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1.
Sensors (Basel) ; 23(20)2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37896613

RESUMEN

Patras Gulf pockmark field (Western Greece) is a tectonically controlled field that has been activated at least twice by strong earthquakes (M5.4, 14 July 1993 and M6.4, 8 June 2008), and episodic gas seepages have been recorded in the past using geophysical means. A distributed temperature sensor (DTS) system was deployed inside a shallow pockmark and along an active fault at the northern end of the field. This ongoing experiment represents the first long-term monitoring ever conducted on gas-bearing pockmarks and active faults by the DTS system. For now, we have acquired and analyzed data regarding about 1.56 years. One of the primary objectives of this study is to establish methodological queues for data processing and analysis, including spectral analysis and incomplete data treatment techniques, to be standardized for use in further stages of the experiment. Spectral analysis was proven capable of separating the temperature footprint of background environmental components, such as sea-atmosphere heat flux, tides, and winds/waves, from high-frequency temperature residuals. Those residuals represent unusual events that might be correlated to seismicity. Monitoring the causal relationship between seismic activity and seabed water temperature changes in the field was thus attempted. No significant local earthquakes occurred during the monitoring period. Although the relation between seismicity and irregular seabed water temperature events was not systematic, we postulate that four thermal events have a causative link with the local seismicity. The DTS system constitutes a low-cost monitoring system, and the promising preliminary results of this experiment suggest that it is worth testing for a longer period.

2.
Biomedicines ; 11(2)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36831140

RESUMEN

High-dose intravenous steroid treatment (HDIST) represents the first choice of treatment for multiple sclerosis (MS) relapses. Chronic oral glucocorticoid (GC) administration correlates with bone loss whereas data regarding HDIST in MS are still conflicting. Twenty-five newly diagnosed MS patients (NDMSP) (median age: 37 years) were prospectively studied for the effects of HDIST on bone mineral density (BMD) and bone metabolism. Patients received 1000 mg methylprednisolone intravenously every day for 5 days followed by oral prednisolone tapering over 21 days. Bone metabolism indices were determined prior to GC, on days 2, 4, 6, and 90, and at months 6, 12, 18, and 24 post GC therapy. Femoral, lumbar-spine BMD, and whole-body measurement of adipose/lean tissue were assessed prior to GC-administration and then every six months. Ten patients completed the study. N-terminal-propeptide-procollagen-type-1 and bone-specific alkaline phosphatase showed a significant increase at day-90 (p < 0.05). A transient non-significant fall of BMD was observed at 6 months after GC-administration, which subsequently appeared to be restored. We conclude that HDIST seems not to have long-term negative effects on BMD, while the observed transient increase of bone formation markers probably indicates a high bone turnover phase to GC-administration. Additional prospective studies with larger sample size are needed.

3.
Mar Pollut Bull ; 185(Pt A): 114250, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36274560

RESUMEN

COVID-19 pandemic has led to an increase in certain types of litter, many of which are expected to end up in the marine environment. The present study aimed to monitor the pandemic-related litter pollution along the Greek coastal environment. Overall, 59 beach and 83 underwater clean-ups were conducted. Litter was categorized as: PPE (face masks and gloves), COVID-19-related, single-use plastic (SUP) and takeaway items. PPE, dominated by face masks (86.21 %), accounted for 0.29 % of all litter. The average PPE density was 3.1 × 10-3 items m-2 and 2.59 items/ 100 m. COVID-19-related items represented 1.04 % of the total. Wet wipes showed higher densities (0.67 % of all litter) than in the pre-COVID era, while no increase in SUP and takeaway items was observed. Benthic PPE, dominated by gloves (83.95 %), represented 0.26 % of the total. The mean PPE density was 2.5 × 10-3 items m-2.


Asunto(s)
Playas , COVID-19 , Humanos , Residuos/análisis , Pandemias , Grecia , Monitoreo del Ambiente , Plásticos , Agua
4.
PLoS One ; 17(8): e0273652, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36040980

RESUMEN

Sestrins (Sesns) are a family of highly conserved stress-inducible proteins and various stresses have been shown to strongly up-regulate them. Sestrin 2 (Sesn2) deficiency has been shown to partially suppress pulmonary emphysema. The aim of this study was to evaluate Sesn2 levels in COPD patients and its possible associations with the presence of emphysema and blood eosinophils. All patients underwent lung function testing and high-resolution computed tomography (HRCT) of the chest. The presence of emphysematous lesions in >15% of the pulmonary parenchyma was considered as significant emphysema. Sixty-seven patients were included in the study. 40/67 patients were characterized as having significant emphysema. Patients with significant emphysema had higher levels of Sesn2 (ng/ml) [median (IQR) 6.7 (2.7,10.3 vs 1.09 (0.9,1.9), p<0.001)] and significantly lower % and absolute blood eosinophil counts (cells/µL) compared to patients without emphysema [1 (0, 2) vs 4 (2, 4) p<0.001 and 62 (0, 110) vs 248 (180, 300), p<0.001 respectively]. Sesn2 presented a significant positive correlation to the score of emphysema in HRCT (rs = 0.87, p<0.001) and similar positive but weaker correlation to FRC (rs = 0.27, p = 0.024). Negative correlations were observed between Sesn2 and either the % of blood eosinophils and/or the absolute blood eosinophil count (rs = -0.79, p<0.001, and rs = -0.78, p<0.001 respectively). Sesn2 levels above 1.87 ng/ml showed a high diagnostic performance for the presence of significant emphysema in HRCT with an AUC 0.93, 95% CI (0.85,0.98), p<0.001. Sesn2 could serve as a potential biomarker of emphysema.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Sestrinas/metabolismo , Enfisema/complicaciones , Enfisema/diagnóstico por imagen , Humanos , Proteínas Nucleares/genética , Fenotipo , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfisema Pulmonar/diagnóstico
5.
J Environ Manage ; 308: 114647, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35124306

RESUMEN

Monitoring of marine litter at the sea surface, the beaches and the seafloor is essential to understanding their sources, pathways and sinks and design effective clean-up programs or increase public awareness for reducing litter waste. Up until today, seafloor litter is the least exploited component of marine litter. Although the protocols for recording and assessing seafloor litter in the deep-sea environments are currently being actively defined and practiced, shallow seafloor litter survey protocols are still notably under-developed. Moreover, trawling for fishing, which is the main means for collecting seafloor litter data, needs to be phased out in the coming years due to its high environmental footprint and be replaced by less destructive ways based on underwater imagery. In this paper we propose an integrated approach for assessing in detail the spatiotemporal distribution and composition of seafloor litter in shallow coastal environments, using common towed underwater cameras. Effort has been put to correctly estimating spatial litter densities regarding the true coverage of the visualized area, which was efficiently extracted through photogrammetric reconstruction of the seafloor. Interpretation of the spatial distribution of litter was aided by auxiliary bathymetric and swath sonar backscatter datasets, to determine the seabed geomorphological features that control their dispersion and composition. Local geo-morphology, along with any reported coastal anthropogenic activity, are correlated to seafloor litter densities to investigate the temporal and spatial dynamics that control their distribution and temporal trends in Syros Island, Cyclades, Greece. There, in the context of LIFE DEBAG project, monitoring of an urbanized shallow bay for 3 consecutive years has been performed to assess the impact of an intensive local awareness raising campaign to the local environment. A significant reduction of litter densities under the impact of this campaign has been documented, while links between the seafloor litter transport dynamics and the seabed micro- and macro-topography were made evident. Monitoring litter densities on the seafloor of urbanized shallow bays proved to be a prospective way of tracking marine litter pressures on the local marine environment.


Asunto(s)
Bahías , Plásticos , Monitoreo del Ambiente/métodos , Mar Mediterráneo , Estudios Prospectivos , Residuos/análisis
6.
Mar Pollut Bull ; 174: 113260, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34954635

RESUMEN

The evolution of the bottom water in Amvrakikos Gulf in Ionian Sea at western Greece for a 50-year timespan was assessed by benthic foraminifera assemblages. The degradation of the bottom water of Amvrakikos has been a catalyst for the surface water degradation. The east basin has shown permanent low environmental quality in bottom waters since 1980, while the west basin has been under seasonal hypoxic regime since 2000. The most adverse environmental conditions occurred in 1990-2000 and 2005-2010 coinciding with the recorded fish mortality events. The major cause of the environmental quality improvement of the bottom water is the intrusion of seawater. In western areas of the gulf, where the influence of the seawater is high, the decreased temperature improves the environmental conditions, while in the areas influenced by river discharges (east and northern), the environmental conditions are depended on multiple causes like organic matter input and surface salinity.


Asunto(s)
Foraminíferos , Animales , Monitoreo del Ambiente , Sedimentos Geológicos , Grecia , Agua de Mar
7.
Mar Pollut Bull ; 164: 111974, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33485020

RESUMEN

Aerial and underwater imaging is being widely used for monitoring litter objects found at the sea surface, beaches and seafloor. However, litter monitoring requires a considerable amount of human effort, indicating the need for automatic and cost-effective approaches. Here we present an object detection approach that automatically detects seafloor marine litter in a real-world environment using a Region-based Convolution Neural Network. The neural network is trained on an imagery with 11 manually annotated litter categories and then evaluated on an independent part of the dataset, attaining a mean average precision score of 62%. The presence of other background features in the imagery (e.g., algae, seagrass, scattered boulders) resulted to higher number of predicted litter items compare to the observed ones. The results of the study are encouraging and suggest that deep learning has the potential to become a significant tool for automatically recognizing seafloor litter in surveys, accomplishing continuous and precise litter monitoring.


Asunto(s)
Aprendizaje Profundo , Plásticos , Monitoreo del Ambiente , Humanos , Redes Neurales de la Computación , Residuos/análisis
8.
Mar Pollut Bull ; 150: 110684, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31744610

RESUMEN

The abundance of marine debris was quantified for a total of sixty-two inaccessible beaches in the western Saronikos Gulf, Greece. High resolution images were obtained through vessel-based photography survey, merged into seamless photomosaics, and manually processed to quantify beach litter abundance. A sample of four selected beaches were subjected to detailed photography followed by beach macro-litter (≥ 2.5 cm) in-situ sampling surveys over a period of one year, to calibrate and validate the proposed method. Regression analysis between photographic and in-situ data showed a significant correlation, hence providing a highly accurate regression model to assess the real number of beach litter stranded on the rest of the investigated beaches, exhibiting clear correlations to the hydrodynamic status of the area and, provide an indication of the main litter sources. The proposed method is an easily applicable and useful tool for fast and low-cost macro-litter monitoring in extended, remote coastlines, when only photographic data are available.


Asunto(s)
Playas , Monitoreo del Ambiente , Plásticos , Residuos , Grecia , Fotograbar
9.
Artículo en Inglés | MEDLINE | ID: mdl-29562675

RESUMEN

During the last decades, Mediterranean freshwater ecosystems, especially lakes, have been under severe pressure due to increasing eutrophication and water quality deterioration. In this article, we compared the effectiveness of different data analysis methods by assessing the contribution of environmental parameters to eutrophication processes. For this purpose, principal components analysis (PCA), cluster analysis, and a self-organizing map (SOM) were applied, using water quality data from two transboundary lakes of North Greece. SOM is considered as an advanced and powerful data analysis tool because of its ability to represent complex and nonlinear relationships among multivariate data sets. The results of PCA and cluster analysis agreed with the SOM results, although the latter provided more information because of the visualization abilities regarding the parameters' relationships. Besides nutrients that were found to be a key factor for controlling chlorophyll-a (Chl-a), water temperature was related positively with algal production, while the Secchi disk depth parameter was found to be highly important and negatively related toeutrophic conditions. In general, the SOM results were more specific and allowed direct associations between the water quality variables. Our work showed that SOMs can be used effectively in limnological studies to produce robust and interpretable results, aiding scientists and managers to cope with environmental problems such as eutrophication.


Asunto(s)
Monitoreo del Ambiente/estadística & datos numéricos , Eutrofización , Clorofila A/análisis , Análisis por Conglomerados , Grecia , Lagos , Redes Neurales de la Computación , Análisis de Componente Principal , Calidad del Agua
10.
Mar Pollut Bull ; 129(2): 448-457, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29029981

RESUMEN

We assessed amounts, composition and net accumulation rates every ~15days of beach macro litter (≥2.5cm) on 4 Mediterranean beaches, on Corfu island, N. Ionian Sea, taking into account natural and anthropogenic drivers. Average net accumulation rate on all beaches was found 142±115N/100m/15d. By applying a Generalized Linear Model (GzLM) it was shown that sea transport is the dominant pathway affecting the amount and variability in beach litter loadings. Principal Component Analysis (PCA) on compositional data and indicator items discerned two more pathways of beach litter, i.e. in situ litter from beach goers and wind and/or runoff transport of litter from land. By comparing the PCA results to those from a simple item to source attribution, it is shown that regardless their source litter items arrive at beaches from various pathways. Our data provide baseline knowledge for designing monitoring strategies and for setting management targets.


Asunto(s)
Playas/normas , Monitoreo del Ambiente/métodos , Plásticos/análisis , Residuos/análisis , Islas del Mediterráneo , Mar Mediterráneo , Viento
11.
Artículo en Inglés | MEDLINE | ID: mdl-27483293

RESUMEN

Lake Pamvotis (Greece) is a shallow hypereutrophic lake with a natural tendency to eutrophication. Several restoration measures were applied, but with no long-term success. To examine the causes for this an Artificial Neural Network (ANN) was created in order to simulate the chlorophyll-a (Chl-a) levels and to investigate the role of the associated environmental parameters. The ANN managed to simulate with good correlation the simulated Chl-a and can be considered as a reliable predictor. The relative importance of the environmental parameters to the simulated Chl-a was calculated with the use of the "Partial Derivatives" ("PaD") sensitivity method. The water temperature (WT) and soluble reactive phosphorus (SRP) had the highest relative importance, with values of 50% and 17%, respectively. The synergistic effect of the paired parameters was calculated with the use of the "PaD2" algorithm. The SRP-WT paired parameter was the most influential, with a relative contribution of 22%. The ANN showed that Lake Pamvotis is prone to suffer the effects of climatic change, because of the major contribution of WT. The ANN also revealed that combined nutrients reduction would improve water quality status. The ANN findings can act as an advisory tool regarding any restoration efforts.


Asunto(s)
Monitoreo del Ambiente/métodos , Eutrofización/fisiología , Lagos/análisis , Calidad del Agua/normas , Algoritmos , Clorofila/análogos & derivados , Clorofila A , Monitoreo del Ambiente/instrumentación , Grecia , Lagos/química , Fósforo/análisis
12.
Clin Rheumatol ; 30(1): 57-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21120563

RESUMEN

The aim of this paper is to study the prevalence of Raynaud's phenomenon in young males. Young males were examined prospectively in a district hospital, and laboratory tests were performed on the basis of the clinical history. Young males (3.912), age 18-28 years old, were examined. Raynaud's phenomenon was present in seven men (1,79 per 1.000, 95% CI 0.72-3.68). Three of them had at least one member in their family diagnosed with Raynaud's phenomenon. Three were smokers. All had negative immunological test. Five patients reported having severe attacks and two had only mild ischemic attacks. The treatment was conservative for all patients, two of them necessitated vasodilators. Very low prevalence of Raynaud's phenomenon was observed in this young male group compared with the previous studies.


Asunto(s)
Enfermedad de Raynaud/epidemiología , Adolescente , Adulto , Grecia , Humanos , Isquemia , Masculino , Prevalencia , Reumatología/métodos , Fumar , Vasodilatadores/uso terapéutico
13.
Respir Med ; 103(5): 750-6, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19110408

RESUMEN

BACKGROUND: Collection of exhaled breath condensate (EBC) is a safe, non-invasive method to collect droplets of the airway surface liquid and measure mediators of airway inflammation and oxidative stress, such as cysteinyl-leukotrienes (cys-LTs) and 8-isoprostane. OBJECTIVE: The aim of our study was to investigate baseline values of inflammatory lipid mediators in EBC and their relation to asthma severity. METHODS: Nineteen healthy subjects, 16 mild, 12 moderate and 15 severe asthmatics were studied. All subjects attended a clinic visit for spirometry and EBC collection. The concentrations of exhaled cys-LTs and 8-isoprostane were measured by means of specific enzyme immunoassays. RESULTS: 8-isoprostane levels were significantly increased in mild (49.1+/-5.2 pg/mL, p<0.001), moderate (49.7+/-5.2 pg/mL, p<0.001) and severe asthmatics (77.7+/-7.3 pg/mL, p<0.001), compared to healthy controls (16.4+/-1.6 pg/mL). Moreover, 8-isoprostane levels were significantly higher in severe compared to mild and moderate asthmatics (p<0.01). Cys-LT levels were significantly higher in moderate (34.6+/-4.4 pg/mL, p<0.05) and severe asthmatics (47.9+/-6.0 pg/mL, p<0.001), while no significant difference was found between healthy controls and mild asthmatics. 8-isoprostane levels in EBC of asthmatics strongly correlated with cys-LT levels (r=0.61, p<0.0001). CONCLUSIONS: 8-isoprostane and cys-LT are detectable in EBC of healthy subjects and their levels progressively increase in asthmatic patients according to disease severity. The correlation found between these two lipid mediators indicating a link between oxidative stress and airway inflammation.


Asunto(s)
Asma/fisiopatología , Cisteína/análisis , Dinoprost/análogos & derivados , Leucotrienos/análisis , Adulto , Asma/metabolismo , Pruebas Respiratorias/métodos , Estudios de Casos y Controles , Estudios Transversales , Dinoprost/análisis , Femenino , Volumen Espiratorio Forzado , Grecia , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estrés Oxidativo , Espirometría
14.
J Biomed Opt ; 12(3): 034005, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17614713

RESUMEN

We examine the application of an improved noncontact and noninvasive Raman spectroscopic technique in measuring medicines at therapeutic concentrations in a model system mimicking the anterior chamber of the eye. A 90-deg laser Raman scattering geometry is employed to reduce the direct exposure of the basic cordial ocular tissues to the laser beam and increase the signal-to-noise ratio of the spectra. The technique is applied to a commercially available artificial anterior chamber (AAC) fitted with corneas of porcine eyes. Specific Raman signatures of ciprofloxacin (Ciproxin, a fluoroquinolone based antibiotic, have been resolved. Last, a partial least-squares (PLS) chemometric algorithm has been developed to predict the concentration of ciprofloxacin in AAC over the range from 0 to 1 mgmL with a correlation coefficient R(2)=98.4% and an RMS error of prediction equal to 41 microgmL.


Asunto(s)
Ciprofloxacina/análisis , Córnea/metabolismo , Espectrometría Raman/instrumentación , Espectrometría Raman/métodos , Animales , Diseño de Equipo , Análisis de Falla de Equipo , Técnicas In Vitro , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Porcinos
15.
Lasers Surg Med ; 38(7): 695-703, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16736502

RESUMEN

BACKGROUND AND OBJECTIVES: Laser Raman spectroscopy is an inelastic light scattering technique able to characterize molecules in aqueous environments. The purpose of this work is to develop a non-contact and non-invasive spectroscopic method to identify and eventually quantify the presence of medicines (e.g., antibiotics) and physiological substances (e.g., glucose) in the aqueous humor of the eye. STUDY DESIGN/MATERIALS AND METHODS: A new laser light delivery probe has been developed and adapted to a Raman spectroscopic system with the ability of favorable collection of the Raman light at 90 degrees scattering geometry while scanning the anterior chamber of the eye. Different amounts of ceftazidime, amphotericin B, and glucose had been injected in the aqueous humor of porcine eyes, maximum 24 hours after death and extraction, in-vitro. Raman measurements were excited with a visible (514.5 nm) laser beam at a power of 25 mW and an exposure/acquisition time of 1 second. RESULTS: The specific collection optics and Raman analysis components used in the present work have resolved the Raman signatures of probed molecules and low concentrations of ceftazidime (0.9 mg/mL), amphotericin B (9 microg/mL), and glucose (2 mg/ml) separately injected in the anterior chamber of porcine eyes were detected in vitro. CONCLUSION: This special illumination design gives the opportunity of avoiding the direct exposure to the laser light of basic cordial tissues of the eye, like lens and retina, although an optimum collection of scattered light is accomplished. Concentrations close to the minimum inhibitory concentration (MIC) have been detected for ceftazidime and amphotericin b; the detection of glucose has been realized at concentrations close to the early pathological levels of patients with diabetes.


Asunto(s)
Antibacterianos/análisis , Humor Acuoso/química , Espectrometría Raman , Anfotericina B/análisis , Animales , Ceftazidima/análisis , Glucosa/análisis , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Rayos Láser , Dispersión de Radiación , Espectrometría Raman/instrumentación , Espectrometría Raman/métodos , Porcinos
16.
J Sports Sci ; 23(8): 825-34, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16195034

RESUMEN

In this study, we assessed the effects of a 4 week basic military physical training programme for male recruits of the Hellenic Air Force on the number and distribution of circulating immune cells and adrenergic and adrenocortical hormonal responses. One group of recruits (exercised, n = 48) participated in moderate intermittent physical exercise, whereas a second group (non-exercised controls, n = 9) performed only light work in the barracks. Both groups participated in the same non-physical, classroom-type training and testing. Military training by the exercised group resulted in significant increases in CD4+ T-lymphocytes, renal cortisol excretion and the urinary noradrenaline/adrenaline ratio, together with reductions in neutrophils and the neutrophil/lymphocyte ratio. In the exercised group, the urinary noradrenaline/adrenaline ratio correlated positively with the training-induced changes in CD4+ T-lymphocytes and negatively with changes in the neutrophil/lymphocyte ratio. No significant relationship was found between training-induced increases in cortisol excretion and any of the peripheral blood cell alterations. Our results indicate that 4 weeks of military training consisting of intermittent moderate exercise resulted in a significant increase in CD4+ T-lymphocytes and reduction in neutrophils. These changes were probably driven by alterations in hormonal status, including the significant impact of sympathetic nervous system activation.


Asunto(s)
Catecolaminas/orina , Ejercicio Físico/fisiología , Hidrocortisona/orina , Leucocitos/metabolismo , Personal Militar/educación , Educación y Entrenamiento Físico/métodos , Glándulas Suprarrenales/metabolismo , Humanos , Sistema Inmunológico/metabolismo , Masculino , Valores de Referencia , Estrés Fisiológico/inmunología , Estrés Fisiológico/metabolismo
17.
Am J Psychiatry ; 161(5): 818-25, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15121646

RESUMEN

OBJECTIVE: Ziprasidone is an atypical antipsychotic drug that shows a higher affinity for serotonin 5-HT(2) receptors compared with dopamine D(2) receptors in vitro. The affinity of ziprasidone for these receptors in vivo in patients was examined in a positron emission tomography (PET) study. METHOD: The authors conducted a PET study to evaluate D(2) occupancy (using [(11)C]raclopride) and 5-HT(2) occupancy (using [(18)F]setoperone) in brain regions of interest in 16 patients with schizophrenia or schizoaffective disorder randomly assigned to receive 40, 80, 120, or 160 mg/day of ziprasidone, which reflected the recommended dose range. PET scanning was done after 3 weeks of administration and at trough plasma levels, i.e., 12-16 hours after the last dose. RESULTS: The mean 5-HT(2) receptor occupancy was significantly higher than the mean D(2) receptor occupancy (mean=76%, SD=15%, and mean=56%, SD=18%, respectively). The estimated plasma ziprasidone concentration associated with 50% maximal 5-HT(2) receptor occupancy was almost four times lower than that for D(2) receptor occupancy. CONCLUSIONS: These data affirm that ziprasidone is similar to other novel antipsychotics in having greater 5-HT(2) than D(2) receptor occupancy at therapeutic doses and suggest that the optimal effective dose of ziprasidone is closer to 120 mg/day than to the lower doses suggested by previous PET studies. The relatively high D(2) receptor occupancy, even at trough plasma levels, suggests that ziprasidone is more similar to risperidone and olanzapine in receptor occupancy profile than to clozapine and quetiapine. Since ziprasidone plasma levels show significant (more than twofold) variation within a single dose cycle, studies that are aimed at peak plasma levels (6 hours after the last dose) and that examine extrastriatal regions are required to fully characterize the in vivo occupancy profile of ziprasidone.


Asunto(s)
Antipsicóticos/uso terapéutico , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Piperazinas/uso terapéutico , Receptores de Dopamina D2/metabolismo , Receptores de Serotonina 5-HT2/metabolismo , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/metabolismo , Tiazoles/uso terapéutico , Tomografía Computarizada de Emisión , Adulto , Antipsicóticos/sangre , Antipsicóticos/farmacocinética , Encéfalo/efectos de los fármacos , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Esquema de Medicación , Femenino , Humanos , Masculino , Piperazinas/farmacocinética , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/metabolismo , Pirimidinonas , Racloprida , Receptores de Dopamina D2/efectos de los fármacos , Receptores de Serotonina 5-HT2/efectos de los fármacos , Esquizofrenia/diagnóstico por imagen , Tiazoles/farmacocinética
18.
Chest ; 125(3): 1005-11, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15006961

RESUMEN

STUDY OBJECTIVE: 8-Isoprostane is considered an index of oxidative stress. Measurement of 8-isoprostane in the expired breath condensate, a totally noninvasive method, has not been used to explore the level of inflammation in pulmonary sarcoidosis. Therefore, the aim of our study was to measure the levels of 8-isoprostane in the expired breath condensate of patients with sarcoidosis, and to investigate the relation of 8-isoprostane level to disease activity. PATIENTS: We investigated 30 patients with pulmonary sarcoidosis (active disease, n = 14; nonactive disease, n = 16) and 12 healthy subjects as control group. METHODS: 8-Isoprostane was measured in the expired breath condensate of all subjects, and its levels were compared between the control and sarcoidosis groups as well as between the subgroups of patients with active and nonactive disease. In the group with sarcoidosis, 8-isoprostane levels were further correlated with markers that may reflect disease activity, such as serum angiotensin-converting enzyme (sACE) level, serum calcium level, and pulmonary function test results. RESULTS: The concentration of 8-isoprostane was increased in patients with sarcoidosis compared to control subjects (mean, 64.23 pg/mL; 95% confidence interval [CI], 37.00 to 91.46 pg/mL; vs mean, 20.75 pg/mL; 95% CI, 16.06 to 25.44 pg/mL; p = 0.04). The difference was primarily due to the patients with active disease, who had significantly higher levels of 8-isoprostane (mean, 111.4 pg/mL; 95% CI, 62.56 to 160.30 pg/mL; p < 0.001) compared to patients with nonactive disease (mean, 22.94 pg/mL; 95% CI, 15.89 to 29.99 pg/mL) or healthy subjects. 8-Isoprostane levels in patients with nonactive disease did not differ from those in healthy subjects (p > 0.05). In the patients with sarcoidosis, 8-isoprostane levels were positively correlated with sACE level (p < 0.0001, r = 0.69), but was not correlated with serum calcium level or pulmonary function test values. CONCLUSIONS: Our data suggest that 8-isoprostane levels are increased in the expired breath condensate of patients with sarcoidosis and might serve as an index of disease activity.


Asunto(s)
Pruebas Respiratorias , Dinoprost/análogos & derivados , F2-Isoprostanos/metabolismo , Estrés Oxidativo , Sarcoidosis Pulmonar/metabolismo , Adulto , Biomarcadores/análisis , Calcio/sangre , Estudios Transversales , Femenino , Volumen Espiratorio Forzado , Humanos , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Peptidil-Dipeptidasa A/sangre , Capacidad de Difusión Pulmonar , Sarcoidosis Pulmonar/fisiopatología , Capacidad Vital
19.
Am J Trop Med Hyg ; 68(2): 253-7, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12641421

RESUMEN

We report the case of a 65-year-old woman who presented with severe neurologic complications after envenomation by a viper snake. A computed tomography (CE) scan revealed multiple brain hemorrhagic infarcts. Conservative treatment in this case proved to be sufficient and repetitive CT scans displayed a complete resolution of the radiologic findings. Possible mechanisms for the cerebral infarctions are discussed. The mechanism of infarctions in this case was believed to be the vasomotor and coagulation disorders caused by the toxins present in the snake's venom and was one of the reasons that led to conservative treatment.


Asunto(s)
Infarto Cerebral/diagnóstico , Infarto Cerebral/etiología , Mordeduras de Serpientes/complicaciones , Viperidae , Anciano , Animales , Infarto Cerebral/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Pie , Humanos , Tomografía Computarizada por Rayos X
20.
Pharmacol Biochem Behav ; 74(2): 425-32, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12479964

RESUMEN

The effect of catecholamine depletion, achieved by per-oral administration of 5250 mg alpha-methyl-para-tyrosine (AMPT) given in the 29 h prior to [11C]raclopride positron emission tomography (PET) was studied on measures of dopamine (DA) release, mood, and attention. Neostriatal DA levels in vivo were estimated by comparing the neostriatal DA D(2) receptor binding potential (D(2)RBP) before and after catecholamine depletion using PET and the radiotracer [11C]raclopride. Six healthy subjects completed the protocol. The AMPT treatment increased D(2)RBP significantly by 13.3+/-5.9% (average+/-standard deviation) and decreased plasma levels of the DA metabolite homovanillic acid (HVA) by 62+/-17%, and levels of the norepinephrine (NE) metabolite 3-methoxy-4-hydroxyphenethyleneglycol (MHPG) by 66+/-5%. Catecholamine depletion resulted in decreased happiness, euphoria, energy, talkativeness, vigor, and attentiveness, and in increased sleepiness, fatigue, sedation, and eye blink rate (EBR). These changes were not correlated with the D(2)RBP increments. The results of this study are overall consistent with previous findings by our group using the same methodology in a different cohort of six healthy subjects.


Asunto(s)
Afecto/fisiología , Atención/fisiología , Catecolaminas/fisiología , Receptores de Dopamina D2/metabolismo , Adulto , Antagonistas de Dopamina , Inhibidores Enzimáticos/farmacología , Femenino , Ácido Homovanílico/sangre , Humanos , Masculino , Metoxihidroxifenilglicol/sangre , Pruebas Psicológicas , Desempeño Psicomotor/fisiología , Racloprida , Radiofármacos , Tomografía Computarizada de Emisión , alfa-Metiltirosina/farmacología
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