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2.
Sci Total Environ ; 599-600: 560-571, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28494282

RESUMEN

Distribution of microplastics particles (MPs) in the water column is investigated on the base of 95 water samples collected from various depths in the Baltic Sea Proper in 2015-2016. Fibres are the prevalent type of MPs: 7% of the samples contained small films; about 40% had (presumably) paint flakes, while 63% contained coloured fibres in concentrations from 0.07 to 2.6 items per litre. Near-surface and near-bottom layers (defined as one tenth of the local depth) have 3-5 times larger fibre concentrations than intermediate layers. Laboratory tests demonstrated that sinking behaviour of a small and flexible fibre can be complicated, with 4-fold difference in sinking velocity for various random fibres' curvature during its free fall. Numerical tests on transport of fibres in the Baltic Sea Proper were performed using HIROMB reanalysis data (2007) for the horizontal velocity field and laboratory order-of-magnitude estimates for the sinking velocity of fibres. The model takes into account (i) motion of fibres together with currents, (ii) their very slow sinking, and (iii) their low re-suspension threshold. Sensitivity of the final distribution of fibres to variations of those parameters is examined. These experiments are the first step towards modelling of transport of fibres in marine environment and they seem to reproduce the main features of fibres distribution quite well.

3.
Mar Pollut Bull ; 108(1-2): 105-12, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-27184128

RESUMEN

Simplified physical models and geometrical considerations reveal general physical and dynamical properties of microplastic particles (0.5-5mm) of different density, shape and size in marine environment. Windage of extremely light foamed particles, surface area and fouling rate of slightly positively buoyant microplastic spheres, films and fibres and settling velocities of negatively buoyant particles are analysed. For the Baltic Sea dimensions and under the considered idealised external conditions, (i) only one day is required for a foamed polystyrene particle to cross the sea (ca. 250km); (ii) polyethylene fibres should spend about 6-8months in the euphotic zone before sinking due to bio-fouling, whilst spherical particles can be retained on the surface up to 10-15years; (iii) for heavy microplastic particles, the time of settling through the water column in the central Gotland basin (ca. 250m) is less than 18h. Proper physical setting of the problem of microplastics transport and developing of physically-based parameterisations are seen as applications.


Asunto(s)
Monitoreo del Ambiente/métodos , Modelos Teóricos , Plásticos/análisis , Agua de Mar/química , Contaminantes Químicos del Agua/análisis , Tamaño de la Partícula , Plásticos/química , Poliestirenos/análisis , Poliestirenos/química , Politetrafluoroetileno/análisis , Politetrafluoroetileno/química , Propiedades de Superficie , Contaminantes Químicos del Agua/química
4.
Biofizika ; 30(2): 239-43, 1985.
Artículo en Ruso | MEDLINE | ID: mdl-2985124

RESUMEN

It is shown by ESR method that 8-methoxypsoralen (8-MOP) under low temperature UV-irradiation has no influence on free radical formation of saturated fatty acids (FA). Under the same conditions the quantum yield of free radical photogeneration for unsaturated FA (oleate and limolenate) after addition of 8-MOP increased 7.5-15 times. The ESR spectrum of free radicals generated after interaction of 8-MOP with polyunsaturated FA, may be presented as superposition of signals-CH-(CH = CH)2-, -CH2CHCH2- and -CH2CH2. The molecular mechanism of photosensitized reactions is discussed.


Asunto(s)
Metabolismo de los Lípidos , Metoxaleno/farmacología , Rayos Ultravioleta , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres , Técnicas In Vitro , Cinética , Fotoquímica
5.
Urologiia ; (6): 34-7, 2002.
Artículo en Ruso | MEDLINE | ID: mdl-12577576

RESUMEN

Iochimbin hydrochloride was given to 153 men with erectile dysfunction. The results are available for 140 of them. The ability of iochimbin in a single dose of 5-10 mg to enhance arterial blood inflow to cavernous bodies of the penis was confirmed by dynamic angiopenoscintigraphy and Doppler ultrasonography. Iochimbin hydrochloride in a mean daily dose of 15-20 mg proved effective in erectile dysfunction--38 to 84% responders depending on the type of erectile dysfunction. Occasional side effects can be relieved by reducing the drug dose.


Asunto(s)
Antagonistas Adrenérgicos alfa/uso terapéutico , Disfunción Eréctil/tratamiento farmacológico , Yohimbina/uso terapéutico , Administración Oral , Antagonistas Adrenérgicos alfa/administración & dosificación , Antagonistas Adrenérgicos alfa/efectos adversos , Adulto , Anciano , Disfunción Eréctil/diagnóstico por imagen , Disfunción Eréctil/etiología , Disfunción Eréctil/psicología , Humanos , Masculino , Persona de Mediana Edad , Pene/irrigación sanguínea , Pene/diagnóstico por imagen , Cintigrafía , Factores de Riesgo , Ultrasonografía Doppler , Yohimbina/administración & dosificación , Yohimbina/efectos adversos
6.
Acta Naturae ; 6(4): 27-39, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25558392

RESUMEN

Replication-defective adenoviral vectors are effective molecular tools for both gene therapy and gene vaccination. Using such vectors one can deliver and express target genes in different epithelial, liver, hematopoietic and immune system cells of animal and human origin. The success of gene therapy and gene vaccination depends on the production intensity of the target protein encoded by the transgene. In this work, we studied influence of Toll-like receptors (TLR) agonists on transduction and expression efficacy of adenoviral vectors in animal and human antigen-presenting cells. We found that agonists of TLR2, 4, 5, 7, 8 and 9 significantly enhance a production of the target protein in cells transduced with adenoviral vector having the target gene insert. The enhancement was observed in dendritic cells and macrophages expressing cytoplasmic (GFP), membrane (HA) or secretory (SEAP) proteins encoded by the respective rAd-vectors. Experiments in mice showed that enhancement of the transgene expression can be achieved in the organism of animals using a pharmaceutical-grade TLR4-agonist. In contrast to other TLR-agonists, the agonist of TLR3 substantially suppressed the expression of transgene in cells transduced with adenoviral vectors having insert of GFP or SEAP target genes. We propose that the enhancement of transgene expression is linked to the activation of MyD88→ NF-kB, while the inhibition of transgene expression depends on TRIF→ IRF signaling pathways. Both of these pathways jointly exploited by TLR4-agonists lead to the enhancement of transgene expression due to the dominant role of the MyD88→ NF-kB signaling.

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