276 research outputs found

    Remoção e metabolização de Dexametasona por plantas da família das macrófitas

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    A presença de compostos farmacêuticos e seus metabolitos no ambiente aquático tornou-se nos últimos anos um problema ambiental emergente. Assim, tornou-se essencial o desenvolvimento de processos de remoção mais eficientes, como o tratamento de efluentes com leitos construídos de macrófitas (LCM) que, em muitos casos, tem permitido a obtenção de águas residuais finais de boa qualidade. Este trabalho teve como objectivo avaliar a eficiência de remoção de um anti-inflamatório de origem veterinária, a dexametasona, por um microcosmos de LCM utilizando LECA 2/4 como matriz de suporte, e plantado com Phragmites australis. Preliminarmente, foi avaliada a capacidade de adsorção da dexametasona pelo material LECA, a diversas concentrações iniciais, em água e num efluente recolhido após um tratamento secundário. A LECA demonstrou elevada capacidade de remoção da dexametasona, quer em água quer em efluente, embora neste último meio se tenha verificado um ligeira diminuição na eficiência de remoção (∼2 %). Posteriormente foi avaliada a eficiência de remoção da dexametasona alcançada pelo microcosmos de LCM, em dois ensaios realizados em estações do ano opostas (Inverno e Verão), a qual se verificou ter sido muito elevada (∼80 %) podendo a maior parte da eficiência ser atribuída à matriz de suporte através de fenómenos de adsorção. No entanto, comparando as remoções alcançadas em leitos plantados e não-plantados verificou-se que as plantas permitiram acelerar significativamente o processo de remoção. As amostras de tecidos de folhas das plantas usadas nos ensaios foram analisadas por LC-ESI-MS, tendo sido possível constatar a presença de DEXA e de dois dos seus metabolitos, o que sugere que a DEXA é absorvida e translocada para a parte área da planta, sofrendo uma rápida metabolização/transformação (num período inferior a 48h). Os resultados deste estudo apontam para o potencial de utilização dos LCMs, tendo LECA como matriz de suporte e plantados com Phragmites australis, para a remoção de DEXA de efluentes contaminados com este anti-inflamatório de origem veterinária

    Methodology for Abrasive Wear Evaluation in Elevator Stage Centrifugal Pump Impellers

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    The abrasion resistance of the impellers depends on the characteristics of the materials used in their manufacture. In this work, a methodology is proposed for the evaluation of the abrasive wear of the plates of the centrifugal pump impellers, used in the gross water infrastructure station (GWIS) of sedimentary rivers, due to the sediment load variation and the river fluviometric dimension. In order to determine the wear mode and the relationship of the material-specific wear coefficient (K), due to the sediment concentration, a rotating ball abrasometer test was performed on SAE 8620, gray cast iron (GCI), and nodular cast iron (NCI), used in the manufacture of impellers. As an abrasive suspension, the concentrations of 1, 2, 3, 5, and 10 g L−1 of sediment were used in distilled water. The wear volume as a function of the relative velocity of the mixture in relation to the impeller blades was estimated mathematically. The results show that: i) The abrasive capacity of the sediments in different concentrations; ii) SAE 8620 steel was more resistant to abrasive wear; and iii) the rotational control of the pump as a function of sediment concentration and river level showed the possibility of reducing wear by 30%

    Artrite reumatóide e doença cardiovascular na atualidade: o que sabemos sobre essa associação e o que podemos fazer pelo paciente?

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    The interest in auto-immune diseases has been grown, mainly about cardiovascular illnesses. Rheumatoid arthritis has been considered an independent risk factor for coronary arterial disease in last years. Recently, different studies have been performed in order to better clarify crucial points in risk stratification and correct treatment for patients with rheumatoid arthritis. New specific therapies have been studying and promising reduction of cardiovascular risk. Thereby, we made a bibliographic revision to show the importance of atherosclerotic and inflammatory mechanisms in coronary artery disease. Furthermore, we suggested different strategies to establish risk stratification and treatment of cardiovascular diseases in patients with rheumatoid arthritis.O interesse em doenças auto-imunes vem crescendo a cada ano, principalmente sobre sua relação com doenças cardiovasculares.Especificamente a artrite reumatóide vem sendo considerada um fator de risco independente para doença arterial coronária nos últimos anos. Diversos estudos foram realizados recentemente com o objetivo de esclarecer pontos cruciais na estratificação de risco desses pacientes e no seu respectivo tratamentomedicamentoso adequado. Novas terapias específicas da doença reumatóide ainda estão em estudo, e prometem reduzir o risco cardiovascular a longo prazo. Desse modo, realizamos uma revisão bibliográfica ampla, utilizando as principais bases de dados nacionais e internacionais, com o objetivo de salientar a importância de mecanismos ateroscleróticos e inflamatórios sobre a doença arterial coronária. Além disso, frente às atuais evidências, sugerimos estratégias de estratificação de risco e tratamento da doença arterial coronária em pacientes com artrite reumatóide

    Post-mortem diagnosis of acute myocardial infarction in patients with acute respiratory failure - demographic, etiologic and histological pulmonary analysis

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    Introduction: Acute respiratory failure (ARF) is present in 5% of the patients with acute myocardial infarction (AMI) and is responsible for 20% to 30% of the mortality post-AMI. It is unclear the role of inflammation correlated with pulmonary edema (PE) as a cause of ARF post-AMI. Objectives: Describe the demographic, etiologic data and histological pulmonary findings in autopsies of patients dead due to ARF with non-diagnosis AMI during life between 1,990 and 2,008. Methods: This study considers 4,223 autopsies of patients who died of ARF without cause of death related during life. The diagnosis of AMI was performed in 218 (4.63%) patients, and were obtained: age, sex and major associated diseases. Pulmonary histopathology was categorized as: diffuse alveolar damage (DAD); pulmonary edema (PE); alveolar hemorrhage (AH);and lympho-plamacytic interstitial pneumonia (LPIP). Odds ratio of AMI developing specific histopathology was determined by logistic regression. Results: Were observed 147 men and mean age was 64 years. Pulmonary histopathology showed, in descending order: PE (72.9%), DAD, LPIP and HA. Bacterial bronchopneumonia was present in 11.9%, systemic arterial hypertension in 10.1%, dilated cardiomyopathy in 6.9%, pulmonary embolism in 6.0%, hypertrophic cardiomyopathy in 4.6%, chronic obstructive pulmonary disease in 3.7% and diabetes mellitus in 3.7% of patients. Multivariate analysis demonstrated significantly positive association of IAM with PE and with DAD. Conclusions: For the first time we demonstrated that in autopsies of patients with ARF as cause of death, the diagnosis of AMI was present in about 5%. We observed important inflammatory response in pulmonary histology as never suggested beforeIntrodução: A insuficiência respiratória aguda (IRA) está presente em 5% dos pacientes com infarto agudo do miocárdio (IAM) e é associada à mortalidade de 20% a 30% nesses pacientes. Não está claro o papel da inflamação relacionada ao edema agudo de pulmão (EAP) na gênese da IRA pós IAM. Objetivos: Descrever os dados demográficos, etiológicos e os achados histológicos pulmonares em autópsias realizadas uentre 1990 e 2008, de pacientes que morreram por IRA, sem diagnóstico in-vivo de IAM. Métodos: Este estudo considerou 4223 autópsias de pacientes que morreram de IRA nos quais só foi definida post-mortem sua causa de morte. O diagnóstico de IAM foi feito por autópsia em 218 (4,63%) pacientes, dos quais foram obtidos: idade, sexo e principais doenças associadas. Os achados pulmonares histológicos foram classificados em: dano alveolar difuso (DAD), edema agudo de pulmão (EAP), hemorragia alveolar (HA) e pneumonia intersticial linfo-plasmocitária (PILP). A probabilidade de IAM desenvolver determinado tipo de achado histopatológico pulmonar foi calculada por regressão logística. Resultados: Foram observados 147 homens, e a mediana de idade foi 64 anos. A análise histopatológica pulmonar mostrou, em ordem decrescente: EAP (72,9%), DAD, PILP e HIA. Broncopneumonia bacteriana esteve presente em 11,9%, hipertensão arterial sistêmica em 10,1%, miocardiopatia dilatada em 6,9%, tromboembolismo pulmonar em 6,0%, cardiomiopatia hipertrófica em 4,6%, doença pulmonar obstrutiva crônica em 3,7% e diabetes mellitus em 3,7% dos pacientes. A análise multivariada demonstrou associação significativamente positiva de IAM com EAP e DAD. Conclusões: Pela primeira vez na literatura, demonstramos, por meio de autópsias, que em pacientes com IRA que evoluem à óbito sem diagnóstico estabelecido, IAM esteve presente em aproximadamente 5% dos casos. Nós observamos importante componente inflamatório na histologia pulmonar, nunca antes sugerid

    Manifestações clínicas e análise histopatológica pulmonar relacionadas a diferentes doenças em pacientes com tromboembolismo pulmonar fatal – um estudo em autópsias

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    Introdução: Tromboembolismo pulmonar (TEP) é uma das mais graves complicações dentre pacientes hospitalizados e permanece subdiagnosticado. Ainda hoje, sua fisiopatologia não está completamente elucidada. Objetivos: Correlacionar comorbidades, neoplasias, cirurgias e achados histológicos às manifestações clínicas associadas ao TEP. Métodos: Entre 2001 a 2008, foram revisadas 291 autópsias de pacientes cuja causa de morte foi TEP. Os seguintes dados foram obtidos: idade, sexo, manifestações clínicas, achados histológicos e principais doenças de base/comorbidades, neoplasias e cirurgias da última internação. Os achados histológicos foram categorizados em: dano alveolar difuso (DAD), edema agudo de pulmão (EAP), hemorragia intra-alveolar (HIA) e pneumonia intersticial linfo-plasmocítica (PILP). Odds ratios foram obtidas por regressão logística e foram consideradassignificativas quando p < 0,05. Resultados: A mediana de idade foi 64 anos. Cerca de 64% dos pacientes apresentava doenças cardiovasculares.O achado pulmonar mais prevalente foi EAP. Apenas 13% dos casos apresentaram suspeita clínica. Insuficiência respiratória esteve associada a EAP, HIA e DAD; assim como instabilidade hemodinâmica a HIA e DAD. Conclusões:Foram encontradas importantes associações entre achados clínicos e histológicos em pacientes com TEP. A compreensão dos mecanismos fisiopatológicos envolvidos com cada doença associada a TEP pode auxiliar no diagnóstico e no tratamento da doença.Introduction: Pulmonary thromboembolism (PTE) is one of the most fatal complications among hospitalized patients and remains undiagnosed. Its physiopathology and its epidemiology aren’t widely known in literature. Objectives: To correlate underlying diseases, different cancers and surgeries to histological findings and in-vivo manifestations associated to fatal PTE from autopsy reports. Methods: From 2,001 to 2,008, were reviewed 291 autopsies of patients whose cause of death was PTE. The following data were obtained: age, sex, clinical in-vivo manifestations, post-mortem pathological patterns and main associated underlying diseases, cancers and surgeries performed in last hospitalization. The pulmonary histopathological changes were categorized in: diffuse alveolar damage (DAD), pulmonary edema (PE), alveolar hemorrhage (AH) and lympho/plasmacytic interstitial pneumonia (LPIP). Odds ratios of positive relations were obtained by logistic regression and were considered significative when p < 0.05. Results: The median age was 64 years. 64% of patients presented cardiovascular illness associated to PTE. The most prevalent pulmonary finding was PE. Only 13% of cases had clinical suspect. Acute respiratory failure was positively related to PE, AH and DAD; as well hemodynamic instability to AH and DAD. Conclusions: We found important relations between clinical data and histological findings of fatal PTE patients. The understanding of pulmonary physiopathological mechanism involved with each PTE-associated disease can improve diagnosis in order to offer prompt treatment and reduce mortality

    Zika virus pathogenesis in rhesus macaques is unaffected by pre-existing immunity to dengue virus

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    Zika virus (ZIKV) is a re-emerging virus that has recently spread into dengue virus (DENV) endemic regions and cross-reactive antibodies (Abs) could potentially affect ZIKV pathogenesis. Using DENV-immune serum, it has been shown in vitro that antibody-dependent enhancement (ADE) of ZIKV infection can occur. Here we study the effects of pre-existing DENV immunity on ZIKV infection in vivo. We infect two cohorts of rhesus macaques with ZIKV; one cohort has been exposed to DENV 2.8 years earlier and a second control cohort is naïve to flaviviral infection. Our results, while confirming ADE in vitro, suggest that pre-existing DENV immunity does not result in more severe ZIKV disease. Rather our results show a reduction in the number of days of ZIKV viremia compared to naïve macaques and that the previous exposure to DENV may result in modulation of the immune response without resulting in enhancement of ZIKV pathogenesis

    Activity of the antiarrhythmic drug amiodarone against Leishmania (L.) infantum: an in vitro and in vivo approach

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    <div><p>Abstract Background: Considering the high toxicity and limited therapies available for treating visceral leishmaniasis (VL), the drug repositioning approach represents a faster way to deliver new therapies to the market. Methods: In this study, we described for the first time the activity of a potent antiarrhythmic, amiodarone (AMD), against L. (L.)infantum and its in vitro and in vivo activity. Results: The evaluation against promastigotes has shown that amiodarone presents leishmanicidal effect against the extracellular form, with an IC50 value of 10 μM. The activity was even greater against amastigotes in comparison with promastigotes with an IC50 value of 0.5 μM. The selectivity index in relation to the intracellular form demonstrated that the antiparasitic activity was approximately 56 times higher than its toxicity to mammalian cells. Investigation of the in vivo AMD activity in the L. infantum-infected hamster model showed that 51 days after the initial infection, amiodarone was unable to reduce the parasite burden in the spleen and liver when treated for 10 consecutive days, intraperitoneally, at 50 mg/kg/day, as determined by qPCR. Although not statistically significant, AMD was able to reduce the parasite burden by 20% in the liver when treated for 10 consecutive days, orally, at 100 mg/kg/day; no reduction in the spleen was found by qPCR. Conclusions: Our findings may help further drug design studies seeking new AMD derivatives that may provide new candidates with an in vitro selectivity close to or even greater than that observed in the prototype delivering effectiveness in the experimental model of VL.</p></div

    Measurement of CNGS muon neutrino speed with Borexino

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    We have measured the speed of muon neutrinos with the Borexino detector using short-bunch CNGS beams. The final result for the difference in time-of-flight between a =17 GeV muon neutrino and a particle moving at the speed of light in vacuum is {\delta}t = 0.8 \pm 0.7stat \pm 2.9sys ns, well consistent with zero.Comment: 6 pages, 5 figure

    Precision measurement of the neutrino velocity with the ICARUS detector in the CNGS beam

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    During May 2012, the CERN-CNGS neutrino beam has been operated for two weeks for a total of 1.8 10^17 pot in bunched mode, with a 3 ns narrow width proton beam bunches, separated by 100 ns. This tightly bunched beam structure allows a very accurate time of flight measurement of neutrinos from CERN to LNGS on an event-by-event basis. Both the ICARUS-T600 PMT-DAQ and the CERN-LNGS timing synchronization have been substantially improved for this campaign, taking ad-vantage of additional independent GPS receivers, both at CERN and LNGS as well as of the deployment of the "White Rabbit" protocol both at CERN and LNGS. The ICARUS-T600 detector has collected 25 beam-associated events; the corresponding time of flight has been accurately evaluated, using all different time synchronization paths. The measured neutrino time of flight is compatible with the arrival of all events with speed equivalent to the one of light: the difference between the expected value based on the speed of light and the measured value is tof_c - tof_nu = (0.10 \pm 0.67stat. \pm 2.39syst.) ns. This result is in agreement with the value previously reported by the ICARUS collaboration, tof_c - tof_nu = (0.3 \pm 4.9stat. \pm 9.0syst.) ns, but with improved statistical and systematic errors.Comment: 21 pages, 13 figures, 1 tabl

    Plant communities as a tool in temporary ponds conservation in SW Portugal

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    Pond conservationTemporary ponds are seasonal wetlands annually subjected to extreme and unstable ecological conditions, neither truly aquatic nor truly terrestrial. This habitat and its flora have been poorly studied and documented because of the ephemeral character of the flora, the changeable annual weather that has a great effect on the small, herbaceous taxa and the declining abundance of temporary ponds. The objectives of this study are: (a) to define plant community diversity in terms of floristic composition of ephemeral wetlands in SW Portugal, (b) to identify temporary pond types according to their vegetation composition and (c) to identify those ponds that configure the European community priority habitat (3170* – Mediterranean temporary ponds). Vegetation sampling was conducted in 29 ponds, identifying 168 species grouped among 15 plant communities. Soil texture, pH, organic C and N content were measured, but only N and percent of clay appear to be related with the distribution of each community type. The results showed that ephemeral wetlands could be classified into four type: vernal pools, marshlands, deep ponds and disturbed wetlands. Vernal pools correspond to the Mediterranean temporary ponds (3170*), protected as priority habitat under the EU Habitats Directive. Submersed Isoetes species (Isoetes setaceum and Isoetes velatum) represents, together with Eryngium corniculatum, the indicator species for vernal pools. We identify also indicator plant communities of this priority habitat, namely I. setaceum and E. corniculatum– Baldellia ranunculoides plant communities. In this region, the conservation of temporary ponds has so far been compatible with traditional agricultural activities, but today these ponds are endangered by the intensification of agriculture and the loss of traditional land use practices and by the development of touris
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