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Rising use of nanoparticles in manufacturing as well as in commercial products bring issues related to environmental release and human exposure. A large amount of TiO2 nanoparticles will eventually reach wastewater treatment plants. Low pressure membrane filtration has been suggested as a feasible treatment of water streams. This study investigated first at laboratory scale the influence of: i) membrane material, ii) pore size and iii) water chemistry on nTiO2 removal. TiO2 retention was governed by the cake layer formation mechanism and significant retention of nanoparticles was observed even for filters having considerably larger pores than nTiO2. PVDF showed a great potential for nTiO2 rejection. Additionally, filtration pilot plant experiments were carried out using PVDF membranes (0.03 and 0.4 μm pore size). The release of nTiO2 in the pilot scale filtration system was always above the instrumental detection limit (> 1.5 μg/L) and in most cases below 100 μg/L regardless of the pore size and applied conditions. The nTiO2 membrane breakthrough predominantly occurred in the first few minutes after backwashes and ceased when the cake layer was formed. Ultrafiltration and microfiltration were comparable with rejection of nTiO2 above 95% at similar permeate flow rates. Nevertheless, ultrafiltration is more promising than microfiltration because it allowed longer operation times between backwash cycles. This work was funded by the Provincial Government of Bizkaia (6-12-TK-2010-0013).

Objective The aim of this study was to examine whether resveratrol might represent a promising therapeutic tool with which to combat adipose tissue chronic inflammation in a model of genetic obesity and to link its anti-inflammatory activity with its effect on body fat reduction. Methods Twenty 6-wk-old male Zucker (fa/fa) rats were randomly distributed into two experimental groups. Resveratrol (RSV) was given orally (15 mg/kg body weight/d in RSV group) by means of an orogastric catheter for 6 wk. Enzyme activities were measured spectrophotometrically or fluorimetrically. Gene and protein expressions were analyzed by reverse transcriptase polymerase chain reaction and Western blot respectively. Cytokine concentrations and the activity of nuclear factor κ-light-chain-enhancer of activated β cells (NF-κB) were measured by using commercial kits. Results RSV reduced the weight of internal adipose tissues. In epididymal depot glucose-6P-dehydrogenase, acetyl-CoA carboxylase activities, as well as lipoprotein lipase expression and activity were reduced by RSV. The expression of hormone-sensitive lipase was increased, and that of the cluster of differentiation 36 was reduced. Serum concentrations of tumor necrosis factor-α, monocyte chemoattractant protein 1, and C-reactive protein were lower in the RSV-treated group than in the control group. Protein expression of interleukin-6 and the activity of NF-κB, were decreased by RSV. Conclusion The present results provide evidence that fatty acid uptake and lipolysis are metabolic pathways involved in the response of adipose tissue to RSV. This polyphenol modulates plasma cytokine levels partially by reducing macrophage infiltration in adipose tissue and inhibiting NF-κB activity.

Resumen La diabetes mellitus tipo 2 (DM2) es una enfermedad muy frecuente a escala mundial y representa una gran causa de morbimortalidad. Su prevalencia ha aumentado enormemente en las ultimas decadas y si no se toman medidas la magnitud del problema crecera, con consecuencias para el paciente, para el sistema de salud y para los factores socioeconomicos. Esta demostrado que los cambios en el estilo de vida pueden prevenir el desarrollo de DM2 siempre y cuando se optimice la prescripcion de actividad fisica y aspectos nutricionales para este tipo de pacientes. Asi, esta revision trata del principal transportador de glucosa en el musculo esqueletico, el GLUT4, y pretende conseguir un mejor entendimiento de su implicacion a nivel molecular y su rol frente a distintos estimulos de nutricion y actividad fisica. Finalmente, se proponen aplicaciones practicas para la prescripcion de actividad fisica en la DM2.

The occurrence and removal rate of seven pharmaceuticals (ibuprofen, naproxen, diclofenac, fluoxetine, ofloxacin, norfloxacin, ciprofloxacin), two metabolites (norfluoxetine, clofibric acid), one degradation product (4-isobutylacetophenone) and 3 estrogens (17alpha-ethinylestradiol, 17beta-estradiol, estrone) were studied in the inlet and outlet of a tertiary sewage treatment plant (STP) in Sweden as well as between different treatment steps in the STP which includes a conventional activated sludge step. Pharmaceuticals in raw household and raw hospital sewage streams leading to the STP were as well investigated. Hydraulic retention times (HRT) of each treatment step was considered for sampling and for the calculation of the removal rates. These rates were above 90%, except for diclofenac, clofibric acid, estrone and ofloxacin. However, only diclofenac and naproxen showed significant effluent loads (>145 mg/d/1000 inh). Diclofenac was not eliminated during the treatment and in fact even higher concentrations were found at the effluent than in the inlet of the STP. 17alpha-Ethinylestradiol was not detected in any of the samples. Results indicate that a STP such as the one in Kristianstad, Sweden, with a tertiary treatment is sufficient to remove significantly most of the investigated pharmaceuticals. The chemical treatment improved the removal of several pharmaceuticals especially the antibiotics, which showed step removal rates between 55 and 70%. The expected concentration levels of the pharmaceuticals in the surface water (dilution 1 to 10) close to the outlet of the STP are below the no-observed effect-concentration (NOEC). However, despite that this would imply no important effects in the aquatic environment one cannot rule out negative consequences nearby the STP because most of the NOEC values are derived from acute toxicity data. This may underestimate the real impact of pharmaceuticals in the aquatic ecosystem.

In this study, a method was developed for determination of the free concentration of 4-isobutylacetophenone, a toxic degradation product of ibuprofen, in river and sewage water samples from Sweden. Sample preparation and analysis were performed by a hollow-fibre microporous membrane liquid-liquid extraction (HF-MMLLE) set-up and gas chromatography-mass spectrometry (GC-MS), respectively. In this novel approach, only the liquid in the membrane pores is utilised for non-depleting extraction. Several parameters were studied, including: type of organic solvent, sample pH, and salt and humic acid content. The optimised method allowed the determination of the analyte at the ng L(-1) level in river and sewage water. A linear plot gave a correlation coefficient better than 0.992 and resulted in a limit of detection of 7 and 14 ng L(-1) for river and sewage water, respectively. The enrichment factor was over 2000 in the fibre and over 300 after dilution. The repeatability and reproducibility were better than 5% and 10%, respectively. For the first time, 4-isobutylacetophenone was found at free concentrations of 40 ng L(-1) or below in sewage waters, while it could not be quantified in a river downstream from a municipal sewage treatment plant.