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1.
Clin Exp Immunol ; 179(1): 75-84, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24995908

RESUMEN

Apoptosis of polymorphonuclear neutrophils (PMN) and subsequent 'silent' removal represents an important check-point for the resolution of inflammation. Failure in PMN clearance resulting in secondary necrosis-driven tissue damage has been implicated in conditions of chronic inflammation and autoimmunity. Apoptotic PMN undergo profound biophysical changes that warrant their efficient recognition and uptake by phagocytes before fading to secondary necrosis. In this study, we demonstrate that staurosporine (STS), a non-selective but potent inhibitor of cyclin-dependent kinase and protein kinase C, exerts a drastic impact on PMN apoptosis. PMN treated with STS underwent an unconventional form of cell death characterized by a delayed exposure of aminophospholipids, including phosphatidylserine (PS) and phosphatidylethanolamine and an increased exposure of neo-glycans. STS caused an impaired cellular fragmentation and accelerated DNA fragmentation. Phagocytosis of STS-treated PMN lacking PS on their surfaces was decreased significantly, which highlights the importance of PS for the clearance of apoptotic PMN. Specific opsonization with immune complexes completely restored phagocytosis of STS-treated PMN, demonstrating the efficiency of back-up clearance pathways in the absence of PS exposure.


Asunto(s)
Apoptosis/inmunología , Neutrófilos/inmunología , Complejo Antígeno-Anticuerpo/inmunología , Antígenos de Superficie/metabolismo , Apoptosis/efectos de los fármacos , Células Cultivadas , Fragmentación del ADN/efectos de los fármacos , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Fenotipo , Fosfatidilserinas/farmacología , Estaurosporina/farmacología
2.
Environ Sci Process Impacts ; 16(1): 65-73, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24296745

RESUMEN

Oil spills in the deep-sea environment such as the 2010 Deep Water Horizon oil spill in the Gulf of Mexico release vast quantities of crude oil into the sea-surface environment. Various investigators have discussed the marine transport and fate of the oil into different environmental compartments (air, water, sediment, and biota). The transport of the oil into the atmosphere in these previous investigations has been limited to only evaporation, a volatility dependent pathway. In this work, we studied the aerosolization of oil spill matter via bursting bubbles as they occur during whitecaps in a laboratory aerosolization reactor. By evaluating the alkane content in oil mousse, crude oil, the gas phase, and particulate matter we clearly demonstrate that aerosolization via bursting bubbles is a solubility and volatility independent transport pathway for alkanes. The signature of alkane fractions in the native oil and aerosolized matter matched well especially for the less volatile alkanes (C20-C29). Scanning electron microscope interfaced with energy dispersive X-ray images identified the carbon fractions associated with salt particles of aerosols. Theoretical molecular dynamics simulations in the accompanying paper lend support to the observed propensity for alkanes at air-salt water interfaces of breaking bubbles and the produced droplets. The presence of a dispersant in the aqueous phase increased the oil ejection rate at the surface especially for the C20-C29 alkanes. The information presented here emphasizes the need to further study sea-spray aerosols as a possible transport vector for spilled oil in the sea surface environment.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Modelos Químicos , Petróleo/análisis , Agua de Mar/química , Contaminantes Químicos del Agua/análisis , Contaminantes Atmosféricos/química , Material Particulado/análisis , Contaminación por Petróleo , Contaminantes Químicos del Agua/química
3.
Environ Sci Process Impacts ; 16(1): 53-64, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24296764

RESUMEN

Potential of mean force (PMF) calculations and molecular dynamics (MD) simulations were performed to investigate the properties of oil n-alkanes [i.e., n-pentadecane (C15), n-icosane (C20) and n-triacontane (C30)], as well as several surfactant species [i.e., the standard anionic surfactant sodium dodecyl sulfate (SDS), and three model dispersants similar to the Tween and Span species present in Corexit 9500A] at air/salt water interfaces. This study was motivated by the 2010 Deepwater Horizon (DWH) oil spill, and our simulation results show that, from the thermodynamic point of view, the n-alkanes and the model dispersants have a strong preference to remain at the air/salt water interface, as indicated by the presence of deep free energy minima at these interfaces. The free energy minimum of these n-alkanes becomes deeper as their chain length increases, and as the concentration of surfactant species at the interface increases. The n-alkanes tend to adopt a flat orientation and form aggregates at the bare air/salt water interface. When this interface is coated with surfactants, the n-alkanes tend to adopt more tilted orientations with respect to the vector normal to the interface. These simulation results are consistent with the experimental findings reported in the accompanying paper [Ehrenhauser et al., Environ. Sci.: Processes Impacts 2013, in press, (DOI: 10.1039/c3em00390f)]. The fact that these long-chain n-alkanes show a strong thermodynamic preference to remain at the air/salt water interfaces, especially if these interfaces are coated with surfactants, makes these species very likely to adsorb at the surface of bubbles or droplets and be ejected to the atmosphere by sea surface processes such as whitecaps (breaking waves) and bubble bursting. Finally, the experimental finding that more oil hydrocarbons are ejected when Corexit 9500A is present in the system is consistent with the deeper free energy minima observed for the n-alkanes at the air/salt water interface at increasing concentrations of surfactant species.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación por Petróleo/análisis , Petróleo/análisis , Agua de Mar/química , Tensoactivos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Atmosféricos/química , Atmósfera/química , Modelos Químicos , Simulación de Dinámica Molecular , Contaminantes Químicos del Agua/química
5.
Pediatr Nephrol ; 26(2): 251-6, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21104098

RESUMEN

The production of free radicals can cause renal injury and play an important role in the pathogenesis of idiopathic nephrotic syndrome. Markers of reactive oxygen species (ROS) were evaluated in 48 patients with active nephrotic syndrome (ANS) and 30 age- and gender-matched healthy children. Plasma malondialdehyde (MDA), protein carbonyl, nitrite, copper, zinc, selenium, ascorbic acid, and superoxide dismutase (SOD) levels were estimated in patients with ANS and controls. Measurements were repeated in 39 cases after achievement of remission, and in 10 other children who were in remission of >6 months' duration. Plasma MDA and nitrite levels were significantly higher and selenium was lower in ANS patients compared with controls. Plasma protein carbonyl, copper ascorbic acid, zinc, and superoxide dismutase levels were comparable in ANS patients and controls. Plasma copper level was significantly higher in active cases than in the remission and long-term remission groups. Selenium value showed a rise and then normalized in long-term remission. Among different sub-groups of ANS, no significant differences were found in the levels of various parameters, except plasma selenium, which was significantly lower in first-attack nephrotic syndrome (FANS) in comparison to infrequently relapsing nephrotic syndrome (IRNS) and frequently relapsing nephrotic syndrome (FRNS) patients. Thus, we observed evidence of oxidative stress and impaired antioxidant defense during acute nephrotic syndrome. Antioxidant status recovered completely only during long-term remission.


Asunto(s)
Antioxidantes/metabolismo , Síndrome Nefrótico/sangre , Estrés Oxidativo , Especies Reactivas de Oxígeno/sangre , Análisis de Varianza , Ácido Ascórbico/sangre , Estudios de Casos y Controles , Niño , Preescolar , Cobre/sangre , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Masculino , Malondialdehído/sangre , Nitritos/sangre , Carbonilación Proteica , Recurrencia , Selenio/sangre , Estadísticas no Paramétricas , Superóxido Dismutasa/sangre , Zinc/sangre
6.
Anal Bioanal Chem ; 384(3): 703-12, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16440197

RESUMEN

We report on a new and convenient high-throughput fluorescence technique for determining antioxidant capacities of hydrophilic food samples. The new method is called alphaPROX (anti protein oxidation) and is based on an equimolar complex of diphenylhexatriene propionic acid (DPHPA) and bovine serum albumin (BSA) in aqueous buffer at pH 7.4. DPHPA is a reporter fluorophore that becomes nonfluorescent upon free radical-induced oxidation. In a typical assay, the DPHPA/BSA complex is challenged with peroxyl radicals and shows almost the same susceptibility to oxidation as unlabeled BSA. The progress of protein oxidation and its inhibition by antioxidants at physiological pH is determined from the time-dependent decrease in DPHPA fluorescence intensity. The alphaPROX method was compared to other techniques frequently used to measure antioxidant capacities. In this article, representative results are provided for the inhibitory effects of pure food components, fruit juices, wines, and various polar plant extracts on protein oxidation.


Asunto(s)
Antioxidantes/química , Difenilhexatrieno/análogos & derivados , Análisis de los Alimentos/métodos , Albúmina Sérica Bovina/química , Bebidas/análisis , Difenilhexatrieno/química , Fluorescencia , Frutas/química , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Oxidación-Reducción , Extractos Vegetales/química , Semillas/química , Factores de Tiempo , Vino/análisis
7.
Folia Med (Plovdiv) ; 47(2): 12-7, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16544844

RESUMEN

UNLABELLED: The World Health Organisation defines health as a state of complete physical, mental and social well-being, and not merely the absence of a disease or infirmity. The female breast, surgically considered as a "troubled organ", can be affected by disorders of various types. Its normal morphology can be changed by deformities which may have a serious impact on the mental state of female patients. Assessment of these deformities is essential when doctors should define the inclusion and exclusion criteria for each breast operation that has elements of esthetic surgery in it, the breast being indisputably a symbol of female beauty. When we consider the parameters of normal breast morphology, it is only proper to take into account their dependence on race, national culture, folk psychology, etc. For Bulgarian women, P. Tepavicharova has found that the distance from fossa jugularis to the nipple-areolar complex can have the following characteristic proportions: 15.5-17 cm for a woman 155-160 cm in height and with breast circumference of 75-80 cm; 17-18.5 cm for woman 160-165 cm in height and with breast circumference of 89-95 cm; and 18-20 cm for a woman 165-170 cm in height and with breast circumference of 95-100 cm. J. Lalardie points out that breast stability is determined by three principal factors: skin and its elasticity, the condition of the underlying collagenous structure of the breast, and the firm bond between the skin and fibrous elements. RB Brinks defines the four forms of ptosis of the breast: glandular ptosis, true ptosis, parenchymal maldistribution, and pseudoptosis. According to P. Tepavicharova, the violation of breast symmetry is the major factor triggering a sequence of psychosomatic reactions. CONCLUSIONS: The basic parameters of female breast morphology are the mammary base, mammary perimeter, the forward projection of the breast, symmetry, breast volume, and the state of the axillary extension. The major deviations from normal breast morphology that can have an impact on the quality of life are mammary ptosis, hypertrophy, asymmetry, and deformations of the breast shape as well as the operation cicatrices on the breast. An assessment of the association of the deviations from normal morphology with the correction to normal morphology (with or without dealing with a pathological process) and with the impact on the quality of life is a possible base for objective assessment of the latter parameter.


Asunto(s)
Enfermedades de la Mama/psicología , Enfermedades de la Mama/cirugía , Estética , Calidad de Vida , Femenino , Humanos , Planificación de Atención al Paciente , Satisfacción del Paciente
8.
J Biochem Biophys Methods ; 53(1-3): 193-202, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12406602

RESUMEN

Pumpkin seed oil is rather expensive compared to other vegetable oils. Therefore, it is often adulterated by the addition of cheaper oils. In contrast to other edible oils, the content of Delta 5-sterols is very low, while Delta 7-sterols are dominating. The determination of Delta 5-sterols, especially beta-sitosterol has proven to be a good possibility to detect admixture of cheap vegetable oils to a level below which the economic profit is not significant any more. The presented method is a variant of an analysis concept, which has been published previously in European Food Research and Technology by Mandl et al. [Eur. Food Res. Technol. 209 (1999) 400. ]. It includes saponification of the triglycerides as a first step followed by separation of the potassium salts of the fatty acids from the unsaponifiable fraction by adsorption chromatography. In order to enhance gas chromatographic properties of the analytes, the hydroxyl function of the sterols is derivatized with N-Methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) to the trimethylsilylether. Finally, the analytes are separated on a capillary column of medium polarity (HP 35 MS) in a temperature programmed run within 18 min. Detection of the analytes was done by flame ionization. Special attention was set onto the precision and repeatability of the method.


Asunto(s)
Cromatografía/métodos , Cucurbita/química , Contaminación de Alimentos/análisis , Aceites de Plantas/análisis , Sitoesteroles/análisis , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Aceite de Maíz/análisis , Contaminación de Alimentos/prevención & control , Fraude/prevención & control , Fitosteroles/análisis , Reproducibilidad de los Resultados , Semillas/química , Sensibilidad y Especificidad , Soluciones/análisis , Soluciones/química
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