218 research outputs found

    Sleep apnoea and the heart

    Get PDF
    Sleep apnoea is associated with significant daytime functioning impairment and marked cardiovascular morbidities, leading to a significant increase in mortality. Sympathetic activation, oxidative stress and systemic inflammation have been shown to be the main intermediary mechanisms associated with sleep apnoea and intermittent hypoxia. There are now convincing data regarding the association between hypertension, arrhythmias, coronary heart disease, heart failure, increased cardiovascular mortality and sleep apnoea. This has been evidenced in sleep apnoea patients and is supported by experimental data obtained in intermittent hypoxia. Whether treating sleep apnoea enables chronic cardiovascular consequences to be reversed is not fully established as regard coronary heart disease, arrhythmias and heart failure. In this late condition, complex bidirectional relationships occur, with obstructive sleep apnoea being a risk factor for heart failure whilst central sleep apnoea mainly appears as a consequence of heart failure. It remains to be established in adequately designed studies, i.e. large randomised controlled trials, whether treating sleep apnoea can improve heart failure morbidity and mortality

    Magnesium(II)-ATP Complexes in 1-Ethyl-3-Methylimidazolium Acetate Solutions Characterized by 31Mg β-Radiation-Detected NMR Spectroscopy

    Full text link
    The complexation of MgII with adenosine 5′-triphosphate (ATP) is omnipresent in biochemical energy conversion, but is difficult to interrogate directly. Here we use the spin-urn:x-wiley:14337851:media:anie202207137:anie202207137-math-0001 β-emitter 31Mg to study MgII-ATP complexation in 1-ethyl-3-methylimidazolium acetate (EMIM-Ac) solutions using β-radiation-detected nuclear magnetic resonance (β-NMR). We demonstrate that (nuclear) spin-polarized 31Mg, following ion-implantation from an accelerator beamline into EMIM-Ac, binds to ATP within its radioactive lifetime before depolarizing. The evolution of the spectra with solute concentration indicates that the implanted 31Mg initially bind to the solvent acetate anions, whereafter they undergo dynamic exchange and form either a mono- (31Mg-ATP) or di-nuclear (31MgMg-ATP) complex. The chemical shift of 31Mg-ATP is observed up-field of 31MgMg-ATP, in accord with quantum chemical calculations. These observations constitute a crucial advance towards using β-NMR to probe chemistry and biochemistry in solution

    The Market for Organic Coconut Oil in Germany and the United States

    Get PDF
    This market research paper has been prepared under the supervision of Prof. Dr. Wolfgang Veit of TH Köln and Prof. Dr. Carol Scovotti of University of Wisconsin-Whitewater in the course of the inter-university cross-border collaboration student research project “Export Opportunity Surveys (EOS)”. This study explores organic coconut oil export opportunities to the German and US markets

    Estimation of respiration rate and sleeping position using a wearable accelerometer

    Get PDF
    The 42nd Annual International Conferences of the IEEE Engineering in Medicine and Biology Society, EMBS Virtual Academy, 20-24 July 2020Wearable inertial sensors offer the possibility to monitor sleeping position and respiration rate during sleep, enabling a comfortable and low-cost method to remotely monitor patients. Novel methods to estimate respiration rate and position during sleep using accelerometer data are presented, with algorithm performance examined for two sensor locations, and accelerometer-derived respiration rate compared across sleeping positions. Eleven participants (9 male; aged: 47.82±14.14 years; BMI 30.9±5.27 kg/m 2 ; AHI 5.77±4.18) undergoing a scheduled clinical polysomnography (PSG) wore a tri-axial accelerometer on their chest and upper abdomen. PSG cannula flow and position data were used as benchmark data for respiration rate (breaths per minute, bpm) and position. Sleeping position was classified using logistic regression, with features derived from filtered acceleration and orientation. Accelerometer-derived respiration rate was estimated for 30 s epochs using an adaptive peak detection algorithm which combined filtered acceleration and orientation data to identify individual breaths. Sensor-derived and PSG respiration rates were then compared. Mean absolute error (MAE) in respiration rate did not vary between sensor locations (abdomen: 1.67±0.37 bpm; chest: 1.89±0.53 bpm; p=0.52), while reduced MAE was observed when participants lay on their side (1.58±0.54 bpm) compared to supine (2.43±0.95 bpm), p<; 0.01. MAE was less than 2 bpm for 83.6% of all 30 s windows across all subjects. The position classifier distinguished supine and left/right with a ROC AUC of 0.87, and between left and right with a ROC AUC of 0.94. The proposed methods may enable a low-cost solution for in-home, long term sleeping posture and respiration monitoring.European Research CouncilScience Foundation IrelandInsight Research Centre2020-10-06 JG: PDF replaced with correct versio

    Metalloprotein entatic control of ligand-metal bonds quantified by ultrafast x-ray spectroscopy

    Get PDF
    The multifunctional protein cytochrome c (cyt c) plays key roles in electron transport and apoptosis, switching function by modulating bonding between a heme iron and the sulfur in a methionine residue. This Fe-S(Met) bond is too weak to persist in the absence of protein constraints. We ruptured the bond in ferrous cyt c using an optical laser pulse and monitored the bond reformation within the protein active site using ultrafast x-ray pulses from an x-ray free-electron laser, determining that the Fe-S(Met) bond enthalpy is ~4 kcal/mol stronger than in the absence of protein constraints. The 4 kcal/mol is comparable with calculations of stabilization effects in other systems, demonstrating how biological systems use an entatic state for modest yet accessible energetics to modulate chemical function

    ERP correlates of motivating voices: quality of motivation and time-course matters

    Get PDF
    Here, we conducted the first study to explore how motivations expressed through speech are processed in real-time. Participants listened to sentences spoken in two types of well-studied motivational tones (autonomy-supportive and controlling), or a neutral tone of voice. To examine this, listeners were presented with sentences that either signaled motivations through prosody (tone of voice) and words simultaneously (e.g. ‘You absolutely have to do it my way’ spoken in a controlling tone of voice), or lacked motivationally biasing words (e.g. ‘Why don’t we meet again tomorrow’ spoken in a motivational tone of voice). Event-related brain potentials (ERPs) in response to motivations conveyed through words and prosody showed that listeners rapidly distinguished between motivations and neutral forms of communication as shown in enhanced P2 amplitudes in response to motivational when compared with neutral speech. This early detection mechanism is argued to help determine the importance of incoming information. Once assessed, motivational language is continuously monitored and thoroughly evaluated. When compared with neutral speech, listening to controlling (but not autonomy-supportive) speech led to enhanced late potential ERP mean amplitudes, suggesting that listeners are particularly attuned to controlling messages. The importance of controlling motivation for listeners is mirrored in effects observed for motivations expressed through prosody only. Here, an early rapid appraisal, as reflected in enhanced P2 amplitudes, is only found for sentences spoken in controlling (but not autonomy-supportive) prosody. Once identified as sounding pressuring, the message seems to be preferentially processed, as shown by enhanced late potential amplitudes in response to controlling prosody. Taken together, results suggest that motivational and neutral language are differentially processed; further, the data suggest that listening to cues signaling pressure and control cannot be ignored and lead to preferential, and more in-depth processing mechanisms

    Impact of Sleep Apnea on Cardioembolic Risk in Patients With Atrial Fibrillation: Data From the ESADA Cohort

    Get PDF
    Background and purpose: An accurate determination of the cardioembolic risk in patients with atrial fibrillation (AF) is crucial to prevent consequences like stroke. Obstructive sleep apnea (OSA) is a known risk factor for both AF and stroke. We aim to explore a possible association between OSA and an increased cardioembolic risk in patients with AF.Methods: We assessed data from the ESADA (European Sleep Apnea Database) cohort where patients with known AF and OSA were included. Parameters of OSA severity and related hypoxia like lowest Spo2 and 4% oxygen desaturation index were analyzed. Patients were stratified according to their cardioembolic risk estimated with the CHA2DS2-VASc score.Results: From the initial cohort of 14 646 patients, a final set of 363 patients were included in the analysis. Indices of hypoxia during sleep were associated with increased CHA2DS2-VASc score (4% oxygen desaturation index 17.9 versus 29.6 versus 30.5 events/hour and the lowest Spo2 81.2 versus 77.8 versus 77.5% for low, moderate, and high cardioembolic risk, respectively, PConclusions: These results support the potential role of OSA-related hypoxia in the risk for cardioembolic complications such as stroke in patients with AF.</p
    corecore