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Copyright © 2020 Elsevier B.V. All rights reserved., Background and aims: The role of inflammation in atherosclerosis development and expression in different arterial territories is unclear. Soluble CD40 ligand (sCD40L) mediates inflammation and atherogenesis. Through a systematic review and meta-analysis, we assessed whether sCD40L was dysregulated in stable atherosclerosis, irrespective of the diseased arterial territory, and whether this dysregulation differed according to the specific territory. Methods: Systematic literature searches were performed in MEDLINE, Cochrane Library, Web of Science, and Embase for studies reporting circulating sCD40L levels in individuals with and without stable atherosclerosis. sCD40L levels were compared using random-effects meta-analysis, weighted by the inverse variance method (study protocol: PROSPERO CRD42020181392). Results: Fifty-four studies (59 estimates) including 7705 patients and 7841 controls were analyzed. sCD40L levels were found to be increased in patients with atherosclerosis, irrespective of the territory (standardized mean difference [SMD] 0.43, 95% CI 0.29-0.57; 59 estimates; χ2 heterogeneity p < 0.001; I2 = 92%). SMD was greatest in carotid atherosclerosis (SMD 0.58, 95% CI 0.30-0.86; 17 estimates), followed by coronary (SMD 0.43, 95% CI 0.24-0.62; 33 estimates), lower extremity (SMD 0.26, 95% CI -0.02-0.54; 7 estimates), and renal atherosclerosis (SMD -0.07, 95% CI -2.77-2.64; 2 estimates) (χ2 heterogeneity p < 0.001; I2 ≥ 80% for all). Subgroup analysis revealed that sCD40L levels were increased in clinical, but not subclinical, atherosclerosis. Conclusions: sCD40L levels were increased in stable atherosclerosis, particularly in the carotid and coronary territories. These novel data support sCD40L as a marker of systemic atherosclerosis, possibly with differential roles in specific territories., TP acknowledges the support of Fundação para a Ciência e Tecnologia, Portugal (Project UID/BIO/04565/2020), and Programa Oper-acional Regional de Lisboa 2020 (Project N. 007317).

During the COVID-19 pandemic, Portugal has experienced three distinct SARS-CoV-2 infection waves. We previously documented the prevalence of SARS-CoV-2 immunity, measured by specific antibodies, in September 2020, six months after the initial moderate wave. Here we show the seroprevalence changes six months later, up to the second week of March 2021, shortly following the third wave, which was one of the most severe in the world, and two months following the start of the vaccination campaign. A longitudinal epidemiological study was conducted, with a stratified quota sample of the Portuguese population. Serological testing was performed, including ELISA determination of antibody class and titres. The proportion of seropositives, which was 2.2% in September 2020, rose sharply to 17.3% (95% CI: 15.8% – 18.8%) in March 2021. Importantly, circulating IgG and IgA antibody levels were very stable six months after the initial determination and up to a year after initial infection, indicating long-lasting natural immunity against SARS-CoV-2. Moreover, vaccinated people had higher IgG levels from 3 weeks post-vaccination when compared with previously infected people at the same times post-infection.

Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)., The mechanisms that regulate the systemic extent of atherosclerosis are not fully understood. We investigated whether the expression of circulating miRNAs is associated with the extent of stable atherosclerosis to a single territory or multiple territories (polyvascular) and with the severity of atherosclerosis in each territory. Ninety-four participants were prospectively recruited and divided into five age- and sex-matched groups: presenting no atherosclerosis, isolated coronary atherosclerosis, coronary and lower extremity atherosclerosis, coronary and carotid atherosclerosis, and atherosclerosis of the coronary, lower extremity, and carotid territories. The expression of six circulating miRNAs with distinct biological roles was assessed. The expression of miR-27b and miR-146 differed across groups (p < 0.05), showing a decrease in the presence of atherosclerosis, particularly in the three territories. miR-27b and miR-146 expression decreased in association with a higher severity of coronary, lower extremity, and carotid atherosclerosis. Polyvascular atherosclerosis involving the three territories was independently associated with a decreased miR-27b and miR-146 expression. Both miRNAs presented an area under the curve of ≥0.75 for predicting polyvascular atherosclerosis involving the three territories. To conclude, miR-27b and miR-146 were associated with the presence of severe polyvascular atherosclerosis and with the atherosclerosis severity in each territory. Both are potential biomarkers of severe systemic atherosclerosis.

Introduction Soluble CD40 ligand (sCD40L) activates different cell types involved in innate immunity, including macrophages and platelets. The influence of innate immunity, particularly of sCD40L pathway, on stable coronary artery disease (SCAD) expression is not fully understood. We evaluated if sCD40L expression is related to the presence of SCAD and to its clinical and anatomical severity. Methods We prospectively recruited two groups of age- and sex-matched participants: 1) without coronary artery disease (CAD) (calcium score=0, no soft plaques on coronary angioCT scan) (controls); and 2) with stable obstructive CAD (≥50% for the left main, ≥70% for other epicardial vessels, on invasive coronary angiography). Acute atherosclerotic events or coronary artery bypass grafting (CABG) within 12 months, previous percutaneous coronary intervention, heart failure, infection, malignancy and severe renal dysfunction were exclusion criteria. Clinical, laboratorial and anatomical data were prospectively collected. Serum was stored at −80°C and measurements were performed in a blinded fashion, by ELISA (sCD40L Human Quantikine). Results Sixty-three participants were included: 14 controls and 49 patients with SCAD. In SCAD patients, classical cardiovascular risk factors were globally more prevalent and the serum levels of sCD40L (5553±3356 vs 3099±644 ng/mL, p Conclusions Increased expression of sCD40L was associated with the presence of SCAD, with angina severity and with CAD severity, while previous revascularization was associated with decreased sCD40L levels. Funding Acknowledgement Type of funding source: None

Introduction The mechanisms underlying the different phenotypic presentations of atherosclerosis are still poorly understood. MicroRNAs regulate genetic expression at the post-transcriptional level and each has specific biological functions. MicroRNAs could therefore be useful for understanding the epigenetic drivers for development of isolated coronary atherosclerosis and more extensive disease (coronary and extra-coronary). We evaluated if the expression profile of circulating microRNAs was associated with coronary and multiterritorial atherosclerosis. Methods We prospectively recruited three groups of age- and sex-matched participants, with: 1) no coronary atherosclerosis (calcium score=0, no soft plaques in coronary angioCT scan), neither carotid or inferior limbs atherosclerosis (controls); 2) isolated obstructive coronary artery disease (CAD) (≥50% for the left main, ≥70% for other epicardial vessels) (isolated CAD group); 3) obstructive disease of the coronary, inferior limbs and carotid arterial beds (multi-territorial disease group). Obstructive atherosclerosis of carotid and inferior limbs arteries (≥50% stenosis by Doppler or angioCT imaging) was assessed in all participants. Acute atherosclerotic events or coronary revascularization within 12 months, heart failure, infections, malignancy and severe renal dysfunction were exclusion criteria. Six microRNAs with diverse mechanisms of action were selected (mir-21, miR-27b, miR-29a, miR-126, miR-146, miR-218) and measurements of their circulating levels were performed in a blinded fashion, using RT-PCR SYBR Green. Results Twenty four patients were included, including 8 patients in each group. Mean age was 61±9 years, and 83% were male. In patients with atherosclerosis, classical cardiovascular risk factors were globally more prevalent. The expression of miR-146 and miR-218, both of which regulate endothelial function, was significantly decreased in the isolated CAD group compared to controls (Figure; data are expressed as median [IQR]). There was a further decrease in the expression of both microRNAs in patients with multiterritorial atherosclerosis compared to patients with isolated CAD. The expression of other microRNAs did not differ. Smoking was associated with the presence of isolated CAD and multiterritorial atherosclerosis (14% vs 30% vs 56% of smokers across groups, p=0.002), and with a decreased expression of miR-218 (1.6 [0.02–83] fold vs 0.1 [0.001–0.7] fold, p=0.023). Conclusions The expression of the endothelial regulators miR-146 and miR-218 was decreased in patients with isolated CAD compared to controls, and even more hampered in patients with multiterritorial atherosclerosis. Higher degrees of endothelial dysfunction may therefore contribute to a more diffuse atherosclerotic presentation through miR-146 and miR-218. Atherogenesis related to smoking may be partially mediated by miR-218. Funding Acknowledgement Type of funding source: None

© 2016 – IOS Press and the authors. All rights reserved, AIMS: Oxidized low density lipoprotein (ox-LDL) has been reported as an inhibitor of nitric oxide (NO)-mediated dilatation in microcirculation. Oxidized LDL effect on NO metabolism of erythrocytes is not known. Therefore, this study aims to evaluate the effect of ox-LDL on erythrocytes NO metabolism. METHODS: The effect of different concentrations of human purified ox-LDL (25, 50 and 100 μg/mL) on NO metabolism was evaluated on blood of healthy subjects. RESULTS: An inhibitory effect of higher concentrations of ox-LDL on erythrocyte NO efflux levels was verified. Concentrations of NO efflux from erythrocytes were lower as consequence of treatments with 50 μg/mL ox-LDL treatment (1.6±0.27 nM) and 100 μg/mL ox-LDL treatment (1.3±0.22 nM) than control (1.9±0.28 nM). Opposite, ox-LDL incubation has a positive effect on GSNO content of erythrocytes. That effect is proportional to concentrations of ox-LDL treatments (10.8±1.4 nM for 25 μg/mL, 12.9±1.5 nM for 50 μg/mL and 12.1±1.9 nM for 100 μg/mL) and is significant relative to control (8.56±0.76 μM) and ACh (8.9±0.52 μM) aliquots. CONCLUSIONS: Presence of oxidized LDL in erythrocyte NO metabolism induces a decrease of NO efflux amount and an increase on intra-erythrocyte GSNO concentrations. These results suggest a role of ox-LDL in mobilization of NO between NO derivatives molecules in dependence of oxidized LDL concentration. An anti - reactive nitrogene role can be attributed to ox-LDL for its contribution in the erythrocyte scavenged ability for nitric oxide., Work was financially supported by Fundação para a Ciência e Tecnologia (SFRM/BPD/6308/2009).

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)., Background and Objectives: Tumor necrosis factor alpha (TNF-α) is proatherogenic and associated with the risk of acute ischemic events, although the mechanisms that regulate TNF-α expression in stable coronary artery disease (SCAD) are not fully understood. We investigated whether metabolic, inflammatory, and epigenetic (microRNA (miRNA)) markers are associated with TNF-α expression in SCAD. Materials and Methods: Patients with SCAD were prospectively recruited and their metabolic and inflammatory profiles were assessed. TNF-α levels were assessed using an enzyme-linked immunosorbent assay. The relative expression of six circulating miRNAs associated with the regulation of inflammation and/or atherosclerosis was determined. Results: Of the 24 included patients with the mean age of 65 (9) years, 88% were male, and 54% were diabetic. The TNF-α levels were (median (interquartile range)) 1.0 (0.7-1.1) pg/mL. The percentage of glycosylated hemoglobin (r = 0.418, p = 0.042), serum triglyceride levels (r = 0.429, p = 0.037), and C-reactive protein levels (r = 0.407, p = 0.048) were positively correlated with TNF-α levels. Of the candidate miRNAs, miR-146a expression levels were negatively correlated with TNF-α levels (as indicated by r = 0.500, p = 0.035 for correlation between delta cycle threshold (ΔCt) miR-146a and TNF-α levels). In multivariate analysis, serum triglyceride levels and miR-146a expression levels were independently associated with TNF-α levels. miR-146 expression levels were not associated with metabolic or other inflammatory parameters and were negatively correlated with the number of coronary vessels with obstructive disease (as indicated by r = 0.556, p = 0.017 for correlation between ΔCt miR-146a and number of diseased vessels). Conclusions: miR-146a expression levels were negatively correlated with TNF-α levels in patients with SCAD, irrespective of other metabolic or inflammatory markers, and with the severity of coronary artery disease. The results add to the knowledge on the role of miR-146a in TNF-α-based inflammation in SCAD and support future research on the potential therapeutic use of miR-146a in such a clinical scenario.

© 2015 – IOS Press and the authors. All rights reserved, Glutathione is an abundant molecule inside erythrocyte, originating S-nitrosoglutathione (GSNO) by reacting with nitric oxide (NO). GSNO has been regarded as a store and transporter of NO, with significant interest as a potential therapeutic agent, acting as an NO donor. NO metabolism inside the erythrocyte generates several derivatives, which can be altered by external and internal stimuli such as acetylcholine (ACh), a natural substrate of acetylcholinesterase (AChE). In spite of the knowledge gained in the last decades concerning NO efflux in erythrocytes little is known regarding erythrocyte GSNO efflux, which has also a significant role in microcirculation. Hence, the objective of this research was to evaluate the efflux of GSNO, concomitant with the efflux of NO, after stimulation with AChE effectors. To achieve these goals, the in vitro effect of AChE modulators – ACh and timolol – in erythrocyte NO and GSNO were studied. Timolol is an erythrocyte AChE inhibitor. Venous blood samples were collected from 18 healthy Caucasian men. For each blood sample, erythrocyte suspensions were obtained and incubated in the absence (controls) and presence of ACh and timolol maleate (10 _M final concentration of each modulator). Both timolol and Ach induced significant GSNO efflux in the erythrocyte when compared to the control; however the efflux was lower in the presence of timolol compared to ACh. Although erythrocyte NO efflux in presence of timolol is similar to the control, the efflux decreased when compared to the ACh treatment. The presence of timolol induces significant decrease of intra-erythrocyte GSNO levels, relative to control and ACh treatment. In conclusion, when erythrocytes were stimulated with ACh or timolol, GSNO efflux occurred associated with NO efflux. These new results bring new insight into the metabolism of erythrocyte NO and new possible therapeutic applications for GSNO., This study was supported by grants from the FCT - Fundação para a Ciência e a Tecnologia

Introduction: We examined the potential role of polymorphisms of the platelet genes GP1BA (rs2243093, rs6065 and VNTR), ITGB3 (rs5918), ITGA2 (rs938043469) and P2RY12 (rs2046934, rs6801273 and rs6798347) as risk factors for myocardial infarction (MI). Methods: The study population was divided into three groups: controls (n=235), MI at age ≤45 years (MI ≤45, n=44), and MI at age >45 years (MI >45, n=78). The control group was further divided into two subgroups (control ≤45 and >45), and subgroups including only men were also considered for statistical analysis. Polymorphisms were detected by polymerase chain reaction and restriction fragment length polymorphism analysis. Results: Regarding non-genetic risk factors, the control group differed statistically from the MI ≤45 group (p45 group (p45 was compared with the control group, with a higher risk of MI in the TT genotype (OR 2.852; 95% CI: 1.092-7.451; p=0.032). In the GP1BA rs6065 polymorphism, a statistically significant difference was found between control ≤45 only men and MI ≤45 only men, with a higher risk in the CT genotype (OR 5.568; 95% CI: 1.421-21.822; p=0.016), despite the low numbers included. The other polymorphisms studied did not show any statistically significant correlations. Conclusion: There is a statistically significant association between the TT genotype of the ITGA2 rs938043469 polymorphism and increased risk for MI >45. Resumo: Introdução: Determinou-se o papel de polimorfismos dos genes de expressão plaquetária GP1BA (rs2243093, rs6065 e o VNTR p.Ser415_Thr428(0_4)), ITGB3 (rs5918), ITGA2 (rs938043469) e P2RY12 (rs2046934, rs6801273 e rs6798347) como fatores de risco para o enfarte agudo do miocárdio (EAM). Métodos: A amostra foi dividida em três grupos: Controlo (n=235), EAM ≤45 anos (n=44) e EAM >45 anos (n=78). O grupo Controlo foi ainda dividido em dois subgrupos (Controlo ≤45 e >45). Subgrupos incluindo somente homens também foram considerados para fins estatísticos. Os polimorfismos foram estudados através de PCR e RFLP. Resultados: Em relação aos fatores de risco não genéticos, o grupo Controlo diferia estatisticamente do grupo EAM ≤ 45 anos (p45 anos (p45 anos e Controlo, associando-se o genótipo TT a aumento de risco de EAM (OR 2,852; IC 95% de 1,092 a 7,451; p=0,032). No polimorfismo rs6065 do gene GP1BA foi encontrada uma diferença estatística quando comparados os grupos Controlo ≤ 45 só homens e EAM ≤ 45 só homens, associando-se o genótipo C/T a um maior risco de EAM (OR 5,568; IC 95% de 1,421 a 21,822; p=0,016), apesar do baixo n. Os outros polimorfismos não apresentaram correlação significativa. Conclusão: Existe uma associação estatística significativa entre o genótipo T/T do polimorfismo rs938043469 do gene ITGA2 e o risco de EAM >45. Keywords: Myocardial infarction and platelet polymorphisms, GPIb-V-IX, GPIa-IIa, GPIIb-IIIa: ADP P2Y12 receptor, Palavras-chave: Enfarte agudo do miocárdio e polimorfismos plaquetários, GP Ib-V-IX, GP Ia-IIa, GP IIb-IIIa, ADP P2Y12 receptor

© Annals of Translational Medicine. All rights reserved., Acute myocardial infarction (AMI) is a critical clinical presentation of coronary artery disease (CAD). As pointed out previously by us, major clinical research efforts have been dedicated to the identification of patients at higher risk and to the diagnosis of CAD and AMI. Although a great pool of information concerning systemic inflammation markers have been so far collected in different cardiovascular conditions, the evolution of AMI is not well depicted., Fundação para a Ciência e Tecnologia contracts: SFRM/BPD/6308/2009 and UID/BIO/04565/2013; Programa Operacional Regional de Lisboa POR2020: LISBOA-01-0145-FEDER-007317

Myocardial infarction (MI) is a high prevalence cardiovascular disease with a tendency to increase. Although MI therapy has increased its effectiveness, the loss of myocardial function in consequence of MI is still responsible for major subsequent complications as rhythm changes and heart failure. In human hearts, MI is characterized by cardiomyocyte death and fibrin deposition, which is later replaced by scar tissue. In opposition, zebrafish heart undergoes minimal scaring and cardiac tissue can undergo full functionally regeneration in 60 to 120 days. Therefore, this animal model has been used in cardiovascular research as a model for studying mechanisms of cardiac regeneration. The hearts of zebrafish is anatomically different from the human heart, though the electrocardiogram (ECG) pattern and the critical conduction pathways are comparable to the human's. The objective of our full project is the implementation of an ECG recording system with 3 orthogonal electrodes in 2 planes, in order to create a 4D recording of the zebrafish cardiac electrical activity. Here we present our preliminary work related to a non-invasive ECG monitoring with two electrodes.

© 2016 – IOS Press and the authors. All rights reserved, BACKGROUND: Glaucoma is an optic neuropathy associated with vascular dysregulation and increased intra-ocular pressure (IOP). Timolol is used as treatment for reducing IOP, by limiting aqueous humour production. Increased NOS expression as well as decreased levels of nitric oxide (NO) metabolites, and high activity of erythrocyte acetylcholinesterase (AChE) were observed in primary open angle glaucoma patients. OBJECTIVE: This ex vivo study aims to evaluate timolol effect in NO efflux and its derivatives in glaucoma patient’s erythrocytes. METHODS: Venous blood from 15 glaucoma patients was collected. Erythrocyte suspensions were incubated with the AChE modulators acetylcholine (ACh) and timolol at 10 M. Erythrocyte NO efflux and S-nitrosoglutathione (GSNO) concentration were measured. RESULTS: No significant differences were obtained in erythrocyte NO efflux and GSNO concentration in response to ACh or timolol when compared with the untreated erythrocytes of glaucoma patients. When comparing the same incubation conditions for erythrocyte suspensions between glaucoma patients and healthy subjects, those from glaucoma patients showed higher NO efflux in presence and absence of timolol, and higher values of GSNO in the presence of timolol. CONCLUSIONS: We demonstrated that erythrocytes from glaucoma patients have similar availability to release NO both in absence and presence of timolol, and have higher GSNO values in presence of timolol., This study was supported by grants from Fundação para a Ciência e Tecnologia.

BACKGROUND: Auto-immune responses are associated with oxidized LDL (ox-LDL) release, a key factor in plaque destabilization. Data on the relationship between ox-LDL and T lymphocytes in human populations remains scarce. T cells also react with other molecules from the lesion and/or damage the myocardium. OBJECTIVE: The objective of the present study was to examine the relationship between circulating T lymphocytes, ox-LDL, markers of myocardial necrosis (cTnT), myocardial dysfunction (N-terminal pro-brain natriuretic peptide – NT-proBNP) and inflammation (C-reactive protein – CRP) in the setting of acute myocardial infarction. METHODS: A longitudinal study of 55 patients with ST-elevation myocardial infarction (STEMI) were evaluated at three time points: admission, 2 and 40 days following admission, together with 30 patients with stable angina (SA) and 56 subjects without coronary artery disease serving as controls (CTR). RESULTS: STEMI patients had maximal ox-LDL values and minimal levels of CD3+ T lymphocytes at admission, which was normalized during the recovery period. The increasing trend of CD3+ T cells was positively associated with an ox-LDL decline over time. CRP and cTnT longitudinal variations were negatively associated with the CD3+ T-cell increasing trend. These associations were not found in SA patients or controls. CONCLUSIONS: The associations found between CD3+ T lymphocytes, ox-LDL and cTnT suggest a specificity of the immune response in AMI towards arterial and myocardial inflammation and remodelling. This work was supported by the Fundação para a Ciência e Tecnologia (SFRM/BPD/6308/2009 and PIC/IC/82734/2007); and by Liga dos Amigos do Hospital de Santa Marta. published

© 2016 – IOS Press and the authors. All rights reserved, AIM: Soluble CD40 ligand (sCD40L) has been considered as a marker of thrombosis and inflammation in several diseases, including sepsis. Recent studies challenge this view and point to a role of sCD40L in vascular and endothelial function. An indication of that association in sepsis has not been obtained so far. Therefore, herein we evaluated association between sCD40L and markers of hemorheology and inflammation on context of septic shock. METHODS: Time-changes of sCD40L levels over 72 hours of Intensive Care Unit (ICU) internment were assessed in 22 patients with septic shock and compared with 36 healthy volunteers. Association of sCD40L levels with erythrocyte deformability and aggregation (as markers of hemorheology), plasma concentrations of haemoglobin (Hb, as markers of endothelial function) and white blood cells (WBC) count (as marker of low-grade inflammation) were assessed in patients with septic shock. RESULTS: At ICU admission, sCD40L concentrations in patients with septic shock were lower (p = 0.024) than levels of healthy volunteers. However, sCD40L did not change over 72 hours of internment (F = 2.1, p = 0.137). Soluble CD40L levels in patients with septic shock at ICU admission correlate with concentrations of Hb (r = 0.61, p = 0.00) and WBC count (r = 0.63, p = 0.00), but not to erythrocyte deformability (r≥0.157, p≤0.235) and aggregation (r≥–0.109, p≤0.192). CONCLUSIONS: These results seem to highlight a possible association of sCD40L to endothelial function and inflammation in septic shock context., Work was financially supported by Fundação para a Ciência e Tecnologia (SFRM/BPD/6308/2009)

© 2016 Elsevier Inc. All rights reserved., Involvement of soluble CD40 ligand (sCD40L) in thrombosis and inflammation on the context of coronary artery disease is currently being revised. In that perspective, we had studied the association of sCD40L with markers of platelet activation and markers of endothelial and vascular function. On that cohort, a stratification of patients with acute myocardial infarction (AMI) 1 month after percutaneous coronary intervention (PCI) was observed based on concentrations of sCD40L. The study intended to identify the groups of AMI patients with different profiles of sCD40L concentrations and verify how medication, clinical evolution, biochemical data, and markers of regulation of endothelial function at genetic (endothelial nitric oxide synthase polymorphisms) and post-transcriptional levels (circulating microRNAs) affect sCD40L serum levels. Lower quartiles of sCD40L (,2.3 ng/mL) were associated with higher concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP), high frequency of G894T polymorphism, and altered expression of a set of microRNAs assumed to be involved in the regulation of endothelial and cardiac function and myocardium hypertrophy, relative to patients in sCD40L upper quartiles. A characteristic sCD40L variation pattern in STEMI patients was identified. Low levels of sCD40L 1 month after PCI distinguish STEMI patients with worse prognosis, a compromised cardiac healing, and a persistent endothelial dysfunction, as given by the association between sCD40L, NT-proBNP, G894T polymorphism, and specific profile of miRNA expression. These results suggest sCD40L could have a prognostic value in STEMI patients., The work was financially supported by Fundação para a Ciência e Tecnologia (SFRM/BPD/6308/2009 and UID/BIO/04565/2013) and Liga dos Amigos do Hospital de Santa Marta.

© 2016 – IOS Press and the authors. All rights reserved, INTRODUCTION: Acetylcholinesterase (AChE) is located on outer surface of erythrocyte membrane. Gender-related diferences in erythrocyte AChE enzyme activity had been verified in young adults. It is also known that binding of acetylcholine (ACh) withAChE on erythrocyte membrane initiates a signal transduction mechanism that stimulates nitric oxide (NO) efflux. AIMS: This ex vivo study was done to compare the amount of NO efflux obtained from erythrocytes of healthy donors in males and females. METHODS: We included 66 gender age-matched healthy donors (40–60 years old). We performed quantification of erythrocyte NO efflux from erythrocytes and of the membrane AChE enzyme activity. RESULTS: There are no significant differences in NO efflux from erythrocytes between men and women. Regarding AChE enzyme activity values, in this range of age, no differences between genders were obtained. However, the values of AChE enzyme activity in the third quartile of NO efflux values were significantly higher (p < 0.05) in women than in men. CONCLUSIONS: The efflux of NO from erythrocyte of healthy humans did not change with gender. For the same range of values of NO efflux from erythrocytes, in both gender, it was verified higher values of AChE enzyme activity in women., Work was financially supported by Fundação para a Ciência e Tecnologia (SFRM/BPD/6308/2009).

© IOS Press and the authors. All rights reserved, INTRODUCTION: Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease of the motor system. It has been hypothesised that red blood cells (RBCs) may be involved in the disease process by the release of damaging molecules. OBJECTIVE: The aim of this ex vivo study is to compare RBCs biochemical and hemorheological parameters between ALS patients and healthy donors to identify novel biomarkers of the ALS disease. METHODS: We included 82 ALS patients and 40 gender age-matched healthy donors. We performed quantification of erythrocyte aggregation and deformability, nitric oxide (NO) efflux from RBCs, acetylcholinesterase (AChE) enzyme activity and intraerythrocytic concentration of nitrite, nitrate and S-nitrosogluthatione (GSNO). RESULTS: Erythrocyte deformability and AChE activity were increased in patients with ALS in comparison to healthy donors. NO efflux from RBCs and concentration of intraerythrocytic nitrite were lower in ALS patients. In patients, we found that for higher NO range of values the respiratory function is worse and that for higher AChE range of values the RBCs nitrite content increase. CONCLUSION: The results of the present study indicate that NO efflux from RBCs and RBCs AChE should be further explored as potential biomarkers for ALS.

© 2015 Elsevier Inc. All rights reserved., Reported in vitro data implicated soluble CD40 ligand (sCD40L) in endothelial dysfunction and angiogenesis. However, whether sCD40L could exert that influence in endothelial dysfunction and angiogenesis after injury in acute myocardial infarction (AMI) patients remains unclear. In the present study, we evaluated the association of sCD40L with markers of platelet activation, endothelial, and vascular function during a recovery period early after AMI. To achieve this goal, the time changes of soluble, platelet-bound, and microparticle-bound CD40L levels over 1 month were assessed in AMI patients and correlated with endothelial nitric oxide synthase (eNOS) polymorphisms, vascular endothelial growth factor (VEGF) concentrations, and platelet expression of P-selectin (CD62P). The association of soluble form, platelet-bound, and microparticle-bound CD40L with CD62P expression on platelets, a marker of platelet activation, was also assessed to evaluate the role of CD40L in the thrombosis, whereas the association with eNOS and VEGF was to evaluate the role of CD40L in vascular dysfunction. This work shows for the first time that time changes of sCD40L over 1 month after myocardial infarct onset were associated with G894T eNOS polymorphism and with the VEGF concentrations, but not to the platelet CD62P expression. These results indicate that, in terms of AMI pathophysiology, the sCD40L cannot be consider just as being involved in thrombosis and inflammation but also as having a relevant role in vascular and endothelial dysfunction., The work was financially supported by Fundação para a Ciência e Tencnologia (SFRM/BPD/6308/2009) and by Liga dos Amigos do Hospital de Santa Marta.

© Springer Science+Business Media New York 2015, In the human erythrocyte, band 3 protein mediates nitric oxide (NO) translocation and its effects are strongly related to phosphorylated/dephosphorylated intracellular states. The metabolism of NO could change in the presence of acetylcholinesterase (AChE). Therefore, the present study was designed to assess the effect of conformational changes in AChE (via N-19 and C-16 antibodies) and enzymatic inhibition/activation of protein kinase C (PKC) in erythrocyte NO mobilization in vitro. Our results show that by inhibiting PKC with cheletrine, impaired erythrocyte NO efflux and s-nitrosoglutathione (GSNO) levels were verified, while PKC's activation by Phorbol 12-myristate 13-acetate had the opposite effect. Those results demonstrate the influence of 4.1R complex and band 3 protein level of phosphorylation on NO efflux and GSNO concentration mediated by PKC inhibition/activation. In addition, the present study shows evidence that conformational changes in AChE promoted by incubation with N-19 and C-16 antibodies alter the enzyme's functional connection to acetylcholine (ACh) (AChE-ACh complex) in an irreversible manner, resulting in impaired GSNO concentration and NO efflux from the erythrocyte. Novel insight into NO metabolism in the erythrocyte is brought with the presented findings allowing new possibilities of modulating NO delivery, possibly involving PKC and AChE conformational alterations in combination., This study was supported by Fundação para a Ciência e a Tecnologia Grants (SFRM/BPD/6308/2009).

Oxidation of lipids and proteins represents a causative event for atherogenesis, which can be opposed by antioxidant activity. Elements, such as, Fe, Cu, Zn and Se can be involved in both mechanisms. Thus, evaluation of blood elemental levels, easily detected by PIXE, and of redox parameters may be useful in assessing the risk of atherosclerosis. A group of stable patients suffering from atherosclerosis, was matched with a cohort of normo-tensive and -lipidemic volunteers. Although no major discrepancies were observed for trace elemental levels in blood, increased concentrations of K and Ca were found in atherosclerotic group. Patients presented enhance levels of antioxidant (α-tocopherol) and decreased of protein oxidation (protein carbonyls), while for the lipid oxidation marker (malondialdehyde) no variation was observed. This study contributes to a better understanding of atherosclerosis development and its relationship with blood elemental levels, and set basis for further clinical trials with pathological groups in acute phase.

The distribution of Fe in skin was assessed to monitor body Fe status in human hereditary hemochromatosis. The paper reports on data from nine patients with hemochromatosis that were studied along the therapeutic programme. Systemic evaluation of Fe metabolism was carried out by measuring with PIXE technique the Fe concentration in plasma and blood cells, and by determining with biochemical methods the indicators of Fe transport in serum (ferritin and transferrin). The Fe distribution and concentration in skin was assessed by nuclear microscopy and Fe deposits in liver estimated through nuclear magnetic resonance. Elevated Fe concentrations in skin were related to increased plasma Fe (p < 0.004), serum ferritin content (p < 0.01) and Fe deposits in liver (p < 0.004). The relationship of Fe deposits in organs and metabolism markers may help to better understand Fe pools mobilisation and to establish the quality of skin as a marker for the disease progression and therapy efficacy.

The elemental composition of mineral structures in marine organisms can provide useful information to reconstruct environmental histories of individuals and distinguish populations or stocks. In cephalopods, as Octopus vulgaris, morpho-physiological description of vestigial shells may contribute to a better understanding of the physiology, of the process involved in the increment growth and may eventually provide important and useful tools for the validation of age determination methods. Nuclear microprobe analysis was used to map chemical elements in O. vulgaris vestigial shell. The maps contain elemental and morphological information, and enabled especially through Cl and Ca distributions to classify bands of concentric rings. The levels of P, Ca and Sr decrease from central region to external rings, while those of S and Cl showed an inverse tendency. Enhanced concentrations of Fe, Cu and Zn were found in external rings, and no significant variations were detected in the K and Br contents. The results indicate that three regions can be established on the basis of the elemental contents distributions. Specially, the P and Ca variability can distinguish rings from central and external regions. The differential incorporation of elements in the vestigial shell observed may reflect environmental and physiological factors that are affecting the life cycle of this species.

We examined the longitudinal changes of VEGF levels after percutaneous coronary intervention for predicting major adverse cardiac events (MACE) in coronary artery disease (CAD) patients. VEGF was measured in 94 CAD patients’ serum before revascularization, 1-month and 1-year after. Independently of clinical presentation, patients had lower VEGF concentration than a cohort of healthy subjects (median, IQ: 15.9, 9.0–264 pg/mL versus 419, 212–758 pg/mL;P<0.001) at baseline. VEGF increased to 1-month (median, IQ: 276, 167–498 pg/mL;P<0.001) and remained steady to 1-year (median, IQ: 320, 173–497 pg/mL;P<0.001) approaching control levels. Drug eluting stent apposition and previous medication intake produced a less steep VEGF evolution after intervention (P<0.05). Baseline VEGF concentration

Behcet's disease (BD) is a rare chronic vasculitis of unclear etiology. It has been suggested that inflammatory response has an important role in BD pathophysiology. Herein, we aimed to study the interplay between inflammation, iron metabolism and endothelial function in BD and search for its putative association with disease activity. Twenty five patients clinically diagnosed with BD were selected and twenty four healthy age-sex matched individuals participated as controls. Results showed an increase of total number of circulating white blood cells and neutrophils, serum transferrin, total iron binding capacity, mieloperoxidase (MPO), ceruloplasmin (Cp), C reactive protein, β2 microglobulin and Cp surface expression in peripheral blood monocytes in BD patients comparatively to healthy individuals (p < 0,05). Of notice, the alterations observed were associated to disease activity status. No significant differences between the two groups were found in serum nitric oxide concentration. The results obtained suggest an important contribution from innate immunity in the pathogenesis of this disease. In particular, surface expression of leukocyte-derived Cp may constitute a new and relevant biomarker to understand BD etiology.

© 2013 Saldanha C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited., Changes of oxygen partial pressure in tissues are sensed by the erythrocytes that with the efflux or with the maintenance of nitric oxide that contains promote vasodilation or vasoconstriction. Binding of acetylcholine with the acetylcholinesterase of the erythrocyte membrane originates a signal transduction mechanism that involves both the Gi protein as well as band 3 protein what stimulates nitric oxide efflux. The bioavailability of nitric oxide in presence of velnacrine maleate an inhibitor of acetylcholinesterase is preserved what means that there are no changes in the nitric oxide efflux. Timolol maleate is an inhibitor of acetylcholinesterase. The aim of this study was to assess the role of the timolol maleate in the erythrocyte in respect to bioavailability on nitric oxide and compare it with effect resulting of the presence of acetylcholine. Venous blood samples were collected from the forearm vein of fifteen healthy Caucasian men after informed consent. Each blood sample was divided in three 1 mL samples, centrifuged, and suspensions of erythrocyte were performed in order to achieve 10 μM final concentration either of acetylcholine or of the timolol. Levels of nitric oxide efflux were evaluated by amperometric method. S-nitrosoglutathione, nitrites and nitrates were assessed with the Griess reaction using the spectrophotometric method. The nitric oxide efflux by the erythrocyte in presence of timolol is like to the control sample but significantly decreased it when compared to the sample with acetylcholine. The presence of timolol induces decrease in the erythrocyte levels of S-nitrosoglutathione significantly in relation with the control and with acetylcholine samples. In conclusion, in vitro, in erythrocyte the nitric oxide content is maintained by timolol maleate. It may be expected the same role for timolol in the ocular microcirculation when being applied as a therapeutic compound., This study was supported by grants from the FCT - Fundação para a Ciência e a Tecnologia

Coronary artery disease (CAD) is the world’s leading cause of illness and death. In 2005, approximately 7.6 million deaths were attributed to coronary artery disease, accounting for almost 13% of the total deaths (WHO, 2011). From a pathophysiological point of view the disease could be considered as a severe clinical manifestation of atherosclerosis (Mallat & Tedgui, 2001). The disruption of an atherosclerotic plaque with superimposed thrombosis had been identified as the main cause of acute coronary syndromes, including acute myocardial infarction (AMI), and sudden death (Gensini & Dilaghi, 2002; Shah, 2003). The initially silent progression of arterial plaque, prompted by classic risk factors (including hypertension, diabetes mellitus, dyslipidaemia, age, stress, physical inactivity, dietary habits and cigarette smoking), is followed by a phase of acute or chronic progression toward an increasing degree of stenosis that eventually causes thrombosis (Gensini & Dilaghi, 2002; Fuster et al., 2005). Plaque disruption and/or endothelial activation represent the main trigger event for AMI, through exposure of plaque thrombogenic components to platelets and to clotting components of flowing blood. In this phase, haemostasis related risk factors and platelet status play a crucial role. However, current research supports the view of atherosclerosis as an inflammatory process that initiates and promotes lesion development to the point of acute thrombotic complications and clinical events. Thus, the time has come to embrace inflammation as a common pathway for atherogenic risk factors and for providing new opportunities for therapeutic intervention (Libby, 2003). Acute myocardial infarction is a critical clinical presentation of coronary artery disease in many asymptomatic patients and often the event is fatal. Establishing the presence of coronary lesions either in asymptomatic patients or in symptomatic patients with acute or chronic chest pain can be a challenging task. Consequently, major clinical research efforts

The aim of the present study was to investigate variations in oxidized LDL (oxLDL) at the onset of acute myocardial infarction (AMI) and over the recovery period, exploring their relationship with coronary disease severity. A follow-up of 50 AMI patients was evaluated against 25 healthy volunteers (reference group). The AMI patients were evaluated at three time points: at admission before the administration of IIb/IIIa inhibitors and angioplasty, and two and 40 days after intervention. Plasma oxLDL concentrations were measured by ELISA. oxLDL was found to be significantly higher in AMI patients in the acute phase relative to reference levels, decreasing progressively over the recovery period. The results also demonstrated that oxLDL levels were decreased in patients with the left circumflex artery (LCX) as culprit vessel compared to the left anterior descending coronary (LAD) or right coronary artery (RCA). The results highlight a significant increase in oxLDL concentration related to coronary artery disease severity, as conditions such as LCX lesions are usually associated with a favorable prognosis, contrasting with LAD-associated conditions that can compromise large areas of myocardium. The results thus suggest that oxLDL may constitute a promising marker in assessment of AMI evolution.

Experimental research indicates that oxidative processes play a role in susceptibility to a large number of diseases. A better understanding of the parameters affecting redox balance could delay and even prevent such processes.The present study aims to investigate blood parameters associated with antioxidant systems in a Portuguese population for the first time, taking into consideration gender, age range, lipid profile and smoking habits as influencing factors.One hundred and eighty-three healthy Portuguese subjects of both genders were recruited from the metropolitan area of Lisbon. The group consisted of individuals aged from 20 to 70 years, who gave their informed consent before participating in the study. All subjects were screened to determine eligibility, which was based on a clinical report. Subjects were considered eligible if they had no acute or chronic illness and were not taking any drugs or dietary supplements that could compromise the values of the studied parameters. The subjects were then divided into different subgroups according to gender, age range, lipid profile and smoking habits.Whole blood glutathione peroxidase activity and serum albumin, transferrin and uric acid were determined using commercially available kits. Superoxide dismutase activity in erythrocytes and thiobarbituric acid reactive substances in serum were measured using methods published elsewhere.Glutathione peroxidase activity was not affected by any of the studied variables, but superoxide dismutase activity decreased with smoking. Albumin levels remained unchanged under all conditions. Hyperlipidemia was associated with higher lipid peroxidation as well as higher uric acid levels. Gender was the strongest predictor for transferrin, total iron binding capacity and uric acid variations. Finally, a multivariate statistical model clearly separated genders and lipid profile and genders and smoking.The present study suggests that hyperlipidemia and smoking should be considered important selection criteria in epidemiological studies focusing on oxidative stress and on the atherosclerotic process.

Inflammation is now considered a key component of atherosclerosis, from fatty streak formation to plaque rupture, subsequent thrombosis, and progressive mechanical and dynamic obstruction. Rupture of the arterial plaque's fibrous cap exposes tissue factors present in the necrotic core, triggering inflammatory signaling, cell adhesion, and the coagulation cascade that eventually leads to thrombus. Cytokines and adhesion molecules are key components of these events that contribute to the development of an atherosclerotic plaque. The cytokine TNF-alpha and intercellular adhesion molecule-1 (ICAM-1) are indicators of basal inflammation, while the soluble forms of adhesion molecules such as CD40L and P-selectin indicate the extent of platelet activation. This study reports on the follow-up of 17 patients with confirmed acute myocardial infarction (AMI group) undergoing angioplasty and a matched control group of 16 patients without coronary artery disease as verified by coronary angiography. Patients from the AMI group were assessed at the onset of the acute coronary syndrome, within 24 h, before the administration of glycoprotein IIb/IIIa inhibitors and coronary angioplasty, and during the recovery period, two and 40 days after intervention. For both groups, clinical characteristics were documented and serum concentrations of soluble CD40L, P-selectin, ICAM-1, TNF-alpha, and conventional biochemical indicators were analyzed. For AMI patients, these indicators were recorded at study entry and during follow-up. Concentrations of cytokines and adhesion molecules were measured using commercial immunoassay (ELISA) kits. Significant variations in sP-selectin were observed relative to the control group. Immediately after myocardial infarction, sP-selectin levels rose markedly, followed by a sharp decrease two days later. After 40 days of recovery, sP-selectin levels rose again, returning to the initial values. Variations in sCD40L levels were not significant relative to controls. However, sCD40L concentrations tended to fall until the second day after infarction, followed by a rise, and by the 40th day of recovery levels were slightly higher than controls. Unlike sCD40L and sP-selectin, consistently higher levels of TNF-alpha relative to controls were observed, which were only significant after 40 days of recovery. No significant variations were observed for ICAM-1 serum concentrations in the AMI group. The variations observed demonstrate the role of inflammatory markers in AMI progression and highlight the importance of systemic inflammation in disease evolution. The increased concentration of sP-selectin at infarction onset is evidence of thrombosis and platelet activation. Later, during the recovery period when hemodynamic variables are returning to stability in part due to medication, rises in circulating levels of sCD40L and cytokines such as TNF-alpha may reflect the role of these molecules in the recovery of endothelial and myocardial tissues.

Copyright © 2006 by Humana Press Inc. Artigo original publicado por Humana Press Inc. Actual Editora da Revista Biological Trace Element Research: Springer [A publicação original está disponível em www.springerlink.com]. Prospective studies have demonstrated that an imbalance between oxidative damage and antioxidative protection can play a role in the development and progression of atherosclerosis. Also, genotypes with the apolipoprotein E ζ4 allele have been associated with an increase risk for this pathology. Based on this knowledge, the aim of this study was to evaluate indicators of the redox balance, trace elements, and apolipoprotein E allelic profile in subjects from the Lisbon population with clinically stable atherosclerosis, at risk for atherosclerotic events, and in healthy subjects for comparison. The activities of superoxide dismutase in erythrocytes and glutathione peroxidase in whole blood, plasma total thiols, and serum ceruloplasmin were kept unchanged among the three groups. Serum α-tocopherol was increased in atherosclerotic patients. Total malondialdehyde in serum and protein carbonyls in plasma, which are indicators of lipid and protein oxidative damage, respectively, reached their highest values in risk subjects. The concentrations of potassium and calcium, in plasma and in blood cells, were slightly elevated in patients and might reflect an electrolytic imbalance. Regarding the apolipoprotein E polymorphism, atherosclerotic patients had an increased incidence of the high-risk genotypes for atherogenesis (ζ3/ζ4 and ζ4/ζ4). A multivariate model applied to the general population using most of the parameters clearly separated the three groups at study (i.e., the healthy group from the steady-state group of risk disease and from the atherosclerotic one). As shown by us, the usefulness of biochemical and complementary genetic markers is warranted for a better knowledge on atherosclerosis molecular basis. Fundação para a Ciência e a Tecnologia; Centro de Biologia Ambiental; Instituto de Investigação Científica Bento da Rocha Cabral; Instituto Nacional de Saúde Dr. Ricardo Jorge.

The concentrations of V, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, and Pb were measured in digestive gland (DG), branchial hearts (BH), gill (G), and muscle (M) of Octopus vulgaris Cuvier, 1797 caught in three fishing areas of the Portuguese coast, Viana do Castelo, Cascais, and Santa Luzia, for 2 years. The elemental concentrations measured for the different tissues were in accordance with values reported in the literature. The digestive gland presented high concentration levels of Fe, Cu, and Zn, while the branchial hearts showed elevated levels of V, Ni, Mo, as well as Fe and Cu. Significant variations in As, V, Cu, Mo, and Pb tissue concentrations were observed for animals originated from different sampling sites. Pb and As determined in the digestive gland and branchial hearts of animals from Cascais and Santa Luzia, can reflect local environmental characteristics. The variability observed in the elemental concentrations may be useful to further assess the species susceptibility to environmental conditions.

During the COVID‐19 pandemic, Portugal has experienced three distinct SARS‐CoV‐2 infection waves. We previously documented the prevalence of SARS‐CoV‐2 immunity, measured by specific antibodies, in September 2020, 6 months after the initial moderate wave. Here, we show the seroprevalence changes 6 months later, up to the second week of March 2021, shortly following the third wave, which was one of the most severe in the world, and 2 months following the start of the vaccination campaign. A longitudinal epidemiological study was conducted, with a stratified quota sample of the Portuguese population. Serological testing was performed, including ELISA determination of antibody class and titers. The proportion of seropositives, which was 2.2% in September 2020, rose sharply to 17.3% (95% CI: 15.8–18.8%) in March 2021. Importantly, circulating IgG and IgA antibody levels were very stable 6 months after the initial determination and up to a year after initial infection, indicating long‐lasting infection immunity against SARS‐CoV‐2. Moreover, vaccinated people had higher IgG levels from 3 weeks post‐vaccination when compared with previously infected people at the same time post‐infection., During the COVID‐19 pandemic, Portugal experienced three distinct SARS‐CoV‐2 infection waves. We determined the presence of antibodies after the first wave, September 2020 resulting in 2.2% seropositivity, and after the 2/3 wave in March 2021, including a contribution of the vaccination campaign, seroprevelance of 17.3%. Longitudional survey from individuals infected during the first wave indicated long‐lasting immunity, slowly waning, 1 year after infection.

El selenio (Se), el cobre (Cu) y el cinc (Zn) son oligoelementos esenciales para los mamíferos con funciones biológicas bien demostradas en los seres humanos (Neve y Palmieri, 2000; Viegas-Crespo y cols., 2000). Aparte de otras funciones metabólicas relevantes, desempeñan papeles importantes en la regulación del equilíbrio redox celular y ex-tracelular actuando junto con las defensas antioxidantes (Yu, 1994). Varios estudios epidemiológicos han demostrado que las concentraciones de oligoelementos esenciales dependende factores como la edad, el sexo y las situaciones fisiológicas y patológicas (Versieck y Cornelis, 1989). Además, la localización geográfica también parece ser un factor importante en la determinación de las 1as concentraciones sanguineas de oligoelementos, ya que puede relacionarse con las influencias de características geoquímicas, el aporte de alimentos y agua, las condiciones sociales y ambientales, el estilo de vida y otros factores (Robberecht y Deelstra, 1994; Viegas-Crespo y cols., 2000; Pavão y cols., en prensa). Varios estudios clínicos prospectivos han indicado que existe una relación entre las concentraciones de estos elementos y el perfil lipídico sérico (Salonen y cols., 1991; Crespo y cols., 1994; Pavão y cols., en prensa). Asimismo, se cree que la deficiencia de estos oligoelementos puede relacionarse con la aparición de enfermedades degenerativas asociadas a aterogenia y lesión vascular (Neve, 1996; Mahalingam y cols., 1997). Este estudio forma parte de un proyecto dirigido a analizar el equilíbrio oxidante/antioxidante en varias poblaciones portuguesas con diferentes perfiles socioculturales y hábitos alimentarias. En el presente trabajo se describe el estado de los oligoelementos (concentraciones séricas de Se, Cu y Zn) en los habitantes de seis comunidades de zonas urbanas, rurales y pescadoras localizadas en el continente (población de Lisboa) y en el Archipiélago de las Azores - isla de S. Miguel. Se comentan las diferencias en estos estados de oligoelementos entre las poblaciones y también se analiza su relación con el sexo, la edad y el perfil lipídico. (Introducción)

The present study represents the first elemental distribution and composition characterization of the vestigial shell in Octopus vulgaris Cuvier, 1797. Ten specimens of O. vulgaris were collected monthly between January and July 2002, on the central coast of Portugal. Using nuclear microscopy, Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE) techniques, it was found that along vestigial shell transversal sections, the elemental concentrations were differential. Most striking were those of P, Ca, S, and Cl. At the core of the vestigial shell, high concentration levels of Ca and P were determined, declining towards the periphery. Also, trace concentrations of elements such as Fe, Cu and Zn were found to be higher in the external rings than the inner regions. Future complementary studies of vestigial shell chemical composition, as well as histology studies, are necessary to gain better understanding of the vestigial shell microstructure. Se presenta la primera caracterización de la distribución elemental y de la composición de la concha vestigial del pulpo Octopus vulgaris Cuvier, 1797. Diez muestras de O. vulgaris fueron recogidas mensualmente, entre enero y julio del 2002, en la costa central de Portugal. Utilizando microscopía electrónica, técnicas de espectrometría Rutherford de refracción (RBS) y emisión de rayos X inducida por partículas (PIXE), se pudieron encontrar, a lo largo de las secciones transversales de la concha vestigial, diferencias en las concentraciones elementales, en particular en las de P, Ca, S, y Cl. En el núcleo de la concha vestigial, se pudieron determinar altas concentraciones de Ca y P, que se iban reduciendo hacia la periferia. Asimismo, se encontraron microelementos, como el Fe, Cu y el Zn, a concentraciones que eran mayores en los anillos externos que en las regiones internas. Para una mejor comprensión de la microestructura de la concha vestigial, es necesario llevar a cabo estudios complementarios a éste, y también estudios histológicos. Instituto Español de Oceanografía