The effect of ionic Co presence on the structural, optical and photocatalytic properties of modified cobalt–titanate nanotubes

With the aim of producing materials with enhanced optical and photocatalytic properties, titanate nanotubes (TNTs) modified by cobalt doping (Co-TNT) and by Na+ -> Co ion-exchange (TNT/Co) were successfully prepared by a hydrothermal method. The influence of the doping level and of the cobalt position in the TNT crystalline structure was studied. Although no perceptible influence of the cobalt ion position on the morphology of the prepared titanate nanotubes was observed, the optical behaviour of the cobalt modified samples is clearly dependent on the cobalt ions either substituting the Ti4+ ions in the TiO6 octahedra building blocks of the TNT structure (doped samples) or replacing the Na+ ions between the TiO6 interlayers (ion-exchange samples). The catalytic ability of these materials on pollutant photodegradation was investigated. First, the evaluation of hydroxyl radical formation using the terephthalic acid as a probe was performed. Afterwards, phenol, naphthol yellow S and brilliant green were used as model pollutants. Anticipating real world situations, photocatalytic experiments were performed using solutions combining these pollutants. The results show that the Co modified TNT materials (Co-TNT and TNT/Co) are good catalysts, the photocatalytic performance being dependent on the Co/Ti ratio and on the structural metal location. The Co(1%)-TNT doped sample was the best photocatalyst for all the degradation processes studied.

Effect of a sardine supplement on C-reactive protein in patients receiving hemodialysis

Objective - The study evaluated the effect of a canned sardine supplement in C-reactive protein (CRP) in patients on hemodialysis (HD) and the compliance and adherence to this supplement. Design - This was a quasi-experimental study: Participants with a serum CRP of 5 mg/dL or less volunteered to consume a sardine supplement or were maintained on the usual cheese/ham sandwich supplement. Setting - The study took place in two outpatient dialysis units in Lisbon, Portugal. Patients - The study comprised 63 patients receiving maintenance HD three times per week for at least 6 months and an initial CRP concentration of 5 mg/dL or less. Exclusion criteria included the presence of graft vascular access or history of cancer. Intervention - After a 4-week washout period, the nutritional intervention included a canned sardine sandwich for the case group (n = 31) and a cheese or ham sandwich for the control group (n = 32), to be ingested during each routine HD session, 3 times per week, for 8 weeks. Main outcome measure - Serum levels of high-sensitivity CRP were the outcome measure. Results - Only 65 patients from the invited 186 patients met the inclusion criteria and agreed to eat the sardine sandwich supplement three times per week and were involved in the study. A significant proportion of 48% (n = 31, case group) consumed the sardine sandwich supplement three times per week for 8 weeks, fulfilling the requirements and completing the study. The present investigation showed that a sardine sandwich supplement had no effect on CRP levels among patients on HD. However, when participants were stratified according to tertiles of CRP distribution values at baseline, a reduction in CRP levels was found for those in the higher tertile, being higher for the case group (P = .047). Although diabetic patients were excluded from the analysis (eight in the sardine supplementation group and seven in the control group) a significant CRP reduction was found (P = .034). Conclusion - Although a supplement of low-dose n-3 long-chain polyunsaturated fatty acids had no effect on the plasma high-sensitivity CRP of the supplemented group, a reduction in CRP levels was found when patients were stratified for tertiles of CRP (for the upper tertile) and diabetic status (for nondiabetic patients). These findings need to be further confirmed. This canned sardine supplement was accepted by an important proportion of patients, enhancing diet variety and contributing for a greater n-3 long-chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid intake.