RESUMO
Four hundred fifty soil samples of the orders of Alfisols, Inceptisols, Endisols, and Vertisols from Karditsa, Trikala, and Larissa (Central Greece) were collected over a three-year period. In these samples we analyzed potentially toxic elements (PTEs) and soil properties known to affect their mobility. High regression coefficients were observed between soil pH and PTE concentrations in Alfisols, reflecting that soil pH is the dominant characteristic influencing PTEs. In Inceptisols, there was a significant interaction among the studied PTEs, probably due to PTEs having the same origin. The Endisol samples had high sand content and electrical conductivity values, resulting in high availability of all studied PTEs. In Vertisols, clay content proved to be the most important parameter influencing PTE levels. Factor analysis was also used in order to clarify the possible sources of metals in the studied areas.
Assuntos
Monitoramento Ambiental , Poluentes do Solo/análise , Solo/química , GréciaRESUMO
Exercise causes changes in the heart in response to the hemodynamic demands of increased systemic and pulmonary requirements during exercise. Understanding these adaptations is of great importance, since they may overlap with those caused by pathological conditions. Initial descriptions of athlete's heart focused mainly on chronic adaptation of the left heart to training. In recent years, the substantial structural and functional adaptations of the right heart have been documented, highlighting the complex interplay with left heart. Moreover, there is evolving evidence of acute and chronic cardiac damage, mainly involving the right heart, which may predispose subjects to atrial and ventricular arrhythmias, configuring an exercise-induced cardiomyopathy. The aim of this article is to review the current knowledge on the physiologic and pathophysiologic changes in the right heart in highly trained athletes.
Assuntos
Cardiomegalia Induzida por Exercícios/fisiologia , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Direita/fisiopatologia , Resistência Física , Esportes , Adaptação Fisiológica , Humanos , Modelos CardiovascularesRESUMO
The purpose of this work was to provide information on As and heavy metals content in surface soils of the Almyros area, in Central Greece. A 3-year (2009-2011) research was conducted, in order to investigate the possible temporal variation of As and heavy metal levels. Each year, a number of 251 soil samples (753 totally number of samples) were collected from the area studied, using a Differential Global Positioning System (D.G.P.S.). Soil samples were analyzed for physicochemical parameters and for pseudo-total content of metals, after digestion with Aqua Regia. Thematic maps were created, with Geographic Information Systems (GIS) techniques, using geostatistical tools. The corresponding topographical diagrams covering 15,000 ha of the study area were digitized. The thematic maps and the geostatistical analysis tools were conducted with the use of ArcGIS and the extensions Geostatistical Analyst, Spatial Analyst, and 3D analyst. Factor analysis was conducted in order to assess the possible sources of the pollution. The levels of As and metals determined were lower than the maximum permitted, except for Cd, which content was, in some cases, higher than the critical limits for soils. No statistical differences were observed among the years of the study, although a trend of continuous increasing of their content was detected. Significant correlations between heavy metal fractions and soil physicochemical parameters were obtained and discussed.
Assuntos
Arsênio/análise , Metais Pesados/análise , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Grécia , Ácido Clorídrico/química , Ácido Nítrico/química , Solo/químicaRESUMO
Cardiotrophin-1 (CT-1), a member of interleukin (IL)-6 family, was originally isolated for its ability to induce a hypertrophic response in neonatal cardiac myocytes. This cytokine mediates a pleiotropic set of growth and differentiation activities through a unique receptor system, consisting of IL-6 receptor (IL-6R) and a common signal transducer, the glycoprotein 130 (gp130). Both in humans and in mice, CT-1 mRNA has been detected in several tissues, such as liver tissue, adipose tissue, and tissues in the respiratory and nervous systems; in each of these tissues it performs different functions. Predominant actions of CT-1 are on the heart, where it is synthesized and where it provides first myocardial protection by promoting cell survival and proliferation, it carries on its haemodynamic effects and endocrine properties, and finally, it predisposes the heart to pathological conditions. The aim of this review is to describe the pathophysiological mechanisms through which CT-1 carries out its activities, especially on the heart, and its potential contribution as a disease marker in clinical cardiology. Recent studies have confirmed its active role in promoting structural changes typical of most common cardiovascular disease, such as hypertension, valve diseases, congestive heart failure, and coronary artery disease. In fact, CT-1 induces myocyte hypertrophy and collagen synthesis, thereby participating in the progression of ventricular remodelling, which results in cardiac muscle failure at the latest stage. CT-1 plasma levels are elevated in patients with hypertension and coronary artery diseases, and they are also correlated with the severity of valve diseases and heart failure. Therefore, CT-1 may represent a diagnostic, staging, and prognostic biomarker of cardiovascular diseases.
Assuntos
Doenças Cardiovasculares/metabolismo , Citocinas/metabolismo , Citocinas/fisiologia , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Citocinas/genética , Humanos , Modelos Biológicos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologiaRESUMO
The main purpose of this investigation was the monitoring of Zn and Cu levels in soils of central Greece over three consecutive years (2005 to 2007). Soil samples were analysed for available forms (after extraction with DTPA) and for total concentrations (after digestion with Aqua Regia) of Zn and Cu. A temporal variability, from 2005 to 2007, was observed, as an increasing of 25.5% in available Zn, 25.1% in total Zn, 209% in available Cu and 19.6% in total Cu concentrations were recorded. A spatial variability was also observed and illustrated by the respective thematic maps created using geographic information systems (GIS). Significant correlations among metals concentrations and soil physicochemical parameters were obtained and discussed.
Assuntos
Cobre/análise , Monitoramento Ambiental , Poluentes do Solo/análise , Solo , Zinco/análise , Sistemas de Informação Geográfica , Grécia , Fatores de TempoRESUMO
Over the last decades, there has been a significant increase in incidence and prevalence of heart failure, a major cause of cardiac morbidity and mortality. Measurements of neurohormones, in particular B-type natriuretic peptide (BNP), can significantly improve diagnostic accuracy, and also correlate with long-term morbidity and mortality in patients with chronic heart failure presenting to the emergency department. BNP is secreted by cardiac ventricles mainly in response to wall stress and neurohormonal factors like the sympathetic nervous system, endothelins, and the rennin-angiotensin-aldosterone system. BNP increases myocardial relaxation and oppose the vasoconstrictive, sodium retaining, and natriuretic effects caused by vasoconstrictive factors. BNP is the first biomarker to prove its clinical value for the diagnosis of left ventricular systolic and diastolic dysfunction but also for the right ventricular dysfunction, guiding prognosis and therapy management. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.
Assuntos
Fator Natriurético Atrial/fisiologia , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/fisiologia , Peptídeo Natriurético Tipo C/fisiologia , Disfunção Ventricular Esquerda/diagnóstico , Biomarcadores/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Humanos , Peptídeo Natriurético Encefálico/uso terapêutico , Prognóstico , Disfunção Ventricular Esquerda/metabolismoRESUMO
Copper and Zn sorption and desorption, among other factors, depend on soil pH, but in soils with different degree of weathering the role of other soil properties (e.g., oxides content and the level of their crystallinity) has not been thoroughly examined. We conducted batch sorption and desorption tests using 21 low-organic C soils that belonged to the soil orders of Entisols, newly developed soils, Inceptisols, and Alfisols, the most weathered soils. Zinc sorption was lower than that of Cu, and its desorption faster, confirming that it is a highly mobile metal. Alfisols had the weaker affinity for metals, due to the lower soil pH typical of this soil order, but also due to the low reactivity colloids they contained. Correlation analyses showed that Fe oxides in Alfisols increased metal release from soils, while they decreased metal desorption from Entisols. We conclude that in low organic matter-content soils, where the protective role of organic colloids is not to be expected, high soil pH alone is not sufficient to protect against metal contamination, but the degree of soil weathering is also important, due to the dominant role of other mineral phases (here, Fe oxides).
Assuntos
Cobre/análise , Substâncias Húmicas/análise , Poluentes do Solo/análise , Solo/química , Tempo (Meteorologia) , Zinco/análise , Adsorção , Coloides , Cobre/química , Monitoramento Ambiental , Compostos Férricos/química , Grécia , Concentração de Íons de Hidrogênio , Região do Mediterrâneo , Poluentes do Solo/química , Zinco/químicaRESUMO
This investigation was performed in order to clarify the degree of heavy metals pollution in forest, agricultural and industrial surface soil samples in relation to pre-anthropogenic soils of Almyros region, in Central Greece. In 2004 and 2005 soil samples were collected and analysed for available (DTPA method) and total (Aqua Regia method) Cd, Cr, Cu, Pb, Zn and Ni concentrations. For each metal the enrichment factor with respect to the levels in pre-anthropogenic soils was calculated. All the types of soils appeared to be less polluted than in other investigations. In agricultural and industrial soils the available Cd concentration was higher than the other metals studied. The enrichment factor of Cu in relation to total concentration has the maximum value of the metals studied.
Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Solo/análise , Agricultura , Indústrias , ÁrvoresRESUMO
The main purpose of this research was to determine the levels of heavy metals in tomato, potato and lettuce, grown in agricultural soils of different soil orders (Alfisols, Endisols and Vertisols), located at Central Greece. Soil samples were analysed for available forms (after extraction with DTPA) and for total concentrations (after digestion with Aqua Regia) of metals. Zn, Cu, Cr and Ni were the common metals detected in the vegetables studied. Pb and Cd concentrations were low and in some cases not detectable. Significant correlations among metals concentrations and soil physicochemical parameters were obtained and discussed. The pH value and the percentage of clay content were found to determine the solubility of metals in the soil and their availability for uptake by plants.