99 research outputs found
Efficacy of mental relaxation at workplace: assessing autonomic effects with transtelephonic approach
No full textMaintained autonomic responses to moderate exercise in hypertensives treated with lacidipine
No full textObjective. Excessive adrenergic responses have been reported in hypertensive patients treated with short-acting dihydropiridine calcium channel antagonists that might worsen cardiovascular risk. In this study we addressed whether lacidipine, a long-acting dihydropiridine, increases the sympathetic excitation produced by moderate dynamic exercise. Design. Because of the wide changes in autonomic drive during everyday life, the possible influence of antihypertensive regimens should be assessed not only at rest but also during spontaneous, behaviourally induced alterations of sympathovagal balance. This study was designed to test whether treatment with lacidipine might alter the autonomic response to supine moderate dynamic exercise. Methods. We studied 16 moderate hypertensive patients (arterial pressure 151/102 mmHg) at rest and during 30%, of nominal maximum recumbent bicycle exercise. The low frequency spectral component of RR interval and of systolic variability (Finapres) furnished markers of sympathetic modulation of the sinoatrial node and of the vasculature, respectively. Studies were performed during placebo and active treatment (lacidipine 4 mg per day). Results. Lacidipine treatment significantly reduces arterial pressure values at rest and during moderate dynamic exercise, without affecting RR interval and systolic arterial pressure variabilities, both at rest and during moderate exercise. Conclusions. In conclusion, spectral analysis of RR interval and systolic arterial pressure variabilities indicate that antihypertensive treatment with lacidipine is not associated to an excessive sympathetic drive during moderate exercise
Torque behavior of one-phase permanent magnet AC motor
No full textThis paper presents a detailed comparative study of two starting and running methods for a single-phase permanent magnet synchronous motor, equipped with a squirrel-cage rotor. The analysis of the motor performance is realized for a pulse width modulated (PWM) inverter fed motor and for a capacitor-start, capacitor-run motor. The developed approach may be extended to any 1-phase ac motor—induction, synchronous reluctance or synchronous permanent magnet
Line-start permanent-magnet motor: single-phase starting performance analysis
No full textThis paper presents a detailed quasi-steady-state approach to different torque components (average and pulsating) for a single-phase capacitor-run permanent-magnet (PM) motor. By employing average electromagnetic torque, and the expected envelope of the pulsating torque, an accurate prediction of starting torque components behavior is made. The quasi-steady-state analysis of the asynchronous performance of the single-phase capacitor-start capacitor-run PM motor is realized through a combination of symmetrical components and d-q axes theory. The developed approach is valid for any m-phase AC motor-induction, synchronous reluctance, or synchronous PM
HUWE1 controls MCL1 stability to unleash AMBRA1-induced mitophagy
No full textReceptor-mediated mitophagy is a crucial process involved in mitochondria quality control. AMBRA1 is a mitophagy receptor for the selective removal of damaged mitochondria in mammalian cells. A critical unresolved issue is how AMBRA1-mediated mitophagy is controlled in response to cellular stress. Here, we investigated the role of BCL2-family proteins on AMBRA1-dependent mitophagy and showed that MCL1 delays AMBRA1-dependent mitophagy. Indeed, MCL1 overexpression is sufficient to inhibit recruitment to mitochondria of the E3 Ubiquitin ligase HUWE1, a crucial dynamic partner of AMBRA1, upon AMBRA1-mediated mitophagy induction. In addition, we found that during mitophagy induced by AMBRA1, MCL1 levels decreased but were sustained by inhibition of the GSK-3β kinase, which delayed AMBRA1-mediated mitophagy. Also, we showed that MCL1 was phosphorylated by GSK-3β at a conserved GSK-3 phosphorylation site (S159) during AMBRA1-mediated mitophagy and that this event was accompanied by HUWE1-dependent MCL1 degradation. Altogether, our results demonstrate that MCL1 stability is regulated by the kinase GSK-3β and the E3 ubiquitin ligase HUWE1 in regulating AMBRA1-mediated mitophagy. Our work thus defines MCL1 as an upstream stress-sensitive protein, functional in AMBRA1-mediated mitophagy
Correction to: HUWE1 controls MCL1 stability to unleash AMBRA1-induced mitophagy
No full textAn amendment to this paper has been published and can be accessed via a link at the top of the paper
AMBRA1-mediated mitophagy counteracts oxidative stress and apoptosis induced by neurotoxicity in human neuroblastoma SH-SY5Y cells
No full textTherapeutic strategies are needed to protect dopaminergic neurons in Parkinson's disease (PD) patients. Oxidative stress caused by dopamine may play an important role in PD pathogenesis. Selective autophagy of mitochondria (mitophagy), mainly regulated by PINK1 and PARKIN, plays an important role in the maintenance of cell homeostasis. Mutations in those genes cause accumulation of damaged mitochondria, leading to nigral degeneration and early-onset PD. AMBRA1ActA is a fusion protein specifically expressed at the mitochondria, and whose expression has been shown to induce a powerful mitophagy in mammalian cells. Most importantly, the pro-autophagy factor AMBRA1 is sufficient to restore mitophagy in fibroblasts of PD patients carrying PINK1 and PARKIN mutations. In this study, we investigated the potential neuroprotective effect of AMBRA1-induced mitophagy against 6-hydroxydopamine (6-OHDA)- and rotenone-induced cell death in human neuroblastoma SH-SY5Y cells. We demonstrated that AMBRA1ActA overexpression was sufficient to induce mitochondrial clearance in SH-SY5Y cells. We found that apoptosis induced by 6-OHDA and rotenone was reversed by AMBRA1-induced mitophagy. Finally, transfection of SH-SY5Y cells with a vector encoding AMBRA1ActA significantly reduced 6-OHDA and rotenone-induced generation of reactive oxygen species (ROS). Altogether, our results indicate that AMBRA1ActA is able to induce mitophagy in SH-SY5Y cells in order to suppress oxidative stress and apoptosis induced by both 6-OHDA and rotenone. These results strongly suggest that AMBRA1 may have promising neuroprotective properties with an important role in limiting ROS-induced dopaminergic cell death, and the utmost potential to prevent PD or other neurodegenerative diseases associated with mitochondrial oxidative stress
Saint Antoine de Padoue, Sermons des dimanches et des fêtes. I. Du dimanche de la Septuagésime au dimanche de la Pentecôte. Introduction, traduction et notes par Valentin Strappazzon (coll. Sagesses chrétiennes). 2005
No full textHaquin André. Saint Antoine de Padoue, Sermons des dimanches et des fêtes. I. Du dimanche de la Septuagésime au dimanche de la Pentecôte. Introduction, traduction et notes par Valentin Strappazzon (coll. Sagesses chrétiennes). 2005. In: Revue théologique de Louvain, 37ᵉ année, fasc. 1, 2006. p. 107
Saint Antoine de Padoue, Sermons des dimanches et des fêtes. I. Du dimanche de la Septuagésime au dimanche de la Pentecôte. Introduction, traduction et notes par Valentin Strappazzon (coll. Sagesses chrétiennes). 2005
No full textHaquin André. Saint Antoine de Padoue, Sermons des dimanches et des fêtes. I. Du dimanche de la Septuagésime au dimanche de la Pentecôte. Introduction, traduction et notes par Valentin Strappazzon (coll. Sagesses chrétiennes). 2005. In: Revue théologique de Louvain, 37ᵉ année, fasc. 1, 2006. p. 107
Cardiac autonomic adjustement to normal human pregnancy : insight from spectral analysis of R-R interval and systolic arterial pressure variability
No full textOBJECTIVE: To assess the adaptation in autonomic control mechanisms that accompanies the marked haemodynamic changes, such as increases in cardiac size and output, that occur in the course of normal human pregnancy. DESIGN: We studied 14 healthy pregnant women (aged 30+/-1 years) before the 6th week (early stage) and within weeks 32-34 (late stage) of pregnancy, while they were at rest or in a state of active orthostatism (standing), which enhances sympathetic activity. METHODS: We used echocardiography to assess cardiac volumes and mass, and spectral analysis of the R-R interval and systolic arterial pressure variability to obtain indices of autonomic regulation of the circulation. This non-invasive methodology, recently validated with direct recordings of muscle sympathetic nerve activity, furnishes quantitative markers of sympathetic modulation of the sino-atrial node (low frequency component, LF in normalized units, nu), vagal modulation (high frequency component, HF in normalized units, nu) and the overall arterial pressure-heart rate baroreflex gain (alpha index). RESULTS: Late pregnancy was characterized by an increase in cardiac size and volumes and by a reduction of R-R interval, R-R interval variance and the alpha index, together with an increase in the LF/HF ratio (from 1.4+/-0.4 to 5.6+/-1.9). Changes in markers of autonomic modulation of the sino-atrial node normally induced by the standing position were blunted. CONCLUSIONS: The late stage of normal human pregnancy appears to be characterized by alterations in the autonomic control of the circulation and by attenuated responsiveness to active standing, possibly as a consequence of the accompanying increase in cardiac size
- …
