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Journal articles on the topic "QT 256"
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PICCIRILLO, Gianfranco, Giuseppe GERMANÒ, Raffaele QUAGLIONE, Marialuce NOCCO, Filippo LINTAS, Marco LIONETTI, Antonio MOISÈ, Maddalena RAGAZZO, Vincenzo MARIGLIANO, and Mauro CACCIAFESTA. "QT-interval variability and autonomic control in hypertensive subjects with left ventricular hypertrophy." Clinical Science 102, no. 3 (February 14, 2002): 363–71. http://dx.doi.org/10.1042/cs1020363.
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Left ventricular hypertrophy is a risk factor for sudden death. Malignant ventricular arrhythmias originate from altered cardiac repolarization. Ample data have described spatial abnormalities in cardiac repolarization [QT interval (QT) dispersion] in subjects with hypertension; more data are needed on temporal changes. This study was designed to assess the QT variability index (QTVI), the slope between QT and the RR interval (QT-RRslope) and spectral QT variability in subjects with arterial hypertension. The results were compared with those from a population at high risk of sudden death, i.e. patients with hypertrophic cardiomyopathy (HCM) who had received an implantable cardioverter/defibrillator (ICD), and those from normotensive control subjects. A total of 44 hypertensive subjects, six patients with HCM and an ICD and 33 control subjects underwent simultaneous short-term recording (256 beats) of QT, RR and systolic blood pressure variability, in the supine position, during controlled breathing. QTVI and spectral components of QT variability in the hypertensive group were significantly higher than in normotensive control subjects (P < 0.001), but significantly lower than in patients with HCM and an ICD (P < 0.001). The severity of left ventricular hypertrophy correlated significantly with QTVI and the ratio of low-frequency (LF) to high-frequency (HF) power obtained from the RR variability spectra (RRLF/HF, slope = 0.24, P < 0.05; QTVI, slope = 4.06, P < 0.0001; intercept, slope = 2.40, P < 0.05; χ2 = 38.8; P < 0.0001). The QT-RR slope was significantly higher only in patients with HCM and an ICD (P < 0.001). In conclusion, the increased QTVI and the correlation of this index with left ventricular hypertrophy indicates that hypertension increases temporal cardiac repolarization abnormalities. At the level of the cardiac sinus node, this alteration is associated with increased sympathetic and reduced vagal modulation. As already noted in patients with HCM, the increased QTVI could be a factor responsible for triggering malignant ventricular arrhythmias in subjects with hypertension.
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Laiche, Adolph J. "Effects of Rate and Repeat Application of Flurprimidol on the Growth of Photinia × fraseri and Ilex crenata ‘Compacta’." Journal of Environmental Horticulture 6, no. 4 (December 1, 1988): 114–18. http://dx.doi.org/10.24266/0738-2898-6.4.114.
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Flurprimidol, α-(1-Methylethyl)-α-[4-(trifluoromethoxy)phenyl]-5-pyrimidine-methanol, was applied to three month plants of Photinia × fraseri in 5.6 L (6 qt) containers and Ilex crenata ‘Compacta’ in 2.8 L (3 qt) containers as foliar sprays at 0, 33, 66, 132, 264, 528, 1056, 2112, 4224, and 8448 ppnl. Growth-medium drench applications with flurprimidol were applied at 0, 2, 4, 8, 16, 32, 64, 128, 256, and 512 ppm solution, 0.5 L (17 oz) per 5.6 L (6 qt) container to Photinia. The initial foliar spray treatments and the growth medium drench treatments were applied on July 14, 1983. All test plants were planted in soil on December 9, 1983. Foliar spray treatments were repeated on July 19, 1985. Flurprimidol at low concentrations as a spray and drench substantially reduced plant size with little or no phytotoxicity. Duration of growth suppression increased as rate increased. Flurprimidol at low rates reduced growth for the remainder of the growing season in which it was applied. At higher rates growth was also reduced in the following growing season. Minor leaf distortion of smaller leaves was obtained at low rates and leaf distortion appeared to increase slightly at higher rates. Shoot growth after the effects of flurprimidol were no longer apparent appeared normal. Results indicate that flurprimidol alone and in conjunction with pruning can be helpful in maintaining woody landscape plants to a desirable size.
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Schulman, L. L., and Y. Enson. "Role of cyclooxygenase inhibition and hyperoxia in regulating pulmonary perfusion in dogs." American Journal of Physiology-Heart and Circulatory Physiology 268, no. 4 (April 1, 1995): H1521—H1530. http://dx.doi.org/10.1152/ajpheart.1995.268.4.h1521.
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To assess the roles of cyclooxygenase inhibition and hyperoxia in regulating pulmonary perfusion, we studied 13 dogs with diffuse granulomatous lung disease (DGLD) and 13 normal dogs. Baseline observations were obtained at fractional inspired O2 (FIO2) 0.21 and 1.0 and repeated after infusion of meclofenamate (Mec; n = 8) or saline (n = 5). Resistance to flow was evaluated from the pulmonary end-diastolic gradient (PDG) and by ohmic pulmonary vascular resistance (PVR). Distribution of blood flow was evaluated with sulfur hexafluoride in DGLD and with multiple inert gas alveolar ventilation-perfusion (VA/Q) plots in normal dogs. Before infusion, there were no differences between the saline and Mec groups at either FIO2. Saline induced no significant changes at either FIO2. After Mec in DGLD, PDG at FIO2 0.21 rose from 4 +/- 2 to 6 +/- 4 mmHg (P < 0.04), PVR increased from 297 +/- 98 to 484 +/- 181 dyn.s.cm-5.m-2 (P < 0.01), whereas shunt flow (Qs/Qt) fell form 13.6 +/- 12.0 to 6.2 +/- 5.3% (P < 0.03). At FIO2 1.0 PDG rose from 3 +/- 2 to 4 +/- 3 mmHg (P < 0.02), PVR increased from 262 +/- 78 to 374 +/- 139 dyn.s.cm-5.m-2 (P < 0.01), whereas Qs/Qt fell from 14.5 +/- 13.3 to 6.4 +/- 5.2% (P < 0.02). After Mec in normal dogs, PDG at FIO2 0.21 rose from 3 +/- 1 to 4 +/- 1 mmHg (P < 0.015) and PVR increased from 256 +/- 92 to 340 +/- 101 dyn.s.cm-5.m-2 (P < 0.05); at FIO2 1.0 PDG and PVR were unchanged from preinfusion levels. In normal dogs, no parameters of VA/Q changed significantly with hyperoxia or Mec. These data suggest that perivascular inflammation enhances perfusion in DGLD by elaboration of vasodilator prostaglandins (PG). By inhibiting PG synthesis, Mec selectively increases resistance in diseased lung at FIO2 0.21 and lowers Qs/Qt. In contrast, there was vasoconstriction without flow redistribution in normal dogs, suggesting that vasodilator PGs contribute to the low tone in the normal pulmonary bed. The vasodilation without flow redistribution in both models during hyperoxia after Mec suggests an effect of O2 that is related neither to PG synthesis nor to hypoxic vasoconstriction.
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Herrero-Morant, A., J. Zubiaur-Zamacola, A. Margarida-de Castro, R. Pérez-Barquín, and R. Blanco. "POS1148 OPTIMAL CUT-OFF POINT FOR ELECTROCARDIOGRAM IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS ON HYDROXYCHLOROQUINE THERAPY." Annals of the Rheumatic Diseases 82, Suppl 1 (May 30, 2023): 904. http://dx.doi.org/10.1136/annrheumdis-2023-eular.4462.
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BackgroundHydroxychloroquine (HCQ) is a widely used drug in Systemic Lupus Erythematosus (SLE) that can cause cardiac alterations such as arrhythmic events in the short-term and dose-dependent cardiomyopathy in the medium to long-term. The cardiological implications of HCQ accumulation in these patients in the medium to long-term is unknown.ObjectivesTo assess the optimal cut-off point for electrocardiogram (ECG) in patients with SLE on HCQ therapy to prevent arrhythmic complications.MethodsSingle university hospital observational study of all consecutive SLE patients who had an ECG at baseline and at least one ECG at follow-up. New conduction disturbances were assessed by ECG, defined as atrioventricular block, bundle branch block or QT interval prolongation. ECGs were extracted from the medical record and interpreted at baseline and for 15.2 years (95%CI 13.24-17.16) of follow-up. We defined cumulative HCQ (cHCQ) as the total grams of HCQ that had been administered. A Receiver Operating Characteristic (ROC) curve analysis was performed to determine the optimal cut-off point for sensitivity and specificity.ResultsWe studied 105 (93 female/12 male) SLE patients with a mean (±SD) age of 61.8±14.9 years. The mean daily dose of HCQ in our sample was 256 mg per day (Table 1). The ROC curve showed a moderate diagnostic ability for new conduction disturbances with an area under the curve of 0.69 (95% CI 0.59 - 0.77) (Figure 1). The highest efficacy cut-off point was cHCQ: 4097g (Sensitivity 15%; Specificity 100%) and the optimal cut-off point was cHCQ: 901g (Sensitivity 85%; Specificity 52.9%). This cut-off point was reached with a mean HCQ treatment in our sample of 9.7 years. High grade atrio-ventricular block was found in 5 patients. In all of them the cHCQ dose was over 901g.ConclusionAccording to our study, 901g of cHCQ dose is a good cut-off point for performing a protocolized ECG to rule out cardiac conduction disturbances in patients with SLE and chronic HCQ treatment. This is equivalent to 9.7 years of treatment with the mean HCQ dose use in our sample.Table 1.Clinical characteristics of Systemic Lupus Erythematosus patientsGeneral characteristicsGlobal (N=105)Current age (mean ± SD)61.8 ± 14.9Years of SLE evolution (mean ± SD)16.3 ± 10.3Sex, n (%)93 (88.6)Diabetes Mellitus, n (%)15 (14.4)Hypertension, n (%)58 (55.2)Dyslipidaemia, n (%)47 (45.2)Chronic renal failure, n (%)10 (9.6)Obesity, n (%)8 (7.8)Alcohol consumption, n (%)3 (2.9)Smoking history, n (%)41 (39.0)SLE treatmentHCQ dose in mg/day (mean ± SD)256 ± 87.2Time in HCQ in months (mean ± SD)149.8 ± 111.9Cumulative HCQ dose in grams (mean ± SD)1154.94 ± 946.10Cumulative HCQ dose in grams, median (IQR)913.1 (474, 1473)Prednisone, n (%)30 (28.6)Prednisone dose in mg/day (mean ± SD)17.3 ± 16.8Other immunosuppressant, n (%)14 (13.3)Abbreviations:HCQ: Hydroxychloroquine, SLE: Systemic Lupus ErythematosusFigure 1.Receiver Operating Characteristic (ROC) curve on cumulative hydroxychloroquine dose and new conduction disturbancesREFERENCES:NIL.Acknowledgements:NIL.Disclosure of InterestsAlba Herrero-Morant: None declared, Jon Zubiaur-Zamacola: None declared, Adrián Margarida-de Castro: None declared, Raquel Pérez-Barquín: None declared, Ricardo Blanco Speakers bureau: Abbvie, Pfizer, Roche, Lilly, Bristol-Myers, Janssen, Galapagos and MSD, Consultant of: Abbvie, Pfizer, Roche, Lilly, Bristol-Myers, Janssen and MSD, Grant/research support from: Abbvie, MSD, Novartis and Roche.
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Yuan, Xiaoguang, Yida Yang, Weifeng Li, and Chengshan Wang. "Provenance of Triassic Xiazijie Fan-Delta in Junggar Basin, Northwestern China: Insights from U-Pb Dating of Detrital Zircons." Minerals 13, no. 4 (March 26, 2023): 467. http://dx.doi.org/10.3390/min13040467.
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Abundant hydrocarbon resources were discovered in the Xiazijie fan-delta in the Triassic Baikouquan Formation in Mahu sag, Junggar basin. However, the maximum depositional age of Baikouquan Formation and provenance of this fan-delta are still unclear, which would be unfavourable for further hydrocarbon exploration. In this study, we used detrital zircon U-Pb dating and composition statistics of conglomerate clast and sandstone grain from Baikouquan Formation to constrain the maximum depositional age and provenance of the Xiazijie fan-delta. The results showed that (1) the conglomerate clast compositions of Xiazijie fan-delta mainly consisted of tuff and intermediate-felsic magmatic rocks, and sandstone samples could be classified as litharenite type with the lithic fragments were almost entirely volcanic lithic fragments; (2) the average Qt:F:L values of sandstone samples (M152-S1 and M152-S2) were 26:7:67 and 21:8:71, respectively, and they plotted in the magmatic arc domain in the Qt-F-L ternary diagram, indicating the tectonic setting of source area of Xiazijie fan-delta was magmatic arc; (3) M152-S1 yielded U-Pb ages ranging from 417 Ma to 253 Ma, with a dominant age peak at 313 Ma and two secondary age peaks at 411 Ma and 268 Ma, respectively, while M152-S2 yielded U-Pb ages ranging from 467 Ma to 256 Ma, with a dominant age peak at 307 Ma and two secondary date peaks at 405 Ma and 262 Ma; (4) the mean age of youngest two zircon grains of M152-S1 was 254.8 ± 4.7 Ma, while that of M152-S2 was 257.6 ± 3.8 Ma, suggesting the Baikouquan Formation might be deposited after the Changhsingian to Olenekian; (5) the magmatic rock ages of central West Junggar were distributed mostly between 450–260 Ma, with a dominant age peak at 307 Ma. The ages distribution between magmatic rock of central WJ and detrital zircons of M152-S1 and M152-S2 were similar, indicating the central WJ domain should be the major source area of the Xiazijie fan-delta; (6) the magmatic rock of Hakedun–Hongguleleng area in the Central WJ was characterized by a peak age at 305Ma, which was consistent with the peak ages of M152-S1 and M152-S2, indicating the Hakedun-Hongguleleng area was likely to be their major source area; and (7) one minor peak age at 411 Ma and another at 405 Ma were obtained from M152-S1 and M152-S2, respectively, and a zircon grain with Middle Ordovician age at 467 Ma was obtained from M152-S2, indicating Late Silurian–Early Devonian Chagankule pluton in the Saier Mountain and Ordovician Honggleleng ophiolite mélange in the Sharburt mountain were the minor source areas. This research has significant implications for stratigraphic correlation in Junggar basin and hydrocarbon exploration in the Xiazijie fan-delta conglomerate reservoir.
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Constable, P. D., K. W. Hinchcliff, J. Olson, and R. L. Hamlin. "Athletic heart syndrome in dogs competing in a long-distance sled race." Journal of Applied Physiology 76, no. 1 (January 1, 1994): 433–38. http://dx.doi.org/10.1152/jappl.1994.76.1.433.
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The cardiac effects of endurance training were evaluated by cardiac auscultation and electrocardiographic examination of 48 heavily trained sled dogs (3,000–5,000 km of training), 18 lightly trained sled dogs (300–800 km of training), 19 untrained sled dogs, and 14 mongrel dogs. A grade I-II/VI early- to midsystolic cardiac murmur was auscultated with increasing frequency as training level increased. The QRS duration (66.1 +/- 7.4 ms) and QT interval (236 +/- 20 ms) were significantly (P < 0.05) longer in heavily trained sled dogs than in mongrel dogs (QRS, 60.6 +/- 4.6; QT, 219 +/- 11 ms). A long QT interval (> 250 ms) was observed in 8 (16.7%) heavily trained dogs but not in the other groups. A significant rightward shift in the mean electrical axis of ventricular depolarization in the frontal plane was observed in heavily trained sled dogs. The auscultatory and electrocardiographic findings in heavily trained sled dogs were remarkably similar to those reported in elite human endurance athletes, suggesting that endurance-trained sled dogs provide a naturally occurring model for the athletic heart syndrome.
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Shtrygol’, Sergiy, Olga Koiro, Olesia Kudina, Olga Tovchiga, Tetiana Yudkevych, and Denys Oklei. "The influence of non-steroidal anti-inflammatory drugs with different mechanisms of action on the course of stress reaction, the functional state of kidneys, liver, and heart on the model of acute general cooling." ScienceRise: Pharmaceutical Science, no. 2(36) (April 29, 2022): 46–55. http://dx.doi.org/10.15587/2519-4852.2022.255797.
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Inhibitors of the arachidonic acid cascade have significant potential as the agents for the prevention of severe cold injuries. The results of the previous studies have demonstrated the pronounced frigoprotective properties of certain non-steroidal anti-inflammatory drugs, primarily diclofenac sodium, etoricoxib, darbufelone mesylate, under the conditions of acute general cooling.
The aim of the study: to investigate the effect of non-steroidal anti-inflammatory drugs with various mechanisms of action on the course of the stress reaction, the functional state of the kidneys, liver, and heart using the model of acute general cooling.
Materials and Methods: The experiment was carried out using 35 outbreed male rats weighing 256±5 g. The studied drugs were administered intragastrically 30 minutes before cold injury modelling: diclofenac sodium at a dose of 7 mg/kg, etoricoxib at a dose of 5 mg/kg, darbufelone mesylate at a dose of 20 mg/kg. Acute general cooling was induced by exposure at –18 °C for 2 hours. The efficacy of the studied drugs was evaluated by the values as follows: the body temperature (measured rectally), the course of a stress reaction according to the criteria of “the stress triad”, the functional state of the kidney and liver according to the changes in the blood serum biochemical parameters, the functional state of the heart according to the electrocardiogram.
Results: It was found that etoricoxib and darbufelone mesylate, and especially diclofenac sodium, demonstrate frigoprotective properties, reducing the severity of hypothermia, have stress-protective activity and a beneficial effect on the functional state of the kidneys. All investigated non-steroidal anti-inflammatory drugs prevent a decrease in myocardial contractility (by the effect on the systolic index) and lengthening of the QT interval caused by acute cold injury. Diclofenac sodium, unlike etoricoxib and darbufelone mesylate, does not enhance the effect of acute general cooling on intraventricular conduction. Under acute exposure to cold, no significant changes in the functional state of the liver were observed, including the groups receiving the nonsteroidal anti-inflammatory medicines.
Conclusions: The prophylactic administration of the arachidonic acid cascade inhibitors, especially the non-selective COX-2 inhibitor diclofenac sodium, reduces the severity of the stress response, contributes to the maintenance of the renal and cardiac function. There are no significant changes in the functional state of the liver under conditions of the experiment
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Breen, P. H., P. T. Schumacker, J. Sandoval, I. Mayers, L. Oppenheimer, and L. D. Wood. "Increased cardiac output increases shunt: role of pulmonary edema and perfusion." Journal of Applied Physiology 59, no. 4 (October 1, 1985): 1313–21. http://dx.doi.org/10.1152/jappl.1985.59.4.1313.
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In low-pressure pulmonary edema increased cardiac output (QT) increases shunt (Qs/QT); we tested whether the mechanism is an increase in extravascular lung water in turn mediated by the accompanying increase in microvascular pressure. In six pentobarbital sodium-anesthetized dogs ventilated with O2 we administered oleic acid into the right atrium. From base line to 2 h post-oleic acid we measured concurrent significant increases in Qs/QT (6–29%, O2 technique) and extravascular thermal volume (ETV, 2.6–7.1 ml/g dry intravascular blood-free lung wt, thermal-green dye indicator technique) that were stable by 90 min. Then, bilateral femoral arteriovenous fistulas were opened and closed in 30-min periods to cause reversible increases in QT and associated Qs/QT. When fistulas were open the time-averaged QT increased from 5.1 to 6.9 min (P less than 0.05), the simultaneous Qs/QT rose from 30.7 to 38.4% (P less than 0.05), but ETV did not increase. We conclude that increasing lung edema does not account for our rise in Qs/QT when QT increased.
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Christensen, Louise, J. Rick Turner, Gregory M. Peterson, Mark Naunton, Jackson Thomas, Kwang Choon Yee, and Sam Kosari. "Identification of Risk of QT Prolongation by Pharmacists When Conducting Medication Reviews in Residential Aged Care Settings: A Missed Opportunity?" Journal of Clinical Medicine 8, no. 11 (November 4, 2019): 1866. http://dx.doi.org/10.3390/jcm8111866.
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QT interval prolongation is associated with torsade de pointes and sudden cardiac death. QT prolongation can be caused by many drugs that are commonly prescribed in elderly residential aged care populations. The aim of this study was to investigate the prevalence of use of QT-prolonging drugs and to identify interventions made by pharmacists to reduce the risk of QT prolongation when conducting medication reviews in aged care. A retrospective analysis of 400 medication reviews undertaken by Australian pharmacists in aged care settings was conducted. The assessment included the risk of QT prolongation due to prescribed medications and other risk factors and the recommendations made by pharmacists to reduce the risk of QT prolongation. There was a high prevalence of the use of QT-prolonging medication, with 23% of residents (92 out of 400) taking at least one medication with a known risk of QT prolongation. Amongst the 945 prescribed drugs with any risk of QT prolongation, antipsychotics were the most common (n = 246, 26%), followed by antidepressants (19%) and proton pump inhibitors (13%). There appeared to be low awareness amongst the pharmacists regarding the risk of QT prolongation with drugs. Out of 400 reviews, 66 residents were categorised as high risk and were taking at least one medication associated with QT prolongation; yet pharmacists intervened in only six instances (9%), mostly when two QT-prolonging medications were prescribed. There is a need to increase awareness amongst pharmacists conducting medication reviews regarding the risk factors associated with QT prolongation, and further education is generally needed in this area.
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Samura, Lisa, Cahaya Rosyidan, Mustamina Maulani, Suryo Prakoso, Bayu Satiyawira, Maman Djumantara, Onnie Ridaliani, Mulia Ginting, and Mohammad Apriniyadi. "Physical property comparison of polymeric KCl sludge composition and polyamine at different temperatures." IOP Conference Series: Earth and Environmental Science 1339, no. 1 (May 1, 2024): 012020. http://dx.doi.org/10.1088/1755-1315/1339/1/012020.
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Abstract Drilling mud is a fluid used to assist the drilling process. The composition and physical properties of the mud greatly influence a drilling operation. Drilling operations that penetrate formations with shale content have the potential to experience drilling problems related to shale hydration. To get a good ability to prevent shale hydration, mud is added with polymeric and polyamine KCl additives (shale inhibitors) with the aim of stabilizing shale in contact with drilling fluid, as well as preventing drill cuttings from forming colloids. The results obtained in the KCl polymer mud composition at temperatures of 80°F, 250°F, and 300°F for mud weight were 9.3 ppg, 9.1 ppg, and 9 ppg, respectively. Funnel viscosity was 40 sec/qt, 36 sec/qt, and 34 sec/qt. Tap rates were 4.8 cc, 6 cc, and 6.6 cc. Mud cake remained at 1 mm and pH also remained at 9. While the results obtained on polyamine mud composition at temperatures of 80°F, 250°F, and 300°F for mud weight were 9.2 ppg, 8.9 ppg, and 8.8 ppg, respectively. Funnel viscosity was 26 sec/qt, 20 sec/qt, and 17 sec/qt. Tap rate of 10 cc, 13.8 cc, and 15 cc. Mud cake of 1 mm, 2 mm, and 2 mm. pH remains at 9. The data obtained shows that the results of the physical properties of polymeric KCl mud are better than polyamine mud.
Dissertations / Theses on the topic "QT 256"
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Renoud-Grappin, Rémi. "Mesures neurophysiologiques de la motivation à poursuivre un effort physique." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCE027.
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Le manque d’activité physique est un problème de santé publique, avec des recommandations de pratique régulière d’exercice, notamment après des événements cardiaques comme un infarctus.Pourtant, beaucoup de personnes éprouvent une aversion pour l’effort physique, même conscientes de ses bienfaits. La motivation devient donc un facteur crucial pour encourager la pratique continue d’exercice, et la mesure de la motivation est essentielle pour comprendre et soutenir l'engagement dans l’activité physique. Si la motivation pendant un programme d’exercice est relativement bien étudiée, peu d’études portent sur la mesure de la motivation pendant l’exercice lui-même.Dans cette thèse, nous nous intéressons à la possibilité de mesurer objectivement la motivation à poursuivre un exercice physique. Les outils psychométriques de mesures de la motivation tels que les informations auto rapportées (questionnaires), le comportement, la psychophysiologie et l’activité cérébrale ne sont pas tous adaptés à une mesure au cours d'un effort physique. La technique EEG est prometteuse pour mesurer objectivement la motivation pendant l’exercice, notamment via les potentiels évoqués.La réalisation d’une revue systématique montre que peu d’études ont mesuré des potentiels évoqués pendant le pédalage. Parmi les 20 études incluses, toutes rapportent la faisabilité de mesurer des potentiels évoqués pendant le pédalage, dans des conditions variées d’intensité, de durée et de condition environnementale. Mais dans aucune étude, les potentiels évoqués mesurés n’étaient liés à la motivation. De ce fait, nous avons mis en place une étude afin d’étudier la faisabilité de mesurer des potentiels évoqués liés à la motivation pendant l’exercice. Vingt sujets on tété recrutés pour effectuer une tâche de motivation pendant que leur activité cérébrale était enregistrée durant deux sessions, l’une étant réalisée tout en pédalant sur un cyclo ergomètre à intensité modérée, et l’autre sans pédaler. Les résultats comportementaux et EEG soutiennent l’hypothèse de pouvoir utiliser les potentiels évoqués comme mesure objective de motivation pendant l’exercice.Quelques réflexions importantes sont à considérer pour aller plus loin. D’une part, les potentiels évoqués mesurés dans cette thèse étaient liés à la motivation pour la tâche, et non pas à la motivation à poursuivre l’exercice. Une version adaptée de la même tâche a été validée et pourrait permettre de lier les potentiels évoqués à la motivation pour l’effort de pédalage. D’autre part, la motivation à poursuivre un exercice physique ne se limite pas à une motivation guidée par des récompenses à court terme. L’utilisation de la réalité virtuelle pourrait aider à envisager une approche expérimentale qui compléterait l’approche actuelle, afin de développer des mesures objectives de motivation à poursuivre un exerciceThe lack of physical activity is a public health issue, with recommendations for regular exercise,particularly after cardiac events such as a heart attack. However, many people experience anaversion to physical effort, even when they are aware of its benefits. Motivation thus becomes acrucial factor in encouraging sustained exercise practice, and measuring motivation is essential tounderstanding and supporting engagement in physical activity. While motivation during an exerciseprogram has been relatively well studied, few studies have focused on measuring motivation duringthe exercise itself. In this thesis, we explore the possibility of objectively measuring motivation tocontinue physical exercise.In experimental neuroscience, motivation is often reduced to a set of brain responses and behaviorsoriented toward obtaining a reward. Psychometric tools for measuring motivation include self-reported data (questionnaires), behavior, psychophysiology, and brain activity. The EEG techniqueshows promise for objectively measuring motivation during exercise, particularly through event-related potentials (ERPs).A systematic review revealed that few studies have measured ERPs during cycling. Among the 20studies included, all demonstrated the feasibility of measuring ERPs during cycling under variousconditions of intensity, duration, and environmental factors. However, in none of these studies werethe ERPs measured linked to motivation. Therefore, we conducted a study to assess the feasibility ofmeasuring motivation-related ERPs during exercise. Twenty participants were recruited to completea motivation task while their brain activity was recorded during two sessions: one while cycling on acycle ergometer at moderate intensity, and the other without cycling. Behavioral and EEG resultssupport the hypothesis that ERPs can be used as an objective measure of motivation during exercise.Several important considerations must be addressed to move forward. On the one hand, the ERPsmeasured in this study are related to task motivation, which does not correspond to motivation tocontinue exercising. An adapted version of the same task has been validated and could help link ERPsto motivation for the effort of cycling. On the other hand, motivation to continue physical exercise isnot limited to motivation driven by short-term rewards. The use of virtual reality could help developan experimental approach that complements the current one, in order to develop objectivemeasures of motivation to continue exercise
Books on the topic "QT 256"
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Gregory, Heath, and Lee I-Min, eds. Physical activity epidemiology. 2nd ed. Champaign, IL: Human Kinetics, 2013.
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Vunjak, Novakovic Gordana, ed. Culture of cells for tissue engineering. New York, NY: Wiley, 2006.
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Christopher, Vaughan, ed. Play: How it shapes the brain, opens the imagination, and invigorates the soul. New York, NY: Avery, 2009.
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D, McArdle William, and Katch Frank I, eds. Introduction to nutrition, exercise, and health. 4th ed. Philadelphia: Lea & Febiger, 1993.
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Ellen, Annandale, and Hunt Kate 1959-, eds. Gender inequalities in health. Buckingham: Open University Press, 2000.
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1964-, Stensel David J., ed. Physical activity and health: The evidence explained. 2nd ed. Milton Park, Abingdon, Oxon: Routledge, 2009.
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Culture of Cells for Tissue Engineering. Wiley & Sons Australia, Limited, John, 2005.
Find full textBook chapters on the topic "QT 256"
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Schwartz, Peter J., and Lia Crotti. "Long and Short QT Syndromes." In Cardiac Electrophysiology: From Cell to Bedside, 935–46. Elsevier, 2014. http://dx.doi.org/10.1016/b978-1-4557-2856-5.00093-5.
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SHELDON, ROBERT S., and AHMAD HERSI. "Evolving Indications for Pacing: Hypertrophic Cardiomyopathy, Sleep Apnea, Long QT Syndromes, and Neurally Mediated Syncope Syndromes * *This study was supported in part by grant 73-1976 from the Canadian Institute for Health Research (CIHR)." In Clinical Cardiac Pacing, Defibrillation, and Resynchronization Therapy, 473–98. Elsevier, 2007. http://dx.doi.org/10.1016/b978-1-4160-2536-8.50020-0.
Full textConference papers on the topic "QT 256"
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Choopa, S., R. Sesham, and P. Nair. "G25(P) Drug induced short qt interval with use of anti-epileptic medications." In Royal College of Paediatrics and Child Health, Abstracts of the RCPCH Conference–Online, 25 September 2020–13 November 2020. BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health, 2020. http://dx.doi.org/10.1136/archdischild-2020-rcpch.14.
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Muylle, K., S. Wuyts, and P. Cornu. "4CPS-137 Prospective analysis of clinical pharmacist interventions for QT drug–drug interactions alongside clinical decision support." In 26th EAHP Congress, Hospital pharmacists – changing roles in a changing world, 23–25 March 2022. British Medical Journal Publishing Group, 2022. http://dx.doi.org/10.1136/ejhpharm-2022-eahp.156.
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Zaitseva, A. V., V. V. Serikov, and H. T. Oniani. "PSYCHOPHYSIOLOGICAL ASSESSMENT OF THE LABOR OF MEDICAL WORKERS IN ORGANIZATIONS WITH COVID-19." In The 16th «OCCUPATION and HEALTH» Russian National Congress with International Participation (OHRNC-2021). FSBSI “IRIOH”, 2021. http://dx.doi.org/10.31089/978-5-6042929-2-1-2021-1-212-216.
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Abstract. Introduction. High neuro-emotional stress among medical workers in organizations with the leading harmfulness of Covid-19 contributes to the formation of an unfavorable functional state, increases the risks of health disorders. The study of the characteristics of the psychophysiological reactions of the body will allow to substantiate the timing of work in a pandemic, which is quite relevant at the present time. The purpose of the research was, on the basis of comprehensive psychophysiological studies, to study the features of the formation of a functional state in medical personnel working in organizations with COVID-19 under the influence of stress factors of the labor process. Materials and methods. A physiological and hygienic assessment of the intensity of the labor process was carried out, psychophysiological changes were studied during 3 months of work in the «dangerous» zone. Statistical processing of the obtained data was carried out using the statistical programs Statistika 10, Microsoft Excel 2010. Results. The formation of neuropsychic stress in medical workers is reflected in changes in ECG indicators (prolongation of the QT interval, decrease in the voltage of the P and T waves) and systemic arterial pressure, an increase in the endurance coefficient (an indicator of detraining of the cardiovascular system), positive values of the Kerdo autonomic index (predominance of sympathetic influences) after 3 months of work in medical organizations with Covid-19. Conclusions. Nervous and emotional tension at work is the leading professional factor among nurses and doctors working in medical institutions with Covid-19 (hazard class 3, grade 3). Indicators of the cardiovascular system, reflecting the degree of adaptation of the body of medical workers to production activities, can be used to justify different periods of work in organizations with Covid-19.
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Yuen, Eunice, Maria Posada, Claire Smith, Katharine Thorn, Dale Greenwood, Michelle Burgess, Karim Benhadji, Demetrio Ortega, Louise Chinchen, and Jeffrey Suico. "Abstract B082: Evaluation of the effects of an oral Notch inhibitor, LY3039478, on QT interval, and absolute and pilot relative bioavailability studies conducted in healthy subjects." In Abstracts: AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; October 26-30, 2017; Philadelphia, PA. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1535-7163.targ-17-b082.
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Berry, C., I. Motta, E. Kazounis, K. Fielding, M. Dodd, BT Nyang'wa, and R. Moodliar. "24-week regimens for treatment of rifampicin-resistant tuberculosis: four-arm randomised trial." In MSF Scientific Days International 2022. NYC: MSF-USA, 2022. http://dx.doi.org/10.57740/8wq5-2b43.
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INTRODUCTION Rifamipcin-resistant tuberculosis (RR-TB) affects around 465,000 people each year globally. Current treatment is of 9-20 months’ duration; is toxic and poorly efficacious. TB-PRACTECAL is a multi-arm, 2-stage, randomised controlled, multi-country, non-inferiority trial comparing 24-week regimens to the locally approved standard of care (control). We report TB-PRACTECAL stage 1 and 2 outcomes as well as additional analyses from dropped arms. METHODS Participants 15 years and above with pulmonary RR-TB from Uzbekistan, South Africa, and Belarus were included regardless of HIV status or CD4 count. Patients were randomized in a 1:1:1:1 ratio in stage 1 and 1:1 in stage 2. Randomization lists were stratified according to trial site. The BPaL regimen was comprised of bedaquiline 400mg daily for 2 weeks then 200mg three times weekly for 22 weeks, pretomanid 200mg daily for 24 weeks, and linezolid 600mg daily for 16 weeks followed by 300mg daily for 8 weeks. BPaLM additionally contained moxifloxacin 400mg daily and BPaLC contained clofazimine 100mg daily. Treatment was administered daily under observation. Transition to stage 2 occurred after enrolment of 240 participants and BPaLM was found to be the most promising arm. Randomisation continued during transition and all participants continued their allocated regimen and were followed up to 108 weeks. A post-hoc analysis was conducted comparing the three investigational arms to control using the primary efficacy outcome: proportion of patients with unfavourable outcome (death, treatment discontinuation, treatment failure, recurrence, lost to follow-up) at 72 weeks. We also assessed the proportion of patients with grade =3 or serious adverse events (SAE) by 72 weeks and mean change in QT corrected using Fridericia’s formula (QTcF) at week 24. ETHICS This study was approved by the Ethics Review Board (ERB) of the London School of Hygiene and Tropical Medicine and the local ERBs in Uzbekistan, Belarus and South Africa; and by the MSF ERB. RESULTS In March 2021, TB-PRACTECAL was terminated for efficacy at which point, 552 patients were enrolled. In the modified intention-to-treat population (comprising all randomised patients dispensed study medication at least once, excluding patients who did not have microbiologically-proven RR-TB), 252 patients had reached 72 weeks of follow-up, 44.0% of whom were female and 22.6% were HIV positive. In the modified intention- to-treat population, the percentage of unfavourable outcomes was 48.5% (32/66) for control, 23.3% (14/60) for BPaL, 18.8% (12/64) for BPaLC, and 11.3% (7/62) for BPaLM. There were three recurrences in BPaL, one in BPaLC, and none in BPaLM. Percentage of Grade =3 or SAE were 19.4% (14/72; 16 events), 31.9% (23/72; 32 events) and 21.7% (15/69; 24 events) in BPaLM, BPaLC and BPaL respectively, compared with 58.9% (43/73; 69 events) in the control. Mean change in QTcF at week 24 was 27.0 milliseconds (ms), 40.2 ms, and 23.3 ms in BPaLM, BPaLC, and BPaL respectively; compared with 44.89 ms in the control. CONCLUSION 24-week all-oral regimens of bedaquiline, pretomanid and tapered-dose linezolid, with and without clofazamine or moxifloxacin are safe and efficacious in the treatment of RR-TB. Trial results show that treatment with BPaLM was more effective and had a better safety profile than the Control. BPaLC and BPaL were also highly effective. CONFLICTS OF INTEREST None declared.