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1.
J Environ Manage ; 254: 109832, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31733480

RESUMEN

The chemical evolution of brines resulting from an inactive phosphogypsum pond derived of fertilizer industry located in Huelva (Spain, SW Europe) has been studied based on a weekly sampling from 2014 to 2017. Long-range time variation of metals and ions concentrations in brines are expected to depend on environmental parameters such as rainfall and evaporation. The results show that brines are enriched in F- (1.7-2.0 g/l), Cl- (13-24 g/l), SO42- (7.2-9.3 g/l), V (70-128 mg/l) and U (55-98 mg/l). A great variation of chemical concentrations has been found, due to dilution, recharge and evaporation processes. Most of the elements show peak concentrations in summer, coinciding with the lowest pH values (<1), high conductivity (>133 mS/cm), and high evaporation rates as expected. Nonetheless, F- shows an opposite behaviour, varying its concentrations between 0.9 g/l in summer and 3.7 g/l in the rainy season. According to the results, a future restoration plan for PG ponds should include the removal of brines and layered salts during summer in order to avoid the annual generation of brines and their impact on the environment.


Asunto(s)
Estanques , Contaminantes Químicos del Agua , Sulfato de Calcio , Europa (Continente) , Fósforo , Sales (Química) , España
2.
Artículo en Inglés | MEDLINE | ID: mdl-31160286

RESUMEN

We studied the molecular mechanisms involved in the postantibiotic effect of the fluoroquinolones levofloxacin and moxifloxacin in Streptococcus pneumoniae Wild-type strain R6 had postantibiotic effects of 2.05 ± 0.10 h (mean ± standard deviation [SD]) and 3.23 ± 0.45 h at 2.5× and 10× MIC of levofloxacin, respectively. Moxifloxacin exhibited lower effects of 0.87 ± 0.1 and 2.41 ± 0.29 h at 2.5× and 10× MIC, respectively. Fluoroquinolone-induced chromosome fragmentation was measured at equivalent postantibiotic effects for levofloxacin (2.5× MIC) and moxifloxacin (10× MIC). After 2 h of drug removal, reductions were approximately 7-fold for levofloxacin and 3-fold for moxifloxacin, without further decreases at later times. Variations in reactive oxygen species production were detected after 4 to 6 h of drug withdrawals, with decreases ≥400-fold for levofloxacin and ≥800-fold for moxifloxacin at 6 h. In accordance, after 4 to 6 h of drug withdrawal, the levofloxacin-induced upregulation of the fatCDEB operon, introducing iron in the bacteria, decreased up to 2- to 3-fold, and the moxifloxacin-induced upregulation of several genes involved in the production of pyruvate was reduced 3- to 7-fold. In accordance, lower postantibiotic effects (up to 1 h) were observed in strain R6 ΔspxB, lacking the main enzyme involved in oxygen peroxide production, than in R6. Although no change in the recovery of chromosome fragmentation was observed between R6 and R6 ΔspxB, 3.5 × 103-fold lower reactive oxygen species production was observed in R6 ΔspxB, without changes after drug removal. These results show that reactive oxygen species are the main factors directing the postantibiotic effect of levofloxacin and moxifloxacin in S. pneumoniae.


Asunto(s)
Fluoroquinolonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/metabolismo , División del ADN/efectos de los fármacos , Levofloxacino/farmacología , Pruebas de Sensibilidad Microbiana , Moxifloxacino/farmacología
3.
Antimicrob Agents Chemother ; 60(1): 409-17, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26525786

RESUMEN

We studied the transcriptomic response of Streptococcus pneumoniae to the fluoroquinolone moxifloxacin at a concentration that inhibits DNA gyrase. Treatment of the wild-type strain R6, at a concentration of 10× the MIC, triggered a response involving 132 genes after 30 min of treatment. Genes from several metabolic pathways involved in the production of pyruvate were upregulated. These included 3 glycolytic enzymes, which ultimately convert fructose 6-phosphate to pyruvate, and 2 enzymes that funnel phosphate sugars into the glycolytic pathway. In addition, acetyl coenzyme A (acetyl-CoA) carboxylase was downregulated, likely leading to an increase in acetyl-CoA. When coupled with an upregulation in formate acetyltransferase, an increase in acetyl-CoA would raise the production of pyruvate. Since pyruvate is converted by pyruvate oxidase (SpxB) into hydrogen peroxide (H2O2), an increase in pyruvate would augment intracellular H2O2. Here, we confirm a 21-fold increase in the production of H2O2 and a 55-fold increase in the amount of hydroxyl radical in cultures treated during 4 h with moxifloxacin. This increase in hydroxyl radical through the Fenton reaction would damage DNA, lipids, and proteins. These reactive oxygen species contributed to the lethality of the drug, a conclusion supported by the observed protective effects of an SpxB deletion. These results support the model whereby fluoroquinolones cause redox alterations. The transcriptional response of S. pneumoniae to moxifloxacin is compared with the response to levofloxacin, an inhibitor of topoisomerase IV. Levofloxacin triggers the transcriptional activation of iron transport genes and also enhances the Fenton reaction.


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/genética , Fluoroquinolonas/farmacología , Regulación Bacteriana de la Expresión Génica , Peróxido de Hidrógeno/metabolismo , Streptococcus pneumoniae/efectos de los fármacos , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Acetiltransferasas/genética , Acetiltransferasas/metabolismo , Proteínas Bacterianas/metabolismo , Topoisomerasa de ADN IV/genética , Topoisomerasa de ADN IV/metabolismo , Farmacorresistencia Bacteriana Múltiple , Fructosafosfatos/metabolismo , Eliminación de Gen , Perfilación de la Expresión Génica , Ontología de Genes , Glucólisis/efectos de los fármacos , Glucólisis/genética , Hierro/metabolismo , Levofloxacino/farmacología , Pruebas de Sensibilidad Microbiana , Anotación de Secuencia Molecular , Moxifloxacino , Estrés Oxidativo/efectos de los fármacos , Piruvato Oxidasa/genética , Piruvato Oxidasa/metabolismo , Ácido Pirúvico/metabolismo , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/metabolismo , Transcripción Genética
4.
Br J Nutr ; 115(12): 2114-21, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27087233

RESUMEN

An obesity paradox has been proposed in many conditions including HIV. Studies conducted to investigate obesity and its effect on HIV disease progression have been inconclusive and are lacking for African settings. This study investigated the relationship between overweight/obesity (BMI≥25 kg/m2) and HIV disease progression in HIV+ asymptomatic adults not on antiretroviral treatment (ART) in Botswana over 18 months. A cohort study in asymptomatic, ART-naïve, HIV+ adults included 217 participants, 139 with BMI of 18·0-24·9 kg/m2 and seventy-eight participants with BMI≥25 kg/m2. The primary outcome was time to event (≥25 % decrease in cluster of differentiation 4 (CD4) cell count) during 18 months of follow-up; secondary outcomes were time to event of CD4 cell count<250 cells/µl and AIDS-defining conditions. Proportional survival hazard models were used to compare hazard ratios (HR) on time to events of HIV disease progression over 18 months. Higher baseline BMI was associated with significantly lower risk of an AIDS-defining condition during the follow-up (HR 0·218; 95 % CI 0·068, 0·701; P=0·011). Higher fat mass at baseline was also significantly associated with decreased risk of AIDS-defining conditions during the follow-up (HR 0·855; 95 % CI 0·741, 0·987; P=0·033) and the combined outcome of having CD4 cell count≤250/µl and AIDS-defining conditions, whichever occurred earlier (HR 0·918; 95 % CI 0·847, 0·994; P=0·036). All models were adjusted for covariates. Higher BMI and fat mass among the HIV-infected, ART-naïve participants were associated with slower disease progression. Mechanistic research is needed to evaluate the association between BMI, fat mass and HIV disease progression.


Asunto(s)
Tejido Adiposo/metabolismo , Composición Corporal , Índice de Masa Corporal , Progresión de la Enfermedad , Infecciones por VIH/complicaciones , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/prevención & control , Adulto , Fármacos Anti-VIH , Botswana , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Humanos , Masculino , Obesidad/complicaciones , Modelos de Riesgos Proporcionales , Carga Viral
5.
J Environ Sci (China) ; 42: 246-258, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27090717

RESUMEN

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution, reduced costs and improved efficiency of technologies. Under the European Union (EU) energy directive, biomass is a suitable renewable source. The aim of this study was to experimentally quantify and characterize the emission of particulate matter (PM2.5) resulting from the combustion of two biomass fuels (chipped residual biomass from pine and eucalypt), in a pilot-scale bubbling fluidized bed (BFB) combustor under distinct operating conditions. The variables evaluated were the stoichiometry and, in the case of eucalypt, the leaching of the fuel. The CO and PM2.5 emission factors were lower when the stoichiometry used in the experiments was higher (0.33±0.1 g CO/kg and 16.8±1.0 mg PM2.5/kg, dry gases). The treatment of the fuel by leaching before its combustion has shown to promote higher PM2.5 emissions (55.2±2.5 mg/kg, as burned). Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass, while carbonate (CO3(2-)) accounted for between 2.3 and 8.5 wt.%. The particulate mass was mainly composed of inorganic matter (71% to 86% of the PM2.5 mass). Compared to residential stoves, BFB combustion generated very high mass fractions of inorganic elements. Chloride was the water soluble ion in higher concentration in the PM2.5 emitted by the combustion of eucalypt, while calcium was the dominant water soluble ion in the case of pine.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Eucalyptus , Incineración/métodos , Pinus
6.
Opt Express ; 23(3): 3751-61, 2015 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-25836227

RESUMEN

We report on the realization and characterization of two different designs for resonant THz cavities, based on wire-grid polarizers as input/output couplers, and injected by a continuous-wave quantum cascade laser (QCL) emitting at 2.55 THz. A comparison between the measured resonators parameters and the expected theoretical values is reported. With achieved quality factor Q ≈ 2.5 × 10(5), these cavities show resonant peaks as narrow as few MHz, comparable with the typical Doppler linewidth of THz molecular transitions and slightly broader than the free-running QCL emission spectrum. The effects of the optical feedback from one cavity to the QCL are examined by using the other cavity as a frequency reference.

7.
Talanta ; 271: 125726, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38316076

RESUMEN

Oncostatin M (OSM) is an interleukin-6 (IL-6) member family cytokine implicated in the pathogenesis of chronic diseases including inflammatory bowel disease (IBD). OSM is a novel diagnostic biomarker over-expressed in the serum of IBD patients. This paper reports on the first electrochemical OSM immunosensor, developed using a multistep fabrication process aimed at covalently immobilizing OSM antibodies on a mixed self-assembled monolayer coated gold working electrode. Cyclic voltammetry, atomic force microscopy (AFM), IR spectroscopy and optical characterizations were used to validate the sensor functionalization protocol. Electrochemical impedance spectroscopy (EIS) measurements were performed to assess the reliability of the immunosensor preparation and to verify the antibody-antigen complexes formation. The label-free immunosensor showed high sensitivity identifying OSM at clinically relevant concentrations (37-1000 pg mL-1) with low detection limit of 2.86 pg mL-1. Both sensitivity and selectivity of the proposed immunosensor were also demonstrated in human serum in the presence of interfering biomarkers, making it an innovative potential platform for the OSM biomarker detection in IBD patients' serum.


Asunto(s)
Técnicas Biosensibles , Enfermedades Inflamatorias del Intestino , Humanos , Técnicas Biosensibles/métodos , Oncostatina M , Reproducibilidad de los Resultados , Anticuerpos Inmovilizados/química , Inmunoensayo/métodos , Biomarcadores , Enfermedades Inflamatorias del Intestino/diagnóstico
8.
Chemosphere ; 340: 139870, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37633612

RESUMEN

Worldwide coal is still used for household heating purposes not only because it is available and cheap but also due to behavioural issues. Regional variability in fuels and combustion appliances make accurate emission estimates from this source hard to achieve. In the present study, gaseous (CO, VOCs, SO2 and NOX) and particulate matter (TSP) emission factors (EFs) were determined for Spanish household coal combustion covering three commercial coals and distinct combustion stages and mimicking usage patterns in real households. TSP samples were analysed to determine water-soluble inorganic ions, metal(loid)s, and organic and elemental carbon (OC and EC). Additionally, the morphology of the emitted particles was also characterised. CO (3.43-169 g kg-1), NOX (1.29-6.00 g kg-1) and SO2 (8.96-22.3 g kg-1) EFs showed no trend regarding the combustion stage or coal type tested. On the other hand, VOC, TSP and EC EFs were higher for the ignition/devolatilisation combustion stage, regardless of the fuel tested. TSP EFs (0.085-1.08 g kg-1) increased with increasing coal volatile matter while the opposite trend was recorded for VOC emissions (0.045-3.39 gC kg-1). TSP carbonaceous matter was dominated by EC while OC represented a small fraction of the particulate mass emitted (less than 8 %wt.). Inorganic compounds composed an important fraction of the TSP samples. Sulphate particulate mass fractions (8.66-22.9 %wt.) appeared to increase with coal S-content. Coal combustion released particles with diverse morphologies, including silicate-rich particles, ferro- and glassy-spheres. This study provides novel emission factors to update emission inventories of residential coal combustion. Additionally, detailed chemical profiles were obtained for source apportionment.


Asunto(s)
Compuestos Orgánicos Volátiles , Carbono , Carbón Mineral , Polvo , Gases
9.
J Clin Microbiol ; 50(12): 4047-53, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23052300

RESUMEN

Streptococcus pneumoniae plays an important role in causing acute exacerbations in patients with chronic respiratory disease. However, few data are available regarding pneumococcal persistence in adult patients with chronic respiratory diseases. Fifty pneumococci recovered from sputum samples (1995 to 2010) from 13 adult patients with ≥ 3 episodes of acute exacerbation or pneumonia, with the same serotype and pulsed-field gel electrophoresis (PFGE) pattern, were studied. Multilocus sequence typing (MLST) loci, penicillin-binding protein (PBP) genes (pbp2x, pbp1a, pbp2b), and the quinolone-resistant determining regions (QRDRs) of parC, parE, and gyrA were PCR amplified and sequenced. The average time between the first and last episode was 582 days (standard deviation [SD], ± 362). All but two patients received multiple courses of ß-lactam treatment, and all persistent strains were resistant to penicillin; however, the PBP sequences were stable over time apart from one variable nucleotide in pbp2x, observed among pneumococci isolated from three patients. In contrast, 7/11 patients treated with fluoroquinolones had fluoroquinolone-resistant pneumococci. In three patients, the initially fluoroquinolone-susceptible strain developed resistance after fluoroquinolone therapy, and in the remaining four patients, the persistent strain was fluoroquinolone resistant from the first episode. QRDR changes involved in fluoroquinolone resistance were frequently observed in persistent strains after fluoroquinolone treatment; however, the PBP sequences and MLST genotypes of these strains were stable over time.


Asunto(s)
Portador Sano/epidemiología , Infecciones Neumocócicas/epidemiología , Enfermedades Respiratorias/complicaciones , Streptococcus pneumoniae/aislamiento & purificación , Adulto , Anciano , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Proteínas Bacterianas/genética , Enfermedad Crónica , Dermatoglifia del ADN , Farmacorresistencia Bacteriana , Electroforesis en Gel de Campo Pulsado , Femenino , Fluoroquinolonas/farmacología , Fluoroquinolonas/uso terapéutico , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Esputo/microbiología , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genética , beta-Lactamas/farmacología , beta-Lactamas/uso terapéutico
10.
Int J Obes (Lond) ; 36(8): 1032-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21986708

RESUMEN

BACKGROUND/OBJECTIVES: Serum amyloid A (SAA) is an acute-phase protein that has been recently correlated with obesity and insulin resistance. Therefore, we first examined whether human recombinant SAA (rSAA) could affect the proliferation, differentiation and metabolism of 3T3-L1 preadipocytes. DESIGN: Preadipocytes were treated with rSAA and analyzed for changes in viability and [³H-methyl]-thymidine incorporation as well as cell cycle perturbations using flow cytometry analysis. The mRNA expression profiles of adipogenic factors during the differentiation protocol were also analyzed using real-time PCR. After differentiation, 2-deoxy-[1,2-³H]-glucose uptake and glycerol release were evaluated. RESULTS: rSAA treatment caused a 2.6-fold increase in cell proliferation, which was consistent with the results from flow cytometry showing that rSAA treatment augmented the percentage of cells in the S phase (60.9±0.54%) compared with the control cells (39.8±2.2%, (***) P<0.001). The rSAA-induced cell proliferation was mediated by the ERK1/2 signaling pathway, which was assessed by pretreatment with the inhibitor PD98059. However, the exposure of 3T3-L1 cells to rSAA during the differentiation process resulted in attenuated adipogenesis and decreased expression of adipogenesis-related factors. During the first 72 h of differentiation, rSAA inhibited the differentiation process by altering the mRNA expression kinetics of adipogenic transcription factors and proteins, such as PPARγ2 (peroxisome proliferator-activated receptor γ 2), C/EBPß (CCAAT/enhancer-binding protein ß) and GLUT4. rSAA prevented the intracellular accumulation of lipids and, in fully differentiated cells, increased lipolysis and prevented 2-deoxy-[1,2-³H]-glucose uptake, which favors insulin resistance. Additionally, rSAA stimulated the secretion of proinflammatory cytokines interleukin 6 and tumor necrosis factor α, and upregulated SAA3 mRNA expression during adipogenesis. CONCLUSIONS: We showed that rSAA enhanced proliferation and inhibited differentiation in 3T3-L1 preadipocytes and altered insulin sensitivity in differentiated cells. These results highlight the complex role of SAA in the adipogenic process and support a direct link between obesity and its co-morbidities such as type II diabetes.


Asunto(s)
Células 3T3-L1/metabolismo , Adipocitos/metabolismo , Desoxiglucosa/metabolismo , Resistencia a la Insulina , ARN Mensajero/metabolismo , Proteína Amiloide A Sérica/metabolismo , Animales , Diferenciación Celular/genética , Proliferación Celular , Citometría de Flujo , Humanos , Resistencia a la Insulina/genética , Péptidos y Proteínas de Señalización Intercelular , Ratones , Ratones Obesos , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteína Amiloide A Sérica/genética , Regulación hacia Arriba
11.
Clin Exp Immunol ; 163(3): 362-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21175596

RESUMEN

Serum amyloid A (SAA) levels are elevated highly in acute phase response and elevated slightly and persistently in chronic diseases such as rheumatoid arthritis and diabetes. Given that fibroblasts exert profound effects on progression of inflammatory chronic diseases, the aim of this study was to investigate the response of fibroblasts to SAA. A dose-dependent increase in O(2) (-) levels was observed by treatment of fibroblasts with SAA (r = 0·99 and P ≤ 0·001). In addition, the expression of p47-phox was up-regulated by SAA (P < 0·001) and diphenyliodonium (DPI), a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, reduced the release of O(2) (-) by 50%. Also, SAA raised fibroblast proliferation (P < 0·001) and this effect was completely abolished by the addition of anti-oxidants (P < 0·001). These findings support the notion that, in chronic inflammatory sites, SAA activated fibroblast proliferation and ROS production.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Fibroblastos/citología , Fibroblastos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína Amiloide A Sérica/farmacología , Animales , Antioxidantes/farmacología , Compuestos de Bifenilo/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Fibroblastos/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Ratones , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/genética , Compuestos Onio/farmacología , Células 3T3 Swiss
12.
HIV Med ; 12(2): 78-86, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20500231

RESUMEN

BACKGROUND: The pathogenesis of HIV/hepatitis C virus (HCV) coinfection is poorly understood. We examined markers of oxidative stress, plasma antioxidants and liver disease in HIV/HCV-coinfected and HIV-monoinfected adults. METHODS: Demographics, medical history, and proof of infection with HIV, hepatitis A virus (HAV), hepatitis B virus (HBV) and HCV were obtained. HIV viral load, CD4 cell count, complete blood count (CBC), complete metabolic panel, lipid profile, and plasma concentrations of zinc, selenium, and vitamins A and E were determined. Malondialdehyde (MDA) and glutathione peroxidase concentrations were obtained as measures of oxidative stress. Aminotransferase to platelet ratio index (APRI) and fibrosis index (FIB-4) markers were calculated. RESULTS: Significant differences were found between HIV/HCV-coinfected and HIV-monoinfected participants in levels of alanine aminotransferase (ALT) (mean±standard deviation: 51.4±50.6 vs. 31.9±43.1 U/L, respectively; P=0.014), aspartate aminotransferase (AST) (56.2±40.9 vs. 34.4±30.2 U/L; P<0.001), APRI (0.52±0.37 vs. 0.255±0.145; P=0.0001), FIB-4 (1.64±.0.91 vs. 1.03±0.11; P=0.0015) and plasma albumin (3.74±0.65 vs. 3.94±0.52 g/dL; P=0.038). There were no significant differences in CD4 cell count, HIV viral load or antiretroviral therapy (ART) between groups. Mean MDA was significantly higher (1.897±0.835 vs. 1.344± 0.223 nmol/mL, respectively; P=0.006) and plasma antioxidant concentrations were significantly lower [vitamin A, 39.5 ± 14.1 vs. 52.4±16.2 µg/dL, respectively (P=0.0004); vitamin E, 8.29±2.1 vs. 9.89±4.5 µg/mL (P=0.043); zinc, 0.61±0.14 vs. 0.67±0.15 mg/L (P=0.016)] in the HIV/HCV-coinfected participants than in the HIV-monoinfected participants, and these differences remained significant after adjusting for age, gender, CD4 cell count, HIV viral load, injecting drug use and race. There were no significant differences in glutathione peroxidase concentration, selenium concentration, body mass index (BMI), alcohol use or tobacco use between groups. Glutathione peroxidase concentration significantly increased as liver disease advanced, as measured by APRI (ß=0.00118; P=0.0082) and FIB-4 (ß=0.0029; P=0.0177). Vitamin A concentration significantly decreased (ß=-0.00581; P=0.0417) as APRI increased. CONCLUSION: HIV/HCV coinfection is associated with increased oxidative stress and decreased plasma antioxidant concentrations compared with HIV monoinfection. Research is needed to determine whether antioxidant supplementation delays liver disease in HIV/HCV coinfection.


Asunto(s)
Hepatitis C/sangre , Hepatitis C/complicaciones , Estrés Oxidativo/fisiología , Abuso de Sustancias por Vía Intravenosa/sangre , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Antioxidantes/metabolismo , Recuento de Linfocito CD4 , Femenino , Florida , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Humanos , Masculino
13.
J Environ Monit ; 13(5): 1276-87, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21437327

RESUMEN

A long-term series (2001-2008) of chemical analysis of atmospheric particulate matter (PM(10) and PM(2.5)) collected in the city of Huelva (SW Spain) is considered in this study. The impact of emission plumes from one of the largest Cu-smelters in the world on air quality in the city of Huelva is evidenced by the high daily and hourly levels of As, other potentially toxic elements (e.g. Cu, Zn, Cd, Se, Bi, and Pb) in particulate matter, as well as the high levels of some gaseous pollutants (NO(2) and SO(2)). Mean arsenic levels in the PM10 fraction were higher than the target value set by European Directive 2004/107/EC (6 ngAs m(-3)) for 1(st) January 2013. Hourly peak concentrations of As and other metals and elements (Zn, Cu, P and Se) analyzed by PIXE can reach maximum hourly levels as high as 326 ngAs m(-3), 506 ngZn m(-3), 345 ngCu m(-3), 778 ngP m(-3) and 12 ngSe m(-3). The contribution of Cu-smelter emissions to ambient PM is quantified on an annual basis in 2.0-6.7 µg m(-3) and 1.8-4.2 µg m(-3) for PM(10) and PM(2.5), respectively. High resolution outputs of the HYSPLIT dispersion model show the geographical distribution of the As ambient levels into the emission plume, suggesting that the working regime of the Cu-smelter factory and the sea breeze circulation are the main factors controlling the impact of the Cu-smelter on the air quality of the city. The results of this work improve our understanding of the behaviour of industrial emission plumes and their impact on air quality of a city, where the population might be exposed to very high ambient concentrations of toxic metals during a few hours.


Asunto(s)
Contaminantes Atmosféricos/análisis , Cobre/análisis , Material Particulado/análisis , Contaminantes Atmosféricos/química , Ciudades , Cobre/química , Monitoreo del Ambiente , Residuos Industriales/análisis , Residuos Industriales/estadística & datos numéricos , Metalurgia/estadística & datos numéricos , Material Particulado/química , España
14.
Environ Pollut ; 274: 116268, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33545528

RESUMEN

Air pollution coming from industrial activities is a matter of interest since their emissions can seriously affect to the human health of nearby populations. A more detailed study about industrial emissions is required in order to discriminate different activities contributing to pollutant sources. In this sense, gaseous pollutants (NO2, SO2 and O3) and PM10 levels has been studied in a complex industrial area in the southwest of Spain (La Rabida and the nearby city of Huelva) during the period 1996-2017. Hourly, daily, monthly and annual variations of PM10 and gaseous pollutants concentrations point to the industrial activity as the main SO2 source. Furthermore, traffic and resuspension emissions contribute to the NO2 and PM10 levels, respectively. Results from chemical composition of PM10 at both sites during the period 2015-2017 are characterized by high concentrations of the crustal components derived from natural and local resuspension. Arsenic is found to be the main geochemical anomaly at La Rabida (annual mean of 7 ng m-3), exceeding the European annual target of 6 ng m-3, which supposes a risk for the nearby population. An emission source from Cu-smelter has been identified in La Rabida and Huelva. A second source corresponding to emissions from polymetallic sulfides handling in a port area has been described for the first time in La Rabida. In addition, arsenic speciation results have identified three different As impacts scenarios as a function of the dominant wind direction, the SO2 episodes and the As extraction efficiency: impact of the Cu-smelter, impact of the bulk polymetallic sulfides and a mixed impact of both sources.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Arsénico , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , España
15.
Sci Total Environ ; 777: 144579, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33677295

RESUMEN

The Guadalquivir Valley is one of three major O3 hotspots in Spain. An airborne and surface measurement campaign was carried out from July 9th to 11th, 2019 to quantify the local/regional O3 contributions using experimental approaches. Air quality and meteorology data from surface measurements, a microlight aircraft, a helium balloon, and remote sensing data (TROPOMI-NO2-ESA) were used to obtain the 3D distribution of O3 and various tracer pollutants. O3 accumulation over 2.5 days started with inputs from oceanic air masses transported inland by sea breezes, which drew O3 and its precursors from a local/regional origin to the northeastern end of the basin. The orographic-meteorological setting of the valley caused vertical recirculation of the air masses inside the valley that caused the accumulation by increasing regional background O3 concentration by 25-30 ppb. Furthermore, possible Mediterranean O3 contributions and additional vertical recirculation through the entrainment zone of the convective boundary layer also contributed. Using particulate matter finer than 2.5 µm (PM2.5), ultrafine particles (UFP), and black carbon (BC) as tracers of local sources, we calculated that local contributions increased regional O3 levels by 20 ppb inside specific pollution plumes transported by the breeze into the valley, and by 10 ppb during midday when flying over an area with abundant agricultural burning during the morning. Air masses that crossed the southern boundaries of the Betic system at mid-altitude (400-1850 m a.s.l.) on July 10th and 11th may have provided additional O3. Meanwhile, a decreasing trend at high altitudes (3000-5000 m a.s.l.) was observed, signifying that the impact of stratospheric O3 intrusion decreased during the campaign.

16.
J Prev Med Hyg ; 51(1): 37-43, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20853675

RESUMEN

Aquaculture is an enterprise in constant development, in particular relating to its effect on the environment and also the quality of its products. It represents a valid alternative to traditional fishing, facing the increasing demand for fish products. To guarantee to the consumer a product of high nutritional, organoleptic and hygienic quality, it is fundamental to monitor every phase of the fish farming industry, isolating the potential risk points. For this reason there has been a rapid evolution of productive technique, particularly in the technology, artificial reproduction and feed sectors. The aim of this research has been the monitoring of the evolution of certain microbial and nutritional quality indexes (total microbial counts and lipid analysis on suspensions of Rotifers and Artemia, used as live feed) in the larval phase of the productive cycle of the farm raised fish, in an intensive system. The study has shown an increment in the total microbial counts in the fish farming industry within the production of Rotifers and Artemia, more evident in the suspensions of Rotifers. In addition the study has demonstrated that the maintenance phase, in the enrichment protocol, can reduce the EPA and DHA content. The results confirm the importance of microbial and nutritional control of the live feeds before they get supplied to fish larvae.


Asunto(s)
Alimentación Animal/análisis , Artemia , Explotaciones Pesqueras/métodos , Rotíferos , Microbiología del Agua , Animales , Artemia/crecimiento & desarrollo , Recuento de Colonia Microbiana , Ácidos Grasos/análisis , Humanos , Larva , Valor Nutritivo , Rotíferos/crecimiento & desarrollo , Alimentos Marinos
17.
Sci Total Environ ; 714: 136891, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32018998

RESUMEN

Hydrogen fluoride (HF) is one of the most toxic gaseous compounds in air, the primary anthropogenic source of which is industrial activity, specifically fertilizer and waste. HF concentrations in an urban area (Huelva, SW Spain) related to a nearby major phosphogypsum (PG) deposit were measured by passive sampling during summer and winter months from 2014 to 2017 and high-resolution sampling during 2017 and 2017-2018 using an HF analyser. An HF geochemical anomaly was found in the PG pond with average concentrations of up to 19.1 µg/m3, and concentrations of up to 1.6 µg/m3 were exhibited in the nearest urban area. The concentrations were associated with the HF emissions from the PG deposit. Emission factors were calculated by field and laboratory experiments, and the brines exhibited the highest emission factor (2.7 kg/ha day). Several impacts of HF (>0.1 µg/m3) in the city were recorded throughout the year, occurring at noon in the summer and during fog events in the winter. Consequently, the PG system should be restored to protect the population living in Huelva from the impacts of HF emission.

18.
Radiat Res ; 171(4): 438-45, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19397444

RESUMEN

We studied the DNA fragmentation induced in human fibroblasts by iron-ion beams of two different energies: 115 MeV/nucleon and 414 MeV/nucleon. Experimental data were obtained in the fragment size range 1-5700 kbp; Monte Carlo simulations were performed with the PARTRAC code; data analysis was also performed through the Generalized Broken Stick (GBS) model. The comparison between experimental and simulated data for the number of fragments produced in two different size ranges, 1-23 kbp and 23-5700 kbp, gives a satisfactory agreement for both radiation qualities. The Monte Carlo simulations also allow the counting of fragments outside the experimental range: The number of fragments smaller than 1 kbp is large for both beams, although with a strong difference between the two cases. As a consequence, we can compute different RBEs depending on the size range considered for the fragment counting. The PARTRAC evaluation takes into account fragments of all sizes, while the evaluation from the experimental data considers only the fragments in the range of 1-5700 kbp. When the PARTRAC evaluation is restricted to this range, the agreement between experimental and computed RBE values is again good. When fragments smaller than 1 kbp are also considered, the RBE increases considerably, since gamma rays produce a small number of such fragments. The analysis performed with the GBS model proved to be quite sensitive to showing, with a phenomenological single parameter, variations in double-strand break (DSB) correlation.


Asunto(s)
Fragmentación del ADN , ADN/efectos de la radiación , Fibroblastos/efectos de la radiación , Iones , Hierro , Simulación por Computador , Daño del ADN , Relación Dosis-Respuesta en la Radiación , Humanos , Método de Montecarlo , Dosis de Radiación
19.
Environ Res ; 109(6): 671-81, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19501351

RESUMEN

In the South of Spain, major industrial estates (e.g. Huelva) exist alongside ecologically interesting zones (e.g. Doñana National Park). Between June 2005 and June 2006, PM10 and PM2.5 were measured, for total mass, organic carbon (OC) and elemental carbon (EC) chemical composition, at a station in an ecologically interesting area located near Doñana National Park and an urban background area with industrial influence. The mean OC concentration is higher in the urban background (3.5 microg m(-3)) than in the rural monitoring station (2.8 microg m(-3)) as a consequence of local emissions (e.g. traffic). A total of 82% of TC is OC in the rural station, while the urban background station reveals 70% and 73% of TC in the PM10 and PM2.5 mass, respectively. The study of air-mass origin and characterization of carbonaceous species in the course of simultaneous sampling in rural and urban background monitoring stations differentiated three long-range air-mass transports: a North-African dust outbreak, Atlantic Advection and Continental (N-NW) episodes, the origins of the first and last of which are more heavily influenced by the anthropogenic emissions from industrial estates located around the city of Huelva (Punta del Sebo and Nuevo Puerto). Higher values were measured for OC and EC in the study area during the North-African dust outbreak, similar to those obtained during the Continental episode (N-NW), which was clearly influenced by industrial emissions, followed by the Atlantic Advection episodes. The comparison of carbon species with air-mass origin can help to discriminate the origin and source of particulate matter, as well as to determine the urban impact on rural areas.


Asunto(s)
Contaminantes Atmosféricos/análisis , Carbono/análisis , Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Material Particulado/análisis , Industrias , Salud Rural , España , Salud Urbana , Viento
20.
Int J STD AIDS ; 19(6): 410-3, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18595880

RESUMEN

Blood lipids and high-sensitivity C-reactive protein (hsCRP) are used to assess cardiovascular disease (CVD) risk. We evaluated in a cross-sectional design the relationship of hsCRP to markers of liver function (aspartate and alanine transaminases [AST and ALT, respectively]), CVD risk factors and HIV-disease progression markers in 226 HIV-1 sero-positive drug users. hsCRP showed a significant inverse relationship with ALT and high-density lipoprotein, independent of age, gender, viral load, CD4 cell-count and antiretroviral (ARV) use, and was not significantly associated with HIV-disease progression markers. Serum markers of liver damage, AST and ALT, were associated with lower hsCRP, total cholesterol, low-density lipoproteins and triglycerides. Elevated liver enzymes (> or =40 IU/L) were predictive of hsCRP levels that are considered a low risk for CVD. In conclusion, hsCRP may not be a reliable marker of CVD risk in populations with HIV at-risk for elevated liver enzymes due to high hepatitis B virus/hepatitis C virus prevalence and ARV use.


Asunto(s)
Alanina Transaminasa/sangre , Fármacos Anti-VIH/uso terapéutico , Proteína C-Reactiva/análisis , Enfermedades Cardiovasculares/sangre , Infecciones por VIH/complicaciones , Fármacos Anti-VIH/farmacología , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , Estudios Transversales , Infecciones por VIH/patología , Seropositividad para VIH , Prevalencia , Factores de Riesgo
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