Metabolomics and lipidomics reveal the effects of the toxic dinoflagellate Alexandrium catenella on immune cells of the blue mussel, Mytilus edulis.

The increasing occurrence of harmful algal blooms, mostly of the dinoflagellate Alexandrium catenella in Canada, profoundly disrupts mussel aquaculture. These filter-feeding shellfish feed on A. catenella and accumulate paralytic shellfish toxins, such as saxitoxin, in tissues, making them unsafe for human consumption. Algal toxins also have detrimental effects upon several physiological functions in mussels, but particularly on the activity of hemocytes - the mussel immune cells. The objective of this work was to determine the effects of experimental exposure to A. catenella upon hemocyte metabolism and activity in the blue mussel, Mytilus edulis. To do so, mussels were exposed to cultures of the toxic dinoflagellate A. catenella for 120 h. The resulting mussel saxitoxin load had measurable effects upon survival of hemocytes and induced a stress response measured as increased ROS production. The neutral lipid fraction of mussel hemocytes decreased two-fold, suggesting a differential use of lipids. Metabolomic 1H nuclear magnetic resonance (NMR) analysis showed that A. catenella modified the energy metabolism of hemocytes as well as hemocyte osmolyte composition. The modified energy metabolism was reenforced by contrasting plasma metabolomes between control and exposed mussels, suggesting that the blue mussel may reduce feed assimilation when exposed to A. catenella.

Usefulness of maximal oxygen pulse in timing of pulmonary valve replacement in patients with isolated pulmonary regurgitation.

Patients with pulmonary regurgitation after tetralogy of Fallot repair have impaired aerobic capacity; one of the reasons is the decreasing global ventricular performance at exercise, reflected by decreasing peak oxygen pulse. The aims of our study were to evaluate the impact of pulmonary valve replacement on peak oxygen pulse in a population with pure pulmonary regurgitation and with different degrees of right ventricular dilatation and to determine the predictors of peak oxygen pulse after pulmonary valve replacement. The mean and median age at pulmonary valve replacement was 27 years. Mean pre-procedural right ventricular end-diastolic volume was 182 ml/m2. Out of 24 patients, 15 had abnormal peak oxygen pulse before pulmonary valve replacement. We did not observe a significant increase in peak oxygen pulse after pulmonary valve replacement (p=0.76). Among cardiopulmonary test/MRI/historical pre-procedural parameters, peak oxygen pulse appeared to be the best predictor of peak oxygen pulse after pulmonary valve replacement (positive and negative predictive values, respectively, 0.94 and 1). After pulmonary valve replacement, peak oxygen pulse was well correlated with left ventricular stroke and end-diastolic volumes (r=0.67 and 0.68, respectively). Our study confirms the absence of an effect of pulmonary valve replacement on peak oxygen pulse whatever the initial right ventricular volume, reflecting possible irreversible right and/or left ventricle lesions. Pre-procedural peak oxygen pulse seemed to well predict post-procedural peak oxygen pulse. These results encourage discussions on pulmonary valve replacement in patients showing any decrease in peak oxygen pulse during their follow-up.

Predictors of long-term use of evidence-based therapies after non-ST-segment elevation acute coronary syndrome. The S-Témoin survey.

BACKGROUND: We evaluated correlates of prolonged use of evidence-based therapies in patients discharged after non-ST-segment elevation acute coronary syndrome (NSTE ACS). METHODS: 598 cardiologists enrolled 2443 patients at outpatient clinics 2-12 months after discharge for NSTE ACS. The use of cardiac medications for secondary prevention (antiplatelets, beta-blockers, angiotensin-converting enzymes, and statins) was evaluated. RESULTS: A total of 2386 (97.7%) patients were on either antiplatelet monotherapy (n=623, 26.1%) or combination therapy (n=1763, 73.9%) at follow-up. Combination antiplatelet therapy declined by 23 percentage points (82.3% to 59.4%) 9-12 months after discharge, whereas use of other cardiac medications remained constant or increased. After multivariable analysis, the strongest predictors of combination antiplatelet therapy were PCI with a stent (odds ratio [OR] 3.75, 95% confidence interval [CI] 2.12-6.67), drug-eluting stents (OR 3.25, 95% CI 1.73-6.08), late PCI (OR 3.21, 95% CI 2.12-4.87) and statins at discharge (OR 1.98, 95% CI 1.40-2.80). Among the independent predictors of beta-blocker and statin use were extent of coronary artery disease and cardiac medications prescribed at discharge. CONCLUSIONS: After NSTE ACS, implementation of recommendations on long-term use of evidence-based therapies depends largely on in-hospital management. A variety of clinical characteristics are also predictive of long-term use.

An unusual combination of possible causes of sudden death imaged by 64-slice computed tomography.

Hypertrophic cardiomyopathy and anomalous origin of the coronary arteries are important causes of sudden cardiac death in the young, for which several diagnostic imaging modalities are currently available. We report the case of a young sudden cardiac death survivor in whom the unusual coexistence of hypertrophic cardiomyopathy and anomalous origin of the left circumflex artery was demonstrated using 64-slice computed tomography.

Dose-related efficacy of irbesartan in patients, with mild-to-moderate essential hypertension.

OBJECTIVE: A prospective open multicentre study was conducted in patients with mild-to-moderate hypertension to compare the efficacy on diastolic blood pressure (DBP) and tolerance of treatment with either irbesartan 150mg od (once daily) or irbesartan 300mg od in patients who were defined as non-normalised responders with irbesartan 150mg od. METHODS AND RESULTS: A total of 14 820 hypertensive patients were included in the study. After 6 weeks with irbesartan 150mg od, in terms of their response to treatment, 8861 (61.9%) were normalised (DBP <90mm Hg), 1963 (13.7%) non-normalised responders (DBP > or = 90mm Hg with a decrease in DBP > or = 10mm Hg) and 3154 (22%) non-normalised non-responders (DBP > or = 90mm Hg with a decrease in DBP <10mm Hg); 842 patients did not respect the protocol and could not be evaluated. The 1963 non-normalised responders were randomly assigned at week 6 to either irbesartan 150mg od (n = 963) or irbesartan 300mg od (n = 1000) for 5 weeks. A greater reduction in mean DBP was found in the group treated with irbesartan 300mg (p < 0.001). There were no significant differences in terms of number or severity of adverse events between the two groups of patients.

Drug prescriptions and referral to cardiac rehabilitation after acute coronary events: comparison between men and women in the French PREVENIR Survey.

BACKGROUND AND AIM: The problem of a possible gender bias in coronary heart disease management is still controversial. We studied gender differences in secondary preventive drug prescriptions and in referral to cardiac rehabilitation after acute coronary events in France. METHODS: An observational survey was carried out in 1998-1999 in 150 French intensive cardiac care units. A sample of 2626 consecutive patients admitted for myocardial infarction or unstable angina and alive at discharge was included. Data were retrospectively collected from medical records after discharge. RESULTS: The sample was composed of 1921 men and 705 women. At discharge, antiplatelet agents were prescribed in 93.4% of men and 91.5% of women (p=0.09), beta-blockers in 73.4% and 63.7% (p<0.0001), angiotensin-converting enzyme (ACE) inhibitors in 39.9% and 44.3% (p<0.05), and statins in 47.0% and 40.7% (p<0.01). The percentage of subjects referred to a cardiac rehabilitation program at discharge was 26.2% in men and 15.5% in women (p<0.0001). In multivariate analysis, taking into account confounding factors, gender did not appear as an independent determinant of drug prescriptions. Conversely, being a woman was independently associated with a lower probability to be referred to a cardiac rehabilitation program at discharge (adjusted female-to-male odds ratio: 0.44 (95% confidence interval: [0.31-0.64], p<0.0001). CONCLUSIONS: In this study, gender was not an independent determinant of secondary preventive drug prescriptions after acute coronary events. Conversely, we found a gender bias in referral to cardiac rehabilitation programs at discharge.