71 research outputs found
Efeito da filtração de ostras (Magallana gigas), em cultivos multitróficos integrados na ocorrência do parasita Amyloodinium ocellatum
A produção em aquacultura e a variedade de espécies cultivadas aumentaram drasticamente nas últimas duas décadas, devido à necessidade de alimentar uma população mundial em constante crescimento. Esta produção de peixes intensiva leva a que ocorram mais frequentemente doenças tanto infeções bacterianas, virais, parasitárias e/ou fúngicas.
A amiloodiniose é uma doença parasitária causada pelo dinoflagelado Amyloodinium ocellatum. É um dinoflagelado eurialino que parasita uma ampla variedade de peixes estuarinos e marinhos. O ciclo de vida do parasita consiste em 3 estágios: o trofonte caracterizado pelo estágio de alimentação, o tomonte caracterizado pela fase de cisto, e o dinósporo caracterizado pelo estágio infecioso que adere à s brânquias e pele do hospedeiro. Os sinais clÃnicos de incluem anorexia, dispneia, hiperplasia, inflamação, hemorragia e necrose. O A. ocellatum é transmitido através do contato direto com dinósporos vivos. Os métodos principais de diagnóstico baseiam-se na identificação de tecidos infetados ao microscópio. Para um diagnóstico mais completo, embora dispendioso, recorre-se a técnicas moleculares, como o PCR para a deteção de baixas concentrações do parasita. Esta técnica pode ainda ser considerada como um método de monitorização e controlo de doenças.
Os cultivos IMTA são mais sustentáveis porque são cultivadas várias espécies simultaneamente reduzindo o excesso de nutrientes que iriam para o meio aquático, trazendo um maior rendimento económico para os produtores. No caso dos moluscos bivalves, as espécies normalmente usadas nestes sistemas IMTA, a ostra do PacÃfico, Magallana gigas, é um importante bivalve cultivado em todo o mundo com interesse económico. Os bivalves filtram e retêm uma imensa quantidade de microrganismos presentes na água das zonas de produção como por exemplo bactérias, fitoplâncton e parasitas que ficam retidos nas brânquias, estômago e glândula digestiva das mesmas. Colocando-se a questão se as ostras filtram o A. ocellatum. Posto isto este trabalho vem recolher informação para auxiliar os produtores de aquacultura, que têm perdas económicas grandes devido a este parasita.
Os objetivos principais do estudo são perceber se as ostras poderiam ser usadas como um filtro natural ou se por outro lado atuavam como um vetor de propagação do parasita, e perceber ainda se os dinósporos afetavam os tecidos das ostras e a nÃvel imunológico.
Para isto, usaram-se 144 ostras divididas em dois tratamentos, o controlo (sem parasita) e o infetado (com parasita). Ao longo do ensaio foram recolhidas amostras, nos momentos 0h, 3h, 24h, 96h e 7dias, para análise de parâmetros de resposta imune, histológica, expressão genética e confirmação por PCR.
De acordo com os resultados apresentados pode-se concluir que as ostras são um vetor de propagação do parasita A. ocellatum representando um perigo para as aquaculturas de policultivos, e tem de existir medidas no combate do mesmo, pois representa um grande problema para o setor. Futuramente à uma necessidade de responder a muitas questões que este estudo levantou com os resultados obtidos.Aquaculture production and the variety of species farmed have increased dramatically over the last two decades due to the need to feed a constantly growing world population. This intensive fish production leads to more frequent occurrence of diseases either bacterial, viral, parasitic and/or fungal infections.
Amyloodiniosis is a parasitic disease caused by the dinoflagellate Amyloodinium ocellatum. It is a eurialine dinoflagellate that parasitizes a wide variety of estuarine and marine fish. The life cycle of the parasite consists of 3 stages: the trophon characterized by the feeding stage, the tomon characterized by the cyst stage, and the dinospore characterized by the infective stage that adheres to the gills and skin of the host. Clinical signs of include anorexia, dyspnea, hyperplasia, inflammation, hemorrhage, and necrosis. A. ocellatum is transmitted through direct contact with live dinospores. The main methods of diagnosis are based on the identification of infected tissue under the microscope. For a more complete, but expensive diagnosis, molecular techniques, such as PCR for the detection of low concentrations of the parasite, are used. This technique can also be considered as a method of disease monitoring and control.
IMTA cultures are more sustainable because several species are cultivated simultaneously, reducing the excess nutrients that would go into the aquatic environment, bringing greater economic return to the producers. In the case of bivalve mollusks, the species commonly used in these IMTA systems, the Pacific oyster, Magallana gigas, is an important bivalve cultured worldwide with economic interest. Bivalves filter and retain an immense amount of microorganisms present in the water of the production areas such as bacteria, phytoplankton and parasites that are retained in their gills, stomach and digestive gland. The question arises if oysters filter A. ocellatum. Therefore, this work will collect information to help aquaculture producers, who have large economic losses due to this parasite.
The main objectives of the study were to understand if oysters could be used as a natural filter or if they acted as a vector for the spread of the parasite, and to understand if the dinospores affected the tissues of the oysters at the immunological level.
This was done using 144 oysters divided into two treatments, control (without parasite) and infected (with parasite). Throughout the trial, samples were collected at 0h, 3h, 24h, 96h and 7days for analysis of immune response parameters, histology, gene expression and PCR confirmation.
According to the results presented, it can be concluded that oysters are a vector for the spread of the parasite A. ocellatum, representing a danger for polyculture aquacultures, and there must be measures to combat it, as it represents a major problem for the sector. In the future there is a need to answer many of the questions that this study has raised with the results obtained
Doença trombótica das veias e seios venosos cerebrais
Tese de doutoramento, Medicina (Neurologia), Universidade de Lisboa, Faculdade de Medicina, 2009DisponÃvel no document
Case Report
We report a case of a cerebral venous thrombosis (CVT) in a chronic kidney disease patient with three CVT predisposing conditions. A 53 year-old woman on chronic peritoneal dialysis presented to the emergency
department with acute headache and vertigo. The neurological examination and head CT scan performed at
the emergency department were normal but, three days later, a lateral gait deviation and a horizontal nystagmus were identified. A brain MRI and MRI-venogram confirmed a left lateral sinus thrombosis. Hormonal
replacement therapy (HRT), a positive lupus anticoagulante and a homozygous mutation on the methylenetetrahydrofolate reductase gene, with hyperhomocysteinaemia, were the three well-known prothrombotic conditions identified in this patient. HRT was discontinued, the patient started anticoagulation with warfarin and folic acid supplementation and was discharged, 10 days after admission, complaining of a mild vertigo. After six months of therapy the patient had vertigo improvement and maintained a positive lupus
anticoagulant. The head MRI and MRI-venography showed a thrombus reduction.info:eu-repo/semantics/publishedVersio
Toward a Microencapsulated 3D hiPSC-Derived in vitro Cardiac Microtissue for Recapitulation of Human Heart Microenvironment Features
SAICTPAC/0047/2015 PTDC/BTMSAL/32566/ 2017 PTDC/MEC-CAR/29590/2017 UIDB/04462/2020 UIDP/04462/2020 H2020, ID:874827 SFRH/BD/52475/2013 SFRH/BPD/120595/2016The combination of cardiomyocytes (CM) and non-myocyte cardiac populations, such as endothelial cells (EC), and mesenchymal cells (MC), has been shown to be critical for recapitulation of the human heart tissue for in vitro cell-based modeling. However, most of the current engineered cardiac microtissues still rely on either (i) murine/human limited primary cell sources, (ii) animal-derived and undefined hydrogels/matrices with batch-to-batch variability, or (iii) culture systems with low compliance with pharmacological high-throughput screenings. In this work, we explored a culture platform based on alginate microencapsulation and suspension culture systems to develop three-dimensional (3D) human cardiac microtissues, which entails the co-culture of human induced pluripotent stem cell (hiPSC) cardiac derivatives including aggregates of hiPSC–CM and single cells of hiPSC–derived EC and MC (hiPSC–EC+MC). We demonstrate that the 3D human cardiac microtissues can be cultured for 15 days in dynamic conditions while maintaining the viability and phenotype of all cell populations. Noteworthy, we show that hiPSC–EC+MC survival was promoted by the co-culture with hiPSC–CM as compared to the control single-cell culture. Additionally, the presence of the hiPSC–EC+MC induced changes in the physical properties of the biomaterial, as observed by an increase in the elastic modulus of the cardiac microtissue when compared to the hiPSC–CM control culture. Detailed characterization of the 3D cardiac microtissues revealed that the crosstalk between hiPSC–CM, hiPSC–EC+MC, and extracellular matrix induced the maturation of hiPSC–CM. The cardiac microtissues displayed functional calcium signaling and respond to known cardiotoxins in a dose-dependent manner. This study is a step forward on the development of novel 3D cardiac microtissues that recapitulate features of the human cardiac microenvironment and is compliant with the larger numbers needed in preclinical research for toxicity assessment and disease modeling.publishersversionpublishe
Seizures, electroencephalographic abnormalities, and outcome of ischemic stroke patients
© 2017 The Authors. Epilepsia Open published by Wiley Periodicals Inc. on behalf of International League Against Epilepsy. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial, and no modifications or adaptations are made.Objective: Seizures and electroencephalographic (EEG) abnormalities have been associated with unfavorable stroke functional outcome. However, this association may depend on clinical and imaging stroke severity. We set out to analyze whether epileptic seizures and early EEG abnormalities are predictors of stroke outcome after adjustment for age and clinical/imaging infarct severity.
Methods: A prospective study was made on consecutive and previously independent acute stroke patients with a National Institutes of Health Stroke Scale (NIHSS) score ≥ 4 on admission and an acute anterior circulation ischemic lesion on brain imaging. All patients underwent standardized clinical and diagnostic assessment during admission and after discharge, and were followed for 12 months. Video-EEG (<60 min) was performed in the first 72 h. The Alberta Stroke Program Early CT Score quantified middle cerebral artery infarct size. The outcomes in this study were an unfavorable functional outcome (modified Rankin Scale [mRS] ≥ 3) and death (mRS = 6) at discharge and 12 months after stroke.
Results: Unfavorable outcome at discharge was independently associated with NIHSS score (p = 0.001), EEG background activity slowing (p < 0.001), and asymmetry (p < 0.001). Unfavorable outcome 1 year after stroke was independently associated with age (p = 0.001), NIHSS score (p < 0.001), remote symptomatic seizures (p = 0.046), EEG background activity slowing (p < 0.001), and asymmetry (p < 0.001). Death in the first year after stroke was independently associated with age (p = 0.028), NIHSS score (p = 0.001), acute symptomatic seizures (p = 0.015), and EEG suppression (p = 0.019).
Significance: Acute symptomatic seizures were independent predictors of vital outcome and remote symptomatic seizures of functional outcome in the first year after stroke. Therefore, their recognition and prevention strategies may be clinically relevant. Early EEG abnormalities were independent predictors and comparable to age and early clinical/imaging infarct severity in stroke functional outcome discrimination, reflecting the concept that EEG is a sensitive and robust method in the functional assessment of the brain.This work was supported by the 2012 Research Grant in Cerebrovascular Diseases (C.B.; scientific promoter: Sociedade Portuguesa do AVC; sponsor: Tecnifar).info:eu-repo/semantics/publishedVersio
One-Year Risk of Stroke after Transient Ischemic Attack or Minor Stroke
BACKGROUND Previous studies conducted between 1997 and 2003 estimated that the risk of stroke or an acute coronary syndrome was 12 to 20% during the first 3 months after a transient ischemic attack (TIA) or minor stroke. The TIAregistry.org project was designed to describe the contemporary profile, etiologic factors, and outcomes in patients with a TIA or minor ischemic stroke who receive care in health systems that now offer urgent evaluation by stroke specialists.
METHODS We recruited patients who had had a TIA or minor stroke within the previous 7 days. Sites were selected if they had systems dedicated to urgent evaluation of patients with TIA. We estimated the 1-year risk of stroke and of the composite outcome of stroke, an acute coronary syndrome, or death from cardiovascular causes. We also examined the association of the ABCD2 score for the risk of stroke (range, 0 [lowest risk] to 7 [highest risk]), findings on brain imaging, and cause of TIA or minor stroke with the risk of recurrent stroke over a period of 1 year.
RESULTS From 2009 through 2011, we enrolled 4789 patients at 61 sites in 21 countries. A total of 78.4% of the patients were evaluated by stroke specialists within 24 hours after symptom onset. A total of 33.4% of the patients had an acute brain infarction, 23.2% had at least one extracranial or intracranial stenosis of 50% or more, and 10.4% had atrial fibrillation. The Kaplan–Meier estimate of the 1-year event rate of the composite cardiovascular outcome was 6.2% (95% confidence interval, 5.5 to 7.0). Kaplan–Meier estimates of the stroke rate at days 2, 7, 30, 90, and 365 were 1.5%, 2.1%, 2.8%, 3.7%, and 5.1%, respectively. In multivariable analyses, multiple infarctions on brain imaging, large-artery atherosclerosis, and an ABCD2 score of 6 or 7 were each associated with more than a doubling of the risk of stroke.
CONCLUSIONS We observed a lower risk of cardiovascular events after TIA than previously reported. The ABCD2 score, findings on brain imaging, and status with respect to large-artery atherosclerosis helped stratify the risk of recurrent stroke within 1 year after a TIA or minor stroke. (Funded by Sanofi and Bristol-Myers Squibb.)Supported by an unrestricted grant from Sanofi and Bristol-Myers Squibb
Stroke frequency, associated factors, and clinical features in primary systemic vasculitis: a multicentric observational study
Objectives: The cerebral vessels may be affected in primary systemic vasculitis (PSV), but little is known about cerebrovascular events (CVEs) in this population. This study aimed to determine the frequency of CVEs at the time of diagnosis of PSV, to identify factors associated with CVEs in PSV, and to explore features and outcomes of stroke in patients with PSV. Methods: Data from adults newly diagnosed with PSV within the Diagnostic and Classification Criteria in VASculitis (DCVAS) study were analysed. Demographics, risk factors for vascular disease, and clinical features were compared between patients with PSV with and without CVE. Stroke subtypes and cumulative incidence of recurrent CVE during a prospective 6-month follow-up were also assessed. Results: The analysis included 4828 PSV patients, and a CVE was reported in 169 (3.50%, 95% CI 3.00–4.06): 102 (2.13% 95% CI 1.73–2.56) with stroke and 81 (1.68% 95% CI 1.33–2.08) with transient ischemic attack (TIA). The frequency of CVE was highest in Behçet’s disease (9.5%, 95% CI 5.79–14.37), polyarteritis nodosa (6.2%, 95% CI 3.25–10.61), and Takayasu’s arteritis (6.0%, 95% CI 4.30–8.19), and lowest in microscopic polyangiitis (2.2%, 95% CI 1.09–3.86), granulomatosis with polyangiitis (2.0%, 95% CI 1.20–3.01), cryoglobulinaemic vasculitis (1.9%, 95% CI 0.05–9.89), and IgA-vasculitis (Henoch-Schönlein) (0.4%, 95% CI 0.01–2.05). PSV patients had a 11.9% cumulative incidence of recurrent CVE during a 6-month follow-up period. Conclusion: CVEs affect a significant proportion of patients at time of PSV diagnosis, and the frequency varies widely among different vasculitis, being higher in Behçet’s. Overall, CVE in PSV is not explained by traditional vascular risk factors and has a high risk of CVE recurrence
Towards the genetic basis of cerebral venous thrombosis-the BEAST Consortium: a study protocol.
INTRODUCTION:
Cerebral venous thrombosis (CVT) is a rare cerebrovascular condition accounting for <1% of all stroke cases and mainly affects young adults. Its genetic aetiology is not clearly elucidated.
METHODS AND ANALYSIS:
To better understand the genetic basis of CVT, we have established an international biobank of CVT cases, Biorepository to Establish the Aetiology of Sinovenous Thrombosis (BEAST) which aims to recruit highly phenotyped cases initially of European descent and later from other populations. To date we have recruited 745 CVT cases from 12 research centres. As an initial step, the consortium plans to undertake a genome-wide association analysis of CVT using the Illumina Infinium HumanCoreExome BeadChip to assess the association and impact of common and low-frequency genetic variants on CVT risk by using a case-control study design. Replication will be performed to confirm putative findings. Furthermore, we aim to identify interactions of genetic variants with several environmental and comorbidity factors which will likely contribute to improve the understanding of the biological mechanisms underlying this complex disease.
ETHICS AND DISSEMINATION:
BEAST meets all ethical standards set by local institutional review boards for each of the participating sites. The research outcomes will be published in international peer-reviewed open-access journals with high impact and visibility. The results will be presented at national and international meetings to highlight the contributions into improving the understanding of the mechanisms underlying this uncommon but important disease. This international DNA repository will become an important resource for investigators in the field of haematological and vascular disorders
Coma in adult cerebral venous thrombosis:The BEAST study
Background and purpose: Coma is an independent predictor of poor clinical outcomes in cerebral venous thrombosis (CVT). We aimed to describe the association of age, sex, and radiological characteristics of adult coma patients with CVT. Methods: We used data from the international, multicentre prospective observational BEAST (Biorepository to Establish the Aetiology of Sinovenous Thrombosis) study. Only positively associated variables with coma with <10% missing data in univariate analysis were considered for the multivariate logistic regression model. Results: Of the 596 adult patients with CVT (75.7% women), 53 (8.9%) patients suffered coma. Despite being a female-predominant disease, the prevalence of coma was higher among men than women (13.1% vs. 7.5%, p = 0.04). Transverse sinus thrombosis was least likely to be associated with coma (23.9% vs. 73.3%, p < 0.001). The prevalence of superior sagittal sinus thrombosis was higher among men than women in the coma sample (73.6% vs. 37.5%, p = 0.01). Men were significantly older than women, with a median (interquartile range) age of 51 (38.5–60) versus 40 (33–47) years in the coma (p = 0.04) and 44.5 (34–58) versus 37 (29–48) years in the non-coma sample (p < 0.001), respectively. Furthermore, an age-and superior sagittal sinus-adjusted multivariate logistic regression model found male sex (odds ratio = 1.8, 95% confidence interval [CI] = 1.0–3.4, p = 0.04 to be an independent predictor of coma in CVT, with an area under the receiver operating characteristic curve of 0.61 (95% CI = 0.52–0.68, p = 0.01). Conclusions: Although CVT is a female-predominant disease, men were older and nearly twice as likely to suffer from coma than women
Stroke frequency, associated factors, and clinical features in primary systemic vasculitis: A multicentric observational study
Objectives: The cerebral vessels may be affected in primary systemic vasculitis (PSV), but little is known about cerebrovascular events (CVEs) in this population. This study aimed to determine the frequency of CVEs at the time of diagnosis of PSV, to identify factors associated with CVEs in PSV, and to explore features and outcomes of stroke in patients with PSV. Methods: Data from adults newly diagnosed with PSV within the Diagnostic and Classification Criteria in VASculitis (DCVAS) study were analysed. Demographics, risk factors for vascular disease, and clinical features were compared between patients with PSV with and without CVE. Stroke subtypes and cumulative incidence of recurrent CVE during a prospective 6-month follow-up were also assessed. Results: The analysis included 4828 PSV patients, and a CVE was reported in 169 (3.50%, 95% CI 3.00–4.06): 102 (2.13% 95% CI 1.73–2.56) with stroke and 81 (1.68% 95% CI 1.33–2.08) with transient ischemic attack (TIA). The frequency of CVE was highest in Behçet’s disease (9.5%, 95% CI 5.79–14.37), polyarteritis nodosa (6.2%, 95% CI 3.25–10.61), and Takayasu’s arteritis (6.0%, 95% CI 4.30–8.19), and lowest in microscopic polyangiitis (2.2%, 95% CI 1.09–3.86), granulomatosis with polyangiitis (2.0%, 95% CI 1.20–3.01), cryoglobulinaemic vasculitis (1.9%, 95% CI 0.05–9.89), and IgA-vasculitis (Henoch-Schönlein) (0.4%, 95% CI 0.01–2.05). PSV patients had a 11.9% cumulative incidence of recurrent CVE during a 6-month follow-up period. Conclusion: CVEs affect a significant proportion of patients at time of PSV diagnosis, and the frequency varies widely among different vasculitis, being higher in Behçet’s. Overall, CVE in PSV is not explained by traditional vascular risk factors and has a high risk of CVE recurrence
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