (RT) on function and structure of thoracic aorta. Rats were randomized into four groups: non-trained vehicle (NTV), trained vehicle (TV), non-trained nandrolone (NTN), and trained nandrolone (TN), and submitted to 6 weeks of treatment with nandrolone (5 mg/kg, twice a week) and/or resistance training. In vitro response of thoracic aorta to acetylcholine (ACh) was analyzed. Vascular nitric oxide (NO) and reactive oxygen species (ROS) synthesis were evaluated using 4,5-diaminofluorescein diacetate (DAF-2) and hydroethidine fluorescent techniques, respectively. Thoracic aorta was processed for microscopy analyses and tunica media thickness was measured. ACh-mediated relaxation response was impaired in endothelium intact aortic rings isolated from trained rats (TV and TN) as compared with their matched non-trained groups. TN rats showed reduced ACh-mediated vasodilatation than NTN rats. NO production and bioavailability decreased in thoracic aorta of nandrolone-treated rats in relation to their matched non-trained group (NTN vs. NW; TN vs. TV). ROS production and tunica media thickness were increased in TN rats when compared with TV rats. These findings indicate that high doses of nandrolone combined with strenuous RT affect NO bioavailability and might induce endothelial dysfunction and arterial morphological alterations.