269 research outputs found

    Comparative effects of several cyclodextrins on the extraction of PAHs from a real contaminated soil

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    Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants (POPs) attracting extensive attention worldwide. Soils from many sites, such as areas of coal storage, coke oven plants, manufactured gas plants and areas of coal tar spillage present a high contamination level by PAHs. Due to their low solubility in water, the presence of PAHs in the soil matrix constitutes a long-term source of groundwater contamination, and their toxic, mutagenic and carcinogenic properties are responsible that the remediation of PAH-contaminated soil becomes a major environmental concern. In order to enhance the desorption rate of organic pollutants, various extracting agents have been used. Recently, cyclodextrins (CDs) have been proposed as an alternative agent to enhance the water solubility of hydrophobic compounds and thus their availability for biodegradation. The objectives of the present work were: to identify the level of PAHs of an aged-contaminated soil sample from a former chemical industry plant and to evaluate the ability of a natural cyclodextrin (ß-cyclodextrin, BCD) and three chemically modified cyclodextrins: 2-hydroxypropyl-ß-cyclodextrin (HPBCD), partially methylated-ß-cyclodextrin (PMBCD), and hydroxypropyl-¿-cyclodextrin (HPGCD) to extract the sixteen PAHs considered as priority pollutants by US-EPA. A real contaminated soil from the surrounding area of a deserted chemical industry situated in Asturias (North of Spain) was analyzed exhaustively in order to know its PAHs content. Then extraction experiments using Ca(NO3)2 solution or three types of different cyclodextrins solutions were carried out about the same soil. The results presented in this study show that according to Spanish legislation the analyzed soil had to be considered as contaminated soil. Its total PAHs content was about 1068.77±100.81 mg Kg-1, being phenanthrene, anthracene and naphthalene the most abundant compounds (25.3, 24.7 and 17.1 % of the total PAHs content of the soil, respectively). After the extractions experiments using CDs solutions, it was observed that the percentages of PAHs obtained were always higher than when an aqueous solution was used, although the three chemically modified cyclodextrins achieved higher extractions percentages than the natural cyclodextrin (BCD). From the sixteen selected PAHs, the highest extraction percentages was always obtained for the 3-rings PAHs, what is related with the more appropriated size and shape of this compounds with respect to the CDs cavity dimensions

    Comparative effects of several cyclodextrins on the extraction of PAHs from an aged contaminated soil

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    7 páginas.-- 3 figuras.-- 2 tablas.-- 52 referencias.-- Supplementary dataThe objective of the present study was to characterise the polycyclic aromatic hydrocarbons (PAHs) content of an aged contaminated soil and to propose remediation techniques using cyclodextrins (CDs). Four CDs solutions were tested as soil decontamination tool and proved more efficient in extracting PAHs than when an aqueous solution was used; especially two chemically modified CDs resulted in higher extraction percentages than natural β-CD. The highest extraction percentages were obtained for 3-ring PAHs, because of the appropriate size and shape of these compounds relative to those of the hydrophobic cavities of the CDs studied. A detailed mechanistic interpretation of the chemical modification of CDs on the extraction of the different PAHs has been performed, and connected with the role that the different hydrophobicities of the PAHs play in the extraction behaviour observed for the 16 PAHs, limiting their accessibility and the remaining risk of those PAHs not extractable by CDs. © 2013 Elsevier Ltd. All rights reserved.The authors thank to Dr. J.R. Gallego from the Universidad de Oviedo for providing the contaminated soil sample. Support from projects CTM2006-04626 and CTM2009-07335, Spanish Ministry of Science and Innovation (co-funded by Fondo Europeo de Desarrollo Regional, FEDER), are greatly appreciated. M.A. Sánchez-Trujillo acknowledges a research contract from CSIC (JAEPre 0800763) cofinanced by Fondo Social Europeo (FSE).Peer Reviewe

    Decontamination of polycyclic aromatic hydrocarbons and nonylphenol from sewage sludge using hydroxypropyl-β-cyclodextrin and evaluation of the toxicity of leachates

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    11 páginas.-- 2 tablas.-- 3 figuras.-- 61 referenciasA decontamination technique based in cyclodextrin extraction has been developed to eliminate nonylphenol (NP) and 16 polycyclic aromatic hydrocarbons (PAHs; the US Environmental Protection Agency priority pollutants list) from sewage sludge. In a first step, PAHs and NP were characterised in six sludges to determine contamination levels according to limit values proposed by the European Union Sludge Directive draft. There were few variations in the total PAHs content with levels of 1.88 to 3.05 mg kg-1. Three-ring PAHs predominated, but fluoranthene and pyrene were also present. None of the sludge exceeded the PAHs limit proposed by the European Union's draft Directive. On the contrary, NP content in four of the six sludges was over the recommended limits of 50 mg kg-1 for NP ethoxylates. With the aim of obtaining NP values below the concentration limits proposed to use the sewage sludge as agricultural amendments, a preliminary study using hydroxypropyl-β-cyclodextrin (HPBCD) extractions as a decontamination technique was carried out. About 90 % of NP content was removed with only one extraction with HPBCD, whereas after three sequential extractions using an aqueous solution without HPBCD, the NP extraction percentage was less than 1 %. Simultaneously, PAHs extraction percentages obtained with HPBCD were also much higher than when aqueous solution was used, especially in the case of two- and three-ring PAHs. Finally, the potential environmental hazard of HPBCD leachates to aquatic organisms (Daphnia magna) was tested. These results indicate that the treatment of sewage sludge with cyclodextrin could allow their safe use as fertiliser in agriculture. © 2013 Springer-Verlag Berlin Heidelberg.Support from projects CTM2006-04626 and CTM2009-07335, Spanish Ministry of Science and Innovation (cofunded by Fondo Europeo de Desarrollo Regional, FEDER), are greatly appreciated. M.A. Sánchez-Trujillo acknowledges a research contract from Consejo Superior de Investigaciones Científicas (CSIC, JAEPre 0800763) cofinanced by Fondo Social Europeo (FSE).Peer Reviewe

    Effectiveness of treatment with nebulized colistin in patients with COPD

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    To analyze whether the introduction of nebulized colistin in patients with chronic obstructive pulmonary disease (COPD) and infection with Pseudomonas aeruginosa (PA) is associated with a decrease of the number and duration of severe exacerbations. Thirty six patients with COPD and infection with PA treated with nebulized colistin attending a day hospital during a 5-year (January 2010-December 2014) period were prospectively included. Repeated-measures t -tests were used to assess whether the introduction of colistin was associated with changes in the number of exacerbations or the length of the hospitalizations, comparing for each patient the year prior to the introduction of colistin with the year after. After the introduction of colistin, the number of admissions decreased from 2.0 to 0.9 per individual year (P =0.0007), and hospitalizations were shorter (23.3 vs 10.9 days, P =0.00005). These results persisted when patients with and without bronchiectasis or with and without persistence of Pseudomonas were separately analyzed. No pre-post differences were detected in the number of exacerbations not requiring admission. Nebulized colistin seems associated with a strong decrease in the number and duration of hospitalizations due to exacerbation in patients with COPD and infection with PA. Clinical trials with a larger number of patients are needed in order to confirm these results

    Association of amount and duration of NRT use in smokers with cigarette consumption and motivation to stop smoking: A national survey of smokers in England.

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    Clinical trials have found that the use of nicotine replacement therapy (NRT) to reduce cigarette consumption results in significant declines in cigarette consumption and increases smokers' propensity to quit. However, observational "real-world" studies have found much smaller effects. This may be because of low levels of NRT use. This study examined the association between amount and duration of NRT use amongst those attempting to reduce their cigarette consumption with motivation to quit and cigarette consumption

    Efficacy and safety of intermittent intravenous outpatient administration of levosimendan in patients with advanced heart failure: the LION-HEART multicentre randomised trial

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    Aims: The LION-HEART study was a multicentre, double-blind, randomised, parallel-group, placebo-controlled trial evaluating the efficacy and safety of intravenous administration of intermittent doses of levosimendan in outpatients with advanced chronic heart failure. Methods and results: Sixty-nine patients from 12 centres were randomly assigned at a 2: 1 ratio to levosimendan or placebo groups, receiving treatment by a 6-hour intravenous infusion (0.2 mu g/kg/min without bolus) every 2weeks for 12weeks. The primary endpoint was the effect on serum concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) throughout the treatment period in comparison with placebo. Secondary endpoints included evaluation of safety, clinical events and health-related quality of life (HRQoL). The area under the curve (AUC, pg.day/mL) of the levels of NT-proBNP over time for patients who received levosimendan was significantly lower than for the placebo group {344 x 10(3) [95% confidence interval (CI) 283 x 10(3)-404 x 10(3)] vs. 535 x 10(3) [443 x 10(3)-626 x 10(3)], P = 0.003}. In comparison with the placebo group, the patients on levosimendan experienced a reduction in the rate of heart failure hospitalisation (hazard ratio 0.25; 95% CI 0.11-0.56; P = 0.001). Patients on levosimendan were less likely to experience a clinically significant decline in HRQoL over time (P = 0.022). Adverse event rates were similar in the two treatment groups. Conclusions: In this small pilot study, intermittent administration of levosimendan to ambulatory patients with advanced systolic heart failure reduced plasma concentrations of NT-proBNP, worsening of HRQoL and hospitalisation for heart failure. The efficacy and safety of this intervention should be confirmed in larger trials

    Ischemic aetiology, self-reported frailty, and gender with respect to cognitive impairment in chronic heart failure patients

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    Background: decisive information on the parameters involved in cognitive impairment in patients with chronic heart failure is as yet lacking. Our aim was to determine the functional and psychosocial variables related with cognitive impairment using the mini-mental-state examination (MMSE) with age-and education-corrected scores. Methods: a cohort study of chronic heart failure patients included in an integrated multidisciplinary hospital/primary care program. The MMSE (corrected for age and education in the Spanish population) was administered at enrolment in the program. Analyses were performed in 525 patients. Demographic and clinical variables were collected. Comprehensive assessment included depression (Yesavage), family function (family APGAR), social network (Duke), dependence (Barthel Index), frailty (Barber), and comorbidities. Univariate and multivariate logistic regression were performed to determine the predictors of cognitive impairment. Results: cognitive impairment affected 145 patients (27.6 %). Explanatory factors were gender (OR: 2.77 (1.75-4.39) p  3.5 (OR: 0.59 (0.35-0.99) p = 0.048), and beta-blocker treatment (OR: 0.36 (0.17 to 0.76, p = 0.007)). No association was found between cognitive impairment and social support or family function. Conclusion: the observed prevalence of cognitive impairment using MMSE corrected scores was 27.6 %. A global approach in the management of these patients is needed, especially focusing on women and patients with frailty, low albumin levels, and ischemic aetiology heart failure

    Association of neurexin 3 polymorphisms with smoking behavior.

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    The Neurexin 3 gene (NRXN3) has been associated with dependence on various addictive substances, as well as with the degree of smoking in schizophrenic patients and impulsivity among tobacco abusers. To further evaluate the role of NRXN3 in nicotine addiction, we analyzed single nucleotide polymorphisms (SNPs) and a copy number variant (CNV) within the NRXN3 genomic region. An initial study was carried out on 157 smokers and 595 controls, all of Spanish Caucasian origin. Nicotine dependence was assessed using the Fagerstrom index and the number of cigarettes smoked per day. The 45 NRXN3 SNPs genotyped included all the SNPs previously associated with disease, and a previously described deletion within NRXN3. This analysis was replicated in 276 additional independent smokers and 568 controls. Case-control association analyses were performed at the allele, genotype and haplotype levels. Allelic and genotypic association tests showed that three NRXN3 SNPs were associated with a lower risk of being a smoker. The haplotype analysis showed that one block of 16 Kb, consisting of two of the significant SNPs (rs221473 and rs221497), was also associated with lower risk of being a smoker in both the discovery and the replication cohorts, reaching a higher level of significance when the whole sample was considered [odds ratio = 0.57 (0.42-0.77), permuted P = 0.0075]. By contrast, the NRXN3 CNV was not associated with smoking behavior. Taken together, our results confirm a role for NRXN3 in susceptibility to smoking behavior, and strongly implicate this gene in genetic vulnerability to addictive behaviors

    Epidemiologia de l'hepatitis B a Catalunya

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    L'hepatitis és una malaltia coneguda de fa molt temps. Sembla (que la primera referència al seu caràcter contagiós prové del segle vuitè després de Crist, quan en una carta a sant Bonifaci, arquebisbe de Magúncia, el papa Zacaries li recomana que els malalts d'icterícia estiguin separats per tat d'evitar el contagi dels altres. La literatura mèdica antiga conté nombrosos exemples d'epidèmies d'icterícia, que retrospectivament podem interpretar com hepatitis, bé que ens pot quedar el dubte que es tractés d'altres malalties epidèmiques que també fan curs amb icterícia, com és ara la febre groga i la leptospirosi

    Seven-year mortality in heart failure patients with undiagnosed diabetes : an observational study

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    Background: Patients with type 2 diabetes mellitus and heart failure have adverse clinical outcomes, but the characteristics and prognosis of those with undiagnosed diabetes in this setting has not been established. Methods: In total, 400 patients admitted consecutively with acute heart failure were grouped in three glycaemic categories: no diabetes, clinical diabetes (previously reported or with hypoglycaemic treatment) and undiagnosed diabetes. The latter was defined by the presence of at least two measurements of fasting plasma glycaemia ≥ 7 mmol/L before or after the acute episode.Group differences were tested by proportional hazards models in all-cause and cardiovascular mortality during a 7-year follow-up. Results: There were 188 (47%) patients without diabetes, 149 (37%) with clinical diabetes and 63 (16%) with undiagnosed diabetes. Patients with undiagnosed diabetes had a lower prevalence of hypertension, dyslipidaemia, peripheral vascular disease and previous myocardial infarction than those with clinical diabetes and similar to that of those without diabetes. The adjusted hazards ratios for 7-year total and cardiovascular mortality compared with the group of subjects without diabetes were 1.69 (95% CI: 1.17-2.46) and 2.45 (95% CI: 1.58-3.81) for those with undiagnosed diabetes, and 1.48 (95% CI: 1.10-1.99) and 2.01 (95% CI: 1.40-2.89) for those with clinical diabetes. Conclusions: Undiagnosed diabetes is common in patients requiring hospitalization for acute heart failure. Patients with undiagnosed diabetes, despite having a lower cardiovascular risk profile than those with clinical diabetes, show a similar increased mortality
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