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1.
Chemosphere ; 335: 139173, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37301515

RESUMEN

In the present work, a study about the electrochemical and photoelectrochemical degradation of an emerging pollutant using an Sb-doped SnO2 anode coated with a photocatalytic layer of BiPO4 has been performed. The electrochemical characterization of the material was carried out by means of linear sweep voltammetry, light-pulsed chronoamperometry and electrochemical impedance spectroscopy. These studies confirmed that the material is photoactive at intermediate potential values (around 2.5 V), and that the charge transfer resistance decreases in the presence of light. A positive effect of the illuminated area on the degradation degree of norfloxacin was observed: at 15.50 mA cm-2, the degradation rate was 83.37% in the absence of light, 92.24% with an illuminated area of 5.7 cm2, and it increased up to 98.82% with an illuminated area of 11.4 cm2. The kinetics of the process were evaluated, and the by-products of the degradation were identified by ion chromatography and HPLC. In the case of the mineralization degree, the effect of light is less significant, especially at higher current densities. The specific energy consumption of the process was lower in the photoelectrochemical experiments as compared to the experiments in dark conditions. At intermediate current densities (15.50 mA cm-2) a decrease in energy consumption of 53% was achieved by illuminating the electrode.


Asunto(s)
Compuestos de Estaño , Contaminantes Químicos del Agua , Oxidación-Reducción , Compuestos de Estaño/química , Titanio/química , Contaminantes Químicos del Agua/química , Electrodos , Cerámica
2.
Chemosphere ; 313: 137518, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36495980

RESUMEN

Advanced Oxidation Processes have been proven to be an efficient way to remove organic pollutants from wastewaters. In this work, a ceramic electrode of Sb-SnO2 (BCE) with a layer of the photocatalytic material BiFeO3 (BFO-BCE), has been characterized electrochemically and further tested for norfloxacin photo-electrooxidation in the presence and absence of light. The electrode photoactivity was highly enhanced thanks to the presence of BiFeO3, as confirmed by Linear Sweep Voltammetry, chronoamperometry and potentiometry, and Electrochemical Impedance Spectroscopy. Additionally, working in galvanostatic mode, a high mineralization of norfloxacin was achieved after 240 min, reaching 62% at 25 mA cm-2 under light conditions. This value is comparatively higher than the 40% achieved with the BCE. The oxidation byproducts were followed by ionic chromatography and HPLC analysis, which also allowed us to propose an oxidation pathway of the norfloxacin molecule. Finally, some indicators of the reactor performance such as the Mineralization Current Efficiency and the specific energy consumption were analyzed, revealing that lower current densities (8.3 mA cm-2) led to higher current efficiencies, and that light improved both the current efficiency and energy consumption.


Asunto(s)
Norfloxacino , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Electrodos , Cerámica , Titanio/química
3.
Chemosphere ; 290: 133294, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34919908

RESUMEN

The present manuscript focuses on the study of the electrochemical oxidation of the insecticide Chlorfenvinphos (CVP). The assays were carried out under galvanostatic conditions using boron-doped diamond (BDD) and low-cost tin dioxide doped with antimony (Sb-doped SnO2) as anodes. The influence of the operating variables, such as applied current density, presence or absence of a cation-exchange membrane and concentration of supporting electrolyte, was discussed. The results revealed that the higher applied current density the higher degradation and mineralization of the insecticide for both anodes. The presence of the membrane and the highest concentration of Na2SO4 studied (0.1 M) as a supporting electrolyte benefited the oxidation process of CVP using the BDD electrode, while with the ceramic anode the elimination of CVP was lower under these experimental conditions. Although the BDD electrode showed the best performance, ceramic anodes appear as an interesting alternative as they were able to degrade CVP completely for the highest applied current density values. Toxicity tests revealed that the initial solution of CVP was more toxic than the samples treated with the ceramic electrode, while using the BDD electrode the toxicity of the sample increased.


Asunto(s)
Clorfenvinfos , Plaguicidas , Contaminantes Químicos del Agua , Diamante , Electrodos , Electrólisis , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
4.
J Environ Manage ; 268: 110710, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32510444

RESUMEN

The electrochemical oxidation of the antibiotic Norfloxacin (NOR) in chloride media on different anodic materials was studied at two different electrochemical reactors. The results were compared with those obtained in sulphate media. The anodes under study were a commercial boron-doped diamond (BBD) and two different ceramic electrodes based on tin oxide doped with antimony oxide in the presence (CuO) and absence (BCE) of copper oxide as sintering aid. The reactors employed were a one-compartment reactor (OCR) and a two-compartment one with a membrane separating both electrodes (EMR). The use of the membrane clearly enhanced both NOR degradation and TOC mineralization for all the anodic materials studied since some parallel reactions were avoided. Additionally, two different pathways for NOR oxidation were observed as a function of the reactor employed. The EMR also favoured the ionic by-products generation and the electrolyte dechlorination. NO3- increased with the oxidation power of the anode employed and it was also enhanced by the EMR use. Chloride media favours ceramic electrodes performance independently of the reactor employed as they did not generate an excess of oxidants as BDD did. The BCE electrode is an interesting alternative to BDD since although its oxidative power was lower, it presented similar current efficiency with lower energy consumption.


Asunto(s)
Contaminantes Químicos del Agua , Boro , Cerámica , Diamante , Electrodos , Oxidación-Reducción
5.
Chemosphere ; 249: 126178, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32087454

RESUMEN

Norfloxacin is employed as in veterinary and human medicine against gram-positive and gram-negative bacteria. Due to the ineffective treatment at the wastewater treatment plants it becomes an emergent pollutant. Electro-oxidation appears as an alternative to its effective mineralization. This work compares Norfloxacin electro-oxidation on different anodic materials: two ceramic electrodes (both based on SnO2 + Sb2O3 with and without CuO, named as CuO and BCE, respectively) and a boron doped diamond (BDD). First, the anodes were characterized by cyclic voltammetry, revealing that NOR direct oxidation occurred at 1.30 V vs. Ag/AgCl. The higher the scan rate the higher both the current density and the anodic potential of the peak. This behavior was analyzed using the Randles-Sevcik equation to calculate the Norfloxacin diffusion coefficient in aqueous media, giving a value of D = 7.80 × 10-6 cm2 s-1 at 25 °C), which is close to the predicted value obtained using the Wilke-Chang correlation. The electrolysis experiments showed that both NOR and TOC decay increased with the applied current density, presenting a pseudo-first order kinetic. All the anodes tested achieved more than 90% NOR degradation at each current density. The CuO is not a good alternative to BCE because although it acts as a catalyst during the first use, it is lost from the anode surface in the subsequent uses. According to their oxidizing power, the anodes employed are ordered as follows: BDD > BCE > CuO.


Asunto(s)
Cobre/química , Norfloxacino/química , Contaminantes Químicos del Agua/química , Antibacterianos , Antimonio/química , Boro , Cerámica , Cloruros , Cloro , Diamante , Electrodos , Electrólisis , Bacterias Gramnegativas , Bacterias Grampositivas , Norfloxacino/análisis , Oxidación-Reducción , Compuestos de Estaño/química , Aguas Residuales , Contaminantes Químicos del Agua/análisis
6.
Rev Med Interne ; 39(10): 800-804, 2018 Oct.
Artículo en Francés | MEDLINE | ID: mdl-29627129

RESUMEN

Vascular malformations are poorly recognized constitutional anomalies which arises during early childhood. Several classifications tried to draw a distinction across the different entities. Recent advances in molecular biology have contributed to the update of their nosology. Syndromic vascular malformations are an example: while Klippel-Trenaunay syndrome, Proteus or CLOVES syndrome share many common features, understanding of pathological mechanism and specially the role of the PIK3/AKT/mTOR pathway enables us to rethink their classification. Then, some syndromes associated with overgrowth and vascular malformation have been grouped under a single term: "PIK3CA-related overgrowth spectrum" (PROS), and this group continues to grow. This new approach suggests new treatment options. Rapamycin, a PIK3/AKT/mTOR pathway inhibitor, demonstrated its efficiency for some forms of PROS. Targeted therapies such as PIK3 or mTOR selective inhibitor are still in a developmental phase and results are encouraging. This is an example of personalized medicine with significant therapeutic benefit for some patients. However, genotype relation with therapeutic efficiency must be clarified and physicians should pay attention to possible negative effects of these drugs, especially for young patients.


Asunto(s)
Anomalías Linfáticas/diagnóstico , Anomalías Linfáticas/terapia , Malformaciones Vasculares/diagnóstico , Malformaciones Vasculares/terapia , Venas/anomalías , Edad de Inicio , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Anomalías Linfáticas/complicaciones , Anomalías Linfáticas/epidemiología , Síndrome , Malformaciones Vasculares/complicaciones , Malformaciones Vasculares/epidemiología
7.
Support Care Cancer ; 25(8): 2455-2462, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28281052

RESUMEN

PURPOSE: Breast cancer-related lymphedema (BCRL) is a debilitating condition. The recommended treatment is based on decongestive lymphedema therapy (DLT) with two separate phases: a short-term intensive phase to reduce lymphedema volume and a long-term maintenance phase to stabilize it. Optimizing compression therapy and compliance during maintenance phase are key factors for long-term control of lymphedema. The primary objective of this pilot prospective open-label randomized study was to assess the benefit of a new auto-adjustable nighttime arm sleeve (MOBIDERM® Autofit) on lymphedema volume during the maintenance phase after the intensive phase. METHODS: Forty women with BRCL were consecutively enrolled and randomized (D0) for 1 month in 1:1 ratio either in night-use group: with MOBIDERM® Autofit (on top of a daytime compression hosiery), or in no night-use group: without MOBIDERM® Autofit (daytime hosiery alone). From Day 31 to Day 90, all patients were fitted with MOBIDERM® Autofit. Primary endpoint was lymphedema volume variation between Day 0 and Day 30. Secondary endpoints were compliance, quality of life (LYMQOL arm questionnaire), functional symptoms (heaviness, limb use limitation, pain), sleep quality, and safety. RESULTS: In ITT population, between Day 0 and Day 30, mean lymphedema volume increase was higher in no night-use group with 92.9 mL (i.e., 3.2%) than in night-use group with 46.7 mL (i.e., 1.80%), p = 0.757. Between Day 30 and Day 90, all patients fitted with MOBIDERM® Autofit, lymphedema volume remained stable in both groups. The device improved functional symptoms and function domain of the LYMQOL arm questionnaire. MOBIDERM® Autofit was worn overnight almost 85% of the nights. It was well accepted by the patients and no adverse reaction leading to permanent device discontinuation occurred. CONCLUSIONS: Our results suggest that MOBIDERM® Autofit offers clinical benefits during maintenance phase of lymphedema treatment and enhances patient's self-management.


Asunto(s)
Linfedema/terapia , Calidad de Vida/psicología , Medias de Compresión/estadística & datos numéricos , Extremidad Superior/patología , Anciano , Femenino , Humanos , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Autocuidado
8.
J Mal Vasc ; 38(1): 29-42, 2013 Feb.
Artículo en Francés | MEDLINE | ID: mdl-23312609

RESUMEN

THE QUALITY STANDARDS OF THE FRENCH SOCIETY OF VASCULAR MEDICINE FOR THE ULTRASONOGRAPHIC ASSESSMENT OF VASCULAR MALFORMATIONS ARE BASED ON THE TWO FOLLOWING REQUIREMENTS: Technical know-how: mastering the use of ultrasound devices and the method of examination. Medical know-how: ability to adapt the methods and scope of the examination to its clinical indication and purpose, and to rationally analyze and interpret its results. AIMS OF THE QUALITY STANDARDS: To describe an optimal method of examination in relation to the clinical question and hypothesis. To achieve consistent practice, methods, glossary, and reporting. To provide good practice reference points, and promote a high-quality process. ITEMS OF THE QUALITY STANDARDS: The three levels of examination; their clinical indications and goals. The reference standard examination (level 2), its variants according to clinical needs. The minimal content of the examination report; the letter to the referring physician (synthesis, conclusion and proposal for further investigation and/or therapeutic management). Commented glossary (anatomy, hemodynamics, semiology). Technical bases. Settings and use of ultrasound devices. Here, we discuss the methods of using ultrasonography for the assessment of peripheral vascular malformations and tumors.


Asunto(s)
Garantía de la Calidad de Atención de Salud , Ultrasonografía Doppler/normas , Malformaciones Vasculares/diagnóstico por imagen , Neoplasias Vasculares/diagnóstico por imagen , Brazo/irrigación sanguínea , Arterias/diagnóstico por imagen , Hemangioma/diagnóstico por imagen , Humanos , Pierna/irrigación sanguínea , Linfangioma/diagnóstico por imagen , Examen Físico/métodos , Examen Físico/normas , Ultrasonografía Doppler/instrumentación , Ultrasonografía Doppler/métodos , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Doppler en Color/normas , Ultrasonografía Doppler de Pulso/métodos , Ultrasonografía Doppler de Pulso/normas , Ultrasonografía Intervencional/normas , Malformaciones Vasculares/clasificación , Venas/diagnóstico por imagen , Trombosis de la Vena/diagnóstico por imagen
9.
Rev Esp Cardiol ; 50(12): 902-3, 1997 Dec.
Artículo en Español | MEDLINE | ID: mdl-9470455

RESUMEN

The paralysis of the left laryngeal nerve secondary to mitral valvular disease (Ortner's syndrome) is quite rare. Ortner believed that the paralysis was due to the compression of the nerve by the enlargement of the left atrium. Other authors have shown, by observation at operation, that this compression is produced between enlarged, tense pulmonary artery and the aorta at the ligamentum arteriosum. This complication has also been described in different cardiovascular pathologies which also have pulmonary hypertension. Cases have been described in the literature of vocal cord function recovery after a pulmonary hypertension decrease. We present a case of hoarseness secondary to the paralysis of the left recurrent laryngeal nerve within a context of a mitral periprosthetic insufficiency with severe pulmonary hypertension and its disappearance after the valvular change, coinciding with a significant artery pulmonary estimated pressure decrease, confirmed by cardiac Eco-Doppler.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Insuficiencia de la Válvula Mitral/complicaciones , Parálisis de los Pliegues Vocales/etiología , Ecocardiografía , Femenino , Ronquera/etiología , Humanos , Hipertensión Pulmonar/complicaciones , Persona de Mediana Edad , Válvula Mitral , Insuficiencia de la Válvula Mitral/diagnóstico , Insuficiencia de la Válvula Mitral/etiología , Síndrome
10.
J Clin Psychiatry ; 55 Suppl: 86-92, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7961537

RESUMEN

Often obsessive compulsive disorder (OCD) patients are labeled as treatment refractory when some first-line options have not been fully explored. Most patients should be encouraged to participate in behavior therapy, even when pharmacotherapy alone has been partially successful. Antiobsessional agents such as clomipramine, fluoxetine, and fluvoxamine should be considered first-line drugs. Their prescription for a sufficient time and at therapeutic doses is imperative. Enhancement strategies for a selected group of OCD patients include low-dose high-potency neuroleptics. In addition, clonazepam can be helpful in augmenting the response to a first-line drug. Results from controlled studies with lithium and buspirone have been disappointing. If most of these pharmacologic alternatives fail, MAOIs appear to be the next best choice. Since in the future most referrals for treatment-refractory OCD patients will emanate from nonpsychiatrists, following a systemic strategy in their evaluation and pharmacologic management is most important.


Asunto(s)
Trastorno Obsesivo Compulsivo/terapia , Antipsicóticos/uso terapéutico , Terapia Conductista , Clomipramina/uso terapéutico , Clonazepam/uso terapéutico , Terapia Combinada , Ensayos Clínicos Controlados como Asunto , Quimioterapia Combinada , Terapia Electroconvulsiva , Fluoxetina/uso terapéutico , Fluvoxamina/uso terapéutico , Humanos , Inhibidores de la Monoaminooxidasa/uso terapéutico , Trastorno Obsesivo Compulsivo/tratamiento farmacológico , Trastorno Obsesivo Compulsivo/psicología , Resultado del Tratamiento
12.
Oral Surg Oral Med Oral Pathol ; 60(6): 608-10, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3865132

RESUMEN

Seven patients with lichen planus of the oral mucosa (four with erosive and three with reticular types of the disease) were studied; they were treated with 500 mg of griseofulvin twice daily for 2 1/2 months. In no case was improvement observed; on the contrary, in four patients (two with erosive and two with reticular forms) the condition worsened.


Asunto(s)
Griseofulvina/uso terapéutico , Liquen Plano/tratamiento farmacológico , Enfermedades de la Boca/tratamiento farmacológico , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
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