RESUMEN
Manganese oxides (MnxOy) are considered as a promising catalyst alternative to platinum in fuel cell applications. In fact, a proper catalyst is needed in order to facilitate the oxygen reduction reaction (ORR) at the cathode, and platinum is considered the best material due to its low overpotential for this reaction. Contrary to platinum, MnxOy is inexpensive, environmentally friendly and can be shaped into several nanostructures; furthermore, most of them show significant electro-catalytic performance. Several strategies have been carried out in order to increase their efficiency, by preparing light and high-surface area materials. In this framework, nanofibres are among the most promising nanostructures that can be used for this purpose. In this work, a study of the thermal, morphological and catalytic behavior of MnxOy nanofibres obtained through the electrospinning technique is proposed. Emphasis is given to the thermal evolution of the precursors, proposing a possible crystallization mechanism of the different manganese oxides obtained. It turns out that manganese oxide nanofibres exhibit good catalytic performance for the ORR, comparable to those obtained by using Pt-based catalysts.
RESUMEN
BACKGROUND: Bradykinin (BK) mediates acute allergic asthma and airway remodelling. Nuclear factor-kappa B (NF-kB) is potentially involved in BK B2 receptor (B2R) regulation. OBJECTIVE: In this observational cross-sectional study, B2R and NF-kB expression was evaluated in bronchial biopsies from mild asthmatics (after diluent/allergen challenge) and healthy controls, examining the role of NF-kB in B2R expression in primary human fibroblasts from normal and asthmatic subjects (HNBFb and HABFb). METHODS: B2R and NF-kB (total and nuclear) expression was analysed by immunohistochemistry in biopsies from 10 mild intermittent asthmatics (48 h after diluent/allergen challenge) and 10 controls undergoing bronchoscopy. B2R co-localization in 5B5(+) and αSMA(+) mesenchymal cells was studied by immunofluorescence/confocal microscopy, and B2R expression in HABFb/HNBFb incubated with interleukin (IL)-4/IL-13 with/without BK, and after NF-kB inhibitor, by Western blotting. RESULTS: Bronchial mucosa B2R and nuclear NF-kB expression was higher in asthmatics after diluent (B2R only) and allergen challenge than in controls (P < 0.05), while B2R and NF-kB (total and nuclear) increased after allergen compared with after diluent (P < 0.05). Allergen exposure increased B2R expression in 5B5(+) and αSMA(+) cells. Constitutive B2R protein expression was higher in HABFb than in HNBFb (P < 0.05) and increased in both cell types after IL-13 or IL-4/IL-13 and BK treatment. This increase was suppressed by a NF-kB inhibitor (P < 0.05). CONCLUSIONS & CLINICAL RELEVANCE: Bronchial B2R expression is constitutively elevated in allergic asthma and is further increased after allergen exposure together with NF-kB expression. NF-kB inhibitor blocked IL-4/IL-13-induced increase in B2R expression in cultured fibroblasts, suggesting a role as potential anti-asthma drug.
Asunto(s)
Asma/inmunología , Asma/metabolismo , Bronquios/metabolismo , Receptor de Bradiquinina B2/metabolismo , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Actinas/genética , Actinas/metabolismo , Adulto , Alérgenos/inmunología , Asma/diagnóstico , Asma/genética , Bradiquinina/metabolismo , Bronquios/inmunología , Bronquios/patología , Estudios Transversales , Femenino , Fibroblastos/metabolismo , Expresión Génica , Humanos , Inmunohistoquímica , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Masculino , FN-kappa B/metabolismo , Receptor de Bradiquinina B2/genética , Pruebas de Función Respiratoria , Mucosa Respiratoria/patología , Factores de Riesgo , Adulto JovenRESUMEN
Severe asthma (SA) is associated with neutrophil recruitment and T helper (TH )17 chemokine overexpression in bronchial biopsies. We aimed to evaluate IL-17A and IL-17F expression in nasal/bronchial lamina propria of atopic mild-to-severe asthmatics and controls in relation to neutrophilia and asthma exacerbations. Cryostat sections of nasal/bronchial biopsies obtained from 14 SA and 14 mild asthma (MA) stable atopic patients with rhinitis, and seven healthy controls were analyzed by immunohistochemistry for neutrophils, IL-17A and IL-17F expression. Atopic SA showed an increase in asthma exacerbations number, IL-17F and IL-17A expression in nasal/bronchial lamina propria compared to MA and controls, and a higher expression of bronchial neutrophils in SA compared to MA and controls. In all asthmatics, significant relationships were found between bronchial IL-17F and neutrophils/FEV1 , nasal IL-17F and bronchial neutrophil/IL-17 markers and between the latter and exacerbations, suggesting that nasal IL-17F might be informative on bronchial IL17-driven neutrophilia in atopic SA.
Asunto(s)
Asma/diagnóstico , Asma/metabolismo , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/metabolismo , Interleucina-17/metabolismo , Neutrófilos/metabolismo , Adulto , Biopsia , Bronquios/metabolismo , Bronquios/patología , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/metabolismo , Infiltración Neutrófila , Nariz/patología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Factores de RiesgoRESUMEN
The development of tools to monitor water quality is mandatory in a scenario where clean water resources are decreasing. Here, the biosensing capability of an electroactive river sediment consortium was tested towards three model contaminants (glutaraldehyde, nickel(II) and chromium(III)). The proposed biosensor is a small membrane-less single chamber Microbial Fuel Cell (MFC), fabricated by 3D printing. Its semi-continuous mode of operation resulted in long-term current profile stability and reproducibility. A linear trend of response was obtained for glutaraldehyde in a concentration range of 5-1000â¯ppm. After the recovery of the electroactive consortium activity, the MFC-based biosensors were shown to be sensitive towards Ni(II) and Cr(III), at concentrations above 2â¯mgâ¯L-1. To effectively analyze biosensor response, a novel algorithm was proposed, offering advantages for the realization of energy-saving protocols for MFC-biosensor data transmission. Implementation of the device and method, from laboratory test to real environment, can offer a low cost in situ system for detection of water contaminants.
Asunto(s)
Técnicas Biosensibles , Electricidad , Monitoreo del Ambiente , Agua Dulce , Sedimentos Geológicos/química , Algoritmos , Fuentes de Energía Bioeléctrica , Biopelículas , Cromo/toxicidad , Glutaral/toxicidad , Níquel/toxicidad , TemperaturaRESUMEN
Cryosurgery is one of the techniques available for bronchoscopic treatment of malignant and nonmalignant tracheobronchial stenosis; other techniques are electrosurgery, laser therapy, and endobronchial brachytherapy. Our experience began in 1976 and includes more than 300 patients treated with bronchoscopic cryosurgery either for malignant (the majority) or for nonmalignant tracheobronchial lesions. This study was performed on 234 patients treated in the years 1979 to 1988 subdivided as follows: 183 malignant tumors, 44 benign tumors, and 7 tumors of uncertain prognosis (adeno). The study demonstrated satisfying results in both (palliative in the first case, almost radical in the second one). The aim of our work was to report our personal data and to compare advantages and limits of this technique to others.
Asunto(s)
Enfermedades Bronquiales/cirugía , Broncoscopía , Criocirugía , Estenosis Traqueal/cirugía , Constricción Patológica/cirugía , Criocirugía/métodos , HumanosRESUMEN
After a thorough description of the physiological background, the problem of chest pain is examined with extensive documentation including pictures. It is suggested that meticulous clinical assessment is of even greater value than laboratory tests or instrumental explorations for the accurate diagnosis and appropriate treatment of the condition causing the pain. In other words laboratory and instrumental assessments should be based on and used to confirm an approximate diagnosis formed on clinical data.
Asunto(s)
Dolor/etiología , Tórax/fisiopatología , Abdomen/fisiopatología , Diagnóstico Diferencial , Cardiopatías/diagnóstico , Cardiopatías/fisiopatología , Humanos , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/fisiopatología , Dolor/fisiopatología , Enfermedades de la Columna Vertebral/diagnóstico , Enfermedades de la Columna Vertebral/fisiopatología , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/fisiopatología , Tórax/inervaciónRESUMEN
Six dialysed patients affected by tuberculosis involving the respiratory apparatus were included in the study. Antimycobacterial treatment consisted of polychemiotherapeutic combinations using terizidone (TZ). The need to resort to this drug may be explained by the need to exclude normally used drugs (R/AMP, INH, SM) due to resistance, allergy or organ meiopragia. Five patients received terizidone at a dose of 600-900 mg/day for the entire course of treatment, whereas it was necessary to abandon treatment in one patient due to the onset of depressive symptoms which then rapidly regressed following the suspension of TZ therapy. The good level of tolerance demonstrated in the 5 remaining cases confirm the inclusion of this drug in the treatment of a limited number of cases of tuberculosis in dialysed patients.
Asunto(s)
Antituberculosos/uso terapéutico , Isoxazoles , Oxazoles/uso terapéutico , Oxazolidinonas , Diálisis Renal , Tuberculosis Pulmonar/tratamiento farmacológico , Adulto , Antituberculosos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxazoles/efectos adversosRESUMEN
Eighteen patients hospitalised with acute bronchial asthma are examined. Nine were given aerosol treatment with an ipratropium bromide solution and 45 minutes later with a phenoterol solution. The remaining 9 were given the same treatment in reverse order. The results obtained showed that phenoterol has a stronger bronchodilatory activity than ipratropium bromide, especially when administered after the anticholinergic product.
Asunto(s)
Asma/tratamiento farmacológico , Derivados de Atropina/administración & dosificación , Broncodilatadores/administración & dosificación , Fenoterol/administración & dosificación , Ipratropio/administración & dosificación , Enfermedad Aguda , Adulto , Aerosoles , Anciano , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Distribución AleatoriaRESUMEN
The use of four cardioselective beta-blockers in a group of patients with chronic obstructive bronchopneumopathies was examined. Of the 4 drugs the only possible one for use in this patient category was atenolol which produced significant bronchial dilation after spray treatment, thus demonstrating the responsiveness of beta 2-receptors to pharmacological stimulus.
Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Acebutolol/administración & dosificación , Acebutolol/farmacología , Acebutolol/uso terapéutico , Aerosoles , Anciano , Atenolol/administración & dosificación , Atenolol/farmacología , Atenolol/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Femenino , Volumen Espiratorio Forzado , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Enfermedades Pulmonares Obstructivas/fisiopatología , Masculino , Metaproterenol/administración & dosificación , Persona de Mediana Edad , Pindolol/administración & dosificación , Pindolol/farmacología , Pindolol/uso terapéutico , Propranolol/administración & dosificación , Propranolol/farmacología , Propranolol/uso terapéuticoAsunto(s)
Antagonistas Adrenérgicos beta/farmacología , Indenos/farmacología , Esfuerzo Físico/efectos de los fármacos , Propanolaminas/farmacología , Prostaglandinas/sangre , 6-Cetoprostaglandina F1 alfa/sangre , Adolescente , Adulto , Dinoprostona , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Prostaglandinas E/sangre , Prostaglandinas E Sintéticas/sangre , Tromboxano B2/sangreAsunto(s)
Neoplasias del Mediastino/patología , Adolescente , Adulto , Biopsia , Femenino , Humanos , Metástasis Linfática , Masculino , Mediastino/patología , Persona de Mediana Edad , PronósticoRESUMEN
BACKGROUND: A number of treatments, including Nd-YAG laser therapy, brachytherapy, cryotherapy, electrocautery, and photodynamic therapy, can re-open the obstructed bronchial lumen in patients with inoperable obstructive bronchial tumours. None of these is considered to be a "gold standard". METHODS: The results of a retrospective study of 98 patients treated by radiofrequency tissue ablation and subsequent cryotherapy between January 1994 and June 1995 are reported. The patients were divided in two groups according to whether they were treated either after (group 1, n = 50) or before (group 2, n = 48) radiotherapy and/or chemotherapy. Bronchoscopic follow up was performed. The intervention was considered successful if the lumen was opened by > 80% and partially successful if it was opened by > 50%. RESULTS: In group 1 treatment was successful in 60%, partially successful in 32%, and unsuccessful in 8%. The median survival time was five months from the time of bronchoscopic surgery. In group 2 treatment was successful in 66%, partially successful in 21.5%, and unsuccessful in 12.5%, with a median survival time of 14 months from the time of bronchoscopic treatment. Forty patients (24 in group 1 and 16 in group 2) received a Dumon stent. CONCLUSIONS: Radiofrequency bronchoscopic surgery with cryotherapy appears to be a useful technique in the treatment of tracheobronchial obstruction.