Browsing by Author "Bárbara, Cristina"
Now showing 1 - 10 of 18
Results Per Page
Sort Options
- Effects of Positive Airway Pressure Therapy on Red Blood Cell Proteome from Patients with Obstructive Sleep ApneaPublication . Coelho- Valentim, Cristina; Vaz, Fátima; Bárbara, Cristina; Penque, DeborahIntroduction: Obstructive Sleep Apnea (OSA) syndrome, a common public health concern, is characterized by recurrent arousals from sleep and intermittent hypoxemia that can lead to metabolic and cardiovascular diseases. We recently demonstrated that OSA syndrome can cause alterations in the red blood cells (RBC) proteome that may be associated with OSA outcomes. Here we intend to investigate whether the positive airway pressure (PAP) treatment can revert/modulate these proteome alterations.
- Evening and morning alterations in Obstructive Sleep Apnea red blood cell proteomePublication . Feliciano, Amélia; Vaz, Fátima; Valentim-Coelho, Cristina; Torres, Vukosava M.; Silva, Rita; Prosinecki, Vesna; Alexandre, Bruno M.; Almeida, Andreia; Almeida-Marques, Catarina; Carvalho, Ana S.; Matthiesen, Rune; Malhotra, Atul; Pinto, Paula; Bárbara, Cristina; Penque, DeborahThis article presents proteomics data referenced in [1] Using proteomics-based evaluation of red blood cells (RBCs), we have identified differentially abundant proteins associated with Obstructive Sleep Apnea Syndrome (OSA). RBCs were collected from peripheral blood of patients with moderate/severe OSA or snoring at pre- (evening) and post-night (morning) polysomnography, so that proteome variations between these time points could be assessed. RBC cytoplasmic fraction depleted of hemoglobin, using Hemovoid(™) system, were analyzed by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), the 2D image software-based analyzed and relevant differentially abundant proteins identified by mass spectrometry (MS). MS identified 31 protein spots differentially abundant corresponding to 21 unique proteins possibly due to the existence of post-translational modification regulations. Functional analysis by bioinformatics tools indicated that most proteins are associated with catalytic, oxidoreductase, peroxidase, hydrolase, ATPase and anti-oxidant activity. At morning a larger numbers of differential proteins including response to chemical stimulus, oxidation reduction, regulation of catalytic activity and response to stress were observed in OSA. The data might support further research in OSA biomarker discovery and validation.
- Evening and morning peroxiredoxin-2 redox/oligomeric state changes in obstructive sleep apnea red blood cells: Correlation with polysomnographic and metabolic parametersPublication . Feliciano, Amélia; Vaz, Fátima; Torres, Vukosava M.; Valentim-Coelho, Cristina; Silva, Rita; Prosinecki, Vesna; Alexandre, Bruno M.; Carvalho, Ana S.; Matthiesen, Rune; Malhotra, Atul; Pinto, Paula; Bárbara, Cristina; Penque, DeborahWe have examined the effects of Obstructive Sleep Apnea (OSA) on red blood cell (RBC) proteome variation at evening/morning day time to uncover new insights into OSA-induced RBC dysfunction that may lead to OSA manifestations. Dysregulated proteins mainly fall in the group of catalytic enzymes, stress response and redox regulators such as peroxiredoxin 2 (PRDX2). Validation assays confirmed that at morning the monomeric/dimeric forms of PRDX2 were more overoxidized in OSA RBC compared to evening samples. Six month of positive airway pressure (PAP) treatment decreased this overoxidation and generated multimeric overoxidized forms associated with chaperone/transduction signaling activity of PRDX2. Morning levels of overoxidized PRDX2 correlated with polysomnographic (PSG)-arousal index and metabolic parameters whereas the evening level of disulfide-linked dimer (associated with peroxidase activity of PRDX2) correlated with PSG parameters. After treatment, morning overoxidized multimer of PRDX2 negatively correlated with fasting glucose and dopamine levels. Overall, these data point toward severe oxidative stress and altered antioxidant homeostasis in OSA RBC occurring mainly at morning time but with consequences till evening. The beneficial effect of PAP involves modulation of the redox/oligomeric state of PRDX2, whose mechanism and associated chaperone/transduction signaling functions deserves further investigation. RBC PRDX2 is a promising candidate biomarker for OSA severity and treatment monitoring, warranting further investigation and validation.
- Hematological evaluation in males with obstructive Sleep apnea before and after positive airway pressurePublication . Feliciano, Amelia; Linhas, R.; Marçõa, R.; Cysneiros, A.; Martinho, C.; Reis, R.P.; Penque, Deborah; Pinto, P.; Bárbara, CristinaObstructive sleep apnea syndrome (OSAS) is a systemic inflammatory disease associated with cardiovascular consequences. Red blood cell distribution width (RDW), mean platelet volume (MPV), and platelet distribution width (PDW) are recognized biomarkers of cardiovascular morbidity/mortality. Limited data is available on the association between these parameters and OSAS severity and the relationship with positive airway pressure therapy (PAP). In this prospective study of male OSAS patients we analyzed hematological data in order to evaluate their value in predicting OSAS severity, the relationship with sleep parameters, and their behavior under PAP. Seventy-three patients were included (mean age 46.5 years), of which 36 were mild (49.3%), 10 moderate (13.7%), and 27 severe (37%). The mean RDW increased significantly with OSAS severity and showed a positive correlation with respiratory disturbance index and hypoxemic burdens. Additionally, a group of 48 patients (mean age 47.2 years) were submitted to PAP. After six months, red blood cell count, hemoglobin, hematocrit, and platelet count showed a significant decrease (p < 0.0001; p < 0.0001; p = 0.001; p < 0.0001; respectively). Concerning OSAS severity, these parameters also significantly decreased in mild patients (p = 0.003; p = 0.043; p = 0.020; p = 0.014; respectively) but only hemoglobin, hematocrit, and platelet count decreased in severe cases (p < 0.0001; p = 0.008; p = 0.018; respectively). This study demonstrated an association between RDW values and OSAS severity. Moreover, red cell and platelet parameters changed significantly after PAP, supporting its cardiovascular protective effect. RDW may become a simple/inexpensive blood biomarker, making it useful in prioritizing OSAS patients waiting for polysomnography, and red cell and platelet parameters could be useful in PAP follow up.
- Measuring influenza vaccine effectiveness against pneumococcal pneumonia using the screening methodPublication . Rodrigues, Ana Paula; Kislaya, Irina; Machado, Ausenda; Gómez, Verónica; Bárbara, Cristina; Gonçalves, Paulo; Nunes, BaltazarThe aim of this study was to evaluate the feasibility of using the screening method to estimate the influenza vaccine effectiveness against Invasive Pneumococcal Disease (IPD) and Pneumococcal Pneumonia (PP) using hospital and monitoring data.
- Obstructive sleep apnea syndrome: how are we in Portugal?Publication . Rodrigues, Ana Paula; Pinto, Paula; Nunes, Baltazar; Bárbara, CristinaIntroduction: Obstructive sleep apnea (OSA) is a breathing disorder with serious socio-economic consequences, being currently considered a public health problem, with patients at increased risk of cardiovascular diseases and traffic accidents. Despite the high prevalence of OSA reported in the literature is unknown the magnitude of OSA in Portugal, in particular, the number of cases currently diagnosed. Objectives: 1 To estimate the prevalence of OSA in the population of sentinel general practitioners (GP); 2 To identify factors potentially associated with severe OSA; 3. Characterize the diagnosis and treatment of OSA. Methods: Cross-sectional observational study in which sentinel physicians were invited to participate, by reporting all cases with a diagnosis of OSA (ICPC2 P16) registered on their lists of users. The scientific protocol and questionnaires were sent to physicians who agreed to participate. Results: A sample of 29 sentinel GP participated, with a population under observation of 46.685 users. 311 patients were identified with OSA (76.2% male) with a mean age of 62.8 years. No statistically significant differences between genders were observed. In the population under observation, the prevalence of OSA was 0.67% (CI 95%), being higher in males (1.07%). In the population aged above 25 years, there was a higher prevalence of OSA in both genders (0.89%), emphasizing the differences between genders (1.47% in males and 0.39 in female). The highest prevalence was observed in the age group 65 to 74 years (2.35%), being higher in males (4.02%). Underwent sleep study 97.7% of patients, which 56.2% performed polysomnography, the latter has been largely carried out in public institutions (89.1%). The average waiting time in public institutions was 6.8 months (0-36 months), compared to 1 month in private institutions (0-9 months). According to the severity of OSA, almost half of the patients (48.4%) with information on the apnea hypopnea index or respiratory disturbance index had severe OSA. Obesity (74.2%), hypertension (75.9%) and diabetes mellitus (34.1%) were the most frequent co-morbidities in these patients, verifying that being male (OR: 2.6) and having obesity (OR = 4.0) was associated with an increased risk of having severe OSA for all ages. 89.6% of patients were being treated with nasal CPAP, of which 96.1% had severe OSA and 85.2% had mild-moderate OSA, with a statistically significant difference. Among patients on CPAP, 62.8% were followed in specialized sleep consultation, and only 26.7% of patients who were not under CPAP were being followed in sleep consultation. Conclusion: In this population, the prevalence of OSA was similar to that reported in the literature in older age groups. Male gender and obesity were associated with an increased risk of severe OSA in all ages.
- Obstructive Sleep Apnea: Epidemiology and Portuguese patients profilePublication . Rodrigues, Ana Paula; Pinto, Paula; Nunes, Baltazar; Bárbara, CristinaIntroduction: Obstructive Sleep Apnea (OSA) is characterized by recurrent episodes of apnea and hypopnea, secondary to collapse of the upper airways during sleep. OSA is frequently associated to cardiovascular complications. In Portugal, its magnitude is unknown. Methods: In 2014 a cross-sectional study was performed using the Portuguese General Practi- tioner (GP) Sentinel Network (Rede Médicos Sentinela). Participants GP reported all OSA cases diagnosed and registered in their lists of users on the 31 December 2013. Frequency of OSA has been estimated by sex and age. OSA patients were also characterized by method of diagnosis, treatment, and underlying conditions. Association between risk factors and severe OSA (odds ratio) was calculated using a logistic regression model adjusting confounding. Results: Prevalence of OSA on the population aged 25 years or more was 0.89% (95 CI: 0.80-1.00%); it was higher in males 1.47% (95 CI: 1.30-1.67%) and in those aged between 65 and 74 (2.35%). Most had severe OSA (48.4%). Hypertension (75.9%), obesity (74.2%) and diabetes mellitus (34.1%) were the most frequent comorbidities. Being a male (OR: 2.6; 95 CI: 1.2-5.8) and having obesity (OR: 4.0; 95 CI: 1.8-8.6) were associated with an increased risk of severe OSA. Conclusion: Found frequency of OSA was lower than other countries estimates, which may be explained by differences on case definition but can also suggest underdiagnosis of this condition as reported by other authors.
- Obstructive Sleep Apnea: New insights into antioxidant activity and cellular response to stressPublication . Vaz, Fátima; Feliciano, Amélia; Silva, Ana Rita; Coelho, Cristina; Torres, Vukosava Millic; Bozanic, Vesna; Malhotra, Atul; Pinto, Paula; Bárbara, Cristina; Penque, DeborahObstructive sleep apnea (OSA) is a sleep¬related breathing disorder characterized by recurrent episodes of apnea/and hypopnea during sleep with resultant intermittent hypoxia and sleep fragmentation, leading to cardiometabolic diseases. OSA affects 3.7% to 26% of adult population, but frequently is underdiagnosed. By 2DIGE-proteomics approach, we have investigated red blood cells (RBC) in OSA to uncover new insights into putative chronic stress-induced RBC dysfunction that lead to inflammation and metabolic syndrome associated with OSA. A number of proteins as potential candidate biomarkers for OSA, such as the cytosolic antioxidant regulators, catalase (CAT) and peroxiredoxin2 (PRX2) was identified, needing additional biochemical research validation.
- Overview of proteomics studies in obstructive sleep apneaPublication . Feliciano, Amélia; Torres, Vukosava M.; Vaz, Fatima; Carvalho, Ana Sofia; Matthiesen, Rune; Pinto, Paula; Malhotra, Atul; Bárbara, Cristina; Penque, DeborahObstructive sleep apnea (OSA) is an underdiagnosed common public health concern causing deleterious effects on metabolic and cardiovascular health. Although much has been learned regarding the pathophysiology and consequences of OSA in the past decades, the molecular mechanisms associated with such processes remain poorly defined. The advanced high-throughput proteomics-based technologies have become a fundamental approach for identifying novel disease mediators as potential diagnostic and therapeutic targets for many diseases, including OSA. Here, we briefly review OSA pathophysiology and the technological advances in proteomics and the first results of its application to address critical issues in the OSA field.
- Prevalência de síndrome de apneia obstrutiva do sono: um estudo da Rede Médicos-SentinelaPublication . Rodrigues, Ana Paula; Pinto, Paula; Nunes, Baltazar; Bárbara, CristinaEste estudo tem como objetivo estimar a prevalência de SAOS com diagnóstico conhecido na população sob observação da Rede Médicos-Sentinela (MS).