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Dive into the research topics where José A. Silva is active.

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Featured researches published by José A. Silva.


Journal of Hypertension | 2011

Arterial stiffness predicts cardiovascular outcome in a low-to-moderate cardiovascular risk population: the EDIVA (Estudo de DIstensibilidade VAscular) project.

J. Maldonado; Telmo Pereira; Jorge Polónia; José A. Silva; João Morais; M. Marques

Background Pulse wave velocity (PWV) is a recognized marker of arterial stiffness, although little knowledge exists of their relationship to long-term cardiovascular risk in general populations. Methods and results A prospective, multicenter, observational study included 2200 Portuguese nationals (1290 men), aged between 18 and 91 years (mean 46.33 ± 13.76 years). They underwent clinical assessment and annual PWV measurement using a Complior device, and major adverse cardiovascular events (MACEs) – death, stroke, myocardial infarction, unstable angina, peripheral arterial disease, revascularization, or renal failure – were recorded. During a mean follow-up of 21.42 ± 10.76 months, there were 47 nonfatal MACEs (2.1% of the sample). PWV was significantly higher in individuals with events than in those without events (11.76 ± 2.13 vs. 10.01 ± 2.01 m/s, respectively, P < 0.001). The study population was divided into two groups by PWV, classified as normal (PWV < 95th percentile) or high (PWV >95th percentile), according to predefined criteria for normality. Cumulative event-free survival at 2 years was 99.3% in the normal PWV group and 95% in the high PWV group. The hazard ratio for MACE in the high PWV group was 9.901 [95% confidence interval (CI) 5.00–19.59, P < 0.001], and 4.832 (95% CI 2.35–9.94, P < 0.001) when adjusted for other risk factors. For absolute PWV, the adjusted hazard ratio (per 1 m/s change) was 1.316 (95% CI 1.13–1.53, P < 0.001). Conclusion The results of the initial analysis of this study highlight the clinical relevance of PWV as a cardiovascular risk marker and demonstrate that PWV measurement can make an important contribution to assessment of cardiovascular prognosis.


Carbohydrate Polymers | 2013

Chitosan-caffeic acid-genipin films presenting enhanced antioxidant activity and stability in acidic media.

Cláudia Nunes; Élia Maricato; Ângela Cunha; Alexandra Nunes; José A. Silva; Manuel A. Coimbra

The use of chitosan films has been limited due to their high degradability in aqueous acidic media. In order to produce chitosan films with high antioxidant activity and insoluble in acid solutions caffeic acid was grafted to chitosan by a radical mechanism using ammonium cerium (IV) nitrate (60 mM). Genipin was used as cross-linker. This methodology originated films with 80% higher antioxidant activity than the pristine film. Also, these films only lost 11% of their mass upon seven days immersion into an aqueous solution at pH 3.5 under stirring. The films surface wettability (contact angle 105°), mechanical properties (68 MPa of tensile strength and 4% of elongation at break), and thermal stability for temperatures lower than 300 °C were not significantly influenced by the covalent linkage of caffeic acid and genipin to chitosan. Due to their characteristics, mainly higher antioxidant activity and lower solubility, these are promising materials to be used as active films.


Green Chemistry | 2016

Chitosan–genipin film, a sustainable methodology for wine preservation

Cláudia Nunes; Élia Maricato; Ângela Cunha; M. Angélica M. Rocha; Sofia Santos; Paula Ferreira; Manuel António Coimbra Rodrigues da Silva; Ana Maria Rodrigues; Osvaldo Amado; Joana Coimbra; Diana Silva; André Moreira; Sónia Mendo; José A. Silva; Eduarda Pereira; Sílvia M. Rocha; Manuel A. Coimbra

A novel approach is described using chitosan–genipin films as a sustainable method for wine preservation. Films prepared from fungi and from shrimp by-products showed similar mechanical and chemical properties. In addition, shrimp derived films showed no IgE positive reaction against shellfish allergenic compounds. The chitosan–genipin films were used to produce white wines without the addition of sulphur dioxide as a preservative. These wines showed lower susceptibility to browning, with organoleptic characteristics comparable to those prepared using sulphur dioxide. It is shown that the formation of iron-tartrate–chitosan complexes promotes the decrease of iron and other metal availability, minimizing oxidation reactions, as well as inhibiting microbial growth. The overall volatile character of the wines was maintained. However, the presence of chitosan–genipin films promotes the occurrence of Maillard and Strecker reactions, producing volatile compounds with positive wine aroma scents. The use of chitosan–genipin films in winemaking is an innovative, green and environmentally friendly technology that could be easily implemented at an industrial scale with no additional costs.


Blood Pressure Monitoring | 2014

Ambulatory blood pressure monitoring profile in urban African black and European white untreated hypertensive patients matched for age and sex.

Jorge Polónia; Tavares Madede; José A. Silva; José Mesquita-Bastos; Albertino Damasceno

IntroductionThe aim of this study was to compare the 24-h ambulatory blood pressure (ABP) profile in never-treated black hypertensive patients living in Africa, Mozambique (20–80 years), versus never-treated white hypertensive patients living in Europe. Patients and methodsABP recordings of untreated black hypertensive patients and white hypertensive patients with 24-h ABP of 130/80 mmHg or more were retrospectively selected from two computerized database records of ABP and matched for age by decades, sex, and BMI. ResultsBlack hypertensive patients were n=548, 47±12 years, 52% women, BMI=28.0±8.2 kg/m2, 7% smokers, 7% diabetics; white hypertensive patients were n=604, 47±15 years, 52% women, BMI=27.4±5.1 kg/m2, 8.4% diabetics, and 18% smokers (P<0.02). Black hypertensive patients versus white hypertensive patients showed higher casual blood pressure (BP) 160/104±19/14 versus 149/97±18/12 mmHg, 24-h ABP 146/92±16/13 versus 139/85±11/10 mmHg, daytime ABP 150/95±16/13 versus 143/88±13/11 mmHg, night-time BP 139/84±17/13 versus 130/78±13/10 mmHg (all P<0.001) and lower night-time BP fall 8.3±6.9 versus 10.1±8.7% (P<0.02) and higher BP variability. Differences were still significant in all decades above 30 years of age and when calculations were carried out separately for both men and women. The average 24-h heart rate did not differ between groups. ConclusionOur data suggest that untreated black hypertensive patients systematically present higher clinic and ABP values and a lower night-time BP fall than untreated white hypertensive patients for all spectra of age distribution. This might be the reason for the worse cardiovascular prognosis described in black hypertensive patients compared with white hypertensive patients.


Blood Pressure | 2014

Aortic pulse wave velocity and HeartSCORE: Improving cardiovascular risk stratification. A sub-analysis of the EDIVA (Estudo de DIstensibilidade VAscular) project

Telmo Pereira; J. Maldonado; Jorge Polónia; José A. Silva; João Morais; T. Rodrigues; M. Marques

Abstract Background. HeartSCORE is a tool for assessing cardiovascular risk, basing its estimates on the relative weight of conventional cardiovascular risk factors. However, new markers of cardiovascular risk have been identified, such as aortic pulse wave velocity (PWV). The purpose of this study was to evaluate to what extent the incorporation of PWV in HeartSCORE increases its discriminative power of major cardiovascular events (MACE). Methods and results. This study is a sub-analysis of the EDIVA project, which is a prospective cohort, multicenter and observational study involving 2200 individuals of Portuguese nationality (1290 men and 910 women) aged between 18 and 91 years (mean 46.33 ± 13.76 years), with annual measurements of PWV (Complior). Only participants above 35 years old were included in the present re-analysis, resulting in a population of 1709 participants. All MACE – death, cerebrovascular accident, coronary accidents (coronary heart disease), peripheral arterial disease and renal failure – were recorded. During a mean follow-up period of 21.42 ± 10.76 months, there were 47 non-fatal MACE (2.1% of the sample). Cardiovascular risk was estimated in all patients based on the HeartSCORE risk factors. For the analysis, the refitted HeartSCORE and PWV were divided into three risk categories. The event-free survival at 2 years was 98.6%, 98.0% and 96.1%, respectively in the low-, intermediate- and high-risk categories of HeartSCORE (log-rank p < 0.001). The multi-adjusted hazard ratio (HR) per 1 − standard deviation (SD) of MACE was 1.86 (95% CI 1.37–2.53, p < 0.001) for PWV. The risk of MACE by tertiles of PWV and risk categories of the HeartSCORE increased linearly, and the risk was particularly more pronounced in the highest tertile of PWV for any category of the HeartSCORE, demonstrating an improvement in the prediction of cardiovascular risk. It was clearly depicted a high discriminative capacity of PWV even in groups of apparent intermediate cardiovascular risk. Measures of model fit, discrimination and calibration revealed an improvement in risk classification when PWV was added to the risk-factor model. The C statistics improved from 0.69 to 0.78 (adding PWV, p = 0.005). The net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were also determined, and indicated further evidence of improvements in discrimination of the outcome when including PWV in the risk-factor model (NRI = 0.265; IDI = 0.012). Conclusion. The results clearly illustrate the benefits of integrating PWV in the risk assessment strategies, as advocated by HeartSCORE, insofar as it contributes to a better discriminative capacity of global cardiovascular risk, particularly in individuals with low or moderate cardiovascular risk.


Carbohydrate Polymers | 2016

Influence of a cationic polysaccharide on starch functionality

Josiane Callegaro Raguzzoni; Ivonne Delgadillo; José A. Silva

Fundamental rheology, differential scanning calorimetry and infrared spectroscopy have been used to evaluate the effect of a cationic polysaccharide, chitosan, on the gelatinization, gel formation and retrogradation of maize starch samples, under acidic aqueous conditions. Moderate acidic conditions (0.1molL(-1) acetic acid) have shown a (slight) positive effect on starch gelatinization process and structure development. The presence of chitosan increased the DSC onset gelatinization temperature and also shifted the onset of the storage modulus increase to higher temperatures. Formation of the starch gel, mainly gelation of the leached-out amylose, is somehow hindered by the presence of the cationic polysaccharide and, therefore, the retrogradation of starch at very early stage can be delayed by addition of chitosan. However, long-term retrogradation was slightly increased. FTIR pectroscopy did not reveal any significant interaction between both polysaccharides what is in accordance with the observed rheological behavior. Small additions of chitosan to starch-rich systems may be a useful strategy to obtain new textures with novel phase transition behaviors.


Frontiers of Medicine in China | 2018

Common Evaluations of Disease Activity in Rheumatoid Arthritis Reach Discordant Classifications across Different Populations

Helena Canhão; Ana Rodrigues; Maria João Gregório; Sara S. Dias; José António Melo Gomes; Maria José Santos; Augusto Faustino; Costa Ja; Cornelia F Allaart; Emilia Gvozdenović; Désirée van der Heijde; Pedro M Machado; Jaime Branco; João Eurico Fonseca; José A. Silva

Objectives The classification of disease activity states in rheumatoid arthritis (RA) can be achieved through disease activity indices, such as the Disease Activity Score in 28 joints erythrocyte sedimentation rate (DAS28-ESR), the Simplified Disease Activity Index (SDAI), and the Clinical Disease Activity Index (CDAI). Subjective measurements, such as patient reported outcomes have been incorporated into several of these indices alongside more objective assessments, such as increases in the ESR and C-reactive protein. Moreover, while they use similar criteria, different indices weight these criteria to different extents. Therefore, the classifications based on each evaluation may not always be the same. We aim to compare the performance of the three indices and their individual components in two different populations. Methods Data from Dutch and Portuguese adherent centers were extracted from the METEOR database, a multinational collaboration on RA. We included a total of 24,605 visits from Dutch centers (from 5,870 patients) and 20,120 visits from Portuguese centers (from 3,185 patients). We compared the disease activity states as evaluated by the DAS28-ESR, CDAI, and SDAI across the two populations. In addition, we analyzed the individual components of each evaluation, including their respective contributions to the outcome, in each population. Results We found significant differences in the disease activity states classified with the DAS28-ESR between the two populations. SDAI and CDAI had more congruous results. While the proportion of visits to Dutch and Portuguese centers that were classified as “in remission” was very similar between the CDAI and SDAI, the DAS28-ESR gave discordant results. Dutch patients had lower ESRs, which is more heavily weighted in the DAS28-ESR. In addition, even though the mean physicians’ global assessment values did not vary significantly for Dutch vs Portuguese physicians, we found that doctors at Portuguese centers overall scored the physician’s global assessment lower than Dutch physicians for patient visits classified by disease activity state. Conclusion While the CDAI and SDAI assigned disease activity states that were largely similar, the DAS28-ESR was often discordant across the two populations. Moreover, we found that physicians, more than patients, evaluated disease activity differently among the Portuguese and Dutch populations.


Blood Pressure Monitoring | 2017

Association between ambulatory blood pressure values and central aortic pressure in a large population of normotensive and hypertensive patients

Ana Rouxinol-Dias; Sara Araújo; José A. Silva; Loide Barbosa; Jorge Polónia

Objective Our aim was to examine the association of ambulatory blood pressure monitoring (ABPM) and central blood pressure (CBP) data in a large set of normotensive and hypertensive patients and its relation with pulse wave velocity (PWV). Patients and methods This cross-sectional study was carried out in a single centre and included 2864 individuals who carried out an ABPM, measurement of CBP from the aortic waveform (SphygmoCor) and carotid-femoral PWV (Complior). Results In our study, 26.6% of the normotensive individuals and 32.5% of controlled hypertensive patients had abnormal values of at least one or of both ABPM and CBP values, compared with 96.6% of uncontrolled hypertensive patients. In the overall population, normal ABPM and CBP occurred in 25.3% (group 1), abnormal ABPM and CBP occurred in 44.4% (group 4), abnormal ABPM and normal CBP occurred in 10.5% (group 3) and normal ABPM and abnormal CBP occurred in 19.8% (group 2). PWV was significantly superior in group 4 versus group 3; group 4 versus group 1 and group 3 versus group 2 and group 2 versus group 1 (Mann–Whitney U-test; P<0.001). Conclusion At least 26–32% of patients classified as normotensive or controlled hypertensive patients have abnormal ABPM or CBP associated with target organ damages. When abnormal values of ABPM and CBP coexist, target organ damage (aortic stiffness) is greater than that occurring when only one abnormal ABPM or CBP is present in the absence of the other. Isolated central hypertension entails greater organ damage than both normal ABPM and CBP. These patients may be at higher risk of further target organ damage because of unawareness of their central hypertension.


Blood Pressure Monitoring | 2016

High salt intake is associated with a higher risk of cardiovascular events: a 7.2-year evaluation of a cohort of hypertensive patients.

Jorge Polónia; José Paulo Monteiro; Joana R. Almeida; José A. Silva; Susana Bertoquini

BackgroundIt is controversial whether high salt intake is directly associated with cardiovascular (CV) events and how far this relation is independent of blood pressure (BP). As Portugal has higher salt consumption and higher mortality by stroke than other European countries, we examined whether salt intake could predict the development of stroke and CV events in a hypertensive population. MethodsIn a longitudinal retrospective study of a cohort of 608 adult treated hypertensive patients 54.1±14.3 years of age, BMI 29.3±8.3 kg/m2, 56.3% women and 17.1% diabetics, we evaluate the long-term prognostic significance of urinary sodium (UNa) excretion measured in 24 h valid samples within the first 3 months after admission along with 24 h ambulatory blood pressure monitoring and pulse wave velocity [(PWV), complior)] measurements. ResultsThe mean follow-up duration was 7.2 years (0.5–11.1 years), during which 122 CV events occurred including 80 strokes and 36 coronary events. In 608 patients (group A=507 without events and group B=101 with events: 69 strokes, 26 coronary events, six others), the mean 24 h UNa was 208±79 mmol/day, corresponding to a salt intake of 12.1±4.6 g/day. Twenty-four hours UNa correlated positively with BMI, PWV and systolic blood pressure (SBP) particularly with night-time SBP. Group B versus A showed higher UNa (260+98 vs. 198+71 mmol/day, P<0.001) and higher PWV, BP office, 24 h, daytime and night-time SBP. Logistic regression analysis identified age, night-time SBP and 24 h UNa+ [HR=1.09 (95% CI, 1.06–1.12, P<0.001)] for each 10 mmol increase of UNa+ as the only independent predictors of CV events. UNa+ above the median (189 mmol sodium/day) predicted CV events with HR=2.99 (95% CI, 1.75–5.13, P<0.001) with worse CV event-free survival rates (log rank statistics of 17.44, P<0.001). ConclusionIn a cohort of hypertensive patients, high salt intake independently predicts the occurrence of CV events, particularly of stroke.


Vascular Health and Risk Management | 2017

Annual deterioration of renal function in hypertensive patients with and without diabetes

Jorge Polónia; André Azevedo; Miguel Monte; José A. Silva; Susana Bertoquini

Background Chronic kidney disease (CKD) complicates hypertension and diabetes. Knowledge of the deterioration rate of CKD may anticipate adjustment of therapies with renal elimination. This study evaluates the rate of annual deterioration of renal function in hypertensive patients either with type 2 diabetes (DM2) or without it (non-DM) followed for 5 years and relates it with blood pressure (BP) and glycemic control. Materials and methods Out of a total of 1924 patients, 1023 patients (594 non-DM and 429 DM2, 53% female, aged 62.1±10.2 years) were evaluated over 5 years for the annual evolution of renal function (estimated glomerular filtration rate [eGFR], Modification of Diet in Renal Disease) ambulatory 24-hour blood pressure and metabolic parameters, corresponding to the analysis of 2378 patient-years. Results DM2 and non-DM did not differ for age, mean 24-hour BP levels, nighttime BP, albuminuria, and body mass index. DM2 versus non-DM showed a higher (p<0.02) prevalence of stage 3 CKD (24.0% vs 18.0%, eGFR 30–59), stage 4 (5.4% vs 2.7%, eGFR 15–29), and stage 5 (0.8% vs 0.5%, eGFR <15). Average annual decline of eGFR was 3.3±8.2 in DM2 versus 2.4±7.7 in non-DM (p=0.12, nonsignificant). Annual changes of eGFR and of albuminuria correlated (r=0.578, p<0.001). In multivariate analysis, age, nighttime BP, double inhibition of renin angiotensin system, albuminuria, and HbA1c >8.0% in DM2 predicted the decline in eGFR. On average, 16.2% of DM2 and 13.1% of non-DM moved each year toward a more severe stage of CKD. For initial eGFR <90 mL/min/1.73 m2, 26.4% of DM2 and 18.1% of non-DM patients showed a reduction per year >10% from the previous eGFR value (p=0.042). Conclusion Progressive deterioration of renal function each year is frequent in hypertensive diabetic and non-diabetic patients. Beyond aging, this is particularly dependent on BP control particularly at nighttime, on drug therapy, and on highly abnormal glucose control.

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Susana Bertoquini

Fernando Pessoa University

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J. Maldonado

Fernando Pessoa University

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Loide Barbosa

Universidade Federal de Minas Gerais

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Telmo Pereira

Instituto Politécnico Nacional

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