Browsing by Author "Silva, Ana"
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- Co-activation of upper limb muscles during reaching in post-stroke subjects: An analysis of the contralesional and ipsilesional limbsPublication . Silva, Cláudia; Silva, Augusta; Pinheiro De Sousa, Andreia Sofia; Pinheiro, Ana Rita; Bourlinova, Catarina; Silva, Ana; Salazar, António; Borges, Carla; Crasto, Carlos; Correia, Miguel Velhote; Vilas-Boas, João Paulo; Santos, RubimThe purpose of this study was to analyze the change in antagonist co-activation ratio of upper-limb muscle pairs, during the reaching movement, of both ipsilesional and contralesional limbs of post-stroke subjects. Nine healthy and nine post-stroke subjects were instructed to reach and grasp a target, placed in the sagittal and scapular planes of movement. Surface EMG was recorded from postural control and movement related muscles. Reaching movement was divided in two sub-phases, according to proximal postural control versus movement control demands, during which antagonist co-activation ratios were calculated for the muscle pairs LD/PM, PD/AD, TRIlat/BB and TRIlat/BR. Post-stroke's ipsilesional limb presented lower co-activation in muscles with an important role in postural control (LD/PM), comparing to the healthy subjects during the first sub-phase, when the movement was performed in the sagittal plane (p<0.05). Conversely, the post-stroke's contralesional limb showed in general an increased co-activation ratio in muscles related to movement control, comparing to the healthy subjects. Our findings demonstrate that, in post-stroke subjects, the reaching movement performed with the ipsilesional upper limb seems to show co-activation impairments in muscle pairs associated to postural control, whereas the contralesional upper limb seems to have signs of impairment of muscle pairs related to movement.
- Colon tumor CD31 expression is associated with higher disease-free survival in patients with metabolic syndromePublication . Silva, Ana; Pereira, Sofia S.; Brandão, José Ricardo; Brochado, Paulo; Monteiro, Mariana P.; Araújo, António; Faria, GilMetabolic syndrome (MS) is recognized as a risk factor for colon cancer (CC). However, how does the interplay between metabolic dysfunction caused by MS and its individual components affect CC microenvironment and prognosis remains unexplored. Angiogenesis and lymphangiogenesis are fundamental processes for tumor progression and dissemination, ensuring oxygen and nutrient delivery and supporting one of the most important pathways of tumor dissemination, contributing to metastasis. Thus, our aim was to evaluate whether the expression of molecular biomarkers involved in angiogenic and lymphangiogenic processes influenced CC clinicopathological features and prognosis in patients with MS. Clinical and pathological data of 300 patients submitted to CC surgical resection at a single tertiary hospital were retrospectively retrieved from hospital records. Tumor tissue microarrays of archived paraffin-embedded blocks were used to assess CD31, VEGF-A and D2–40 tissue expression by immunohistochemistry. The percentage of stained area was quantified by computerized morphometric analysis. No association between tissue expression of angiogenesis and lymphangiogenesis biomarkers and tumor clinical and pathological characteristics was found. However, in subgroup analysis of patients with MS, dysglycemia was associated with lower D2–40 expression (p = 0.007) and high waist-circumference was associated with higher D2–40 (p = 0.0029) and VEGF-A expression (p = 0.026). In an adjusted Cox proportional hazard model CD31 expression was significantly associated with greater disease-free survival (HR=0.62; 95% CI: 0.41–0.95, p = 0.028). No association was found between D2–40 and VEGF-A expression and CC prognosis. Our data reinforces previous reports that suggest the potential use of CD31 as a CC prognostic biomarker. Additionally, our data further supports the evidence for an interplay between metabolic dysfunction, tumor microenvironment, and vascularization pathways.
- Conjugados anticorpo-fármaco: uma nova perspetiva no tratamento oncológicoPublication . Barbosa, Crisália; Silva, Ana; Sousa, JoanaO tratamento oncológico reveste-se de múltiplas condicionantes, entre elas, os efeitos sistémicos e a resposta individual do doente, sendo, portanto, uma área terapêutica em constante investigação para encontrar esquemas terapêuticos que sejam menos lesivos e mais efetivos. No ano 2000, a Food and Drug Administration aprovou o primeiro medicamento conjugado anticorpo-fármaco (CAF). Os CAF pretendem combinar o direcionamento altamente específico de um anticorpo monoclonal e o poder potente de um fármaco ou toxina com atividade antineoplásica, objetivando a eliminação precisa e eficiente de células cancerígenas, melhorando a janela terapêutica. Embora os sucessos iniciais tenham ressaltadoo seu potencial, ainda não são amplamente utilizados nos diversos tipos de cancro. Identificar e caracterizar os CAF disponíveis em contexto nacional e internacional.Métodos:Em outubro de 2022, procedeu-se a uma pesquisa na base de dados Infomed do Infarmed (Autoridade Nacional do Medicamento e Produtos de Saúde, I.P.), da Food and Drug Administration, da Agência Europeia de Medicamentos e da Pharmaceuticals and Medical Devices Agency utilizando o sufixo “mab” para medicamentos autorizados. Foram eliminados da pesquisa os medicamentos que não se enquadravam no género CAF e percursores radiofarmacêuticos. Para a contextualização da temática, foi realizada uma pesquisa bibliográfica em artigos de revisão, revisão sistemática e meta-análises no motor de busca PubMed® com a palavra-chave “antibody-drug conjugate”, dos últimos 5 anos. Em outubro 2022, encontravam-se 13 medicamentos CAF autorizados pelas principais autoridades reguladoras. Em Portugal, foram encontrados 9 CAF com o estado de medicamento autorizado, sendo que 5 tinham indicação para tumores hematológicos e 4 para tumores sólidos. O potencial inovador dos CAF no tratamento oncológico tem encontrado diversas barreiras que condicionam a sua aprovação pelas diferentes autoridades reguladoras do medicamento, nacionais e internacionais. A eficácia destes complexos moleculares está dependente de vários fatores como: tamanho da molécula, eficácia do ligante, dependência do ciclo celular e variabilidade inter-individual, o que se tem traduzido numa grande variabilidade em termos de resultados observados, face ao expectável. Assim, as diferentes políticas de aprovação de medicamentos, em conjunto com o limitado balanço custo-efetividade tem condicionado a aprovação de novos CAF, com variação mundial, remetendo quase sempre a sua utilização para tumores refratários ou recidivantes. Apesar da expectativa inicial para o aumento do arsenal terapêutico em oncologia, existem diversas limitações associadas aos CAF que não se traduzem num valor terapêutico acrescentado, condicionando, por isso, a sua aprovação.
- Detection of AEDES ALBOPICTUS MOSQUITO in northern Portugal and study of the impact of its dispersalPublication . Silva, AnaAedes albopictus mosquito, known as the tiger mosquito, is an invasive mosquito originating from Asia, and its expansion across continents in both tropical and temperate zones, and the exponential growth of dengue cases in the last 50 years, poses a significant risk to human health. The aim of this study is to characterize the invasive species of the Aedes albopictus mosquito in the northern region of Portugal and raise awareness of its dispersal to other regions. The surveillance of Aedes albopictus mosquitoes in the Northern region is carried out through the collection of adult mosquitoes, using the BG trap and/or aspirator and collection of immature mosquitoes, using ovitraps and natural breeding sites. The reports for the Vector Surveillance Network between 2018 and 2022 were analyzed. The identification of Aedes albopictus mosquito first occurred in Portugal in September 2017 in the municipality of Penafiel, located in Northern Portugal, in a Retread company and has been established at this entry point since 2018. The presence of the mosquito in the North of Portugal represents a high risk of dispersion to other regions. This study is of great importance to the field of Public Health.
- Efeitos de um programa de reabilitação cardíaca fase manutenção no padrão alimentar e composição corporal em indivíduos com doença arterial coronáriaPublication . Vieira, Ágata; Sousa, Sara; Noites, Andreia; Silva, AnaA prática de exercício físico e a adoção de um padrão alimentar adequado num contexto de reabilitação cardíaca, parece influenciar a composição corporal e diminuir o risco de doenças cardiovasculares. O estudo teve como objetivo analisar os efeitos de um programa de reabilitação cardíaca em indivíduos com doença arterial coronária, no padrão alimentar e composição corporal. Estudo pré-experimental longitudinal, cuja amostra foi constituída por 7 indivíduos, inseridos na fase de manutenção da reabilitação cardíaca. Ocorreram dois momentos de avaliação, M0 e M1, com 16 semanas de diferença entre os mesmos durante as quais foi mantido um programa de Reabilitação Cardíaca. Foi utilizada a balança de bioimpedância Tanita InnerScan Model BC-543 TM para a mensuração do peso, percentagem de gordura total, massa magra e percentagem de água; a fita métrica para a medição da altura e perímetros e o adipómetro para a medição da gordura subcutânea. Através destes instrumentos, foi possível calcular o Índice de Massa Corporal, percentagem de gordura corporal, rácio cintura-anca e rácio cintura-altura. Caraterizou-se, ainda, o padrão alimentar de cada participante através do Questionário de Frequência Alimentar. A análise estatística foi feita através do software SPSS24, com nível de significância de 5%. Ao fim das 16 semanas de intervenção, verificou-se uma diminuição estatisticamente significativa na percentagem de gordura corporal (p=0,031) dos participantes. Nesta amostra, o programa de RC na fase de manutenção teve influência positiva sobre os valores da composição corporal.
- Effect of metabolic syndrome and individual components on colon cancer characteristics and prognosisPublication . Silva, Ana; Pereira, Sofia S.; Monteiro, Mariana P.; Araújo, António; Faria, GilMetabolic syndrome (MS) is recognized as a risk factor for colon cancer (CC). However, whether the cluster of metabolic changes that define MS also influence CC prognosis remains unclear. Thus, our aim was to investigate whether the presence of MS or any of the MS individual components could provide prognostic information on tumor phenotype and survival outcomes. Clinical and pathological data from patients with CC (n = 300) who underwent surgical resection at a single tertiary hospital were retrospectively collected to evaluate presence of MS components and diagnostic criteria, CC phenotype and disease outcomes. Patients were allocated into two groups according to the presence or absence of MS (n = 85 MS vs n = 83 non-MS). The overall prevalence of MS individual components was 82.7% for increased waist-circumference (WC), 61.3% for high blood pressure (BP), 48.8% for low HDL-cholesterol, 39.9% for high fasting glucose, and 33.9% for hypertriglyceridemia. Patients in the MS group presented smaller tumors (p = 0.006) with lower T-stage (p = 0.002). High BP (p = 0.029) and hypertriglyceridemia (p = 0.044) were associated with a smaller tumor size, while low-HDL (p = 0.008) was associated with lower T-stage. After propensity score matching using age, tumor size and staging as covariates high-BP (p = 0.020) and WC (p = 0.003) were found to influence disease-free survival, but not overall survival. In conclusion, despite MS being an established risk factor for CC, our data does not support the hypothesis that MS components have a negative impact on disease extension or prognosis. Nevertheless, a protective role of BP and lipid lowering drugs cannot be excluded.
- Estudo da adequabilidade de fracionamento dos comprimidos de amlodipina para obtenção da dose de 2,5 mgPublication . Barbosa, Crisália; Silva, Ana; Sousa, JoanaA dose anti-hipertensora oral de amlodipina recomendada em doentes pediátricos (6 -17 anos) é de 2,5 mg, uma vez por dia, como dose inicial. A obtenção da dose faz-se por fracionamento de comprimidos de 5 mg. Verificar a disponibilidade no mercado farmacêutico português de comprimidos de amlodipina de 5 mg adequados para fracionamento e obtenção da dose pediátrica recomendada (2,5 mg). Em setembro de 2023, procedeu-se a uma pesquisa na base de dados Infomed do Infarmed (Autoridade Nacional do Medicamento e Produtos de Saúde, I.P.). Foi criada uma base de dados no Microsoft Office Excel® com a totalidade de referências de amlodipina de 5 mg, com estado de medicamento autorizado e comercializado em Portugal. Foram obtidos e analisados os Resumo das Características do medicamento (RCM) e folhetos informativos (FI) dos medicamentos. A pesquisa revelou a existência de 22 referências de amlodipina de 5 mg com estado autorizado e comercializado em Portugal. Destas, apenas 59,1% (n=13) mencionam no RCM / FI a adequabilidade para fracionamento em 2 partes iguais. Das 9 referências que indicam não ser adequadas para obtenção da dose de 2,5 mg, pelo menos 66,7% (n=6) são ranhuradas. Apesar de vários comprimidos de amlodipina 5 mg apresentarem ranhura de fracionamento, o mesmo não significa que seja possível a obtenção da dose de 2,5 mg. O mercado português oferece uma boa diversidade de laboratórios que permite este ajuste de dose. Consultar a literatura do medicamento permite comprovar a adequabilidade de fracionamento e, portanto, é recomendada a todos os doentes, cuidadores e profissionais que necessitam de obter a dose 2,5 mg de amlodipina. Os clínicos devem ter presente esta informação quando prescrevem para o domicílio, uma vez que condiciona a liberdade de opção do laboratório do medicamento. Por sua vez, os profissionais de farmácia comunitária devem estar atentos a possíveis incoerências na prescrição que invalidem a correta obtenção da dose pediátrica.
- Impact of adiposity on staging and prognosis of colorectal cancerPublication . Silva, Ana; Faria, Gil; Araújo, António; Monteiro, Mariana P.Abdominal visceral fat is a well-recognized a risk for colorectal cancer (CRC). In contrast to the risk for CRC, the impact of adiposity in disease staging and patient survival is less well-established. Our aim was to critically review the literature on the influence of adiposity assessed by different methods routinely used in clinical settings, on CRC staging and prognosis. In the 32 studies reviewed, overweight was initially identified as a survival advantage, an evidence that was later challenged by studies suggesting that body adiposity is likely to have a deleterious effect in CRC outcomes, particularly in males. Hence, whether obesity has a negative impact in CRC staging or prognosis remains controversial. In sum, addressing the impact of body fat in CRC biological behavior is still an unmet need. Understanding how adiposity influences CRC staging and prognosis could allow further patient risk stratification for devising targeted interventions and improve clinical outcomes.
- Influence of environmental temperature and humidity on the acute ventilatory response to exercise in asthmatic adolescentsPublication . Silva, Ana; Duarte, José A.; Appell, Hans JoachimAsthma is a chronic inflammatory disorder of the respiratory airways affecting people of all ages, and constitutes a serious public health problem worldwide (6). Such a chronic inflammation is invariably associated with injury and repair of the bronchial epithelium known as remodelling (11). Inflammation, remodelling, and altered neural control of the airways are responsible for both recurrent exacerbations of asthma and increasingly permanent airflow obstruction (11, 29, 34). Excessive airway narrowing is caused by altered smooth muscle behaviour, in close interaction with swelling of the airway walls, parenchyma retractile forces, and enhanced intraluminal secretions (29, 38). All these functional and structural changes are associated with the characteristic symptoms of asthma – cough, chest tightness, and wheezing –and have a significant impact on patients’ daily lives, on their families and also on society (1, 24, 29). Recent epidemiological studies show an increase in the prevalence of asthma, mainly in industrial countries (12, 25, 37). The reasons for this increase may depend on host factors (e.g., genetic disposition) or on environmental factors like air pollution or contact with allergens (6, 22, 29). Physical exercise is probably the most common trigger for brief episodes of symptoms, and is assumed to induce airflow limitations in most asthmatic children and young adults (16, 24, 29, 33). Exercise-induced asthma (EIA) is defined as an intermittent narrowing of the airways, generally associated with respiratory symptoms (chest tightness, cough, wheezing and dyspnoea), occurring after 3 to 10 minutes of vigorous exercise with a maximal severity during 5 to 15 minutes after the end of the exercise (9, 14, 16, 24, 33). The definitive diagnosis of EIA is confirmed by the measurement of pre- and post-exercise expiratory flows documenting either a 15% fall in the forced expiratory volume in 1 second (FEV1), or a ≥15 to 20% fall in peak expiratory flow (PEF) (9, 24, 29). Some types of physical exercise have been associated with the occurrence of bronchial symptoms and asthma (5, 15, 17). For instance, demanding activities such as basketball or soccer could cause more severe attacks than less vigorous ones such as baseball or jogging (33). The mechanisms of exercise-induced airflow limitations seem to be related to changes in the respiratory mucosa induced by hyperventilation (9, 29). The heat loss from the airways during exercise, and possibly its post-exercise rewarming may contribute to the exercise-induced bronchoconstriction (EIB) (27). Additionally, the concomitant dehydration from the respiratory mucosa during exercise leads to an increased interstitial osmolarity, which may also contribute to bronchoconstriction (4, 36). So, the risk of EIB in asthmatically predisposed subjects seems to be higher with greater ventilation rates and the cooler and drier the inspired air is (23). The incidence of EIA in physically demanding coldweather sports like competitive figure skating and ice hockey has been found to occur in up to 30 to 35% of the participants (32). In contrast, swimming is often recommended to asthmatic individuals, because it improves the functionality of respiratory muscles and, moreover, it seems to have a concomitant beneficial effect on the prevalence of asthma exacerbations (14, 26), supporting the idea that the risk of EIB would be smaller in warm and humid environments. This topic, however, remains controversial since the chlorified water of swimming pools has been suspected as a potential trigger factor for some asthmatic patients (7, 8, 20, 21). In fact, the higher asthma incidence observed in industrialised countries has recently been linked to the exposition to chloride (7, 8, 30). Although clinical and epidemiological data suggest an influence of humidity and temperature of the inspired air on the bronchial response of asthmatic subjects during exercise, some of those studies did not accurately control the intensity of the exercise (2, 13), raising speculation of whether the experienced exercise overload was comparable for all subjects. Additionally, most of the studies did not include a control group (2, 10, 19, 39), which may lead to doubts about whether asthma per se has conditioned the observed results. Moreover, since the main targeted age group of these studies has been adults (10, 19, 39), any extrapolation to childhood/adolescence might be questionable regarding the different lung maturation. Considering the higher incidence of asthma in youngsters (30) and the fact that only the works of Amirav and coworkers (2, 3) have focused on this age group, a scarcity of scientific data can be identified. Additionally, since the main environmental trigger factors, i.e., temperature and humidity, were tested separately (10, 28, 39) it would be useful to analyse these two variables simultaneously because of their synergic effect on water and heat loss by the airways (31, 33). It also appears important to estimate the airway responsiveness to exercise within moderate environmental ranges of temperature and humidity, trying to avoid extreme temperatures and humidity conditions used by others (2, 3). So, the aim of this study was to analyse the influence of moderate changes in air temperature and humidity simultaneously on the acute ventilatory response to exercise in asthmatic children. To overcome the above referred to methodological limitations, we used a 15 minute progressive exercise trial on a cycle ergometer at 3 different workload intensities, and we collected data related to heart rate, respiratory quotient, minute ventilation and oxygen uptake in order to ensure that physiological exercise repercussions were the same in both environments. The tests were done in a “normal” climatic environment (in a gymnasium) and in a hot and humid environment (swimming pool); for the latter, direct chloride exposition was avoided.
- Intelligent wheelchair driving: a comparative study of cerebral palsy adults with distinct boccia experiencePublication . Faria, Brígida Mónica; Silva, Ana; Faias, Joaquim; Reis, Luís Paulo; Lau, NunoAn electronic wheelchair facilitates the autonomy and independence of a person, however specific cognitive, sensorial and perceptual skills are needed to conduct the assistive technology. These skills are also inherent to the sport boccia. Thus, the aim of this study is to understand the relationship between the experience of the participant in driving a wheelchair in relation to their autonomy and independence and also examine the practice of boccia in relation to the cognitive skills and performance in driving an intelligent wheelchair using a simulator. It was performed an evaluation of 28 participants, 6 of whom had no experience driving an electronic wheelchair and 22 had experience, 15 practice boccia and 13 did not practice this type of adapted sports. In the collection of data was tested three interfaces command of a smart wheelchair in a simulator. It was showed a good performance of the participants with experience in using electronic wheelchair and practitioners of boccia. It was also possible to observe that the autonomous and independent participants showed good results.