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1.
J Environ Manage ; 320: 115769, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35944316

RESUMEN

This review aims to assess different technologies for the on-site treatment of hospital wastewater (HWW) to remove pharmaceutical compounds (PhCs) as sustances of emerging concern at a bench, pilot, and full scales from 2014 to 2020. Moreover, a rough characterisation of hospital effluents is presented. The main detected PhCs are antibiotics and psychiatric drugs, with concentrations up to 1.1 mg/L. On the one hand, regarding the presented technologies, membrane bioreactors (MBRs) are a good alternative for treating HWW with PhCs removal values higher than 80% in removing analgesics, anti-inflammatories, cardiovascular drugs, and some antibiotics. Moreover, this system has been scaled up to the pilot plant scale. However, some target compounds are still present in the treated effluent, such as psychiatric and contrast media drugs and recalcitrant antibiotics (erythromycin and sulfamethoxazole). On the other hand, ozonation effectively removes antibiotics found in the HWW (>93%), and some studies are carried out at the pilot plant scale. Even though, some families, such as the X-ray contrast media, are recalcitrant to ozone. Other advanced oxidation processes (AOPs), such as Fenton-like or UV treatments, seem very effective for removing pharmaceuticals, Antibiotic Resistance Bacteria (ARBs) and Antibiotic Resistance Genes (ARGs). However, they are not implanted at pilot plant or full scale as they usually consider extra reactants such as ozone, iron, or UV-light, making the scale-up of the processes a challenging task to treat high-loading wastewater. Thus, several examples of biological wastewater treatment methods combined with AOPs have been proposed as the better strategy to treat HWW with high removal of PhCs (generally over 98%) and ARGs/ARBs (below the detection limit) and lower spending on reactants. However, it still requires further development and optimisation of the integrated processes.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Antibacterianos , Medios de Contraste , Hospitales , Humanos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
2.
Proc Natl Acad Sci U S A ; 119(10): e2112397119, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35239443

RESUMEN

SignificanceThe modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein- and ß-arrestin (ßarr)-dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine.


Asunto(s)
Encéfalo/metabolismo , Dopamina/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Receptores de Ghrelina/metabolismo , Animales , Dopamina/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Masculino , Ratones , Ratones Noqueados , Receptores de Ghrelina/genética
3.
J Photochem Photobiol B ; 221: 112253, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34271411

RESUMEN

Biofilms formed by different bacterial species are likely to play key roles in photocatalytic resistance. This study aims to evaluate the efficacy of a photocatalytic immobilized nanotube system (TiO2-NT) (IS) and suspended nanoparticles (TiO2-NP) (SS) against mono- and dual-species biofilms developed by Gram-negative and Gram-positive strains. Two main factors were corroborated to significantly affect the biofilm resistance during photocatalytic inactivation, i.e., the biofilm-growth conditions and biofilm-forming surfaces. Gram-positive bacteria showed great photosensitivity when forming dual-species biofilms in comparison with the Gram-positive bacteria in single communities. When grown onto TiO2-NT (IS) surfaces for immobilized photocatalytic systems, mono- and dual-species biofilms did not exhibit differences in photocatalytic inactivation according to kinetic constant values (p > 0.05) but led to a reduction of ca. 3-4 log10. However, TiO2-NT (IS) surfaces did affect biofilm colonization as the growth of mono-species biofilms of Gram-negative and Gram-positive bacteria is significantly (p ≤ 0.05) favored compared to co-culturing; although, the photocatalytic inactivation rate did not show initial bacterial concentration dependence. The biofilm growth surface (which depends on the photocatalytic configuration) also favored resistance of mono-species biofilms of Gram-positive bacteria compared to that of Gram-negative in immobilized photocatalytic systems, but opposite behavior was confirmed with suspended TiO2 (p ≤ 0.05). Successful efficacy of immobilized TiO2 for inactivation of mono- and dual-species biofilms was accomplished, making it feasible to transfer this technology into real scenarios in water treatment and food processing.


Asunto(s)
Biopelículas/efectos de los fármacos , Titanio/química , Rayos Ultravioleta , Biopelículas/efectos de la radiación , Catálisis , Listeria monocytogenes/fisiología , Nanotubos/química , Salmonella typhimurium/fisiología , Titanio/toxicidad
4.
J Hazard Mater ; 372: 94-102, 2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29728280

RESUMEN

This study explores the enhancement of UV-C tertiary treatment by sulfate radical based Advanced Oxidation Processes (SR-AOPs), including photolytic activation of peroxymonosulfate (PMS) and persulfate (PS) and their photocatalytic activation using Fe(II). Their efficiency was assessed both for the inactivation of microorganisms and the removal or micropollutants (MPs) in real wastewater treatment plant effluents. Under the studied experimental range (UV-C dose 5.7-57 J/L; UV-C contact time 3 to 28 s), the photolysis of PMS and PS (0.01 mM) increased up to 25% the bacterial removal regarding to UV-C system. The photolytic activation of PMS led to the total inactivation of bacteria (≈ 5.70 log) with the highest UV-C dose (57 J/L). However, these conditions were insufficient to remove the MPs, being required oxidant's dosages of 5 mM to remove above 90% of carbamazepine, diclofenac, atenolol and triclosan. The best efficiencies were achieved by the combination of PMS or PS with Fe(II), leading to the total removal of the MPs using a low UV-C dosage (19 J/L), UV-C contact time (9 s) and reagent's dosages (0.5 mM). Finally, high mineralization was reached (>50%) with photocatalytic activation of PMS and PS even with low reagent's dosages.

5.
Sci Total Environ ; 630: 1216-1225, 2018 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-29554743

RESUMEN

The high chemical stability and the low biodegradability of a vast number of micropollutants (MPs) impede their correct treatment in urban wastewater treatment plants. In most cases, the chemical oxidation is the only way to abate them. Advanced Oxidation Processes (AOPs) have been experimentally proved as efficient in the removal of different micropollutants at lab-scale. However, there is not enough information about their application at full-scale. This manuscript reports the application of three different AOPs based on the addition of homogeneous oxidants [hydrogen peroxide, peroxymonosulfate (PMS) and persulfate anions (PS)], in the UV-C tertiary treatment of Estiviel wastewater treatment plant (Toledo, Spain) previously designed and installed in the facility for disinfection. AOPs based on the photolytic decomposition of oxidants have been demonstrated as more efficient than UV-C radiation alone on the removal of 25 different MPs using low dosages (0.05-0.5 mM) and very low UV-C contact time (4-18 s). Photolysis of PMS and H2O2 reached similar average MPs removal in all the range of oxidant dosages, obtaining the highest efficiency with 0.5 mM and 18 s of contact time (48 and 55% respectively). Nevertheless, PMS/UV-C reached slightly higher removal than H2O2/UV-C at low dosages. So, these treatments are selective to degrade the target compounds, obtaining different removal efficiencies for each compound regarding the oxidizing agent, dosages and UV-C contact time. In all the cases, H2O2/UV-C is more efficient than PMS/UV-C, comparing the ratio cost:efficiency (€/m3·order). Even H2O2/UV-C treatments are more efficient than UV-C alone. Thus, the addition of 0.5 mM of H2O2 compensates the increased of UV-C contact time and therefore the increase of electrical consumption, that it should be need to increase the removal of MPs by UV-C treatments alone.

6.
Photochem Photobiol Sci ; 16(11): 1690-1699, 2017 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-29034394

RESUMEN

Photocatalysis has a potential to become a cost effective industrial process for water cleaning. One of the most studied photocatalysts is titanium dioxide which, as a wide band gap semiconductor, requires ultraviolet (UV) light for its photoactivation. This is at the wavelengths where the efficiency of present-day light emitting diodes (LEDs) decreases rapidly, which presents a challenge in the use of UV-LEDs for commercially viable photocatalysis. There is also a need for accurate photocatalysis measurement of remediation rates of water-borne contaminants for determining optimum exposure doses in industrial applications. In response to these challenges, this paper describes a UV-LED based photocatalytic test reactor that provides a calibrated adjustable light source and pre-defined test conditions to remove as many sources of uncertainty in photocatalytic analysis as possible and thereby improve data reliability. The test reactor provides a selectable intensity of up to 1.9 kW m-2 at the photocatalyst surface. The comparability of the results is achieved through the use of pre-calibration and control electronics that minimize the largest sources of uncertainty; most notably variations in the intensity and directionality of the UV light emission of LEDs and in LED device heating.

8.
J Nanosci Nanotechnol ; 15(9): 6651-62, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26716224

RESUMEN

Titanium dioxide coatings were deposited on the surface of titanium foils by Thermal Plasma Spray (TPS) process. Three different TiO2 coatings were prepared using the commercial TiO2-P25 nanopowder and titanium isopropoxide precursor solution as feed-stocks. Structure and morphology of the TiO2-P25 powder and the plasma sprayed coatings were analyzed by X-ray diffraction (XRD), Raman spectroscopy, N2 adsorption-desorption isotherms, UV-visible spectroscopy and Scanning Electron Microscopy (SEM). XRD and Raman results indicate that the TiO2 coatings were composed of an anatase/rutile mixture that is conditioned by the suspension composition used to be sprayed. Coatings prepared from TiO2-P25 nanoparticles in water suspension (NW-P25) and titanium isopropoxide solution suspension (NSP-P25) are incorporated into the coatings without phase transformation and their anatase/rutile ratio percentage remains very similar to the starting TiO2-P25 powder. On the contrary, when titanium isopropoxide solution is used for spraying (SP), the amount of rutile increases in the final TiO2 coating. SEM analysis also reveals different microstructure morphology, coating thickness, density and porosity of the three TiO2 films that depend significantly on the type of feed-stock employed. Interestingly, we have observed the role of titanium isopropoxide in the formation of more porous and cohesive layers of TiO2. The NSP-P25 coating, prepared with a mix of titanium isopropoxide solution based on TiO2 nanoparticles, presents higher deposition efficiencies and higher coating thickness than the film prepared with nanoparticles suspended in water (NW-P25) or with titanium isopropoxide solutions (SP). This is due to the precursor solution is acting as the cement between TiO2 nanoparticles, improving the cohesive strength of the coating. In sum, NSP-P25 and NW-P25 coatings display a good photocatalytic potential, based on their light absorption properties and mechanical stability. Band gap of the nanoparticulated coatings displays a light absorption at wavelengths below 379 and 399 nm for NW-P25 and NSP-P25 respectively. On the contrary, the SP coating, despite to present lower band-gap value, has bad cohesive properties with surface crackings that makes it mechanically unstable. Therefore, mixtures of P25 nanoparticles with titanium isopropoxide as feed-stock materials can produce promising photocatalytic coatings.


Asunto(s)
Nanopartículas/química , Gases em Plasma/química , Titanio/química , Ensayo de Materiales , Propiedades de Superficie
9.
Water Sci Technol ; 68(5): 999-1003, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24037149

RESUMEN

Different TiO2 photoelectrodes have been characterized and tested for the photoelectrocatalytic oxidation of methanol. Particulate electrodes (TiO2/Ti and TiO2/ITO) have been shown to notably favour charge-carrier transfer at the electrolyte interface while a thermal electrode (Ti) has been shown to favour charge-carrier separation when applying an electric potential bias according to cyclic voltammetry technique, as a consequence of differences in TiO2 surface between particulate and thermal electrodes. Particulate electrodes lead to a higher photoelectrocatalytic activity for methanol oxidation compared to that of the thermal electrode, probably due to the pure-rutile TiO2 phase composition of the latter and its lower surface area. TiO2/Ti electrode has been shown to be the most effective photoelectrode tested for methanol oxidation since its activity was improved by the combination of the particulate TiO2 layer and the high electrical conductivity of the support. Generally, photocurrent density measured in the photoelectrochemical cell seems to correlate with activity, whereas this correlation is not observed when using a larger photoelectrocatalytic reactor. In contrast, the activity obtained for the scaled-up electrode is found to be similar in terms of surface kinetic constant to that obtained at laboratory scale.


Asunto(s)
Electroquímica/métodos , Fotoquímica/métodos , Titanio/química , Purificación del Agua/métodos , Electrodos
11.
Pediatr Diabetes ; 8(6): 369-73, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18036062

RESUMEN

OBJECTIVES: To determine the incidence and prevalence of type 1 diabetes in children younger than 15 yr in the Autonomous Community of Castilla-Leon (Spain). RESEARCH DESIGN AND METHODS: All type 1 diabetic cases with onset at <15 yr of age were recorded during 2003-2004. Identified case subjects were ascertained from several sources and the capture-recapture method was used to estimate the completeness of ascertainment. For prevalence, all patients younger than 15 yr with type 1 diabetes at the beginning and at the end of the study were identified. RESULTS: Over the study period, 130 children aged 0-14 yr were diagnosed with type 1 diabetes. The average observed incidence of type 1 diabetes in this population was 22.22/100 000/yr (95% CI 14.57-29.81). Age-standardized incidence was 22.01/100 000/yr (95% CI 18.18-25.83). The highest incidence was observed in the 5-9 yr age-group (32.45/100 000/yr, 95% CI 24.31-40.59). The prevalence at the beginning and at the end of the study was 1.01/1000 and 1.18/1000, respectively. CONCLUSION: Castilla-Leon appears to have one of the highest incidences of childhood type 1 diabetes in Spain, with recent incidence approaching those of some northern European countries.


Asunto(s)
Diabetes Mellitus Tipo 1/epidemiología , Adolescente , Distribución por Edad , Niño , Preescolar , Femenino , Humanos , Incidencia , Masculino , Prevalencia , España/epidemiología
12.
Water Res ; 40(4): 833-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16434074

RESUMEN

Over the last years, many research groups have developed supported TiO2-based materials in order to improve the engineering applications of photocatalytic technologies. However, not many attempts have been made to evaluate the optical behavior of these materials. This work focuses on the study of the photonic efficiencies of silica-supported TiO2 photocatalysts following the photodegradation of dichloroacetic acid (DCA) as model compound. Catalysts with different types of silica support and titania loadings were tested and their activity was found to be in correlation with the results of the clusters size distribution of the TiO2 nanocrystals. The photonic efficiency of the supported photocatalysts depends extremely on the optical density of the solid suspensions. Influence of the textural properties of the support and the titania loading on the optical density as well as on the photonic efficiency of the materials are discussed. The dependence of the absorption of radiation by the suspension on the catalyst concentration is also analyzed.


Asunto(s)
Colorantes/química , Titanio/química , Eliminación de Residuos Líquidos/métodos , Residuos Industriales , Ensayo de Materiales , Óptica y Fotónica , Fotoquímica , Dióxido de Silicio/química
13.
Gastroenterol Hepatol ; 28(8): 437-40, 2005 Oct.
Artículo en Español | MEDLINE | ID: mdl-16185576

RESUMEN

BACKGROUND: Anti-transglutaminase antibodies have been proposed as a useful tool in the diagnosis and follow-up of celiac disease. AIM: To compare anti-transglutaminase antibodies with the classical antibodies used to diagnose celiac disease. MATERIAL AND METHOD: Patients who underwent duodenal biopsy for suspected celiac disease were selected if they had the following serum antibody samples: antiendomysial IgA, anti-transglutaminase IgA, antigliadin IgG, and antigliadin IgA. A diagnostic value of each of these antibodies was established according to the final diagnosis, taking the duodenal biopsy as the reference. RESULTS: One hundred twenty-two patients with duodenal biopsy and serologic markers for celiac disease were selected. Thirty-six patients were children (< 14 years-old) and 86 were adults. A diagnosis of celiac disease was made in 41 patients (26 children and 15 adults). Of the 15 adults, only 2 (13%) presented typical malabsorption syndrome. The sensitivity and specificity of anti-transglutaminase antibodies was 100% and 98% respectively compared with values of 97% and 98% for antiendomysial IgA, 85% and 97% for antigliadin IgA, and 97% and 92% for antigliadin IgG antibodies. CONCLUSIONS: The diagnostic value of anti-transglutaminase antibodies is high in celiac disease. These antibodies may be useful as a screening test to select candidates for duodenal biopsy.


Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Enfermedad Celíaca/diagnóstico , Proteínas de Unión al GTP/inmunología , Inmunoglobulina A/inmunología , Transglutaminasas/inmunología , Adulto , Especificidad de Anticuerpos , Atrofia , Biopsia , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/patología , Niño , Preescolar , Duodeno/patología , Femenino , Gliadina/inmunología , Humanos , Hiperplasia , Inmunoglobulina G/inmunología , Lactante , Masculino , Persona de Mediana Edad , Fibras Musculares Esqueléticas/inmunología , Fibras Musculares Esqueléticas/ultraestructura , Valor Predictivo de las Pruebas , Proteína Glutamina Gamma Glutamiltransferasa 2 , Sensibilidad y Especificidad
15.
Bioorg Med Chem ; 7(12): 3011-24, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10658608

RESUMEN

Cysteine farnesylation at the carboxylate terminal tetrapeptide CAAX of Ras protein is catalyzed by farnesyltransferase. This lipid modification is necessary for regulatory function of both normal and oncogenic Ras. The high frequency of Ras mutation in human cancers has prompted an intensive study on finding ways of controlling oncogenic Ras function. Inhibition of farnesyltransferase is among the most sought after targets for cancer chemotherapy. We report here the design, synthesis and biological characterization of a series of peptidomimetics as farnesyltransferase inhibitors. These compounds are extremely potent towards farnesyltransferase with IC50 values ranging from subnanomolar to low nanomolar concentrations. They have a high selectivity for farnesyltransferase over the closely related geranylgeranyltransferase-I. Structure-activity relationship studies demonstrated that a properly positioned hydrophobic group significantly enhanced inhibition potency, reflecting an improved complementarity to the large hydrophobic pocket in the CAAX binding site.


Asunto(s)
Transferasas Alquil y Aril/antagonistas & inhibidores , Transferasas Alquil y Aril/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Oligopéptidos/síntesis química , Oligopéptidos/farmacología , Sitios de Unión , Línea Celular , Diseño de Fármacos , Inhibidores Enzimáticos/química , Farnesiltransferasa , Humanos , Espectroscopía de Resonancia Magnética , Sondas Moleculares , Oligopéptidos/química , Proteínas ras/metabolismo
17.
An Esp Pediatr ; 27(5): 390-2, 1987 Nov.
Artículo en Español | MEDLINE | ID: mdl-3326445

RESUMEN

The purpose of this report is to describe a seven-years-old patient with an idiopathic perforation of the common bile duct. This disorder is more frequent in the first weeks of life, and the clinical features are not well known. Properly treated, the majority of infants survive without sequelae. Furthermore, a review of the literature is made.


Asunto(s)
Enfermedades del Conducto Colédoco/cirugía , Niño , Colangiografía , Enfermedades del Conducto Colédoco/diagnóstico , Humanos , Masculino , Rotura Espontánea/cirugía , Ultrasonografía
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