Browsing by Author "Amaral, M"
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- Antibodies against HDL Components in Ischaemic Stroke and Coronary Artery DiseasePublication . Batuca, J; Amaral, M; Favas, C; Justino, G; Papoila, A; Ames, P; Alves, JDQuantitative and qualitative defects of high-density lipoprotein (HDL) are important in atherogenesis. In this study, we investigated whether antibodies against HDL components had additional value to conventional cardiovascular risk factors for the diagnosis of ischaemic stroke (IS) and coronary artery disease (CAD). Cross-sectional study was conducted on 53 patients with IS, 51 with CAD and 55 healthy controls, and in vitro studies to validate findings of the clinical study. We determined serum immunoglobulin G (IgG) antibodies against HDL (aHDL), apolipoproteins (aApoA-I, aApoA-II and aApoC-I) and paraoxonase-1 (aPON1) as well as PON1 activity (PON1a), total antioxidant capacity and biomarkers of endothelial activation (serum nitric oxide metabolites, 3-nitrotyrosine, VCAM-1 and ICAM-1); in vitro assays tested the capacity of IgG aHDL purified from high titer patients to inhibit PON1a and to reverse protective effect of HDL on endothelial cells. IgG aHDL, aApoA-I and aPON1 were higher in IS and CAD than controls (p < 0.001), predicted negatively PON1a and positively VCAM-1 and ICAM-1. By adding IgG aHDL and aApoA-I to a traditional cardiovascular risk factors model for IS and by adding IgG aHDL in a similar model for CAD, we obtained better discrimination of IS and CAD from healthy controls. IgG aHDL purified from IS and CAD inhibited PON1a by 38% (p < 0.01) and abrogated the protective effect of HDL on VCAM-1 expression by 126% compared with non-specific human IgG (p < 0.001). IgG against HDL components interfere with the antioxidant and anti-inflammatory properties of HDL and may represent novel biomarkers for vascular disease that need to be investigated in prospective studies.
- Cisticercose do tecido molePublication . Mocanu, I; Paula, F; Amaral, M
- Crise de retenção esplénica major num adulto com drepanocitosePublication . Paula, F; Amaral, M; Oliveira, Alves; Alves, JDA crise de retenção esplénica é uma complicação, frequentemente, fatal da drepanocitose. É rara em adultos, pela elevada incidência de autoesplenectomia durante a infância. Heterozigóticos com traços de drepanocitose e de beta-talassémia têm fenótipos menos graves, podendo manter um baço funcional até à idade adulta. Descrevemos um caso de crise de retenção esplénica num homem de 19 anos, com concentração mínima de hemoglobina de 2,9g/dL, que resolveu após esplenectomia emergente. Os poucos casos descritos na literatura acarretam uma mortalidade elevada. Um diagnóstico rápido e actuação imediata são necessários para garantir a sobrevivência. É apresentada uma revisão da fisiopatologia e da abordagem terapêutica desta entidade.
- Extended Release-Niacin increases anti-ApoA-I antibodies that block the anti-oxidant effect of HDL-C: the EXPLORE clinical trial.Publication . Batuca, JR; Amaral, M; Favas, C; Paula, F; AMES, PR; Papoila, AL; Alves, JDExtended Release-Niacin (ERN) is the most effective agent for increasing high-density lipoprotein-cholesterol (HDL-C). Having previously identified anti-HDL antibodies, we investigated whether ERN affected the antioxidant capacity of HDL and whether ERN was associated with the production of antibodies against HDL (aHDL) and apolipoprotein A-I (aApoA-I). METHODS: Twenty-one patients older than 18 years, with HDL-C ≤ 40 mg/dL (men) or ≤ 50 mg/dL (women) were randomly assigned to receive daily ERN (n = 10) or placebo (n = 11) for two sequential 12-week periods, with 4 weeks of wash-out before cross-over. Primary outcome was change of paraoxonase-1 (PON1) activity and secondary outcomes were changes in aHDL and aApoA-I antibodies. Clinical Trial Unique Identifier: EudraCT 2006-006889-42. RESULTS: The effect of ERN on PON1 activity was non-significant (coefficient estimate 20.83U/L, 95% CI -9.88 to 51.53; p = 0.184). ERN was associated with an increase in HDL-C levels (coefficient estimate 5.21 mg/dL, 95% CI 1.16 to 9.25; p = 0.012) and its subclasses HDL2 (coefficient estimate 2.46 mg/dL, 95% CI 0.57 to 4.34; p = 0.011) and HDL3 (coefficient estimate 2.73 mg/dL, 95% CI 0.47 to 4.98; p = 0.018). ERN was significantly associated with the production of aApoA-I antibodies (coefficient estimate 0.25 µg/mL, 95% CI 0.09-0.40; p = 0.001). aApoA-I titres at baseline were correlated with decreased PON activity. CONCLUSIONS: The rise in HDL-C achieved with ERN was not matched by improved anti-oxidant capacity, eventually hampered by the emergence of aApoA-I antibodies. These results may explain why Niacin and other lipid lowering agents fail to reduce cardiovascular risk.
- Extended-release niacin increases anti-apolipoprotein A-I antibodies that block the antioxidant effect of high-density lipoprotein-cholesterol: the EXPLORE clinical trial.Publication . Batuca, J; Amaral, M; Favas, C; Paula, F; Ames, P; Papoila, A; Alves, JDExtended-release niacin (ERN) is the most effective agent for increasing high-density lipoprotein-cholesterol (HDL-C). Having previously identified anti-HDL antibodies, we investigated whether ERN affected the antioxidant capacity of HDL and whether ERN was associated with the production of antibodies against HDL (aHDL) and apolipoprotein A-I (aApoA-I). METHODS: Twenty-one patients older than 18 years, with HDL-C ≤40 mg dl-1 (men) or ≤50 mg dl-1 (women) were randomly assigned to receive daily ERN (n = 10) or placebo (n = 11) for two sequential 12-week periods, with 4 weeks of wash-out before cross-over. Primary outcome was change of paraoxonase-1 (PON1) activity and secondary outcomes were changes in aHDL and aApoA-I antibodies. Clinical Trial Unique Identifier: EudraCT 2006-006889-42. RESULTS: The effect of ERN on PON1 activity was nonsignificant (coefficient estimate 20.83 U l-1 , 95% confidence interval [CI] -9.88 to 51.53; P = 0.184). ERN was associated with an increase in HDL-C levels (coefficient estimate 5.21 mg dl-1 , 95% CI 1.16 to 9.25; P = 0.012) and its subclasses HDL2 (coefficient estimate 2.46 mg dl-1 , 95% CI 0.57 to 4.34; P = 0.011) and HDL3 (coefficient estimate 2.73 mg dl-1 , 95% CI 0.47 to 4.98; P = 0.018). ERN was significantly associated with the production of aApoA-I antibodies (coefficient estimate 0.25 μg ml-1 , 95% CI 0.09-0.40; P = 0.001). aApoA-I titres at baseline were correlated with decreased PON activity. CONCLUSIONS: The rise in HDL-C achieved with ERN was not matched by improved antioxidant capacity, eventually hampered by the emergence of aApoA-I antibodies. These results may explain why Niacin and other lipid lowering agents fail to reduce cardiovascular risk.
- Insuficiência hepato-renalPublication . Carvalho, C; Brito, T; Amaral, M; Alves, JD
- Litíase coraliformePublication . Mocanu, I; Amaral, M
- Magnesium – association with inflammation and renal disease in systemic lupus erythematosusPublication . Cunha, L; Marcelino, G; Amaral, M; Alves, JDIntroduction: Recent studies suggest that magnesium deficiency may play a role in inflammation. In diabetes and cardio-vascular diseases, conditions with a component of chronic inflammation, C–reactive protein levels are higher and associated with low serum magnesium. The objective of this study is to evaluate serum magnesium levels in patients with systemic lupus erythematosus and its potential association with inflammation and renal manifestations. Methods: All patients with systemic lupus erythematosus followed in a Systemic Immune Diseases Unit, from January 2012 until January 2014, were included in this cross sectional analysis. Patients with infection, neoplasia, liver failure and chronic kidney disease (stage > 3) were excluded. Clinical information and laboratory results (serum magnesium, C-reactive protein, erythrocyte sedimentation rate, serum creatinine and spot urine test) were collected. A multivariate analysis was performed to explore possible predictive factors for hypomagnesaemia. Results: One hundred and two patients were included (94.1% female, 21-86 years). 33.4% had hypertension, 8.8% had diabetes and 20.6% had hypomagnesaemia (< 1.8mg/dL). There were no significant differences between the inflammatory parameters of patients with hypomagnesaemia or normomagnesaemia. Serum magnesium was significantly lower with increasing comorbidities (p = 0.01). Leukocyturia was significantly higher in the hypomagnesaemia group (p = 0.03) and haematuria had a negative correlation with serum magnesium (-0.23, p < 0.05). Multivariate analysis showed that patients with hypertension and diabetes had higher risk of hypomagnesaemia: OR 42.29 (95% CI, 1.43-1249.31). Leukocyturia was also individually and independently associated with hypomagnesaemia: OR 8.37 (95% CI, 1.40-49.97). Conclusion: The presence of hypomagnesaemia in our patients with systemic lupus erythematosus was high. There was no association between the levels of serum magnesium and the inflammatory parameters. Increasing comorbidities and leukocyturia were independent predictors of lower serum magnesium. Finally, the association of leukocyturia and haematuria with lower serum magnesium may suggest a relationship with a higher disease activity.
- Manifestações oftalmológicas de doenças sistémicasPublication . Pina, S; Coutinho, I; Amaral, N; Bernardo, M; Melo, A; Paula, F; Batista, F; Amaral, M; Alves, JD
- Peripapillary Retinal Nerve Fiber Layer Thickness and Peripheral Microcirculation in Raynaud’s DiseasePublication . Pedrosa, C; Pina, S; Paula, F; Amaral, M; Vaz, FPurpose: Normal-tension glaucoma has been associated with systemic vascular diseases such as peripheral vasospasm. This study aims to evaluate the influence of peripheral vasospasm on the thickness of the retinal nerve fiber layer (RNFL) in Raynaud's disease (RD), and the correlation between global RNFL and peripheral microcirculation features in RD patients. Methods: Observational cross-sectional study of 18 patients (35 eyes) with a diagnosis of RD followed in our clinic, and 20 healthy controls (39 eyes). RNFL parameters were obtained using spectral domain optical coherence tomography (SD-OCT Spectralis®, Heidelberg). Global and sectorial peripapillary RNFL thickness were registered. Age, gender, refractive error, best-corrected visual acuity and intraocular pressure were determined, and slit-lamp biomicroscopy and fundus examination were performed. Nailfold videocapillaroscopy (NC) was performed in the RD group to characterize capillary morphology and blood flow. Mann-Whitney and Fisher's exact tests were used for statistical analysis. Statistical significance level was set at p<0.05 (two-sided). Results: There was no significant difference in the global RNFL between RD patients and the control group (p=0.35). The presence of avascular areas in NC was associated with a lower global RNFL thickness (p=0.026). Conclusion: The association between avascular areas in NC and the lower global RNFL thickness in RD patients suggests that systemic vasospasm severity may be related to optic nerve damage propensity. Therefore, its presence in NC may identify RD patients at risk for optic nerve head damage. A larger sample with a long-term study is needed to support the clinical and therapeutic implications of our findings.