RESUMEN
Tropical stream ecosystems are under increasing human pressure, making the development of effective restoration approaches and expanding knowledge in this field urgent. This study evaluated the impact of riparian vegetation restoration and environmental context on stream ecosystem functioning by measuring key ecosystem functions - gross primary production (GPP), ecosystem respiration (ER), and nutrient uptake of ammonium and soluble reactive phosphorus - across ten tropical streams in southeastern Brazil. The streams represented a gradient from clearcut areas (impacted reaches) to relatively pristine conditions (reference reaches), including intermediate stages of vegetation recovery (restored reaches). In the short-term (~15-20 years after restoration), restoration led to reduced GPP akin to reference reaches. Yet, ER did not show the anticipated increase, suggesting a longer timeframe is necessary for restored streams to emulate the functional characteristics of reference reaches. Additionally, the restored reaches did not achieve the nutrient uptake efficiencies observed in both impacted and reference reaches, pointing to a partial recovery of ecosystem function. This study suggests that while riparian vegetation restoration contributes positively to certain aspects of stream function, environmental variables less related to this type of restoration, such as discharge and hydromorphology, significantly influence stream ecosystem functioning, highlighting the importance of considering environmental context in restoration efforts. A more holistic approach, possibly encompassing broader hydromorphological and habitat enhancements, is needed to fully restore ecological processes in these vital ecosystems. These insights are critical for informing future tropical stream restoration projects, advocating the use of ecosystem function metrics as comprehensive indicators of ecological recovery and restoration success.
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Ecosistema , Monitoreo del Ambiente , Restauración y Remediación Ambiental , Ríos , Brasil , Restauración y Remediación Ambiental/métodos , Fósforo/análisis , Clima Tropical , Conservación de los Recursos Naturales/métodosRESUMEN
Ciprofloxacin (CIP) is an antimicrobial "pseudo-persistent" in aquatic ecosystems. Once dispersed in the water compartments, it can also affect the microalgae. Thus, the evaluation of its long-term ecotoxicological effects is necessary. CIP interactions with other pharmaceuticals are not well known. In this study, we investigated the toxic effects of CIP alone and combined with caffeine (CAF), using the modified Gompertz model parameters and the chlorophyll-a production of the microalga Raphidocelis subcapitata as endpoints, throughout a 16-day exposure assay. The exposure to CIP alone led to significant reductions of the growth rate and the cell density of the microalgae compared to control groups. The combination with CAF lowered the adverse effects of CIP to R. subcapitata. However, as the toxicity is dynamic, our results indicated that the toxic effects in respect to the studied endpoints changed throughout the exposure period, reinforcing the need for longer-term ecotoxicity assessments.
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The potential impacts of citizen science initiatives are increasing across the globe, albeit in an imbalanced manner. In general, there is a strong element of trial and error in most projects, and the comparison of best practices and project structure between different initiatives remains difficult. In Brazil, the participation of volunteers in environmental research is limited. Identifying the factors related to citizen science projects' success and longevity within a global perspective can contribute for consolidating such practices in the country. In this study, we explore past and present projects, including a case study in Brazil, to identify the spatial and temporal trends of citizen science programs as well as their best practices and challenges. We performed a bibliographic search using Google Scholar and considered results from 2005-2014. Although these results are subjective due to the Google Scholar's algorithm and ranking criteria, we highlighted factors to compare projects across geographical and disciplinary areas and identified key matches between project proponents and participants, project goals and local priorities, participant profiles and engagement, scientific methods and funding. This approach is a useful starting point for future citizen science projects, allowing for a systematic analysis of potential inconsistencies and shortcomings in this emerging field.
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Participación de la Comunidad/métodos , Proyectos de Investigación , Voluntarios , Brasil , Humanos , CienciaRESUMEN
ABSTRACT The potential impacts of citizen science initiatives are increasing across the globe, albeit in an imbalanced manner. In general, there is a strong element of trial and error in most projects, and the comparison of best practices and project structure between different initiatives remains difficult. In Brazil, the participation of volunteers in environmental research is limited. Identifying the factors related to citizen science projects' success and longevity within a global perspective can contribute for consolidating such practices in the country. In this study, we explore past and present projects, including a case study in Brazil, to identify the spatial and temporal trends of citizen science programs as well as their best practices and challenges. We performed a bibliographic search using Google Scholar and considered results from 2005-2014. Although these results are subjective due to the Google Scholar's algorithm and ranking criteria, we highlighted factors to compare projects across geographical and disciplinary areas and identified key matches between project proponents and participants, project goals and local priorities, participant profiles and engagement, scientific methods and funding. This approach is a useful starting point for future citizen science projects, allowing for a systematic analysis of potential inconsistencies and shortcomings in this emerging field.
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Humanos , Proyectos de Investigación , Voluntarios , Participación de la Comunidad/métodos , Ciencia , BrasilRESUMEN
Growing evidence suggests the beneficial effect of aspirin against some types of cancer, particularly of the gastrointestinal tract, and it has been provided for an effect both in cancer prevention as well as in survival improvement of cancer patients. Aspirin benefits increase with duration of treatment, especially after 10years of treatment. The inhibition of platelet activation at sites of gastrointestinal mucosal lesions could be the primary mechanism of action of low-dose aspirin. Indeed, the formation of tumor cell-induced platelet aggregates may favor immune evasion, by releasing angiogenic and growth factors, and also by promoting cancer cell dissemination. Moreover, platelets may contribute to aberrant COX-2 expression in colon carcinoma cells, thereby contributing to downregulation of oncosuppressor genes and upregulation of oncogenes, such as cyclin B1. Platelet adhesion to cancer cells leads also to an increased expression of genes involved in the EMT, such as the EMT-inducing transcription factors ZEB1 and TWIST1 and the mesenchymal marker vimentin. The aspirin-mediated inactivation of platelets may restore antitumor reactivity by blocking the release of paracrine lipid and protein mediators that induce COX-2 expression in adjacent nucleated cells at sites of mucosal injury. Thus, recent findings suggest interesting perspectives on "old" aspirin and NSAID treatment and/or "new" specific drugs to target the "evil" interactions between platelets and cancer for chemoprevention.
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Aspirina/uso terapéutico , Ciclooxigenasa 2/genética , Neoplasias/prevención & control , Activación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Plaquetas/efectos de los fármacos , Quimioprevención , Humanos , Neoplasias/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Transcripción/genéticaRESUMEN
OBJECTIVE: Prolonged maternal separation (PMS) in the first 2 wk of life has been associated with poor growth with lasting effects in brain structure and function. This study aimed to investigate whether PMS-induced undernutrition could cause systemic inflammation and changes in nutrition-related hormonal levels, affecting hippocampal structure and neurotransmission in C57BL/6J suckling mice. METHODS: This study assessed mouse growth parameters coupled with insulin-like growth factor-1 (IGF-1) serum levels. In addition, leptin, adiponectin, and corticosterone serum levels were measured following PMS. Hippocampal stereology and the amino acid levels were also assessed. Furthermore, we measured myelin basic protein and synapthophysin (SYN) expression in the overall brain tissue and hippocampal SYN immunolabeling. For behavioral tests, we analyzed the ontogeny of selected neonatal reflexes. PMS was induced by separating half the pups in each litter from their lactating dams for defined periods each day (4 h on day 1, 8 h on day 2, and 12 h thereafter). A total of 67 suckling pups were used in this study. RESULTS: PMS induced significant slowdown in weight gain and growth impairment. Significant reductions in serum leptin and IGF-1 levels were found following PMS. Total CA3 area and volume were reduced, specifically affecting the pyramidal layer in PMS mice. CA1 pyramidal layer area was also reduced. Overall hippocampal SYN immunolabeling was lower, especially in CA3 field and dentate gyrus. Furthermore, PMS reduced hippocampal aspartate, glutamate, and gamma-aminobutyric acid levels, as compared with unseparated controls. CONCLUSION: These findings suggest that PMS causes significant growth deficits and alterations in hippocampal morphology and neurotransmission.
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Hipocampo/crecimiento & desarrollo , Inflamación/etiología , Desnutrición/etiología , Privación Materna , Aminoácidos/sangre , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Hipocampo/fisiopatología , Inflamación/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Desnutrición/sangre , Ratones , Ratones Endogámicos C57BLRESUMEN
This review article is intended to describe how oxidative stress regulates cardiovascular disease development and progression. Epigenetic mechanisms related to oxidative stress, as well as more reliable biomarkers of oxidative stress, are emerging over the last years as potentially useful tools to design therapeutic approaches aimed at modulating enhanced oxidative stress "in vivo", thereby mitigating the consequent atherosclerotic burden. As a paradigm, we describe the case of obesity, in which the intertwining among oxidative stress, due to caloric overload, chronic low-grade inflammation induced by adipose tissue dysfunction, and platelet activation represents a vicious cycle favoring the progression of atherothrombosis. Oxidative stress is a major player in the pathobiology of cardiovascular disease (CVD). Reactive oxygen species (ROS)- dependent signaling pathways prompt transcriptional and epigenetic dysregulation, inducing chronic low-grade inflammation, platelet activation and endothelial dysfunction. In addition, several oxidative biomarkers have been proposed with the potential to improve current understanding of the mechanisms underlying CVD. These include ROS-generating and/or quenching molecules, and ROS-modified compounds, such as F2-isoprostanes. There is also increasing evidence that noncoding micro- RNA (mi-RNA) are critically involved in post- transcriptional regulation of cell functions, including ROS generation, inflammation, regulation of cell proliferation, adipocyte differentiation, angiogenesis and apoptosis. These molecules have promising translational potential as both markers of disease and site of targeted interventions. Finally, oxidative stress is a critical target of several cardioprotective drugs and nutraceuticals, including antidiabetic agents, statins, renin-angiotensin system blockers, polyphenols and other antioxidants. Further understanding of ROS-generating mechanisms, their biological role as well as potential therapeutic implications would translate into consistent benefits for effective CV prevention.
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Biomarcadores/metabolismo , Enfermedades Cardiovasculares/tratamiento farmacológico , Obesidad/tratamiento farmacológico , Epigenómica , Inflamación , Estrés Oxidativo , Activación Plaquetaria , Especies Reactivas de OxígenoRESUMEN
Visceral obesity is characterized by increased risk of cardiovascular disease as well as higher incidence of malignancies, including colorectal cancer (CRC), although the mechanisms linking excess adiposity with cancer are only partly characterized. Visceral obesity is currently acknowledged as a chronic inflammatory disorder and a growing body of evidence demonstrates the interconnections between obesity-related secretion pattern of adipo/cytokines and CRC. Specific molecules derived from the visceral adipose tissue (VAT), including adiponectin, leptin and resistin, are able to establish a positive feedback loop, thus increasing the proinflammatory and insulin resistant state and promoting tumorigenesis. Interestingly, these molecules have emerged as novel prognostic factors and therapeutic targets. This review will focus on current molecular and clinical evidence linking VAT-related inflammation to CRC initiation and progression, and summarize the role of dietary factors and lifestyle interventions aimed at promoting weight control and physical activity on CRC prevention and prognosis.
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Neoplasias Colorrectales/etiología , Inflamación/etiología , Obesidad/complicaciones , Adipoquinas/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Citocinas/metabolismo , Humanos , Inflamación/metabolismo , Resistencia a la Insulina , Grasa Intraabdominal/metabolismo , Enfermedades Vasculares/etiología , Enfermedades Vasculares/metabolismoRESUMEN
BACKGROUND: Interindividual variability in response to aspirin has been popularized as 'resistance'. We hypothesized that faster recovery of platelet cyclooxygenase-1 activity may explain incomplete thromboxane (TX) inhibition during the 24-h dosing interval. OBJECTIVE: To characterize the kinetics and determinants of platelet cyclooxygenase-1 recovery in aspirin-treated diabetic and non-diabetic patients. PATIENTS/METHODS: One hundred type 2 diabetic and 73 non-diabetic patients on chronic aspirin 100 mg daily were studied. Serum TXB(2) was measured every 3 h, between 12 and 24 h after a witnessed aspirin intake, to characterize the kinetics of platelet cyclooxygenase-1 recovery. Patients with the fastest TXB(2) recovery were randomized to aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily, for 28 days and TXB(2) recovery was reassessed. RESULTS AND CONCLUSIONS: Platelet TXB(2) production was profoundly suppressed at 12 h in both groups. Serum TXB(2) recovered linearly, with a large interindividual variability in slope. Diabetic patients in the third tertile of recovery slopes (≥ 0.10 ng mL(-1) h(-1) ) showed significantly higher mean platelet volume and body mass index, and younger age. Higher body weight was the only independent predictor of a faster recovery in non-diabetics. Aspirin 100 mg twice daily completely reversed the abnormal TXB(2) recovery in both groups. Interindividual variability in the recovery of platelet cyclooxygenase activity during the dosing interval may limit the duration of the antiplatelet effect of low-dose aspirin in patients with and without diabetes. Inadequate thromboxane inhibition can be easily measured and corrected by a twice daily regimen.
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Aspirina/administración & dosificación , Plaquetas/enzimología , Ciclooxigenasa 1/sangre , Diabetes Mellitus Tipo 2/enzimología , Anciano , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Tromboxano B2/sangreRESUMEN
Obesity is associated with increased cardiovascular disease. Metabolic syndrome (MS) identifies substantial additional cardiovascular risk beyond the individual risk factors, and is a powerful predictor of cardiovascular events even regardless of body mass index, thus suggesting a common downstream pathway conferring increased cardiovascular risk. Platelet hyper-reactivity/activation plays a central role to accelerate atherothrombosis and is the result of the interaction among the features clustering in obesity and MS: insulin resistance, inflammation, oxidative stress, endothelial dysfunction. Interestingly, the same pathogenic events largely account for the less-than-expected response to antiplatelet agents, namely low-dose aspirin. The proposed explanations for this phenomenon, besides underdosing of drug and/or reduced bioavailability, subsequent to excess of adipose tissue, include enhanced platelet turnover, leading to unacetylated COX-1 and COX-2 in newly formed platelets as a source of aspirin-escaping thromboxane formation; extraplatelet sources of thromboxane, driven by inflammatory triggers; and enhanced lipid peroxidation, activating platelets with a mechanism bypassing COX-1 acetylation or limiting COX-isozyme acetylation by aspirin. This review will address the complex interactions between platelets and the pathogenic events occurring in obesity and MS, trying to translate this body of mechanistic information into a clinically relevant read-out, in order to establish novel strategies in the prevention/treatment of atherothrombosis.
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Plaquetas/enzimología , Isoenzimas/antagonistas & inhibidores , Síndrome Metabólico/sangre , Obesidad/sangre , Activación Plaquetaria/fisiología , Aspirina/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Humanos , Síndrome Metabólico/complicaciones , Obesidad/complicaciones , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Factores de Riesgo , Trombosis/tratamiento farmacológico , Trombosis/prevención & controlRESUMEN
The management of urban water resources plays an important role for developing countries. The Tietê and Pinheiros Rivers (São Paulo, Brazil) are affected by domestic and industrial effluents and by the diffuse pollution. This research aimed to quantify 134 variables in the water of Tietê and Pinheiros Rivers (approximately 7,200 and 6,600 analyses, respectively) from August 2007 to December 2008. The idea was to verify if the fact that both rivers are located in the same basin is enough to consider the application of a single management plan for both. Data showed that the rivers presented significant anthropogenic interference. The results suggested that such rivers must be subjected to individual management plans since there were exclusive occurrences (variables that were only detected in one of the rivers). Moreover, there was a statistically significant difference between rainy and dry periods for eleven variables (p*<0.05, ANOVA), reinforcing the special importance of the temporal component within the monitoring program. It is expected that this study subsidize environmental recovery programs in the Tietê River, to which is recommendable to focus on prosecution of illegal wastewater releases, and in the Pinheiros River, to which special attention is suggested to the pollution derived from the pesticides load to the water body.
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Monitoreo del Ambiente/métodos , Restauración y Remediación Ambiental , Ríos/química , Contaminantes Químicos del Agua/análisis , Brasil , Estaciones del AñoRESUMEN
The management of urban water resources plays an important role for developing countries. The Tietê and Pinheiros Rivers (São Paulo, Brazil) are affected by domestic and industrial effluents and by the diffuse pollution. This research aimed to quantify 134 variables in the water of Tietê and Pinheiros Rivers (approximately 7,200 and 6,600 analyses, respectively) from August 2007 to December 2008. The idea was to verify if the fact that both rivers are located in the same basin is enough to consider the application of a single management plan for both. Data showed that the rivers presented significant anthropogenic interference. The results suggested that such rivers must be subjected to individual management plans since there were exclusive occurrences (variables that were only detected in one of the rivers). Moreover, there was a statistically significant difference between rainy and dry periods for eleven variables (p*<0.05, ANOVA), reinforcing the special importance of the temporal component within the monitoring program. It is expected that this study subsidize environmental recovery programs in the Tietê River, to which is recommendable to focus on prosecution of illegal wastewater releases, and in the Pinheiros River, to which special attention is suggested to the pollution derived from the pesticides load to the water body.
O gerenciamento dos recursos hídricos urbanos desempenha um papel importante para os países em desenvolvimento. Os rios Tietê e Pinheiros (São Paulo, Brasil) são afetados por efluentes domésticos e industriais e pela poluição difusa. Esta pesquisa teve como objetivo quantificar 134 variáveis da água dos rios Tietê e Pinheiros (aproximadamente 7.200 e 6.600 análises, respectivamente) de Agosto de 2007 a Dezembro de 2008. A ideia foi verificar se o fato de os dois rios se localizarem na mesma bacia hidrográfica é suficiente para que se considere a aplicação de um único plano de manejo para ambos. Os dados mostraram que os rios apresentam significativa interferência antrópica. Os resultados sugeriram que tais rios devem ser submetidos a planos individuais de gerenciamento, uma vez que houve ocorrências exclusivas (variáveis que foram detectadas em apenas um dos rios). Além disso, houve diferença estatisticamente significativa entre os períodos seco e chuvoso para onze variáveis (p*<0,05, ANOVA), o que reforça a especial importância da componente temporal do programa de monitoramento. Espera-se que esse estudo ofereça subsídios para programas de recuperação ambiental do rio Tietê, para o qual é recomendado foco na repressão de lançamentos clandestinos de águas residuárias, e do rio Pinheiros, para o qual se sugere especial atenção à poluição derivada do aporte de pesticidas ao corpo de água.
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Restauración y Remediación Ambiental , Monitoreo del Ambiente/métodos , Ríos/química , Contaminantes Químicos del Agua/análisis , Brasil , Estaciones del AñoRESUMEN
Obesity is associated with an increased mortality and morbidity for cardiovascular disease (CVD) and adipose tissue is recognised as an important player in obesity-mediated CVD. The diagnosis of the metabolic syndrome (MS) appears to identify substantial additional cardiovascular risk above and beyond the individual risk factors, even though the pathophysiology underlying this evidence is still unravelled. The inflammatory response related to fat accumulation may influence cardiovascular risk through its involvement not only in body weight homeostasis, but also in coagulation, fibrinolysis, endothelial dysfunction, insulin resistance (IR) and atherosclerosis. Moreover, there is evidence that oxidative stress may be a mechanistic link between several components of MS and CVD, through its role in inflammation and its ability to disrupt insulin-signaling. The cross-talk between impaired insulin-signaling and inflammatory pathways enhances both metabolic IR and endothelial dysfunction, which synergize to predispose to CVD. Persistent platelet hyperreactivity/activation emerges as the final pathway driven by intertwined interactions among IR, adipokine release, inflammation, dyslipidemia and oxidative stress and provides a pathophysiological explanation for the excess risk of atherothrombosis in this setting. Despite the availability of multiple interventions to counteract these metabolic changes, including appropriate diet, regular exercise, antiobesity drugs and bariatric surgery, relative failure to control the incidence of MS and its complications reflects both the multifactorial nature of these diseases as well as the scarce compliance of patients to established strategies. Evaluation of the impact of these therapeutic strategies on the pathobiology of atherothrombosis, as discussed in this review, will translate into an optimized approach for cardiovascular prevention.
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Enfermedades Cardiovasculares/etiología , Síndrome Metabólico/complicaciones , Obesidad/complicaciones , Animales , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Humanos , Síndrome Metabólico/sangre , Síndrome Metabólico/fisiopatología , Obesidad/sangre , Obesidad/epidemiología , Obesidad/fisiopatologíaRESUMEN
Determining reference concentrations in rivers and streams is an important tool for environmental management. Reference conditions for eutrophication-related water variables are unavailable for Brazilian freshwaters. We aimed to establish reference baselines for São Paulo State tropical rivers and streams for total phosphorus (TP) and nitrogen (TN), nitrogen-ammonia (NH(4) (+)) and Biochemical Oxygen Demand (BOD) through the best professional judgment and the trisection methods. Data from 319 sites monitored by the São Paulo State Environmental Company (2005 to 2009) and from the 22 Water Resources Management Units in São Paulo State were assessed (N = 27,131). We verified that data from different management units dominated by similar land cover could be analyzed together (Analysis of Variance, P = 0.504). Cumulative frequency diagrams showed that industrialized management units were characterized by the worst water quality (e.g. average TP of 0.51 mg/L), followed by agricultural watersheds. TN and NH(4) (+) were associated with urban percentages and population density (Spearman Rank Correlation Test, P < 0.05). Best professional judgment and trisection (median of lower third of all sites) methods for determining reference concentrations showed agreement: 0.03 & 0.04 mg/L (TP), 0.31 & 0.34 mg/L (TN), 0.06 & 0.10 mg-N/L (NH(4) (+)) and 2 & 2 mg/L (BOD), respectively. Our reference concentrations were similar to TP and TN reference values proposed for temperate water bodies. These baselines can help with water management in São Paulo State, as well as providing some of the first such information for tropical ecosystems.
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Monitoreo del Ambiente/métodos , Oxígeno/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/prevención & control , Amoníaco/análisis , Brasil , Monitoreo del Ambiente/normas , Eutrofización , Nitrógeno/análisis , Fósforo/análisis , Contaminación Química del Agua/análisis , Calidad del Agua/normasAsunto(s)
Aspirina/administración & dosificación , Angiopatías Diabéticas/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/administración & dosificación , Trombosis/prevención & control , Aspirina/efectos adversos , Medicina Basada en la Evidencia , Humanos , Inhibidores de Agregación Plaquetaria/efectos adversosRESUMEN
SUMMARY BACKGROUND: Thromboembolism is a relatively common complication of chronic heart failure (HF) and the place of antiplatelet therapy is uncertain. OBJECTIVES: We characterized the rate of thromboxane and prostacyclin biosynthesis in chronic HF of ischemic origin, with the aim of separating the influence of HF on platelet activation from that of the underlying ischemic heart disease (IHD). PATIENTS AND METHODS: We compared urinary 11-dehydro-thromboxane (TX)B(2), 2,3 dinor 6-keto-PGF(1alpha,) 8-iso-prostaglandin (PG)F(2alpha), and plasma N-terminal pro-brain natriuretic peptide (NT-pro-BNP), asymmetric dimethylarginine (ADMA), and soluble CD40 ligand (sCD40L), in 84 patients with HF secondary to IHD, 61 patients with IHD without HF and 42 healthy subjects. RESULTS: HF patients not on aspirin had significantly higher urinary 11-dehydro-TXB(2) as compared with healthy subjects (P < 0.0001) and IHD patients not on aspirin (P = 0.028). They also showed significantly higher 8-iso-PGF(2alpha) (P = 0.018), NT-pro-BNP (P = 0.021) and ADMA (P < 0.0001) than IHD patients not on aspirin. HF patients on low-dose aspirin had significantly lower 11-dehydro-TXB(2) (P < 0.0001), sCD40L (P = 0.007) and 2,3-dinor-6-keto-PGF(1alpha) (P = 0.005) than HF patients not treated with aspirin. HF patients in NYHA classes III and IV had significantly higher urinary 11-dehydro-TXB(2) than patients in classes I and II, independently of aspirin treatment (P < 0.05). On multiple linear regression analysis, higher NT-pro-BNP levels, lack of aspirin therapy and sCD40L, predicted 11-dehydro-TXB(2) excretion rate in HF patients (R(2) = 0.771). CONCLUSIONS: Persistent platelet activation characterizes HF patients. This phenomenon is related to disease severity and is largely suppressable by low-dose aspirin. The homeostatic increase in prostacyclin biosynthesis is impaired, possibly contributing to enhanced thrombotic risk in this setting.
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Aspirina/uso terapéutico , Epoprostenol/biosíntesis , Insuficiencia Cardíaca/etiología , Isquemia Miocárdica/metabolismo , Tromboxanos/biosíntesis , Anciano , Anciano de 80 o más Años , Femenino , Insuficiencia Cardíaca/metabolismo , Humanos , Masculino , Isquemia Miocárdica/complicaciones , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Chronic hyperglycemia is a major contributor to in vivo platelet activation in diabetes mellitus. OBJECTIVES: To evaluate the effects of acarbose, an alpha-glucosidase inhibitor, on platelet activation and its determinants in newly diagnosed type 2 diabetic patients. METHODS: Forty-eight subjects (26 males, aged 61 +/- 8 years) with early type 2 diabetes (baseline hemoglobin A(1c) < or = 7% and no previous hypoglycemic treatment) were randomly assigned to acarbose up to 100 mg three times a day or placebo, and evaluated every 4 weeks for 20 weeks. The main outcome measures were urinary 11-dehydro-thromboxane (TX)B(2) (marker of in vivo platelet activation) and 8-iso-prostaglandin (PG)F(2alpha) (marker of in vivo lipid peroxidation) excretion rate, 2-h postprandial plasma glucose (PPG) after a test meal, and assessment of glucose fluctuations by mean amplitude of glycemic excursions (MAGE). RESULTS: Baseline measurements revealed biochemical evidence of enhanced lipid peroxidation and platelet activation. As compared with the placebo group, patients treated with acarbose had statistically significant reductions in urinary 11-dehydro-TXB(2) and 8-iso-PGF(2alpha) excretion rate as early as after 8 weeks and at each subsequent time point (between-group P < 0.0001 at 12, 16 and 20 weeks), following earlier decreases in PPG and MAGE. Multiple regression analyses in the acarbose group revealed that PPG was the only significant predictor of 11-dehydro-TXB(2) urinary excretion rate (beta = 0.39, P = 0.002) and MAGE the only predictor of 8-iso-PGF(2alpha) urinary excretion rate (beta = 0.42, P = 0.001). CONCLUSIONS: Postprandial hyperglycemia is associated with enhanced lipid peroxidation and platelet activation in early type 2 diabetes. A moderate decrease in PPG achieved with acarbose causes time-dependent downregulation of these phenomena, suggesting a causal link between early metabolic abnormalities and platelet activation in this setting.
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Acarbosa/uso terapéutico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hiperglucemia/sangre , Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Activación Plaquetaria/efectos de los fármacos , Anciano , Arginina/análogos & derivados , Arginina/sangre , Biomarcadores/sangre , Biomarcadores/orina , Proteína C-Reactiva/metabolismo , Ligando de CD40/sangre , Diabetes Mellitus Tipo 2/orina , Dinoprost/análogos & derivados , Dinoprost/orina , Método Doble Ciego , Inhibidores Enzimáticos/uso terapéutico , Femenino , Hemoglobina Glucada/metabolismo , Inhibidores de Glicósido Hidrolasas , Humanos , Hiperglucemia/orina , Italia , Peroxidación de Lípido/efectos de los fármacos , Masculino , Persona de Mediana Edad , Selectina-P/sangre , Periodo Posprandial , Tromboxano B2/análogos & derivados , Tromboxano B2/orina , Factores de Tiempo , Resultado del TratamientoRESUMEN
CASE REPORT: A case of isolated schwannoma of the orbit, arising from the terminal branches of the abducens nerve to the lateral rectus muscle, is reported. The patient presented with a painless proptosis of the left eye. DISCUSSION: Preoperative diagnosis of benign intraorbital neoplasm was made by means of CT and MR scans; the mass was radically excised through a microsurgical lateral orbitotomy and the pathological examination revealed a schwannoma. Features of orbital schwannoma are described, together with some details concerning the surgical strategy and the history of the evolution of the lateral orbitotomy.
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Enfermedades del Nervio Abducens/patología , Nervio Abducens/patología , Neoplasias de los Nervios Craneales/patología , Neurilemoma/patología , Órbita/patología , Nervio Abducens/fisiopatología , Nervio Abducens/cirugía , Enfermedades del Nervio Abducens/fisiopatología , Enfermedades del Nervio Abducens/cirugía , Biomarcadores/análisis , Biomarcadores/metabolismo , Neoplasias de los Nervios Craneales/fisiopatología , Neoplasias de los Nervios Craneales/cirugía , Craneotomía/métodos , Humanos , Imagen por Resonancia Magnética , Masculino , Microcirugia/métodos , Persona de Mediana Edad , Neurilemoma/fisiopatología , Neurilemoma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Órbita/diagnóstico por imagen , Órbita/cirugía , Complicaciones Posoperatorias/prevención & control , Proteínas S100/análisis , Proteínas S100/metabolismo , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Arterial hypertension represents one of the most common conditions associated with an increased cardiovascular risk. New evidences support the need to adopt a global approach to the treatment of cardiovascular risk in hypertensive subjects by using drugs with proven benefits, not only for blood pressure control, but also for their pleiotropic effects. A greater understanding of the pathogenetic mechanisms of hypertension would provide a better strategy for preventing and treating this condition. Angiotensin II seems to be responsible for triggering vascular inflammation by inducing oxidative stress, resulting in up-regulation of pro-inflammatory mediators that lead to endothelial dysfunction and vascular injury. The interaction of angiotensin II, oxidative stress and endothelial dysfunction might be a target of a new integrated approach with important clinical implications.
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Antihipertensivos/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Hipertensión/tratamiento farmacológico , Angiotensina II/antagonistas & inhibidores , Antihipertensivos/administración & dosificación , Antihipertensivos/clasificación , Antihipertensivos/farmacología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Ensayos Clínicos como Asunto , Sinergismo Farmacológico , Quimioterapia Combinada , Endotelio Vascular/fisiopatología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipertensión/complicaciones , Hipolipemiantes/administración & dosificación , Hipolipemiantes/uso terapéutico , Síndrome Metabólico/tratamiento farmacológico , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/prevención & control , Estrés Oxidativo , RiesgoRESUMEN
Several distinct lines of investigation in the context of atherosclerosis dealing with low-grade inflammation, oxidative stress and platelet activation are now emerging, with CD40/CD40L system as the missing link. CD40 ligand is a transmembrane glycoprotein structurally related to tumour necrosis factor-alpha and more than 95% of the circulating CD40L derives from platelets. CD40L appears as a multiplayer of several cell types in the inflammatory network. The peculiarity of CD40L as an inflammatory mediator derived from platelets expands the functional repertoire of platelets from players of haemostasis and thrombosis to powerful amplifiers of inflammation by promoting the release of cytokines and chemokines, cell activation and cell-cell interactions. The multifunctional role of CD40L, as a simultaneous activator of all these systems, further blurs the intricate relationship between such events both in the physiological systems and the pathological derangement occurring in atherothrombosis.