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1.
Sci Rep ; 13(1): 21068, 2023 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-38030672

RESUMEN

Plankton are key ecological indicators for assessing the impacts of human-induced pressures like climate change and waste-water discharge. Here, 26 years (1988-2015) of biweekly in-situ chlorophyll-a concentration, mesozooplankton biomass and remotely-sensed sea surface temperature (SST) data are utilized to investigate long-term changes of plankton biomass and timing of growth (phenology) in relation to warming, in a coastal region of the Saronikos Gulf (Aegean Sea). A Waste-Water Treatment Plant (WWTP) was established in 1995, leading to decreased nutrient concentrations circa 2004. Overall, the results indicate an interplay between warming and changes in ecological status. During higher nutrient input (1989-2004), a temporal mismatch between zooplankton and phytoplankton, and a positive zooplankton growth-SST association, are evident. Conversely, in the warmer, less mesotrophic period 2005-2015, an earlier timing of zooplankton growth (related to copepod abundance) synchronizes with phytoplankton growth, including a secondary autumn growth period. Concurrently, an abrupt negative interannual relationship between SST and mesozooplankton, and a summer biomass decrease (linked with cladoceran abundance) are observed. This work provides evidence that current warming could alter plankton abundance and phenology in nearshore Eastern Mediterranean ecosystems, suggesting shifts in plankton community composition that could trigger potential cascading effects on higher trophic levels.


Asunto(s)
Ecosistema , Plancton , Animales , Humanos , Cadena Alimentaria , Fitoplancton , Zooplancton , Biomasa
3.
Clin Neurophysiol ; 131(1): 167-176, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31794958

RESUMEN

OBJECTIVE: Essential tremor (ET) prominently affects the upper-limbs during voluntary movements, but can also affect the lower-limbs, head, and chin. Although deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of thalamus improves both clinical ratings and quantitative measures of tremor, no study has quantified effects of DBS on tremor across multiple body parts. Our objective was to quantify therapeutic effects of DBS across multiple body parts in ET. METHODS: We performed quantitative assessment of tremor in ET patients who had DBS for at least one year. We assessed tremor on and off VIM-stimulation using triaxial accelerometers on the upper-limbs, lower-limbs, head and chin during seated and standing tasks. RESULTS: VIM-DBS significantly reduced tremor, but there was no statistical difference in degree of tremor reduction across the measured effectors. Compared to healthy controls, ET patients treated with DBS showed significantly greater tremor power (4-8 Hz) across all effectors during seated and standing tasks. CONCLUSIONS: VIM-DBS reduced tremor in ET patients. There was no significant difference in the degree of tremor reduction across the measured effectors. SIGNIFICANCE: This study provides new quantitative evidence that VIM-DBS is effective at reducing tremor across multiple parts of the body.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Temblor Esencial/terapia , Núcleos Talámicos Ventrales/fisiología , Aceleración , Acelerometría/instrumentación , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Mentón/fisiopatología , Temblor Esencial/fisiopatología , Femenino , Mano/fisiopatología , Cabeza/fisiopatología , Humanos , Pierna/fisiopatología , Masculino , Persona de Mediana Edad , Sedestación , Posición de Pie
4.
Mar Environ Res ; 152: 104791, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31640887

RESUMEN

Harmful invader ctenophore Mnemiopsis leidyi's expansions in the Eurasian Seas, its spatio-temporal population dynamics depending on environmental conditions in recipient habitats have been synthesized. M. leidyi found suitable temperature, salinity and productivity conditions in the temperate and subtropical environments of the semi-enclosed seas, in the coastal areas of open basins and in closed water bodies, where it created autonomous populations. M. leidyi changes its phenology depending on seasonal temperature regime in different environments. We assessed ranges of sea surface temperature, sea surface salinity and sea surface chlorophyll values, sufficient for M. leidyi general occurrence and reproduction based on comprehensive long-term datasets, contributed by co-authors. This assessment revealed that there are at least two eco-types (Southern and Northern) in the recipient seas of Eurasia with features specific for their donor areas. The range of thresholds for M. leidyi establishment, occurrence and life cycle in both eco-types depends on variability of environmental parameters in their native habitats.


Asunto(s)
Ctenóforos , Especies Introducidas , Animales , Océanos y Mares , Dinámica Poblacional , Reproducción , Salinidad
5.
Lupus ; 28(1): 3-10, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30501463

RESUMEN

Systemic lupus erythematosus (SLE) is characterized by aberrant production of auto-antibodies and a sexual dimorphism both in the phenotypic expression and frequency of the disease between males and females. The striking female predominance was initially attributed primarily to sex hormones. However, recent data challenge this simplistic view and point more towards genetic and epigenetic factors accounting for this difference. More specifically, several SLE-associated single-nucleotide polymorphisms (SNPs) have been found to play an important role in the gender predilection in SLE. Their effect is mediated through their involvement in sex-hormone and immune system signalling and dysregulation of the expression of genes and miRNAs pertinent to the immune system. Additionally, the genetic factors are interchangeably associated with epigenetic modifications such as DNA methylation and histone modification, thus revealing a highly complex network of responsible mechanisms. Of importance, disturbance in the epigenetic process of X chromosome inactivation in females as well as in rare X chromosome abnormalities leads to increased expression of X-linked immune-related genes and miRNAs, which might predispose females to SLE. Microbiota dysbiosis has also been implicated in the sexual dimorphism by the production of oestrogens within the gut and the regulation of oestrogen-responsive immune-related genes. Sexual dimorphism in SLE is an area of active research, and elucidation of its molecular basis may facilitate ongoing efforts towards personalized care.


Asunto(s)
Cromosomas Humanos X/genética , Lupus Eritematoso Sistémico/genética , Factores Sexuales , Metilación de ADN , Disbiosis , Epigénesis Genética , Femenino , Hormonas Esteroides Gonadales/fisiología , Humanos , Sistema Inmunológico , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/fisiopatología , Masculino , MicroARNs/genética , Polimorfismo de Nucleótido Simple
6.
Mar Pollut Bull ; 95(1): 28-39, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25892079

RESUMEN

PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also independently performed. The comparison between meta-analysis results and IAs shows similarities for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification of additional research themes targeting research topics that are requested to the achievement of GES.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Ecosistema , Política Ambiental , Océanos y Mares , Monitoreo del Ambiente/métodos , Europa (Continente) , Presión
7.
Phlebology ; 29(1): 4-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23188816

RESUMEN

We present a case of non-involuting congenital haemangioma (NICH) of the right eyelid which was present at birth as a purpuric macule but increased in size to cause significant obstruction of vision. At four years of age the lesion was treated with fluroscopic ultrasound-guided sclerotherapy using 0.5% sodium tetradecyl suphate foam and surgically debulked 16 days later. Histopathology was negative for glucose transporter-1 stain confirming the diagnosis. The residual segments were subsequently treated in three further sessions of sclerotherapy in the ensuing three years. This treatment approach resulted in a good cosmetic and functional outcome with no associated complications. To our knowledge, this is the first published case of a histologically confirmed NICH treated primarily with sclerotherapy.


Asunto(s)
Enfermedades de los Párpados/cirugía , Enfermedades de los Párpados/terapia , Hemangioma/cirugía , Hemangioma/terapia , Neoplasias Vasculares/cirugía , Neoplasias Vasculares/terapia , Niño , Preescolar , Medios de Contraste/química , Endotelio/patología , Enfermedades de los Párpados/congénito , Femenino , Fluoroscopía , Transportador de Glucosa de Tipo 1/metabolismo , Hemangioma/congénito , Humanos , Imagen por Resonancia Magnética , Escleroterapia , Tetradecil Sulfato de Sodio/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía Intervencional , Neoplasias Vasculares/congénito
8.
Adv Mar Biol ; 47: 253-309, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15596169

RESUMEN

We compare the nature of copepod outfluxes of nonliving matter, the factors controlling their rate and their fate, and finally their role, particularly their relative importance in the carbon and nitrogen cycle. Copepods release dissolved matter through excretion and respiration and particulate matter through production of faecal pellets, carcasses, moults, and dead eggs. Excretion liberates several organic C, N, and P compounds and inorganic N and P compounds, with inorganic compounds constituting the larger part. The faecal pellets of copepods are covered by a peritrophic membrane and have a highly variable size and content. There is less information on the nature of other copepod particulate products. The weight-specific rates of posthatch mortality, respiration, excretion, and faecal pellet production have similar C or N levels and are higher than those of moulting and egg mortality. In general, most important factors controlling these rates are temperature, body mass, food concentration, food quality, and faunistic composition. Physical and biological factors govern the vertical fate of copepod products by affecting their sedimentation speed and concentration gradient. The physical factors are sinking speed, advection, stratification, turbulent diffusion, and molecular diffusion. They influence the sedimentation speed and degradation of the copepod products. The biological factors are production, biodegradation (by zooplankton, nekton, and microorganisms) and vertical migration of copepods (diel or seasonal). Physical degradation and biodegradation by zooplankton and nekton are faster than biodegradation by microorganisms. The most important copepod outfluxes are excretion and faecal pellet production. Excretion offers inorganic nutrients that can be directly used by primary producers. Faecal pellets have a more important role in the vertical transport of elements than the other particulate products. Most investigation has focused on carbon burial in the form of copepod faecal pellets, measured by sediment traps, and on the role of ammonia excretion in nutrient recycling. Full evaluation of the role of copepod products in the transport and recycling of elements and compounds requires a quantification of all copepod products and their different fates, particularly detritiphagy, remineralization, and integration as marine snow.


Asunto(s)
Carbono/metabolismo , Copépodos/metabolismo , Ecosistema , Nitrógeno/metabolismo , Animales , Heces/química , Respiración , Agua de Mar
9.
J Gerontol A Biol Sci Med Sci ; 56(12): B524-32, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11723145

RESUMEN

The purpose of this study was to examine the ability of young and elderly individuals to control submaximum levels of force (5-90%) during continuous and rapid discrete isometric contractions of the quadriceps femoris. Participants were 24 young (25.3 +/- 2.8 years) and 24 elderly individuals (73.3 +/- 5.5 years) that were healthy and active. The strength of elderly participants was approximately 40% lower than young participants. The standard deviation and coefficient of variation (CV) of force were greater during discrete contractions than during continuous isometric contractions. During continuous isometric contractions, young and elderly participants exhibited similar CVs of force. During discrete contractions, however, elderly participants exhibited greater CVs for peak force and impulse and greater standard deviations and CVs for temporal characteristics than young participants. Results suggest that the control of force in active elderly people declines only during rapid discrete contractions and that this decline may be associated with declines in temporal characteristics of the force production.


Asunto(s)
Envejecimiento/fisiología , Contracción Isométrica/fisiología , Actividad Motora/fisiología , Músculo Esquelético/fisiología , Adulto , Anciano , Femenino , Humanos , Masculino , Muslo , Factores de Tiempo
10.
J AOAC Int ; 82(4): 883-92, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10444828

RESUMEN

Aflatoxins (AFs) B1, B2, G1, and G2 in locally produced and imported foodstuffs (nuts, cereals, oily seeds, pulses, etc.) were monitored and controlled systematically and effectively from 1992-1996. Samples (peanuts, pistachios, etc.) with total AFs above the Cyprus maximum level (ML) of 10 micrograms/kg fluctuated between 0.7 and 6.9%. The results indicate the effectiveness of monitoring, as well as the need for constant surveillance and control, especially at critical control points (sites of import, primary storage, etc.), to prevent unfit products from entering the Cyprus market. The control included sampling, retainment, analysis, and destruction of foodstuff lots with AF levels above MLs. The highest incidence of aflatoxin contamination was observed in peanut butter (56.7%) and the highest level of AF B1 was found in peanuts (700 micrograms/kg). Levels of AF M1 in raw and pasteurized milk analyzed in 1993, 1995, and 1996 were within both the Cyprus ML (0.5 microgram/L) and the lower ML (0.05 microgram/L) of some European countries. Only 12% of samples had detectable levels of AF M1. Analyses were performed by immunochemical methods. When recoveries were lower than 80%, the AF levels were corrected for recovery.


Asunto(s)
Aflatoxinas/análisis , Análisis de los Alimentos , Contaminación de Alimentos/prevención & control , Aflatoxina B1/análisis , Aflatoxina M1/análisis , Animales , Chipre , Grano Comestible/química , Leche/química , Nueces/química , Control de Calidad , Reproducibilidad de los Resultados , Semillas/química
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