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1.
Environ Res ; 209: 112868, 2022 06.
Article in English | MEDLINE | ID: mdl-35143803

ABSTRACT

A fruit processing wastewater was submitted to different advanced oxidation processes, namely, electro-Fenton (EF), electrochemical oxidation (EO), activated persulfate (PS), and combined EF/PS. The performance of the treatment processes, at different experimental conditions, regarding organic load removal, biodegradability increment, toxicity reduction, and specific energy consumption (Esp), was evaluated. At the experimental conditions studied, EO led to the treated solutions with the highest biodegradability increment, from 0.24 to 0.48, and toxicity reduction towards Daphnia magna, from 5.8 to 1.5 toxic units, without requiring the addition of chemicals. Nevertheless, the highest chemical oxygen demand (COD) removals were obtained for EF and combined EF/PS treatments. For the electrochemical processes, an increase in COD removal rate with applied current density (j) was observed. However, the increase in j substantially raised the Esp. In PS treatment, COD removals above 80% were only achieved for high amounts of added persulfate and iron, which led to less biodegradable and more toxic solutions. Combined EF/PS attained the lowest Esp values, mainly due to the conductivity increase originated by the persulfate and iron salts addition. Besides the disadvantage of the chemicals added, this combined treatment led to treated solutions with very acidic pH and significant iron content.


Subject(s)
Wastewater , Water Pollutants, Chemical , Biological Oxygen Demand Analysis , Fruit/chemistry , Hydrogen Peroxide , Oxidation-Reduction , Waste Disposal, Fluid , Wastewater/chemistry , Wastewater/toxicity , Water Pollutants, Chemical/analysis
2.
Chemosphere ; 205: 433-442, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29705634

ABSTRACT

The electrodegradation of the 4-aminonaphthalene-1-sulfonic acid (4AN1S), 5-aminonaphthalene-2-sulfonic acid (5AN2S) and 8-aminonaphthalene-2-sulfonic acid (8AN2S) was studied, using two electrode materials as anode, BDD and Ti/Pt/PbO2, and two different electrolytes, sodium sulfate and sodium chloride. The highest COD removal rates were obtained at BDD: for 5AN2S and 8AN2S results were similar in both electrolytes; for 4AN1S, results were better in sodium chloride. The lowest COD removal rates were obtained at the system Ti/Pt/PbO2-sodium sulfate, for all the studied amines. The dissolved organic carbon (DOC) removal was much higher at BDD for all the amines, in sulfate for 5AN2S and 8AN2S and in chloride for 4AN1S. Nitrogen removal was always almost irrelevant in sulfate medium but higher than 60%, after 6-h assays, in chloride. The highest combustion efficiencies were attained at the system BDD-sodium sulfate and were: 4AN1S-75%; 5AN2S-84%; 8AN2S-74%. HPLC results show that total degradation of the studied aminonaphthalene sulfonates is attained at both anode materials, utilizing any of the electrolytes, with a first order kinetics. However, kinetic constants obtained with the variation of the amines concentration in time are 10-40 times higher in chloride, being slightly higher at Ti/Pt/PbO2 than at BDD. Regarding the presence of carboxylic acids during the degradation assays, it was observed that the electrolysis of the amines 5AN2S and 8AN2S always lead to higher amounts of oxalic acid and lower quantities of acetic acid than the electrolysis of the amine 4AN1S.


Subject(s)
Amines/chemistry , Electrolysis/methods , Naphthalenes/chemistry , Electrodes , Kinetics , Nitrogen , Oxidation-Reduction , Sulfates , Sulfonic Acids/chemistry , Titanium , Water Pollutants, Chemical/chemistry
3.
Rev Calid Asist ; 32(1): 50-56, 2017.
Article in Spanish | MEDLINE | ID: mdl-27614929

ABSTRACT

OBJECTIVE: Within the framework of the PaSQ (Patient Safety and Quality care) Project, this hospital decided to implement a multifaceted hospital-wide Hand Hygiene (HH) intervention based on a multimodal WHO approach over one year, focusing on achieving a sustained change in HH cultural change in this hospital. MATERIAL AND METHODS: Setting: University Hospital Marqués de Valdecilla, Santander (Spain), a tertiary hospital with 900 beds. Intervention period: 2014. An action plan was developed that included the implementation of activities in each component of the 5-step multimodal intervention. An observation/feedback methodology was used that included the provision of performance and results feedback to the staff. A 3/3 strategy (non-blinded direct observation audits performed during 3 randomised days every 3 weeks with pro-active corrective actions at the end of each observation period). HH compliance, alcohol-based hand-rub (ABHR) consumption, and rate of MRSA infection, were monitored during the intervention. RESULTS: Hospital ABHR consumption increased during the study period: from 17.5 to 19.7mL/patient-days. In the intervention units, this consumption was 24.8mL pre-intervention, 42.5mL during the intervention, and 30.4mL two months post-intervention. There were 137 evaluation periods in 30 different days, in which a total of 737 health-care workers were observed and 1,870 HH opportunities. HH compliance was 54.5%, ranging between 44.8% and 69.9%. The incidence of MRSA infection decreased during the intervention in the selected units, from 13.2 infections per 10,000 patient-days pre-intervention to 5.7 three months post-intervention. CONCLUSIONS: Our HH strategy, supported by a 3/3 strategy increased alcohol-based hand-rub consumption and compliance. A reduction in MRSA infections was observed.


Subject(s)
Guideline Adherence , Hand Hygiene , Hospitals, University/organization & administration , Infection Control/organization & administration , Checklist , Cross Infection/epidemiology , Cross Infection/prevention & control , Drug Utilization , Formative Feedback , Hand Disinfection/methods , Hand Hygiene/standards , Hand Sanitizers , Hospital Units , Humans , Infection Control/methods , Methicillin-Resistant Staphylococcus aureus , Organizational Culture , Personnel, Hospital/education , Personnel, Hospital/psychology , Pilot Projects , Spain , Staphylococcal Infections/epidemiology , Staphylococcal Infections/prevention & control
4.
Environ Sci Pollut Res Int ; 24(12): 11102-11110, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27522198

ABSTRACT

The Sr1 - x La x TiO3 (0 ≤ x ≤ 0.4) and Sr1 - x Bi x TiO3 (0 ≤ x ≤ 0.3) perovskites were prepared via solid state reaction by partially replacing the Sr2+ ions in the SrTiO3 structure by La3+ or Bi3+ ions, characterized and utilized as photocatalysts immobilized in Ni-foam substrate in the degradation of the azo dye Acid Orange 7 (AO7). For both perovskite families, the XRD data reveal the existence of a predominant well-crystallized phase, belonging to a cubic perovskite in a Pm3m space group, with the presence of other minority phases. The characteristic dimension and the volume of the cell decrease with the introduction in the SrTiO3 lattice of the La3+ or Bi3+ ions. The grain size of the Sr1 - x La x TiO3 samples is around 100 nm and slightly lower for the Sr1 - x Bi x TiO3 samples. Regarding the utilization of the prepared perovskite powders deposited over the Ni-foam substrates as catalysts in the photodegradation of AO7 solutions, the results show an improvement in the performance of the films of the substituted perovskite when compared to the SrTiO3 perovskite, being the best results obtained with Sr0.9Bi0.1TiO3.


Subject(s)
Azo Compounds/chemistry , Benzenesulfonates/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Photolysis , Titanium/chemistry , Catalysis , Strontium/chemistry
5.
Sci Total Environ ; 541: 282-291, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26410703

ABSTRACT

The influence of applied current density and chloride ion concentration on the ability of Ti/Pt/PbO2 and Ti/Pt/SnO2-Sb2O4 anodes for the electrochemical oxidation of humic acid and sanitary landfill leachate samples was assessed and compared with that of BDD anode. For the experimental conditions used, results show that both organic load and nitrogen removal rates increase with the applied current density and chloride ion concentration, although there is an optimum COD/[Cl-]0 ratio below which there is no further increase in COD removal. Metal oxide anodes present a similar performance to that of BDD, being the results obtained for Ti/Pt/PbO2 slightly better than for Ti/Pt/SnO2-Sb2O4. Contrary to BDD, Ti/Pt/PbO2 promotes lower nitrate formation and is the most suitable material for total nitrogen elimination. The importance of the optimum ratio of Cl-/COD/NH4 +initial concentrations is discussed.

6.
Environ Sci Pollut Res Int ; 21(14): 8457-65, 2014.
Article in English | MEDLINE | ID: mdl-24664638

ABSTRACT

The anodic oxidation of tetracycline was performed in an up-flow reactor, operating in batch mode with recirculation, using as anode a boron-doped diamond electrode. The influence on the degradation rate of solution initial pH (2 to 12), applied current intensity (25 to 300 A m(-2)) and type of electrolyte (sodium sulphate or sodium chloride) were investigated. For the assays run at equal current density, with sodium sulphate as electrolyte, the solution's initial pH of 2 presented the highest absorbance and chemical oxygen demand removals. Regarding the influence of current density, for equal charge passed, the organic load removal rate decreased with the increase in applied current. When sodium sulphate was used as an electrolyte, high-performance liquid chromatography (HPLC) results have shown an almost complete removal of tetracycline after a 2-h assay. HPLC results have also shown the presence of oxamic acid as one of the intermediates of tetracycline anodic oxidation. The complete removal of tetracycline was much faster in the presence of chloride ions that promoted the complete degradation of this antibiotic in 30 min. However, in the presence of chloride ions, the tetracycline mineralization is slower, as observed by the lower organic carbon removal rate when compared to that of the tetracycline degradation in the presence of sulphate.


Subject(s)
Anti-Bacterial Agents/chemistry , Tetracycline/chemistry , Water Pollutants, Chemical/chemistry , Biological Oxygen Demand Analysis , Boron/chemistry , Chromatography, High Pressure Liquid , Diamond/chemistry , Electrodes , Hydrogen-Ion Concentration , Oxidation-Reduction , Sodium Chloride/chemistry , Sulfates/chemistry , Water Purification/methods
7.
J Hazard Mater ; 199-200: 82-7, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-22100223

ABSTRACT

In the present study, the anodic oxidation of a leachate from an intermunicipal sanitary landfill was evaluated using a boron-doped diamond anode as a possible post-treatment to the biological one, in order to diminish the remaining bio-refractory organic matter. The influence of the dilution of the leachate sample and the applied current density on the performance of electrochemical oxidation was investigated. For the different assays performed, a comparison between the theoretical kinetic model for organic mineralization, proposed in the literature, and experimental data was done and the best correspondences were attained at lower applied current density for sample without dilution and at higher applied current density for the more diluted sample. However, the energetic most favourable treatment is attained for sample without dilution at very low current density. The DOC/COD ratio was also analysed and apparently, the mineralization of the organic matter improves with the dilution of the leachate samples.


Subject(s)
Boron/chemistry , Diamond , Electrodes , Electrochemistry , Kinetics , Oxidation-Reduction
8.
J Hazard Mater ; 186(2-3): 1033-41, 2011 Feb 28.
Article in English | MEDLINE | ID: mdl-21168968

ABSTRACT

The electrochemical oxidation of four aromatic amines, with different substituent groups, 3-amino-4-hydroxy-5-nitrobenzenesulfonic acid (A1), 5-amino-2-methoxybenzenesulfonic acid (A2), 2,4-dihydroxyaniline hydrochloride (A3) and benzene-1,4-diamine (A4), was performed using as anode a boron-doped diamond electrode, commercially available at Adamant Technologies. Tests were run at room temperature with model solutions of the different amines, with concentrations of 200 ppm, using as electrolyte 0.035 M Na(2)SO(4) aqueous solutions, in a batch cell with recirculation, at different current densities (200 and 300 A m(-2)). The following analyses were performed with the samples collected during the assays: UV-Vis spectrophotometry, chemical oxygen demand (COD), total organic carbon (TOC), total Kjeldahl nitrogen, ammonia nitrogen, nitrates and HPLC. Results have shown a good electrodegradation of all the amines tested, with COD removals, after 6 h assays, higher than 90% and TOC removals between 60 and 80%. Combustion efficiency (η(C)), which measures the tendency to convert organic carbon to CO(2), was also determined for all the amines, being η(CA1)<η(CA2)<η(CA3)<η(CA4)=0.99.


Subject(s)
Amines/analysis , Boron Compounds/chemistry , Diamond , Electrodes , Hydrocarbons, Aromatic/analysis , Biological Oxygen Demand Analysis , Carbon/chemistry , Chromatography, High Pressure Liquid , Electrochemistry , Incineration , Oxygen/chemistry , Spectrophotometry, Ultraviolet
9.
J Oral Rehabil ; 38(2): 120-35, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20678103

ABSTRACT

A question frequently asked in the clinical practice of the professional who treats temporomandibular joint disorders (TMJD) is 'To make the cost/benefit ratio worthwhile for the patient, when should I request a temporomandibular joint (TMJ) computed tomography (CT) or magnetic resonance imaging (MRI)?' To evaluate the evidence of the efficacy of CT and MRI in the diagnosis of disc displacement, local inflammatory disorders, and arthrosis of the TMJ at therapeutic efficacy level, PubMed and Cochrane literature searches with specific indexing terms and a hand search were made. From the retrieved titles and abstracts, three examiners selected publications on the basis of predetermined inclusion and exclusion criteria. Data were extracted from the selected publications using a previously established protocol. Publications considered relevant were interpreted with the aid of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool and publications that critically evaluate systematic reviews. The literature search yielded 584 titles and abstracts, of which 257 were selected and read in full text. One study was judged relevant. This study evaluated evidence of the efficacy of MRI in the diagnosis of disc position and configuration, disc perforation, joint effusion, and osseous and bone marrow changes in the temporomandibular joint, but no publication reported diagnostic thinking efficacy or therapeutic efficacy. In conclusion, the absence of studies on the therapeutic efficacy of MRI and CT on TMJD reinforces the need for investment in decision-making studies; meanwhile, sectional imaging tests should be prescribed with caution, especially when health budgets are limited.


Subject(s)
Magnetic Resonance Imaging/statistics & numerical data , Temporomandibular Joint Disorders/diagnosis , Temporomandibular Joint Disorders/therapy , Tomography, X-Ray Computed/statistics & numerical data , Cost-Benefit Analysis , Decision Support Techniques , Humans , Quality Assurance, Health Care
10.
Chemosphere ; 79(6): 637-45, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20207390

ABSTRACT

The electrochemical oxidation of aniline (AN) and ortanilic (OA), metanilic (MA) and sulfanilic (SA) acids was performed using as anode a boron-doped diamond (BDD) electrode. Tests were performed with model solutions of the different amines, with concentrations of 200mg L(-1), using as electrolyte 0.035 M Na2SO4, in a batch cell, with re-circulation, at different current densities (200 and 300 A m(-2)). Samples were collected at pre-selected intervals and absorbance measurements, Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), Total Kjeldahl Nitrogen, Ammonia Nitrogen, Nitrates and Nitrites and HPLC analysis were performed. Results have shown a good elimination of the persistent pollutant, with COD and TOC removals always higher than, respectively: AN--91% and 90%; OA--75% and 82%; MA--88% and 87%; and SA--85% and 79%. The combustion efficiencies, calculated for the first hour of the runs, for the 300 A m(-2) assays, were the following: AN--0.93; OA--0.28; MA--0.82; and SA--0.83. For all the amines studied, after 6h degradation only oxalic and maleic acids were identified by HPLC.


Subject(s)
Amines/chemistry , Aniline Compounds/chemistry , Carcinogens, Environmental/chemistry , Electrolysis/methods , Sulfones/chemistry , Carbon/isolation & purification , Chromatography, High Pressure Liquid , Electrodes , Nitrogen/isolation & purification , Oxygen/isolation & purification , Spectrophotometry , Waste Disposal, Fluid/methods
11.
Ann Rheum Dis ; 63(1): 54-60, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14672892

ABSTRACT

OBJECTIVES: To investigate the phenotype and T cell receptor (TCR) use in peripheral blood T cells in patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA). METHODS: Circulating T lymphocyte phenotype and TCR repertoire were studied by flow cytometry using specific monoclonal antibodies in 23 healthy controls and 37 patients with PMR/GCA. RESULTS: Patients with active PMR/GCA showed an inverse relation between naive and memory CD4+ T cells and unchanged expression of activation surface markers compared with controls. CD4+ TCR BV expansions were seen in 12 (52%) controls and in 8 (22%) patients with active disease (p = 0.03). Within the CD8+ subset, the frequency of expansions was similar between groups. Most T cell expansions remained stable over time. Seventeen of the 23 patients with active PMR/GCA disclosed a simultaneous CD4+ and CD8+ T cell depletion for at least one particular BV family with a clear predominance of BV5S2/S3. CONCLUSIONS: The phenotype of circulating T cells in patients with PMR/GCA is similar to that found in aged healthy subjects, except for the surface markers of naive and memory cells and a striking non-activated phenotype. Specific BV expansions in CD4+ and CD8+ T cells, which remain stable over time, are frequent in aged subjects, including patients with PMR/GCA. TCR BV changes in patients with active disease seem to be also age related, except for the significant decrease in certain BV families in both CD4+ and CD8+ T cell subsets, which may favour the participation of a superantigen stimulation in PMR/GCA.


Subject(s)
Giant Cell Arteritis/immunology , Polymyalgia Rheumatica/immunology , Receptors, Antigen, T-Cell, alpha-beta/blood , T-Lymphocyte Subsets/immunology , Aged , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Female , HLA-DR Antigens/blood , HLA-DRB1 Chains , Histocompatibility Testing , Humans , Immunophenotyping , Male , Middle Aged , Superantigens/immunology
12.
Rheumatology (Oxford) ; 41(10): 1119-25, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12364630

ABSTRACT

OBJECTIVE: To investigate the pathogenic mechanism of reactive arthritis after instillation of Calmette-Guérin bacillus (BCG). Although the clinical features of reactive arthritis after BCG therapy are well described, only a few reports have studied the possible pathogenic mechanisms. METHODS: We analysed by flow cytometry the phenotype and T-cell receptor (TCR) expression of peripheral blood (PB) and synovial fluid (SF) T cells in a patient who developed reactive arthritis (ReA) following intravesical BCG immunotherapy for bladder cancer. The proliferative response of short-term T-cell lines (TCL) from PB of this patient to mycobacterial antigens was tested by bromodeoxyuridine incorporation. RESULTS: CD4(+) and CD8(+) SF T cells with activated and memory phenotype were observed at the onset of arthritis. We were able to detect BV-restricted expansion of CD8(+) T cells in PB (BV17) and in SF (BV5S1 and BV12). The percentage of PB and SF CD8(+) T cells that expanded diminished when the symptoms remitted. The strongest response of CD4(+) TCL from the patient in vitro was obtained for human hsp-60 in an inversely dose-dependent manner. Very important was the finding that CD8(+) TCL from the patient demonstrated no proliferative response to any antigenic challenge that was reversed after the addition of exogenous interleukin 2. CONCLUSION: Although the identity of the stimulating antigen that led to the expansions observed in this patient is not clarified by the present data, both CD4(+) and CD8(+) T cells might play a role in the development of ReA following intravesical administration of BCG.


Subject(s)
Arthritis, Reactive/etiology , Immunotherapy/adverse effects , Mycobacterium bovis , T-Lymphocyte Subsets/cytology , Urinary Bladder Neoplasms/therapy , Arthritis, Reactive/immunology , CD4-CD8 Ratio , Cell Division , Cell Line , Humans , Immunoglobulin Variable Region , Immunophenotyping , In Vitro Techniques , Male , Middle Aged , Prohibitins , Receptors, Antigen, T-Cell, alpha-beta/analysis , Synovial Fluid/cytology , Synovial Fluid/immunology , T-Lymphocyte Subsets/chemistry , Tuberculin/administration & dosage
14.
Semin Arthritis Rheum ; 30(4): 257-71, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11182026

ABSTRACT

BACKGROUND AND OBJECTIVE: During the last few years, there have been several studies on T cell subsets in polymyalgia rheumatica (PMR) and giant cell arteritis (GCA), with conflicting results. Whereas some authors have found normal values of circulating CD8+ T cells, others have found a decreased number. Furthermore, in some studies, the level of CD8+ cells was found to be related to disease activity, and it has been proposed that a decrease of CD8+ T cells be used as a diagnostic criterion for PMR. The purpose of our study was to determine the value of assessing T cell subsets in PMR and GCA. METHODS: T lymphocyte subsets were determined by flow cytometry using a whole blood lysis technique in the following groups: 28 PMR and 6 GCA patients before corticosteroid treatment, 20 PMR and 12 GCA patients in clinical remission with steroid treatment, 55 PMR patients in remission without steroid treatment, 17 rheumatoid arthritis (RA) patients before treatment, and 18 age-matched controls with noninflammatory conditions. Total white cell, lymphocyte, and platelet counts, hemoglobin, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were measured by routine techniques. Comparisons were made by the Student's t-test and the Mann-Whitney test. A MEDLINE database search for studies published between 1983 and 1997 was performed. RESULTS: Compared with noninflammatory controls, CD8+ T cells were not reduced before steroid treatment in patients with active PMR/GCA in proportion (P =.7) or absolute numbers (P =.1). Patients with active disease had significantly lower hemoglobin levels and higher platelet counts, CRP, and ESR than noninflammatory controls (P <.05). When compared with active RA, CD8+ T cells were not reduced in patients with active PMR in proportion (P =.5) or absolute numbers (P =.2). Between these two groups, RA patients were significantly younger (P =.003) and had lower ESR values (P =.003). We did not find significant differences between patients with active PMR/GCA and those in remission with steroid therapy, except for the lower hemoglobin levels and higher platelet count, CRP, and ESR in the active disease group (P <.05). The same results were found when patients with active disease were compared with PMR in remission and no longer on steroid therapy, the only significant differences were those parameters reflecting the acute phase response (hemoglobin levels, platelet count, CRP and ESR). CONCLUSIONS: This study does not confirm the previous findings that the proportion or number of circulating CD8+ T cells are reduced in patients with active PMR/GCA. The utility of the determination of CD8+ T cells for diagnostic and prognostic purpose should be evaluated in a large multicenter study.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Giant Cell Arteritis/immunology , Polymyalgia Rheumatica/immunology , C-Reactive Protein/analysis , CD8-Positive T-Lymphocytes/pathology , Flow Cytometry , Giant Cell Arteritis/drug therapy , Giant Cell Arteritis/pathology , Hematologic Tests , Humans , Polymyalgia Rheumatica/drug therapy , Polymyalgia Rheumatica/pathology , Prednisone/therapeutic use , Reference Values
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