WorldWideScience

Sample records for rhythm association ehra

  1. Hypertension and cardiac arrhythmias: executive summary of a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; En Chiang, Chern; Williams, Bryan

    2017-10-01

    Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in HTN patients, especially in those with left ventricular hypertrophy (LVH), CAD, or HF. In addition, high doses of thiazide diuretics commonly used to treat HTN, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesaemia), contributing further to arrhythmias, while effective blood pressure control may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence and publishing a joint consensus document on HTN and cardiac arrhythmias, and providing up-to-date consensus recommendations for use in clinical practice. The ultimate judgment on the care of a specific patient must be made by the healthcare provider and the patient in light of all individual factors presented. This is an executive summary of the full document co-published by EHRA in EP-Europace. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

  2. Antithrombotic therapy in atrial fibrillation associated with valvular heart disease: a joint consensus document from the European Heart Rhythm Association (EHRA) and European Society of Cardiology Working Group on Thrombosis, endorsed by the ESC Working Group on Valvular Heart Disease, Cardiac Arrhythmia Society of Southern Africa (CASSA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Collet, Jean Philippe; Caterina, Raffaele de; Fauchier, Laurent; Lane, Deirdre A; Larsen, Torben B; Marin, Francisco; Morais, Joao; Narasimhan, Calambur; Olshansky, Brian; Pierard, Luc; Potpara, Tatjana; Sarrafzadegan, Nizal; Sliwa, Karen; Varela, Gonzalo; Vilahur, Gemma; Weiss, Thomas; Boriani, Giuseppe; Rocca, Bianca

    2017-11-01

    Atrial fibrillation (AF) is a major worldwide public health problem, and AF in association with valvular heart disease (VHD) is also common. However, management strategies for this group of patients have been less informed by randomized trials, which have largely focused on 'non-valvular AF' patients. Thrombo-embolic risk also varies according to valve lesion and may also be associated with CHA2DS2VASc score risk factor components, rather than only the valve disease being causal. Given marked heterogeneity in the definition of valvular and non-valvular AF and variable management strategies, including non-vitamin K antagonist oral anticoagulants (NOACs) in patients with VHD other than prosthetic heart valves or haemodynamically significant mitral valve disease, there is a need to provide expert recommendations for professionals participating in the care of patients presenting with AF and associated VHD. To address this topic, a Task Force was convened by the European Heart Rhythm Association (EHRA) and European Society of Cardiology (ESC) Working Group on Thrombosis, with representation from the ESC Working Group on Valvular Heart Disease, Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE) with the remit to comprehensively review the published evidence, and to publish a joint consensus document on the management of patients with AF and associated VHD, with up-to-date consensus recommendations for clinical practice for different forms of VHD. This consensus document proposes that the term 'valvular AF' is outdated and given that any definition ultimately relates to the evaluated practical use of oral anticoagulation (OAC) type, we propose a functional Evaluated Heartvalves, Rheumatic or Artificial (EHRA) categorization in relation to the type of OAC use in patients with AF, as follows: (i) EHRA Type 1 VHD, which refers

  3. Hypertension and cardiac arrhythmias: a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

    2017-06-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in hypertensive patients, especially in those with left ventricular hypertrophy (LVH) or HF. Also, some of the antihypertensive drugs commonly used to reduce blood pressure, such as thiazide diuretics, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesemia), further contributing to arrhythmias, whereas effective control of blood pressure may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between hypertension and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit to comprehensively review the available evidence to publish a joint consensus document on hypertension and cardiac arrhythmias, and to provide up-to-date consensus recommendations for use in clinical practice. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and the patient in light of all of the circumstances presented by that patient. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  4. Antithrombotic Therapy in Atrial Fibrillation Associated with Valvular Heart Disease: Executive Summary of a Joint Consensus Document from the European Heart Rhythm Association (EHRA) and European Society of Cardiology Working Group on Thrombosis, Endorsed by the ESC Working Group on Valvular Heart Disease, Cardiac Arrhythmia Society of Southern Africa (CASSA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Collet, Jean Philippe; de Caterina, Raffaele; Fauchier, Laurent; Lane, Deirdre A; Larsen, Torben B; Marin, Francisco; Morais, Joao; Narasimhan, Calambur; Olshansky, Brian; Pierard, Luc; Potpara, Tatjana; Sarrafzadegan, Nizal; Sliwa, Karen; Varela, Gonzalo; Vilahur, Gemma; Weiss, Thomas; Boriani, Giuseppe; Rocca, Bianca

    2017-12-01

    Management strategies for patients with atrial fibrillation (AF) in association with valvular heart disease (VHD) have been less informed by randomized trials, which have largely focused on ‘non-valvular AF’ patients. Thromboembolic risk also varies according to valve lesion and may also be associated with CHA2DS2-VASc score risk factor components, rather than only the valve disease being causal. Given the need to provide expert recommendations for professionals participating in the care of patients presenting with AF and associated VHD, a task force was convened by the European Heart Rhythm Association (EHRA) and European Society of Cardiology (ESC) Working Group (WG) on Thrombosis, with representation from the ESC WG on Valvular Heart Disease, Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE) with the remit to comprehensively review the published evidence, and to produce a consensus document on the management of patients with AF and associated VHD, with up-to-date consensus statements for clinical practice for different forms of VHD, based on the principles of evidence-based medicine. This is an executive summary of a consensus document which proposes that the term ‘valvular AF’ is outdated and given that any definition ultimately relates to the evaluated practical use of oral anticoagulation (OAC) type, we propose a functional EHRA (Evaluated Heartvalves, Rheumatic or Artificial) categorization in relation to the type of OAC use in patients with AF, as follows: (1) EHRA (Evaluated Heartvalves, Rheumatic or Artificial) type 1 VHD, which refers to AF patients with ‘VHD needing therapy with a vitamin K antagonist (VKA)’ and (2) EHRA (Evaluated Heartvalves, Rheumatic or Artificial) type 2 VHD, which refers to AF patients with ‘VHD needing therapy with a VKA or a non-VKA oral anticoagulant also taking

  5. Executive Summary: European Heart Rhythm Association Consensus Document on the Management of Supraventricular Arrhythmias: Endorsed by Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardiaca y Electrofisiologia (SOLAECE).

    Science.gov (United States)

    Katritsis, Demosthenes G; Boriani, Giuseppe; Cosio, Francisco G; Jais, Pierre; Hindricks, Gerhard; Josephson, Mark E; Keegan, Roberto; Knight, Bradley P; Kuck, Karl-Heinz; Lane, Deirdre A; Lip, Gregory Yh; Malmborg, Helena; Oral, Hakan; Pappone, Carlo; Themistoclakis, Sakis; Wood, Kathryn A; Young-Hoon, Kim; Lundqvist, Carina Blomström

    2016-01-01

    This paper is an executive summary of the full European Heart Rhythm Association (EHRA) consensus document on the management of supraventricular arrhythmias, published in Europace . It summarises developments in the field and provides recommendations for patient management, with particular emphasis on new advances since the previous European Society of Cardiology guidelines. The EHRA consensus document is available to read in full at http://europace.oxfordjournals.org.

  6. Health economics and the European Heart Rhythm Association.

    Science.gov (United States)

    Vardas, Panos; Boriani, Giuseppe

    2011-05-01

    The management of healthcare is becoming extremely complex in developed countries, as a result of increasing age of the population and increasing costs of care, coupled with diminishing resources due to global financial crisis. This situation threatens access to appropriate care, and a more or less explicit rationing of some types of treatment may occur in 'real world' clinical practice. This is particularly true for those treatments or interventions with a relatively high up-front cost, such as cardioverter defibrillators, devices for cardiac resynchronization therapy or ablation procedures for atrial fibrillation. The European Heart Rhythm Association (EHRA) is strongly convinced that the skills of electrophysiologists and cardiologists responsible for the management of rhythm disorders have to evolve, also embracing the knowledge of health economics, clinical epidemiology, health-care management and outcome research. These disciplines do not belong to what is considered as the conventional cultural background of physicians, but knowledge of comparative cost effectiveness and of other economic approaches nowadays appears fundamental for a dialogue with a series of stakeholders, such as policy makers, politicians, and administrators, involved in budgeting the activity of hospitals and health-care services, as well as in approaching health technology assessment.

  7. Updated European Heart Rhythm Association practical guide on the use of non-vitamin-K antagonist anticoagulants in patients with non-valvular atrial fibrillation: Executive summary.

    Science.gov (United States)

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Diener, Hans-Christoph; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2017-07-14

    In 2013, the European Heart Rhythm Association (EHRA) published a Practical Guide on the use of non-VKA oral anticoagulants (NOACs) in patients with atrial fibrillation (AF) (Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, Sinnaeve P, Camm AJ, Kirchhof P, European Heart Rhythm A. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-651; Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, Sinnaeve P, Camm AJ, Kirchhof P. EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary. Eur Heart J 2013;34:2094-2106). The document received widespread interest, not only from cardiologists but also from neurologists, geriatricians, and general practitioners, as became evident from the distribution of >350 000 copies of its pocket version (the EHRA Key Message Booklet) world-wide. Since 2013, numerous new studies have appeared on different aspects of NOAC therapy in AF patients. Therefore, EHRA updated the Practical Guide, including new information but also providing balanced guiding in the many areas where prospective data are still lacking. The outline of the original guide that addressed 15 clinical scenarios has been preserved, but all chapters have been rewritten. Main changes in the Update comprise a discussion on the definition of 'non-valvular AF' and eligibility for NOAC therapy, inclusion of finalized information on the recently approved edoxaban, tailored dosing information dependent on concomitant drugs, and/or clinical characteristics, an expanded chapter on neurologic scenarios (ischaemic stroke or intracranial haemorrhage under NOAC), an updated anticoagulation card and more specifics on start-up and follow-up issues. There are also many new flow charts, like on appropriate switching between anticoagulants (VKA to NOAC or vice versa), default scenarios for

  8. Integrating new approaches to atrial fibrillation management: the 6th AFNET/EHRA Consensus Conference.

    Science.gov (United States)

    Kotecha, Dipak; Breithardt, Günter; Camm, A John; Lip, Gregory Y H; Schotten, Ulrich; Ahlsson, Anders; Arnar, David; Atar, Dan; Auricchio, Angelo; Bax, Jeroen; Benussi, Stefano; Blomstrom-Lundqvist, Carina; Borggrefe, Martin; Boriani, Giuseppe; Brandes, Axel; Calkins, Hugh; Casadei, Barbara; Castellá, Manuel; Chua, Winnie; Crijns, Harry; Dobrev, Dobromir; Fabritz, Larissa; Feuring, Martin; Freedman, Ben; Gerth, Andrea; Goette, Andreas; Guasch, Eduard; Haase, Doreen; Hatem, Stephane; Haeusler, Karl Georg; Heidbuchel, Hein; Hendriks, Jeroen; Hunter, Craig; Kääb, Stefan; Kespohl, Stefanie; Landmesser, Ulf; Lane, Deirdre A; Lewalter, Thorsten; Mont, Lluís; Nabauer, Michael; Nielsen, Jens C; Oeff, Michael; Oldgren, Jonas; Oto, Ali; Pison, Laurent; Potpara, Tatjana; Ravens, Ursula; Richard-Lordereau, Isabelle; Rienstra, Michiel; Savelieva, Irina; Schnabel, Renate; Sinner, Moritz F; Sommer, Philipp; Themistoclakis, Sakis; Van Gelder, Isabelle C; Vardas, Panagiotis E; Verma, Atul; Wakili, Reza; Weber, Evelyn; Werring, David; Willems, Stephan; Ziegler, André; Hindricks, Gerhard; Kirchhof, Paulus

    2018-01-02

    There are major challenges ahead for clinicians treating patients with atrial fibrillation (AF). The population with AF is expected to expand considerably and yet, apart from anticoagulation, therapies used in AF have not been shown to consistently impact on mortality or reduce adverse cardiovascular events. New approaches to AF management, including the use of novel technologies and structured, integrated care, have the potential to enhance clinical phenotyping or result in better treatment selection and stratified therapy. Here, we report the outcomes of the 6th Consensus Conference of the Atrial Fibrillation Network (AFNET) and the European Heart Rhythm Association (EHRA), held at the European Society of Cardiology Heart House in Sophia Antipolis, France, 17-19 January 2017. Sixty-two global specialists in AF and 13 industry partners met to develop innovative solutions based on new approaches to screening and diagnosis, enhancing integration of AF care, developing clinical pathways for treating complex patients, improving stroke prevention strategies, and better patient selection for heart rate and rhythm control. Ultimately, these approaches can lead to better outcomes for patients with AF. © The Author 2018. Published by Oxford University Press on behalf of the European Society of Cardiology.

  9. Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options--a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

    DEFF Research Database (Denmark)

    Kirchhof, Paulus; Lip, Gregory Y H; Van Gelder, Isabelle C

    2012-01-01

    the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper...... covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section...

  10. Statistics on the use of cardiac electronic devices and electrophysiological procedures in the European Society of Cardiology countries: 2014 report from the European Heart Rhythm Association.

    Science.gov (United States)

    Raatikainen, M J Pekka; Arnar, David O; Zeppenfeld, Katja; Merino, Jose Luis; Levya, Francisco; Hindriks, Gerhardt; Kuck, Karl-Heinz

    2015-01-01

    There has been large variations in the use of invasive electrophysiological therapies in the member countries of the European Society of Cardiology (ESC). The aim of this analysis was to provide comprehensive information on cardiac implantable electronic device (CIED) and catheter ablation therapy trends in the ESC countries over the last five years. The European Heart Rhythm Association (EHRA) has collected data on CIED and catheter ablation therapy since 2008. Last year 49 of the 56 ESC member countries provided data for the EHRA White Book. This analysis is based on the current and previous editions of the EHRA White Book. Data on procedure rates together with information on economic aspects, local reimbursement systems and training activities are presented for each ESC country and the five geographical ESC regions. In 2013, the electrophysiological procedure rates per million population were highest in Western Europe followed by the Southern and Northern European countries. The CIED implantation and catheter ablation rate was lowest in the Eastern European and in the non-European ESC countries, respectively. However, in some Eastern European countries with relative low gross domestic product procedure rates exceeded those of some wealthier Western countries, suggesting that economic resources are not the only driver for utilization of arrhythmia therapies. These statistics indicate that despite significant improvements, there still is considerable heterogeneity in the availability of arrhythmia therapies across the ESC area. Hopefully, these data will help identify areas for improvement and guide future activities in cardiac arrhythmia management. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  11. EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary.

    Science.gov (United States)

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2013-07-01

    New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in specific clinical situations. This text is an executive summary of a practical guide that the European Heart Rhythm Association (EHRA) has assembled to help physicians in the use of the different NOACs. The full text is being published in EP Europace. Practical answers have been formulated for 15 concrete clinical scenarios: (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring compliance of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (ix) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease; (xiii) cardioversion in a NOAC-treated patient; (xiv) patients presenting with acute stroke while on NOACs; (xv) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA web site with the latest updated information accompanies the guide (www.NOACforAF.eu). It also contains links to the ESC AF Guidelines, a key message pocket booklet, print-ready files for a proposed universal NOAC anticoagulation card, and feedback possibilities.

  12. Management of malfunctioning and recalled pacemaker and defibrillator leads: results of the European Heart Rhythm Association survey.

    Science.gov (United States)

    Grazia Bongiorni, Maria; Dagres, Nikolaos; Estner, Heidi; Pison, Laurent; Todd, Derick; Blomstrom-Lundqvist, Carina

    2014-11-01

    The aim of this survey was to describe the different strategies regarding the management of malfunctioning and recalled pacemaker and defibrillator leads across Europe. A questionnaire has been designed to assess the current practice and physician's approach to the management of leads which are faulty, unnecessary, and/or recalled. Responses to the questionnaire were received from 34 hospitals-members of the European Heart Rhythm Association (EHRA) electrophysiology (EP) research network. The survey involved both very high and low volume implanting centres, with 85% of the responding centres performing lead extraction. The survey provides a panoramic view of operator's decision making in the field of malfunctioning, recalled, and redundant leads and outlines a common point of view on lead abandonment and factors influencing the decision about lead extraction. The main factors strongly influencing the decision making were patient's age (59%), the presence of the damaged leads (44%), and the lead dwelling time (44%). Regarding the lead abandonment, the main concern (61%) was the potential greater difficulty associated with lead extraction in the future. High volume extracting centres showed a greater propensity to removing the malfunctioning or recalled leads compared with low volume or non-extracting centres. This EP Wire survey gives a snapshot of the operators' approaches and options regarding redundant, malfunctioning, and recalled lead management and may form the basis for future prospective research on this topic. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  13. Approach to cardio-oncologic patients with special focus on patients with cardiac implantable electronic devices planned for radiotherapy: results of the European Heart Rhythm Association survey.

    Science.gov (United States)

    Lenarczyk, Radoslaw; Potpara, Tatjana S; Haugaa, Kristina H; Deharo, Jean-Claude; Hernandez-Madrid, Antonio; Del Carmen Exposito Pineda, Maria; Kiliszek, Marek; Dagres, Nikolaos

    2017-09-01

    The aim of this European Heart Rhythm Association (EHRA) survey was to evaluate clinical practice regarding cardio-oncologic patients, with special focus on patients with cardiac implantable electronic devices (CIEDs) planned for anticancer radiotherapy (RT), among members of the EHRA electrophysiology research network. Of the 36 responding centres, 89% managed patients who were diagnosed or treated oncologically, and this diagnosis affected 1-5% of cardiovascular patients in majority of centres (57%). The main side effects of anticancer therapy in patients treated by cardiologists were thromboembolic complications and left ventricular dysfunction (both reported as 'frequent' by 43% of the centres). The main agents associated with complications were anthracyclines, RT, and monoclonal antibodies. Echocardiography was the most common method of screening for cardiovascular complications (93%), and 10% of the centres did not routinely screen for treatment-induced cardiotoxicity. Opinions on the safe radiation dose, methods of device shielding, and risk calculation prior to RT in CIED patients differed among centres. Precaution measures in high-risk CIED patients were very heterogeneous among centres. Our survey has shown that the awareness of cardiac consequences of anticancer therapy is high, despite relatively low proportion of patients treated oncologically among all cardiovascular patients. There is a consensus of which screening methods should be used for cardiotoxicity of anticancer treatment, but the apprehension of screening necessity is low. Methods of risk assessment and safety measures in CIED patients undergoing RT are very heterogeneous among the European centres, underscoring the need for standardization of the approach to cardio-oncologic patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

  14. The European Heart Rhythm Association Practical Guide on the Use of New Oral Anticoagulants in Patients with Non-valvular Atrial Fibrillation – A Brief Summary

    Science.gov (United States)

    Kirchhof, Paulus

    2013-01-01

    New oral anticoagulants (NOACs) are an alternative to vitamin K antagonists (VKAs) in the prevention of stroke in patients with non-valvular atrial fibrillation (AF). The European Heart Rhythm Association (EHRA) has produced a practical guide to detail the use of NOACs in clinical practice. The guide includes a practical start-up and follow-up scheme, emphasising the importance of strict adherence to the regimen – the anticoagulant effect drops rapidly after 12–24 hours. There is also guidance on how to measure the anticoagulant effect of NOACs, switching between anticoagulant regimes and dealing with dosing errors. Physicians will have to consider the pharmacokinetic effect of drugs and co-morbidities when prescribing NOACs – plasma levels of NOACs may be affected by P-glycoprotein (P-gp) substrates, as well as cytochrome P450 (CYP3A4) inducers or inhibitors. In patients with chronic kidney disease, reduced doses of NOACs may be indicated. Guidance is also given on the management of bleeding complications, and the cessation and reinitiation of NOACs in patients undergoing surgical interventions. Finally, the use of NOACs in specific clinical situations is considered; these include patients with AF and coronary artery disease (CAD), patients presenting with acute stroke while taking NOACs and patients with cancer. PMID:26835051

  15. The European Heart Rhythm Association Practical Guide on the Use of New Oral Anticoagulants in Patients with Non-valvular Atrial Fibrillation - A Brief Summary.

    Science.gov (United States)

    Kirchhof, Paulus

    2013-11-01

    New oral anticoagulants (NOACs) are an alternative to vitamin K antagonists (VKAs) in the prevention of stroke in patients with non-valvular atrial fibrillation (AF). The European Heart Rhythm Association (EHRA) has produced a practical guide to detail the use of NOACs in clinical practice. The guide includes a practical start-up and follow-up scheme, emphasising the importance of strict adherence to the regimen - the anticoagulant effect drops rapidly after 12-24 hours. There is also guidance on how to measure the anticoagulant effect of NOACs, switching between anticoagulant regimes and dealing with dosing errors. Physicians will have to consider the pharmacokinetic effect of drugs and co-morbidities when prescribing NOACs - plasma levels of NOACs may be affected by P-glycoprotein (P-gp) substrates, as well as cytochrome P450 (CYP3A4) inducers or inhibitors. In patients with chronic kidney disease, reduced doses of NOACs may be indicated. Guidance is also given on the management of bleeding complications, and the cessation and reinitiation of NOACs in patients undergoing surgical interventions. Finally, the use of NOACs in specific clinical situations is considered; these include patients with AF and coronary artery disease (CAD), patients presenting with acute stroke while taking NOACs and patients with cancer.

  16. Access to and clinical use of cardiac implantable electronic devices and interventional electrophysiological procedures in the European Society of Cardiology Countries: 2016 Report from the European Heart Rhythm Association.

    Science.gov (United States)

    Raatikainen, M J Pekka; Arnar, David O; Merkely, Bela; Camm, A John; Hindricks, Gerhardt

    2016-08-01

    The aim of this analysis was to provide comprehensive information on the access to and use of cardiac implantable electronic device (CIED) and catheter ablation therapy in the European Society of Cardiology (ESC) area. The European Heart Rhythm Association (EHRA) has been collecting descriptive and quantitative data on invasive arrhythmia therapies since 2008. This year 50 of the 56 ESC member countries provided data for the EHRA White Book. Up-to-date information on procedure rates for the last 5 years together with information on demographics, economy, vital statistics, local healthcare systems, and training activities is presented for each country and the 5 geographical ESC regions. Our analysis indicated that considerable heterogeneity in the access to arrhythmia therapies still exists across the ESC area. In 2015, the CIED implantation rates per million population were highest in the Western followed by the Southern and Northern European countries. The catheter ablation activity was largest in the Western followed by the Northern and Southern areas. Overall, the procedure rates were 3-10 times higher in the European than in the non-European ESC countries. Economic resources were not the only driver for utilization of arrhythmia therapies as in some Eastern European countries with relative low gross domestic product the procedure rates exceeded the average values. These data will help the healthcare professionals and stakeholders to identify and to understand in more depth the trends, disparities, and gaps in cardiac arrhythmia care and thereby promote harmonization of cardiac arrhythmias therapies in the ESC area. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  17. Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation.

    Science.gov (United States)

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Diener, Hans-Christoph; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2015-10-01

    The current manuscript is an update of the original Practical Guide, published in June 2013[Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-51; Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, et al. EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary. Eur Heart J 2013;34:2094-106]. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients have to learn how to use these drugs effectively and safely in clinical practice. Many unresolved questions on how to optimally use these drugs in specific clinical situations remain. The European Heart Rhythm Association set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group defined what needs to be considered as 'non-valvular AF' and listed 15 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 15 topics are (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring adherence of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (xi) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease

  18. Biological rhythms are independently associated with quality of life in bipolar disorder.

    Science.gov (United States)

    Cudney, Lauren E; Frey, Benicio N; Streiner, David L; Minuzzi, Luciano; Sassi, Roberto B

    2016-12-01

    Evidence suggests that patients with bipolar disorder (BD) experience biological rhythm disturbances; however, no studies have examined the impact of this disruption on quality of life (QOL). The aim of this study is to investigate the influence of biological rhythm, depressive symptoms, sleep quality, and sleep medication use on QOL in BD. Eighty BD subjects (44 depressed and 36 euthymic) completed questionnaires assessing QOL (WHOQOL-BREF), biological rhythm disruption (BRIAN), depressive symptoms (MADRS), and sleep quality (PSQI). The impact of biological rhythm disturbance, depressive symptoms severity, sleep quality, and sleep medication use on QOL was determined with multiple regression analyses. BRIAN (β = -0.31, t = -2.73, p biological rhythm disturbance (β = -0.43, t = -3.66, p rhythm theory of BD. Physical QOL was associated with depression (β = -0.30, t = -2.93, p biological rhythm disruption (β = -0.31, t = -2.73, p biological rhythms in relation to QOL. Disruption in biological rhythm is associated with poor QOL in BD, independent of sleep disturbance, sleep medication use, and severity of depression. Treatment strategies targeting regulation of biological rhythms, such as sleep/wake cycles, eating patterns, activities, and social rhythms, are likely to improve QOL in this population.

  19. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation.

    Science.gov (United States)

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2013-05-01

    New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in clinical practice. Many unresolved questions on how to optimally use these drugs in specific clinical situations remain. The European Heart Rhythm Association set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group listed 15 topics of concrete clinical scenarios and formulated as practical answers as possible based on available evidence. The 15 topics are: (1) Practical start-up and follow-up scheme for patients on NOACs; (2) How to measure the anticoagulant effect of NOACs; (3) Drug-drug interactions and pharmacokinetics of NOACs; (4) Switching between anticoagulant regimens; (5) Ensuring compliance of NOAC intake; (6) How to deal with dosing errors; (7) Patients with chronic kidney disease; (8) What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding? (9) Management of bleeding complications; (10) Patients undergoing a planned surgical intervention or ablation; (11) Patients undergoing an urgent surgical intervention; (12) Patients with AF and coronary artery disease; (13) Cardioversion in a NOAC-treated patient; (14) Patients presenting with acute stroke while on NOACs; (15) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA Web site with the latest updated information accompanies this text (www.NOACforAF.eu).

  20. A Large Right Atrial Myxoma Associated with Atrial Flutter Rhythm

    Directory of Open Access Journals (Sweden)

    Onursal Buğra

    2010-04-01

    Full Text Available A 22 year-old man presented to the emergency unit with the complaint of difficulty in breathing. In the physical exam, dyspnea and orthopnea were found. In the electocardiographic exam (ECG atrial flutter rhythm was seen. The transthoracic echocardiographic exam revealed a large atrial mass that was originating from interatrial septum. During surgery, complete surgical removal of the right atrial mass was successfully performed under moderate hypothermia. Histological investigations revealed a mass of 15 x 3 cm in diameter and the pathological examination showed that the lesion is a myxoma. Twelve months after surgical excision, clinical and chocardiographicalfollow-up showed a satisfactory exercise tolerance, sinus rhythm in ECG exam, and cardiac functions within normal limits.

  1. Hypertension and cardiac arrhythmias : A consensus document fromthe European Heart RhythmAssociation (EHRA) and ESC Council on Hypertension, endorsed by the Heart RhythmSociety (HRS), Asia-Pacific Heart RhythmSociety (APHRS) and Sociedad Latinoamericana de Estimulacion Cardiaca y Electrofisiologia (SOLEACE)

    NARCIS (Netherlands)

    Lip, Gregory Y. H.; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S.; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S.; Steffel, Jan; Marin, Francisco; de Oliveira Figueiredo, Marcio Jansen; de Simone, Giovanni; Tzou, Wendy S.; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

    2017-01-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both

  2. Tide-associated biological rhythms of some white sea littoral invertebrates.

    Science.gov (United States)

    Gusev, O. A.; Golubev, A. I.

    2001-01-01

    We report the results from two years of laboratory observations of the tide-associated rhythms of activity of White Sea intertidal invertebrates, Mya arenaria (Bivalvia) and Gammarus finmarchicus (Amphipoda). The tidal associated activity of these invertebrates could not be estimate as a clear circatidal clock. Gammarus activity could be phase shifted by a 0.5 h exposure to turbulent water twice a day for 2-3 days. Mya's rhythm could be changed by a single drainage of aquariums lasting about 15 min. This kind of timing system may be a relatively primitive evolution feature.

  3. Heart rhythm disturbances associated with rupatadine: a case series from the Spanish and Portuguese pharmacovigilance systems.

    Science.gov (United States)

    Carvajal, A; Macías, D; Salado, I; Sáinz, M; Ortega, S; Campo, C; García del Pozo, J; Martín Arias, L H; Velasco, A; Gonçalves, S; Pombal, R; Carmona, R

    2009-05-01

    We searched the Spanish and Portuguese pharmacovigilance databases for spontaneous case reports of heart rhythm disturbances associated with rupatadine and other new H1 antihistamines. Five cases were found involving patients treated with rupatadine (13.9% of all reports relating to this drug). In all five cases, the reaction started after exposure and resolved when the drug was discontinued. In two cases, rupatadine was the only medication being taken by the patient, and no other condition that could explain the heart rhythm disturbances was diagnosed. The reporting odds ratio was 3.2 (95% confidence interval, 1.0-10.5). The reporting rate was 2 cases per 100,000 patients treated per year (95% confidence interval, 0.4-6.0). These results suggest a causal relationship between rupatadine and heart rhythm disturbances.

  4. EHRA: Specification and Analysis of Energy-Harvesting Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Dung, Phan Anh; Hansen, Michael Reichhardt; Madsen, Jan

    2014-01-01

    to study wireless sensor networks (WSN) with energy-harvesting capabilities. The purpose of the framework is to analyze WSNs at a high level of abstraction, that is, before the protocols are implemented and before the WSN is deployed. The conceptual basis of EHRA comprises the environment, the medium...... is developed as a simulator implemented using the functional programming language F#. This simulator is used to analyze global properties of WSNs such as network fragmentation,routing trends, and energy profiles for the nodes. Three routing protocols, with a progression in the energy-harvesting awareness......, are analyzed on a network that is placed in a heterogeneous environment....

  5. Heart rhythm risturbances associated with rupatadine: a case series from the Spanish and Portuguese Pharmacovigilance Systems

    OpenAIRE

    Carvajal García-Pando, Alfonso; Macías, D.; Salado, Inés; Sáinz, M.; Ortega, Sara; Campo, C.; García del Pozo, Javier; Martín Arias, Luis; Velasco Martín, Alfonso; R Gonçalves; Pombal, R.; Carmona, R

    2009-01-01

    Producción Científica We searched the Spanish and Portuguese pharmacovigilance databases for spontaneous case reports of heart rhythm disturbances associated with rupatadine and other new H1 antihistamines. Five cases were found involving patients treated with rupatadine (13.9% of all reports relating to this drug). In all five cases, the reaction started after exposure and resolved when the drug was discontinued. In two cases, rupatadine was the only medication being taken by the patient,...

  6. Association of circadian rhythm genes ARNTL/BMAL1 and CLOCK with multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Polona Lavtar

    Full Text Available Prevalence of multiple sclerosis varies with geographic latitude. We hypothesized that this fact might be partially associated with the influence of latitude on circadian rhythm and consequently that genetic variability of key circadian rhythm regulators, ARNTL and CLOCK genes, might contribute to the risk for multiple sclerosis. Our aim was to analyse selected polymorphisms of ARNTL and CLOCK, and their association with multiple sclerosis. A total of 900 Caucasian patients and 1024 healthy controls were compared for genetic signature at 8 SNPs, 4 for each of both genes. We found a statistically significant difference in genotype (ARNTL rs3789327, P = 7.5·10-5; CLOCK rs6811520 P = 0.02 distributions in patients and controls. The ARNTL rs3789327 CC genotype was associated with higher risk for multiple sclerosis at an OR of 1.67 (95% CI 1.35-2.07, P = 0.0001 and the CLOCK rs6811520 genotype CC at an OR of 1.40 (95% CI 1.13-1.73, P = 0.002. The results of this study suggest that genetic variability in the ARNTL and CLOCK genes might be associated with risk for multiple sclerosis.

  7. Cryoablation for treatment of cardiac arrhythmias: results of the European Heart Rhythm Association survey.

    Science.gov (United States)

    Chen, Jian; Lenarczyk, Radoslaw; Boveda, Serge; Richard Tilz, Roland; Hernandez-Madrid, Antonio; Ptaszynski, Pawel; Pudulis, Janis; Dagres, Nikolaos

    2017-02-01

    The purpose of this survey was to assess the current practice in Europe regarding cryoablation for treatment of different cardiac arrhythmias. The data are based on an electronic questionnaire sent to members of the European Heart Rhythm Association Research Network. Responses were received from 49 centres in 18 countries. The results show that cryoablation for supraventricular tachycardia in European centres is an alternative to radiofrequency ablation, which is in accordance with guidelines. There is reasonable consensus regarding clinical results and complications of cryoablation procedure. Some inter-centre variability with respect to patient selection and ablation strategy in cryoablation of atrial fibrillation was demonstrated, underscoring the need for further research.

  8. A marked decrease in heart rate variability associated with junctional rhythm during anesthesia with sevoflurane and fentanyl.

    Science.gov (United States)

    Fujiwara, Y; Asakura, Y; Shibata, Y; Nishiwaki, K; Komatsu, T

    2006-04-01

    Heart rate variability (HRV) was investigated using a new technique for time series analysis combining the maximum entropy method and non-linear least squares method -- the 'MemCalc method' -- in patients undergoing general anesthesia with sevoflurane and fentanyl for elective surgery. As the occurrence of junctional rhythm coincided with the measurement of these variables in two patients, we successfully evaluated the entropy, low (LF) and high (HF) frequency component of the HRV during junctional rhythm and found that the occurrence of junctional rhythm is associated with marked decreases in the entropy, LF and HF of HRV. When evaluating autonomic control of the heart using HRV analysis, the decrease in HRV caused by the occurrence of junctional rhythm must be taken into account.

  9. Evaluating the associations between human circadian rhythms and dysregulated genes in liver cancer cells.

    Science.gov (United States)

    Polo, Andrea; Singh, Sakshi; Crispo, Anna; Russo, Marilina; Giudice, Aldo; Montella, Maurizio; Colonna, Giovanni; Costantini, Susan

    2017-12-01

    Network analysis is a useful approach in cancer biology as it provides information regarding the genes and proteins. In our previous study, a network analysis was performed on dysregulated genes in HepG2 cells, a hepatoblastoma cell line that lacks the viral infection, compared with normal hepatocytes, identifying the presence of 26 HUB genes. The present study aimed to identify whether these previously identified HUB genes participate in the network that controls the human circadian rhythms. The results of the present study demonstrated that 20/26 HUB genes were associated with the metabolic processes that control human circadian rhythms, which supports the hypothesis that a number of cancer types are dependent from circadian cycles. In addition, it was revealed that the CLOCK circadian regulator gene was associated, via cytoskeleton associated protein 5 (CKAP5), with the HUB genes of the HepG2 network, and that CKAP5 was associated with three other circadian genes (casein kinase 1ε, casein kinase 1δ and histone deacetylase 4) and 10 HepG2 genes (SH2 domain containing, ZW10 interacting kinetochore protein, aurora kinase B, cell division cycle 20, centromere protein A, inner centromere protein, mitotic arrest deficient 2 like 1, baculoviral IAP repeat containing 5, SPC24 NDC80 kinetochore complex component and kinesin family member 2C). Furthermore, the genes that associate the circadian system with liver cancer were demonstrated to encode intrinsically disordered proteins. Finally, the results of the present study identified the microRNAs involved in the network formed by the overlapping of HepG2 and circadian genes.

  10. Differences in daily rhythms of wrist temperature between obese and normal-weight women: associations with metabolic syndrome features

    Science.gov (United States)

    The circadian rhythm of core body temperature is associated with widespread physiological effects. However, studies with other more practical temperature measures, such as wrist (WT) and proximal temperatures, are still scarce. The aim of this study was to investigate whether obesity is associated w...

  11. Mild Depressive Symptoms During the Third Trimester of Pregnancy Are Associated with Disruptions in Daily Rhythms but Not Subjective Sleep Quality.

    Science.gov (United States)

    Simpson, William; Frey, Benicio N; Steiner, Meir

    2016-06-01

    Recent research in major depressive disorder suggests that dysregulation of the circadian system may be a core pathophysiological component. In pregnancy, women often experience significant disruptions in their daily rhythms, including changes in day-to-day schedule and sleep habits. Current evidence suggests that these disruptions in daily rhythms may adversely affect underlying circadian rhythmicity. The purpose of our study was to examine whether subjectively rated daily rhythm disruptions were associated with a greater incidence of depressive symptoms during the third trimester. Our study was a cross-sectional design, assessing sleep quality, symptoms of depression, and daily rhythm disruptions in 51 pregnant women in their third trimester. We observed a significant relationship between mild depressive symptoms and disruptions in daily rhythms. While we initially observed a strong correlation between subjective sleep quality and depressive symptoms, this was attenuated after accounting for daily rhythm disruptions. Disruptions in daily social rhythms, eating patterns, and general activity were all significantly associated with depressive symptomatology. Our findings point to a strong correlation between daily rhythm disruptions and prenatal depressive symptoms. Given that these daily rhythms are known to act as zeitgebers, longitudinal studies examining the directionality of this relationship between circadian rhythms and depressive symptoms during pregnancy are warranted.

  12. Is low docosahexaenoic acid associated with disturbed rhythms and neurodevelopment in offsprings of diabetic mothers?

    Science.gov (United States)

    Zornoza-Moreno, M; Fuentes-Hernández, S; Carrión, V; Alcántara-López, M V; Madrid, J A; López-Soler, C; Sánchez-Solís, M; Larqué, E

    2014-08-01

    To evaluate the relation between docosahexaenoic acid (DHA) status and neurodevelopment in the offsprings of gestational diabetic mothers (ODMs). A prospective cohort study was performed. The offspring of 63 pregnant women (23 controls, 21 diet-controlled gestational diabetes mellitus (GDM) and 19 insulin-treated GDM) were recruited. Maternal and venous cord plasma DHA percentages were analyzed. Skin temperature and activity in children were recorded for 72 h at 3 and 6 months of life. Neurodevelopment was assessed using the Bayley Scale of Infant Development II (BSID II) at 6 and 12 months of age. Cord plasma DHA percentage was significantly lower in the ODMs compared with that in the controls (Control 6.43 [5.04-7.82](a); GDM+diet 5.65 [4.44-6.86](ab); GDM+insulin 5.53 [4.45-6.61](b)). Both mental (Control 102.71 [97.61-107.81](a); GDM+diet 100.39 [91.43-109.35](a); GDM+insulin 93.94 [88.31-99.57](b)) and psychomotor (Control 91.52 [81.82-101.22](a); GDM+diet 81.67 [73.95-89.39](b); GDM+insulin 81.89 [71.96-91.85](b)) scores evaluated by the BSID II were significantly lower at 6 months in ODMs, even after adjusting for confounding factors such as breastfeeding, maternal educational level and gender. Cord plasma DHA percentage correlated with the psychomotor score from BSID II (r=0.27; P=0.049) and with the intra-daily variability in activity (r=-0.24; P=0.043) at 6 months. Maternal DHA was correlated with several sleep rhythm maturation parameters at 6 months. Lower DHA levels in cord plasma of ODMs could affect their neurodevelopment. Maternal DHA status was also associated with higher values in the sleep rhythm maturation parameters of children.

  13. Mu rhythm suppression is associated with the classification of emotion in faces.

    Science.gov (United States)

    Moore, Matthew R; Franz, Elizabeth A

    2017-02-01

    The mirror neuron system (MNS) has been mooted as a crucial component underlying human social cognition. Initial evidence based on functional magnetic resonance imaging (fMRI) suggests that the MNS plays a role in emotion classification, but further confirmation and convergent evidence is needed. This study employed electroencephalography (EEG) to examine modulations in the mu rhythm associated with the inference of emotions from facial expressions. It was hypothesised that mu suppression would be associated with classifying the emotion portrayed by facial expressions. Nineteen participants viewed pictures of facial expressions or emotion words and were asked to either match the stimulus to an emotion word or to passively observe. Mu activity following stimulus presentation was localised using a 3-D distributed inverse solution, and compared between conditions. Subtractive logic was used to isolate the specific processes of interest. Comparisons of source localisation images between conditions revealed that there was mu suppression associated with recognising emotion from faces, thereby supporting our hypothesis. Further analyses confirmed that those effects were not due to activity associated with the motor response or the observation of facial expressions, offering further support for the hypotheses. This study provides important convergent evidence for the involvement of the MNS in the inference of emotion from facial expressions.

  14. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    range of animals. The study of circadian rhythms in animals revealed that individu- als display multiple rhythms. For example, mammals exhibit rhythms in locomotor activity, drinking, body temperature, blood sugar, liver glycogen, eosinophil count, adrenal activity, pineal melatonin and corticosteroid levels and sensitivity to ...

  15. Painted Rhythms.

    Science.gov (United States)

    Bastian, Duane

    1985-01-01

    In this art activity gifted students, ages 10 to 13, learn about internal and external rhythms and make a painting of an internal rhythm. The lesson can be expanded with a discussion of Kandinsky, Pollock, and other painters who have painted sound or have demonstrated rhythms. (RM)

  16. [REGULATING EFFECT OF ASSOCIATIVE MICROBIOTA ON THE RHYTHMS OF BIOLOGICAL PROPERTIES OF FUNGI AND BACTERIA].

    Science.gov (United States)

    Timokhina, T Kh; Bukharin, O V; Nikolenko, M V; Paromova, Ya I; Perunova, N B

    2015-01-01

    Study the effect of exometabolites of associative microbiota on circadian dynamics of functional parameters, that reflect pathogenic and persistence properties of fungi and bacteria. Clinical isolates of Candida albicans, isolated-from intestine of healthy individuals and patients with candidosis, as well as clinical isolates and museum ATCC strains Staphylococcus. aureus 25923, Escherichia coli 35218 and Pseudomonas aeruginosa 27853 were taken for study of proliferative, adhesive, catalase, protease, phospholipase, hemolytic, anti-lysozyme, biofilm-forming activity. The results were treated statistically. C. albicans isolates, isolated from healthy individuals were revealed to be indifferent to the effect of bacterial metabolites. Chrono-infrastructure of biological properties of fungi altered under the effect of microbiota metabolites. Hospital isolates of S. aureus, E. coli and P. aeruginosa displayed a relative stability of physiological properties against the effect of bacterial-fungal metabolites as opposed to museum strains. The alterations of chrono-infrastructure of biological rhythms of microorganisms by bacterial-fungal metabolites of associants reflect the intensity of the biological system, that is inevitable during the process of formation of inter-microbial interactions.

  17. Inter-Individual Differences in Neurobehavioural Impairment following Sleep Restriction Are Associated with Circadian Rhythm Phase

    Science.gov (United States)

    Sletten, Tracey L.; Segal, Ahuva Y.; Flynn-Evans, Erin E.; Lockley, Steven W.; Rajaratnam, Shantha M. W.

    2015-01-01

    Although sleep restriction is associated with decrements in daytime alertness and neurobehavioural performance, there are considerable inter-individual differences in the degree of impairment. This study examined the effects of short-term sleep restriction on neurobehavioural performance and sleepiness, and the associations between individual differences in impairments and circadian rhythm phase. Healthy adults (n = 43; 22 M) aged 22.5 ± 3.1 (mean ± SD) years maintained a regular 8:16 h sleep:wake routine for at least three weeks prior to laboratory admission. Sleep opportunity was restricted to 5 hours time-in-bed at home the night before admission and 3 hours time-in-bed in the laboratory, aligned by wake time. Hourly saliva samples were collected from 5.5 h before until 5 h after the pre-laboratory scheduled bedtime to assess dim light melatonin onset (DLMO) as a marker of circadian phase. Participants completed a 10-min auditory Psychomotor Vigilance Task (PVT), the Karolinska Sleepiness Scale (KSS) and had slow eye movements (SEM) measured by electrooculography two hours after waking. We observed substantial inter-individual variability in neurobehavioural performance, particularly in the number of PVT lapses. Increased PVT lapses (r = -0.468, p sleep restriction, and confirms that other factors influencing performance decrements require further investigation. PMID:26043207

  18. Foreign language learning in French speakers is associated with rhythm perception, but not with melody perception.

    Science.gov (United States)

    Bhatara, Anjali; Yeung, H Henny; Nazzi, Thierry

    2015-04-01

    There has been increasing interest in links between language and music. Here, we investigate the relation between foreign language learning and music perception. We administered tests measuring melody and rhythm perception as well as a questionnaire on musical and foreign language experience to 147 monolingual French speakers. As expected, we found that musicians had better melody and rhythm perception than nonmusicians and that, among musicians, there was a positive correlation between the total number of years of music training and test scores. Crucially, we also found a positive correlation between the total number of years learning foreign languages and rhythm perception, but we found no such relation with melody perception. Moreover, the degree to which participants were better at rhythm than melody perception was also related to foreign language experience. Results suggest that both music training and learning foreign languages (primarily English, Spanish, and German in our sample) are related to French speakers' perception of rhythm, but not to their perception of melody. These results are discussed with respect to the rhythmic properties of French and suggest a common perceptual basis for rhythm in language and music. (c) 2015 APA, all rights reserved.

  19. Comparison of Left Atrial Voltage between Sinus Rhythm and Atrial Fibrillation in Association with Electrogram Waveform.

    Science.gov (United States)

    Masuda, Masaharu; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Sunaga, Akihiro; Tsujimura, Takuya; Matsuda, Yasuhiro; Ohashi, Takuya; Uematsu, Masaaki

    2017-05-01

    The efficacy of low-voltage-guided ablation in addition to pulmonary vein (PV) isolation for atrial fibrillation (AF) has been reported with voltage mapping being performed during sinus rhythm (SR) or AF. The study aimed to compare the left atrial voltage between SR and AF in association with the electrogram waveform. This prospective observational study included 30 consecutive patients with persistent AF. After completion of PV isolation, electrogram points were taken during both SR and AF at the identical locations evenly throughout the left atrium. Electrograms were divided into two types: normal (sharp electrogram with ≤3 peaks or duration 3 peaks and duration ≥50 ms). During SR, 14 (47%) patients had low-voltage (0.5 mV) substrate with an area of 6.8 ± 4.5 cm 2 . In a total of 1,063 point pairs, 135 (13%) demonstrated a fractionated electrogram during SR and 483 (45%) during AF. The locations with fractionated electrograms during AF more frequently showed fractionation during SR compared to those with normal electrograms during AF (23% vs 5%, P voltage and fractionation degree may exist between SR and AF at the same locations in patients with persistent AF. © 2017 Wiley Periodicals, Inc.

  20. Inter-Individual Differences in Neurobehavioural Impairment following Sleep Restriction Are Associated with Circadian Rhythm Phase.

    Directory of Open Access Journals (Sweden)

    Tracey L Sletten

    Full Text Available Although sleep restriction is associated with decrements in daytime alertness and neurobehavioural performance, there are considerable inter-individual differences in the degree of impairment. This study examined the effects of short-term sleep restriction on neurobehavioural performance and sleepiness, and the associations between individual differences in impairments and circadian rhythm phase. Healthy adults (n = 43; 22 M aged 22.5 ± 3.1 (mean ± SD years maintained a regular 8:16 h sleep:wake routine for at least three weeks prior to laboratory admission. Sleep opportunity was restricted to 5 hours time-in-bed at home the night before admission and 3 hours time-in-bed in the laboratory, aligned by wake time. Hourly saliva samples were collected from 5.5 h before until 5 h after the pre-laboratory scheduled bedtime to assess dim light melatonin onset (DLMO as a marker of circadian phase. Participants completed a 10-min auditory Psychomotor Vigilance Task (PVT, the Karolinska Sleepiness Scale (KSS and had slow eye movements (SEM measured by electrooculography two hours after waking. We observed substantial inter-individual variability in neurobehavioural performance, particularly in the number of PVT lapses. Increased PVT lapses (r = -0.468, p < 0.01, greater sleepiness (r = 0.510, p < 0.0001, and more slow eye movements (r = 0.375, p = 0.022 were significantly associated with later DLMO, consistent with participants waking at an earlier circadian phase. When the difference between DLMO and sleep onset was less than 2 hours, individuals were significantly more likely to have at least three attentional lapses the following morning. This study demonstrates that the phase of an individual's circadian system is an important variable in predicting the degree of neurobehavioural performance impairment in the hours after waking following sleep restriction, and confirms that other factors influencing performance decrements require further

  1. A review of human physiological and performance changes associated with desynchronosis of biological rhythms

    Science.gov (United States)

    Winget, C. M.; Deroshia, C. W.; Markley, C. L.; Holley, D. C.

    1984-01-01

    This review discusses the effects, in the aerospace environment, of alterations in approximately 24-h periodicities (circadian rhythms) upon physiological and psychological functions and possible therapies for desynchronosis induced by such alterations. The consequences of circadian rhythm alteration resulting from shift work, transmeridian flight, or altered day lengths are known as desynchronosis, dysrhythmia, dyschrony, jet lag, or jet syndrome. Considerable attention is focused on the ability to operate jet aircraft and manned space vehicles. The importance of environmental cues, such as light-dark cycles, which influence physiological and psychological rhythms is discussed. A section on mathematical models is presented to enable selection and verification of appropriate preventive and corrective measures and to better understand the problem of dysrhythmia.

  2. Heart rate is associated with progression of atrial fibrillation, independent of rhythm.

    Science.gov (United States)

    Holmqvist, Fredrik; Kim, Sunghee; Steinberg, Benjamin A; Reiffel, James A; Mahaffey, Kenneth W; Gersh, Bernard J; Fonarow, Gregg C; Naccarelli, Gerald V; Chang, Paul; Freeman, James V; Kowey, Peter R; Thomas, Laine; Peterson, Eric D; Piccini, Jonathan P

    2015-06-01

    Atrial fibrillation (AF) often progresses from paroxysmal or persistent to more sustained forms, but the rate and predictors of AF progression in clinical practice are not well described. Using the Outcomes Registry for Better Informed Treatment of AF, we analysed the incidence and predictors of progression and tested the discrimination and calibration of the HATCH (hypertension, age, TIA/stroke, chronic obstructive pulmonary disease, heart failure) and CHA₂DS₂VASc scores for identifying AF progression. Among 6235 patients with paroxysmal or persistent AF at baseline, 1479 progressed, during follow-up (median 18 (IQR 12-24) months). These patients were older and had more comorbidities than patients who did not progress (CHADS₂ 2.3±1.3 vs 2.1±1.3, prate control as opposed to a rhythm control strategy (66 vs 56%, pheart rate (72(64-80) vs 68(60-76) bpm, pheart rate (OR 0.84, 95% CI 0.79 to 0.89, pheart rate (p=0.71). The HATCH and CHA₂DS₂VASc scores had modest discriminatory power for AF progression (C-indices 0.55 (95% CI 0.53 to 0.58) and 0.55 (95% CI 0.52 to 0.57)). Within 1.5 years, almost a quarter of the patients with paroxysmal or persistent AF progress to a more sustained form. Progression is strongly associated with heart rate, and age. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  3. Rest-activity rhythm and sleep characteristics associated with depression symptom severity in strained dementia caregivers.

    Science.gov (United States)

    Smagula, Stephen F; Krafty, Robert T; Taylor, Briana J; Martire, Lynn M; Schulz, Richard; Hall, Martica H

    2017-12-01

    Depression is associated with disturbances to sleep and the 24-h sleep-wake pattern (known as the rest-activity rhythm: RAR). However, there remains a need to identify the specific sleep/RAR correlates of depression symptom severity in population subgroups, such as strained dementia caregivers, who are at elevated risk for major depressive disorder. We assessed the cross-sectional associations of sleep/RARs with non-sleep depression symptom severity among 57 (mean age: 74 years, standard deviation: 7.4) strained dementia caregivers who were currently without clinical depression. We derived sleep measures from polysomnography and actigraphy, modelled RARs using a sigmoidally transformed cosine curve and measured non-sleep depression symptom severity using the Hamilton Depression Rating Scale (HRDS) with sleep items removed. The following sleep-wake measures were associated with greater depression symptom severity (absolute Spearman's correlations ranged from 0.23 to 0.32): more time awake after sleep onset (WASO), higher RAR middle level (mesor), relatively shorter active periods (alpha), earlier evening settling time (down-mesor) and less steep RARs (beta). In multivariable analysis, high WASO and low RAR beta were associated independently with depression symptom severity. Predicted non-sleep HDRS means (95% confidence intervals) in caregivers with and without these characteristics were: normal WASO/beta = 3.7 (2.3-5.0), high WASO/normal beta = 5.5 (3.5-7.6), normal WASO/low beta = 6.3 (3.6-8.9) and high WASO/low beta = 8.1 (5.3-10.9). Thus, in our sample of strained caregivers, greater sleep fragmentation (WASO) and less sustained/sharply segregated resting and active periods (low RAR beta) correlate uniquely with depression symptom severity. Longitudinal studies are needed to establish whether these independent sleep-wake correlates of depression symptoms explain heightened depression risk in dementia caregivers. © 2017 European Sleep Research Society.

  4. Automatic evaluation of speech rhythm instability and acceleration in dysarthrias associated with basal ganglia dysfunction

    Directory of Open Access Journals (Sweden)

    Jan eRusz

    2015-07-01

    Full Text Available Speech rhythm abnormalities are commonly present in patients with different neurodegenerative disorders. These alterations are hypothesized to be a consequence of disruption to the basal ganglia circuitry involving dysfunction of motor planning, programming and execution, which can be detected by a syllable repetition paradigm. Therefore, the aim of the present study was to design a robust signal processing technique that allows the automatic detection of spectrally-distinctive nuclei of syllable vocalizations and to determine speech features that represent rhythm instability and acceleration. A further aim was to elucidate specific patterns of dysrhythmia across various neurodegenerative disorders that share disruption of basal ganglia function. Speech samples based on repetition of the syllable /pa/ at a self-determined steady pace were acquired from 109 subjects, including 22 with Parkinson's disease (PD, 11 progressive supranuclear palsy (PSP, 9 multiple system atrophy (MSA, 24 ephedrone-induced parkinsonism (EP, 20 Huntington's disease (HD, and 23 healthy controls. Subsequently, an algorithm for the automatic detection of syllables as well as features representing rhythm instability and rhythm acceleration were designed. The proposed detection algorithm was able to correctly identify syllables and remove erroneous detections due to excessive inspiration and nonspeech sounds with a very high accuracy of 99.6%. Instability of vocal pace performance was observed in PSP, MSA, EP and HD groups. Significantly increased pace acceleration was observed only in the PD group. Although not significant, a tendency for pace acceleration was observed also in the PSP and MSA groups. Our findings underline the crucial role of the basal ganglia in the execution and maintenance of automatic speech motor sequences. We envisage the current approach to become the first step towards the development of acoustic technologies allowing automated assessment of rhythm

  5. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 11. Circadian Rhythms - Circadian Timing Systems: How are they Organized? Koustubh M Vaze Vijay Kumar Sharma. Series Article Volume 18 Issue 11 November 2013 pp 1032-1050 ...

  6. Health impact of fasting in Saudi Arabia during Ramadan: association with disturbed circadian rhythm and metabolic and sleeping patterns.

    Science.gov (United States)

    Ajabnoor, Ghada M; Bahijri, Suhad; Borai, Anwar; Abdulkhaliq, Altaf A; Al-Aama, Jumana Y; Chrousos, George P

    2014-01-01

    Muslims go through strict Ramadan fasting from dawn till sunset for one month yearly. These practices are associated with disturbed feeding and sleep patterns. We recently demonstrated that, during Ramadan, circadian cortisol rhythm of Saudis is abolished, exposing these subjects to continuously increased cortisol levels. Secretory patterns of other hormones and metabolic parameters associated with cortisol, and insulin resistance, might be affected during Ramadan. Ramadan practitioners (18 males, 5 females; mean age ±SEM = 23.16±1.2 years) were evaluated before and two weeks into Ramadan. Blood was collected for measurements of endocrine and metabolic parameters at 9 am (±1 hour) and again twelve hours later. In Ramadan, glucose concentration was kept within normal range, with a significant increase in the morning. Mean morning concentration of leptin was significantly higher than pre-Ramadan values (p = 0.001), in contrast to that of adiponectin, which was significantly lower (pRamadan than those during regular living conditions, however, normal circadian fluctuation was abolished (p = 0.49). Even though means of liver enzymes, total bilirubin, total protein and albumin were all decreased during Ramadan, statistically lower means were only noted for GGT, total protein, and albumin (p = 0.018, 0.002 and 0.001 respectively). Saudi Ramadan practitioners have altered adipokine patterns, typical of insulin resistance. The noted decreases of hsCRP, liver enzymes, total protein, and albumin, are most likely a result of fasting, while loss of circadian rhythmicity of hsCRP is probably due to loss of circadian cortisol rhythm. Modern Ramadan practices in Saudi Arabia, which are associated with evening hypercortisolism, are also characterized by altered adipokines patterns, and an abolished hsCRP circadian rhythm, all likely to increase cardiometabolic risk.

  7. Atrial fibrillation is associated with decreased cardiac sympathetic response to isometric exercise in CHF in comparison to sinus rhythm.

    Science.gov (United States)

    Gould, Paul A; Esler, Murray D; Kaye, David M

    2008-09-01

    The presence of atrial fibrillation (AF) in congestive heart failure (CHF) is accompanied by increased mortality, although the exact mechanism is unclear. In previous studies, we have demonstrated cardiac baroreceptor abnormalities in association with AF and CHF. In this study, we sought to examine the effect of cardiac rhythm on the cardiac sympathetic response to exercise in CHF. In 13 CHF patients (six AF, seven SR, left ventricular ejection fraction 31 +/- 2%, age 61 +/- 1 years), we measured the hemodynamic and cardiac sympathetic response isometric handgrip (IHG) exercise. At baseline the groups were well matched. Baseline hemodynamics and cardiac sympathetic activity did not significantly differ between the cohorts. In response to IHG exercise, both groups demonstrated significant hemodynamic responses. In conjunction, the sinus rhythm (SR) group demonstrated a significant increase in cardiac sympathetic response to exercise (P = 0.04) while in contrast the AF group did not (P = 0.6). In this study, we demonstrate for the first time that the combination of AF and CHF is accompanied by a marked attenuation of the cardiac sympathetic response to acute hemodynamic stress. This implies AF is associated with a further impairment of baroreceptor response in CHF compared to SR. These findings present possible insights to the associated increased mortality and pathogenesis of AF with CHF.

  8. [Affective disorders and biological rhythms].

    Science.gov (United States)

    Le Strat, Y; Ramoz, N; Gorwood, P

    2008-06-01

    Disruptions of circadian rhythms are described in affective disorders, including unipolar and bipolar disorder, but also seasonal affective disorder. Sleep-wake and hormone circadian rhythms are among the most quoted examples. Depression could be conceptualized as a desynchronization between the endogenous circadian pacemaker and the exogenous stimuli, such as sunlight and social rhythms. Accordingly, Clock genes have been studied and the literature suggests that variants in these genes confer a higher risk of relapse, more sleep disturbances associated with depression, as well as incomplete treatment response. Most of therapeutic interventions in depression have an impact on biological rhythms. Some of them exclusively act via a biological pathway, such as sleep deprivation or light therapy. Some psychosocial interventions are specifically focusing on social rhythms, particularly in bipolar disorder, in which the promotion of stabilization is emphasized. Finally, all antidepressant medications could improve biological rhythms, but some new agents are now totally focusing this novel approach for the treatment of depression.

  9. Biological rhythms

    Science.gov (United States)

    Halberg, F.

    1975-01-01

    An overview is given of basic features of biological rhythms. The classification of periodic behavior of physical and psychological characteristics as circadian, circannual, diurnal, and ultradian is discussed, and the notion of relativistic time as it applies in biology is examined. Special attention is given to circadian rhythms which are dependent on the adrenocortical cycle. The need for adequate understanding of circadian variations in the basic physiological indicators of an individual (heart rate, body temperature, systolic and diastolic blood pressure, etc.) to ensure the effectiveness of prophylactic and therapeutic measures is stressed.

  10. The association between biological rhythms, depression, and functioning in bipolar disorder: a large multi-center study.

    Science.gov (United States)

    Pinho, M; Sehmbi, M; Cudney, L E; Kauer-Sant'anna, M; Magalhães, P V; Reinares, M; Bonnín, C M; Sassi, R B; Kapczinski, F; Colom, F; Vieta, E; Frey, B N; Rosa, A R

    2015-05-22

    We examined the relationship between biological rhythms and severity of depressive symptoms in subjects with bipolar disorder and the effects of biological rhythms alterations on functional impairment. Bipolar patients (n = 260) and healthy controls (n = 191) were recruited from mood disorders programs in three sites (Spain, Brazil, and Canada). Parameters of biological rhythms were measured using the Biological Rhythms Assessment in Neuropsychiatry (BRIAN), an interviewer administered questionnaire that assesses disruptions in sleep, eating patterns, social rhythms, and general activity. Multivariate analyses of covariance showed significant intergroup differences after controlling for potential confounders (Pillai's F = 49.367; df = 2, P biological rhythms disturbance, followed by patients with subsyndromal symptoms, euthymic patients, and healthy controls. Biological rhythms and HAMD scores were independent predictors of poor functioning (F = 12.841, df = 6, P biological rhythms disturbance. Biological rhythms disturbance was also an independent predictor of functional impairment. Although the directionality of this relationship remains unknown, our results suggest that stability of biological rhythms should be an important target of acute and long-term management of bipolar disorder and may aid in the improvement of functioning. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Circadian rhythm sleep disorders

    Directory of Open Access Journals (Sweden)

    Morgenthaler TI

    2012-05-01

    Full Text Available Bhanu P Kolla,1,2 R Robert Auger,1,2 Timothy I Morgenthaler11Mayo Center for Sleep Medicine, 2Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USAAbstract: Misalignment between endogenous circadian rhythms and the light/dark cycle can result in pathological disturbances in the form of erratic sleep timing (irregular sleep–wake rhythm, complete dissociation from the light/dark cycle (circadian rhythm sleep disorder, free-running type, delayed sleep timing (delayed sleep phase disorder, or advanced sleep timing (advanced sleep phase disorder. Whereas these four conditions are thought to involve predominantly intrinsic mechanisms, circadian dysrhythmias can also be induced by exogenous challenges, such as those imposed by extreme work schedules or rapid transmeridian travel, which overwhelm the ability of the master clock to entrain with commensurate rapidity, and in turn impair approximation to a desired sleep schedule, as evidenced by the shift work and jet lag sleep disorders. This review will focus on etiological underpinnings, clinical assessments, and evidence-based treatment options for circadian rhythm sleep disorders. Topics are subcategorized when applicable, and if sufficient data exist. The length of text associated with each disorder reflects the abundance of associated literature, complexity of management, overlap of methods for assessment and treatment, and the expected prevalence of each condition within general medical practice.Keywords: circadian rhythm sleep disorders, assessment, treatment

  12. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    conditions, i.e., in the absence of any zeitgeber, organisms continue to exhibit rhythmicity, albeit with near 24-h periodicities, indicating that these rhythms are generated from within the ... well known for his work on thermoregulation, raised mice for ... technical terminologies proposed by him is still being used. In honor of his ...

  13. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 9. Circadian Rhythms - The ... Box 6436 Bangalore 560064, India. Chronobiology Laboratory Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, PO Box 6436 Bangalore 560064, India.

  14. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    pattern of behaviours could be a result of learning to be rhythmic under rhythmic environments during previous stages of that organism's life. However, experiments showing persistence of rhythms with a near 24 h period in organisms kept under constant environmental conditions for several generations clearly demon-.

  15. Circadian rhythms.

    Science.gov (United States)

    Turek, F W

    1998-01-01

    1997 marks the 25th anniversary of the discovery of the master circadian pacemaker in mammals in the hypothalamic suprachiasmatic nucleus. Remarkable progress has been made over the last 25 years in elucidating the physiological mechanisms involved in the entrainment, generation and expression of circadian rhythms at the cellular and systems levels. The recent discovery and cloning of the first mammalian clock gene is expected to lead to rapid advances in the understanding of the genetic and molecular mechanisms underlying circadian rhythmicity in mammals. Indeed, the impressive and extensive database on circadian rhythms in mammals obtained over the past 25 years provides a foundation for making rapid progress in utilizing future genetic and molecular findings for discovering the fundamental mechanisms controlling 24-hour temporal organization.

  16. Associations of the 24-h activity rhythm and sleep with cognition: a population-based study of middle-aged and elderly persons

    NARCIS (Netherlands)

    Luik, A.I.; Zuurbier, L.A.; Hofman, A.; van Someren, E.J.W.; Ikram, M.A.; Tiemeier, H.

    2015-01-01

    Background: Cognitive functioning changes with age, sleep, and the circadian rhythm. We investigated whether these factors are independently associated with different cognitive domains assessed in middle-aged and elderly persons. Methods: In 1723 middle-aged and elderly persons (age 62 ± 9.4 years,

  17. Associations of the 24-h activity rhythm and sleep with cognition : a population-based study of middle-aged and elderly persons

    NARCIS (Netherlands)

    Luik, Annemarie I; Zuurbier, Lisette A; Hofman, Albert; Van Someren, Eus J W; Ikram, M Arfan; Tiemeier, Henning

    BACKGROUND: Cognitive functioning changes with age, sleep, and the circadian rhythm. We investigated whether these factors are independently associated with different cognitive domains assessed in middle-aged and elderly persons. METHODS: In 1723 middle-aged and elderly persons (age 62 ± 9.4 years,

  18. Associations of the 24-h activity rhythm and sleep with cognition: A population-based study of middle-aged and elderly persons

    NARCIS (Netherlands)

    A.I. Luik (Annemarie); L.A. Zuurbier (Lisette); A. Hofman (Albert); E.J.W. van Someren (Eus); M.A. Ikram (Arfan); H.W. Tiemeier (Henning)

    2015-01-01

    textabstractBackground: Cognitive functioning changes with age, sleep, and the circadian rhythm. We investigated whether these factors are independently associated with different cognitive domains assessed in middle-aged and elderly persons. Methods: In 1723 middle-aged and elderly persons (age 62 ±

  19. Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation

    National Research Council Canada - National Science Library

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Diener, Hans-Christoph; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2015-01-01

    ...[Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-51...

  20. Serotonin and corticosterone rhythms in mice exposed to cigarette smoke and in patients with COPD: implication for COPD-associated neuropathogenesis.

    Directory of Open Access Journals (Sweden)

    Isaac K Sundar

    Full Text Available The circadian timing system controls daily rhythms of physiology and behavior, and disruption of clock function can trigger stressful life events. Daily exposure to cigarette smoke (CS can lead to alteration in diverse biological and physiological processes. Smoking is associated with mood disorders, including depression and anxiety. Patients with chronic obstructive pulmonary disease (COPD have abnormal circadian rhythms, reflected by daily changes in respiratory symptoms and lung function. Corticosterone (CORT is an adrenal steroid that plays a considerable role in stress and anti-inflammatory responses. Serotonin (5-hydroxytryptamine; 5HT is a neurohormone, which plays a role in sleep/wake regulation and affective disorders. Secretion of stress hormones (CORT and 5HT is under the control of the circadian clock in the suprachiasmatic nucleus. Since smoking is a contributing factor in the development of COPD, we hypothesize that CS can affect circadian rhythms of CORT and 5HT secretion leading to sleep and mood disorders in smokers and patients with COPD. We measured the daily rhythms of plasma CORT and 5HT in mice following acute (3 d, sub-chronic (10 d or chronic (6 mo CS exposure and in plasma from non-smokers, smokers and patients with COPD. Acute and chronic CS exposure affected both the timing (peak phase and amplitude of the daily rhythm of plasma CORT and 5HT in mice. Acute CS appeared to have subtle time-dependent effects on CORT levels but more pronounced effects on 5HT. As compared with CORT, plasma 5HT was slightly elevated in smokers but was reduced in patients with COPD. Thus, the effects of CS on plasma 5HT were consistent between mice and patients with COPD. Together, these data reveal a significant impact of CS exposure on rhythms of stress hormone secretion and subsequent detrimental effects on cognitive function, depression-like behavior, mood/anxiety and sleep quality in smokers and patients with COPD.

  1. Current investigation and management of patients with syncope

    DEFF Research Database (Denmark)

    Dagres, Nikolaos; Bongiorni, Maria Grazia; Dobreanu, Dan

    2013-01-01

    The aim of this European Heart Rhythm Association (EHRA) survey was to provide an insight into the current practice of work-up and management of patients with syncope among members of the EHRA electrophysiology research network. Responses were received from 43 centres. The majority of respondents...

  2. Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders

    NARCIS (Netherlands)

    den Hoed, M.A.H.; Eijgelsheim, M.; Esko, T.; Brundel, B.J.; Peal, D.S.; Evans, D.M.; Nolte, I.M.; Segrè, A.V.; Holm, H.; Handsaker, R.E.; Westra, H.J.; Johnson, T.; Isaacs, A.; Yang, L.; Lundby, A.; Zhao, J.H.; Kim, Y.J.; Go, M.J.; Almgren, P.; Bochud, M.; Boucher, G.; Cornelis, M.C.; Gudbjartsson, D.F.; Hadley, D.; van der Harst, P.; Hayward, C.; den Heijer, M.; Igl, W.; Jackson, A.U.; Kutalik, Z.; Luan, J.; Kemp, J.P.; Kristiansson, K.; Ladenvall, C.; Lorentzon, M.; Montasser, M.E.; Njajou, O.T.; O'Reilly, P.F.; Padmanabhan, S.; St Pourcain, B.; Rankinen, T.; Salo, P.; Tanaka, T.; Timpson, N.J.; Vitart, V.; Waite, L.; Wheeler, W.; Zhang, W.; Draisma, H.H.M.; Feitosa, M.F.; Kerr, K.F.; Lind, P.A.; Mihailov, E.; Onland-Moret, N.C.; Song, C.; Weedon, M.N.; Xie, W.; Yengo, L.; Absher, D.; Albert, C.M.; Alonso, A.; Arking, D.E.; de Bakker, P.I.; Balkau, B.; Barlassina, C.; Benaglio, P.; Bis, J.C.; Bouatia-Naji, N.; Brage, S.; Chanock, S.J.; Chines, P.S.; Chung, M.; Darbar, D.; Dina, C.; Dörr, M.; Elliott, P.; Felix, S.B.; Fischer, K.; Fuchsberger, C.; de Geus, E.J.C.; Goyette, P.; Gudnason, V.; Harris, T.B.; Hartikainen, A.L.; Havulinna, A.S.; Heckbert, S.R.; Hicks, A.A.; Hofman, A.; Holewijn, S.; Hoogstra-Berends, F.; Hottenga, J.J.; Jensen, M.K.; Johansson, A.; Junttila, J.; Kääb, S.; Kanon, B.; Ketkar, S.; Khaw, K.T.; Knowles, J.W.; Kooner, A.S.; Kors, J.A.; Kumari, M.; Milani, L.; Laiho, P.; Lakatta, E.G.; Langenberg, C.; Leusink, M.; Liu, Y.; Luben, R.N.; Lunetta, K.L.; Lynch, S.N.; Markus, M.R.; Marques-Vidal, P.; Mateo Leach, I.; McArdle, W.L.; McCarroll, S.A.; Medland, S.E.; Miller, K.A.; Montgomery, G.W.; Morrison, A.C.; Müller-Nurasyid, M.; Navarro, P.; Nelis, M.; O'Connell, J.R.; O'Donnell, C.J.; Ong, K.K.; Newman, A.B.; Peters, A.; Polasek, O.; Pouta, A.; Pramstaller, P.P.; Psaty, B.M.; Rao, D.C.; Ring, S.M.; Rossin, E.J.; Rudan, D.; Sanna, S.; Scott, R.A.; Sehmi, J.S.; Sharp, S.; Shin, J.T.; Singleton, A.B.; Smith, A.V.; Soranzo, N.; Spector, T.D.; Stewart, C.; Stringham, H.M.; Tarasov, K.V.; Uitterlinden, A.G.; Vandenput, L.; Hwang, S.J.; Whitfield, J.B.; Wijmenga, C.; Wild, S.H.; Willemsen, G.; Wilson, J.F.; Witteman, J.C.; Wong, A.; Wong, Q.; Jamshidi, Y.; Zitting, P.; Boer, J.M.; Boomsma, D.I.; Borecki, I.B.; van Duijn, C.M.; Ekelund, U.; Forouhi, N.G.; Froguel, P.; Hingorani, A.D.; Ingelsson, E.; Kivimaki, M.; Kronmal, R.A.; Kuh, D; Lind, L.; Martin, N.G.; Oostra, B.A.; Pedersen, N.L.; Quertermous, T.; Rotter, J.I.; van der Schouw, Y.T.; Verschuren, W.M.; Walker, M.; Albanes, D.; Arnar, D.O.; Assimes, T.L.; Bandinelli, S.; Boehnke, M.; de Boer, R.A.; Bouchard, C.; Caulfield, W.L.; Chambers, J.C.; Curhan, G.; Cusi, D.; Eriksson, J.; Ferrucci, L.; van Gilst, W.H.; Glorioso, N.; de Graaf, J.; Groop, L.; Gyllensten, U.; Hsueh, W.C.; Hu, F.B.; Huikuri, H.V.; Hunter, D.J.; Iribarren, C.; Isomaa, B.; Järvelin, M.R.; Jula, A.; Kähönen, M.; Kiemeney, L.A.; van der Klauw, M.M.; Kooner, J.S.; Kraft, P.; Iacoviello, L.; Lehtimäki, T.; Lokki, M.L.; Mitchell, B.D.; Navis, G.; Nieminen, M.S.; Ohlsson, C.; Poulter, N.R.; Qi, L.; Raitakari, O.T.; Rimm, E.B.; Rioux, J.D.; Rizzi, F.; Rudan, I.; Salomaa, V.; Sever, P.S.; Shields, D.C.; Shuldiner, A.R.; Sinisalo, J.; Stanton, A.V.; Stolk, R.P.; Strachan, D.P.; Tardif, J.C.; Thorsteinsdottir, U.; Tuomilehto, J.; van Veldhuisen, D.J.; Virtamo, J.; Viikari, J.; Vollenweider, P.; Waeber, G.; Widen, E.; Cho, Y.S.; Olsen, J.V.; Visscher, P.M.; Willer, C.J.; Franke, L; Erdmann, J.; Thompson, J.R.; Pfeufer, A.; Sotoodehnia, N.; Newton-Cheh, C.; Ellinor, P.T.; Stricker, B.H.C.; Metspalu, A.; Perola, M.; Beckmann, J.S.; Smith, G.D.; Stefansson, K.; Wareham, N.J.; Munroe, P.B.; Sibon, O.C.M.; Milan, D.J.; Snieder, H.; Samani, N.J.; Loos, R.J.

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously

  3. Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders

    DEFF Research Database (Denmark)

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously es...

  4. Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders

    NARCIS (Netherlands)

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tonu; Brundel, Bianca J. J. M.; Peal, David S.; Evans, David M.; Nolte, Ilja M.; Segre, Ayellet V.; Holm, Hilma; Handsaker, Robert E.; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia; Zhao, Jing Hua; Kim, Young Jin; Go, Min Jin; Almgren, Peter; Bochud, Murielle; Boucher, Gabrielle; Cornelis, Marilyn C.; Gudbjartsson, Daniel; Hadley, David; van der Harst, Pim; Hayward, Caroline; den Heijer, Martin; Igl, Wilmar; Jackson, Anne U.; Kutalik, Zoltan; Luan, Jian'an; Kemp, John P.; Kristiansson, Kati; Ladenvall, Claes; Lorentzon, Mattias; Montasser, May E.; Njajou, Omer T.; O'Reilly, Paul F.; Padmanabhan, Sandosh; Pourcain, Beate St.; Rankinen, Tuomo; Salo, Perttu; Tanaka, Toshiko; Timpson, Nicholas J.; Vitart, Veronique; Waite, Lindsay; Wheeler, William; Zhang, Weihua; Draisma, Harmen H. M.; Feitosa, Mary F.; Kerr, Kathleen F.; Lind, Penelope A.; Mihailov, Evelin; Onland-Moret, N. Charlotte; Song, Ci; Weedon, Michael N.; Xie, Weijia; Yengo, Loic; Absher, Devin; Albert, Christine M.; Alonso, Alvaro; Arking, Dan E.; de Bakker, Paul I. W.; Balkau, Beverley; Barlassina, Cristina; Benaglio, Paola; Bis, Joshua C.; Bouatia-Naji, Nabila; Brage, Soren; Chanock, Stephen J.; Chines, Peter S.; Chung, Mina; Darbar, Dawood; Dina, Christian; Doerr, Marcus; Elliott, Paul; Felix, Stephan B.; Fischer, Krista; Fuchsberger, Christian; de Geus, Eco J. C.; Goyette, Philippe; Gudnason, Vilmundur; Harris, Tamara B.; Hartikainen, Anna-Liisa; Havulinna, Aki S.; Heckbert, Susan R.; Hicks, Andrew A.; Hofman, Albert; Holewijn, Suzanne; Hoogstra-Berends, Femke; Hottenga, Jouke-Jan; Jensen, Majken K.; Johansson, Asa; Junttila, Juhani; Kaeaeb, Stefan; Kanon, Bart; Ketkar, Shamika; Khaw, Kay-Tee; Knowles, Joshua W.; Kooner, Angrad S.; Kors, Jan A.; Kumari, Meena; Milani, Lili; Laiho, Paeivi; Lakatta, Edward G.; Langenberg, Claudia; Leusink, Maarten; Liu, Yongmei; Luben, Robert N.; Lunetta, Kathryn L.; Lynch, Stacey N.; Markus, Marcello R. P.; Marques-Vidal, Pedro; Mateo Leach, Irene; McArdle, Wendy L.; McCarroll, Steven A.; Medland, Sarah E.; Miller, Kathryn A.; Montgomery, Grant W.; Morrison, Alanna C.; Mueller-Nurasyid, Martina; Navarro, Pau; Nelis, Mari; O'Connell, Jeffrey R.; O'Donnell, Christopher J.; Ong, Ken K.; Newman, Anne B.; Peters, Annette; Polasek, Ozren; Pouta, Anneli; Pramstaller, Peter P.; Psaty, Bruce M.; Rao, Dabeeru C.; Ring, Susan M.; Rossin, Elizabeth J.; Rudan, Diana; Sanna, Serena; Scott, Robert A.; Sehmi, Jaban S.; Sharp, Stephen; Shin, Jordan T.; Singleton, Andrew B.; Smith, Albert V.; Soranzo, Nicole; Spector, Tim D.; Stewart, Chip; Stringham, Heather M.; Tarasov, Kirill V.; Uitterlinden, Andre G.; Vandenput, Liesbeth; Hwang, Shih-Jen; Whitfield, John B.; Wijmenga, Cisca; Wild, Sarah H.; Willemsen, Gonneke; Wilson, James F.; Witteman, Jacqueline C. M.; Wong, Andrew; Wong, Quenna; Jamshidi, Yalda; Zitting, Paavo; Boer, Jolanda M. A.; Boomsma, Dorret I.; Borecki, Ingrid B.; van Duijn, Cornelia M.; Ekelund, Ulf; Forouhi, Nita G.; Froguel, Philippe; Hingorani, Aroon; Ingelsson, Erik; Kivimaki, Mika; Kronmal, Richard A.; Kuh, Diana; Lind, Lars; Martin, Nicholas G.; Oostra, Ben A.; Pedersen, Nancy L.; Quertermous, Thomas; Rotter, Jerome I.; van der Schouw, Yvonne T.; Verschuren, W. M. Monique; Walker, Mark; Albanes, Demetrius; Arnar, David O.; Assimes, Themistocles L.; Bandinelli, Stefania; Boehnke, Michael; de Boer, Rudolf A.; Bouchard, Claude; Caulfield, W. L. Mark; Chambers, John C.; Curhan, Gary; Cusi, Daniele; Eriksson, Johan; Ferrucci, Luigi; van Gilst, Wiek H.; Glorioso, Nicola; de Graaf, Jacqueline; Groop, Leif; Gyllensten, Ulf; Hsueh, Wen-Chi; Hu, Frank B.; Huikuri, Heikki V.; Hunter, David J.; Iribarren, Carlos; Isomaa, Bo; Jarvelin, Marjo-Riitta; Jula, Antti; Kahonen, Mika; Kiemeney, Lambertus A.; van der Klauw, Melanie M.; Kooner, Jaspal S.; Kraft, Peter; Iacoviello, Licia; Lehtimaki, Terho; Lokki, Marja-Liisa L.; Mitchell, Braxton D.; Navis, Gerjan; Nieminen, Markku S.; Ohlsson, Claes; Poulter, Neil R.; Qi, Lu; Raitakari, Olli T.; Rimm, Eric B.; Rioux, John D.; Rizzi, Federica; Rudan, Igor; Salomaa, Veikko; Sever, Peter S.; Shields, Denis C.; Shuldiner, Alan R.; Sinisalo, Juha; Stanton, Alice V.; Stolk, Ronald P.; Strachan, David P.; Tardif, Jean-Claude; Thorsteinsdottir, Unnur; Tuomilehto, Jaako; van Veldhuisen, Dirk J.; Virtamo, Jarmo; Viikari, Jorma; Vollenweider, Peter; Waeber, Gerard; Widen, Elisabeth; Cho, Yoon Shin; Olsen, Jesper V.; Visscher, Peter M.; Willer, Cristen; Franke, Lude; Erdmann, Jeanette; Thompson, John R.; Pfeufer, Arne; Sotoodehnia, Nona; Newton-Cheh, Christopher; Ellinor, Patrick T.; Stricker, Bruno H. Ch; Metspalu, Andres; Perola, Markus; Beckmann, Jacques S.; Smith, George Davey; Stefansson, Kari; Wareham, Nicholas J.; Munroe, Patricia B.; Sibon, Ody C. M.; Milan, David J.; Snieder, Harold; Samani, Nilesh J.; Loos, Ruth J. F.

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously

  5. Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders.

    Science.gov (United States)

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu; Brundel, Bianca J J M; Peal, David S; Evans, David M; Nolte, Ilja M; Segrè, Ayellet V; Holm, Hilma; Handsaker, Robert E; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia; Zhao, Jing Hua; Kim, Young Jin; Go, Min Jin; Almgren, Peter; Bochud, Murielle; Boucher, Gabrielle; Cornelis, Marilyn C; Gudbjartsson, Daniel; Hadley, David; van der Harst, Pim; Hayward, Caroline; den Heijer, Martin; Igl, Wilmar; Jackson, Anne U; Kutalik, Zoltán; Luan, Jian'an; Kemp, John P; Kristiansson, Kati; Ladenvall, Claes; Lorentzon, Mattias; Montasser, May E; Njajou, Omer T; O'Reilly, Paul F; Padmanabhan, Sandosh; St Pourcain, Beate; Rankinen, Tuomo; Salo, Perttu; Tanaka, Toshiko; Timpson, Nicholas J; Vitart, Veronique; Waite, Lindsay; Wheeler, William; Zhang, Weihua; Draisma, Harmen H M; Feitosa, Mary F; Kerr, Kathleen F; Lind, Penelope A; Mihailov, Evelin; Onland-Moret, N Charlotte; Song, Ci; Weedon, Michael N; Xie, Weijia; Yengo, Loic; Absher, Devin; Albert, Christine M; Alonso, Alvaro; Arking, Dan E; de Bakker, Paul I W; Balkau, Beverley; Barlassina, Cristina; Benaglio, Paola; Bis, Joshua C; Bouatia-Naji, Nabila; Brage, Søren; Chanock, Stephen J; Chines, Peter S; Chung, Mina; Darbar, Dawood; Dina, Christian; Dörr, Marcus; Elliott, Paul; Felix, Stephan B; Fischer, Krista; Fuchsberger, Christian; de Geus, Eco J C; Goyette, Philippe; Gudnason, Vilmundur; Harris, Tamara B; Hartikainen, Anna-Liisa; Havulinna, Aki S; Heckbert, Susan R; Hicks, Andrew A; Hofman, Albert; Holewijn, Suzanne; Hoogstra-Berends, Femke; Hottenga, Jouke-Jan; Jensen, Majken K; Johansson, Asa; Junttila, Juhani; Kääb, Stefan; Kanon, Bart; Ketkar, Shamika; Khaw, Kay-Tee; Knowles, Joshua W; Kooner, Angrad S; Kors, Jan A; Kumari, Meena; Milani, Lili; Laiho, Päivi; Lakatta, Edward G; Langenberg, Claudia; Leusink, Maarten; Liu, Yongmei; Luben, Robert N; Lunetta, Kathryn L; Lynch, Stacey N; Markus, Marcello R P; Marques-Vidal, Pedro; Mateo Leach, Irene; McArdle, Wendy L; McCarroll, Steven A; Medland, Sarah E; Miller, Kathryn A; Montgomery, Grant W; Morrison, Alanna C; Müller-Nurasyid, Martina; Navarro, Pau; Nelis, Mari; O'Connell, Jeffrey R; O'Donnell, Christopher J; Ong, Ken K; Newman, Anne B; Peters, Annette; Polasek, Ozren; Pouta, Anneli; Pramstaller, Peter P; Psaty, Bruce M; Rao, Dabeeru C; Ring, Susan M; Rossin, Elizabeth J; Rudan, Diana; Sanna, Serena; Scott, Robert A; Sehmi, Jaban S; Sharp, Stephen; Shin, Jordan T; Singleton, Andrew B; Smith, Albert V; Soranzo, Nicole; Spector, Tim D; Stewart, Chip; Stringham, Heather M; Tarasov, Kirill V; Uitterlinden, André G; Vandenput, Liesbeth; Hwang, Shih-Jen; Whitfield, John B; Wijmenga, Cisca; Wild, Sarah H; Willemsen, Gonneke; Wilson, James F; Witteman, Jacqueline C M; Wong, Andrew; Wong, Quenna; Jamshidi, Yalda; Zitting, Paavo; Boer, Jolanda M A; Boomsma, Dorret I; Borecki, Ingrid B; van Duijn, Cornelia M; Ekelund, Ulf; Forouhi, Nita G; Froguel, Philippe; Hingorani, Aroon; Ingelsson, Erik; Kivimaki, Mika; Kronmal, Richard A; Kuh, Diana; Lind, Lars; Martin, Nicholas G; Oostra, Ben A; Pedersen, Nancy L; Quertermous, Thomas; Rotter, Jerome I; van der Schouw, Yvonne T; Verschuren, W M Monique; Walker, Mark; Albanes, Demetrius; Arnar, David O; Assimes, Themistocles L; Bandinelli, Stefania; Boehnke, Michael; de Boer, Rudolf A; Bouchard, Claude; Caulfield, W L Mark; Chambers, John C; Curhan, Gary; Cusi, Daniele; Eriksson, Johan; Ferrucci, Luigi; van Gilst, Wiek H; Glorioso, Nicola; de Graaf, Jacqueline; Groop, Leif; Gyllensten, Ulf; Hsueh, Wen-Chi; Hu, Frank B; Huikuri, Heikki V; Hunter, David J; Iribarren, Carlos; Isomaa, Bo; Jarvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kiemeney, Lambertus A; van der Klauw, Melanie M; Kooner, Jaspal S; Kraft, Peter; Iacoviello, Licia; Lehtimäki, Terho; Lokki, Marja-Liisa L; Mitchell, Braxton D; Navis, Gerjan; Nieminen, Markku S; Ohlsson, Claes; Poulter, Neil R; Qi, Lu; Raitakari, Olli T; Rimm, Eric B; Rioux, John D; Rizzi, Federica; Rudan, Igor; Salomaa, Veikko; Sever, Peter S; Shields, Denis C; Shuldiner, Alan R; Sinisalo, Juha; Stanton, Alice V; Stolk, Ronald P; Strachan, David P; Tardif, Jean-Claude; Thorsteinsdottir, Unnur; Tuomilehto, Jaako; van Veldhuisen, Dirk J; Virtamo, Jarmo; Viikari, Jorma; Vollenweider, Peter; Waeber, Gérard; Widen, Elisabeth; Cho, Yoon Shin; Olsen, Jesper V; Visscher, Peter M; Willer, Cristen; Franke, Lude; Erdmann, Jeanette; Thompson, John R; Pfeufer, Arne; Sotoodehnia, Nona; Newton-Cheh, Christopher; Ellinor, Patrick T; Stricker, Bruno H Ch; Metspalu, Andres; Perola, Markus; Beckmann, Jacques S; Smith, George Davey; Stefansson, Kari; Wareham, Nicholas J; Munroe, Patricia B; Sibon, Ody C M; Milan, David J; Snieder, Harold; Samani, Nilesh J; Loos, Ruth J F

    2013-06-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate-increasing and heart rate-decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets.

  6. Identification of heart rate–associated loci and their effects on cardiac conduction and rhythm disorders

    Science.gov (United States)

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu; Brundel, Bianca J J M; Peal, David S; Evans, David M; Nolte, Ilja M; Segrè, Ayellet V; Holm, Hilma; Handsaker, Robert E; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia; Zhao, Jing Hua; Kim, Young Jin; Go, Min Jin; Almgren, Peter; Bochud, Murielle; Boucher, Gabrielle; Cornelis, Marilyn C; Gudbjartsson, Daniel; Hadley, David; Van Der Harst, Pim; Hayward, Caroline; Heijer, Martin Den; Igl, Wilmar; Jackson, Anne U; Kutalik, Zoltán; Luan, Jian’an; Kemp, John P; Kristiansson, Kati; Ladenvall, Claes; Lorentzon, Mattias; Montasser, May E; Njajou, Omer T; O’Reilly, Paul F; Padmanabhan, Sandosh; Pourcain, Beate St.; Rankinen, Tuomo; Salo, Perttu; Tanaka, Toshiko; Timpson, Nicholas J; Vitart, Veronique; Waite, Lindsay; Wheeler, William; Zhang, Weihua; Draisma, Harmen H M; Feitosa, Mary F; Kerr, Kathleen F; Lind, Penelope A; Mihailov, Evelin; Onland-Moret, N Charlotte; Song, Ci; Weedon, Michael N; Xie, Weijia; Yengo, Loic; Absher, Devin; Albert, Christine M; Alonso, Alvaro; Arking, Dan E; de Bakker, Paul I W; Balkau, Beverley; Barlassina, Cristina; Benaglio, Paola; Bis, Joshua C; Bouatia-Naji, Nabila; Brage, Søren; Chanock, Stephen J; Chines, Peter S; Chung, Mina; Darbar, Dawood; Dina, Christian; Dörr, Marcus; Elliott, Paul; Felix, Stephan B; Fischer, Krista; Fuchsberger, Christian; de Geus, Eco J C; Goyette, Philippe; Gudnason, Vilmundur; Harris, Tamara B; Hartikainen, Anna-liisa; Havulinna, Aki S; Heckbert, Susan R; Hicks, Andrew A; Hofman, Albert; Holewijn, Suzanne; Hoogstra-Berends, Femke; Hottenga, Jouke-Jan; Jensen, Majken K; Johansson, Åsa; Junttila, Juhani; Kääb, Stefan; Kanon, Bart; Ketkar, Shamika; Khaw, Kay-Tee; Knowles, Joshua W; Kooner, Angrad S; Kors, Jan A; Kumari, Meena; Milani, Lili; Laiho, Päivi; Lakatta, Edward G; Langenberg, Claudia; Leusink, Maarten; Liu, Yongmei; Luben, Robert N; Lunetta, Kathryn L; Lynch, Stacey N; Markus, Marcello R P; Marques-Vidal, Pedro; Leach, Irene Mateo; McArdle, Wendy L; McCarroll, Steven A; Medland, Sarah E; Miller, Kathryn A; Montgomery, Grant W; Morrison, Alanna C; Müller-Nurasyid, Martina; Navarro, Pau; Nelis, Mari; O’Connell, Jeffrey R; O’Donnell, Christopher J; Ong, Ken K; Newman, Anne B; Peters, Annette; Polasek, Ozren; Pouta, Anneli; Pramstaller, Peter P; Psaty, Bruce M; Rao, Dabeeru C; Ring, Susan M; Rossin, Elizabeth J; Rudan, Diana; Sanna, Serena; Scott, Robert A; Sehmi, Jaban S; Sharp, Stephen; Shin, Jordan T; Singleton, Andrew B; Smith, Albert V; Soranzo, Nicole; Spector, Tim D; Stewart, Chip; Stringham, Heather M; Tarasov, Kirill V; Uitterlinden, André G; Vandenput, Liesbeth; Hwang, Shih-Jen; Whitfield, John B; Wijmenga, Cisca; Wild, Sarah H; Willemsen, Gonneke; Wilson, James F; Witteman, Jacqueline C M; Wong, Andrew; Wong, Quenna; Jamshidi, Yalda; Zitting, Paavo; Boer, Jolanda M A; Boomsma, Dorret I; Borecki, Ingrid B; Van Duijn, Cornelia M; Ekelund, Ulf; Forouhi, Nita G; Froguel, Philippe; Hingorani, Aroon; Ingelsson, Erik; Kivimaki, Mika; Kronmal, Richard A; Kuh, Diana; Lind, Lars; Martin, Nicholas G; Oostra, Ben A; Pedersen, Nancy L; Quertermous, Thomas; Rotter, Jerome I; van der Schouw, Yvonne T; Verschuren, W M Monique; Walker, Mark; Albanes, Demetrius; Arnar, David O; Assimes, Themistocles L; Bandinelli, Stefania; Boehnke, Michael; de Boer, Rudolf A; Bouchard, Claude; Caulfield, W L Mark; Chambers, John C; Curhan, Gary; Cusi, Daniele; Eriksson, Johan; Ferrucci, Luigi; van Gilst, Wiek H; Glorioso, Nicola; de Graaf, Jacqueline; Groop, Leif; Gyllensten, Ulf; Hsueh, Wen-Chi; Hu, Frank B; Huikuri, Heikki V; Hunter, David J; Iribarren, Carlos; Isomaa, Bo; Jarvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kiemeney, Lambertus A; van der Klauw, Melanie M; Kooner, Jaspal S; Kraft, Peter; Iacoviello, Licia; Lehtimäki, Terho; Lokki, Marja-Liisa L; Mitchell, Braxton D; Navis, Gerjan; Nieminen, Markku S; Ohlsson, Claes; Poulter, Neil R; Qi, Lu; Raitakari, Olli T; Rimm, Eric B; Rioux, John D; Rizzi, Federica; Rudan, Igor; Salomaa, Veikko; Sever, Peter S; Shields, Denis C; Shuldiner, Alan R; Sinisalo, Juha; Stanton, Alice V; Stolk, Ronald P; Strachan, David P; Tardif, Jean-Claude; Thorsteinsdottir, Unnur; Tuomilehto, Jaako; van Veldhuisen, Dirk J; Virtamo, Jarmo; Viikari, Jorma; Vollenweider, Peter; Waeber, Gérard; Widen, Elisabeth; Cho, Yoon Shin; Olsen, Jesper V; Visscher, Peter M; Willer, Cristen; Franke, Lude; Erdmann, Jeanette; Thompson, John R; Pfeufer, Arne; Sotoodehnia, Nona; Newton-Cheh, Christopher; Ellinor, Patrick T; Stricker, Bruno H Ch; Metspalu, Andres; Perola, Markus; Beckmann, Jacques S; Smith, George Davey; Stefansson, Kari; Wareham, Nicholas J; Munroe, Patricia B; Sibon, Ody C M; Milan, David J; Snieder, Harold; Samani, Nilesh J; Loos, Ruth J F

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate–increasing and heart rate–decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets. PMID:23583979

  7. Dissipative structures and biological rhythms

    Science.gov (United States)

    Goldbeter, Albert

    2017-10-01

    Sustained oscillations abound in biological systems. They occur at all levels of biological organization over a wide range of periods, from a fraction of a second to years, and with a variety of underlying mechanisms. They control major physiological functions, and their dysfunction is associated with a variety of physiological disorders. The goal of this review is (i) to give an overview of the main rhythms observed at the cellular and supracellular levels, (ii) to briefly describe how the study of biological rhythms unfolded in the course of time, in parallel with studies on chemical oscillations, (iii) to present the major roles of biological rhythms in the control of physiological functions, and (iv) the pathologies associated with the alteration, disappearance, or spurious occurrence of biological rhythms. Two tables present the main examples of cellular and supracellular rhythms ordered according to their period, and their role in physiology and pathophysiology. Among the rhythms discussed are neural and cardiac rhythms, metabolic oscillations such as those occurring in glycolysis in yeast, intracellular Ca++ oscillations, cyclic AMP oscillations in Dictyostelium amoebae, the segmentation clock that controls somitogenesis, pulsatile hormone secretion, circadian rhythms which occur in all eukaryotes and some bacteria with a period close to 24 h, the oscillatory dynamics of the enzymatic network driving the cell cycle, and oscillations in transcription factors such as NF-ΚB and tumor suppressors such as p53. Ilya Prigogine's concept of dissipative structures applies to temporal oscillations and allows us to unify within a common framework the various rhythms observed at different levels of biological organization, regardless of their period and underlying mechanism.

  8. Seasonal feeding rhythm associated with fasting period of Pangasianodon gigas: long-term monitoring in an aquarium.

    Science.gov (United States)

    Ikeya, Koki; Kume, Manabu

    2011-08-01

    The Mekong giant catfish Pangasianodon gigas is endemic to the Mekong River basin, and is recognized as endangered species, largely due to overfishing and development of the river basin. We monitored food intake of P. gigas in a stable environment in an aquarium over a 6-year period and analyzed their feeding rhythm and fasting periods. The daily food intake for each fish was recorded from 18 June 2004 to 17 June 2010. The feeding rhythm or pattern was determined by the fast Fourier transform (FFT) analysis. The FFT analysis revealed that different cycles of feeding rhythm (168.8, 313.1, and 365.3 days) in three catfishes and no observable cycles in two catfishes. However, three catfishes showed subordinate peaks with approximately 365 days (365.3 days for all). These suggest that, at least, four of five catfish had have approximately 365-days feeding cycle. We also showed that all catfish undergo long-term fasting periods (> 20 days). Of note, the feeding/fasting pattern coincides with the wet/dry seasons in Thailand, which also corresponds to the abundance of the catfish food resource (Cladophora spp.). We found that P. gigas exhibit a seasonal feeding rhythm that is synchronized by food availability. Furthermore, we found that the seasonal feeding rhythm was gradually dampened over time, suggesting that the observed seasonal feeding rhythm with long-term fasting of the catfish is likely controlled by an endogenous clock system. To our knowledge, this is the first case of quantification of the seasonal feeding rhythm with fasting periods in teleost fish.

  9. Analysis of 24-h Rhythm in Ventricular Repolarization Identifies QT Diurnality As a Novel Clinical Parameter Associated with Previous Ventricular Arrhythmias in Heart Failure Patients

    Directory of Open Access Journals (Sweden)

    Bastiaan C. Du Pre

    2017-08-01

    Full Text Available Introduction: Cardiac repolarization abnormalities are among the major causes of ventricular arrhythmias and sudden cardiac death. In humans, cardiac repolarization duration has a 24-h rhythm. Animal studies show that this rhythm is regulated by 24-h rhythms in ion channel function and that disruption of this rhythm leads to ventricular arrhythmias. We hypothesized that 24-h rhythms in QT duration can be used as a predictor for sudden cardiac death and are associated with ventricular arrhythmias. Secondly, we assessed a possible mechanistic explanation by studying the putative role of hERG channel dysfunction.Materials and Methods: In 2 retrospective studies, measures of the 24-h variation in the QT and QTc intervals (QT and QTc diurnality, QTd and QTcd, respectively have been derived from Holter analyses and compared between groups: 1 39 post-infarct patients with systolic heart failure (CHF: EF < 35%, of which 14 with, and 25 without a history of ventricular arrhythmias and 2 five patients with proven (LQTS2 and 16 with potential (Sotalol-induced hERG channel dysfunction vs. 22 controls.Results: QTd was two-fold higher in CHF patients with a history of ventricular arrhythmias (38 ± 15 ms compared to CHF patients without VT (16 ± 9 ms, p = 0.001. QTd was significantly increased in LQT2 patients (43 ± 24 ms or those treated with Sotalol (30 ± 10 ms compared to controls (21 ± 8 ms, p < 0.05 for both.Discussion: QT diurnality presents a novel clinical parameter of repolarization that can be derived from Holter registrations and may be useful for identification of patients at risk for ventricular arrhythmias.

  10. Delirium - A Dysfunctional Circadian Rhythm

    OpenAIRE

    Eckle T

    2016-01-01

    Critical care units are a major cause of a disrupted circadian rhythm in patients [1, 2]. Light, noise, treatments, sedatives and mechanical ventilation throughout a 24 h time period are the major offenders of circadian rhythm disruption in the intensive care unit [ICU] [2]. Interestingly, circadian disruption is frequently associated with the occurrence of delirium having a high impact on outcome and mortality in the critically ill [3-5]. Endogenous melatonin, a mirror of our circadian rhyth...

  11. A high performance sensorimotor beta rhythm-based brain computer interface associated with human natural motor behavior

    Science.gov (United States)

    Bai, Ou; Lin, Peter; Vorbach, Sherry; Floeter, Mary Kay; Hattori, Noriaki; Hallett, Mark

    2008-03-01

    To explore the reliability of a high performance brain-computer interface (BCI) using non-invasive EEG signals associated with human natural motor behavior does not require extensive training. We propose a new BCI method, where users perform either sustaining or stopping a motor task with time locking to a predefined time window. Nine healthy volunteers, one stroke survivor with right-sided hemiparesis and one patient with amyotrophic lateral sclerosis (ALS) participated in this study. Subjects did not receive BCI training before participating in this study. We investigated tasks of both physical movement and motor imagery. The surface Laplacian derivation was used for enhancing EEG spatial resolution. A model-free threshold setting method was used for the classification of motor intentions. The performance of the proposed BCI was validated by an online sequential binary-cursor-control game for two-dimensional cursor movement. Event-related desynchronization and synchronization were observed when subjects sustained or stopped either motor execution or motor imagery. Feature analysis showed that EEG beta band activity over sensorimotor area provided the largest discrimination. With simple model-free classification of beta band EEG activity from a single electrode (with surface Laplacian derivation), the online classifications of the EEG activity with motor execution/motor imagery were: >90%/~80% for six healthy volunteers, >80%/~80% for the stroke patient and ~90%/~80% for the ALS patient. The EEG activities of the other three healthy volunteers were not classifiable. The sensorimotor beta rhythm of EEG associated with human natural motor behavior can be used for a reliable and high performance BCI for both healthy subjects and patients with neurological disorders. Significance: The proposed new non-invasive BCI method highlights a practical BCI for clinical applications, where the user does not require extensive training.

  12. Fragmentation and stability of circadian activity rhythms predict mortality : the rotterdam study

    NARCIS (Netherlands)

    Zuurbier, Lisette A; Luik, Annemarie I; Hofman, Albert; Franco, Oscar H; Van Someren, Eus J W; Tiemeier, Henning

    2015-01-01

    Circadian rhythms and sleep patterns change as people age. Little is known about the associations between circadian rhythms and mortality rates. We investigated whether 24-hour activity rhythms and sleep characteristics independently predicted mortality. Actigraphy was used to determine the

  13. Association of Amplitude and Stability of Circadian Rhythm, Sleep Quality, and Occupational Stress with Sickness Absence among a Gas Company Employees-A Cross Sectional Study from Iran.

    Science.gov (United States)

    Zare, Rezvan; Choobineh, Alireza; Keshavarzi, Sareh

    2017-09-01

    The present study was carried out to assess the relationship between sickness absence and occupational stress, sleep quality, and amplitude and stability of circadian rhythm as well as to determine contributing factors of sickness absence. This cross sectional study was conducted on 400 randomly selected employees of an Iranian gas company. The data were collected using Pittsburgh sleep quality index, Karolinska sleepiness scale, circadian type inventory, and Osipow occupational stress questionnaires. The mean age and job tenure of the participants were 33.18 ± 5.64 years and 6.06 ± 4.99 years, respectively. Also, the participants had been absent from work on average 2.16 days a year. According to the results, 209 participants had no absences, 129 participants had short-term absences, and 62 participants had long-term absences. The results showed a significant relationship between short-term absenteeism and amplitude of circadian rhythm [odds ratio (OR) = 6.13], sleep quality (OR = 14.46), sleepiness (OR = 2.08), role boundary (OR = 6.45), and responsibility (OR = 5.23). Long-term absenteeism was also significantly associated with amplitude of circadian rhythm (OR = 2.42), sleep quality (OR = 21.56), sleepiness (OR = 6.44), role overload (OR = 4.84), role boundary (OR = 4.27), and responsibility (OR = 3.72). The results revealed that poor sleep quality, amplitude of circadian rhythm, and occupational stress were the contributing factors for sickness absence in the study population.

  14. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F

    2017-12-07

    Circadian rhythms enable organisms to synchronise the processes underpinning survival and reproduction to anticipate daily changes in the external environment. Recent work shows that daily (circadian) rhythms also enable parasites to maximise fitness in the context of ecological interactions with their hosts. Because parasite rhythms matter for their fitness, understanding how they are regulated could lead to innovative ways to reduce the severity and spread of diseases. Here, we examine how host circadian rhythms influence rhythms in the asexual replication of malaria parasites. Asexual replication is responsible for the severity of malaria and fuels transmission of the disease, yet, how parasite rhythms are driven remains a mystery. We perturbed feeding rhythms of hosts by 12 hours (i.e. diurnal feeding in nocturnal mice) to desynchronise the host\\'s peripheral oscillators from the central, light-entrained oscillator in the brain and their rhythmic outputs. We demonstrate that the rhythms of rodent malaria parasites in day-fed hosts become inverted relative to the rhythms of parasites in night-fed hosts. Our results reveal that the host\\'s peripheral rhythms (associated with the timing of feeding and metabolism), but not rhythms driven by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms resynchronise to the altered host feeding rhythms when food availability is shifted, which is not mediated through rhythms in the host immune system. Our observations suggest that parasites actively control their developmental rhythms. Finally, counter to expectation, the severity of disease symptoms expressed by hosts was not affected by desynchronisation of their central and peripheral rhythms. Our study at the intersection of disease ecology and chronobiology opens up a new

  15. Improvement of a patient's circadian rhythm sleep disorders by aripiprazole was associated with stabilization of his bipolar illness.

    Science.gov (United States)

    Tashiro, Tetsuo

    2017-04-01

    Splitting of the behavioural activity phase has been found in nocturnal rodents with suprachiasmatic nucleus (SCN) coupling disorder. A similar phenomenon was observed in the sleep phase in the diurnal human discussed here, suggesting that there are so-called evening and morning oscillators in the SCN of humans. The present case suffered from bipolar disorder refractory to various treatments, and various circadian rhythm sleep disorders, such as delayed sleep phase, polyphasic sleep, separation of the sleep bout resembling splitting and circabidian rhythm (48 h), were found during prolonged depressive episodes with hypersomnia. Separation of sleep into evening and morning components and delayed sleep-offset (24.69-h cycle) developed when lowering and stopping the dose of aripiprazole (APZ). However, resumption of APZ improved these symptoms in 2 weeks, accompanied by improvement in the patient's depressive state. Administration of APZ may improve various circadian rhythm sleep disorders, as well as improve and prevent manic-depressive episodes, via augmentation of coupling in the SCN network. © 2017 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

  16. The Prospective Association of the Diurnal Cortisol Rhythm With Sleep Duration and Perceived Sleeping Problems in Preschoolers: The Generation R Study.

    Science.gov (United States)

    Saridjan, Nathalie S; Kocevska, Desana; Luijk, Maartje P C M; Jaddoe, Vincent W V; Verhulst, Frank C; Tiemeier, Henning

    2017-06-01

    Cortisol, the end product of the hypothalamic-pituitary-adrenal axis, plays an important role in modulating sleep. Yet, studies investigating the association between diurnal cortisol rhythm and sleep patterns in young children are scarce. We tested the hypothesis that the diurnal cortisol rhythm is associated with shorter sleep duration and more sleep problems across early childhood. This study was embedded in Generation R, a population-based cohort from fetal life onward. Parents collected saliva samples from their infant at five moments during day 1. In 322 infants aged 12 to 20 months, we determined the diurnal cortisol rhythm by calculating the area under the curve (AUC), the cortisol awakening response (CAR), and the diurnal slope. Sleep duration and sleep behavior were repeatedly assessed across ages of 14 months to 5 years. Generalized estimating equation models were used to assess related cortisol measures to sleep duration and sleep behavior. The diurnal cortisol slope and the CAR, but not the AUC, were associated with sleep duration across childhood. Children with flatter slopes and children with a more positive CAR were more likely to have shorter nighttime sleep duration (β per nmol/L/h slope = -0.12, 95% confidence interval = -0.19 to -0.05, p = .001; β per nmol/L CAR = -0.01, 95% confidence interval = -0.02 to 0.00, p = .04). Cortisol measures did not predict sleep problems. The present study suggests that a flatter diurnal cortisol slope and a more marked morning rise, which can indicate stress (or hypothalamic-pituitary-adrenal dysregulation), have a long-term association with sleep regulation.

  17. A different rhythm of life: sleep patterns in the first 4 years of life and associated sociodemographic characteristics in a large Brazilian birth cohort.

    Science.gov (United States)

    Netsi, Elena; Santos, Ina S; Stein, Alan; Barros, Fernando C; Barros, Aluísio J D; Matijasevich, Alicia

    2017-09-01

    Sleep is an important marker of healthy development and has been associated with emotional, behavioral, and cognitive development. There is limited longitudinal data on children's sleep with only a few reports from low- and middle-income countries (LMICs). We investigate sleep parameters and associated sociodemographic characteristics in a population-based longitudinal study in Pelotas, Brazil. Data from the Pelotas 2004 Birth Cohort were used (N = 3842). Infant sleep was collected through maternal report at 3, 12, 24, and 48 months: sleep duration, bed and wake time, nighttime awakenings, co-sleeping and sleep disturbances (24 and 48 months). Compared to children in high-income countries (HICs), children in Brazil showed a substantial shift in rhythms with later bed and wake times by approximately 2 hours. These remain stable throughout the first 4 years of life. This population also shows high levels of co-sleeping which remain stable throughout (49.0-52.2%). Later bedtime was associated with higher maternal education and family income. Higher rates of co-sleeping were seen in families with lower income and maternal education and for children who were breastfed. All other sleep parameters were broadly similar to data previously reported from HICs. The shift in biological rhythms in this representative community sample of children in Brazil challenges our understanding of optimal sleep routine and recommendations. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  18. Biological rhythms and preeclampsia

    Directory of Open Access Journals (Sweden)

    Agnès eDitisheim

    2013-04-01

    Full Text Available The impact of impaired circadian rhythm on health has been widely studied in shift workers and trans-meridian travelers. A part from its correlation with sleep and mood disorders, biological rhythm impairment is a recognized risk factor for cardiovascular diseases and breast cancer.Preeclampsia is a major public health issue, associated with a significant maternal and fetal morbidity and mortality worldwide. While the risks factors for this condition such as obesity, diabetes, pre-existing hypertension have been identified, the underlying mechanism of this multi-factorial disease is yet not fully understood.The disruption of the light/dark cycle in pregnancy has been associated with adverse outcomes. Slightly increased risk for small for gestational age babies, low birth weight babies and preterm deliveries has been reported in shift working women. Whether altered circadian cycle represents a risk factor for preeclampsia or preeclampsia is itself linked with an abnormal circadian cycle is less clear. There are only few reports available, showing conflicting results. In this review, we will discuss recent observations concerning circadian pattern of blood pressure in normotensive and hypertensive pregnancies. We explore the hypothesis that circadian misalignments may represent a risk factor for preeclampsia. Unraveling potential link between circadian clock gene and preeclampsia could offer a novel approach to our understanding of this multi-system disease specific to pregnancy.

  19. ADHD, circadian rhythms and seasonality

    NARCIS (Netherlands)

    Wynchank, Dora S.; Bijlenga, Denise; Lamers, Femke; Bron, Tannetje I.; Winthorst, Wim H.; Vogel, Suzan W.; Penninx, Brenda W.; Beekman, Aartjan T.; Kooij, J. Sandra

    2016-01-01

    Objective: We evaluated whether the association between Adult Attention-Deficit/Hyperactivity Disorder (ADHD) and Seasonal Affective Disorder (SAD) was mediated by the circadian rhythm. Method: Data of 2239 persons from the Netherlands Study of Depression and Anxiety (NESDA) were used. Two groups

  20. Expression of MEP Pathway Genes and Non-volatile Sequestration Are Associated with Circadian Rhythm of Dominant Terpenoids Emission in Osmanthus fragrans Lour. Flowers

    Directory of Open Access Journals (Sweden)

    Riru Zheng

    2017-10-01

    Full Text Available Osmanthus fragrans Lour. is one of the top 10 traditional ornamental flowers in China famous for its unique fragrance. Preliminary study proved that the terpenoids including ionone, linalool, and ocimene and their derivatives are the dominant aroma-active compounds that contribute greatly to the scent bouquet. Pollination observation implies the emission of aromatic terpenoids may follow a circadian rhythm. In this study, we investigated the variation of volatile terpenoids and its potential regulators. The results showed that both volatile and non-volatile terpenoids presented circadian oscillation with high emission or accumulation during the day and low emission or accumulation during the night. The volatile terpenoids always increased to reach their maximum values at 12:00 h, while free and glycosylated compounds continued increasing throughout the day. The depletion of non-volatile pool might provide the substrates for volatile emission at 0:00–6:00, suggesting the sequestration of non-volatile compounds acted like a buffer regulating emission of terpenoids. Further detection of MEP pathway genes demonstrated that their expressions increased significantly in parallel with the evident increase of both volatile and non-volatile terpenoids during the day, indicating that the gene expressions were also closely associated with terpenoid formation. Thus, the expression of MEP pathway genes and internal sequestration both played crucial roles in modulating circadian rhythm of terpenoid emission in O. fragrans.

  1. Expression of MEP Pathway Genes and Non-volatile Sequestration Are Associated with Circadian Rhythm of Dominant Terpenoids Emission in Osmanthus fragrans Lour. Flowers.

    Science.gov (United States)

    Zheng, Riru; Liu, Cai; Wang, Yanli; Luo, Jing; Zeng, Xiangling; Ding, Haiqin; Xiao, Wei; Gan, Jianping; Wang, Caiyun

    2017-01-01

    Osmanthus fragrans Lour. is one of the top 10 traditional ornamental flowers in China famous for its unique fragrance. Preliminary study proved that the terpenoids including ionone, linalool, and ocimene and their derivatives are the dominant aroma-active compounds that contribute greatly to the scent bouquet. Pollination observation implies the emission of aromatic terpenoids may follow a circadian rhythm. In this study, we investigated the variation of volatile terpenoids and its potential regulators. The results showed that both volatile and non-volatile terpenoids presented circadian oscillation with high emission or accumulation during the day and low emission or accumulation during the night. The volatile terpenoids always increased to reach their maximum values at 12:00 h, while free and glycosylated compounds continued increasing throughout the day. The depletion of non-volatile pool might provide the substrates for volatile emission at 0:00-6:00, suggesting the sequestration of non-volatile compounds acted like a buffer regulating emission of terpenoids. Further detection of MEP pathway genes demonstrated that their expressions increased significantly in parallel with the evident increase of both volatile and non-volatile terpenoids during the day, indicating that the gene expressions were also closely associated with terpenoid formation. Thus, the expression of MEP pathway genes and internal sequestration both played crucial roles in modulating circadian rhythm of terpenoid emission in O. fragrans.

  2. Circadian rhythm sleep disorders

    OpenAIRE

    Morgenthaler TI; Auger RR; Kolla BP

    2012-01-01

    Bhanu P Kolla,1,2 R Robert Auger,1,2 Timothy I Morgenthaler11Mayo Center for Sleep Medicine, 2Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USAAbstract: Misalignment between endogenous circadian rhythms and the light/dark cycle can result in pathological disturbances in the form of erratic sleep timing (irregular sleep–wake rhythm), complete dissociation from the light/dark cycle (circadian rhythm sleep disorder, free-running type), delayed...

  3. Rhythm Training through Movement.

    Science.gov (United States)

    Riveire, Janine H.

    1995-01-01

    Maintains that string playing, rhythm, pitch, and tone quality are all dependent on the movement and coordination of the player. Presents a rhythmic focus lesson plan for students who need improvement in rhythm skills. Includes a lesson plan diagram and suggested teacher resources. (CFR)

  4. Markets, Bodies, Rhythms

    DEFF Research Database (Denmark)

    Borch, Christian; Bondo Hansen, Kristian; Lange, Ann-Christina

    2015-01-01

    This article explores the relationship between bodily rhythms and market rhythms in two distinctly different financial market configurations, namely the open-outcry pit (prevalent especially in the early 20th century) and present-day high-frequency trading. Drawing on Henri Lefebvre's rhythmanaly......This article explores the relationship between bodily rhythms and market rhythms in two distinctly different financial market configurations, namely the open-outcry pit (prevalent especially in the early 20th century) and present-day high-frequency trading. Drawing on Henri Lefebvre...... of financial markets, it also suggests that high-frequency trading in particular might produce new types of market rhythms that, contra Lefebvre, do not revolve around traders' bodies....

  5. Is there an association between external cardioversions and long-term mortality and morbidity? Insights from the Atrial Fibrillation Follow-up Investigation of Rhythm Management study.

    Science.gov (United States)

    Elayi, Claude S; Whitbeck, Matthew G; Charnigo, Richard; Shah, Jignesh; Macaulay, Tracy E; Morales, Gustavo; Gurley, John C; Kakavand, Bahram; Thal, Sergio; Ching, Chi Keong; Khaykin, Yaariv; Verma, Atul; Barrett, Conor; Bai, Rong; Di Biase, Luigi; Patwardhan, Abhijit; Moliterno, David J; Natale, Andrea

    2011-08-01

    Cardiac electric therapies effectively terminate tachyarrhythmias. Recent data suggest a possible increase in long-term mortality associated with implantable cardioverter-defibrillator shocks. Little is known about the association between external cardioversion episodes (ECVe) and long-term mortality. We sought to assess the safety of repeated ECVe with regard to cardiovascular mortality and morbidity. We analyzed the data of the 4060 patients from the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) trial. In particular, associations of ECVe with all-cause mortality, cardiovascular mortality, and hospitalizations after ECVe were studied. Over an average follow-up of 3.5 years, 660 (16.3%) patients died, 331 (8.2%) from cardiovascular causes. A total of 207 (5.1%) and 1697 (41.8%) patients had low ejection fraction and nonparoxysmal atrial fibrillation, respectively; 2460 patients received no ECVe, whereas 1600 experienced ≥ 1 ECVe. Death occurred in 412 (16.7%), 196 (16.5%), 39 (13.5%), and 13 (10.4%) of patients with 0, 1, 2, and ≥ 3 ECVe, respectively. There was no significant association between ECVe and mortality within any of the 4 subgroups defined by ejection fraction and atrial fibrillation type, although myocardial infarction, coronary artery bypass graft, and digoxin were significantly associated with death (estimated hazard ratios, 1.65, 1.59, and 1.62, respectively; P Digoxin, myocardial infarction, and coronary artery bypass graft were significantly associated with mortality.

  6. Rhythm in language acquisition.

    Science.gov (United States)

    Langus, Alan; Mehler, Jacques; Nespor, Marina

    2017-10-01

    Spoken language is governed by rhythm. Linguistic rhythm is hierarchical and the rhythmic hierarchy partially mimics the prosodic as well as the morpho-syntactic hierarchy of spoken language. It can thus provide learners with cues about the structure of the language they are acquiring. We identify three universal levels of linguistic rhythm - the segmental level, the level of the metrical feet and the phonological phrase level - and discuss why primary lexical stress is not rhythmic. We survey experimental evidence on rhythm perception in young infants and native speakers of various languages to determine the properties of linguistic rhythm that are present at birth, those that mature during the first year of life and those that are shaped by the linguistic environment of language learners. We conclude with a discussion of the major gaps in current knowledge on linguistic rhythm and highlight areas of interest for future research that are most likely to yield significant insights into the nature, the perception, and the usefulness of linguistic rhythm. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. 24-hour rhythms of DNA methylation and their relation with rhythms of RNA expression in the human dorsolateral prefrontal cortex.

    Science.gov (United States)

    Lim, Andrew S P; Srivastava, Gyan P; Yu, Lei; Chibnik, Lori B; Xu, Jishu; Buchman, Aron S; Schneider, Julie A; Myers, Amanda J; Bennett, David A; De Jager, Philip L

    2014-11-01

    Circadian rhythms modulate the biology of many human tissues, including brain tissues, and are driven by a near 24-hour transcriptional feedback loop. These rhythms are paralleled by 24-hour rhythms of large portions of the transcriptome. The role of dynamic DNA methylation in influencing these rhythms is uncertain. While recent work in Neurospora suggests that dynamic site-specific circadian rhythms of DNA methylation may play a role in modulating the fungal molecular clock, such rhythms and their relationship to RNA expression have not, to our knowledge, been elucidated in mammalian tissues, including human brain tissues. We hypothesized that 24-hour rhythms of DNA methylation exist in the human brain, and play a role in driving 24-hour rhythms of RNA expression. We analyzed DNA methylation levels in post-mortem human dorsolateral prefrontal cortex samples from 738 subjects. We assessed for 24-hour rhythmicity of 420,132 DNA methylation sites throughout the genome by considering methylation levels as a function of clock time of death and parameterizing these data using cosine functions. We determined global statistical significance by permutation. We then related rhythms of DNA methylation with rhythms of RNA expression determined by RNA sequencing. We found evidence of significant 24-hour rhythmicity of DNA methylation. Regions near transcription start sites were enriched for high-amplitude rhythmic DNA methylation sites, which were in turn time locked to 24-hour rhythms of RNA expression of nearby genes, with the nadir of methylation preceding peak transcript expression by 1-3 hours. Weak ante-mortem rest-activity rhythms were associated with lower amplitude DNA methylation rhythms as were older age and the presence of Alzheimer's disease. These findings support the hypothesis that 24-hour rhythms of DNA methylation, particularly near transcription start sites, may play a role in driving 24-hour rhythms of gene expression in the human dorsolateral prefrontal

  8. 24-hour rhythms of DNA methylation and their relation with rhythms of RNA expression in the human dorsolateral prefrontal cortex.

    Directory of Open Access Journals (Sweden)

    Andrew S P Lim

    2014-11-01

    Full Text Available Circadian rhythms modulate the biology of many human tissues, including brain tissues, and are driven by a near 24-hour transcriptional feedback loop. These rhythms are paralleled by 24-hour rhythms of large portions of the transcriptome. The role of dynamic DNA methylation in influencing these rhythms is uncertain. While recent work in Neurospora suggests that dynamic site-specific circadian rhythms of DNA methylation may play a role in modulating the fungal molecular clock, such rhythms and their relationship to RNA expression have not, to our knowledge, been elucidated in mammalian tissues, including human brain tissues. We hypothesized that 24-hour rhythms of DNA methylation exist in the human brain, and play a role in driving 24-hour rhythms of RNA expression. We analyzed DNA methylation levels in post-mortem human dorsolateral prefrontal cortex samples from 738 subjects. We assessed for 24-hour rhythmicity of 420,132 DNA methylation sites throughout the genome by considering methylation levels as a function of clock time of death and parameterizing these data using cosine functions. We determined global statistical significance by permutation. We then related rhythms of DNA methylation with rhythms of RNA expression determined by RNA sequencing. We found evidence of significant 24-hour rhythmicity of DNA methylation. Regions near transcription start sites were enriched for high-amplitude rhythmic DNA methylation sites, which were in turn time locked to 24-hour rhythms of RNA expression of nearby genes, with the nadir of methylation preceding peak transcript expression by 1-3 hours. Weak ante-mortem rest-activity rhythms were associated with lower amplitude DNA methylation rhythms as were older age and the presence of Alzheimer's disease. These findings support the hypothesis that 24-hour rhythms of DNA methylation, particularly near transcription start sites, may play a role in driving 24-hour rhythms of gene expression in the human

  9. The role of the Arrhythmia Team, an integrated, multidisciplinary approach to treatment of patients with cardiac arrhythmias: results of the European Heart Rhythm Association survey.

    Science.gov (United States)

    Fumagalli, Stefano; Chen, Jian; Dobreanu, Dan; Madrid, Antonio Hernandez; Tilz, Roland; Dagres, Nikolaos

    2016-04-01

    Management of patients with cardiac arrhythmias is increasingly complex because of continuous technological advance and multifaceted clinical conditions associated with ageing of the population, the presence of co-morbidities and the need for polypharmacy. The aim of this European Heart Rhythm Association Scientific Initiatives Committee survey was to provide an insight into the role of the Arrhythmia Team, an integrated, multidisciplinary approach to management of patients with cardiac arrhythmias. Forty-eight centres from 18 European countries replied to the Web-based questionnaire. The presence of an Arrhythmia Team was reported by 44% of the respondents, whereas 17% were not familiar with this term. Apart from the electrophysiologist, health professionals who should belong to such teams, according to the majority of the respondents, include a clinical cardiologist, a nurse, a cardiac surgeon, a heart failure specialist, a geneticist, and a geriatrician. Its main activity should be dedicated to the management of patients with complex clinical conditions or refractory or inherited forms of arrhythmias. When present, the Arrhythmia Team was considered helpful by 95% of respondents; the majority of centres (79%) agreed that it should be implemented. The Arrhythmia Team seems to be connected to important expectations in the management of cardiac arrhythmias. The efficacy of such an integrated and multidisciplinary approach should be encouraged and tested in clinical practice. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  10. Biological Rhythms in the Skin.

    Science.gov (United States)

    Matsui, Mary S; Pelle, Edward; Dong, Kelly; Pernodet, Nadine

    2016-05-24

    Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet environmental challenges associated with the solar day. This multi-oscillatory network is entrained by the master pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus, which directs an organism's rhythmic expression of physiological functions and behavior via a hierarchical system. This system has been highly conserved throughout evolution and uses transcriptional-translational autoregulatory loops. This master clock, following environmental cues, regulates an organism's sleep pattern, body temperature, cardiac activity and blood pressure, hormone secretion, oxygen consumption and metabolic rate. Mammalian peripheral clocks and clock gene expression have recently been discovered and are present in all nucleated cells in our body. Like other essential organ of the body, the skin also has cycles that are informed by this master regulator. In addition, skin cells have peripheral clocks that can function autonomously. First described in 2000 for skin, this review summarizes some important aspects of a rapidly growing body of research in circadian and ultradian (an oscillation that repeats multiple times during a 24 h period) cutaneous rhythms, including clock mechanisms, functional manifestations, and stimuli that entrain or disrupt normal cycling. Some specific relationships between disrupted clock signaling and consequences to skin health are discussed in more depth in the other invited articles in this IJMS issue on Sleep, Circadian Rhythm and Skin.

  11. Circadian rhythm and cardiovascular disorders

    Directory of Open Access Journals (Sweden)

    Zhang L

    2014-07-01

    Full Text Available Lilei Zhang,1–3 Mohamed Khaled Sabeh,2,3 Mukesh K Jain2,31Department of Genetics and Genome Sciences, 2Case Cardiovascular Research Institute, Case Western Reserve University, 3Harrington Heart and Vascular Institute, Department of Medicine, University Hospitals at Case Medical Center, Cleveland, OH, USAAbstract: Circadian rhythmicity affects all living organisms on earth. Central and peripheral cellular clocks have the ability to oscillate and be entrained to environmental cues, thus allowing organisms to anticipate and synchronize their physiologic processes and behavior to recurring daily environmental alterations. Disruption of the circadian rhythm in modern life, such as by shift work and jet travel, leads to dyssynchrony of the central and peripheral clocks, and is an independent risk factor for cardiovascular disease and the metabolic syndrome. Aging has also been associated with attenuated cellular rhythmicity. Here we summarize the clinical observations linking cardiovascular health to circadian rhythm. In addition, we discuss recent advances in experimental models for understanding the clock machinery in terms of a variety of physiologic processes within the cardiovascular system. Together, these studies build the foundation for applying our knowledge of circadian biology to the development of novel therapy for cardiovascular disorders.Keywords: circadian rhythm, diurnal variation, cardiovascular

  12. The association of quality of life with potentially remediable disruptions of circadian sleep/activity rhythms in patients with advanced lung cancer

    Directory of Open Access Journals (Sweden)

    Braun Donald P

    2011-05-01

    Full Text Available Abstract Background Cancer patients routinely develop symptoms consistent with profound circadian disruption, which causes circadian disruption diminished quality of life. This study was initiated to determine the relationship between the severity of potentially remediable cancer-associated circadian disruption and quality of life among patients with advanced lung cancer. Methods We concurrently investigated the relationship between the circadian rhythms of 84 advanced lung cancer patients and their quality of life outcomes as measured by the EORTC QLQ C30 and Ferrans and Powers QLI. The robustness and stability of activity/sleep circadian daily rhythms were measured by actigraphy. Fifty three of the patients in the study were starting their definitive therapy following diagnosis and thirty one patients were beginning second-line therapy. Among the patients who failed prior therapy, the median time between completing definitive therapy and baseline actigraphy was 4.3 months, (interquartile range 2.1 to 9.8 months. Results We found that circadian disruption is universal and severe among these patients compared to non-cancer-bearing individuals. We found that each of these patient's EORTC QLQ C30 domain scores revealed a compromised capacity to perform the routine activities of daily life. The severity of several, but not all, EORTC QLQ C30 symptom items correlate strongly with the degree of individual circadian disruption. In addition, the scores of all four Ferrans/Powers QLI domains correlate strongly with the degree of circadian disruption. Although Ferrans/Powers QLI domain scores show that cancer and its treatment spared these patients' emotional and psychological health, the QLI Health/Function domain score revealed high levels of patients' dissatisfaction with their health which is much worse when circadian disruption is severe. Circadian disruption selectively affects specific Quality of Life domains, such as the Ferrans/Powers Health

  13. A roadmap to improve the quality of atrial fibrillation management: proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference.

    Science.gov (United States)

    Kirchhof, Paulus; Breithardt, Günter; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Calvert, Melanie; Christoffels, Vincent; Crijns, Harry; Dobrev, Dobromir; Ellinor, Patrick; Fabritz, Larissa; Fetsch, Thomas; Freedman, S Ben; Gerth, Andrea; Goette, Andreas; Guasch, Eduard; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Haeusler, Karl Georg; Heidbüchel, Hein; Heinrich-Nols, Jutta; Hidden-Lucet, Francoise; Hindricks, Gerd; Juul-Möller, Steen; Kääb, Stefan; Kappenberger, Lukas; Kespohl, Stefanie; Kotecha, Dipak; Lane, Deirdre A; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Münzel, Felix; Nabauer, Michael; Nielsen, Jens C; Oeff, Michael; Oldgren, Jonas; Oto, Ali; Piccini, Jonathan P; Pilmeyer, Art; Potpara, Tatjana; Ravens, Ursula; Reinecke, Holger; Rostock, Thomas; Rustige, Joerg; Savelieva, Irene; Schnabel, Renate; Schotten, Ulrich; Schwichtenberg, Lars; Sinner, Moritz F; Steinbeck, Gerhard; Stoll, Monika; Tavazzi, Luigi; Themistoclakis, Sakis; Tse, Hung Fat; Van Gelder, Isabelle C; Vardas, Panagiotis E; Varpula, Timo; Vincent, Alphons; Werring, David; Willems, Stephan; Ziegler, André; Lip, Gregory Y H; Camm, A John

    2016-01-01

    At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  14. Prevalence and presentation of externalized conductors and electrical abnormalities in Riata defibrillator leads after fluoroscopic screening: report from the Netherlands Heart Rhythm Association Device Advisory Committee.

    Science.gov (United States)

    Theuns, Dominic A M J; Elvan, Arif; de Voogt, Willem; de Cock, Carel C; van Erven, Lieselot; Meine, Mathias

    2012-12-01

    The Riata family of implantable cardioverter-defibrillator (ICD) leads is prone to a specific insulation abrasion characterized by externalization of conductor cables. The objective of this study was to determine the prevalence of externalized conductors and electrical abnormalities in Riata ICD leads by fluoroscopic screening and standard ICD interrogation. All ICD implantation centers were contacted by the Netherlands Heart Rhythm Association Device Advisory Committee to identify all patients with an active Riata ICD lead and to perform fluoroscopic screening of the lead. In addition, the electrical integrity of the lead was assessed. As of March 1, 2012, data for 1029 active Riata leads were available; 47% of these were 8-F Riata and 53% were 7-F Riata ST. Externalized conductors were observed in 147 leads (14.3%). Proportion of externalized conductors was higher in 8-F Riata compared with 7-F Riata ST (21.4% vs 8.0%; Pconductors was 65.3 months. The estimated rates of externalized conductors were 6.9% and 36.6% at 5 and 8 years after implantation, respectively. Of the 147 leads with externalized conductors, 10.9% had abnormal electrical parameters vs 3.5% in nonexternalized leads (Pconductors in Riata leads is significantly high (14.3%) using fluoroscopic screening. The majority of externalized conductors are not detectable with standard ICD interrogation. Screening with fluoroscopy is reasonable.

  15. Cerebrospinal fluid sodium rhythms

    Directory of Open Access Journals (Sweden)

    Johnson Benjamin

    2010-01-01

    Full Text Available Abstract Background Cerebrospinal fluid (CSF sodium levels have been reported to rise during episodic migraine. Since migraine frequently starts in early morning or late afternoon, we hypothesized that natural sodium chronobiology may predispose susceptible persons when extracellular CSF sodium increases. Since no mammalian brain sodium rhythms are known, we designed a study of healthy humans to test if cation rhythms exist in CSF. Methods Lumbar CSF was collected every ten minutes at 0.1 mL/min for 24 h from six healthy participants. CSF sodium and potassium concentrations were measured by ion chromatography, total protein by fluorescent spectrometry, and osmolarity by freezing point depression. We analyzed cation and protein distributions over the 24 h period and spectral and permutation tests to identify significant rhythms. We applied the False Discovery Rate method to adjust significance levels for multiple tests and Spearman correlations to compare sodium fluctuations with potassium, protein, and osmolarity. Results The distribution of sodium varied much more than potassium, and there were statistically significant rhythms at 12 and 1.65 h periods. Curve fitting to the average time course of the mean sodium of all six subjects revealed the lowest sodium levels at 03.20 h and highest at 08.00 h, a second nadir at 09.50 h and a second peak at 18.10 h. Sodium levels were not correlated with potassium or protein concentration, or with osmolarity. Conclusion These CSF rhythms are the first reports of sodium chronobiology in the human nervous system. The results are consistent with our hypothesis that rising levels of extracellular sodium may contribute to the timing of migraine onset. The physiological importance of sodium in the nervous system suggests that these rhythms may have additional repercussions on ultradian functions.

  16. Demonstration of a day-night rhythm in human skeletal muscle oxidative capacity

    Directory of Open Access Journals (Sweden)

    Dirk van Moorsel

    2016-08-01

    Conclusions: Our results suggest that the biological clock drives robust rhythms in human skeletal muscle oxidative metabolism. It is tempting to speculate that disruption of these rhythms contribute to the deterioration of metabolic health associated with circadian misalignment.

  17. Associations between diurnal 24-hour rhythm in ambulatory heart rate variability and the timing and amount of meals during the day shift in rotating shift workers.

    Directory of Open Access Journals (Sweden)

    Takahiro Yoshizaki

    Full Text Available It has not hitherto been clarified whether there is an association between dietary behavior and circadian variation in autonomic nervous system activity among shift workers. This study examines diurnal 24-h rhythm in heart rate variability (HRV and dietary behavior among rotating shift workers, while taking into account the sleep-wake cycle and physical activity. The subjects were 11 female and 2 male nurses or caregivers working in a rotating 2-shift system at a health care facility. All the subjects were asked to undergo 24-h electrocardiograph and step count recordings, and to record the time of each meal and the amounts of each food and beverage consumed. Coarse graining spectral analysis was used for approximately 10-min segments of HRV to derive the total power (TOT: >0.04 Hz of the periodic components and the integrated power of periodic components in the low-frequency (LF: 0.04-0.15 Hz and high-frequency (HF: >0.15 Hz ranges. Then the ratio of HF power to TOT (HF nu and the ratio of LF power to HF power (LF/HF were calculated to assess cardiac vagal tone and cardiac sympathovagal balance, respectively. Single cosinor analysis was used to obtain 24-h period variations in both variables of HRV. Acrophases of HF nu and LF/HF expressed in time since awakening were significantly (p<0.05 delayed for subjects having breakfast at a later time after awakening. Multivariable regression analysis indicated that the timing of breakfast, the ratio of energy intake at dinner to total energy intake, and total energy intake were correlated to the acrophases of HF nu and/or LF/HF. These results suggest that the phase angle between circadian variation in cardiac autonomic nervous system activity and the sleep-wake cycle may be associated with dietary behavior in shift workers.

  18. RHYTHM STRUCTURE IN NEWS READING

    Directory of Open Access Journals (Sweden)

    Lluís Mas Manchón

    2013-06-01

    Full Text Available Rhythm is central to news reading in radio and television programs. This paper proposes a three level structure for rhythm in news discourse. It gives a comprehensive definition of rhythm and types of rhythm. Firstly, the Base Rhythm Structure consists of semantic and pragmatic rhythmic accents, coincident with very specific words. Secondly, these accents are grouped together according to type, frequency and order, thereby configuring three types of “rhythmic units” (the Internal Rhythm Structure: starting, main and end units. A last structure level presents four discursive factors that are very important in integrating the overall time structure of news announcing (the Melodic Rhythm Structure. This integral structure for news announcing rhythm should be further tested in acoustic-experimental studies under the criterion of information transmission efficacy.

  19. Rhythm structure in news reading

    Directory of Open Access Journals (Sweden)

    Lluís Mas Manchón

    2012-12-01

    Full Text Available Rhythm is central to news reading in radio and television programs. This paper proposes a three level structure for rhythm in news discourse. It gives a comprehensive definition of rhythm and types of rhythm. Firstly, the Base Rhythm Structure consists of semantic and pragmatic rhythmic accents, coincident with very specific words. Secondly, these accents are grouped together according to type, frequency and order, thereby configuring three types of “rhythmic units” (the Internal Rhythm Structure: starting, main and end units. A last structure level presents four discursive factors that are very important in integrating the overall time structure of news announcing (the Melodic Rhythm Structure. This integral structure for news announcing rhythm should be further tested in acoustic-experimental studies under the criterion of information transmission efficacy.

  20. Rhythm quantization for transcription

    NARCIS (Netherlands)

    Cemgil, A.T.; Desain, P.W.M.; Kappen, H.J.

    1999-01-01

    Automatic Music Transcription is the extraction of an acceptable notation from performed music. One important task in this problem is rhythm quantization which refers to categorization of note durations. Although quantization of a pure mechanical performance is rather straightforward, the task

  1. Heart Rhythm Society

    Science.gov (United States)

    ... importance of stroke prevention, in easy-to-understand language. Get the AF Patient Brochure Need help finding a specialist? Find physicians around the world who specialize in the treatment of arrhythmias using the Heart Rhythm Society’s searchable directory. Learn More Welcome to the Patient ...

  2. Biological Clocks & Circadian Rhythms

    Science.gov (United States)

    Robertson, Laura; Jones, M. Gail

    2009-01-01

    The study of biological clocks and circadian rhythms is an excellent way to address the inquiry strand in the National Science Education Standards (NSES) (NRC 1996). Students can study these everyday phenomena by designing experiments, gathering and analyzing data, and generating new experiments. As students explore biological clocks and circadian…

  3. Biological and physiological rhythms

    Science.gov (United States)

    Strughold, H.; Hale, H. B.

    1975-01-01

    Circadian rhythms, particularly that of sleep and wakefulness, are discussed. The sleep-wakefulness experiences of astronauts during several space missions are described, and predictions are made for future space activities, including Mars missions, interstellar flight, and life on permanent space stations.

  4. Rhythm Sticks without Music.

    Science.gov (United States)

    Mackin, Rosemary

    2000-01-01

    Provides 11 specific rhythm stick activities for preschoolers and kindergartners to increase children's awareness of basic music theory. Lessons incorporated in these activities include tempo, dynamics, intensity, laterality, and directionality. Lessons also address children's awareness of personal space and improved listening skills. Instructions…

  5. Speech rhythm: a metaphor?

    Science.gov (United States)

    Nolan, Francis; Jeon, Hae-Sung

    2014-12-19

    Is speech rhythmic? In the absence of evidence for a traditional view that languages strive to coordinate either syllables or stress-feet with regular time intervals, we consider the alternative that languages exhibit contrastive rhythm subsisting merely in the alternation of stronger and weaker elements. This is initially plausible, particularly for languages with a steep 'prominence gradient', i.e. a large disparity between stronger and weaker elements; but we point out that alternation is poorly achieved even by a 'stress-timed' language such as English, and, historically, languages have conspicuously failed to adopt simple phonological remedies that would ensure alternation. Languages seem more concerned to allow 'syntagmatic contrast' between successive units and to use durational effects to support linguistic functions than to facilitate rhythm. Furthermore, some languages (e.g. Tamil, Korean) lack the lexical prominence which would most straightforwardly underpin prominence of alternation. We conclude that speech is not incontestibly rhythmic, and may even be antirhythmic. However, its linguistic structure and patterning allow the metaphorical extension of rhythm in varying degrees and in different ways depending on the language, and it is this analogical process which allows speech to be matched to external rhythms. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  6. Visible Battle Rhythm

    Science.gov (United States)

    2006-06-01

    Rhythm tools and methods. 3. Related Work VBR uses the basic principles of Gantt chart design to organize events along a horizontal timeline. This...Coalition operations • Involvement of Civilian Orgs / NGO’s Increased Situational Awareness required © 2006 Oculus Info Inc. COP21 TD 5 Commander’s

  7. Reduction in LFP cross-frequency coupling between theta and gamma rhythms associated with impaired STP and LTP in a rat model of brain ischemia

    Directory of Open Access Journals (Sweden)

    Tao eZhang

    2013-04-01

    Full Text Available The theta-gamma cross-frequency coupling (CFC in hippocampus was reported to reflect memory process. In this study, we measured the CFC of hippocampal local field potentials (LFPs in a two-vessel occlusion (2VO rat model, combined with both amplitude and phase properties and associated with short and long-term plasticity indicating the memory function. Male Wistar rats were used and a 2VO model was established. STP and LTP were recorded in hippocampal CA3-CA1 pathway after LFPs were collected in both CA3 and CA1. Based on the data of relative power spectra and phase synchronization, it suggested that both the amplitude and phase coupling of either theta or gamma rhythm were involved in modulating the neural network in 2VO rats. In order to determine whether the CFC was also implicated in neural impairment in 2VO rats, the coupling of CA3 theta–CA1 gamma was measured by both phase-phase coupling (n:m phase synchronization and phase-amplitude coupling. The attenuated CFC strength in 2VO rats implied the impaired neural communication in the coordination of theta-gamma entraining process. Moreover, compared with modulation index (MI a novel algorithm named cross frequency conditional mutual information (CF-CMI, was developed to focus on the coupling between theta phase and the phase of gamma amplitude. The results suggest that the reduced CFC strength probably attributed to the disruption of the phase of CA1 gamma envelop. In conclusion, it implied that the phase coupling and CFC of hippocampal theta and gamma played an important role in supporting functions of neural network. Furthermore, synaptic plasticity on CA3-CA1 pathway was reduced in line with the decreased CFC strength from CA3 to CA1. It partly supported our hypothesis that directional CFC indicator might probably be used as a measure of synaptic plasticity.

  8. Biological clocks and rhythms in intertidal crustaceans.

    Science.gov (United States)

    de la Iglesia, Horacio O; Hsu, Yun-Wei A

    2010-06-01

    Animals with habitats within the intertidal zone are exposed to environmental cycles that include the ebb and flow of tidal waters, changes in tidal levels associated with the lunar month, the light-dark cycle and the alternation of seasons. This intricate temporal environment results in the selection of biological timing systems with endogenous clocks that can oscillate with this wide range of periodicities. Whereas great progress has been made in our understanding of the molecular and neural bases of circadian rhythms, that is, endogenous rhythms synchronized to the solar day, there is little understanding on how circatidal rhythms, namely endogenous rhythms synchronized to tides, are generated. Intertidal crustaceans have been a pivotal group for the demonstration of the endogenous nature of circatidal rhythms and their mechanisms of entrainment. We review here some of the classic work using intertidal crustaceans to unmask basic properties of circatidal systems, as well as work from our laboratory that aims to identify putative chemical signals that could be involved in the circatidal systems of decapod crustaceans.

  9. Analyzing biological rhythms in clinical trials.

    Science.gov (United States)

    Elkum, Naser B; Myles, James D; Kumar, Pranesh

    2008-09-01

    The human body exhibits a variety of biological rhythms. There are patterns that correspond, among others, to the daily wake / sleep cycle, a yearly seasonal cycle and, in women, the menstrual cycle. Sine/cosine functions are often used to model biological patterns for continuous data, but this model is not appropriate for analysis of biological rhythms in failure time data. We consider a method appropriate for analysis of biological rhythms in clinical trials. We present a method to provide an estimate and confidence interval of the time when the minimum hazard is achieved. A motivating example from a clinical trial of adjuvant of pre-menopausal breast cancer patients provides an important illustration of the methodology in practice. Adapting the Cosinor method to the Weibull proportional hazards model is proposed as useful way of modeling the biological rhythm data. It presents a method to estimate the time that achieves the minimum hazard along with its associated confidence interval. The application of this technique to the breast cancer data revealed that the optimal day for pre-resection incisional or excisional biopsy of 28-day cycle (i.e. the day associated with the lowest recurrence rate) is day 8 with 95% CI 5-10. We found that older age, fewer positive nodes, smaller tumor size, and experimental treatment are important prognostic factors of longer relapse-free survival. The analysis of biological/circadian rhythms is usually handled by Cosinor rhythmometry method. However, in FTD this is simply not possible. In this case, we propose to adapt the Cosinor method to the Weibull proportional hazard model. The advantage of the proposed method is its ability to model survival data. This method is not limited to breast cancer data, and may be applied to any biological rhythms linked to right censored data.

  10. Daily rhythm of cerebral blood flow velocity

    Directory of Open Access Journals (Sweden)

    Spielman Arthur J

    2005-03-01

    Full Text Available Abstract Background CBFV (cerebral blood flow velocity is lower in the morning than in the afternoon and evening. Two hypotheses have been proposed to explain the time of day changes in CBFV: 1 CBFV changes are due to sleep-associated processes or 2 time of day changes in CBFV are due to an endogenous circadian rhythm independent of sleep. The aim of this study was to examine CBFV over 30 hours of sustained wakefulness to determine whether CBFV exhibits fluctuations associated with time of day. Methods Eleven subjects underwent a modified constant routine protocol. CBFV from the middle cerebral artery was monitored by chronic recording of Transcranial Doppler (TCD ultrasonography. Other variables included core body temperature (CBT, end-tidal carbon dioxide (EtCO2, blood pressure, and heart rate. Salivary dim light melatonin onset (DLMO served as a measure of endogenous circadian phase position. Results A non-linear multiple regression, cosine fit analysis revealed that both the CBT and CBFV rhythm fit a 24 hour rhythm (R2 = 0.62 and R2 = 0.68, respectively. Circadian phase position of CBT occurred at 6:05 am while CBFV occurred at 12:02 pm, revealing a six hour, or 90 degree difference between these two rhythms (t = 4.9, df = 10, p Conclusion In conclusion, time of day variations in CBFV have an approximately 24 hour rhythm under constant conditions, suggesting regulation by a circadian oscillator. The 90 degree-phase angle difference between the CBT and CBFV rhythms may help explain previous findings of lower CBFV values in the morning. The phase difference occurs at a time period during which cognitive performance decrements have been observed and when both cardiovascular and cerebrovascular events occur more frequently. The mechanisms underlying this phase angle difference require further exploration.

  11. Circadian rhythms in obsessive-compulsive disorder

    NARCIS (Netherlands)

    Lange, Klaus W.; Lange, Katharina M.; Hauser, Joachim; Tucha, Lara; Tucha, Oliver

    2012-01-01

    The etiopathology and neurobiology of obsessive-compulsive disorder (OCD) are not fully understood. As for altered circadian rhythms associated with OCD, hormonal dysregulation and a delayed sleep phase have come into the focus of research. The novel antidepressant agomelatine is able to

  12. The relationship between bipolar disorder and biological rhythms.

    Science.gov (United States)

    Gonzalez, Robert

    2014-04-01

    Rhythm disruption is a core feature of bipolar disorder and it has been hypothesized that disturbances of the circadian timing system play a fundamental role in the etiology of the disorder. We sought to investigate (1) theoretical models for biological rhythm disruptions in bipolar disorder, (2) physiological disturbances of biological rhythms in bipolar disorder, (3) clinical and therapeutic implications of biological rhythm disturbances in bipolar disorder, and (4) associations between circadian gene variations and bipolar disorder. PubMed database was searched systematically for articles that were published on or before May 5, 2013, and were written in English using the terms bipolar disorder, clock genes, endogenous clock, molecular clock, biological rhythms, circadian, suprachiasmatic nucleus, circadian rhythm, melatonin, and sleep. Seventy-four articles highlighting the objectives were included in the review. Data regarding exploring the association between bipolar disorder and circadian and chronobiological phenomena were reviewed and findings summarized. The literature reviewed suggests that circadian rhythm disturbance may be a feature of bipolar disorder. In toto, the literature suggests that circadian rhythm disturbances may be a feature of bipolar disorder. This area of research has received theoretical consideration as playing a significant role in the pathophysiology of the illness but has been understudied to this point. Further research in the field is warranted. © Copyright 2014 Physicians Postgraduate Press, Inc.

  13. Circadian Rhythms in Cyanobacteria

    Science.gov (United States)

    Golden, Susan S.

    2015-01-01

    SUMMARY Life on earth is subject to daily and predictable fluctuations in light intensity, temperature, and humidity created by rotation of the earth. Circadian rhythms, generated by a circadian clock, control temporal programs of cellular physiology to facilitate adaptation to daily environmental changes. Circadian rhythms are nearly ubiquitous and are found in both prokaryotic and eukaryotic organisms. Here we introduce the molecular mechanism of the circadian clock in the model cyanobacterium Synechococcus elongatus PCC 7942. We review the current understanding of the cyanobacterial clock, emphasizing recent work that has generated a more comprehensive understanding of how the circadian oscillator becomes synchronized with the external environment and how information from the oscillator is transmitted to generate rhythms of biological activity. These results have changed how we think about the clock, shifting away from a linear model to one in which the clock is viewed as an interactive network of multifunctional components that are integrated into the context of the cell in order to pace and reset the oscillator. We conclude with a discussion of how this basic timekeeping mechanism differs in other cyanobacterial species and how information gleaned from work in cyanobacteria can be translated to understanding rhythmic phenomena in other prokaryotic systems. PMID:26335718

  14. Heme-binding characteristics of the isolated PAS-B domain of mouse Per2, a transcriptional regulatory factor associated with circadian rhythms.

    Science.gov (United States)

    Hayasaka, Koya; Kitanishi, Kenichi; Igarashi, Jotaro; Shimizu, Toru

    2011-02-01

    Mouse period homolog 2 (mPer2), an important transcriptional regulatory factor associated with circadian rhythms, is composed of two N-terminal PAS (PAS-A and PAS-B) domains and a C-terminal domain. The PAS-A domain of mPer2 binds the heme iron via a Cys axial ligand. A corresponding transcriptional regulatory factor, neuronal PAS 2 protein (NPAS2), also contains PAS-A and PAS-B domains at the N-terminus with heme-binding capability. In particular, the PAS-B domain appears important for protein-protein interactions critical for transcriptional regulation. In the present study, we examined the heme-binding characteristics of the isolated PAS-B domain of mPer2. Our experiments show that the Fe(III) heme binds the isolated PAS-B domain with a heme to protein stoichiometry of 1:1. The Fe(III) protein complex is suggested to consist of an admixture of 6-coordinated His-bound high-spin and low-spin complexes. Marked pH-dependent spectral changes were observed, in contrast to the spectrum of the Fe(III) bound PAS-A domain of mPer2, which appeared pH-resistant. Treatment with diethylpyrocarbonate abolished the heme-binding ability of this protein, supporting the proposal that His is the axial ligand. Heme dissociation was composed of two phases with rate constants of 4.3 × 10⁻⁴ s⁻¹ (50%) and 4.0 × 10⁻³ s⁻¹ (50%), which were markedly higher than that (1.5 × 10⁻⁷ s⁻¹) of the prototype heme protein, myoglobin. The Soret CD band of the H454A PAS-B mutant was significantly different from those of wild-type and other His mutant proteins, strongly suggesting that His454 is one of the axial ligands for the Fe(III) complex. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Rhythm of digestion: keeping time in the gastrointestinal tract.

    Science.gov (United States)

    Bron, Romke; Furness, John B

    2009-10-01

    1. The best characterized mammalian circadian rhythms follow a light-entrained central master pacemaker in the suprachiasmatic nucleus and are associated with fluctuations in the activities of clock genes, including Clock, Bmal1, Per and Cry, the products of which bind to sequences in the promoters of effector genes. This is the central clock. 2. In the present review, we discuss evidence for an independent, but interacting, gut-associated circadian clock, the peripheral clock, which is entrained by food. 3. Disruption of circadian rhythms is associated with a wide range of pathologies, most prominently metabolism linked, but the effects of disruption of circadian rhythms on the digestive system are less well studied, although also likely to lead to functional consequences. There are clues suggestive of links between gastrointestinal disorders related to inflammation, cancer and motility and disruption of peripheral rhythms. Research aimed at understanding these links is still in its infancy. 4. We also discuss practical aspects of the presence of circadian rhythms in gastrointestinal tissues for researchers related to experimental design, data interpretation and the choice of animal models. 5. There is currently sufficient evidence to suggest that circadian rhythms are important to gut function, metabolism and mucosal defence and that further investigation will uncover connections between disordered rhythms and gastrointestinal malfunction.

  16. Biological rhythms and melatonin in mood disorders and their treatments.

    Science.gov (United States)

    Lanfumey, Laurence; Mongeau, Raymond; Hamon, Michel

    2013-05-01

    Affective disorders such as major depression, bipolar disorders and seasonal affective disorders have been described as alterations of various neuronal systems. In addition to the classical monoaminergic hypotheses that have been long proposed to explain the pathophysiology of these disorders, a strong association between circadian rhythms and mood regulation has been suggested in the light of several clinical and preclinical findings. In this review, we summarize the different hypotheses on pathophysiology mechanisms underlying depressive disorders and put a special emphasis on the alterations of melatonin secretion and associated changes in biological rhythms that characterize mood disorders. Causal relationships between alterations in circadian rhythms and mood disorders are strongly supported by the antidepressant efficacy of innovative pharmacological treatments aimed at resynchronizing endogenous rhythms in depressed patients. Genetic, epigenetic and environmental factors generating desynchronization between endogenous biological rhythms and exogenous rhythms driven by environmental and societal constraints are very probably involved in the vulnerability to mood disorders. Further investigations of the molecular/cellular bases of the relationships between stress axis dysfunctions, endogenous biological rhythm dysregulations and associated functional and anatomical brain alterations should allow important progress in the knowledge of pathophysiological mechanisms of affective disorders and the downstream development of innovative, more effective and better tolerated, therapies. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Light Rhythms in Architecture

    DEFF Research Database (Denmark)

    Bülow, Katja

    2013-01-01

    formation and rhythm. When integrated into an architectural concept, electrical lighting non-intended for poetic composition has the ability to contribute to place, time, and function-telling aspects of places in urban contexts. Urban environments are information wise challenging to pre-historic human......On one hand, urban lighting expresses itself in a complex visual environment made by the interplay by between many separate lighting schemes, as street lighting, shop lighting, luminous commercials etc. On the other, a noticeable order of patterns occurs, when lighting is observed as luminous...

  18. The Psychophysics of Brain Rhythms

    Directory of Open Access Journals (Sweden)

    Rufin eVanrullen

    2011-08-01

    Full Text Available It is becoming increasingly apparent that brain oscillations in various frequency bands play important roles in perceptual and attentional processes. Understandably, most of the associated experimental evidence comes from human or animal electrophysiological studies, allowing direct access to the oscillatory activities. However, such periodicities in perception and attention should, in theory, also be observable using the proper psychophysical tools. Here, we review a number of psychophysical techniques that have been used by us and other authors, in successful and sometimes unsuccessful attempts, to reveal the rhythmic nature of perceptual and attentional processes. We argue that the two existing and largely distinct debates about discrete vs. continuous perception and parallel vs. sequential attention should in fact be regarded as two facets of the same question: how do brain rhythms shape the psychological operations of perception and attention?

  19. Neural responses to complex auditory rhythms: the role of attending

    Directory of Open Access Journals (Sweden)

    Heather L Chapin

    2010-12-01

    Full Text Available The aim of this study was to explore the role of attention in pulse and meter perception using complex rhythms. We used a selective attention paradigm in which participants attended to either a complex auditory rhythm or a visually presented word list. Performance on a reproduction task was used to gauge whether participants were attending to the appropriate stimulus. We hypothesized that attention to complex rhythms – which contain no energy at the pulse frequency – would lead to activations in motor areas involved in pulse perception. Moreover, because multiple repetitions of a complex rhythm are needed to perceive a pulse, activations in pulse related areas would be seen only after sufficient time had elapsed for pulse perception to develop. Selective attention was also expected to modulate activity in sensory areas specific to the modality. We found that selective attention to rhythms led to increased BOLD responses in basal ganglia, and basal ganglia activity was observed only after the rhythms had cycled enough times for a stable pulse percept to develop. These observations suggest that attention is needed to recruit motor activations associated with the perception of pulse in complex rhythms. Moreover, attention to the auditory stimulus enhanced activity in an attentional sensory network including primary auditory, insula, anterior cingulate, and prefrontal cortex, and suppressed activity in sensory areas associated with attending to the visual stimulus.

  20. Strange musical rhythms.

    Science.gov (United States)

    Valentinuzzi, Max E; Hortt, Federico

    2014-01-01

    Music, along with its attached rhythm, has been with man for centuries, developing and evolving along with him. Its influence on human behavior and mood can reach levels whose limits are still unknown, especially in everything related to perception, where the whole nervous system is involved. Thus, physiology and psychology become strongly connected areas, while technology, through, for example, the production of music by electronic means, appears as a new unexpected ingredient that traditional composers and musicians of older times could not imagine. Obviously, bioengineering and its multiple branches are not absent either [1]?[4]. The literature is enormous with several specialized journals. When one looks back in time at the evolution of this complex area, the appearance of some kind of sudden jump (as a step function), which took place within a relatively recent short interval, is evident: music is now much more than what it used to be, and rhythm has made a step forward as if resurrecting and renewing the ancient Indian or African drums.

  1. Circannual rhythm of plasmatic vitamin D levels and the association with markers of psychophysical stress in a cohort of Italian professional soccer players.

    Science.gov (United States)

    Lombardi, Giovanni; Vitale, Jacopo Antonino; Logoluso, Sergio; Logoluso, Giovanni; Cocco, Nino; Cocco, Giulio; Cocco, Antonino; Banfi, Giuseppe

    2017-01-01

    Adequate plasmatic Vitamin D levels are crucial to maintain calcium homeostasis and bone metabolism both in the general population and in athletes. Correct dietary supply and a regular sun exposure are fundamental for allowing the desired and effective fitness level. Past studies highlighted a scenario of Vitamin D insufficiency among professional soccer players in several countries, especially in North Europe, whilst a real deficiency in athletes is rare. The typical seasonal fluctuations of Vitamin D are wrongly described transversally in athletes belonging to teams that play at different latitudes and a chronobiologic approach studying the Vitamin D circannual rhythm in soccer players has not been described yet. Therefore, we studied plasma vitamin D, cortisol, testosterone, and creatin kinase (CK) concentrations in three different Italian professional teams training at the same latitude during a period of two consecutive competitive seasons (2013 and 2014). In this retrospective observational study, 167 professional soccer players were recruited (mean age at sampling 25.1 ± 4.7 years) and a total of 667 blood drawings were carried out to determine plasma 25(OH)D, serum cortisol, serum testosterone and CK levels. Testosterone to cortisol ratio (TC) was calculated based as a surrogate marker of overtraining and psychophysical stress and each athlete was drawn until a maximum of 5 times per season. Data extracted by a subgroup of players that underwent at least 4 sample drawings along a year (N = 45) were processed with the single and population mean cosinor tests to evaluate the presence of circannual rhythms: the amplitude (A), acrophase (Φ) and the MESOR (M) are described. In total, 55 players (32.9%) had an insufficient level of 25(OH)D during the seasons and other 15 athletes (9.0%) showed, at least once, a deficiency status of Vitamin D. The rhythmometric analyses applied to the data of Vitamin D revealed the presence of a significant circannual rhythm (p

  2. Serial binary interval ratios improve rhythm reproduction

    OpenAIRE

    Xiang eWu; Anders eWestanmo; Liang eZhou; Junhao ePan

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are bett...

  3. Music and rhythm in physiotherapy

    OpenAIRE

    Císařová, Romana

    2010-01-01

    This bachelor work is analyzing use of music and rhythm in physiotherapy practice. It describes effects of music on somatic functions and psychology of a man. It emphasizes significance of rhythm and rhythmical activities during the therapy. Focuses on therapy application in to the neurology, pediatrics and for patients suffering psychical problems.

  4. Systems biology of cellular rhythms.

    Science.gov (United States)

    Goldbeter, A; Gérard, C; Gonze, D; Leloup, J-C; Dupont, G

    2012-08-31

    Rhythms abound in biological systems, particularly at the cellular level where they originate from the feedback loops present in regulatory networks. Cellular rhythms can be investigated both by experimental and modeling approaches, and thus represent a prototypic field of research for systems biology. They have also become a major topic in synthetic biology. We review advances in the study of cellular rhythms of biochemical rather than electrical origin by considering a variety of oscillatory processes such as Ca++ oscillations, circadian rhythms, the segmentation clock, oscillations in p53 and NF-κB, synthetic oscillators, and the oscillatory dynamics of cyclin-dependent kinases driving the cell cycle. Finally we discuss the coupling between cellular rhythms and their robustness with respect to molecular noise.

  5. [Circadian rhythms and systems biology].

    Science.gov (United States)

    Goldbeter, Albert; Gérard, Claude; Leloup, Jean-Christophe

    2010-01-01

    Cellular rhythms represent a field of choice for studies in system biology. The examples of circadian rhythms and of the cell cycle show how the experimental and modeling approaches contribute to clarify the conditions in which periodic behavior spontaneously arises in regulatory networks at the cellular level. Circadian rhythms originate from intertwined positive and negative feedback loops controlling the expression of several clock genes. Models can be used to address the dynamical bases of physiological disorders related to dysfunctions of the mammalian circadian clock. The cell cycle is driven by a network of cyclin-dependent kinases (Cdks). Modeled in the form of four modules coupled through multiple regulatory interactions, the Cdk network operates in an oscillatory manner in the presence of sufficient amounts of growth factor. For circadian rhythms and the cell cycle, as for other recently observed cellular rhythms, periodic behavior represents an emergent property of biological systems related to their regulatory structure.

  6. [Semi-automatic defibrillators does not always interpret heart rhythms correctly. Five patients were defibrillated despite non-shockable rhythms].

    Science.gov (United States)

    Wangenheim, Burkard; Israelsson, Johan; Lindstaedt, Michael; Carlsson, Jörg

    2015-08-04

    Automated external defibrillators (AED) have become an important part of the »the chain of survival« in case of sudden cardiac arrest (SCA), where early defibrillation is lifesaving. The American Heart Association demands that AEDs have a specificity of >99 % to recognize normal sinus rhythm and >95 % for the other non-shockable rhythms. Reports on their performance in the field are scarce. We present five cases in which AED recommended shock for apparently non-shockable rhythms. This indicates the necessity to systematically reevaluate AED performance.

  7. Cognitive deficit is associated with phase advance of sleep-wake rhythm, daily napping, and prolonged sleep duration--a cross-sectional study in 2,947 community-dwelling older adults.

    Science.gov (United States)

    Auyeung, Tung Wai; Lee, Jenny Shun Wah; Leung, Jason; Kwok, Timothy; Leung, Ping Chung; Woo, Jean; Wing, Yun Kwok

    2013-04-01

    This study aims to examine the phase advance of sleep-wake rhythm, napping habit, nocturnal sleep duration, prolonged sleep latency and insomnia and their relationship with cognitive function. This is a cross-sectional study. Participants in this study are 2,947 community-dwelling adults older than 65 years old. Measurements of mini-mental examination (MMSE) score, go-to-bed time, wake-up time, nocturnal sleep duration, prolonged sleep latency, napping, and insomnia were done. The mean (standard deviation) nocturnal sleep hours was 7.96 (1.39) h. Twenty-one percent and 16.2% of the participants complained of prolonged sleep latency longer than 1 h and insomnia, respectively. Fifty-six percent of the participants napped once or more than once weekly. With advancing age, the participants reported longer sleep duration (pnapping frequency, p for tend 0.026.The MMSE score decreased when the sleep duration prolonged from 7 h to ≧10 h (p for trend 0.006). No trend was observed from the sleep duration <4 up to 7.9 h (p for trend 0.500). Modest age-independent phase advance of the sleep-wake rhythm is associated with lower cognitive function. Whether this is a manifestation of early pre-clinical dementia and whether its recognition with early stabilization can slow cognitive decline remain elusive.

  8. Gamma Rhythms and Beta Rhythms Have Different Synchronization Properties

    National Research Council Canada - National Science Library

    N. Kopell; G. B. Ermentrout; M. A. Whittington; R. D. Traub

    2000-01-01

    ...) have a different dynamical structure than that of gamma (30-70 Hz). We use a simplified model to show that the different rhythms employ different dynamical mechanisms to synchronize, based on different ionic currents...

  9. Looking for Rhythm in Speech

    OpenAIRE

    Fred Cummins

    2012-01-01

    A brief review is provided of the study of rhythm in speech. Much of that activity has focused on looking for empirical measures that would support the categorization of languages into discrete rhythm ‘types’. That activity has had little success, and has used the term ‘rhythm’ in increasingly unmusical and unintuitive ways. Recent approaches to conversation that regard speech as a whole-body activity are found to provide considerations of rhythm that are closer to the central, musical, sense...

  10. Looking for Rhythm in Speech

    Directory of Open Access Journals (Sweden)

    Fred Cummins

    2012-09-01

    Full Text Available A brief review is provided of the study of rhythm in speech. Much of that activity has focused on looking for empirical measures that would support the categorization of languages into discrete rhythm ‘types’. That activity has had little success, and has used the term ‘rhythm’ in increasingly unmusical and unintuitive ways. Recent approaches to conversation that regard speech as a whole-body activity are found to provide considerations of rhythm that are closer to the central, musical, sense of the term.

  11. Statistics for Sleep and Biological Rhythms Research.

    Science.gov (United States)

    Bianchi, Matt T; Phillips, Andrew J K; Wang, Wei; Klerman, Elizabeth B

    2017-02-01

    The Journal of Biological Rhythms will be publishing articles exploring analysis and statistical topics relevant to researchers in biological rhythms and sleep research. The goal is to provide an overview of the most common issues that arise in the analysis and interpretation of data in these fields. By using case examples and highlighting the pearls and pitfalls of statistical inference, the authors will identify and explain ways in which experimental scientists can avoid common analytical and statistical mistakes and use appropriate analytical and statistical methods in their research. In this first article, we address the first steps in analysis of data: understanding the underlying statistical distribution of the data and establishing associative versus causal relationships. These ideas are then applied to sample size, power calculations, correlation testing, differences between description and prediction, and the narrative fallacy.

  12. Sleep, circadian rhythms, and athletic performance.

    Science.gov (United States)

    Thun, Eirunn; Bjorvatn, Bjørn; Flo, Elisabeth; Harris, Anette; Pallesen, Ståle

    2015-10-01

    Sleep deprivation and time of day are both known to influence performance. A growing body of research has focused on how sleep and circadian rhythms impact athletic performance. This review provides a systematic overview of this research. We searched three different databases for articles on these issues and inspected relevant reference lists. In all, 113 articles met our inclusion criteria. The most robust result is that athletic performance seems to be best in the evening around the time when the core body temperature typically is at its peak. Sleep deprivation was negatively associated with performance whereas sleep extension seems to improve performance. The effects of desynchronization of circadian rhythms depend on the local time at which performance occurs. The review includes a discussion of differences regarding types of skills involved as well as methodological issues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Circadian Rhythm Management System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The value of measuring sleep-wake cycles is significantly enhanced by measuring other physiological signals that depend on circadian rhythms (such as heart rate and...

  14. Learning by joining the Rhythm

    DEFF Research Database (Denmark)

    Lund, Ole

    2012-01-01

    This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double scull together....... The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However, Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm......, which will enable the rowers to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s finely tuned sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood...

  15. Learning by joining the Rhythm

    DEFF Research Database (Denmark)

    Lund, Ole

    2012-01-01

    . The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However, Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm......, which will enable the rowers to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s finely tuned sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood......This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double scull together...

  16. Substances and Heart Rhythm Disorders

    Science.gov (United States)

    ... good” cholesterol (HDL cholesterol). But for some people, alcohol can cause heart rhythm disturbances. Alcohol abuse is a major risk factor for High Blood Pressure , cardiomyopathy (weak heart muscle), heart failure and stroke . Tobacco Tobacco (cigarettes) ...

  17. Learning by joining the Rhythm

    DEFF Research Database (Denmark)

    Lund, Ole

    2012-01-01

    This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double scull together......, which will enable the rowers to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s finely tuned sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood....... The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However, Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm...

  18. Learning by joining the rhythm

    DEFF Research Database (Denmark)

    Lund, Ole; Ravn, Susanne; Christensen, Mette Krogh

    2012-01-01

    This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double sculler together......, to be able to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s fine-grained sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood as an embodied....... The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm...

  19. Modeling biological rhythms in failure time data

    Directory of Open Access Journals (Sweden)

    Myles James D

    2006-11-01

    Full Text Available Abstract Background The human body exhibits a variety of biological rhythms. There are patterns that correspond, among others, to the daily wake/sleep cycle, a yearly seasonal cycle and, in women, the menstrual cycle. Sine/cosine functions are often used to model biological patterns for continuous data, but this model is not appropriate for analysis of biological rhythms in failure time data. Methods We adapt the cosinor method to the proportional hazards model and present a method to provide an estimate and confidence interval of the time when the minimum hazard is achieved. We then apply this model to data taken from a clinical trial of adjuvant of pre-menopausal breast cancer patients. Results The application of this technique to the breast cancer data revealed that the optimal day for pre-resection incisional or excisional biopsy of 28-day cycle (i. e. the day associated with the lowest recurrence rate is day 8 with 95% confidence interval of 4–12 days. We found that older age, fewer positive nodes, smaller tumor size, and experimental treatment were predictive of longer relapse-free survival. Conclusion In this paper we have described a method for modeling failure time data with an underlying biological rhythm. The advantage of adapting a cosinor model to proportional hazards model is its ability to model right censored data. We have presented a method to provide an estimate and confidence interval of the day in the menstrual cycle where the minimum hazard is achieved. This method is not limited to breast cancer data, and may be applied to any biological rhythms linked to right censored data.

  20. Self-sustained circadian rhythm in cultured human mononuclear cells isolated from peripheral blood.

    Science.gov (United States)

    Ebisawa, Takashi; Numazawa, Kahori; Shimada, Hiroko; Izutsu, Hiroyuki; Sasaki, Tsukasa; Kato, Nobumasa; Tokunaga, Katsushi; Mori, Akio; Honma, Ken-ichi; Honma, Sato; Shibata, Shigenobu

    2010-02-01

    Disturbed circadian rhythmicity is associated with human diseases such as sleep and mood disorders. However, study of human endogenous circadian rhythm is laborious and time-consuming, which hampers the elucidation of diseases. It has been reported that peripheral tissues exhibit circadian rhythmicity as the suprachiasmatic nucleus-the center of the biological clock. We tried to study human circadian rhythm using cultured peripheral blood mononuclear cells (PBMCs) obtained from a single collection of venous blood. Activated human PBMCs showed self-sustained circadian rhythm of clock gene expression, which indicates that they are useful for investigating human endogenous circadian rhythm.

  1. Treatment of Atrial Fibrillation and Concordance With the American Heart Association/American College of Cardiology/Heart Rhythm Society Guidelines: Findings From ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation).

    Science.gov (United States)

    Barnett, Adam S; Kim, Sunghee; Fonarow, Gregg C; Thomas, Laine E; Reiffel, James A; Allen, Larry A; Freeman, James V; Naccarelli, Gerald; Mahaffey, Kenneth W; Go, Alan S; Kowey, Peter R; Ansell, Jack E; Gersh, Bernard J; Hylek, Elaine M; Peterson, Eric D; Piccini, Jonathan P

    2017-11-01

    It is unclear how frequently patients with atrial fibrillation receive guideline-concordant (GC) care and whether guideline concordance is associated with improved outcomes. Using data from ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation), we determined how frequently patients received care that was concordant with 11 recommendations from the 2014 American Heart Association/American College of Cardiology/Heart Rhythm Society atrial fibrillation guidelines pertaining to antithrombotic therapy, rate control, and antiarrhythmic medications. We also analyzed the association between GC care and clinical outcomes at both the patient level and center level. A total of 9570 patients were included. The median age was 75 years (interquartile range, 67-82), and the median CHA2DS2-VASc score was 4 (interquartile range, 3-5). A total of 5977 patients (62.5%) received care that was concordant with all guideline recommendations for which they were eligible. Rates of GC care were higher in patients treated by providers with greater specialization in arrhythmias (60.0%, 62.4%, and 67.0% for primary care physicians, cardiologists, and electrophysiologists, respectively; Passociation between GC care and improved risk-adjusted outcomes. © 2017 American Heart Association, Inc.

  2. Comparison of English Language Rhythm and Kalhori Kurdish Language Rhythm

    Directory of Open Access Journals (Sweden)

    Nafiseh Taghva

    2016-04-01

    Full Text Available Investigating on quantitative features of languages rhythm is a recent issue that attracts the attention of linguists. Interval-based method is a method of studying the rhythmic quantitative features of languages. This method use Pairwise Variability Index (PVI to consider the variability of vocalic duration and inter-vocalic duration of sentences which leads to classification of languages rhythm into stress-timed languages and syllable-timed ones. This study aims to consider the rhythm of British English and Kalhori Kurdish, which is spoken in some part of west of Iran, based on interval-based method. In order to reach this aim the duration variability of vocalic interval and inter-vocalic interval of English and Kalhori Kurdish are measured by PVI. Afterward the outcomes of this study were compared to the existed results of other languages. The results of this research demonstrated that the rhythmic quantitative features of these two languages are placed among stress-timed languages.   Keywords: Rhythm, interval-based method, syllable-timed, stress-timed

  3. Rhythms and Dance. Games of Low Organization.

    Science.gov (United States)

    Montgomery County Public Schools, Rockville, MD.

    This guide provides activities, resources, and ideas for elementary physical education and classroom teachers. The activities in the basic rhythms program are divided into five classifications: movement patterns, dramatic activities, singing games, creative rhythms-dance, and rhythmic gymnastics. At the beginning of the basic rhythms sections is a…

  4. Circadian rhythms in mitochondrial respiration

    NARCIS (Netherlands)

    de Goede, Paul; Wefers, Jakob; Brombacher, Eline Constance; Schrauwen, P.; Kalsbeek, Andries

    2018-01-01

    Many physiological processes are regulated with a 24h periodicity to anticipate the environmental changes of day to nighttime and vice versa. These 24h regulations, commonly termed circadian rhythms, amongst others control the sleep-wake cycle, locomotor activity and preparation for food

  5. Mood disorders and biological rhythms in young adults: A large population-based study.

    Science.gov (United States)

    Mondin, Thaíse Campos; Cardoso, Taiane de Azevedo; Souza, Luciano Dias de Mattos; Jansen, Karen; da Silva Magalhães, Pedro Vieira; Kapczinski, Flávio; da Silva, Ricardo Azevedo

    2017-01-01

    It is known that sleep disturbance has been considered a trait-marker of mood disorders. However, the role of disruptions in biological rhythms, such as eating, activity, and social patterns, needs to be better understood. To assess the differences in biological rhythms in subjects with bipolar disorder, major depressive disorder, and healthy controls. We also tested the association between disruptions of biological rhythms and circadian preferences. A cross-sectional, population-based study with a representative sample of 1023 young adults. Bipolar disorder and depression were diagnosed using The Mini International Neuropsychiatric Interview - PLUS and DSM Structured Clinical Interview. Self-reported biological rhythms and circadian preference were assessed using the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN). Bipolar disorders and depression subjects presented higher rates of disruption in biological rhythms when compared to healthy controls even after adjusting for sex, socioeconomic status, alcohol, tobacco, illicit drug use, anxiety disorder and psychotropic medication use. Euthymic subjects showed higher biological rhythm disruption when compared to controls. Higher disruption in biological rhythms was observed in subjects with evening preferences. Higher disruption in biological rhythms occurs in individuals with depression and bipolar disorder even on periods of euthymia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Normalizing effect of bright light therapy on temperature circadian rhythm in patients with eating disorders.

    Science.gov (United States)

    Yamamotová, Anna; Papezová, Hana; Vevera, Jan

    2008-02-01

    Light and food are important synchronizers of circadian rhythmicity. In eating disorders, the circadian rhythms of food intake and temperature are abnormal. We analyzed the effect of the morning light application on the circadian rhythm of tympanic temperature and its association with hunger and mood changes in the sample of 25 female patients hospitalized with DSM-IV diagnosis of eating disorders (14 bulimia nervosa and 11 anorexia nervosa) and in 6 healthy women. Light therapy reduced interindividual variability of the temperature acrophase, synchronized the temperature and hunger rhythms and showed an antidepressant effect on patients with eating disorders. Bright light therapy normalized the circadian rhythm of body temperature in both anorexic and bulimic patients: phase advanced rhythm was delayed and phase delayed rhythm was advanced. In contrast with anorexic patients, the majority of bulimic patients had normal temperature rhythm before the therapy and this rhythm was not changed by the therapy. The light therapy normalized temperature circadian rhythm in patient with eating disorders. We hypothesize that the light therapy can also contribute to improvement of pathological eating pattern because of the functional connections between light and food entrained oscillators. The light may help to restore the irregular circadian rhythmicity induced by chaotic food intake.

  7. Glucocorticoids play a key role in circadian cell cycle rhythms.

    Directory of Open Access Journals (Sweden)

    Thomas Dickmeis

    2007-04-01

    Full Text Available Clock output pathways play a pivotal role by relaying timing information from the circadian clock to a diversity of physiological systems. Both cell-autonomous and systemic mechanisms have been implicated as clock outputs; however, the relative importance and interplay between these mechanisms are poorly understood. The cell cycle represents a highly conserved regulatory target of the circadian timing system. Previously, we have demonstrated that in zebrafish, the circadian clock has the capacity to generate daily rhythms of S phase by a cell-autonomous mechanism in vitro. Here, by studying a panel of zebrafish mutants, we reveal that the pituitary-adrenal axis also plays an essential role in establishing these rhythms in the whole animal. Mutants with a reduction or a complete absence of corticotrope pituitary cells show attenuated cell-proliferation rhythms, whereas expression of circadian clock genes is not affected. We show that the corticotrope deficiency is associated with reduced cortisol levels, implicating glucocorticoids as a component of a systemic signaling pathway required for circadian cell cycle rhythmicity. Strikingly, high-amplitude rhythms can be rescued by exposing mutant larvae to a tonic concentration of a glucocorticoid agonist. Our work suggests that cell-autonomous clock mechanisms are not sufficient to establish circadian cell cycle rhythms at the whole-animal level. Instead, they act in concert with a systemic signaling environment of which glucocorticoids are an essential part.

  8. [Heart rhythm abnormalities in middle-aged veteran elite athletes].

    Science.gov (United States)

    Sharashdze, N S; Pagava, Z T; Saatashvili, G A; Agladze, R A

    2008-06-01

    Disrrhythmia is frequent finding in high competitive athletes. Majority of heart rhythm abnormalities in athletes, suggested being benign, however, prognostic value of it is not yet well established. Purpose of the present study was to investigate heart rhythm and relationship of heart rhythm abnormalities with LV mass in veteran elite athletes. 30 veteran elite athletes (16 soccer players and 14 water-polo players) aged 30-50 were studied. They formed main group. >10 years of active sports activity and >5 years after competitive sports cessation. All athletes were symptom free. Control group consists of 30 age - matched sedentary healthy individuals. In all study subjects ambulatory 24 hour ECG was recorded and, LV mass, dimensions and function by ultrasound-Doppler technique was evaluated. LV mass by Devereux formula was calculated and indexed to body surface area. Student's t-test for continuous variables, Descriptive statistics and Fisher's exact test for categorical variables were used. A P-value of conductivity abnormalities as well as complex arrhythmias were more frequent findings in athletes as compared with healthy sedentary subjects. Heart Rhythm abnormalities were associated with enhanced LV mass in Veteran athletes. Hence, veteran elite athletes may be at increased risk of life threatening arrhythmias. However, prognostic value of heart rhythm disturbances in veteran athletes has to be studied.

  9. Are different rhythms good for different functions?

    Directory of Open Access Journals (Sweden)

    Nancy Kopell

    2010-11-01

    Full Text Available This essay discusses the relationship between the physiology of rhythmsand potential functional roles. We focus on how the biophysics underlyingdifferent rhythms can give rise to different abilities of a network toform and manipulate cell assemblies. We also discuss how changes in themodulatory setting of the rhythms can change the flow of informationthrough cortical circuits, again tying physiology to computation. Wesuggest that diverse rhythms, or variations of a rhythm, can supportdifferent components of a cognitive act, with multiple rhythms potentiallyplaying multiple roles.

  10. Novel oral anticoagulants for stroke prevention in atrial fibrillation

    DEFF Research Database (Denmark)

    Lip, Gregory Y H; Bongiorni, Maria Grazia; Dobreanu, Dan

    2013-01-01

    The purpose of this European Heart Rhythm Association (EHRA) survey was to assess clinical practice in relation to stroke prevention in atrial fibrillation (AF), particularly into the use of novel oral anticoagulants (NOACs) for stroke prevention, among members of the EHRA electrophysiology (EP......) research network. In this EP Wire survey, we have provided some insights into current practice in Europe for the use of NOACs for stroke prevention in AF. There were clear practice differences evident, and also the need for greater adherence to the guidelines, especially since guideline adherent management...

  11. PR Interval Associated Genes, Atrial Remodeling and Rhythm Outcome of Catheter Ablation of Atrial Fibrillation—A Gene-Based Analysis of GWAS Data

    Directory of Open Access Journals (Sweden)

    Daniela Husser

    2017-12-01

    Full Text Available Background: PR interval prolongation has recently been shown to associate with advanced left atrial remodeling and atrial fibrillation (AF recurrence after catheter ablation. While different genome-wide association studies (GWAS have implicated 13 loci to associate with the PR interval as an AF endophenotype their subsequent associations with AF remodeling and response to catheter ablation are unknown. Here, we perform a gene-based analysis of GWAS data to test the hypothesis that PR interval candidate genes also associate with left atrial remodeling and arrhythmia recurrence following AF catheter ablation.Methods and Results: Samples from 660 patients with paroxysmal (n = 370 or persistent AF (n = 290 undergoing AF catheter ablation were genotyped for ~1,000,000 SNPs. Gene-based association was investigated using VEGAS (versatile gene-based association study. Among the 13 candidate genes, SLC8A1, MEIS1, ITGA9, SCN5A, and SOX5 associated with the PR interval. Of those, ITGA9 and SOX5 were significantly associated with left atrial low voltage areas and left atrial diameter and subsequently with AF recurrence after radiofrequency catheter ablation.Conclusion: This study suggests contributions of ITGA9 and SOX5 to AF remodeling expressed as PR interval prolongation, low voltage areas and left atrial dilatation and subsequently to response to catheter ablation. Future and larger studies are necessary to replicate and apply these findings with the aim of designing AF pathophysiology-based multi-locus risk scores.

  12. How Two Players Negotiate Rhythm in a Shared Rhythm Game

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

    2012-01-01

    In a design and working prototype of a shared music interface eleven teams of two people were to collaborate about filling in holes with tones and beats in an evolving ground rhythm. The hypothesis was that users would tune into each other and have sections of characteristic rhythmical relationsh......In a design and working prototype of a shared music interface eleven teams of two people were to collaborate about filling in holes with tones and beats in an evolving ground rhythm. The hypothesis was that users would tune into each other and have sections of characteristic rhythmical...... from each other. Video analysis of user interaction shines light upon how users engaged in a rhythmical relationship, and interviews give information about the user experience in terms of the game play and user collaboration. Based on the findings in this paper we propose design guidelines...... for collaborative rhythmical game play....

  13. Latitudinal clines: an evolutionary view on biological rhythms.

    Science.gov (United States)

    Hut, Roelof A; Paolucci, Silvia; Dor, Roi; Kyriacou, Charalambos P; Daan, Serge

    2013-08-22

    Properties of the circadian and annual timing systems are expected to vary systematically with latitude on the basis of different annual light and temperature patterns at higher latitudes, creating specific selection pressures. We review literature with respect to latitudinal clines in circadian phenotypes as well as in polymorphisms of circadian clock genes and their possible association with annual timing. The use of latitudinal (and altitudinal) clines in identifying selective forces acting on biological rhythms is discussed, and we evaluate how these studies can reveal novel molecular and physiological components of these rhythms.

  14. Analysing Biological Rhythms in Fibromyalgia Syndrome.

    Science.gov (United States)

    Ucar, M; Sarp, Ü; Gül, A I; Tanik, N; Yetisgin, A; Arik, H O; Nas, O; Yılmaz, Y K

    2015-06-01

    This study evaluated biological rhythm disorders in patients with fibromyalgia syndrome (FMS). The study enrolled 82 patients with FMS and 82 controls. Pain intensity was evaluated using a visual analogue scale (VAS). The psychological conditions of the patients were evaluated using the Beck Depression Inventory (BDI). The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) was used to assess disturbances in biological rhythms (ie sleep, activity, social and eating patterns). There was no difference between the two groups at baseline (all p > 0.05). The BDI, BRIAN total, sleep, activity, social, and eating scores were higher in patients with FMS than in the controls (all p biological rhythms and BDI scores (p biological rhythm disturbances in FMS. There is an important relationship between rhythm disorders and FMS. The disturbances in sleep, functional activities, social participation, and disordered rhythms like eating patterns show the need for a multidisciplinary approach to treating patients with FMS.

  15. [Biological rhythms for anaesthesia and intensive care].

    Science.gov (United States)

    Dispersyn, G; Chassard, D; Pain, L

    2010-06-01

    Knowledge of biological rhythms has led to better understanding of the time-of-day dependent effects of anaesthetic drugs. These chronopharmacological effects are currently explained by the biological rhythms modulating the pharmacokinetic, toxic and pharmacodynamic parameters of these substances. Such effect has been described for general anesthetics, local anaesthetics, analgesics as well as for antibiotics. But recent data also highlight that general anaesthetics, probably part of their brain effects, also alter the regulation of biological rhythms, including the sleep-wake or the endogenous circadian temperature rhythms. This desynchronization of biological rhythms can led to disturbance of the circadian secretion of many substances, including hormones. Finally, biological rhythms have been also described with regard to physiology of pain and cardiovascular physiopathology. The concept of biological rhythm should be present in mind not only for the clinical management of patients but also for setting studies in the field of anaesthesia, pain and intensive care. 2010. Published by Elsevier SAS.

  16. Staged hybrid ablation for persistent and longstanding persistent atrial fibrillation effectively restores sinus rhythm in long-term observation.

    Science.gov (United States)

    Zembala, Michal; Filipiak, Krzysztof; Kowalski, Oskar; Buchta, Piotr; Niklewski, Tomasz; Nadziakiewicz, Pawel; Koba, Rafał; Gąsior, Mariusz; Kalarus, Zbigniew; Zembala, Marian

    2017-02-01

    Hybrid ablation (HABL) of atrial fibrillation combining endoscopic, minimally invasive, closed chest epicardial ablation with endocardial CARTO-guided accuracy was introduced to overcome the limitations of current therapeutic options for patients with persistent (PSAF) and longstanding persistent atrial fibrillation (LSPAF). The purpose of this study was to evaluate the procedural safety and feasibility as well as effectiveness of HABL in patients with PSAF and LSPAF 1 year after the procedure. The study is a single-center, prospective clinical registry. From 07/2009 to 12.2014, 90 patients with PSAF (n = 39) and LSPAF (n = 51), at the mean age of 54.8 ±9.8, in mean EHRA class 2.6, underwent HABL. 64.4% of patients had a history of prior cardioversion or catheter ablation. Thirteen patients had LVEF less than 35%. Mean AF duration was 4.5 ±3.7 years. Patients were scheduled for 3-, 6- and 12-month follow-up with 7-day Holter monitoring. At 6 months after the procedure 78% (54/69) of patients were in SR. At 12 months after the procedure 86% (59/69) were in SR and 62.3% (43/69) in SR and off class I/III antiarrhythmic drugs (AADs). Only 1% (1/69) of patients required a repeat ablation for atrial flutter. A significant decrease in LA dimension and an increase in LVEF were noted. A combination of epicardial and endocardial RF ablation should be considered as a treatment option for patients with persistent and long-standing persistent atrial fibrillation as it is safe and effective in restoring sinus rhythm.

  17. Diurnal cortisol rhythm

    DEFF Research Database (Denmark)

    Harris, Anette; Endresen Reme, Silje; Tangen, Tone

    2015-01-01

    with different instruments, and cortisol in a population with LBP. Participants (n=305) sick-listed 2-10 months due to non-specific LBP were included in the study. The screening instruments were the MINI-interview, HADS and HSCL-25. Saliva cortisol were measured on 2 consecutive days; at awakening, 30min later......, at 15:00h and 22:00h. Results showed no associations between any of the main diagnostic categories from the MINI-interview, or anxiety/depression measured with HADS or HSCL-25 and cortisol. However, significant associations were found between low cortisol awakening response, low cortisol slope during...... the day and the somatization scale from HSCL-25 (dizziness or lack of energy, lack of sexual interest, the feeling that everything requires substantial efforts, difficulties to fall asleep, headache). The results indicate that cortisol, may not be directly associated with psychopathology, such as anxiety...

  18. Incidence and survival outcome according to heart rhythm during resuscitation attempt in out-of-hospital cardiac arrest patients with presumed cardiac etiology.

    Science.gov (United States)

    Rajan, Shahzleen; Folke, Fredrik; Hansen, Steen Møller; Hansen, Carolina Malta; Kragholm, Kristian; Gerds, Thomas A; Lippert, Freddy K; Karlsson, Lena; Møller, Sidsel; Køber, Lars; Gislason, Gunnar H; Torp-Pedersen, Christian; Wissenberg, Mads

    2017-05-01

    Knowledge about heart rhythm conversion from non-shockable to shockable rhythm during resuscitation attempt after out-of-hospital cardiac arrest (OHCA) and following chance of survival is limited and inconsistent. We studied 13,860 patients with presumed cardiac-caused OHCA not witnessed by the emergency medical services from the Danish Cardiac Arrest Register (2005-2012). Patients were stratified according to rhythm: shockable, converted shockable (based on receipt of subsequent defibrillation) and sustained non-shockable rhythm. Multiple logistic regression was used to identify predictors of rhythm conversion and to compute 30-day survival chances. Twenty-five percent of patients who received pre-hospital defibrillation by ambulance personnel were initially found in non-shockable rhythms. Younger age, males, witnessed arrest, shorter response time, and heart disease were significantly associated with conversion to shockable rhythm, while psychiatric- and chronic obstructive pulmonary disease were significantly associated with sustained non-shockable rhythm. Compared to sustained non-shockable rhythms, converted shockable rhythms and initial shockable rhythms were significantly associated with increased 30-day survival (Adjusted odds ratio (OR) 2.6, 95% confidence interval (CI): 1.8-3.8; and OR 16.4, 95% CI 12.7-21.2, respectively). From 2005 to 2012, 30-day survival chances increased significantly for all three groups: shockable rhythms, from 16.3% (CI: 14.2%-18.7%) to 35.7% (CI: 32.5%-38.9%); converted rhythms, from 2.1% (CI: 1.6%-2.9%) to 5.8% (CI: 4.4%-7.6%); and sustained non-shockable rhythms, from 0.6% (CI: 0.5%-0.8%) to 1.8% (CI: 1.4%-2.2%). Converting to shockable rhythm during resuscitation attempt was common and associated with nearly a three-fold higher odds of 30-day survival compared to sustained non-shockable rhythms. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Impairment of endogenous melatonin rhythm is related to the degree of chronic kidney disease (CREAM study).

    Science.gov (United States)

    Koch, Birgit C P; van der Putten, Karien; Van Someren, Eus J W; Wielders, Jos P M; Ter Wee, Piet M; Nagtegaal, J Elsbeth; Gaillard, Carlo A J M

    2010-02-01

    The nocturnal endogenous melatonin rise, which is associated with the onset of sleep propensity, is absent in haemodialysis patients. Information on melatonin rhythms in chronic kidney disease (CKD) is limited. Clear relationships exist between melatonin, core body temperature and cortisol in healthy subjects. In CKD, no data are available on these relationships. The objective of the study was to characterize the rhythms of melatonin, cortisol and temperature in relation to renal function in patients with CKD. From 28 patients (mean age 71 years) with various degrees of renal function, over a 24-h period, blood samples were collected every 2 h. An intestinal telemetric sensor was used to measure core temperature. The presence of diurnal rhythms was examined for melatonin, temperature and cortisol. Correlation analysis was performed between Cockcroft-Gault GFR (GFR), melatonin, cortisol and temperature parameters. The mean GFR was 57 +/- 30 ml/min. The subjects exhibited melatonin (n = 24) and cortisol (n = 22) rhythms. GFR was significantly correlated to melatonin amplitude (r = 0.59, P = 0.003) and total melatonin production (r = 0.51, P = 0.01), but not to temperature or cortisol rhythms. Interestingly, no associations were found between the rhythms of temperature, melatonin and cortisol. As melatonin amplitude and melatonin rhythm decreased with advancing renal dysfunction, follow-up research into circadian rhythms in patients with CKD is warranted.

  20. Circadian rhythms, sleep, and metabolism.

    Science.gov (United States)

    Huang, Wenyu; Ramsey, Kathryn Moynihan; Marcheva, Biliana; Bass, Joseph

    2011-06-01

    The discovery of the genetic basis for circadian rhythms has expanded our knowledge of the temporal organization of behavior and physiology. The observations that the circadian gene network is present in most living organisms from eubacteria to humans, that most cells and tissues express autonomous clocks, and that disruption of clock genes results in metabolic dysregulation have revealed interactions between metabolism and circadian rhythms at neural, molecular, and cellular levels. A major challenge remains in understanding the interplay between brain and peripheral clocks and in determining how these interactions promote energy homeostasis across the sleep-wake cycle. In this Review, we evaluate how investigation of molecular timing may create new opportunities to understand and develop therapies for obesity and diabetes.

  1. Temporal interactions between cortical rhythms

    Directory of Open Access Journals (Sweden)

    Anita K Roopun

    2008-12-01

    Full Text Available Multiple local neuronal circuits support different, discrete frequencies of network rhythm in neocortex. Relationships between different frequencies correspond to mechanisms designed to minimise interference, couple activity via stable phase interactions, and control the amplitude of one frequency relative to the phase of another. These mechanisms are proposed to form a framework for spectral information processing. Individual local circuits can also transform their frequency through changes in intrinsic neuronal properties and interactions with other oscillating microcircuits. Here we discuss a frequency transformation in which activity in two coactive local circuits may combine sequentially to generate a third frequency whose period is the concatenation sum of the original two. With such an interaction, the intrinsic periodicity in each component local circuit is preserved – alternate, single periods of each original rhythm form one period of a new frequency - suggesting a robust mechanism for combining information processed on multiple concurrent spatiotemporal scales.

  2. Framing the Life-Rhythm

    DEFF Research Database (Denmark)

    Munch, Anders V.

    2011-01-01

    Tracing of the notion 'rhytm' among the neo classicist architect in Denmark around 1920 that tried to vitalize the pure forms of architecture. Several of the project contributed to the artistic competions being part of the Olympic Games in that period.Both the gymnastic programme of Niels Bukh an...... and the music training of Jacques-Dalcroze based on rhythm can be seen as background, and there are elements of this vitalism developing further into modernistic architecture....

  3. Serial binary interval ratios improve rhythm reproduction

    Directory of Open Access Journals (Sweden)

    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  4. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  5. Circadian melatonin rhythm and excessive daytime sleepiness in Parkinson disease.

    Science.gov (United States)

    Videnovic, Aleksandar; Noble, Charleston; Reid, Kathryn J; Peng, Jie; Turek, Fred W; Marconi, Angelica; Rademaker, Alfred W; Simuni, Tanya; Zadikoff, Cindy; Zee, Phyllis C

    2014-04-01

    Diurnal fluctuations of motor and nonmotor symptoms and a high prevalence of sleep-wake disturbances in Parkinson disease (PD) suggest a role of the circadian system in the modulation of these symptoms. However, surprisingly little is known regarding circadian function in PD and whether circadian dysfunction is involved in the development of sleep-wake disturbances in PD. To determine the relationship between the timing and amplitude of the 24-hour melatonin rhythm, a marker of endogenous circadian rhythmicity, with self-reported sleep quality, the severity of daytime sleepiness, and disease metrics. A cross-sectional study from January 1, 2009, through December 31, 2012, of 20 patients with PD receiving stable dopaminergic therapy and 15 age-matched control participants. Both groups underwent blood sampling for the measurement of serum melatonin levels at 30-minute intervals for 24 hours under modified constant routine conditions at the Parkinson's Disease and Movement Disorders Center of Northwestern University. Twenty-four hour monitoring of serum melatonin secretion. Clinical and demographic data, self-reported measures of sleep quality (Pittsburgh Sleep Quality Index) and daytime sleepiness (Epworth Sleepiness Scale), and circadian markers of the melatonin rhythm, including the amplitude, area under the curve (AUC), and phase of the 24-hour rhythm. Patients with PD had blunted circadian rhythms of melatonin secretion compared with controls; the amplitude of the melatonin rhythm and the 24-hour AUC for circulating melatonin levels were significantly lower in PD patients (P Parkinson's Disease Rating Scale scores, levodopa equivalent dose, and global Pittsburgh Sleep Quality Index score in the PD group were not significantly related to measures of the melatonin circadian rhythm. Circadian dysfunction may underlie excessive sleepiness in PD. The nature of this association needs to be explored further in longitudinal studies. Approaches aimed to strengthen

  6. Sleep, Circadian Rhythms, and Performance During Space Shuttle Missions

    Science.gov (United States)

    Neri, David F.; Czeisler, Charles A.; Dijk, Derk-Jan; Wyatt, James K.; Ronda, Joseph M.; Hughes, Rod J.

    2003-01-01

    Sleep and circadian rhythms may be disturbed during spaceflight, and these disturbances can affect crewmembers' performance during waking hours. The mechanisms underlying sleep and circadian rhythm disturbances in space are not well understood, and effective countermeasures are not yet available. We investigated sleep, circadian rhythms, cognitive performance, and light-dark cycles in five astronauts prior to, during, and after the 16-day STS-90 mission and the IO-day STS-95 mission. The efficacy of low-dose, alternative-night, oral melatonin administration as a countermeasure for sleep disturbances was evaluated. During these missions, scheduled rest activity cycles were 20-35 minutes shorter than 24 hours. Light levels on the middeck and in the Spacelab were very low; whereas on the flight deck (which has several windows), they were highly variable. Circadian rhythm abnormalities were observed. During the second half of the missions, the rhythm of urinary cortisol appeared to be delayed relative to the sleep-wake schedule. Performance during wakefulness was impaired. Astronauts slept only about 6.5 hours per day, and subjective sleep quality was lower in space. No beneficial effects of melatonin (0.3 mg administered prior to sleep episodes on alternate nights) were observed. A surprising finding was a marked increase in rapid eye movement (REM) sleep upon return to Earth. We conclude that these Space Shuttle missions were associated with circadian rhythm disturbances, sleep loss, decrements in neurobehavioral performance, and alterations in REM sleep homeostasis. Shorter than 24-hour rest-activity schedules and exposure to light-dark cycles inadequate for optimal circadian synchronization may have contributed to these disturbances.

  7. Perspectives on the rhythm-grammar link and its implications for typical and atypical language development.

    Science.gov (United States)

    Gordon, Reyna L; Jacobs, Magdalene S; Schuele, C Melanie; McAuley, J Devin

    2015-03-01

    This paper reviews the mounting evidence for shared cognitive mechanisms and neural resources for rhythm and grammar. Evidence for a role of rhythm skills in language development and language comprehension is reviewed here in three lines of research: (1) behavioral and brain data from adults and children, showing that prosody and other aspects of timing of sentences influence online morpho-syntactic processing; (2) comorbidity of impaired rhythm with grammatical deficits in children with language impairment; and (3) our recent work showing a strong positive association between rhythm perception skills and expressive grammatical skills in young school-age children with typical development. Our preliminary follow-up study presented here revealed that musical rhythm perception predicted variance in 6-year-old children's production of complex syntax, as well as online reorganization of grammatical information (transformation); these data provide an additional perspective on the hierarchical relations potentially shared by rhythm and grammar. A theoretical framework for shared cognitive resources for the role of rhythm in perceiving and learning grammatical structure is elaborated on in light of potential implications for using rhythm-emphasized musical training to improve language skills in children. © 2015 New York Academy of Sciences.

  8. Rhythmic complexity and predictive coding: a novel approach to modeling rhythm and meter perception in music.

    Science.gov (United States)

    Vuust, Peter; Witek, Maria A G

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding (PC) as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of PC, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain's Bayesian minimization of the error between the input to the brain and the brain's prior expectations. Third, we develop a PC model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard ("rhythm") and the brain's anticipatory structuring of music ("meter"). Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the PC theory. We argue that musical rhythm exploits the brain's general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  9. Statistics for Sleep and Biological Rhythms Research.

    Science.gov (United States)

    Klerman, Elizabeth B; Wang, Wei; Phillips, Andrew J K; Bianchi, Matt T

    2017-02-01

    This article is part of a Journal of Biological Rhythms series exploring analysis and statistical topics relevant to researchers in biological rhythms and sleep research. The goal is to provide an overview of the most common issues that arise in the analysis and interpretation of data in these fields. In this article, we address issues related to the collection of multiple data points from the same organism or system at different times, since such longitudinal data collection is fundamental to the assessment of biological rhythms. Rhythmic longitudinal data require additional specific statistical considerations, ranging from curve fitting to threshold definitions to accounting for correlation structure. We discuss statistical analyses of longitudinal data including issues of correlational structure and stationarity, markers of biological rhythms, demasking of biological rhythms, and determining phase, waveform, and amplitude of biological rhythms.

  10. Integration of biological clocks and rhythms.

    Science.gov (United States)

    Refinetti, Roberto

    2012-04-01

    Animals, plants, and microorganisms exhibit numerous biological rhythms that are generated by numerous biological clocks. This article summarizes experimental data pertinent to the often-ignored issue of integration of multiple rhythms. Five contexts of integration are discussed: (i) integration of circadian rhythms of multiple processes within an individual organism, (ii) integration of biological rhythms operating in different time scales (such as tidal, daily, and seasonal), (iii) integration of rhythms across multiple species, (iv) integration of rhythms of different members of a species, and (v) integration of rhythmicity and physiological homeostasis. Understanding of these multiple rhythmic interactions is an important first step in the eventual thorough understanding of how organisms arrange their vital functions temporally within and without their bodies. © 2012 American Physiological Society. Compr Physiol 2:1213-1239, 2012.

  11. The Bidirectional Relationship between Positive Mental Health and Social Rhythm in College Students:A Three-Year Longitudinal Study

    OpenAIRE

    Dan Cai; Meixia Zhu; Muyu Lin; Xiao Chi Zhang; Jürgen Margraf

    2017-01-01

    Social rhythm refers to the general regularity of engaging in basic social activities during the week, and was found to be associated with individuals’ positive mental health. The present study investigated the relationship between social rhythm and emotional well-being in a cohort of 2,031 college students over 3 years with a cross-lagged longitudinal panel design. Results revealed that regularity of social rhythm positively predicted emotional well-being in the following year, and vice vers...

  12. Pharmacological and non-pharmacological therapy for arrhythmias in the pediatric population: EHRA and AEPC-Arrhythmia Working Group joint consensus statement.

    Science.gov (United States)

    Brugada, Josep; Blom, Nico; Sarquella-Brugada, Georgia; Blomstrom-Lundqvist, Carina; Deanfield, John; Janousek, Jan; Abrams, Dominic; Bauersfeld, Urs; Brugada, Ramon; Drago, Fabrizio; de Groot, Natasja; Happonen, Juha-Matti; Hebe, Joachim; Yen Ho, Siew; Marijon, Eloi; Paul, Thomas; Pfammatter, Jean-Pierre; Rosenthal, Eric

    2013-09-01

    In children with structurally normal hearts, the mechanisms of arrhythmias are usually the same as in the adult patient. Some arrhythmias are particularly associated with young age and very rarely seen in adult patients. Arrhythmias in structural heart disease may be associated either with the underlying abnormality or result from surgical intervention. Chronic haemodynamic stress of congenital heart disease (CHD) might create an electrophysiological and anatomic substrate highly favourable for re-entrant arrhythmias. As a general rule, prescription of antiarrhythmic drugs requires a clear diagnosis with electrocardiographic documentation of a given arrhythmia. Risk-benefit analysis of drug therapy should be considered when facing an arrhythmia in a child. Prophylactic antiarrhythmic drug therapy is given only to protect the child from recurrent supraventricular tachycardia during this time span until the disease will eventually cease spontaneously. In the last decades, radiofrequency catheter ablation is progressively used as curative therapy for tachyarrhythmias in children and patients with or without CHD. Even in young children, procedures can be performed with high success rates and low complication rates as shown by several retrospective and prospective paediatric multi-centre studies. Three-dimensional mapping and non-fluoroscopic navigation techniques and enhanced catheter technology have further improved safety and efficacy even in CHD patients with complex arrhythmias. During last decades, cardiac devices (pacemakers and implantable cardiac defibrillator) have developed rapidly. The pacing generator size has diminished and the pacing leads have become progressively thinner. These developments have made application of cardiac pacing in children easier although no dedicated paediatric pacing systems exist.

  13. Impairment of endogenous melatonin rhythm is related to the degree of chronic kidney disease (CREAM study)

    NARCIS (Netherlands)

    Koch, B.C.P.; van der Putten, K.; van Someren, E.J.W.; Wielders, J.P.M.; ter Wee, P.M.; Nagtegaal, J.E.; Gaillard, C.A.J.M.

    2010-01-01

    Background. The nocturnal endogenous melatonin rise, which is associated with the onset of sleep propensity, is absent in haemodialysis patients. Information on melatonin rhythms in chronic kidney disease (CKD) is limited. Clear relationships exist between melatonin, core body temperature and

  14. Social support and social rhythm regularity in elderly patients with major depressive disorder.

    Science.gov (United States)

    Lieverse, Ritsaert; de Vries, Rinske; Hoogendoorn, Adriaan W; Smit, Johannes H; Hoogendijk, Witte J G

    2013-11-01

    According to the social zeitgeber theory, the lack of social support (SS) may decrease circadian rhythm regularity. However, the effect of SS on social rhythms in major depression has never been investigated. The objective of this study was to investigate the relation between SS and social rhythms in elderly patients with major depression. Case-control study on the relation of SS with social rhythm regularity in 213 elderly patients with major depressive disorder (MDD) and 183 elderly healthy comparison subjects (HCs). Social rhythm regularity was studied using the social rhythm metric (SRM-5), in which a lower score represents less regularity. SS was assessed with the social support list (SSL). Patients with MDD displayed lower SRM-5 scores than HCs (4.94 ± 0.94 versus 5.38 ± 1.12; p = 0.003), as well as lower SSL-interactions (60.0 ± 13.7 versus 70.5 ± 11.6; p 0.05). Patients with MDD showed lower social rhythm regularity as well as lower measures of SS than HCs. In HCs, high SS was correlated with low social rhythm regularity, suggesting that increases in SS in combination with a healthy organization of circadian rhythms allow the social rhythms to become less rigid. Interestingly, in MDD, no correlation was found, suggesting that patients have a blunted response to social stimuli and may, therefore, benefit from treatment that increases the susceptibility to SS. Copyright © 2013 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  15. The role of rhythm in perceiving speech in noise: a comparison of percussionists, vocalists and non-musicians.

    Science.gov (United States)

    Slater, Jessica; Kraus, Nina

    2016-02-01

    The natural rhythms of speech help a listener follow what is being said, especially in noisy conditions. There is increasing evidence for links between rhythm abilities and language skills; however, the role of rhythm-related expertise in perceiving speech in noise is unknown. The present study assesses musical competence (rhythmic and melodic discrimination), speech-in-noise perception and auditory working memory in young adult percussionists, vocalists and non-musicians. Outcomes reveal that better ability to discriminate rhythms is associated with better sentence-in-noise (but not words-in-noise) perception across all participants. These outcomes suggest that sensitivity to rhythm helps a listener understand unfolding speech patterns in degraded listening conditions, and that observations of a "musician advantage" for speech-in-noise perception may be mediated in part by superior rhythm skills.

  16. Circadian Rest-Activity Rhythm in Pediatric Type 1 Narcolepsy.

    Science.gov (United States)

    Filardi, Marco; Pizza, Fabio; Bruni, Oliviero; Natale, Vincenzo; Plazzi, Giuseppe

    2016-06-01

    Pediatric type 1 narcolepsy is often challenging to diagnose and remains largely undiagnosed. Excessive daytime sleepiness, disrupted nocturnal sleep, and a peculiar phenotype of cataplexy are the prominent features. The knowledge available about the regulation of circadian rhythms in affected children is scarce. This study compared circadian rest-activity rhythm and actigraphic estimated sleep measures of children with type 1 narcolepsy versus healthy controls. Twenty-two drug-naïve type 1 narcolepsy children and 21 age- and sex- matched controls were monitored for seven days during the school week by actigraphy. Circadian activity rhythms were analyzed through functional linear modeling; nocturnal and diurnal sleep measures were estimated from activity using a validated algorithm. Children with type 1 narcolepsy presented an altered rest-activity rhythm characterized by enhanced motor activity throughout the night and blunted activity in the first afternoon. No difference was found between children with type 1 narcolepsy and controls in the timing of the circadian phase. Actigraphic sleep measures showed good discriminant capabilities in assessing type 1 narcolepsy nycthemeral disruption. Actigraphy reliably renders the nycthemeral disruption typical of narcolepsy type 1 in drug-naïve children with recent disease onset, indicating the sensibility of actigraphic assessment in the diagnostic work-up of childhood narcolepsy type 1. © 2016 Associated Professional Sleep Societies, LLC.

  17. Lithium and bipolar disorder: Impacts from molecular to behavioural circadian rhythms.

    Science.gov (United States)

    Moreira, Jeverson; Geoffroy, Pierre Alexis

    2016-01-01

    Bipolar disorder (BD) is a severe and common psychiatric disorder. BD pathogenesis, clinical manifestations and relapses are associated with numerous circadian rhythm abnormalities. Lithium (Li) is the first-line treatment in BD, and its therapeutic action has been related to its ability to alter circadian rhythms. We systematically searched the PubMed database until January 2016, aiming to critically examine published studies investigating direct and indirect effects of Li on circadian rhythms. The results, from the 95 retained studies, indicated that Li: acts directly on the molecular clocks; delays the phase of sleep-wakefulness rhythms and the peak elevation of diurnal cycle body temperature; reduces the amplitude and shortens the duration of activity rhythms and lengthens free-running rhythms. Chronic Li treatment stabilizes free-running activity rhythms, by improving day-to-day rhythmicity of the activity, with effects that appear to be dose related. Pharmacogenetics demonstrate several associations of Li's response with circadian genes (NR1D1, GSK3β, CRY1, ARNTL, TIM, PER2). Finally, Li acts on the retinal-hypothalamic pineal pathway, influencing light sensitivity and melatonin secretion. Li is a highly investigated chronobiologic agent, and although its chronobiological effects are not completely understood, it seems highly likely that they constitute an inherent component of its therapeutic action in the treatment of mood disorders.

  18. Music and speech prosody: a common rhythm.

    Science.gov (United States)

    Hausen, Maija; Torppa, Ritva; Salmela, Viljami R; Vainio, Martti; Särkämö, Teppo

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61) using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA) and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception, and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks) was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress).

  19. Music and speech prosody: A common rhythm

    Directory of Open Access Journals (Sweden)

    Maija eHausen

    2013-09-01

    Full Text Available Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61 using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress.

  20. Music and speech prosody: a common rhythm

    Science.gov (United States)

    Hausen, Maija; Torppa, Ritva; Salmela, Viljami R.; Vainio, Martti; Särkämö, Teppo

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61) using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA) and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception, and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks) was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress). PMID:24032022

  1. Sleep and circadian rhythms in space.

    Science.gov (United States)

    Stampi, C

    1994-05-01

    This paper presents a detailed critical review of the knowledge accumulated in the last three decades concerning research on sleep, work-rest schedules, and circadian rhythms in space. The focus of the paper is preceded by a brief review of the basic principles of the human circadian system and the physiology of the sleep-wake cycle, relevant to understanding the problem of astronaut work-rest scheduling. Much of what is known is based on anecdotal reports, mission log books, and debriefing of astronauts after flights. The broad literature reviewed, which includes studies from American and Soviet space missions, as well as some studies conducted under simulated weightlessness, offers just a handful of objective studies on the physiology of sleep and circadian rhythms in space. Nevertheless, the data are remarkably consistent, and indicate that sleep can be of reasonably good quality in space. The risk of sleep loss and associated performance degradation appears to be a manageable one. However, one clear conclusion arises from this review: whatever the type of mission of flight plan, its success will depend on whether the principles of circadian and sleep-wake regulation have been taken into account during the planning phase of work-rest schedules. That is, satisfactory sleep and alertness is more likely to occur if crews maintain a reasonable (i.e., constant) relation with their normal terrestrial rhythm. This is not as easy a task as it may appear; indeed, unexpected, high-intensity operational demands have been the major cause of acute problems of sleep loss and performance degradation in space. Moreover, the growing complexity of space missions indicate that emergencies will never disappear. Therefore, one of the most important research challenges for future space missions is the development of strategies that could permit astronauts to function closest to maximal efficiency during intensive and prolonged work. Countermeasures for optimizing astronaut

  2. Introduction to Focus Issue: Rhythms and Dynamic Transitions in Neurological Disease: Modeling, Computation, and Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, Tasso J., E-mail: tasso@bu.edu; Kramer, Mark A., E-mail: mak@bu.edu [Department of Mathematics and Statistics, Boston University, Boston, Massachusetts 02215 (United States); Rotstein, Horacio G., E-mail: horacio@njit.edu [Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States)

    2013-12-15

    Rhythmic neuronal oscillations across a broad range of frequencies, as well as spatiotemporal phenomena, such as waves and bumps, have been observed in various areas of the brain and proposed as critical to brain function. While there is a long and distinguished history of studying rhythms in nerve cells and neuronal networks in healthy organisms, the association and analysis of rhythms to diseases are more recent developments. Indeed, it is now thought that certain aspects of diseases of the nervous system, such as epilepsy, schizophrenia, Parkinson's, and sleep disorders, are associated with transitions or disruptions of neurological rhythms. This focus issue brings together articles presenting modeling, computational, analytical, and experimental perspectives about rhythms and dynamic transitions between them that are associated to various diseases.

  3. Development of cortisol circadian rhythm in infancy.

    NARCIS (Netherlands)

    Weerth, C. de; Zijl, R.H.

    2003-01-01

    BACKGROUND AND AIMS: Cortisol is the final product of the hypothalamus-pituitary-adrenal (HPA) axis. It is secreted in a pulsatile fashion that displays a circadian rhythm. Infants are born without a circadian rhythm in cortisol and they acquire it during their first year of life. Studies do not

  4. The Essential Connection between Rhythm and Movement

    Science.gov (United States)

    Perlmutter, Adam

    2009-01-01

    It is the most fundamental aspect of music, yet so many students struggle with rhythm. How does one effectively teach budding young musicians to properly feel and read the rhythms all around them? Eileen Benedict, vocal music specialist at the Edith L. Slocum School in Ronkonkoma, New York, finds it best to start teaching her young students not…

  5. The Incarnate Rhythm of Geometrical Knowing

    Science.gov (United States)

    Bautista, Alfredo; Roth, Wolff-Michael

    2012-01-01

    Rhythm is a fundamental dimension of human nature at both biological and social levels. However, existing research literature has not sufficiently investigated its role in mathematical cognition and behavior. The purpose of this article is to bring the concept of "incarnate rhythm" into current discourses in the field of mathematical learning and…

  6. Quantifying Speech Rhythm Abnormalities in the Dysarthrias

    Science.gov (United States)

    Liss, Julie M.; White, Laurence; Mattys, Sven L.; Lansford, Kaitlin; Lotto, Andrew J.; Spitzer, Stephanie M.; Caviness, John N.

    2009-01-01

    Purpose: In this study, the authors examined whether rhythm metrics capable of distinguishing languages with high and low temporal stress contrast also can distinguish among control and dysarthric speakers of American English with perceptually distinct rhythm patterns. Methods: Acoustic measures of vocalic and consonantal segment durations were…

  7. Accelerated idioventricular rhythm during flexible fiberoptic bronchoscopy

    Energy Technology Data Exchange (ETDEWEB)

    Borgeat, A.; Chiolero, R.; Mosimann, B.; Freeman, J.

    1987-03-01

    We report the case of a patient who developed severe hypoxemia and an unusual arrhythmia, accelerated idioventricular rhythm, during flexible fiberoptic bronchoscopy. Coronary artery disease was subsequently suspected despite an unremarkable history and physical examination, and confirmed by a thallium 201 imaging. The appearance of accelerated idioventricular rhythm during fiberoptic bronchoscopy should raise the possibility of underlying coronary artery disease.

  8. Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. E.; Gohel, Bakul; Kim, K.; Kwon, H.; An, Kyung Min [Center for Biosignals, Korea Research Institute of Standards and Science(KRISS), Daejeon (Korea, Republic of)

    2015-12-15

    Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8–13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

  9. Circadian rhythms and circadian rhythm disorders in children and adolescents.

    Science.gov (United States)

    Garcia, J; Rosen, G; Mahowald, M

    2001-12-01

    A clinically applicable review of circadian rhythm physiology is presented, including a detailed examination of the interaction of circadian and homeostatic systems and the maturation of the circadian system from preconception through adolescence. Emphasis is placed on the clinical evaluation gathering information through the history, sleep log, and if necessary, actigraphy and polysomnography. Circadian disorders, including advanced sleep phase syndrome, circadian disorders seen in blind children, delayed sleep phase syndrome, and non-24-hour sleep phase are described. Case descriptions of each are provided. Treatment and interventions for these disorders are described, including the importance of education, light therapy, sleep-wake schedule adjustments, and the occasional use of medications, such as sedative hypnotics and melatonin.

  10. [Biology and genetics of circadian rhythm].

    Science.gov (United States)

    Bellivier, F

    2009-01-01

    In recent decades our knowledge of the molecular mechanisms of biological clocks has grown expontentially. This has helped to guide the choice of genes studied to explain inter-individual variations seen in circadian rhythms. In recent years analysis of circadian rhythms has advanced considerably into the study of pathological circadian rhythms in human beings. These findings, combined with those obtained from studying mice whose circadian genes have been rendered incapable, have revealed the role of genetic factors in circadian rhythms. This literature review presents an overview of these findings. Beyond our understanding of the functioning of these biological clocks, this knowledge will be extremely useful to analyse genetic factors involved in morbid conditions involving circadian rhythm abnormalities.

  11. Clinical learning environments: place, artefacts and rhythm.

    Science.gov (United States)

    Sheehan, Dale; Jowsey, Tanisha; Parwaiz, Mariam; Birch, Mark; Seaton, Philippa; Shaw, Susan; Duggan, Alison; Wilkinson, Tim

    2017-10-01

    Health care practitioners learn through experience in clinical environments in which supervision is a key component, but how that learning occurs outside the supervision relationship remains largely unknown. This study explores the environmental factors that inform and support workplace learning within a clinical environment. An observational study drawing on ethnographic methods was undertaken in a general medicine ward. Observers paid attention to interactions among staff members that involved potential teaching and learning moments that occurred and were visible in the course of routine work. General purpose thematic analysis of field notes was undertaken. A total of 376 observations were undertaken and documented. The findings suggest that place (location of interaction), rhythm (regularity of activities occurring in the ward) and artefacts (objects and equipment) were strong influences on the interactions and exchanges that occurred. Each of these themes had inherent tensions that could promote or inhibit engagement and therefore learning opportunities. Although many learning opportunities were available, not all were taken up or recognised by the participants. We describe and make explicit how the natural environment of a medical ward and flow of work through patient care contribute to the learning architecture, and how this creates or inhibits opportunities for learning. Awareness of learning opportunities was often tacit and not explicit for either supervisor or learner. We identify strategies through which tensions inherent within space, artefacts and the rhythms of work can be resolved and learning opportunities maximised. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  12. Ambulatory but sedentary : Impact on cognition and the rest-activity rhythm in nursing home residents with dementia

    NARCIS (Netherlands)

    Eggermont, Laura H. P.; Scherder, Erik J. A.

    Physical activity has been positively associated with cognition and the rest-activity rhythm. In the present study, nursing staff classified ambulatory nursing home residents with moderate dementia either as active (n = 42) or as sedentary (n = 34). We assessed the rest-activity rhythm by means of

  13. Biological rhythms in bipolar and depressive disorders: A community study with drug-naïve young adults.

    Science.gov (United States)

    Duarte Faria, Augusto; Cardoso, Taiane de Azevedo; Campos Mondin, Thaise; Souza, Luciano Dias de Mattos; Magalhaes, Pedro Vieira da Silva; Patrick Zeni, Cristian; Silva, Ricardo Azevedo da; Kapczinski, Flavio; Jansen, Karen

    2015-11-01

    To assess biological rhythm disruptions among drug-naïve young adults with bipolar disorder (BD), major depressive disorder (MDD), and community controls. This was a cross-sectional study nested in a population-based study. BD and MDD were diagnosed using the Structured Clinical Interview for DSM-IV. Biological rhythm disruptions were assessed using the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN). Two hundred seventeen subjects were assessed (49 BD, 74 MDD, and 94 community controls). Biological rhythm disruption was higher in subjects with BD (40.32±9.92; pbiological rhythms. Bipolar disorder and major depressive disorder are associated with disruption in biological rhythm. In addition, disruption in sleep/social rhythms is higher in subjects with BD when compared to subjects with MDD. We also verified biological rhythm disruption in subjects with BD during euthymic status, but not in remitted MDD. Regulation of biological rhythm may be a means to identify patients with mood disorders and potentially differentiate MDD from BD. Copyright © 2015. Published by Elsevier B.V.

  14. Long-term effects of cognitive therapy on biological rhythms and depressive symptoms: A randomized clinical trial.

    Science.gov (United States)

    Mondin, Thaíse Campos; Cardoso, Taiane de Azevedo; Jansen, Karen; Silva, Giovanna Del Grande da; Souza, Luciano Dias de Mattos; Silva, Ricardo Azevedo da

    2015-11-15

    To evaluate the effect of cognitive therapy on biological rhythm and depressive and anxious symptoms in a twelve-month follow-up period. In addition, correlations between the reduction of depression and anxiety symptoms and the regulation of biological rhythm were observed. This was a randomized clinical trial with young adults from 18 to 29 years of age who were diagnosed with depression. Two models of psychotherapy were used: Cognitive Behavioral Therapy (CBT) and Narrative Cognitive Therapy (NCT). Biological rhythm was assessed with the Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN). Severity of depressive and anxious symptoms was assessed by the Hamilton Depression Rating Scale (HDRS) and the Hamilton Anxiety Rating Scale (HARS), respectively. The sample included 97 patients who were divided within the protocols of psychotherapy. There was a significant reduction in depressive and anxious symptoms (pbiological rhythm (pbiological rhythm (r=0.638; pbiological rhythm (r=0.438; pbiological rhythm at a twelve-month follow-up evaluation. This study highlights the association between biological rhythm and symptoms of depression and anxiety. We did not assess genetic, hormonal or neurochemical factors and we did not include patients under pharmaceutical treatment or those with severe symptomatology. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Circadian rhythms in a nutshell.

    Science.gov (United States)

    Edery, I

    2000-08-09

    Living organisms on this planet have adapted to the daily rotation of the earth on its axis. By means of endogenous circadian clocks that can be synchronized to the daily and seasonal changes in external time cues, most notably light and temperature, life forms anticipate environmental transitions, perform activities at biologically advantageous times during the day, and undergo characteristic seasonal responses. The effects of transmeridian flight and shift work are stark reminders that although modern technologies can create "cities that never sleep" we cannot escape the recalcitrance of endogenous clocks that regulate much of our physiology and behavior. Moreover, malfunctions in the human circadian timing system are implicated in several disorders, including chronic sleep disorders in the elderly, manic-depression, and seasonal affective disorders (SAD or winter depression). Recent progress in understanding the molecular mechanisms underlying circadian rhythms has been remarkable. In its most basic form, circadian clocks are comprised of a set of proteins that, by virtue of the design principles involved, generate a self-sustaining transcriptional-translational feedback loop with a free-running period of about 24 h. One or more of the clock components is acutely sensitive to light, resulting in an oscillator that can be synchronized to local time. This review provides an overview of the roles circadian clocks play in nature, how they might have arisen, human health concerns related to clock dysfunction, and mainly focuses on the clockworks found in Drosophila and mice, the two best studied animal model systems for understanding the biochemical and cellular bases of circadian rhythms.

  16. Protecting the melatonin rhythm through circadian healthy light exposure.

    OpenAIRE

    Maria Angeles Bonmati-Carrion; Raquel Arguelles-Prieto; Maria Jose Martinez-Madrid; Russel Reiter; Ruediger Hardeland; Maria Angeles Rol; Juan Antonio Madrid

    2014-01-01

    Currently, in developed countries, nights are excessively illuminated (light at night), whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD), including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated ...

  17. Sleep, circadian rhythm and body weight: parallel developments.

    Science.gov (United States)

    Westerterp-Plantenga, Margriet S

    2016-11-01

    Circadian alignment is crucial for body-weight management, and for metabolic health. In this context, circadian alignment consists of alignment of sleep, meal patterns and physical activity. During puberty a significant reduction in sleep duration occurs, and pubertal status is inversely associated with sleep duration. A consistent inverse association between habitual sleep duration and body-weight development occurs, independent of possible confounders. Research on misalignment reveals that circadian misalignment affects sleep-architecture and subsequently disturbs glucose-insulin metabolism, substrate oxidation, leptin- and ghrelin concentrations, appetite, food reward, hypothalamic-pituitary-adrenal-axis activity and gut-peptide concentrations enhancing positive energy balance and metabolic disturbance. Not only aligning meals and sleep in a circadian way is crucial, also regular physical activity during the day strongly promotes the stability and amplitude of circadian rhythm, and thus may serve as an instrument to restore poor circadian rhythms. Endogenicity may play a role in interaction of these environmental variables with a genetic predisposition. In conclusion, notwithstanding the separate favourable effects of sufficient daily physical activity, regular meal patterns, sufficient sleep duration and quality sleep on energy balance, the overall effect of the amplitude and stability of the circadian rhythm, perhaps including genetic predisposition, may integrate the separate effects in an additive way.

  18. Spontaneous internal desynchronization of locomotor activity and body temperature rhythms from plasma melatonin rhythm in rats exposed to constant dim light

    Directory of Open Access Journals (Sweden)

    Bullock Nicole M

    2006-04-01

    Full Text Available Abstract Background We have recently reported that spontaneous internal desynchronization between the locomotor activity rhythm and the melatonin rhythm may occur in rats (30% of tested animals when they are maintained in constant dim red light (LLdim for 60 days. Previous work has also shown that melatonin plays an important role in the modulation of the circadian rhythms of running wheel activity (Rw and body temperature (Tb. The aim of the present study was to investigate the effect that desynchronization of the melatonin rhythm may have on the coupling and expression of circadian rhythms in Rw and Tb. Methods Rats were maintained in a temperature controlled (23–24°C ventilated lightproof room under LLdim (red dim light 1 μW/cm2 [5 Lux], lower wavelength cutoff at 640 nm. Animals were individually housed in cages equipped with a running wheel and a magnetic sensor system to detect wheel rotation; Tb was monitored by telemetry. Tb and Rw data were recorded in 5-min bins and saved on disk. For each animal, we determined the mesor and the amplitude of the Rw and Tb rhythm using waveform analysis on 7-day segments of the data. After sixty days of LLdim exposure, blood samples (80–100 μM were collected every 4 hours over a 24-hrs period from the tail artery, and serum melatonin levels were measured by radioimmunoassay. Results Twenty-one animals showed clear circadian rhythms Rw and Tb, whereas one animal was arrhythmic. Rw and Tb rhythms were always strictly associated and we did not observe desynchronization between these two rhythms. Plasma melatonin levels showed marked variations among individuals in the peak levels and in the night-to-day ratio. In six rats, the night-to-day ratio was less than 2, whereas in the rat that showed arrhythmicity in Rw and Tb melatonin levels were high and rhythmic with a large night-to-day ratio. In seven animals, serum melatonin levels peaked during the subjective day (from CT0 to CT8, thus suggesting

  19. Molecular control of circadian metabolic rhythms

    National Research Council Canada - National Science Library

    Siming Li; Jiandie D. Lin

    2009-01-01

    Circadian metabolic rhythms are fundamental to the control of nutrient and energy homeostasis, as well as the pathogenesis of metabolic disease, such as obesity, lipid disorders, and type 2 diabetes...

  20. Daily rhythms in mobile telephone communication

    CERN Document Server

    Aledavood, Talayeh; Roberts, Sam G B; Reed-Tsochas, Felix; Moro, Esteban; Dunbar, Robin I M; Saramäki, Jari

    2015-01-01

    Circadian rhythms are known to be important drivers of human activity and the recent availability of electronic records of human behaviour has provided fine-grained data of temporal patterns of activity on a large scale. Further, questionnaire studies have identified important individual differences in circadian rhythms, with people broadly categorised into morning-like or evening-like individuals. However, little is known about the social aspects of these circadian rhythms, or how they vary across individuals. In this study we use a unique 18-month dataset that combines mobile phone calls and questionnaire data to examine individual differences in the daily rhythms of mobile phone activity. We demonstrate clear individual differences in daily patterns of phone calls, and show that these individual differences are persistent despite a high degree of turnover in the individuals' social networks. Further, women's calls were longer than men's calls, especially during the evening and at night, and these calls wer...

  1. Strength of gamma rhythm depends on normalization

    National Research Council Canada - National Science Library

    Ray, Supratim; Ni, Amy M; Maunsell, John H R

    2013-01-01

    ...), whose magnitude depends on the attentional load. This has led to the suggestion that gamma rhythms form dynamic communication channels across cortical areas processing the features of behaviorally relevant stimuli...

  2. Clock Genes and Altered Sleep–Wake Rhythms: Their Role in the Development of Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Annaëlle Charrier

    2017-04-01

    Full Text Available In mammals, the circadian clocks network (central and peripheral oscillators controls circadian rhythms and orchestrates the expression of a range of downstream genes, allowing the organism to anticipate and adapt to environmental changes. Beyond their role in circadian rhythms, several studies have highlighted that circadian clock genes may have a more widespread physiological effect on cognition, mood, and reward-related behaviors. Furthermore, single nucleotide polymorphisms in core circadian clock genes have been associated with psychiatric disorders (such as autism spectrum disorder, schizophrenia, anxiety disorders, major depressive disorder, bipolar disorder, and attention deficit hyperactivity disorder. However, the underlying mechanisms of these associations remain to be ascertained and the cause–effect relationships are not clearly established. The objective of this article is to clarify the role of clock genes and altered sleep–wake rhythms in the development of psychiatric disorders (sleep problems are often observed at early onset of psychiatric disorders. First, the molecular mechanisms of circadian rhythms are described. Then, the relationships between disrupted circadian rhythms, including sleep–wake rhythms, and psychiatric disorders are discussed. Further research may open interesting perspectives with promising avenues for early detection and therapeutic intervention in psychiatric disorders.

  3. Circadian rhythms, athletic performance, and jet lag

    OpenAIRE

    Manfredini, R; Manfredini, F.; Fersini, C.; Conconi, F.

    1998-01-01

    Rapid air travel across several time zones exposes the traveller to a shift in his/her internal biological clock. The result is a transient desynchronisation of the circadian rhythm, called jet lag, lasting until the rhythm is rephased to the new environmental conditions. The most commonly experienced symptoms are sleep disorders, difficulties with concentrating, irritability, depression, fatigue, disorientation, loss of appetite, and gastrointestinal disturbance. Apart from the decreme...

  4. "Ritual Rhythms" - a collaborative WebDocumentary

    DEFF Research Database (Denmark)

    Møhl, Perle

    2014-01-01

    A collaborative web-based filmproject in 11 vignettes about the rituals and rhythms of daily life in various locations & settings in the city of Copenhagen. Created by Perle Møhl and the students on the 2014 courses in Visual Anthropology in Practice. We use the concepts of Ritual and Rhythm......, tuning in with all our senses to the details of daily life that often elude the attention of a wordy anthropology....

  5. Clinical predictors of shockable versus non-shockable rhythms in patients with out-of-hospital cardiac arrest.

    Science.gov (United States)

    Granfeldt, Asger; Wissenberg, Mads; Hansen, Steen Møller; Lippert, Freddy K; Lang-Jensen, Torsten; Hendriksen, Ole Mazur; Torp-Pedersen, Christian; Christensen, Erika Frischknecht; Christiansen, Christian Fynbo

    2016-11-01

    To identify factors associated with a non-shockable rhythm as first recorded heart rhythm. Patients ≥18 years old suffering out-of-hospital cardiac arrest between 2001 and 2012 were identified in the population-based Danish Cardiac Arrest Registry. Danish administrative registries were used to identify chronic diseases (within 10 years) and drug prescriptions (within 180 days). A multivariable logistic regression model, including patient related and cardiac arrest related characteristics, was used to estimate odds ratios (OR) for factors associated with non-shockable rhythm. A total of 29,863 patients were included: 6600 (22.1%) patients with a shockable rhythm and 23,263 (77.9%) patients with a non-shockable rhythm. A non-shockable rhythm was associated with female gender, arrest in private home, unwitnessed arrest, no bystander CPR, and longer time to first rhythm analysis compared to patients with shockable rhythm. In the adjusted multivariable regression model, pre-existing non-cardiovascular disease and drug prescription were associated with a non-shockable rhythm e.g. chronic obstructive lung disease (OR 1.44 [95% CI: 1.32-1.58]); and the prescription for antidepressants (OR 1.49 [95% CI: 1.35-1.65]), antipsychotics (OR 2.30 [95% CI: 1.96-2.69]) analgesics (OR 1.32 [95% CI: 1.23-1.41]), corticosteroids (OR 1.64 [95% CI: 1.44-1.85]), and antibiotics (OR 1.59 [95% CI: 1.40-1.81]). In contrast, the prescription of cardiovascular drugs and a history of cardiovascular disease e.g. ischemic heart disease was associated with a lower risk of non-shockable rhythm (OR 0.66 [95% CI: 0.60-0.71]). This study demonstrate that non-cardiovascular disease and medication prescription are associated with a non-shockable rhythm while cardiovascular disease and medication prescription are associated with a shockable rhythm as first recorded rhythm in patients with OHCA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Biological rhythms during residence in polar regions.

    Science.gov (United States)

    Arendt, Josephine

    2012-05-01

    At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin and/or its metabolite 6-sulfatoxymelatonin (aMT6s) provide probably the best index of circadian (and seasonal) timing. A frequent observation has been a delay of the circadian system in winter. A skeleton photoperiod (2 × 1-h, bright white light, morning and evening) can restore summer timing. A single 1-h pulse of light in the morning may be sufficient. A few people desynchronize from the 24-h day (free-run) and show their intrinsic circadian period, usually >24 h. With regard to general health in polar regions, intermittent reports describe abnormalities in various physiological processes from the point of view of daily and seasonal rhythms, but positive health outcomes are also published. True winter depression (SAD) appears to be rare, although subsyndromal SAD is reported. Probably of most concern are the numerous reports of sleep problems. These have prompted investigations of the underlying mechanisms and treatment interventions. A delay of the circadian system with "normal" working hours implies sleep is attempted at a suboptimal phase. Decrements in sleep efficiency, latency, duration, and quality are also seen in winter. Increasing the intensity of ambient light exposure throughout the day advanced circadian phase and was associated with benefits for sleep: blue-enriched light was slightly more effective than standard white light. Effects on performance remain to be fully investigated. At 75°S, base personnel adapt the circadian system to night work within a week

  7. Rhythms of ghrelin, leptin, and sleep in rats: effects of the normal diurnal cycle, restricted feeding, and sleep deprivation.

    Science.gov (United States)

    Bodosi, B; Gardi, J; Hajdu, I; Szentirmai, E; Obal, F; Krueger, J M

    2004-11-01

    To determine the relationships among plasma ghrelin and leptin concentrations and hypothalamic ghrelin contents, and sleep, cortical brain temperature (Tcrt), and feeding, we determined these parameters in rats in three experimental conditions: in free-feeding rats with normal diurnal rhythms, in rats with feeding restricted to the 12-h light period (RF), and in rats subjected to 5-h of sleep deprivation (SD) at the beginning of the light cycle. Plasma ghrelin and leptin displayed diurnal rhythms with the ghrelin peak preceding and the leptin peak following the major daily feeding peak in hour 1 after dark onset. RF reversed the diurnal rhythm of these hormones and the rhythm of rapid-eye-movement sleep (REMS) and significantly altered the rhythm of Tcrt. In contrast, the duration and intensity of non-REMS (NREMS) were hardly responsive to RF. SD failed to change leptin concentrations, but it promptly stimulated plasma ghrelin and induced eating. SD elicited biphasic variations in the hypothalamic ghrelin contents. SD increased plasma corticosterone, but corticosterone did not seem to influence either leptin or ghrelin. The results suggest a strong relationship between feeding and the diurnal rhythm of leptin and that feeding also fundamentally modulates the diurnal rhythm of ghrelin. The variations in hypothalamic ghrelin contents might be associated with sleep-wake activity in rats, but, unlike the previous observations in humans, obvious links could not be detected between sleep and the diurnal rhythms of plasma concentrations of either ghrelin or leptin in the rat. Copyright 2004 American Physiological Society

  8. Amyloid Beta Peptides Differentially Affect Hippocampal Theta Rhythms In Vitro

    Directory of Open Access Journals (Sweden)

    Armando I. Gutiérrez-Lerma

    2013-01-01

    Full Text Available Soluble amyloid beta peptide (Aβ is responsible for the early cognitive dysfunction observed in Alzheimer's disease. Both cholinergically and glutamatergically induced hippocampal theta rhythms are related to learning and memory, spatial navigation, and spatial memory. However, these two types of theta rhythms are not identical; they are associated with different behaviors and can be differentially modulated by diverse experimental conditions. Therefore, in this study, we aimed to investigate whether or not application of soluble Aβ alters the two types of theta frequency oscillatory network activity generated in rat hippocampal slices by application of the cholinergic and glutamatergic agonists carbachol or DHPG, respectively. Due to previous evidence that oscillatory activity can be differentially affected by different Aβ peptides, we also compared Aβ25−35 and Aβ1−42 for their effects on theta rhythms in vitro at similar concentrations (0.5 to 1.0 μM. We found that Aβ25−35 reduces, with less potency than Aβ1−42, carbachol-induced population theta oscillatory activity. In contrast, DHPG-induced oscillatory activity was not affected by a high concentration of Aβ25−35 but was reduced by Aβ1−42. Our results support the idea that different amyloid peptides might alter specific cellular mechanisms related to the generation of specific neuronal network activities, instead of exerting a generalized inhibitory effect on neuronal network function.

  9. Sparse gamma rhythms arising through clustering in adapting neuronal networks.

    Directory of Open Access Journals (Sweden)

    Zachary P Kilpatrick

    2011-11-01

    Full Text Available Gamma rhythms (30-100 Hz are an extensively studied synchronous brain state responsible for a number of sensory, memory, and motor processes. Experimental evidence suggests that fast-spiking interneurons are responsible for carrying the high frequency components of the rhythm, while regular-spiking pyramidal neurons fire sparsely. We propose that a combination of spike frequency adaptation and global inhibition may be responsible for this behavior. Excitatory neurons form several clusters that fire every few cycles of the fast oscillation. This is first shown in a detailed biophysical network model and then analyzed thoroughly in an idealized model. We exploit the fact that the timescale of adaptation is much slower than that of the other variables. Singular perturbation theory is used to derive an approximate periodic solution for a single spiking unit. This is then used to predict the relationship between the number of clusters arising spontaneously in the network as it relates to the adaptation time constant. We compare this to a complementary analysis that employs a weak coupling assumption to predict the first Fourier mode to destabilize from the incoherent state of an associated phase model as the external noise is reduced. Both approaches predict the same scaling of cluster number with respect to the adaptation time constant, which is corroborated in numerical simulations of the full system. Thus, we develop several testable predictions regarding the formation and characteristics of gamma rhythms with sparsely firing excitatory neurons.

  10. Circadian activity rhythms for mothers with an infant in ICU

    Directory of Open Access Journals (Sweden)

    Shih-Yu eLee

    2010-12-01

    Full Text Available Circadian rhythms influence sleep and wakefulness. Circadian activity rhythms (CAR are altered in individuals with dementia or seasonal affective disorder. To date, studies exploring CAR and sleep in postpartum women are rare. The purpose of this report is to describe relationships between CAR, sleep disturbance, and fatigue among 72 first-time mothers during their 2nd week postpartum while their newborn remain hospitalized in intensive care unit (ICU. Seventy two mothers were included in this secondary data analysis sample from three separate studies. Participants completed the General Sleep Disturbance Scale (GSDS, Numerical Rating Scale for Fatigue (NRS-F, and a sleep diary. The objective sleep data included total sleep time (TST, wake after sleep onset (WASO, and CAR determined by the circadian quotient (amplitude/mesor averaged from at least 48-hours of wrist actigraphy monitoring. The TST of mothers who self-reported as poor sleepers was 354 minutes (SEM= 21.9, with a mean WASO of 19.5% (SEM= 2.8. The overall sleep quality measured by the GSDS was clinically, significantly disrupted (M= 5.5, SD= 1.2. The mean score for morning fatigue was 5.8 (SD= 2.0, indicating moderate fatigue severity. The CAR was .62 (SEM= .04, indicating poor synchronization. The self-reported good sleepers (GSDS < 3 had better CAR (M= .71, SEM= .02 than poor sleepers (GSDS > 3 (t [70] = 2.0, p< .05. A higher circadian equation was associated with higher TST (r= .83, p<.001, less WASO (r= -.50, p< .001, lower self-reported sleep disturbance scores (r= -.35, p= .01, and less morning fatigue (r= -.26. Findings indicate that mothers with a hospitalized infant have both nocturnal sleep problems and disturbed circadian activity rhythms. Factors responsible for these sleep and rhythm disturbances, the adverse effects on mother’s physical and mental well-being, and mother-infant relationship require further study.

  11. Biological rhythms, metabolic syndrome and current depressive episode in a community sample.

    Science.gov (United States)

    Moreira, Fernanda Pedrotti; Jansen, Karen; Mondin, Thaíse Campos; Cardoso, Taiane de Azevedo; Magalhães, Pedro Vieira da Silva; Kapczinski, Flavio; Frey, Benicio N; Oses, Jean Pierre; Souza, Luciano Dias de Mattos; da Silva, Ricardo Azevedo; Wiener, Carolina David

    2016-10-01

    The purpose of this study was to assess the disruption in biological rhythms and metabolic syndrome (MetS) in individuals with depressive episode. This was a cross-sectional, population-based study with a representative sample of 905 young adults. Current depressive episode were confirmed by a psychologist using the Mini International Neuropsychiatric Interview (MINI)-Plus. Self-reported biological rhythms were assessed using the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN). MetS was defined using modified NCEP/ATPIII criteria. Significant main effects of current depressive episode (pbiological rhythm scores (p=0.002, η(2)=0.011) as well as sleep (p=0.001, η(2)=0.016) and social domains (pbiological rhythms are associated with key components of the MetS in community adults with MDD. The understanding of the complex interactions between biological rhythms, MetS and depression are important in the development of preventive and therapeutic strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Circadian Rhythm of Glomerular Filtration and Solute Handling Related to Nocturnal Enuresis.

    Science.gov (United States)

    Dossche, L; Raes, A; Hoebeke, P; De Bruyne, P; Vande Walle, J

    2016-01-01

    Although nocturnal polyuria in patients with monosymptomatic enuresis can largely be explained by the decreased nocturnal vasopressin secretion hypothesis, other circadian rhythms in the kidney also seem to have a role. We recently documented an absent day/night rhythm in a subgroup of desmopressin refractory cases. We explore the importance of abnormal circadian rhythm of glomerular filtration and tubular (sodium, potassium) parameters in patients with monosymptomatic enuresis. In this retrospective study of a tertiary enuresis population we collected data subsequent to a standardized screening (International Children's Continence Society questionnaire), 14-day diary for nocturnal enuresis and diuresis, and 24-hour concentration profile. The study population consisted of 139 children with nocturnal enuresis who were 5 years or older. Children with nonmonosymptomatic nocturnal enuresis were used as controls. There was a maintained circadian rhythm of glomerular filtration, sodium, osmotic excretion and diuresis rate in children with monosymptomatic and nonmonosymptomatic nocturnal enuresis, and there was no difference between the 2 groups. Secondary analysis revealed that in patients with nocturnal polyuria (with monosymptomatic or nonmonosymptomatic nocturnal enuresis) circadian rhythm of glomerular filtration, sodium and osmotic excretion, and diuresis rate was diminished in contrast to those without nocturnal polyuria (p enuresis. However, the subgroup with enuresis and nocturnal polyuria has a diminished circadian rhythm of nocturnal diuresis, sodium excretion and glomerular filtration in contrast to children without nocturnal polyuria. This observation cannot be explained by the vasopressin theory alone. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  13. Effects of 24-hour shift work with nighttime napping on circadian rhythm characteristics in ambulance personnel.

    Science.gov (United States)

    Motohashi, Y; Takano, T

    1993-12-01

    Forty-two ambulance personnel engaged in a 24-h shift system participated in a chronobiological field study to study the effects of 24-h shift work on circadian rhythm characteristics. Autorhythmometry of circadian rhythms of oral temperature, right and left grip strengths, and heart rate plus subjective assessment of drowsiness, fatigue, and attention was performed every approximately 4 h except during sleep for 7 days. Cosinor and power spectral analyses were applied to the longitudinal data of each individual. Changes in circadian period different from 24 h of oral temperature, grip strengths, and heart rate plus subjective drowsiness, fatigue, and attention were observed in ambulance personnel. The incidence of circadian periodicity different from 24 h in oral temperature and right and left grip strength was 28.6%, 35.7%, and 47.6%, respectively. The incidence was relatively lower than that of shift workers engaged in a discontinuous 8-h shift system we reported on previously. Working conditions allowing ambulance personnel to nap when not called for emergency (for > 4 h) might contribute to a stabilization of circadian rhythms. Furthermore, long nighttime ambulance service amounting to > 100 min was significantly associated with a high incidence of at least one prominent circadian period among oral temperature and right and left grip strength rhythms different from 24 h. In conclusion, 24-h shift work altered the characteristics of circadian rhythms of ambulance personnel; nighttime naps seemed to have a favorable effect on averting changes in circadian rhythms.

  14. Absence of Circadian Rhythms of Preterm Premature Rupture of Membranes and Preterm Placental Abruption

    Science.gov (United States)

    Luque-Fernandez, Miguel Angel; Ananth, Cande V.; Sanchez, Sixto E.; Qiu, Chun-fang; Hernandez-Diaz, Sonia; Valdimarsdottir, Unnur; Gelaye, Bizu; Williams, Michelle A.

    2014-01-01

    Purpose Data regarding circadian rhythm in the onset of spontaneous preterm premature rupture of membranes (PROM) and placental abruption (PA) cases are conflicting. We modeled the time of onset of preterm PROM and PA cases and examined if the circadian profiles varied based on the gestational age at delivery. Methods We used parametric and nonparametric methods, including trigonometric regression in the framework of generalized linear models, to test the presence of circadian rhythms in the time of onset of preterm PROM and PA cases, among 395 women who delivered a singleton between 2009 and 2010 in Lima, Peru. Results We found a diurnal circadian pattern, with a morning peak at 07h:32’ (95%CI:05h:46’ – 09h:18’) among moderate preterm PROM cases (P-value<0.001), and some evidence of a diurnal circadian periodicity among PA cases in term infants (P-value=0.067). However, we did not find evidence of circadian rhythms in the time of onset of extremely or very preterm PROM (P-value=0.259) and preterm PA (P-value=0.224). Conclusions The circadian rhythms of the time of onset of preterm PROM and PA cases varied based on gestational weeks at delivery. While circadian rhythms were presented among moderate preterm PROM and term PA cases, there was no evidence of circadian rhythms among preterm PA and very or extremely preterm PROM cases, underlying other mechanisms associated with the time of onset. PMID:25453346

  15. The interrelationship between movement and cognition: θ rhythm and the P300 event-related potential.

    Science.gov (United States)

    Shin, Jonghan

    2011-07-01

    The relationship among brain electrophysiological activity, motor activity, and cognition has been a matter of great interest. For example, it has been discussed whether hippocampal theta rhythm reflects motor activity or cognitive activity, whereas it is widely accepted that the P300 event-related potential (ERP) reflects cognitive processes such as updating working memory. Here, we investigated the interrelationships among motor activity, hippocampal theta rhythm, and hippocampal P300 ERP using electrophysiological and behavioral data recorded from rats performing an auditory discrimination task (i.e., the auditory oddball paradigm) in a chamber with and without a running-wheel. We found that the hippocampal theta rhythm generated during locomotion codes information about self-motion, and event-related increases in hippocampal theta rhythm observed when rats performed the auditory discrimination cognitive task reflect a change in motor behavior after learning the cognitive task. Interestingly, the hippocampal P300 ERP occurred coincidently with increases in the power and frequency of hippocampal theta rhythm. In addition, we found that changes in theta rhythm observed during spontaneous wheel running without performing a cognitive task as well as when performing the cognitive task are associated with changes in delta- and gamma-band EEG activities. These major findings are discussed with respect to current hypotheses regarding P300 ERP and theta-, delta-, and gamma-band EEG activities in brain functions. Copyright © 2010 Wiley-Liss, Inc.

  16. Synchronization of cortisol circadian rhythm by the pineal hormone melatonin in untreatable metastatic solid tumor patients and its possible prognostic significance on tumor progression.

    Science.gov (United States)

    Brivio, Fernando; Fumagalli, Luca; Fumagalli, Gabriele; Pescia, Simonetta; Brivio, Rinaldo; Di Fede, Giuseppe; Rovelli, Franco; Lissoni, Paolo

    2010-01-01

    Cancer progression has been associated with neuroendocrine alterations involved in the control of the circadian rhythms, particularly those of cortisol. Moreover, the evidence of an altered cortisol rhythm may predict a poor prognosis in cancer patients. Finally, cancer progression has been proven to be associated with alterations in the pineal gland, which plays a fundamental role in the control of circadian biological rhythms. On this basis, a study was planned to evaluate the effects of a chronic treatment with the pineal hormone melatonin (MLT) in advanced cancer patients with altered cortisol circadian rhythm. The study included 14 untreatable metastatic cancer patients showing alterations of cortisol rhythm. They were treated by MLT at 20 mg/day orally, in the evening, for 3 consecutive months. a normalization of cortisol rhythm was achieved in 4/14 (29%) patients. Moreover, stable disease (SD) was obtained in 6/14 (43%) patients under MLT therapy, whereas the other 8 patients had progressive disease (PD). Finally, the percentage of cortisol rhythm normalization achieved in patients with SD was significantly higher than that observed in patients with PD. These results show that MLT may normalize cortisol rhythm in advanced cancer patients and this effect appears to be associated with SD, thus confirming the negative prognostic significance of cortisol rhythm alterations in cancer.

  17. The generation of respiratory rhythms in birds

    Science.gov (United States)

    Granada, A.; Gabitto, M.; García, G.; Alliende, J.; Méndez, J.; Trevisan, M. A.; Mindlin, G. B.

    2006-11-01

    The generation of precise respiratory rhythms is vital for birds, which must generate specific pressure patterns to perform several activities, song being one of the most demanding ones. These rhythms emerge as the interaction between a peripheral system and a set of neural nuclei which control the action of expiratory and inspiratory muscles. A computational model was proposed recently to account for this interaction. In this work, we describe the set of solutions that this model can display as its parameters are varied, and compare experimental records of air sac pressure patterns with the predictions of the model.

  18. Rate vs. rhythm control and adverse outcomes among European patients with atrial fibrillation.

    Science.gov (United States)

    Purmah, Yanish; Proietti, Marco; Laroche, Cecilé; Mazurek, Michal; Tahmatzidis, Dimitrios; Boriani, Giuseppe; Novo, Salvatore; Lip, Gregory Y H

    2017-02-04

    The impact of rate and rhythm control strategies on outcomes in patients with atrial fibrillation (AF) remains controversial. Our aims were: to report use of rate and rhythm control strategies in European patients from the EURObservational Research Program AF General Pilot Registry. Secondly, to evaluate outcomes according to assigned strategies. Use of pure rate and rhythm control agents was described according to European regions. 1-year follow-up data were reported. Among rate control strategies, beta-blockers were the most commonly used drug. Proportions of patients assigned to rhythm control varied greatly between countries, and amiodarone was the most used rhythm control drug. Of the original 3119 patients, 1036 (33.2%) were assigned to rate control only and 355 (11.4%) to rhythm control only. Patients assigned to a rate control strategy were older (P rate control strategy had higher rates for any thrombo-embolic event (P = 0.0245), cardiovascular death (P = 0.0437), and all-cause death (P rate control strategy was associated with a higher risk for all-cause death (P rate control strategy was independently associated with all-cause death (P = 0.0256). A propensity matched analysis only found a trend for the association between rate control and all-cause death (P = 0.0664). In a European AF patients' cohort, a pure rate control strategy was associated with a higher risk for adverse events at 1-year follow-up, and partially adjusted analysis suggested that rate control independently increased the risk for all-cause death. A fully adjusted propensity score matched analysis found that this association was no longer statistically significant, suggesting an important role of comorbidities in determining the higher risk for all-cause death.

  19. Rhythmic complexity and predictive coding: A novel approach to modeling rhythm and meter perception in music

    Directory of Open Access Journals (Sweden)

    Peter eVuust

    2014-10-01

    Full Text Available Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of predictive coding, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Third, we develop a predictive coding model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard (‘rhythm’ and the brain’s anticipatory structuring of music (‘meter’. Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the predictive coding theory. We argue that musical rhythm exploits the brain’s general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  20. Ultradian rhythm unmasked in the Pdf clock mutant of Drosophila

    Indian Academy of Sciences (India)

    A diverse range of organisms shows physiological and behavioural rhythms with various periods. Extensive studies have been performed to elucidate the molecular mechanisms of circadian rhythms with an approximately 24 h period in both Drosophila and mammals, while less attention has been paid to ultradian rhythms ...

  1. The Features and Training of English Stress and Rhythm

    Science.gov (United States)

    Cai, Cui-yun

    2008-01-01

    In second language learning, to possess a perfect pronunciation, the importance of stress and rhythm should not be ignored. This articles explores the nature of sentence and word stress as well as rhythm, thus putting forward some feasible ways of training and acquiring a good English stress and rhythm in EFLT (English as Foreign Language…

  2. Monkey Lipsmacking Develops Like the Human Speech Rhythm

    Science.gov (United States)

    Morrill, Ryan J.; Paukner, Annika; Ferrari, Pier F.; Ghazanfar, Asif A.

    2012-01-01

    Across all languages studied to date, audiovisual speech exhibits a consistent rhythmic structure. This rhythm is critical to speech perception. Some have suggested that the speech rhythm evolved "de novo" in humans. An alternative account--the one we explored here--is that the rhythm of speech evolved through the modification of rhythmic facial…

  3. EFFECTS OF CIRCADIAN RHYTHM ON BALANCE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Karagul Osman

    2017-09-01

    Full Text Available Introduction. The aim of the study was to examine the effect of circadian rhythm on dynamic balance performance and to determine the role of physical activity level, body temperature, chronotype, and gender in this possible effect. Material and

  4. Ribosomes Dance to a Daily Rhythm.

    Science.gov (United States)

    Iyer, Aishwarya; Grummt, Ingrid

    2017-08-01

    Sinturel et al. demonstrate that feeding-fasting rhythms and light-dark cycles direct daily changes in liver mass and cell size. These feeding-fasting- and light-dark-driven diurnal fluctuations are controlled by an unconventional mechanism that affects ribosome assembly and protein levels during the active phase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Neural Entrainment to Auditory Imagery of Rhythms

    Directory of Open Access Journals (Sweden)

    Haruki Okawa

    2017-10-01

    Full Text Available A method of reconstructing perceived or imagined music by analyzing brain activity has not yet been established. As a first step toward developing such a method, we aimed to reconstruct the imagery of rhythm, which is one element of music. It has been reported that a periodic electroencephalogram (EEG response is elicited while a human imagines a binary or ternary meter on a musical beat. However, it is not clear whether or not brain activity synchronizes with fully imagined beat and meter without auditory stimuli. To investigate neural entrainment to imagined rhythm during auditory imagery of beat and meter, we recorded EEG while nine participants (eight males and one female imagined three types of rhythm without auditory stimuli but with visual timing, and then we analyzed the amplitude spectra of the EEG. We also recorded EEG while the participants only gazed at the visual timing as a control condition to confirm the visual effect. Furthermore, we derived features of the EEG using canonical correlation analysis (CCA and conducted an experiment to individually classify the three types of imagined rhythm from the EEG. The results showed that classification accuracies exceeded the chance level in all participants. These results suggest that auditory imagery of meter elicits a periodic EEG response that changes at the imagined beat and meter frequency even in the fully imagined conditions. This study represents the first step toward the realization of a method for reconstructing the imagined music from brain activity.

  6. Structure and interpretation of rhythm and timing

    NARCIS (Netherlands)

    Honing, H.J.

    2002-01-01

    Rhythm, as it is performed and perceived, is only sparingly addressed in music theory. Existing theories of rhythmic structure are often restricted to music as notated in a score, and as a result are bound to refrain from making statements about music as it is perceived and appreciated by listeners.

  7. Ternary rhythm and the lapse constraint

    NARCIS (Netherlands)

    Elenbaas, N.; Kager, R.W.J.

    2004-01-01

    Ternary rhythmic systems differ from binary systems in stressing every third syllable in a word, rather than every second. Ternary rhythm is well-established for only a small group of languages, including Chugach Alutiiq, Cayuvava, and Estonian, and possibly Winnebago. Nevertheless the stress

  8. Makin' Music: Songs, Rhythm, and Creative Expression.

    Science.gov (United States)

    Lieberstein, Terry

    1996-01-01

    The power of music to create a coherent group is amazing. Music can be used to help focus attention, encourage group unity, involve everyone, and allow creative self-expression. Discusses different song styles, simple rhythm instruments, and song writing. Song-leading tips include song choice, teaching techniques, motions, song sheets, and three…

  9. Working night shifts affects surgeons' biological rhythm

    DEFF Research Database (Denmark)

    Amirian, Ilda; Andersen, Lærke T; Rosenberg, Jacob

    2015-01-01

    prospectively for 4 days: pre call, on call, post call day 1 (PC1), and post call day 2 (PC2). The urinary metabolite of melatonin and cortisol in saliva were measured to assess the circadian rhythm. Sleep and activity were measured by actigraphy. Subjective measures were assessed by the Karolinska Sleepiness...

  10. Circadian rhythms: from genes to behaviour

    Indian Academy of Sciences (India)

    while some researchers have used newly devised tools in molecular genetics to discover more elements of the core clock mechanism and to understand the circadian clockwork at molecular and physiological levels, others continued to probe the key characteristics of circadian rhythms at the whole organism level—a true.

  11. [Circadian rhythm sleep disorders in psychiatric diseases].

    Science.gov (United States)

    Bromundt, Vivien

    2014-11-01

    Circadian rhythm sleep disorders are prevalent among psychiatric patients. This is most probable due to a close relationship between functional disturbances of the internal clock, sleep regulation and mental health. Mechanisms on molecular level of the circadian clock and neurotransmitter signalling are involved in the development of both disorders. Moreover, circadian disorders and psychiatric diseases favour each other by accessory symptoms such as stress or social isolation. Actimetry to objectively quantify the rest-activity cycle and salivary melatonin profiles as marker for the circadian phase help to diagnose circadian rhythm sleep disorders in psychiatric patients. Chronotherapeutics such as bright light therapy, dark therapy, melatonin administration, and wake therapy are used to synchronise and consolidate circadian rhythms and help in the treatment of depression and other psychiatric disorders, but are still neglected in medicine. More molecular to behavioural research is needed for the understanding of the development of circadian disorders and their relationship to psychiatric illnesses. This will help to boost the awareness and treatment of circadian rhythm sleep disorders in psychiatry.

  12. Egg-laying rhythm in Drosophila melanogaster

    Indian Academy of Sciences (India)

    2008-12-31

    Dec 31, 2008 ... not exerted in the mushroom body, a site previously asso- ciated with PKA action on sleep. These results suggest the existence of a novel pathway by which octopamine might regulate circadian rhythms in sleep/wake and egg-laying be- haviour. The ability of octopamine to regulate oviduct con-.

  13. 24-HOUR ACTIVITY RHYTHM AND SLEEP DISTURBANCES IN DEPRESSION AND ANXIETY : A POPULATION-BASED STUDY OF MIDDLE-AGED AND OLDER PERSONS

    NARCIS (Netherlands)

    Luik, Annemarie I; Zuurbier, Lisette A; Direk, Neşe; Hofman, Albert; Van Someren, Eus J W; Tiemeier, Henning

    BACKGROUND: Disturbed circadian rhythms have been associated with depression and anxiety, but it is unclear if disturbances in the 24-hr activity rhythm and sleep are independently and specifically related to these disorders. METHODS: In 1,714 middle-aged and elderly participants of the Rotterdam

  14. 24-Hour Activity Rhythm and Sleep Disturbances in Depression and Anxiety: A Population-Based Study of Middle-Aged and Older Persons

    NARCIS (Netherlands)

    Luik, A.I.; Zuurbier, L.A.; Direk, N.; Hofman, A.; van Someren, E.J.W.; Tiemeier, H.

    2015-01-01

    Background Disturbed circadian rhythms have been associated with depression and anxiety, but it is unclear if disturbances in the 24-hr activity rhythm and sleep are independently and specifically related to these disorders. Methods In 1,714 middle-aged and elderly participants of the Rotterdam

  15. Biological Rhythms During Residence in Polar Regions

    Science.gov (United States)

    2012-01-01

    At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin and/or its metabolite 6-sulfatoxymelatonin (aMT6s) provide probably the best index of circadian (and seasonal) timing. A frequent observation has been a delay of the circadian system in winter. A skeleton photoperiod (2 × 1-h, bright white light, morning and evening) can restore summer timing. A single 1-h pulse of light in the morning may be sufficient. A few people desynchronize from the 24-h day (free-run) and show their intrinsic circadian period, usually >24 h. With regard to general health in polar regions, intermittent reports describe abnormalities in various physiological processes from the point of view of daily and seasonal rhythms, but positive health outcomes are also published. True winter depression (SAD) appears to be rare, although subsyndromal SAD is reported. Probably of most concern are the numerous reports of sleep problems. These have prompted investigations of the underlying mechanisms and treatment interventions. A delay of the circadian system with “normal” working hours implies sleep is attempted at a suboptimal phase. Decrements in sleep efficiency, latency, duration, and quality are also seen in winter. Increasing the intensity of ambient light exposure throughout the day advanced circadian phase and was associated with benefits for sleep: blue-enriched light was slightly more effective than standard white light. Effects on performance remain to be fully investigated. At 75°S, base personnel adapt the circadian system to night work within

  16. Spontaneous Group Synchronization of Movements and Respiratory Rhythms

    Science.gov (United States)

    Vandoni, Matteo; Bernardi, Luciano

    2014-01-01

    We tested whether pre-assigned arm movements performed in a group setting spontaneously synchronized and whether synchronization extended to heart and respiratory rhythms. We monitored arm movements, respiration and electrocardiogram at rest and during spontaneous, music and metronome-associated arm-swinging. No directions were given on whether or how the arm swinging were to be synchronized between participants or with the external cues. Synchronization within 3 groups of 10 participants studied collectively was compared with pseudo-synchronization of 3 groups of 10 participants that underwent an identical protocol but in an individual setting. Motor synchronization was found to be higher in the collective groups than in the individuals for the metronome-associated condition. On a repetition of the protocol on the following day, motor synchronization in the collective groups extended to the spontaneous, un-cued condition. Breathing was also more synchronized in the collective groups than in the individuals, particularly at rest and in the music-associated condition. Group synchronization occurs without explicit instructions, and involves both movements and respiratory control rhythms. PMID:25216280

  17. From Biological Rhythms to Social Rhythms: Physiological Precursors of Mother-Infant Synchrony

    Science.gov (United States)

    Feldman, Ruth

    2006-01-01

    Links between neonatal biological rhythms and the emergence of interaction rhythms were examined in 3 groups (N=71): high-risk preterms (HR; birth weight less than 1,000 g), low-risk preterms (LR; birth weight=1,700-1,850 g), and full-term (FT) infants. Once a week for premature infants and on the 2nd day for FT infants, sleep-wake cyclicity was…

  18. Sleep and circadian rhythms in humans.

    Science.gov (United States)

    Czeisler, C A; Gooley, J J

    2007-01-01

    During the past 50 years, converging evidence reveals that the fundamental properties of the human circadian system are shared in common with those of other organisms. Concurrent data from multiple physiological rhythms in humans revealed that under some conditions, rhythms oscillated at different periods within the same individuals and led to the conclusion 30 years ago that the human circadian system was composed of multiple oscillators organized hierarchically; this inference has recently been confirmed using molecular techniques in species ranging from unicellular marine organisms to mammals. Although humans were once thought to be insensitive to the resetting effects of light, light is now recognized as the principal circadian synchronizer in humans, capable of eliciting weak (Type 1) or strong (Type 0) resetting, depending on stimulus strength and timing. Realization that circadian photoreception could be maintained in the absence of sight was first recognized in blind humans, as was the property of adaptation of the sensitivity of circadian photoreception to prior light history. In sighted humans, the intrinsic circadian period is very tightly distributed around approximately 24.2 hours and exhibits aftereffects of prior entrainment. Phase angle of entrainment is dependent on circadian period, at least in young adults. Circadian pacemakers in humans drive daily variations in many physiologic and behavioral variables, including circadian rhythms in alertness and sleep propensity. Under entrained conditions, these rhythms interact with homeostatic regulation of the sleep/wake cycle to determine the ability to sustain vigilance during the day and to sleep at night. Quantitative understanding of the fundamental properties of the multioscillator circadian system in humans and their interaction with sleep/wake homeostasis has many applications to health and disease, including the development of treatments for circadian rhythm and sleep disorders.

  19. Characterisation of circadian rhythms of various duckweeds.

    Science.gov (United States)

    Muranaka, T; Okada, M; Yomo, J; Kubota, S; Oyama, T

    2015-01-01

    The plant circadian clock controls various physiological phenomena that are important for adaptation to natural day-night cycles. Many components of the circadian clock have been identified in Arabidopsis thaliana, the model plant for molecular genetic studies. Recent studies revealed evolutionary conservation of clock components in green plants. Homologues of clock-related genes have been isolated from Lemna gibba and Lemna aequinoctialis, and it has been demonstrated that these homologues function in the clock system in a manner similar to their functioning in Arabidopsis. While clock components are widely conserved, circadian phenomena display diversity even within the Lemna genus. In order to survey the full extent of diversity in circadian rhythms among duckweed plants, we characterised the circadian rhythms of duckweed by employing a semi-transient bioluminescent reporter system. Using a particle bombardment method, circadian bioluminescent reporters were introduced into nine strains representing five duckweed species: Spirodela polyrhiza, Landoltia punctata, Lemna gibba, L. aequinoctialis and Wolffia columbiana. We then monitored luciferase (luc+) reporter activities driven by AtCCA1, ZmUBQ1 or CaMV35S promoters under entrainment and free-running conditions. Under entrainment, AtCCA1::luc+ showed similar diurnal rhythms in all strains. This suggests that the mechanism of biological timing under day-night cycles is conserved throughout the evolution of duckweeds. Under free-running conditions, we observed circadian rhythms of AtCCA1::luc+, ZmUBQ1::luc+ and CaMV35S::luc+. These circadian rhythms showed diversity in period length and sustainability, suggesting that circadian clock mechanisms are somewhat diversified among duckweeds. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  20. Biologic rhythms derived from Siberian mammoths' hairs.

    Science.gov (United States)

    Spilde, Mike; Lanzirotti, Antonio; Qualls, Clifford; Phillips, Genevieve; Ali, Abdul-Mehdi; Agenbroad, Larry; Appenzeller, Otto

    2011-01-01

    Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ∼31 cms/year and ∼16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  1. Biologic rhythms derived from Siberian mammoths' hairs.

    Directory of Open Access Journals (Sweden)

    Mike Spilde

    Full Text Available Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ∼31 cms/year and ∼16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios, which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  2. Naturally occurring circadian rhythm and sleep duration are related to executive functions in early adulthood.

    Science.gov (United States)

    Kuula, Liisa; Pesonen, Anu-Katriina; Heinonen, Kati; Kajantie, Eero; Eriksson, Johan Gunnar; Andersson, Sture; Lano, Aulikki; Lahti, Jari; Wolke, Dieter; Räikkönen, Katri

    2017-07-20

    Experimental sleep deprivation studies suggest that insufficient sleep and circadian misalignment associates with poorer executive function. It is not known whether this association translates to naturally occurring sleep patterns. A total of 512 of full-term-born members of the Arvo Ylppö Longitudinal Study [mean age = 25.3, standard deviation (SD) = 0.65] (44.3% men) wore actigraphs to define sleep duration, its irregularity and circadian rhythm (sleep mid-point) during a 1-week period (mean 6.9 nights, SD = 1.7). Performance-based executive function was assessed with the Trail-Making Test, Conners' Continuous Performance Test and Stroop. The self-rated adult version of Behavior Rating Inventory of Executive Function was used to assess trait-like executive function. We found that performance-based and self-reported trait-like executive function correlated only modestly (all correlations ≤0.17). Shorter sleep duration associated with more commission errors. Later circadian rhythm associated with poorer trait-like executive function, as indicated by the Brief Metacognitive Index and the Behavior Regulation Index. Those belonging to the group with the most irregular sleep duration performed slower than others in the Trail-Making Test Part A. All associations were adjusted for sex, age, socioeconomic status and body mass index. In conclusion, naturally occurring insufficient sleep and later circadian rhythm showed modest associations with poorer executive function. Shorter habitual sleep duration was associated with lower scores of performance-based tests of executive function, and later circadian rhythm was associated mainly with poorer trait-like executive function characteristics. Our findings suggest additionally that sleep duration and circadian rhythm associate with different domains of executive function, and there are no additive effects between the two. © 2017 European Sleep Research Society.

  3. Disruption of gene expression rhythms in mice lacking secretory vesicle proteins IA-2 and IA-2β

    OpenAIRE

    Punia, Sohan; Rumery, Kyle K.; Yu, Elizabeth A.; Christopher M Lambert; Notkins, Abner L.; David R Weaver

    2012-01-01

    Insulinoma-associated protein (IA)-2 and IA-2β are transmembrane proteins involved in neurotransmitter secretion. Mice with targeted disruption of both IA-2 and IA-2β (double-knockout, or DKO mice) have numerous endocrine and physiological disruptions, including disruption of circadian and diurnal rhythms. In the present study, we have assessed the impact of disruption of IA-2 and IA-2β on molecular rhythms in the brain and peripheral oscillators. We used in situ hybridization to assess molec...

  4. [Seasons, circadian rhythms, sleep and suicidal behaviors vulnerability].

    Science.gov (United States)

    Benard, V; Geoffroy, P A; Bellivier, F

    2015-09-01

    Suicidal behaviors are common in the general population and are so a major public health problem. In order to improve suicide prevention and to reduce the mortality by suicide, it appears essential to better identify suicide risk factors. Seasonality, circadian rhythms and sleep abnormalities have been already associated with numerous psychiatric disorders. This review aimed to characterize the associations between seasonality, circadian rhythms, sleep and suicidal behaviors including suicide attempts and completed suicides. We conducted a literature search between 1973 and 2015 in PubMed databases using the following terms: ("suicide" OR "suicidality" OR "suicide attempts" OR "suicidal behavior") AND ("circadian rhythms" OR "seasons" OR "sleep"). Many studies confirm a specific seasonality for suicide with a higher peak of suicides in spring for both sex and a lower peak in autumn especially for women. This distribution seems to correlate with depressive symptoms (especially for the autumn peak), gender and different types of suicide. Regarding gender and type of suicide differences, males more commonly commit violent suicide with a higher rate of suicides in spring. Suicide behaviors appear to be influenced by climatic and biological factors like sunshine, daylight cycles, temperature, air pollutants, viruses, parasites and aeroallergens. Circadian variations exist in suicide rates depending on age with a morning peak for elder and an evening peak for youth. In addition, completed suicide peak in early morning whereas suicide attempts peak rather in later afternoon. Several biomarkers dysregulation like melatonin, serotonin and cortisol may be implicated in suicide circadian variations. Furthermore, specific sleep disorders like insomnia, nightmares and sleep deprivation are common risk factors of suicide and possibly independently of the presence of depressive symptoms. Finally, the efficacy of chronotherapeutics (such as luminotherapy, dark therapy, sleep

  5. The sensory-motor theory of rhythm and beat induction 20 years on: A new synthesis and future perspectives.

    Directory of Open Access Journals (Sweden)

    Neil Philip Todd

    2015-08-01

    Full Text Available Some 20 years ago Todd and colleagues proposed that rhythm perception is mediated by the conjunction of a sensory representation of the auditory input and a motor representation of the body (Todd 1994, 1995, and that a sense of motion from sound is mediated by the vestibular system (Todd 1992, 1993. These ideas were developed into a sensory-motor theory of rhythm and beat induction (Todd et al. 1999. A neurological substrate was proposed which might form the biological basis of the theory (Todd et al. 2002. The theory was implemented as a computational model and a number of experiments conducted to test it. In the following time there have been several key developments. One is the demonstration that the vestibular system is primal to rhythm perception, and in related work several experiments have provided further evidence that rhythm perception is body dependent. Another is independent advances in imaging, which have revealed the brain areas associated with both vestibular processing and rhythm perception. A third is the finding that vestibular receptors contribute to auditory evoked potentials (Todd et al. 2014ab. These behavioural and neurobiological developments demand a theoretical overview which could provide a new synthesis over the domain of rhythm perception. In this paper we suggest four propositions as the basis for such a synthesis. (1 Rhythm perception is a form of vestibular perception; (2 Rhythm perception evokes both external and internal guidance of somatotopic representations; (3 A link from the limbic system to the internal guidance pathway mediates the dance habit; (4 The vestibular reward mechanism is innate. The new synthesis provides an explanation for a number of phenomena not often considered by rhythm researchers. We discuss these along with possible computational implementations and alternative models and propose a number of new directions for future research.

  6. Period concatenation underlies interactions between gamma and beta rhythms in neocortex

    Directory of Open Access Journals (Sweden)

    Anita K Roopun

    2008-04-01

    Full Text Available The neocortex generates rhythmic electrical activity over a frequency range covering many decades. Specific cognitive and motor states are associated with oscillations in discrete frequency bands within this range, but it is not known whether interactions and transitions between distinct frequencies are of functional importance. When coexpressed rhythms have frequencies that differ by a factor of two or more interactions can be seen in terms of phase synchronization. Larger frequency differences can result in interactions in the form of nesting of faster frequencies within slower ones by a process of amplitude modulation. It is not known how coexpressed rhythms, whose frequencies differ by less than a factor of two may interact. Here we show that two frequencies (gamma – 40 Hz and beta2 – 25 Hz, coexpressed in superficial and deep cortical laminae with low temporal interaction, can combine to generate a third frequency (beta1 – 15 Hz showing strong temporal interaction. The process occurs via period concatenation, with basic rhythm-generating microcircuits underlying gamma and beta2 rhythms forming the building blocks of the beta1 rhythm by a process of addition. The mean ratio of adjacent frequency components was a constant – approximately the golden mean – which served to both minimize temporal interactions, and permit multiple transitions, between frequencies. The resulting temporal landscape may provide a framework for multiplexing – parallel information processing on multiple temporal scales.

  7. Crosslinguistic Application of English-Centric Rhythm Descriptors in Motor Speech Disorders

    Science.gov (United States)

    Liss, Julie M.; Utianski, Rene; Lansford, Kaitlin

    2014-01-01

    Background Rhythmic disturbances are a hallmark of motor speech disorders, in which the motor control deficits interfere with the outward flow of speech and by extension speech understanding. As the functions of rhythm are language-specific, breakdowns in rhythm should have language-specific consequences for communication. Objective The goals of this paper are to (i) provide a review of the cognitive- linguistic role of rhythm in speech perception in a general sense and crosslinguistically; (ii) present new results of lexical segmentation challenges posed by different types of dysarthria in American English, and (iii) offer a framework for crosslinguistic considerations for speech rhythm disturbances in the diagnosis and treatment of communication disorders associated with motor speech disorders. Summary This review presents theoretical and empirical reasons for considering speech rhythm as a critical component of communication deficits in motor speech disorders, and addresses the need for crosslinguistic research to explore language-universal versus language-specific aspects of motor speech disorders. PMID:24157596

  8. Analysis of gene regulatory networks in the mammalian circadian rhythm.

    Directory of Open Access Journals (Sweden)

    Jun Yan

    2008-10-01

    Full Text Available Circadian rhythm is fundamental in regulating a wide range of cellular, metabolic, physiological, and behavioral activities in mammals. Although a small number of key circadian genes have been identified through extensive molecular and genetic studies in the past, the existence of other key circadian genes and how they drive the genomewide circadian oscillation of gene expression in different tissues still remains unknown. Here we try to address these questions by integrating all available circadian microarray data in mammals. We identified 41 common circadian genes that showed circadian oscillation in a wide range of mouse tissues with a remarkable consistency of circadian phases across tissues. Comparisons across mouse, rat, rhesus macaque, and human showed that the circadian phases of known key circadian genes were delayed for 4-5 hours in rat compared to mouse and 8-12 hours in macaque and human compared to mouse. A systematic gene regulatory network for the mouse circadian rhythm was constructed after incorporating promoter analysis and transcription factor knockout or mutant microarray data. We observed the significant association of cis-regulatory elements: EBOX, DBOX, RRE, and HSE with the different phases of circadian oscillating genes. The analysis of the network structure revealed the paths through which light, food, and heat can entrain the circadian clock and identified that NR3C1 and FKBP/HSP90 complexes are central to the control of circadian genes through diverse environmental signals. Our study improves our understanding of the structure, design principle, and evolution of gene regulatory networks involved in the mammalian circadian rhythm.

  9. Endogenous cortical rhythms determine cerebral specialization for speech perception and production

    DEFF Research Database (Denmark)

    Giraud, Anne-Lise; Kleinschmidt, Andreas; Poeppel, David

    2007-01-01

    Across multiple timescales, acoustic regularities of speech match rhythmic properties of both the auditory and motor systems. Syllabic rate corresponds to natural jaw-associated oscillatory rhythms, and phonemic length could reflect endogenous oscillatory auditory cortical properties. Hemispheric...... lateralization for speech could result from an asymmetry of cortical tuning, with left and right auditory areas differentially sensitive to spectro-temporal features of speech. Using simultaneous electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) recordings from humans, we show......, indicating coupling between temporal properties of speech perception and production. These data show that endogenous cortical rhythms provide temporal and spatial constraints on the neuronal mechanisms underlying speech perception and production....

  10. The circadian gene mPer2 regulates the daily rhythm of IFN-gamma.

    Science.gov (United States)

    Arjona, Alvaro; Sarkar, Dipak K

    2006-09-01

    Circadian and daily rhythms regulate many aspects of physiology and behavior. Although a growing number of studies suggest that circadian disruptions may render organisms more susceptible to infection and cancer, the molecular links between the circadian system and the immune system are largely unknown. Here we report that mice carrying a loss-of-function mutation in the Per2 gene, a key component of the molecular circadian clock, lacked the physiologic daily rhythm of interferon-gamma (IFN-gamma) mRNA and protein expression in the spleen. These observations were associated with a significant alteration in the expression of canonical clock genes. In addition, Per2 mutant mice failed to show a daily rhythm in IFN-gamma serum levels, which were significantly lower than those determined in wild-type mice during the early light period. These findings provide novel evidence for a direct circadian regulation of IFN-gamma, a critical cytokine modulating the immune response.

  11. An Overview of Monthly Rhythms and Clocks

    Directory of Open Access Journals (Sweden)

    Florian Raible

    2017-05-01

    Full Text Available Organisms have evolved to cope with geophysical cycles of different period lengths. In this review, we focus on the adaptations of animals to the lunar cycle, specifically, on the occurrence of biological rhythms with monthly (circalunar or semi-monthly (circasemilunar period lengths. Systematic experimental investigation, starting in the early twentieth century, has allowed scientists to distinguish between mythological belief and scientific facts concerning the influence of the lunar cycle on animals. These studies revealed that marine animals of various taxa exhibit circalunar or circasemilunar reproductive rhythms. Some of these rely on endogenous oscillators (circalunar or circasemilunar clocks, whereas others are directly driven by external cues, such as the changes in nocturnal illuminance. We review current insight in the molecular and cellular mechanisms involved in circalunar rhythms, focusing on recent work in corals, annelid worms, midges, and fishes. In several of these model systems, the transcript levels of some core circadian clock genes are affected by both light and endogenous circalunar oscillations. How these and other molecular changes relate to the changes in physiology or behavior over the lunar cycle remains to be determined. We further review the possible relevance of circalunar rhythms for terrestrial species, with a particular focus on mammalian reproduction. Studies on circalunar rhythms of conception or birth rates extend to humans, where the lunar cycle was suggested to also affect sleep and mental health. While these reports remain controversial, factors like the increase in “light pollution” by artificial light might contribute to discrepancies between studies. We finally discuss the existence of circalunar oscillations in mammalian physiology. We speculate that these oscillations could be the remnant of ancient circalunar oscillators that were secondarily uncoupled from a natural entrainment mechanism, but

  12. High beat-to-beat blood pressure variability in atrial fibrillation compared to sinus rhythm.

    Science.gov (United States)

    Olbers, Joakim; Gille, Adam; Ljungman, Petter; Rosenqvist, Mårten; Östergren, Jan; Witt, Nils

    2018-02-07

    Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, not entirely explained by thromboembolism. The underlying mechanisms for this association are largely unknown. Similarly, high blood pressure (BP) increases the risk for cardiovascular events. Despite this the interplay between AF and BP is insufficiently studied. The purpose of this study was to examine and quantify the beat-to-beat blood pressure variability in patients with AF in comparison to a control group of patients with sinus rhythm. We studied 33 patients - 21 in atrial fibrillation and 12 in sinus rhythm - undergoing routine coronary angiography. Invasive blood pressure was recorded at three locations: radial artery, brachial artery and ascending aorta. Blood pressure variability, defined as average beat-to-beat blood pressure difference, was calculated for systolic and diastolic blood pressure at each site. We observed a significant difference (p blood pressure variability between the atrial fibrillation and sinus rhythm groups at all locations. Systolic blood pressure variability roughly doubled in the atrial fibrillation group compared to the sinus rhythm group (4.9 and 2.4 mmHg respectively). Diastolic beat-to-beat blood pressure variability was approximately 6 times as high in the atrial fibrillation group compared to the sinus rhythm group (7.5 and 1.2 mmHg respectively). No significant difference in blood pressure variability was seen between measurement locations. Beat-to-beat blood pressure variability in patients with atrial fibrillation was substantially higher than in patients with sinus rhythm. Hemodynamic effects of this beat-to-beat variation in blood pressure may negatively affect vascular structure and function, which may contribute to the increased cardiovascular morbidity and mortality seen in patients with atrial fibrillation.

  13. Food-entrained feeding and locomotor circadian rhythms in rats under different lighting conditions.

    Science.gov (United States)

    Lax, P; Zamora, S; Madrid, J A

    1999-05-01

    It has been suggested that two endogenous timekeeping systems, a light-entrainable pacemaker (LEP) and a food-entrainable pacemaker (FEP), control circadian rhythms. To understand the function and interaction between these two mechanisms better, we studied two behavioral circadian rhythmicities, feeding and locomotor activity, in rats exposed to two conflicting zeitgebers, food restriction and light-dark cycles. For this, the food approaches and wheel-running activity of rats kept under light-dark (LD) 12:12, constant darkness (DD), or constant light (LL) conditions and subjected to different scheduled feeding patterns were continuously recorded. To facilitate comparison of the results obtained under the different lighting conditions, the period of the feeding cycles was set in all three cases about 1h less than the light-entrained or free-running circadian rhythms. The results showed that, depending on the lighting conditions, some components of the feeding and wheel-running circadian rhythms could be entrained by food pulses, while others retained their free-running or light-entrained state. Under LD, food pulses had little influence on the light-entrained feeding and locomotor rhythms. Under DD, relative coordination between free-running and food-associated rhythms may appear. In both cases, the feeding activity associated with the food pulses could be divided into a prominent phase-dependent peak of activity within the period of food availability and another afterward. Wheel-running activity mainly followed the food pulses. Under LL conditions, the food-entrained activity consisted mainly of feeding and wheel-running anticipatory activity. The results provide new evidence that lighting conditions influence the establishment and persistence of food-entrained circadian rhythms in rats. The existence of two coupled pacemakers, LEP and FEP, or a multioscillatory LEP may both explain our experimental results.

  14. Effects of nocturnal hemodialysis on melatonin rhythm and sleep-wake behavior: an uncontrolled trial

    NARCIS (Netherlands)

    Koch, B.C.P.; Hagen, E.C.; Nagtegaal, J.E.; Boringa, J.B.S.; Kerkhof, G.A.; ter Wee, P.M.

    2009-01-01

    Background: End-stage renal disease and its treatment are associated with sleep disturbances such as deterioration of the circadian sleep-wake pattern. Melatonin rhythm, which has an important role in this pattern, is disturbed. The nocturnal melatonin surge is absent in this population. Whether

  15. 24-HOUR ACTIVITY RHYTHM AND SLEEP DISTURBANCES IN DEPRESSION AND ANXIETY: A POPULATION-BASED STUDY OF MIDDLE-AGED AND OLDER PERSONS.

    Science.gov (United States)

    Luik, Annemarie I; Zuurbier, Lisette A; Direk, Neşe; Hofman, Albert; Van Someren, Eus J W; Tiemeier, Henning

    2015-09-01

    Disturbed circadian rhythms have been associated with depression and anxiety, but it is unclear if disturbances in the 24-hr activity rhythm and sleep are independently and specifically related to these disorders. In 1,714 middle-aged and elderly participants of the Rotterdam Study, we collected actigraphy recordings of at least 96 hr (138 ± 14 hr, mean ± standard deviation). Activity rhythms were quantified calculating the fragmentation of the rhythm, stability of the rhythm over days, and timing of the rhythm. Total sleep time, sleep onset latency, and wake after sleep onset were also estimated with actigraphy. Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression scale, persons with clinically relevant depressive symptoms were interviewed to diagnose DSM-IV-depressive disorder. Anxiety disorders were determined with the Munich version of the Composite International Diagnostic Interview. More fragmented rhythms were associated with clinically relevant depressive symptoms (odds ratio (OR): 1.27, 95% confidence interval (CI): 1.04;1.54) and anxiety disorders (OR: 1.39, 95% CI: 1.14;1.70) after covariate adjustment. Less stable rhythms, longer sleep onset latency, and more wake after sleep onset were related to clinically relevant depressive symptoms or anxiety disorders only if not adjusted for covariates and other activity rhythm and sleep indicators. Our study in middle-aged and elderly persons suggests that fragmentation of the 24-hr activity rhythm is associated with depression and anxiety. Moreover, this association also largely accounts for the effect of disturbed sleep on these psychiatric disorders. © 2015 Wiley Periodicals, Inc.

  16. Posttranscriptional mechanisms in controlling eukaryotic circadian rhythms.

    Science.gov (United States)

    Zhang, Lin; Weng, Wenya; Guo, Jinhu

    2011-05-20

    The circadian clock is essential in almost all living organisms to synchronise biochemical, metabolic, physiological and behavioural cycles to daily changing environmental factors. In a highly conserved fashion, the circadian clock is primarily controlled by multiple positive and negative molecular circuitries that control gene expression. More recently, research in Neurospora and other eukaryotes has uncovered the involvement of additional regulatory components that operate at the posttranslational level to fine tune the circadian system. Though it remains poorly understood, a growing body of evidence has shown that posttranscriptional regulation controls the expression of both circadian oscillator and output gene transcripts at a number of different steps. This regulation is crucial for driving and maintaining robust circadian rhythms. Here we review recent advances in circadian rhythm research at the RNA level. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. [Impact of sleep debt on physiological rhythms].

    Science.gov (United States)

    Spiegel, K; Leproult, R; Van Cauter, E

    2003-11-01

    Sleep loss due to voluntary bedtime curtailment has become a hallmark of modern society. Even though sleep deprivation in rodents has been shown to result in death, it was until a few years ago thought that sleep loss results in increased sleepiness and decreased cognitive performance but has little or no adverse effects on human health. We measured sleep and 24-hour hormonal profiles in 11 healthy young males after 6 days of sleep restriction (4-hour bedtime) and after 6 days of sleep recovery (12-hour bedtime). At the end of sleep restriction, we observed reduced amounts of slow wave sleep (SWS) and rapid eye movement (REM) sleep and an alteration in the temporal distribution of these sleep stages, i.e. an increased pressure for REM sleep at the beginning of the sleep period and a decrease in the amount of slow wave activity (SWA) during the first sleep cycle. These later abnormalities are usually observed in depression. In addition, numerous alterations in the 24-hour hormonal profiles were observed in the state of sleep debt. The amount of melatonin secreted was reduced because of a delay in the onset of the nocturnal secretion and a reduction in the value of the acrophase. If the overall 24-hour cortisol profile was preserved, sleep restriction was associated with increased cortisol levels in late afternoon and evening hours and the duration of the quiescent period was reduced. The 24-hour mean TSH levels were reduced and the nocturnal TSH elevation was markedly dampened, most likely as a result of elevated levels of thyroid hormones. The acrophase of the 24-hour leptin profile occurred earlier, the amplitude of the rhythm and the overall mean levels were reduced. The nocturnal elevation of prolactin levels was abrupt but of short duration and the 24-hour mean levels were decreased. A pulse of growth hormone occurred prior to sleep onset, therefore affecting SWA distribution at the beginning of the sleep period. Since these alterations are qualitatively and

  18. Biological Rhythms During Residence in Polar Regions

    OpenAIRE

    Arendt, Josephine

    2012-01-01

    At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin ...

  19. Circadian Rhythms, Sleep, and Disorders of Aging

    OpenAIRE

    Mattis, Joanna; Sehgal, Amita

    2016-01-01

    Sleep:wake cycles are known to be disrupted in people with neurodegenerative disorders. These findings are now supported by data from animal models for some of these disorders, raising the question of whether the disrupted sleep/circadian regulation contributes to the loss of neural function. As circadian rhythms and sleep consolidation also break down with normal aging, changes in these may be part of what makes aging a risk factor for disorders like Alzheimer's disease. Mechanisms underlyin...

  20. Circadian rhythms of women with fibromyalgia

    Science.gov (United States)

    Klerman, E. B.; Goldenberg, D. L.; Brown, E. N.; Maliszewski, A. M.; Adler, G. K.

    2001-01-01

    Fibromyalgia syndrome is a chronic and debilitating disorder characterized by widespread nonarticular musculoskeletal pain whose etiology is unknown. Many of the symptoms of this syndrome, including difficulty sleeping, fatigue, malaise, myalgias, gastrointestinal complaints, and decreased cognitive function, are similar to those observed in individuals whose circadian pacemaker is abnormally aligned with their sleep-wake schedule or with local environmental time. Abnormalities in melatonin and cortisol, two hormones whose secretion is strongly influenced by the circadian pacemaker, have been reported in women with fibromyalgia. We studied the circadian rhythms of 10 women with fibromyalgia and 12 control healthy women. The protocol controlled factors known to affect markers of the circadian system, including light levels, posture, sleep-wake state, meals, and activity. The timing of the events in the protocol were calculated relative to the habitual sleep-wake schedule of each individual subject. Under these conditions, we found no significant difference between the women with fibromyalgia and control women in the circadian amplitude or phase of rhythms of melatonin, cortisol, and core body temperature. The average circadian phases expressed in hours posthabitual bedtime for women with and without fibromyalgia were 3:43 +/- 0:19 and 3:46 +/- 0:13, respectively, for melatonin; 10:13 +/- 0:23 and 10:32 +/- 0:20, respectively for cortisol; and 5:19 +/- 0:19 and 4:57 +/- 0:33, respectively, for core body temperature phases. Both groups of women had similar circadian rhythms in self-reported alertness. Although pain and stiffness were significantly increased in women with fibromyalgia compared with healthy women, there were no circadian rhythms in either parameter. We suggest that abnormalities in circadian rhythmicity are not a primary cause of fibromyalgia or its symptoms.

  1. Peroxiredoxins are conserved markers of circadian rhythms

    Science.gov (United States)

    Edgar, Rachel S.; Green, Edward W.; Zhao, Yuwei; van Ooijen, Gerben; Olmedo, Maria; Qin, Ximing; Xu, Yao; Pan, Min; Valekunja, Utham K.; Feeney, Kevin A.; Maywood, Elizabeth S.; Hastings, Michael H.; Baliga, Nitin S.; Merrow, Martha; Millar, Andrew J.; Johnson, Carl H.; Kyriacou, Charalambos P.; O’Neill, John S.; Reddy, Akhilesh B.

    2012-01-01

    Summary Cellular life emerged ~3.7 billion years ago. With scant exception, terrestrial organisms have evolved under predictable daily cycles due to the Earth’s rotation. The advantage conferred upon organisms that anticipate such environmental cycles has driven the evolution of endogenous circadian rhythms that tune internal physiology to external conditions. The molecular phylogeny of mechanisms driving these rhythms has been difficult to dissect because identified clock genes and proteins are not conserved across the domains of life: Bacteria, Archaea and Eukaryota. Here we show that oxidation-reduction cycles of peroxiredoxin proteins constitute a universal marker for circadian rhythms in all domains of life, by characterising their oscillations in a variety of model organisms. Furthermore, we explore the interconnectivity between these metabolic cycles and transcription-translation feedback loops of the clockwork in each system. Our results suggest an intimate co-evolution of cellular time-keeping with redox homeostatic mechanisms following the Great Oxidation Event ~2.5 billion years ago. PMID:22622569

  2. Electroencephalogram base rhythm in AIDS patients

    Directory of Open Access Journals (Sweden)

    G. Fernandes do Prado

    1993-06-01

    Full Text Available We studied the EEG of 73 patients diagnosed with HIV infection, with or without secondary complications. Sixty-eight belonged to CDC (Center for Disease Control group IV and 38 presented signs or symptoms of encephalic neurological impairment. Rhytms constituting base activity were alpha (65.75%, beta (13.70%, theta (12.33%, and delta (8.22%. The alpha rhythm presented two modes: slow (8 to 9 Hz in 25/48 or 52.08% of the cases and not-slow (>9 to 13 Hz in 23/48 or 47.92% of the cases. The alpha slow-mode has been observed in about 10 to 15% of the normal population, with the 8 Hz frequency being found in only 1% of the normal adult population, which suggests that in some manner HIV is implicated in the slowing-down of the EEG base rhythm in AIDS patients. The patients from CDC group IV with encephalic neurological involvement presented a base rhythm significantly lower than those with non-encephalic involvement or the absence of neurological impairment.

  3. Tonic neuromodulation of the inspiratory rhythm generator

    Directory of Open Access Journals (Sweden)

    Fernando ePeña-Ortega

    2012-07-01

    Full Text Available The generation of neural network dynamics relies on the interactions between the intrinsic and synaptic properties of their neural components. Moreover, neuromodulators allow networks to change these properties and adjust their activity to specific challenges. Endogenous continuous (tonic neuromodulation can regulate and sometimes be indispensible for networks to produce basal activity. This seems to be the case for the inspiratory rhythm generator located in the pre-Bötzinger complex (preBötC. This neural network is necessary and sufficient for generating inspiratory rhythms. The preBötC produces normal respiratory activity (eupnea as well as sighs under normoxic conditions, and it generates gasping under hypoxic conditions after a reconfiguration process. The reconfiguration leading to gasping generation involves changes of synaptic and intrinsic properties that can be mediated by several neuromodulators. Over the past years, it has been shown that endogenous continuous neuromodulation of the preBötC may involve the continuous action of amines and peptides on extrasynaptic receptors. I will summarize the findings supporting the role of endogenous continuous neuromodulation in the generation and regulation of different inspiratory rhythms, exploring the possibility that these neuromodulatory actions involve extrasynaptic receptors along with evidence of glial modulation of preBötC activity.

  4. Brain networks for integrative rhythm formation.

    Directory of Open Access Journals (Sweden)

    Michael H Thaut

    2008-05-01

    Full Text Available Performance of externally paced rhythmic movements requires brain and behavioral integration of sensory stimuli with motor commands. The underlying brain mechanisms to elaborate beat-synchronized rhythm and polyrhythms that musicians readily perform may differ. Given known roles in perceiving time and repetitive movements, we hypothesized that basal ganglia and cerebellar structures would have greater activation for polyrhythms than for on-the-beat rhythms.Using functional MRI methods, we investigated brain networks for performing rhythmic movements paced by auditory cues. Musically trained participants performed rhythmic movements at 2 and 3 Hz either at a 1:1 on-the-beat or with a 3:2 or a 2:3 stimulus-movement structure. Due to their prior musical experience, participants performed the 3:2 or 2:3 rhythmic movements automatically. Both the isorhythmic 1:1 and the polyrhythmic 3:2 or 2:3 movements yielded the expected activation in contralateral primary motor cortex and related motor areas and ipsilateral cerebellum. Direct comparison of functional MRI signals obtained during 3:2 or 2:3 and on-the-beat rhythms indicated activation differences bilaterally in the supplementary motor area, ipsilaterally in the supramarginal gyrus and caudate-putamen and contralaterally in the cerebellum.The activated brain areas suggest the existence of an interconnected brain network specific for complex sensory-motor rhythmic integration that might have specificity for elaboration of musical abilities.

  5. Circadian rhythm disruption in cancer biology.

    Science.gov (United States)

    Savvidis, Christos; Koutsilieris, Michael

    2012-12-06

    Circadian rhythms show universally a 24-h oscillation pattern in metabolic, physiological and behavioral functions of almost all species. This pattern is due to a fundamental adaptation to the rotation of Earth around its own axis. Molecular mechanisms of generation of circadian rhythms organize a biochemical network in suprachiasmatic nucleus and peripheral tissues, building cell autonomous clock pacemakers. Rhythmicity is observed in transcriptional expression of a wide range of clock-controlled genes that regulate a variety of normal cell functions, such as cell division and proliferation. Desynchrony of this rhythmicity seems to be implicated in several pathologic conditions, including tumorigenesis and progression of cancer. In 2007, the International Agency for Research on Cancer (IARC) categorized "shiftwork that involves circadian disruption [as] probably carcinogenic to humans" (Group 2A in the IARC classification system of carcinogenic potency of an agentagent) (Painting, Firefighting, and Shiftwork; IARC; 2007). This review discusses the potential relation between disruptions of normal circadian rhythms with genetic driving machinery of cancer. Elucidation of the role of clockwork disruption, such as exposure to light at night and sleep disruption, in cancer biology could be important in developing new targeted anticancer therapies, optimizing individualized chronotherapy and modifying lighting environment in workplaces or homes.

  6. Rhythm perception and production predict reading abilities in developmental dyslexia.

    Science.gov (United States)

    Flaugnacco, Elena; Lopez, Luisa; Terribili, Chiara; Zoia, Stefania; Buda, Sonia; Tilli, Sara; Monasta, Lorenzo; Montico, Marcella; Sila, Alessandra; Ronfani, Luca; Schön, Daniele

    2014-01-01

    Rhythm organizes events in time and plays a major role in music, but also in the phonology and prosody of a language. Interestingly, children with developmental dyslexia-a learning disability that affects reading acquisition despite normal intelligence and adequate education-have a poor rhythmic perception. It has been suggested that an accurate perception of rhythmical/metrical structure, that requires accurate perception of rise time, may be critical for phonological development and subsequent literacy. This hypothesis is mostly based on results showing a high degree of correlation between phonological awareness and metrical skills, using a very specific metrical task. We present new findings from the analysis of a sample of 48 children with a diagnosis of dyslexia, without comorbidities. These children were assessed with neuropsychological tests, as well as specifically-devised psychoacoustic and musical tasks mostly testing temporal abilities. Associations were tested by multivariate analyses including data mining strategies, correlations and most importantly logistic regressions to understand to what extent the different auditory and musical skills can be a robust predictor of reading and phonological skills. Results show a strong link between several temporal skills and phonological and reading abilities. These findings are discussed in the framework of the neuroscience literature comparing music and language processing, with a particular interest in the links between rhythm processing in music and language.

  7. An allele of the crm gene blocks cyanobacterial circadian rhythms.

    Science.gov (United States)

    Boyd, Joseph S; Bordowitz, Juliana R; Bree, Anna C; Golden, Susan S

    2013-08-20

    The SasA-RpaA two-component system constitutes a key output pathway of the cyanobacterial Kai circadian oscillator. To date, rhythm of phycobilisome associated (rpaA) is the only gene other than kaiA, kaiB, and kaiC, which encode the oscillator itself, whose mutation causes completely arrhythmic gene expression. Here we report a unique transposon insertion allele in a small ORF located immediately upstream of rpaA in Synechococcus elongatus PCC 7942 termed crm (for circadian rhythmicity modulator), which results in arrhythmic promoter activity but does not affect steady-state levels of RpaA. The crm ORF complements the defect when expressed in trans, but only if it can be translated, suggesting that crm encodes a small protein. The crm1 insertion allele phenotypes are distinct from those of an rpaA null; crm1 mutants are able to grow in a light:dark cycle and have no detectable oscillations of KaiC phosphorylation, whereas low-amplitude KaiC phosphorylation rhythms persist in the absence of RpaA. Levels of phosphorylated RpaA in vivo measured over time are significantly altered compared with WT in the crm1 mutant as well as in the absence of KaiC. Taken together, these results are consistent with the hypothesis that the Crm polypeptide modulates a circadian-specific activity of RpaA.

  8. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    Science.gov (United States)

    Bonmati-Carrion, Maria Angeles; Arguelles-Prieto, Raquel; Martinez-Madrid, Maria Jose; Reiter, Russel; Hardeland, Ruediger; Rol, Maria Angeles; Madrid, Juan Antonio

    2014-01-01

    Currently, in developed countries, nights are excessively illuminated (light at night), whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD), including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs) and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system. PMID:25526564

  9. Rhythm perception and production predict reading abilities in developmental dyslexia

    Directory of Open Access Journals (Sweden)

    Elena eFlaugnacco

    2014-06-01

    Full Text Available Rhythm organizes events in time and plays a major role in music, but also in the phonology and prosody of a language. Interestingly, children with developmental dyslexia - a learning disability that affects reading acquisition despite normal intelligence and adequate education - have a poor rhythmic perception. It has been suggested that an accurate perception of rhythmical/metrical structure, that requires accurate perception of rise time, may be critical for phonological development and subsequent literacy. This hypothesis is mostly based on results showing a high degree of correlation between phonological awareness and metrical skills, using a very specific metrical task. We present new findings from the analysis of a sample of 48 children with a diagnosis of dyslexia, without comorbidities. These children were assessed with neuropsychological tests, as well as specifically-devised psychoacoustic and musical tasks mostly testing temporal abilities. Associations were tested by multivariate analyses including data mining strategies, correlations and most importantly logistic regressions to understand to what extent the different auditory and musical skills can be a robust predictor of reading and phonological skills. Results show a strong link between several temporal skills and phonological and reading abilities. These findings are discussed in the framework of the neuroscience literature comparing music and language processing, with a particular interest in the links between rhythm processing in music and language.

  10. Circadian rhythms, nutrition and implications for longevity in urban environments.

    Science.gov (United States)

    Froy, O

    2017-10-25

    Presently, about 12% of the population is 65 years or older and by the year 2030 that figure is expected to reach 21%. In order to promote the well-being of the elderly and to reduce the costs associated with health care demands, increased longevity should be accompanied by ageing attenuation. Energy restriction, which limits the amount of energy consumed to 60-70% of the daily intake, and intermittent fasting, which allows the food to be available ad libitum every other day, extend the life span of mammals and prevent or delay the onset of major age-related diseases, such as cancer, diabetes and cataracts. Recently, we have shown that well-being can be achieved by resetting of the circadian clock and induction of robust catabolic circadian rhythms via timed feeding. In addition, the clock mechanism regulates metabolism and major metabolic proteins are key factors in the core clock mechanism. Therefore, it is necessary to increase our understanding of circadian regulation over metabolism and longevity and to design new therapies based on this regulation. This review will explore the present data in the field of circadian rhythms, ageing and metabolism.

  11. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    Directory of Open Access Journals (Sweden)

    Maria Angeles Bonmati-Carrion

    2014-12-01

    Full Text Available Currently, in developed countries, nights are excessively illuminated (light at night, whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD, including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system.

  12. Basic Principles of Interpersonal Social Rhythm Therapy in Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Gokben Hizli Sayar

    2014-08-01

    Full Text Available Interpersonal Social Rhythm Therapy is a psychotherapy modality that helps the patient recognize the relationship between disruptions in social rhythms and the onset of previous episodes of psychiatric disorders. It uses psychoeducation and behavioral techniques to maintain social rhythm and sleep/wake regularity. It is closely related to and ldquo;social zeitgeber theory and rdquo; that emphasizes the importance that social rhythm regularity may play in synchronization of circadian rhythms in individuals with or at risk for bipolar spectrum disorders. Interpersonal and social rhythm therapy have been shown to stabilize social rhythms and enhance course and outcome in bipolar disorder. This review focuses on the theoretical principles and the basic steps of interpersonal and social rhythm therapy as a psychotherapy approach in bipolar disorder. PubMed, Scopus, Google Scholar databases were searched without temporal restriction. Search terms included interpersonal social rhythm therapy, bipolar, mood disorders. Abstracts were reviewed for relevance, and randomized controlled trials of interpersonal and social rhythm therapy in bipolar disorder selected. These researches also summarized on the final part of this review. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 438-446

  13. Rate Control versus Rhythm Control for Atrial Fibrillation after Cardiac Surgery.

    Science.gov (United States)

    Gillinov, A Marc; Bagiella, Emilia; Moskowitz, Alan J; Raiten, Jesse M; Groh, Mark A; Bowdish, Michael E; Ailawadi, Gorav; Kirkwood, Katherine A; Perrault, Louis P; Parides, Michael K; Smith, Robert L; Kern, John A; Dussault, Gladys; Hackmann, Amy E; Jeffries, Neal O; Miller, Marissa A; Taddei-Peters, Wendy C; Rose, Eric A; Weisel, Richard D; Williams, Deborah L; Mangusan, Ralph F; Argenziano, Michael; Moquete, Ellen G; O'Sullivan, Karen L; Pellerin, Michel; Shah, Kinjal J; Gammie, James S; Mayer, Mary Lou; Voisine, Pierre; Gelijns, Annetine C; O'Gara, Patrick T; Mack, Michael J

    2016-05-19

    Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable condition, the best initial treatment strategy--heart-rate control or rhythm control--remains controversial. Patients with new-onset postoperative atrial fibrillation were randomly assigned to undergo either rate control or rhythm control. The primary end point was the total number of days of hospitalization within 60 days after randomization, as assessed by the Wilcoxon rank-sum test. Postoperative atrial fibrillation occurred in 695 of the 2109 patients (33.0%) who were enrolled preoperatively; of these patients, 523 underwent randomization. The total numbers of hospital days in the rate-control group and the rhythm-control group were similar (median, 5.1 days and 5.0 days, respectively; P=0.76). There were no significant between-group differences in the rates of death (P=0.64) or overall serious adverse events (24.8 per 100 patient-months in the rate-control group and 26.4 per 100 patient-months in the rhythm-control group, P=0.61), including thromboembolic and bleeding events. About 25% of the patients in each group deviated from the assigned therapy, mainly because of drug ineffectiveness (in the rate-control group) or amiodarone side effects or adverse drug reactions (in the rhythm-control group). At 60 days, 93.8% of the patients in the rate-control group and 97.9% of those in the rhythm-control group had had a stable heart rhythm without atrial fibrillation for the previous 30 days (P=0.02), and 84.2% and 86.9%, respectively, had been free from atrial fibrillation from discharge to 60 days (P=0.41). Strategies for rate control and rhythm control to treat postoperative atrial fibrillation were associated with equal numbers of days of hospitalization, similar complication rates, and similarly low rates of persistent atrial fibrillation 60 days after onset. Neither

  14. Comparison of antiarrhythmics used in patients with paroxysmal atrial fibrillation: subanalysis of J-RHYTHM Study.

    Science.gov (United States)

    Aizawa, Yoshiyasu; Kohsaka, Shun; Suzuki, Shinya; Atarashi, Hirotsugu; Kamakura, Shiro; Sakurai, Masayuki; Nakaya, Haruaki; Fukatani, Masahiko; Mitamura, Hideo; Yamazaki, Tsutomu; Yamashita, Takeshi; Ogawa, Satoshi

    2010-01-01

    The J-RHYTHM (Japanese Rhythm Management Trial for Atrial Fibrillation) study demonstrated the benefit of rhythm-control compared with rate-control in Japanese patients with paroxysmal atrial fibrillation (AF), according to AF-specific quality of life scores. However, detailed information on prescribed antiarrhythmic agents remains unclear. Data for 419 patients enrolled in the rhythm-control arm of J-RHYTHM were analyzed. The primary endpoint was defined as a composite of total mortality, cerebral infarction, embolism, bleeding, heart failure, and physical/psychological disability. The secondary endpoint was recurrence of AF. The clinical outcome according to choice of initial antiarrhythmic agent (AA) was assessed by Kaplan-Meier survival curve, and further adjusted by Cox-regression hazard model. The primary endpoint occurred in 16.9%, 6.7%, 15.8% and 23.3% of patients assigned to class Ia, Ib, Ic and III agents (P=0.359). The rate of AF recurrence was significantly higher in patients taking a class III drug (Ia, Ib, Ic, III=20.3, 23.3, 29.1, 50.0%; P=0.002). However, after adjustment for other clinical variables, the choice of AA was not associated with recurrence of AF (class I vs III, P=0.15). The incidence of each endpoint did not differ according to the choice of AA. The class III drugs seemed to lower the sinus rhythm maintenance rate, which might be confounded by other comorbid conditions. (Circ J 2010; 74: 71 - 76).

  15. Is VF an Ablatable Rhythm?

    Science.gov (United States)

    Cheniti, Ghassen; Hocini, Meleze; Martin, Ruairidh; Sacher, Frederic; Dubois, Remi; Haissaguerre, Michel; Jais, Pierre

    2017-02-01

    Ventricular fibrillation (VF) has traditionally been considered to be a disorganized arrhythmia not amenable to catheter ablation. However, a better understanding of the VF pathophysiology has allowed identification of targets for ablation. Ablation targeting the premature ventricular complexes which trigger VF was proven to be associated with high success rates and long-term freedom from VF recurrence. Recent mapping data has identified rotors, focal breakthroughs, and figure of eight re-entries as main drivers maintaining human VF. Most interestingly, the type and the spatiotemporal behavior of these drivers are reproducible between different VF episodes. In addition, drivers are usually clustered at the scar borders. This has ushered in a new era of ablation targeting the VF substrate and the drivers maintaining VF with promising results.

  16. Biologic Rhythms Derived from Siberian Mammoths Hairs

    Energy Technology Data Exchange (ETDEWEB)

    M Spilde; A Lanzirotti; C Qualls; G Phillips; A Ali; L Agenbroad; O Appenzeller

    2011-12-31

    Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was {approx}31 cms/year and {approx}16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  17. Stability and fragmentation of the activity rhythm across the sleep-wake cycle: the importance of age, lifestyle, and mental health.

    Science.gov (United States)

    Luik, Annemarie I; Zuurbier, Lisette A; Hofman, Albert; Van Someren, Eus J W; Tiemeier, Henning

    2013-12-01

    The rhythms of activity across the 24-h sleep-wake cycle, determined in part by the circadian clock, change with aging. Few large-scale studies measured the activity rhythm objectively in the general population. The present population-based study in middle-aged and elderly persons evaluated how activity rhythms change with age, and additionally investigated sociodemographics, mental health, lifestyle, and sleep characteristics as determinants of rhythms of activity. Activity rhythms were measured objectively with actigraphy. Recordings of at least 96 h (138 ± 14 h, mean ± SD) were collected from 1734 people (age: 62 ± 9.4 yrs) participating in the Rotterdam Study. Activity rhythms were quantified by calculating interdaily stability, i.e., the stability of the rhythm over days, and intradaily variability, i.e., the fragmentation of the rhythm relative to its 24-h amplitude. We assessed age, gender, presence of a partner, employment, cognitive functioning, depressive symptoms, body mass index (BMI), coffee use, alcohol use, and smoking as determinants. The results indicate that older age is associated with a more stable 24-h activity profile (β = 0.07, p = 0.02), but also with a more fragmented distribution of periods of activity and inactivity (β = 0.20, p health issues in old age.

  18. Irregular 24-hour activity rhythms and the metabolic syndrome in older adults.

    Science.gov (United States)

    Sohail, Shahmir; Yu, Lei; Bennett, David A; Buchman, Aron S; Lim, Andrew S P

    2015-01-01

    Circadian rhythms - near 24 h intrinsic biological rhythms - modulate many aspects of human physiology and hence disruption of circadian rhythms may have an important impact on human health. Experimental work supports a potential link between irregular circadian rhythms and several key risk factors for cardiovascular disease including hypertension, obesity, diabetes and dyslipidemia, collectively termed the metabolic syndrome. While several epidemiological studies have demonstrated an association between shift-work and the components of the metabolic syndrome in working-age adults, there is a relative paucity of data concerning the impact of non-occupational circadian irregularity in older women and men. To address this question, we studied 7 days of actigraphic data from 1137 older woman and men participating in the Rush Memory and Aging Project, a community-based cohort study of the chronic conditions of aging. The regularity of activity rhythms was quantified using the nonparametric interdaily stability metric, and was related to the metabolic syndrome and its components obesity, hypertension, diabetes and dyslipidemia. More regular activity rhythms were associated with a lower odds of having the metabolic syndrome (OR = 0.69, 95% CI = 0.60-0.80, p = 5.8 × 10(-7)), being obese (OR = 0.73, 95% CI = 0.63-0.85, p = 2.5 × 10(-5)), diabetic (OR = 0.76, 95% CI = 0.65-0.90, p = 9.3 × 10(-4)), hypertensive (OR = 0.78, 95% CI = 0.66-0.91, p = 2.0 × 10(-3)) or dyslipidemic (OR = 0.82, 95% CI = 0.72-0.92, p = 1.2 × 10(-3)). These associations were independent of differences in objectively measured total daily physical activity or rest, and were not accounted for by prevalent coronary artery disease, stroke or peripheral artery disease. Moreover, more regular activity rhythms were associated with lower odds of having cardiovascular disease (OR = 0.83; 95% CI = 0.73-0.95, p = 5

  19. The effect of paired pitch, rhythm, and speech on working memory as measured by sequential digit recall.

    Science.gov (United States)

    Silverman, Michael J

    2007-01-01

    Educational and therapeutic objectives are often paired with music to facilitate the recall of information. The purpose of this study was to isolate and determine the effect of paired pitch, rhythm, and speech on undergraduate's memory as measured by sequential digit recall performance. Participants (N = 120) listened to 4 completely counterbalanced treatment conditions each consisting of 9 randomized monosyllabic digits paired with speech, pitch, rhythm, and the combination of pitch and rhythm. No statistically significant learning or order effects were found across the 4 trials. A 3-way repeated-measures ANOVA indicated a statistically significant difference in digit recall performance across treatment conditions, positions, groups, and treatment by position. No other comparisons resulted in statistically significant differences. Participants were able to recall digits from the rhythm condition most accurately while recalling digits from the speech and pitch only conditions the least accurately. Consistent with previous research, the music major participants scored significantly higher than non-music major participants and the main effect associated with serial position indicated that recall performance was best during primacy and recency positions. Analyses indicated an interaction between serial position and treatment condition, also a result consistent with previous research. The results of this study suggest that pairing information with rhythm can facilitate recall but pairing information with pitch or the combination of pitch and rhythm may not enhance recall more than speech when participants listen to an unfamiliar musical selection only once. Implications for practice in therapy and education are made as well as suggestions for future research.

  20. Nonlinear neurodynamics in representation of a rhythm of speech.

    Science.gov (United States)

    Skljarov, O P

    1999-06-01

    The mathematical model is offered to describe an algorithm for functioning of a speech rhythm. The duration of a speech signal is divided into the numbered sequence of durations of voice and voiceless segments. All elements of this sequence will be considered as values normalized on the maximum element. We determine this sequence of the elements as a speech rhythm. 1) The model describes a speech rhythm as the recurrent relations between elements of a rhythm. 2) The model permits use of the concept of information entropy. 3) The model explains experimental findings obtained by our research group during comparative investigation of a rhythm in normal speech and stuttering. In particular, the model explains the existence of two classes of stutterers with various rhythms of speech.

  1. The influence of biological rhythms on host-parasite interactions.

    Science.gov (United States)

    Martinez-Bakker, Micaela; Helm, Barbara

    2015-06-01

    Biological rhythms, from circadian control of cellular processes to annual cycles in life history, are a main structural element of biology. Biological rhythms are considered adaptive because they enable organisms to partition activities to cope with, and take advantage of, predictable fluctuations in environmental conditions. A flourishing area of immunology is uncovering rhythms in the immune system of animals, including humans. Given the temporal structure of immunity, and rhythms in parasite activity and disease incidence, we propose that the intersection of chronobiology, disease ecology, and evolutionary biology holds the key to understanding host-parasite interactions. Here, we review host-parasite interactions while explicitly considering biological rhythms, and propose that rhythms: influence within-host infection dynamics and transmission between hosts, might account for diel and annual periodicity in host-parasite systems, and can lead to a host-parasite arms race in the temporal domain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Pitx2 modulates a Tbx5-dependent gene regulatory network to maintain atrial rhythm.

    Science.gov (United States)

    Nadadur, Rangarajan D; Broman, Michael T; Boukens, Bastiaan; Mazurek, Stefan R; Yang, Xinan; van den Boogaard, Malou; Bekeny, Jenna; Gadek, Margaret; Ward, Tarsha; Zhang, Min; Qiao, Yun; Martin, James F; Seidman, Christine E; Seidman, Jon; Christoffels, Vincent; Efimov, Igor R; McNally, Elizabeth M; Weber, Christopher R; Moskowitz, Ivan P

    2016-08-31

    Cardiac rhythm is extremely robust, generating 2 billion contraction cycles during the average human life span. Transcriptional control of cardiac rhythm is poorly understood. We found that removal of the transcription factor gene Tbx5 from the adult mouse caused primary spontaneous and sustained atrial fibrillation (AF). Atrial cardiomyocytes from the Tbx5-mutant mice exhibited action potential abnormalities, including spontaneous depolarizations, which were rescued by chelating free calcium. We identified a multitiered transcriptional network that linked seven previously defined AF risk loci: TBX5 directly activated PITX2, and TBX5 and PITX2 antagonistically regulated membrane effector genes Scn5a, Gja1, Ryr2, Dsp, and Atp2a2 In addition, reduced Tbx5 dose by adult-specific haploinsufficiency caused decreased target gene expression, myocardial automaticity, and AF inducibility, which were all rescued by Pitx2 haploinsufficiency in mice. These results defined a transcriptional architecture for atrial rhythm control organized as an incoherent feed-forward loop, driven by TBX5 and modulated by PITX2. TBX5/PITX2 interplay provides tight control of atrial rhythm effector gene expression, and perturbation of the co-regulated network caused AF susceptibility. This work provides a model for the molecular mechanisms underpinning the genetic implication of multiple AF genome-wide association studies loci and will contribute to future efforts to stratify patients for AF risk by genotype. Copyright © 2016, American Association for the Advancement of Science.

  3. Daily rhythm of salivary IL-1ß, cortisol and melatonin in day and night workers.

    Science.gov (United States)

    Reinhardt, Érica Lui; Fernandes, Pedro Augusto Carlos Magno; Markus, Regina Pekelmann; Fischer, Frida Marina

    2012-01-01

    Shiftwork-induced sleep deprivation and circadian disruption probably leads to an increase in the production of cytokines and dysregulation of innate immune system, respectively. This project aims evaluating changes in salivary IL-1 beta, cortisol, and melatonin in night workers. Method. Two day and three night healthy workers participated in this study. Sleep was evaluated by actimetry and activity protocols. Saliva was collected at waking and bedtime the last workday and the following two days-off and was analyzed by ELISA. Results. Neither sleep duration nor efficiency showed any association with salivary IL-1beta. IL-1beta levels were higher at waking than at bedtime during working days for all workers, but only one day and one night-worker maintained this pattern and hormone rhythms during days off. For this night worker, melatonin levels were shifted to daytime. A second one presented clear alterations in IL-1beta and hormone rhythms on days-off. Conclusions. Our preliminary results suggest that night work can disturb the variation pattern of salivary IL-1beta. No association of this variation with sleep was observed. It seems that disruption in hormone rhythms interfere with salivary IL-1beta production. IL- 1beta production pattern seems to be maintained when rhythms are present, in spite of a shift in melatonin secretion.

  4. Pecking and respiration rhythms of pigeons (Columba livia)

    OpenAIRE

    Hörster, Wolfgang; Xia, Li; Delius, Juan

    2003-01-01

    The production and coordination of rhythmic activities in birds is seldom investigated. Here we describe the pecking and breathing rhythms of pigeons under different conditions. When feeding from a heap of small grains, hungry pigeons pecked at regular intervals of about 0.3 s. The pecking rhythm was slightly slower in the afternoon. The pecking rhythm induced by the dopaminergic drug apomorphine was somewhat faster but some overt pecks were skipped. The mean respiratory cycle during a nonpec...

  5. Tapped out: do people with aphasia have rhythm processing deficits?

    Science.gov (United States)

    Zipse, Lauryn; Worek, Amanda; Guarino, Anthony J; Shattuck-Hufnagel, Stefanie

    2014-12-01

    In this study, the authors tested whether people with aphasia (PWAs) show an impaired ability to process rhythm, both in terms of perception and production. Two experiments were conducted. In Experiment 1, 16 PWAs and 15 age-matched control participants performed 3 rhythm tasks: tapping along to short rhythms, tapping these same rhythms from memory immediately after presentation, and making same-different judgments about pairs of tapped rhythms that they heard. Comparison tasks measured same-different judgment ability with visual stimuli and nonverbal working memory (Corsi blocks). In Experiment 2, 14 PWAs and 16 control participants made same-different judgments for pairs of auditory stimuli that differed in terms of rhythm or pitch (for comparison). In Experiment 1, PWAs performed worse than control participants across most measures of rhythm processing. In contrast, PWAs and control participants did not differ in their performance on the comparison tasks. In Experiment 2, the PWAs performed worse than control participants across all conditions but with a more marked deficit in stimulus pairs that differed in rhythm than in those that differed in pitch. The results support the hypothesis that at least some PWAs exhibit deficits of rhythm and timing. This may have implications for treatments involving tapping or other rhythmic cues.

  6. How does the brain create rhythms?

    Science.gov (United States)

    Szirmai, Imre

    2010-01-30

    Connection was found between rhythmic cortical activity and motor control. The 10 Hz micro-rhythm and the 20-30 Hz bursts represent two functional states of the somatomotor system. A correspondence of the central micro-rhythm of the motor cortex and the physiological hand tremor (8-12 Hz) is presumed. The precise tuning of the motor system can be estimated by the frequency of repetitive finger movements. In complex tapping exercise, the index finger is the most skillful, the 3rd, 4th and 5th fingers keep rhythm with less precision. It was found that the organization of mirror movements depends on the cortical representation of fingers. Mirror finger movements are more regular if the subject begins the motor action with the 5th (small) finger. Concerning cortical regulation of finger movements, it was suggested that there are two time-keeping systems in the brain; one with a sensitivity above and another with a sensitivity below the critical frequency of 3 Hz. The preferred meter which helps to maintain synchronous finger movements is the cadence of 4/4 and 8/8. We observed that the unlearned inward-outward sequential finger movement was equally impaired in nonmusician controls and patients with Parkinson-disease. In movement disorders, the ability of movement and the "clock-mechanism" are equally involved. The polyrhythmic finger movement is not our inborn ability, it has to be learned. The "timer" function, which regulates the rhythmic movement, is presumably localised in the basal ganglia or in the cerebellum. The meter of the music is built on the reciprocal values of 2 raised to the second to fifth power (1/1(2), 1/2(2), 1/2(3), 1/2(4), 1/2(5)). The EEG frequencies that we consider important in the regulation of conscious motor actions are approximately in the same domain (4, 8, 16, 32, 64 Hz). During music performance, an important neural process is the coupling of distant brain areas. Concerning melody, the musical taste of Europeans is octave-based. Musical

  7. Musical rhythms in heart period dynamics: a cross-cultural and interdisciplinary approach to cardiac rhythms.

    Science.gov (United States)

    Bettermann, H; Amponsah, D; Cysarz, D; van Leeuwen, P

    1999-11-01

    The purpose of this study was to expand classic heart period analysis methods by techniques from ethnomusicology that explicitly take complex musical rhythm principles into consideration. The methods used are based on the theory of African music, the theory of symbolic dynamics, and combinatorial theory. Heart period tachograms from 192 24-h electrocardiograms of 96 healthy subjects were transformed into binary symbol sequences that were interpretable as elementary rhythmic (percussive) patterns, the time lines in African music. Using a hierarchical rhythm pattern scheme closely related to the Derler Rhythm Classification (from jazz theory), we calculated the predominance and stability of pattern classes. The results show that during sleep certain classes, specific to individuals, occurred in a cyclically recurrent manner and many times more often than expected. Simultaneously, other classes disappeared more or less completely. Moreover, the most frequent classes obviously originate from phase-locking processes in autonomic regulation (e.g., between respiratory and cardiac cycles). In conclusion, the new interdisciplinary method presented here demonstrates that heart period patterns, in particular those occurring during night sleep, can be interpreted as musical rhythms. This method may be of great potential use in music therapy research.

  8. SLEEP AND CIRCADIAN RHYTHM DISORDERS IN PARKINSON'S DISEASE.

    Science.gov (United States)

    Gros, Priti; Videnovic, Aleksandar

    2017-09-01

    Sleep disorders are among the most challenging non-motor features of Parkinson's disease (PD) and significantly affect quality of life. Research in this field has gained recent interest among clinicians and scientists and is rapidly evolving. This review is dedicated to sleep and circadian dysfunction associated with PD. Most primary sleep disorders may co-exist with PD; majority of these disorders have unique features when expressed in the PD population. We discuss the specific considerations related to the common sleep problems in Parkinson's disease including insomnia, rapid eye movement sleep behavior disorder, restless legs syndrome, sleep disordered breathing, excessive daytime sleepiness and circadian rhythm disorders. Within each of these sleep disorders, we present updated definitions, epidemiology, etiology, diagnosis, clinical implications and management. Furthermore, areas of potential interest for further research are outlined.

  9. Sleep and circadian rhythm disruption in psychiatric and neurodegenerative disease.

    Science.gov (United States)

    Wulff, Katharina; Gatti, Silvia; Wettstein, Joseph G; Foster, Russell G

    2010-08-01

    Sleep and circadian rhythm disruption are frequently observed in patients with psychiatric disorders and neurodegenerative disease. The abnormal sleep that is experienced by these patients is largely assumed to be the product of medication or some other influence that is not well defined. However, normal brain function and the generation of sleep are linked by common neurotransmitter systems and regulatory pathways. Disruption of sleep alters sleep-wake timing, destabilizes physiology and promotes a range of pathologies (from cognitive to metabolic defects) that are rarely considered to be associated with abnormal sleep. We propose that brain disorders and abnormal sleep have a common mechanistic origin and that many co-morbid pathologies that are found in brain disease arise from a destabilization of sleep mechanisms. The stabilization of sleep may be a means by which to reduce the symptoms of--and permit early intervention of--psychiatric and neurodegenerative disease.

  10. The suprachiasmatic nucleus: age-related decline in biological rhythms.

    Science.gov (United States)

    Nakamura, Takahiro J; Takasu, Nana N; Nakamura, Wataru

    2016-09-01

    Aging is associated with changes in sleep duration and quality, as well as increased rates of pathologic/disordered sleep. While several factors contribute to these changes, emerging research suggests that age-related changes in the mammalian central circadian clock within the suprachiasmatic nucleus (SCN) may be a key factor. Prior work from our group suggests that circadian output from the SCN declines because of aging. Furthermore, we have previously observed age-related infertility in female mice, caused by a mismatch between environmental light-dark cycles and the intrinsic, internal biological clocks. In this review, we address regulatory mechanisms underlying circadian rhythms in mammals and summarize recent literature describing the effects of aging on the circadian system.

  11. Frailty syndrome

    DEFF Research Database (Denmark)

    Fumagalli, Stefano; Potpara, Tatjana S; Bjerregaard Larsen, Torben

    2017-01-01

    The age of patients presenting with complex arrhythmias is increasing. Frailty is a multifaceted syndrome characterized by an increased vulnerability to stressors and a decreased ability to maintain homeostasis. The prevalence of frailty is associated with age. The aims of this European Heart...... Rhythm Association (EHRA) EP Wire survey were to evaluate the proportion of patients with frailty and its influence on the clinical management of arrhythmias. A total of 41 centres-members of the EHRA Electrophysiology Research Network-in 14 European countries completed the web-based questionnaire...... in June 2017. Patients over 70 years represented 53% of the total treated population, with the proportion of frail elderly individuals reaching approximately 10%; 91.7% of the responding centres reported treating frail subjects in the previous year. The respondents usually recognized frailty based...

  12. Circadian rhythm disruption as a link between Attention-Deficit/Hyperactivity Disorder and obesity?

    Science.gov (United States)

    Vogel, Suzan W N; Bijlenga, Denise; Tanke, Marjolein; Bron, Tannetje I; van der Heijden, Kristiaan B; Swaab, Hanna; Beekman, Aartjan T F; Kooij, J J Sandra

    2015-11-01

    Patients with Attention-Deficit/Hyperactivity Disorder (ADHD) have a high prevalence of obesity. This is the first study to investigate whether circadian rhythm disruption is a mechanism linking ADHD symptoms to obesity. ADHD symptoms and two manifestations of circadian rhythm disruption: sleep problems and an unstable eating pattern (skipping breakfast and binge eating later in the day) were assessed in participants with obesity (n= 114), controls (n= 154), and adult ADHD patients (n= 202). Participants with obesity had a higher prevalence of ADHD symptoms and short sleep on free days as compared to controls, but a lower prevalence of ADHD symptoms, short sleep on free days, and an unstable eating pattern as compared to ADHD patients.We found that participants with obesity had a similar prevalence rate of an unstable eating pattern when compared to controls. Moreover, mediation analyses showed that both sleep duration and an unstable eating pattern mediated the association between ADHD symptoms and body mass index (BMI). Our study supports the hypothesis that circadian rhythm disruption is a mechanism linking ADHD symptoms to obesity. Further research is needed to determine if treatment of ADHD and circadian rhythm disruption is effective in the prevention and treatment of obesity in patients with obesity and/or ADHD. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Effect of Sudarshan Kriya (meditation) on gamma, alpha, and theta rhythm during working memory task.

    Science.gov (United States)

    Chandra, Sushil; Sharma, Greeshma; Mittal, Alok Prakash; Jha, Devendra

    2016-01-01

    The present study focuses on analyzing the effects of Sudarshan Kriya yoga (SKY) on brain signals during a working memory (WM) task. To envision the significant effects of SKY on WM capacity (WMC), we chose a control group for contriving a cogent comparison that could be corroborated using statistical tests. A total of 25 subjects were taken in the study, of which 10 were allotted to a control group and 15 to an experimental group. Electroencephalograph was taken during a WM task, which was an automated operation span test before and after SKY with 90 days intervals. No SKY was given to the control group. t-test and one-way ANOVA were applied. SKY promoted the efficient use of energy and power spectral density (PSD) for different brain rhythms in the desired locations as depicted by the gamma (F8 channel), alpha, and theta 2 (F7 and FC5) bands. It was found that gamma PSD reduced for both phases of memory in the experimental group. Alpha energy increased during the retrieval phase in the experimental group after SKY. Theta 1 rhythm was not affected by SKY, but theta 2 had shown left hemispheric activation. Theta rhythm was associated with memory consolidation. SKY had shown minimized energy losses while performing the task. SKY can improve WMC by changing the brain rhythms such that energy is utilized efficiently in performing the task.

  14. Atrial fibrillation: what have recent trials taught us regarding pharmacologic management of rate and rhythm control?

    Science.gov (United States)

    Reiffel, James A

    2011-02-01

    The management of atrial fibrillation (AF) focuses on control of heart rate, correction of rhythm disturbance, prophylaxis of thromboembolism, treatment of underlying disorders, and pathophysiologic mechanisms, and more recently on costs, hospitalizations, and other AF consequences. The goals of therapy are to reduce morbidity and mortality and improve quality of life (QOL). Several large studies have examined the relative efficacy of rhythm- versus rate-control strategies with respect to these outcomes, and have largely failed to demonstrate a survival advantage with either approach by intention-to-treat analysis--both in patients with and without heart failure (HF). However, the results do not support the hypothesis that rate control is preferable as first-line therapy for AF with respect to survival and do not disprove the hypothesis that maintenance of sinus rhythm is preferable to the continuation of AF, particularly if rate control fails to restore adequate QOL or if selective approaches are employed. Many post hoc analyses and substudies have assessed QOL, functional status, and exercise tolerance, with the majority demonstrating important benefits associated with achievement of rhythm control. Moreover, some subanalyses and additional trials have suggested that sinus rhythm can be associated with longer survival, including in patients with HF. In addition, ATHENA demonstrated that a drug, dronedarone, could improve the composite endpoint of cardiovascular hospitalizations and all-cause mortality in a carefully selected, high-risk, nonpermanent AF population, in addition to its recognized reduction in AF. This review examines the clinical outcomes of several important AF trials, discusses the limitations in applying the major morbidity/mortality findings to everyday clinical practice, and summarizes the lessons learned. ©2010, The Author. Journal compilation ©2010 Wiley Periodicals, Inc.

  15. Dim light at night disrupts molecular circadian rhythms and increases body weight.

    Science.gov (United States)

    Fonken, Laura K; Aubrecht, Taryn G; Meléndez-Fernández, O Hecmarie; Weil, Zachary M; Nelson, Randy J

    2013-08-01

    With the exception of high latitudes, life has evolved under bright days and dark nights. Most organisms have developed endogenously driven circadian rhythms that are synchronized to this daily light/dark cycle. In recent years, humans have shifted away from the naturally occurring solar light cycle in favor of artificial and sometimes irregular light schedules produced by electric lighting. Exposure to unnatural light cycles is increasingly associated with obesity and metabolic syndrome; however, the means by which environmental lighting alters metabolism are poorly understood. Thus, we exposed mice to dim light at night and investigated changes in the circadian system and metabolism. Here we report that exposure to ecologically relevant levels of dim (5 lux) light at night altered core circadian clock rhythms in the hypothalamus at both the gene and protein level. Circadian rhythms in clock expression persisted during light at night; however, the amplitude of Per1 and Per2 rhythms was attenuated in the hypothalamus. Circadian oscillations were also altered in peripheral tissues critical for metabolic regulation. Exposure to dimly illuminated, as compared to dark, nights decreased the rhythmic expression in all but one of the core circadian clock genes assessed in the liver. Additionally, mice exposed to dim light at night attenuated Rev-Erb expression in the liver and adipose tissue. Changes in the circadian clock were associated with temporal alterations in feeding behavior and increased weight gain. These results are significant because they provide evidence that mild changes in environmental lighting can alter circadian and metabolic function. Detailed analysis of temporal changes induced by nighttime light exposure may provide insight into the onset and progression of obesity and metabolic syndrome, as well as other disorders involving sleep and circadian rhythm disruption.

  16. Rhythms For Cognition: Communication Through Coherence

    Science.gov (United States)

    Fries, Pascal

    2015-01-01

    I propose that synchronization affects communication between neuronal groups. Gamma-band (30-90 Hz) synchronization modulates excitation rapidly enough so it escapes the following inhibition and activates postsynaptic neurons effectively. Synchronization also ensures that a presynaptic activation pattern arrives at postsynaptic neurons in a temporally coordinated manner. At a postsynaptic neuron, multiple presynaptic groups converge, e.g. representing different stimuli. If a stimulus is selected by attention, its neuronal representation shows stronger and higher-frequency gamma-band synchronization. Thereby, the attended stimulus representation selectively entrains postsynaptic neurons. The entrainment creates sequences of short excitation and longer inhibition that are coordinated between pre- and postsynaptic groups to transmit the attended representation and shut out competing inputs. The predominantly bottom-up directed gamma-band influences are controlled by predominantly top-down directed alpha-beta band (8-20 Hz) influences. Attention itself samples stimuli at a 7-8 Hz theta rhythm. Thus, several rhythms and their interplay render neuronal communication effective, precise and selective. PMID:26447583

  17. Circadian rhythm and its role in malignancy

    Directory of Open Access Journals (Sweden)

    Mahmood Saqib

    2010-03-01

    Full Text Available Abstract Circadian rhythms are daily oscillations of multiple biological processes directed by endogenous clocks. The circadian timing system comprises peripheral oscillators located in most tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN of the hypothalamus. Circadian genes and the proteins produced by these genes constitute the molecular components of the circadian oscillator which form positive/negative feedback loops and generate circadian rhythms. The circadian regulation extends beyond clock genes to involve various clock-controlled genes (CCGs including various cell cycle genes. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle and on the ability of cells to undergo apoptosis. This may lead to genomic instability and accelerated cellular proliferation potentially promoting carcinogenesis. Different lines of evidence in mice and humans suggest that cancer may be a circadian-related disorder. The genetic or functional disruption of the molecular circadian clock has been found in various cancers including breast, ovarian, endometrial, prostate and hematological cancers. The acquisition of current data in circadian clock mechanism may help chronotherapy, which takes into consideration the biological time to improve treatments by devising new therapeutic approaches for treating circadian-related disorders, especially cancer.

  18. Circadian Rhythms, Sleep Deprivation, and Human Performance

    Science.gov (United States)

    Goel, Namni; Basner, Mathias; Rao, Hengyi; Dinges, David F.

    2014-01-01

    Much of the current science on, and mathematical modeling of, dynamic changes in human performance within and between days is dominated by the two-process model of sleep–wake regulation, which posits a neurobiological drive for sleep that varies homeostatically (increasing as a saturating exponential during wakefulness and decreasing in a like manner during sleep), and a circadian process that neurobiologically modulates both the homeostatic drive for sleep and waking alertness and performance. Endogenous circadian rhythms in neurobehavioral functions, including physiological alertness and cognitive performance, have been demonstrated using special laboratory protocols that reveal the interaction of the biological clock with the sleep homeostatic drive. Individual differences in circadian rhythms and genetic and other components underlying such differences also influence waking neurobehavioral functions. Both acute total sleep deprivation and chronic sleep restriction increase homeostatic sleep drive and degrade waking neurobehavioral functions as reflected in sleepiness, attention, cognitive speed, and memory. Recent evidence indicating a high degree of stability in neurobehavioral responses to sleep loss suggests that these trait-like individual differences are phenotypic and likely involve genetic components, including circadian genes. Recent experiments have revealed both sleep homeostatic and circadian effects on brain metabolism and neural activation. Investigation of the neural and genetic mechanisms underlying the dynamically complex interaction between sleep homeostasis and circadian systems is beginning. A key goal of this work is to identify biomarkers that accurately predict human performance in situations in which the circadian and sleep homeostatic systems are perturbed. PMID:23899598

  19. Strength of gamma rhythm depends on normalization.

    Directory of Open Access Journals (Sweden)

    Supratim Ray

    Full Text Available Neuronal assemblies often exhibit stimulus-induced rhythmic activity in the gamma range (30-80 Hz, whose magnitude depends on the attentional load. This has led to the suggestion that gamma rhythms form dynamic communication channels across cortical areas processing the features of behaviorally relevant stimuli. Recently, attention has been linked to a normalization mechanism, in which the response of a neuron is suppressed (normalized by the overall activity of a large pool of neighboring neurons. In this model, attention increases the excitatory drive received by the neuron, which in turn also increases the strength of normalization, thereby changing the balance of excitation and inhibition. Recent studies have shown that gamma power also depends on such excitatory-inhibitory interactions. Could modulation in gamma power during an attention task be a reflection of the changes in the underlying excitation-inhibition interactions? By manipulating the normalization strength independent of attentional load in macaque monkeys, we show that gamma power increases with increasing normalization, even when the attentional load is fixed. Further, manipulations of attention that increase normalization increase gamma power, even when they decrease the firing rate. Thus, gamma rhythms could be a reflection of changes in the relative strengths of excitation and normalization rather than playing a functional role in communication or control.

  20. Thoracic surface temperature rhythms as circadian biomarkers for cancer chronotherapy

    Science.gov (United States)

    Roche, Véronique Pasquale; Mohamad-Djafari, Ali; Innominato, Pasquale Fabio; Karaboué, Abdoulaye; Gorbach, Alexander; Lévi, Francis Albert

    2014-01-01

    The disruption of the temperature circadian rhythm has been associated with cancer progression, while its amplification resulted in cancer inhibition in experimental tumor models. The current study investigated the relevance of skin surface temperature rhythms as biomarkers of the Circadian Timing System (CTS) in order to optimize chronotherapy timing in individual cancer patients. Baseline skin surface temperature at four sites and wrist accelerations were measured every minute for 4 days in 16 patients with metastatic gastro-intestinal cancer before chronotherapy administration. Temperature and rest-activity were recorded, respectively, with wireless skin surface temperature patches (Respironics, Phillips) and an actigraph (Ambulatory Monitoring). Both variables were further monitored in 10 of these patients during and after a 4-day course of a fixed chronotherapy protocol. Collected at baseline, during and after therapy longitudinal data sets were processed using Fast Fourier Transform Cosinor and Linear Discriminant Analyses methods. A circadian rhythm was statistically validated with a period of 24 h (p|0.7|; p<0.05). Individual circadian acrophases at baseline were scattered from 15:18 to 6:05 for skin surface temperature, and from 12:19 to 15:18 for rest-activity, with respective median values of 01:10 (25–75% quartiles, 22:35–3:07) and 14:12 (13:14–14:31). The circadian patterns in skin surface temperature and rest-activity persisted or were amplified during and after fixed chronotherapy delivery for 5/10 patients. In contrast, transient or sustained disruption of these biomarkers was found for the five other patients, as indicated by the lack of any statistically significant dominant period in the circadian range. No consistent correlation (r<|0.7|, p ≥ 0.05) was found between paired rest-activity and temperature time series during fixed chronotherapy delivery. In conclusion, large inter-patient differences in circadian amplitudes and acrophases of

  1. Thoracic surface temperature rhythms as circadian biomarkers for cancer chronotherapy.

    Science.gov (United States)

    Roche, Véronique Pasquale; Mohamad-Djafari, Ali; Innominato, Pasquale Fabio; Karaboué, Abdoulaye; Gorbach, Alexander; Lévi, Francis Albert

    2014-04-01

    The disruption of the temperature circadian rhythm has been associated with cancer progression, while its amplification resulted in cancer inhibition in experimental tumor models. The current study investigated the relevance of skin surface temperature rhythms as biomarkers of the Circadian Timing System (CTS) in order to optimize chronotherapy timing in individual cancer patients. Baseline skin surface temperature at four sites and wrist accelerations were measured every minute for 4 days in 16 patients with metastatic gastro-intestinal cancer before chronotherapy administration. Temperature and rest-activity were recorded, respectively, with wireless skin surface temperature patches (Respironics, Phillips) and an actigraph (Ambulatory Monitoring). Both variables were further monitored in 10 of these patients during and after a 4-day course of a fixed chronotherapy protocol. Collected at baseline, during and after therapy longitudinal data sets were processed using Fast Fourier Transform Cosinor and Linear Discriminant Analyses methods. A circadian rhythm was statistically validated with a period of 24 h (p surface temperature (median, 0.72 °C), and from 16.6 to 146.1 acc/min for rest-activity (median, 88.9 acc/min). Thirty-nine pairs of baseline temperature and rest-activity time series (75%) were correlated (r > |0.7|; p surface temperature, and from 12:19 to 15:18 for rest-activity, with respective median values of 01:10 (25-75% quartiles, 22:35-3:07) and 14:12 (13:14-14:31). The circadian patterns in skin surface temperature and rest-activity persisted or were amplified during and after fixed chronotherapy delivery for 5/10 patients. In contrast, transient or sustained disruption of these biomarkers was found for the five other patients, as indicated by the lack of any statistically significant dominant period in the circadian range. No consistent correlation (r surface temperature were demonstrated for the first time in cancer patients, despite rather

  2. Neglect of Biological Rhythms in High School Biology Texts.

    Science.gov (United States)

    Ahlgren, Andrew; Nelson, Julie Ann

    1979-01-01

    This article developed from a survey of the five most popular biology texts which promote the theory of invariant homeostasis rather than biological rhythms. The popular fad of "birthdate biorhythms" is discussed in relation to providing education on biological rhythms and its legitimacy to the public. (SA)

  3. Functional synchronization of biological rhythms in a tritrophic system.

    Directory of Open Access Journals (Sweden)

    Sufang Zhang

    Full Text Available In a tritrophic system formed by a plant, an herbivore and a natural enemy, each component has its own biological rhythm. However, the rhythm correlations among the three levels and the underlying mechanisms in any tritrophic system are largely unknown. Here, we report that the rhythms exhibited bidirectional correlations in a model tritrophic system involving a lima bean, a pea leafminer and a parasitoid. From the bottom-up perspective, the rhythm was initiated from herbivore feeding, which triggered the rhythms of volatile emissions; then the rhythmic pattern of parasitoid activities was affected, and these rhythms were synchronized by a light switch signal. Increased volatile concentration can enhance the intensity of parasitoid locomotion and oviposition only under light. From the top-down perspective, naive and oviposition-experienced parasitoids were able to utilize the different volatile rhythm information from the damaged plant to locate host leafminers respectively. Our results indicated that the three interacting organisms in this system can achieve rhythmic functional synchronization under a natural light-dark photoperiod, but not under constant light or darkness. These findings provide new insight into the rhythm synchronization of three key players that contribute to the utilization of light and chemical signals, and our results may be used as potential approaches for manipulating natural enemies.

  4. Unexpected diversity in socially synchronized rhythms of shorebirds

    NARCIS (Netherlands)

    Bulla, Martin; Valcu, Mihai; Dokter, Adriaan M; Dondua, Alexei G; Kosztolányi, András; Helm, Barbara; Sandercock, Brett K; Casler, Bruce; Ens, Bruno J.; Spiegel, Caleb S; Hassell, Chris J; Küpper, Clemens; Minton, Clive; Burgas, Daniel; Lank, David B; Payer, David C; Loktionov, Egor Y; Nol, Erica; Kwon, Eunbi; Smith, Fletcher; Gates, H River; Vitnerová, Hana; Prüter, Hanna; Johnson, James A; St Clair, James J H; Lamarre, Jean-François; Rausch, Jennie; Reneerkens, Jeroen; Conklin, Jesse R; Burger, Joanna; Liebezeit, Joe; Bêty, Joël; Coleman, Jonathan T; Figuerola, Jordi; Hooijmeijer, Joslyn; Alves, José A; Smith, Joseph A M; Weidinger, Karel; Koivula, Kari; Gosbell, Ken; Exo, Klaus-Michael; Niles, Larry; Koloski, Laura; McKinnon, Laura; Praus, Libor; Klaassen, Marcel; Giroux, Marie-Andrée; Sládeček, Martin; Boldenow, Megan L; Goldstein, Michael I; Šálek, Miroslav; Senner, Nathan; Rönkä, Nelli; Lecomte, Nicolas; Gilg, Olivier; Vincze, Orsolya; Johnson, Oscar W; Smith, Paul A; Woodard, Paul F; Tomkovich, Pavel S; Battley, Phil F; Bentzen, Rebecca; Lanctot, Richard B; Porter, Ron; Saalfeld, Sarah T; Freeman, Scott; Brown, Stephen C; Yezerinac, Stephen; Székely, Tamás; Montalvo, Tomás; Piersma, Theunis; Loverti, Vanessa; Pakanen, Veli-Matti; Tijsen, Wim; Kempenaers, Bart

    2016-01-01

    The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities

  5. Biomarkers for circadian rhythm disruption independent of time of day

    NARCIS (Netherlands)

    K.C.G. van Dycke (Kirsten); J.L.A. Pennings (Jeroen L.A.); C.T.M. van Oostrom (Conny); L.W.M. Van Kerkhof (Linda W.M.); H. van Steeg (Harry); G.T.J. van der Horst (Gijsbertus); W. Rodenburg (Wendy)

    2015-01-01

    textabstractFrequent shift work causes disruption of the circadian rhythm and might on the long-term result in increased health risk. Current biomarkers evaluating the presence of circadian rhythm disturbance (CRD), including melatonin, cortisol and body temperature, require 24-hr ("around the

  6. hippocampal slow rhythms in ongoing behaviour and during

    African Journals Online (AJOL)

    1971-02-06

    Feb 6, 1971 ... HIPPOCAMPAL SLOW RHYTHMS IN ONGOING BEHAVIOUR AND DURING CLASSICAL. CONDITIONING*. R. C. ALBINO AND K. CAIGER, Psychology Department, University of Natal, Durban. Experiments on the relationships between hippocampal slow (or theta) rhythms and phases of approach ...

  7. Rhythm-based segmentation of Popular Chinese Music

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer

    2005-01-01

    We present a new method to segment popular music based on rhythm. By computing a shortest path based on the self-similarity matrix calculated from a model of rhythm, segmenting boundaries are found along the di- agonal of the matrix. The cost of a new segment is opti- mized by matching manual...

  8. Interactive Rhythm Learning System by Combining Tablet Computers and Robots

    Directory of Open Access Journals (Sweden)

    Chien-Hsing Chou

    2017-03-01

    Full Text Available This study proposes a percussion learning device that combines tablet computers and robots. This device comprises two systems: a rhythm teaching system, in which users can compose and practice rhythms by using a tablet computer, and a robot performance system. First, teachers compose the rhythm training contents on the tablet computer. Then, the learners practice these percussion exercises by using the tablet computer and a small drum set. The teaching system provides a new and user-friendly score editing interface for composing a rhythm exercise. It also provides a rhythm rating function to facilitate percussion training for children and improve the stability of rhythmic beating. To encourage children to practice percussion exercises, a robotic performance system is used to interact with the children; this system can perform percussion exercises for students to listen to and then help them practice the exercise. This interaction enhances children’s interest and motivation to learn and practice rhythm exercises. The results of experimental course and field trials reveal that the proposed system not only increases students’ interest and efficiency in learning but also helps them in understanding musical rhythms through interaction and composing simple rhythms.

  9. Perceptual tests of rhythmic similarity: II. Syllable rhythm

    NARCIS (Netherlands)

    Kim, J.; Davis, C.; Cutler, A.

    2008-01-01

    To segment continuous speech into its component words, listeners make use of language rhythm; because rhythm differs across languages, so do the segmentation procedures which listeners use. For each of stress-, syllable-and mora-based rhythmic structure, perceptual experiments have led to the

  10. Lateralization of Auditory rhythm length in temporal lobe lessions

    NARCIS (Netherlands)

    Alpherts, W.C.J.; Vermeulen, J.; Franken, M.L.O.; Hendriks, M.P.H.; Veelen, C.W.M. van; Rijen, P.C. van

    2002-01-01

    In the visual modality, short rhythmic stimuli ha c been proven to he better processed (sequentially) by the left hemisphere, while longer rhythms appear to he better (holistically) processed by the right hemisphere. This study was set up to see it the same holds in the auditory modality. The rhythm

  11. Diurnal cortisol rhythms, fatigue and psychosocial factors in five-year survivors of ovarian cancer.

    Science.gov (United States)

    Cuneo, Michaela G; Schrepf, Andrew; Slavich, George M; Thaker, Premal H; Goodheart, Michael; Bender, David; Cole, Steve W; Sood, Anil K; Lutgendorf, Susan K

    2017-10-01

    Fatigue is a challenge in ovarian cancer survivorship and greatly impacts quality of life. In other cancer populations, fatigue has been associated with abnormal diurnal cortisol patterns. However, little is known about biological and behavioral factors in 5+-year ovarian cancer survivors and potential mechanisms underlying persistent fatigue have not been investigated in this population. Moreover, relationships between neuroendocrine and psychosocial factors in 5+-year ovarian cancer survivors have not been studied. We addressed these issues by examining relationships between diurnal cortisol rhythms, fatigue, life stress, and social support in 30 survivors of ovarian cancer who were assessed at least 5 years (mean=6.20years) following their primary diagnosis. Flatter diurnal cortisol slopes were associated with higher levels of fatigue, suggesting a role for HPA-axis dysregulation in sustained fatigue experienced by survivors. Moreover, greater cumulative lifetime stressor exposure (p=0.023) and stressor severity (p=0.004) were associated with flatter diurnal cortisol slopes, while higher social attachment (p=0.001) was associated with steeper diurnal cortisol slopes. These findings suggest that ovarian cancer survivors with greater lifetime stress exposure or lower social attachment may be at increased risk for circadian rhythm disruption, which in turn is associated with fatigue. Future research should examine relationships of clinical stage and inflammatory cytokines to cortisol rhythms and fatigue in long-term ovarian cancer survivors, as well as investigating the clinical significance of abnormal diurnal cortisol profiles in this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. ‘Ragged Time’ in Intra-panel Comics Rhythms

    Directory of Open Access Journals (Sweden)

    Corry Shores

    2016-07-01

    Full Text Available A phenomenological method of comics analysis can be useful when we need to uncover the structural features of the comics experience itself. One fruitful application would be in the study of irregular intra-panel rhythms, where the temporalized divisions are not visibly indicated but rather are only experienced. By means of Gilles Deleuze’s notion of rhythmic repetition and his elaboration of it through Olivier Messiaen’s theory of ‘kinetic’ rhythm, we will formulate a conception of visual rhythm as being based on metrical irregularity. We further explicate this concept of irregular rhythm by drawing upon the notion of ‘ragged time’ in the early jazz musical form, ragtime. We finally test its usefulness by examining how the ‘jazzy’ rhythms of Cubist-styled panels by Art Spiegelman and Mary Fleener generate an experience of ragged time.

  13. Sleep and circadian rhythm disruption and recognition memory in schizophrenia.

    Science.gov (United States)

    Tam, Shu K E; Pritchett, David; Brown, Laurence A; Foster, Russell G; Bannerman, David M; Peirson, Stuart N

    2015-01-01

    Schizophrenia patients often show irregularities in sleep and circadian rhythms and deficits in recognition memory. Similar phenotypes are seen in schizophrenia-relevant genetic mouse models, such as synaptosomal associated protein of 25 kDa (Snap-25) point mutant mice, vasoactive intestinal peptide receptor 2 (Vipr2) knockout mice, and neuregulin 1 (Nrg1)-deficient mice. Sleep and circadian abnormalities and impaired recognition memory may be causally related in both schizophrenia patients and schizophrenia-relevant mouse models, since sleep deprivation, abnormal photic input, and the manipulation of core clock genes (cryptochrome 1/2) can all disrupt object recognition memory in rodent models. The recognition deficits observed in patients and mouse models (both schizophrenia-related and -unrelated) are discussed here in terms of the dual-process theory of recognition, which postulates that there are two recognition mechanisms-recollection versus familiarity-that can be selectively impaired by brain lesions, neuropsychiatric conditions, and putatively, sleep and circadian rhythm disruption. However, based on this view, the findings from patient studies and studies using genetic mouse models (Nrg1 deficiency) seem to be inconsistent with each other. Schizophrenia patients are impaired at recollection (and to a lesser extent, familiarity judgments), but Nrg1-deficient mice are impaired at familiarity-based object recognition, raising concerns regarding the validity of using these genetically modified mice to model recognition phenotypes observed in patients. This issue can be resolved in future animal studies by examining performance in different variants of the spontaneous recognition task-the standard, perirhinal cortex-dependent, object recognition task versus the hippocampus-dependent object-place recognition task-in order to see which of the two recognition mechanisms is more disrupted. © 2015 Elsevier Inc. All rights reserved.

  14. Continuity of visual and auditory rhythms influences sensorimotor coordination.

    Directory of Open Access Journals (Sweden)

    Manuel Varlet

    Full Text Available People often coordinate their movement with visual and auditory environmental rhythms. Previous research showed better performances when coordinating with auditory compared to visual stimuli, and with bimodal compared to unimodal stimuli. However, these results have been demonstrated with discrete rhythms and it is possible that such effects depend on the continuity of the stimulus rhythms (i.e., whether they are discrete or continuous. The aim of the current study was to investigate the influence of the continuity of visual and auditory rhythms on sensorimotor coordination. We examined the dynamics of synchronized oscillations of a wrist pendulum with auditory and visual rhythms at different frequencies, which were either unimodal or bimodal and discrete or continuous. Specifically, the stimuli used were a light flash, a fading light, a short tone and a frequency-modulated tone. The results demonstrate that the continuity of the stimulus rhythms strongly influences visual and auditory motor coordination. Participants' movement led continuous stimuli and followed discrete stimuli. Asymmetries between the half-cycles of the movement in term of duration and nonlinearity of the trajectory occurred with slower discrete rhythms. Furthermore, the results show that the differences of performance between visual and auditory modalities depend on the continuity of the stimulus rhythms as indicated by movements closer to the instructed coordination for the auditory modality when coordinating with discrete stimuli. The results also indicate that visual and auditory rhythms are integrated together in order to better coordinate irrespective of their continuity, as indicated by less variable coordination closer to the instructed pattern. Generally, the findings have important implications for understanding how we coordinate our movements with visual and auditory environmental rhythms in everyday life.

  15. Genetic and environmental influences on individual differences in cortisol level and circadian rhythm in middle childhood.

    Science.gov (United States)

    Van Hulle, Carol A; Shirtcliff, Elizabeth A; Lemery-Chalfant, Kathryn; Goldsmith, H Hill

    2012-06-01

    Individuals differ widely in cortisol output over the day, but the etiology of these individual differences remains poorly understood. Twin studies are useful for quantifying genetic and environmental influences on the variation in cortisol output, lending insight into underlying influences on the components of Hypothalamic-Pituitary-Adrenal (HPA) axis functioning. Salivary cortisol was assayed on 446 twin pairs (157 monozygotic, 289 dizygotic; ages 7-8). Parents helped youth collect saliva 30 min after waking, mid-afternoon, and 30 min prior to bedtime across 3 consecutive days. We used hierarchical linear modeling to extract predicted cortisol levels and to distinguish cortisol's diurnal rhythm using a slopes-as-outcome piecewise growth curve model; two slopes captured the morning-to-afternoon and afternoon-to-evening rhythm, respectively. Separate genetic models were then fit to cortisol level at waking, mid-afternoon, and evening as well as the diurnal rhythm across morning-to-afternoon and afternoon-to-evening hours. Three results from these analyses are striking. First, morning-to-afternoon cortisol level showed the highest additive genetic variance (heritability), consistent with prior research. Second, cortisol's diurnal rhythm had an additive genetic component, particularly across the morning-to-afternoon hours. In contrast, additive genetic variation did not significantly contribute to variation in afternoon-to-evening slope. Third, the majority of variance in cortisol concentration was associated with shared family environments. In summary, both genetic and environmental factors influence cortisol's circadian rhythm, and they do so differentially across the day. Published by Elsevier Inc.

  16. Modeling the emergence of circadian rhythms in a clock neuron network.

    Directory of Open Access Journals (Sweden)

    Luis Diambra

    Full Text Available Circadian rhythms in pacemaker cells persist for weeks in constant darkness, while in other types of cells the molecular oscillations that underlie circadian rhythms damp rapidly under the same conditions. Although much progress has been made in understanding the biochemical and cellular basis of circadian rhythms, the mechanisms leading to damped or self-sustained oscillations remain largely unknown. There exist many mathematical models that reproduce the circadian rhythms in the case of a single cell of the Drosophila fly. However, not much is known about the mechanisms leading to coherent circadian oscillation in clock neuron networks. In this work we have implemented a model for a network of interacting clock neurons to describe the emergence (or damping of circadian rhythms in Drosophila fly, in the absence of zeitgebers. Our model consists of an array of pacemakers that interact through the modulation of some parameters by a network feedback. The individual pacemakers are described by a well-known biochemical model for circadian oscillation, to which we have added degradation of PER protein by light and multiplicative noise. The network feedback is the PER protein level averaged over the whole network. In particular, we have investigated the effect of modulation of the parameters associated with (i the control of net entrance of PER into the nucleus and (ii the non-photic degradation of PER. Our results indicate that the modulation of PER entrance into the nucleus allows the synchronization of clock neurons, leading to coherent circadian oscillations under constant dark condition. On the other hand, the modulation of non-photic degradation cannot reset the phases of individual clocks subjected to intrinsic biochemical noise.

  17. Scheduled daily mating induces circadian anticipatory activity rhythms in the male rat.

    Directory of Open Access Journals (Sweden)

    Glenn J Landry

    Full Text Available Daily schedules of limited access to food, palatable high calorie snacks, water and salt can induce circadian rhythms of anticipatory locomotor activity in rats and mice. All of these stimuli are rewarding, but whether anticipation can be induced by neural correlates of reward independent of metabolic perturbations associated with manipulations of food and hydration is unclear. Three experiments were conducted to determine whether mating, a non-ingestive behavior that is potently rewarding, can induce circadian anticipatory activity rhythms in male rats provided scheduled daily access to steroid-primed estrous female rats. In Experiment 1, rats anticipated access to estrous females in the mid-light period, but also exhibited post-coital eating and running. In Experiment 2, post-coital eating and running were prevented and only a minority of rats exhibited anticipation. Rats allowed to see and smell estrous females showed no anticipation. In both experiments, all rats exhibited sustained behavioral arousal and multiple mounts and intromissions during every session, but ejaculated only every 2-3 days. In Experiment 3, the rats were given more time with individual females, late at night for 28 days, and then in the midday for 28 days. Ejaculation rates increased and anticipation was robust to night sessions and significant although weaker to day sessions. The anticipation rhythm persisted during 3 days of constant dark without mating. During anticipation of nocturnal mating, the rats exhibited a significant preference for a tube to the mating cage over a tube to a locked cage with mating cage litter. This apparent place preference was absent during anticipation of midday mating, which may reflect a daily rhythm of sexual reward. The results establish mating as a reward stimulus capable of inducing circadian rhythms of anticipatory behavior in the male rat, and reveal a critical role for ejaculation, a modulatory role for time of day, and a

  18. Scheduled daily mating induces circadian anticipatory activity rhythms in the male rat.

    Science.gov (United States)

    Landry, Glenn J; Opiol, Hanna; Marchant, Elliott G; Pavlovski, Ilya; Mear, Rhiannon J; Hamson, Dwayne K; Mistlberger, Ralph E

    2012-01-01

    Daily schedules of limited access to food, palatable high calorie snacks, water and salt can induce circadian rhythms of anticipatory locomotor activity in rats and mice. All of these stimuli are rewarding, but whether anticipation can be induced by neural correlates of reward independent of metabolic perturbations associated with manipulations of food and hydration is unclear. Three experiments were conducted to determine whether mating, a non-ingestive behavior that is potently rewarding, can induce circadian anticipatory activity rhythms in male rats provided scheduled daily access to steroid-primed estrous female rats. In Experiment 1, rats anticipated access to estrous females in the mid-light period, but also exhibited post-coital eating and running. In Experiment 2, post-coital eating and running were prevented and only a minority of rats exhibited anticipation. Rats allowed to see and smell estrous females showed no anticipation. In both experiments, all rats exhibited sustained behavioral arousal and multiple mounts and intromissions during every session, but ejaculated only every 2-3 days. In Experiment 3, the rats were given more time with individual females, late at night for 28 days, and then in the midday for 28 days. Ejaculation rates increased and anticipation was robust to night sessions and significant although weaker to day sessions. The anticipation rhythm persisted during 3 days of constant dark without mating. During anticipation of nocturnal mating, the rats exhibited a significant preference for a tube to the mating cage over a tube to a locked cage with mating cage litter. This apparent place preference was absent during anticipation of midday mating, which may reflect a daily rhythm of sexual reward. The results establish mating as a reward stimulus capable of inducing circadian rhythms of anticipatory behavior in the male rat, and reveal a critical role for ejaculation, a modulatory role for time of day, and a potential confound role for

  19. Altered Heart Rhythm Dynamics in Very Low Birth Weight Infants With Impending Intraventricular Hemorrhage

    Science.gov (United States)

    Tuzcu, Volkan; Nas, Selman; Ulusar, Umit; Ugur, Ahmet; Kaiser, Jeffrey R.

    2010-01-01

    OBJECTIVE Intraventricular hemorrhage remains an important problem among very low birth weight infants and may result in long-term neurodevelopmental disabilities. Neonatologists have been unable to accurately predict impending intraventricular hemorrhage. Because alterations in the autonomic nervous system’s control of heart rhythm have been associated with intraventricular hemorrhage after its development, we sought to determine if early subtle alterations of heart rhythm could be predictive of impending intraventricular hemorrhage in very low birth weight infants. METHODS This case-control study included 10 newborn very low birth weight infants with intraventricular hemorrhage (5 grade IV, 4 grade III, and 1 grade II) and 14 control infants without intraventricular hemorrhage. Heart rhythm data from the first day of life before the development of intraventricular hemorrhage were evaluated. Detrended fluctuation analysis, a nonlinear fractal heart rate variability method, was used to assess the fractal dynamics of the heart rhythm. Fractal scaling exponents were calculated by using this analysis. RESULTS Twenty-four infants (mean ± SD, birth weight: 845 ± 213g: gestational age: 26.1 ± 1.9 weeks) participated in the study. The short-term scaling exponent was significantly larger in infants who later developed intraventricular hemorrhage compared with those who did not (0.60 ± 0.1 vs 0.45 ± 0.1). A value of 0.52 resulted in 70% sensitivity and positive predictive value and 79% specificity and negative predictive value. The short-term scaling exponent was the only significant predictor of intraventricular hemorrhage. CONCLUSIONS Fractal dynamics of the heart rhythm is significantly altered in very low birth weight infants before developing intraventricular hemorrhage and may be predictive of impending intraventricular hemorrhage. PMID:19255007

  20. Different melatonin rhythms and sleep-wake rhythms in patients on peritoneal dialysis, daytime hemodialysis and nocturnal hemodialysis

    NARCIS (Netherlands)

    Koch, B.C.P.; Nagtegaal, J.E.; Hagen, E.C.; ter Wee, P.M.; Kerkhof, G.A.

    2010-01-01

    Background: Little comparative data on sleep-wake rhythms in different dialysis groups exist. The aim of this study was to investigate sleep-wake parameters measured with actigraphy and sleep questionnaires as well as melatonin rhythms in automated peritoneal dialysis, conventional daytime

  1. Wheel running improves REM sleep and attenuates stress-induced flattening of diurnal rhythms in F344 rats.

    Science.gov (United States)

    Thompson, Robert S; Roller, Rachel; Greenwood, Benjamin N; Fleshner, Monika

    2016-05-01

    Regular physical activity produces resistance to the negative health consequences of stressor exposure. One way that exercise may confer stress resistance is by reducing the impact of stress on diurnal rhythms and sleep; disruptions of which contribute to stress-related disease including mood disorders. Given the link between diurnal rhythm disruptions and stress-related disorders and that exercise both promotes stress resistance and is a powerful non-photic biological entrainment cue, we tested if wheel running could reduce stress-induced disruptions of sleep/wake behavior and diurnal rhythms. Adult, male F344 rats with or without access to running wheels were instrumented for biotelemetric recording of diurnal rhythms of locomotor activity, heart rate, core body temperature (CBT), and sleep (i.e. REM, NREM, and WAKE) in the presence of a 12 h light/dark cycle. Following 6 weeks of sedentary or exercise conditions, rats were exposed to an acute stressor known to disrupt diurnal rhythms and produce behaviors associated with mood disorders. Prior to stressor exposure, exercise rats had higher CBT, more locomotor activity during the dark cycle, and greater %REM during the light cycle relative to sedentary rats. NREM and REM sleep were consolidated immediately following peak running to a greater extent in exercise, compared to sedentary rats. In response to stressor exposure, exercise rats expressed higher stress-induced hyperthermia than sedentary rats. Stressor exposure disrupted diurnal rhythms in sedentary rats; and wheel running reduced these effects. Improvements in sleep and reduced diurnal rhythm disruptions following stress could contribute to the health promoting and stress protective effects of exercise.

  2. Neuropeptide signaling differentially affects phase maintenance and rhythm generation in SCN and extra-SCN circadian oscillators.

    Science.gov (United States)

    Hughes, Alun T L; Guilding, Clare; Piggins, Hugh D

    2011-04-29

    Circadian rhythms in physiology and behavior are coordinated by the brain's dominant circadian pacemaker located in the suprachiasmatic nuclei (SCN) of the hypothalamus. Vasoactive intestinal polypeptide (VIP) and its receptor, VPAC(2), play important roles in the functioning of the SCN pacemaker. Mice lacking VPAC(2) receptors (Vipr2(-/-)) express disrupted behavioral and metabolic rhythms and show altered SCN neuronal activity and clock gene expression. Within the brain, the SCN is not the only site containing endogenous circadian oscillators, nor is it the only site of VPAC(2) receptor expression; both VPAC(2) receptors and rhythmic clock gene/protein expression have been noted in the arcuate (Arc) and dorsomedial (DMH) nuclei of the mediobasal hypothalamus, and in the pituitary gland. The functional role of VPAC(2) receptors in rhythm generation and maintenance in these tissues is, however, unknown. We used wild type (WT) and Vipr2(-/-) mice expressing a luciferase reporter (PER2::LUC) to investigate whether circadian rhythms in the clock gene protein PER2 in these extra-SCN tissues were compromised by the absence of the VPAC(2) receptor. Vipr2(-/-) SCN cultures expressed significantly lower amplitude PER2::LUC oscillations than WT SCN. Surprisingly, in Vipr2(-/-) Arc/ME/PT complex (Arc, median eminence and pars tuberalis), DMH and pituitary, the period, amplitude and rate of damping of rhythms were not significantly different to WT. Intriguingly, while we found WT SCN and Arc/ME/PT tissues to maintain a consistent circadian phase when cultured, the phase of corresponding Vipr2(-/-) cultures was reset by cull/culture procedure. These data demonstrate that while the main rhythm parameters of extra-SCN circadian oscillations are maintained in Vipr2(-/-) mice, the ability of these oscillators to resist phase shifts is compromised. These deficiencies may contribute towards the aberrant behavior and metabolism associated with Vipr2(-/-) animals. Further, our data

  3. Atrial Fibrillation Management Strategies in Routine Clinical Practice: Insights from the International RealiseAF Survey

    Science.gov (United States)

    Chiang, Chern-En; Naditch-Brûlé, Lisa; Brette, Sandrine; Silva-Cardoso, José; Gamra, Habib; Murin, Jan; Zharinov, Oleg J.; Steg, Philippe Gabriel

    2016-01-01

    Background Atrial fibrillation (AF) can be managed with rhythm- or rate-control strategies. There are few data from routine clinical practice on the frequency with which each strategy is used and their correlates in terms of patients’ clinical characteristics, AF control, and symptom burden. Methods RealiseAF was an international, cross-sectional, observational survey of 11,198 patients with AF. The aim of this analysis was to describe patient profiles and symptoms according to the AF management strategy used. A multivariate logistic regression identified factors associated with AF management strategy at the end of the visit. Results Among 10,497 eligible patients, 53.7% used a rate-control strategy, compared with 34.5% who used a rhythm-control strategy. In 11.8% of patients, no clear strategy was stated. The proportion of patients with AF-related symptoms (EHRA Class > = II) was 78.1% (n = 4396/5630) for those using a rate-control strategy vs. 67.8% for those using a rhythm-control strategy (pstrategy. A change in strategy was infrequent, even in patients with European Heart Rhythm Association (EHRA) Class > = II. Conclusions In the RealiseAF routine clinical practice survey, rate control was more commonly used than rhythm control, and a change in strategy was uncommon, even in symptomatic patients. In almost 12% of patients, no clear strategy was stated. Physician awareness regarding optimal management strategies for AF may be improved. PMID:26800084

  4. Cross-cultural influences on rhythm processing: reproduction, discrimination, and beat tapping.

    Science.gov (United States)

    Cameron, Daniel J; Bentley, Jocelyn; Grahn, Jessica A

    2015-01-01

    The structures of musical rhythm differ between cultures, despite the fact that the ability to entrain movement to musical rhythm occurs in virtually all individuals across cultures. To measure the influence of culture on rhythm processing, we tested East African and North American adults on perception, production, and beat tapping for rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were the same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced by the culture of the participant and the culture of the rhythm. Specifically, we predicted that a participant's ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than for unfamiliar rhythms. Moreover, there were differences between the two participant groups, and between the two types of rhythms, in the metrical level selected for beat tapping. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  5. Tissue-Specific Dissociation of Diurnal Transcriptome Rhythms During Sleep Restriction in Mice.

    Science.gov (United States)

    Husse, Jana; Kiehn, Jana-Thabea; Barclay, Johanna L; Naujokat, Nadine; Meyer-Kovac, Judit; Lehnert, Hendrik; Oster, Henrik

    2017-06-01

    Shortened or mistimed sleep affects metabolic homeostasis, which may in part be mediated by dysregulation of endogenous circadian clocks. In this study, we assessed the contribution of sleep disruption to metabolic dysregulation by analysing diurnal transcriptome regulation in metabolic tissues of mice subjected to a sleep restriction (SR) paradigm. Male mice were subjected to 2 × 5 days of SR with enforced waking during the first 6 hours of the light phase. SR and control mice were sacrificed at different time points of the day and RNA preparations from the mediobasal hypothalamus (MBH), liver, and epididymal white adipose tissue (eWAT) were subjected to whole-genome microarray hybridization. Transcriptional rhythms were associated with changes in behavioral and physiological parameters such as sleep, body temperature, and food intake. Rhythm detection was performed with CircWave and transcription profiles were compared by 2-way analysis of variance and t-tests with Benjamini-Hochberg corrections. Clock gene rhythms were blunted in all tissues, while transcriptome regulation was associated with either clock gene expression, sleep patterns, or food intake in a tissue-specific manner. Clock gene expression was associated with apoptosis pathways in the MBH and with tumor necrosis factor alpha signalling in liver. Food intake-associated genes included cilium movement genes in the MBH and lipid metabolism-associated transcripts in liver. In mice, repeated SR profoundly alters behavioral and molecular diurnal rhythms, disrupting essential signalling pathways in MBH, liver, and eWAT, which may underlie the metabolic and cognitive disturbances observed in sleep-restricted humans such as shift workers.

  6. Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation.

    Science.gov (United States)

    Lafuente-Lafuente, Carmelo; Valembois, Lucie; Bergmann, Jean-François; Belmin, Joël

    2015-03-28

    Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation frequently recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear. This is an update of a review previously published in 2008 and 2012. To determine in patients who have recovered sinus rhythm after having atrial fibrillation, the effects of long-term treatment with antiarrhythmic drugs on death, stroke, embolism, drug adverse effects and recurrence of atrial fibrillation. We updated the searches of CENTRAL in The Cochrane Library (2013, Issue 12 of 12), MEDLINE (to January 2014) and EMBASE (to January 2014). The reference lists of retrieved articles, recent reviews and meta-analyses were checked. Two independent authors selected randomised controlled trials comparing any antiarrhythmic drug with a control (no treatment, placebo, drugs for rate control) or with another antiarrhythmic drug in adults who had atrial fibrillation and in whom sinus rhythm was restored. Post-operative atrial fibrillation was excluded. Two authors independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up. In this update three new studies, with 534 patients, were included making a total of 59 included studies comprising 21,305 patients. All included studies were randomised controlled trials. Allocation concealment was adequate in 17 trials, it was unclear in the remaining 42 trials. Risk of bias was assessed in all domains only in the trials included in this update.Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95% CI) 1.03 to 5.59, number needed to treat to harm (NNTH) 109, 95% CI 34 to 4985) and sotalol (OR 2.23, 95% CI 1.1 to 4.50, NNTH 169, 95% CI 60 to 2068) were associated with increased all

  7. Effects of Pacifier and Taste on Swallowing, Esophageal Motility, Transit and Respiratory Rhythm in Human Neonates

    Science.gov (United States)

    Shubert, Theresa R.; Sitaram, Swetha; Jadcherla, Sudarshan R.

    2015-01-01

    Background Pacifier use is widely prevalent globally despite hygienic concerns and uncertain mechanistic effects on swallowing or airway safety. Aims The effects of pacifier and taste interventions on pharyngo-esophageal motility, bolus transit and respiratory rhythms were investigated by determining the upper esophageal sphincter (UES), esophageal body, esophagogastric junction (EGJ) motor patterns as well as deglutition apnea, respiratory rhythm disturbances and esophageal bolus clearance. Methods Fifteen infants (6 males; median gestation 31 wks and birth weight 1.4 kg) underwent high resolution impedance manometry at 43 (41-44) weeks post-menstrual age. Manometric, respiratory, and impedance characteristics of spontaneous swallows, pacifier associated dry swallowing and taste (pacifier dipped in 3% sucrose) associated swallowing were analyzed. Linear mixed and generalized estimating equation models were used. Data are presented as mean ± SEM, %, or median (IQR). Key Results Pharyngo-esophageal motility, respiratory, and impedance characteristics of 209 swallows were analyzed (85 spontaneous swallows, 63 pacifier associated dry swallows, 61 taste associated swallows). Basal UES and EGJ pressures decreased upon pacifier (P<0.05) and taste interventions (P<0.05); however, esophageal motility, respiratory rhythm, and impedance transit characteristics were similar with both interventions. Conclusions and Inferences Oral stimulus with pacifier or taste interventions decreases UES and EGJ basal pressure, but has no effects on pharyngo-esophageal motility, airway interactions, or esophageal bolus transit. A decrease in central parasympathetic-cholinergic excitatory drive is likely responsible for the basal effects. PMID:26727930

  8. Effect of Pilates Training on Alpha Rhythm

    Directory of Open Access Journals (Sweden)

    Zhijie Bian

    2013-01-01

    Full Text Available In this study, the effect of Pilates training on the brain function was investigated through five case studies. Alpha rhythm changes during the Pilates training over the different regions and the whole brain were mainly analyzed, including power spectral density and global synchronization index (GSI. It was found that the neural network of the brain was more active, and the synchronization strength reduced in the frontal and temporal regions due to the Pilates training. These results supported that the Pilates training is very beneficial for improving brain function or intelligence. These findings maybe give us some line evidence to suggest that the Pilates training is very helpful for the intervention of brain degenerative diseases and cogitative dysfunction rehabilitation.

  9. Choreographing Compassion: A Clinical Adventure of Rhythms.

    Science.gov (United States)

    Yopst, Charles George

    2015-06-01

    Compassion is a primary catalyst motivating positive human relationships, especially of those less fortunate. Our rhythms Expand-Contract of our own non-verbal body joints movements and of the law of counter-balance, enable us to identify which of nine innate affects-emotions is directing the body's movements. With this reading, a trained person can synchronize choreography of these into fully authentic compassion between two or more persons. Primary references for this are the late Silvan S. Tomkins's four volumes "Affect Imagery Consciousness," and choreographers the late Rudolf Laban, Warren Lamb, Irmgard Bartenieff, and Marian Chace. Professionals, clinicians, and laity counselors can all use these. © The Author(s) 2015.

  10. Circadian Rhythms, Sleep, and Disorders of Aging.

    Science.gov (United States)

    Mattis, Joanna; Sehgal, Amita

    2016-04-01

    Sleep-wake cycles are known to be disrupted in people with neurodegenerative disorders. These findings are now supported by data from animal models for some of these disorders, raising the question of whether the disrupted sleep/circadian regulation contributes to the loss of neural function. As circadian rhythms and sleep consolidation also break down with normal aging, changes in these may be part of what makes aging a risk factor for disorders like Alzheimer's disease (AD). Mechanisms underlying the connection between circadian/sleep dysregulation and neurodegeneration remain unclear, but several recent studies provide interesting possibilities. While mechanistic analysis is under way, it is worth considering treatment of circadian/sleep disruption as a means to alleviate symptoms of neurodegenerative disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The Psychology of Music: Rhythm and Movement.

    Science.gov (United States)

    Levitin, Daniel J; Grahn, Jessica A; London, Justin

    2018-01-04

    The urge to move to music is universal among humans. Unlike visual art, which is manifest across space, music is manifest across time. When listeners get carried away by the music, either through movement (such as dancing) or through reverie (such as trance), it is usually the temporal qualities of the music-its pulse, tempo, and rhythmic patterns-that put them in this state. In this article, we review studies addressing rhythm, meter, movement, synchronization, entrainment, the perception of groove, and other temporal factors that constitute a first step to understanding how and why music literally moves us. The experiments we review span a range of methodological techniques, including neuroimaging, psychophysics, and traditional behavioral experiments, and we also summarize the current studies of animal synchronization, engaging an evolutionary perspective on human rhythmic perception and cognition.

  12. [Sleep rhythm disturbances in Alzheimer's disease].

    Science.gov (United States)

    Onen, F; Onen, S-H

    2003-03-01

    Sleep-wake rhythm disturbances observed in Alzheimer's disease are correlated with the severity of cognitive impairment and often result in institutionalization. These disturbances are also a major cause of psychotropic medication misuse. We report age-related physiologic and disease related pathologic changes in sleep-wake rhythms and propose chronobiological treatment approaches in patients with Alzheimer's disease. Alzheimer patients show a greater breakdown of the circadian sleep-wake cycle compared to similarly aged non demented controls. Demented patients spend their nights in a state of frequent restlessness and their days in a state of frequent sleepiness. These sleep-wake disturbances became increasingly more marked with progression of the disease. The architecture of sleep in Alzheimer's disease is marked by further decreases of slow wave sleep (SWS) and rapid eye movement (REM) sleep, and increases of time and frequency of awakening compared to age-matched control subjects. The sleep-wake disturbances in elderly people and particularly Alzheimer patients may result from changes at different levels: a reduction of environmental synchronizers or their perception, a lack of mental and physical activity, an age or disease related anatomical changes with loss of functionality of the biological clock(s). In Alzheimer patients, controlling sleep-wake disturbances with sedative drugs often increases both sleep disturbance and cognitive dysfunction. A chronobiological approach with bright-light therapy, melatonin administration, restricted time in bed, and diurnal activity may be an interesting therapeutic alternative in the management of sleep-wake disorders in Alzheimer patients. The aim of these therapeutics is to improve sleep and diurnal activity and consequently to increase the quality of life in Alzheimer patients.

  13. Biological and psychological rhythms: an integrative approach to rhythm disturbances in autistic disorder.

    Science.gov (United States)

    Botbol, Michel; Cabon, Philippe; Kermarrec, Solenn; Tordjman, Sylvie

    2013-09-01

    Biological rhythms are crucial phenomena that are perfect examples of the adaptation of organisms to their environment. A considerable amount of work has described different types of biological rhythms (from circadian to ultradian), individual differences in their patterns and the complexity of their regulation. In particular, the regulation and maturation of the sleep-wake cycle have been thoroughly studied. Its desynchronization, both endogenous and exogenous, is now well understood, as are its consequences for cognitive impairments and health problems. From a completely different perspective, psychoanalysts have shown a growing interest in the rhythms of psychic life. This interest extends beyond the original focus of psychoanalysis on dreams and the sleep-wake cycle, incorporating central theoretical and practical psychoanalytic issues related to the core functioning of the psychic life: the rhythmic structures of drive dynamics, intersubjective developmental processes and psychic containment functions. Psychopathological and biological approaches to the study of infantile autism reveal the importance of specific biological and psychological rhythmic disturbances in this disorder. Considering data and hypotheses from both perspectives, this paper proposes an integrative approach to the study of these rhythmic disturbances and offers an etiopathogenic hypothesis based on this integrative approach. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Heart rate and outcome in heart failure with reduced ejection fraction: Differences between atrial fibrillation and sinus rhythm-A CIBIS II analysis.

    Science.gov (United States)

    Mulder, Bart A; Damman, Kevin; Van Veldhuisen, Dirk J; Van Gelder, Isabelle C; Rienstra, Michiel

    2017-09-01

    Heart rate has been associated with prognosis in patients with heart failure with reduced ejection fraction (HFREF) and sinus rhythm; whether this also holds true in patients with atrial fibrillation (AF) is unknown. To evaluate cardiac rhythm and baseline heart rate and the influence of outcome in patients with HFREF enrolled in the Cardiac Insufficiency Bisoprolol Study II. In total, 2539 patients were stratified according to their baseline heart rhythm (AF or sinus rhythm) and into quartiles of heart rate (≤70 bpm, 71-78 bpm, 79-90 bpm, and >90 bpm). The primary outcome was all-cause mortality. Mean follow-up was 1.3 years. Mean age was 61 years, mean left ventricular ejection fraction was 28%, and 80% were male. A total of 521 (21%) patients had AF at baseline. The risk associated with all-cause mortality for each 5 bpm increase in heart rate in patients with sinus rhythm (hazard ratio [HR]: 1.06, 95% confidence interval [CI]: 1.01-1.11, P = 0.012) was significantly different from those with AF (HR: 1.00, 95% CI: 0.94-1.07, P = 0.90, P for interaction = 0.041). The risk associated with higher heart rate in sinus rhythm was primarily attributable to excess risk in the highest quartile (HR: 1.64, 95% CI: 1.18-2.30, P = 0.003). Allocation to bisoprolol did not modify the interaction between heart rate, rhythm and outcome. In HFREF patients with AF, a higher heart rate is not associated with increased event rates in contrast to HFREF patients with sinus rhythm. © 2017 Wiley Periodicals, Inc.

  15. Cross-Cultural Influences on Rhythm Processing: Reproduction, Discrimination, and Beat Tapping

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2015-04-01

    Full Text Available The structures of musical rhythm differ between cultures, despite the fact that the ability to synchronize one’s movements to musical rhythms appears to be universal. To measure the influence of culture on rhythm processing, we tested East African and North American adults on the perception, production, and beat tapping of rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced both by the culture of the participant and by the culture of the rhythm. Specifically, we predicted that a participant’s ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than unfamiliar rhythms. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  16. Rhythm perception and production by the bottlenose dolphin

    Science.gov (United States)

    Harley, Heidi E.; Crowell, Sara E.; Fellner, Wendi; Odell, Kim; Larsen-Plott, Leslie

    2005-09-01

    Rhythm is an important component of many natural communication systems, but it has rarely been the focus of laboratory studies of nonhuman species. Recent cognitive studies with a bottlenose dolphin confirm that a dolphin can discriminate among six different 14-kHz 4-s acoustic rhythms at 94% accuracy, and can transfer that discrimination across multiple frequency (93%) and tempo (16%-93%) shifts. In addition, a dolphin has learned to produce six different rhythms in an object-labeling paradigm. Original training required the dolphin to produce the rhythms using a pneumatic switch that led to the in-air projection of computer-generated tones. However, the dolphin spontaneously began to produce the rhythms vocally as well. To date, the dolphin has accurately labeled five objects with unique rhythms at 87% accuracy using the switch and at 83% accuracy using his own vocalizations. Confusions at the various tempos in the perception study and the variability of some characteristics and stability of others in the production study provide insight into how dolphins represent rhythm and have implications for natural communication in this species.

  17. Neural networks for beat perception in musical rhythm

    Directory of Open Access Journals (Sweden)

    Edward W Large

    2015-11-01

    Full Text Available Entrainment of cortical rhythms to acoustic rhythms has been hypothesized to be the neural correlate of pulse and meter perception in music. Dynamic attending theory first proposed synchronization of endogenous perceptual rhythms nearly forty years ago, but only recently has the pivotal role of neural synchrony been demonstrated. Significant progress has since been made in understanding the role of neural oscillations and the neural structures that support synchronized responses to musical rhythm. Synchronized neural activity has been observed in auditory and motor networks, and has been linked with attentional allocation and movement coordination. Here we describe a neurodynamic model that shows how self-organization of oscillations in interacting sensory and motor networks could be responsible for the formation of the pulse percept in complex rhythms. We test the model's prediction that pulse can be perceived at a frequency for which no spectral energy is present in the amplitude envelope of the acoustic rhythm. The result provides a theoretical link between oscillatory neurodynamics and the induction of pulse and meter in musical rhythm.

  18. Neural Networks for Beat Perception in Musical Rhythm.

    Science.gov (United States)

    Large, Edward W; Herrera, Jorge A; Velasco, Marc J

    2015-01-01

    Entrainment of cortical rhythms to acoustic rhythms has been hypothesized to be the neural correlate of pulse and meter perception in music. Dynamic attending theory first proposed synchronization of endogenous perceptual rhythms nearly 40 years ago, but only recently has the pivotal role of neural synchrony been demonstrated. Significant progress has since been made in understanding the role of neural oscillations and the neural structures that support synchronized responses to musical rhythm. Synchronized neural activity has been observed in auditory and motor networks, and has been linked with attentional allocation and movement coordination. Here we describe a neurodynamic model that shows how self-organization of oscillations in interacting sensory and motor networks could be responsible for the formation of the pulse percept in complex rhythms. In a pulse synchronization study, we test the model's key prediction that pulse can be perceived at a frequency for which no spectral energy is present in the amplitude envelope of the acoustic rhythm. The result shows that participants perceive the pulse at the theoretically predicted frequency. This model is one of the few consistent with neurophysiological evidence on the role of neural oscillation, and it explains a phenomenon that other computational models fail to explain. Because it is based on a canonical model, the predictions hold for an entire family of dynamical systems, not only a specific one. Thus, this model provides a theoretical link between oscillatory neurodynamics and the induction of pulse and meter in musical rhythm.

  19. A Reliable Method for Rhythm Analysis during Cardiopulmonary Resuscitation

    Directory of Open Access Journals (Sweden)

    U. Ayala

    2014-01-01

    Full Text Available Interruptions in cardiopulmonary resuscitation (CPR compromise defibrillation success. However, CPR must be interrupted to analyze the rhythm because although current methods for rhythm analysis during CPR have high sensitivity for shockable rhythms, the specificity for nonshockable rhythms is still too low. This paper introduces a new approach to rhythm analysis during CPR that combines two strategies: a state-of-the-art CPR artifact suppression filter and a shock advice algorithm (SAA designed to optimally classify the filtered signal. Emphasis is on designing an algorithm with high specificity. The SAA includes a detector for low electrical activity rhythms to increase the specificity, and a shock/no-shock decision algorithm based on a support vector machine classifier using slope and frequency features. For this study, 1185 shockable and 6482 nonshockable 9-s segments corrupted by CPR artifacts were obtained from 247 patients suffering out-of-hospital cardiac arrest. The segments were split into a training and a test set. For the test set, the sensitivity and specificity for rhythm analysis during CPR were 91.0% and 96.6%, respectively. This new approach shows an important increase in specificity without compromising the sensitivity when compared to previous studies.

  20. Human adipose tissue expresses intrinsic circadian rhythm in insulin sensitivity.

    Science.gov (United States)

    Carrasco-Benso, Maria P; Rivero-Gutierrez, Belen; Lopez-Minguez, Jesus; Anzola, Andrea; Diez-Noguera, Antoni; Madrid, Juan A; Lujan, Juan A; Martínez-Augustin, Olga; Scheer, Frank A J L; Garaulet, Marta

    2016-09-01

    In humans, insulin sensitivity varies according to time of day, with decreased values in the evening and at night. Mechanisms responsible for the diurnal variation in insulin sensitivity are unclear. We investigated whether human adipose tissue (AT) expresses intrinsic circadian rhythms in insulin sensitivity that could contribute to this phenomenon. Subcutaneous and visceral AT biopsies were obtained from extremely obese participants (body mass index, 41.8 ± 6.3 kg/m(2); 46 ± 11 y) during gastric-bypass surgery. To assess the rhythm in insulin signaling, AKT phosphorylation was determined every 4 h over 24 h in vitro in response to different insulin concentrations (0, 1, 10, and 100 nM). Data revealed that subcutaneous AT exhibited robust circadian rhythms in insulin signaling (P circadian rhythms were detected in visceral AT (P = 0.643). Here, we demonstrate the relevance of the time of the day for how sensitive AT is to the effects of insulin. Subcutaneous AT shows an endogenous circadian rhythm in insulin sensitivity that could provide an underlying mechanism for the daily rhythm in systemic insulin sensitivity.-Carrasco-Benso, M. P., Rivero-Gutierrez, B., Lopez-Minguez, J., Anzola, A., Diez-Noguera, A., Madrid, J. A., Lujan, J. A., Martínez-Augustin, O., Scheer, F. A. J. L., Garaulet, M. Human adipose tissue expresses intrinsic circadian rhythm in insulin sensitivity. © FASEB.

  1. Fetal ethanol exposure disrupts the daily rhythms of splenic granzyme B, IFN-gamma, and NK cell cytotoxicity in adulthood.

    Science.gov (United States)

    Arjona, Alvaro; Boyadjieva, Nadka; Kuhn, Peter; Sarkar, Dipak K

    2006-06-01

    Circadian (and daily) rhythms are physiological events that oscillate with a 24-hour period. Circadian disruptions may hamper the immune response against infection and cancer. Several immune mechanisms, such as natural killer (NK) cell function, follow a daily rhythm. Although ethanol is known to be a potent toxin for many systems in the developing fetus, including the immune system, the long-term effects of fetal ethanol exposure on circadian immune function have not been explored. Daily rhythms of cytotoxic factors (granzyme B and perforin), interferon-gamma (IFN-gamma), and NK cell cytotoxic activity were determined in the spleens of adult male rats obtained from mothers who were fed during pregnancy with chow food or an ethanol-containing liquid diet or pair-fed an isocaloric liquid diet. We found that adult rats exposed to ethanol during their fetal life showed a significant alteration in the physiological rhythms of granzyme B and IFN-gamma that was associated with decreased NK cell cytotoxic activity. These data suggest that fetal ethanol exposure causes a permanent alteration of specific immune rhythms that may in part underlie the immune impairment observed in children prenatally exposed to alcohol.

  2. Unexpected diversity in socially synchronized rhythms of shorebirds.

    Science.gov (United States)

    Bulla, Martin; Valcu, Mihai; Dokter, Adriaan M; Dondua, Alexei G; Kosztolányi, András; Rutten, Anne L; Helm, Barbara; Sandercock, Brett K; Casler, Bruce; Ens, Bruno J; Spiegel, Caleb S; Hassell, Chris J; Küpper, Clemens; Minton, Clive; Burgas, Daniel; Lank, David B; Payer, David C; Loktionov, Egor Y; Nol, Erica; Kwon, Eunbi; Smith, Fletcher; Gates, H River; Vitnerová, Hana; Prüter, Hanna; Johnson, James A; St Clair, James J H; Lamarre, Jean-François; Rausch, Jennie; Reneerkens, Jeroen; Conklin, Jesse R; Burger, Joanna; Liebezeit, Joe; Bêty, Joël; Coleman, Jonathan T; Figuerola, Jordi; Hooijmeijer, Jos C E W; Alves, José A; Smith, Joseph A M; Weidinger, Karel; Koivula, Kari; Gosbell, Ken; Exo, Klaus-Michael; Niles, Larry; Koloski, Laura; McKinnon, Laura; Praus, Libor; Klaassen, Marcel; Giroux, Marie-Andrée; Sládeček, Martin; Boldenow, Megan L; Goldstein, Michael I; Šálek, Miroslav; Senner, Nathan; Rönkä, Nelli; Lecomte, Nicolas; Gilg, Olivier; Vincze, Orsolya; Johnson, Oscar W; Smith, Paul A; Woodard, Paul F; Tomkovich, Pavel S; Battley, Phil F; Bentzen, Rebecca; Lanctot, Richard B; Porter, Ron; Saalfeld, Sarah T; Freeman, Scott; Brown, Stephen C; Yezerinac, Stephen; Székely, Tamás; Montalvo, Tomás; Piersma, Theunis; Loverti, Vanessa; Pakanen, Veli-Matti; Tijsen, Wim; Kempenaers, Bart

    2016-12-01

    The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators. Individuals can temporally segregate their daily activities (for example, prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (for example, group foraging, communal defence, pairs reproducing or caring for offspring). The behavioural rhythms that emerge from such social synchronization and the underlying evolutionary and ecological drivers that shape them remain poorly understood. Here we investigate these rhythms in the context of biparental care, a particularly sensitive phase of social synchronization where pair members potentially compromise their individual rhythms. Using data from 729 nests of 91 populations of 32 biparentally incubating shorebird species, where parents synchronize to achieve continuous coverage of developing eggs, we report remarkable within- and between-species diversity in incubation rhythms. Between species, the median length of one parent's incubation bout varied from 1-19 h, whereas period length-the time in which a parent's probability to incubate cycles once between its highest and lowest value-varied from 6-43 h. The length of incubation bouts was unrelated to variables reflecting energetic demands, but species relying on crypsis (the ability to avoid detection by other animals) had longer incubation bouts than those that are readily visible or who actively protect their nest against predators. Rhythms entrainable to the 24-h light-dark cycle were less prevalent at high latitudes and absent in 18 species. Our results indicate that even under similar environmental conditions and despite 24-h environmental cues, social

  3. Circadian rhythms in human performance and mood under constant conditions

    Science.gov (United States)

    Monk, T. H.; Buysse, D. J.; Reynolds, C. F. 3rd; Berga, S. L.; Jarrett, D. B.; Begley, A. E.; Kupfer, D. J.

    1997-01-01

    This study explored the relationship between circadian performance rhythms and rhythms in rectal temperature, plasma cortisol, plasma melatonin, subjective alertness and well-being. Seventeen healthy young adults were studied under 36 h of 'unmasking' conditions (constant wakeful bedrest, temporal isolation, homogenized 'meals') during which rectal temperatures were measured every minute, and plasma cortisol and plasma melatonin measured every 20 min. Hourly subjective ratings of global vigour (alertness) and affect (well-being) were obtained followed by one of two performance batteries. On odd-numbered hours performance (speed and accuracy) of serial search, verbal reasoning and manual dexterity tasks was assessed. On even-numbered hours, performance (% hits, response speed) was measured at a 25-30 min visual vigilance task. Performance of all tasks (except search accuracy) showed a significant time of day variation usually with a nocturnal trough close to the trough in rectal temperature. Performance rhythms appeared not to reliably differ with working memory load. Within subjects, predominantly positive correlations emerged between good performance and higher temperatures and better subjective alertness; predominantly negative correlations between good performance and higher plasma levels of cortisol and melatonin. Temperature and cortisol rhythms correlated with slightly more performance measures (5/7) than did melatonin rhythms (4/7). Global vigour correlated about as well with performance (5/7) as did temperature, and considerably better than global affect (1/7). In conclusion: (1) between-task heterogeneity in circadian performance rhythms appeared to be absent when the sleep/wake cycle was suspended; (2) temperature (positively), cortisol and melatonin (negatively) appeared equally good as circadian correlates of performance, and (3) subjective alertness correlated with performance rhythms as well as (but not better than) body temperature, suggesting that

  4. Pacing as a Treatment for Reflex-Mediated (Vasovagal, Situational, or Carotid Sinus Hypersensitivity) Syncope: A Systematic Review for the 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society.

    Science.gov (United States)

    Varosy, Paul D; Chen, Lin Y; Miller, Amy L; Noseworthy, Peter A; Slotwiner, David J; Thiruganasambandamoorthy, Venkatesh

    2017-08-01

    To determine, using systematic review of the biomedical literature, whether pacing reduces risk of recurrent syncope and relevant clinical outcomes among adult patients with reflex-mediated syncope. MEDLINE (through PubMed), EMBASE, and the Cochrane Central Register of Controlled Trials (through October 7, 2015) were searched for randomized trials and observational studies examining pacing and syncope, and the bibliographies of known systematic reviews were also examined. Studies were rejected for poor-quality study methods and for the lack of the population, intervention, comparator, or outcome(s) of interest. Of 3,188 citations reviewed, 10 studies met the inclusion criteria for systematic review, including a total of 676 patients. These included 9 randomized trials and 1 observational study. Of the 10 studies, 4 addressed patients with carotid sinus hypersensitivity, and the remaining 6 addressed vasovagal syncope. Among the 6 open-label (unblinded) studies, we found that pacing was associated with a 70% reduction in recurrent syncope (relative risk [RR]: 0.30; 95% confidence interval [CI]: 0.15-0.60). When the 2 analyzable studies with double-blinded methodology were considered separately, there was no clear benefit (RR: 0.73; 95% CI: 0.25-2.1), but confidence intervals were wide. The strongest evidence was from the randomized, double-blinded ISSUE-3 (Third International Study on Syncope of Uncertain Etiology) trial, which demonstrated a benefit of pacing among patients with recurrent syncope and asystole documented by implantable loop recorder. There are limited data with substantive evidence of outcome ascertainment bias, and only 2 studies with a double-blinded study design have been conducted. The evidence does not support the use of pacing for reflex-mediated syncope beyond patients with recurrent vasovagal syncope and asystole documented by implantable loop recorder. Copyright © 2017 American College of Cardiology Foundation, American Heart Association

  5. Circadian rhythm in Alzheimer disease after trazodone use.

    Science.gov (United States)

    Grippe, Talyta C; Gonçalves, Bruno S B; Louzada, Luciana L; Quintas, Juliana L; Naves, Janeth O S; Camargos, Einstein F; Nóbrega, Otávio T

    2015-01-01

    A circadian rhythm is a cycle of approximately 24 h, responsible for many physiological adjustments, and ageing of the circadian clock contributes to cognitive decline. Rhythmicity is severely impaired in Alzheimer disease (AD) and few therapeutic attempts succeeded in improving sleep disorders in such context. This study evaluated sleep parameters by actigraphy in 30 AD patients before and after trazodone use for 2 weeks, and we show a significant improvement in relative rhythm amplitude (RRA), compatible with a more stable daytime behavioral pattern. So, trazodone appears to produce a stabilization of the circadian rhythms in individuals with AD.

  6. Diurnal rhythm of mitosis in rabbit corneal epithelium.

    Science.gov (United States)

    Fogle, J A; Yoza, B K; Neufeld, A H

    1980-01-01

    Incorporation of 3H-thymidine by rabbit corneal epithelium during the course of a one-hour incubation in vitro varies according to the time of day, suggesting a diurnal rhythm of mitotic activity. Adrenergic decentralization of the cornea does not affect this rhythm. Furthermore, there is no diurnal variation in the basal or sympathomimetically-stimulated cyclic AMP production by freshly excised rabbit corneas, incubated in vitro. Therefore, the diurnal rhythm of corneal epithelial mitotsis in the rabbit is not paced by catecholamines.

  7. Circadian rhythm sleep disorder, free-running type in a sighted male with severe depression, anxiety, and agoraphobia.

    Science.gov (United States)

    Brown, Mark A; Quan, Stuart F; Eichling, Philip S

    2011-02-15

    Circadian rhythm sleep disorder, free-running type (CRSD, FRT) is a disorder in which the intrinsic circadian rhythm is no longer entrained to the 24-hour schedule. A unique case of CRSD, FRT in a 67-year-old sighted male is presented. The patient had a progressively delayed time in bed (TIB) each night, so that he would cycle around the 24-h clock approximately every 30 days. This was meticulously documented each night by the patient over the course of 22 years. The patient's CRSD, FRT was associated with severe depression, anxiety, and agoraphobia. The agoraphobia may have exacerbated the CRSD, FRT. Entrainment and stabilization of his circadian rhythm was accomplished after treatment that included melatonin, light therapy, and increased sleep structure.

  8. Inherited variation in circadian rhythm genes and risks of prostate cancer and three other cancer sites in combined cancer consortia.

    Science.gov (United States)

    Gu, Fangyi; Zhang, Han; Hyland, Paula L; Berndt, Sonja; Gapstur, Susan M; Wheeler, William; Ellipse Consortium, The; Amos, Christopher I; Bezieau, Stephane; Bickeböller, Heike; Brenner, Hermann; Brennan, Paul; Chang-Claude, Jenny; Conti, David V; Doherty, Jennifer Anne; Gruber, Stephen B; Harrison, Tabitha A; Hayes, Richard B; Hoffmeister, Michael; Houlston, Richard S; Hung, Rayjean J; Jenkins, Mark A; Kraft, Peter; Lawrenson, Kate; McKay, James; Markt, Sarah; Mucci, Lorelei; Phelan, Catherine M; Qu, Conghui; Risch, Angela; Rossing, Mary Anne; Wichmann, H-Erich; Shi, Jianxin; Schernhammer, Eva; Yu, Kai; Landi, Maria Teresa; Caporaso, Neil E

    2017-11-01

    Circadian disruption has been linked to carcinogenesis in animal models, but the evidence in humans is inconclusive. Genetic variation in circadian rhythm genes provides a tool to investigate such associations. We examined associations of genetic variation in nine core circadian rhythm genes and six melatonin pathway genes with risk of colorectal, lung, ovarian and prostate cancers using data from the Genetic Associations and Mechanisms in Oncology (GAME-ON) network. The major results for prostate cancer were replicated in the Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial, and for colorectal cancer in the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO). The total number of cancer cases and controls was 15,838/18,159 for colorectal, 14,818/14,227 for prostate, 12,537/17,285 for lung and 4,369/9,123 for ovary. For each cancer site, we conducted gene-based and pathway-based analyses by applying the summary-based Adaptive Rank Truncated Product method (sARTP) on the summary association statistics for each SNP within the candidate gene regions. Aggregate genetic variation in circadian rhythm and melatonin pathways were significantly associated with the risk of prostate cancer in data combining GAME-ON and PLCO, after Bonferroni correction (ppathway  circadian rhythm pathway in GAME-ON (ppathway  = 0.021); this association was not confirmed in GECCO (ppathway  = 0.76) or the combined data (ppathway  = 0.17). No significant association was observed for ovarian and lung cancer. These findings support a potential role for circadian rhythm and melatonin pathways in prostate carcinogenesis. Further functional studies are needed to better understand the underlying biologic mechanisms. © 2017 UICC.

  9. Comparison of QT dispersion during atrial fibrillation and sinus rhythm in the same patients, at normal and prolonged ventricular repolarization

    NARCIS (Netherlands)

    Houltz, B; Darpo, B; Swedberg, K; Blomstrom, P; Crijns, HJGM; Jensen, SM; Svernhage, E; Edvardsson, N

    Aims Drug-induced increase in QT dispersion has been associated with increased risk of ventricular proarrhythmia. The aim of the present study was to compare QT dispersion during atrial fibrillation and sinus rhythm in the same patients at normal and prolonged ventricular repolarization. Methods and

  10. Effect of Circadian Rhythm Disruption and Alcohol on the Oxidative Stress Level in Rat Brain.

    Science.gov (United States)

    Varadinova, Miroslava Georgieva; Valcheva-Traykova, Maria Lozanova; Boyadjieva, Nadka Ivanova

    Alcohol abuse is often associated with disrupted circadian rhythms and sleep, and the link seems to be bidirectional. In addition, it has been shown that exposure to constant illumination may increase lipid peroxidation in tissues. In this study, we investigated the effects of circadian rhythm disruption (CRD) and chronic alcohol intake (A) alone and in combination (CRD+A), on the oxidative stress in total rat brain homogenate. Our results demonstrated that lipid peroxidation was increased in the brain samples of all experimental animals compared with the control ones. The oxidative stress levels increased in the order: Calcohol intake, if accompanied with CRD, might lead to significantly higher lipid peroxidation in the brain, than if present alone. Our data suggest that ethanol metabolites may be involved in the increase of the brain xanthine oxidase activity in rats with chronic alcohol intake.

  11. Circadian rhythms. A protein fold switch joins the circadian oscillator to clock output in cyanobacteria.

    Science.gov (United States)

    Chang, Yong-Gang; Cohen, Susan E; Phong, Connie; Myers, William K; Kim, Yong-Ick; Tseng, Roger; Lin, Jenny; Zhang, Li; Boyd, Joseph S; Lee, Yvonne; Kang, Shannon; Lee, David; Li, Sheng; Britt, R David; Rust, Michael J; Golden, Susan S; LiWang, Andy

    2015-07-17

    Organisms are adapted to the relentless cycles of day and night, because they evolved timekeeping systems called circadian clocks, which regulate biological activities with ~24-hour rhythms. The clock of cyanobacteria is driven by a three-protein oscillator composed of KaiA, KaiB, and KaiC, which together generate a circadian rhythm of KaiC phosphorylation. We show that KaiB flips between two distinct three-dimensional folds, and its rare transition to an active state provides a time delay that is required to match the timing of the oscillator to that of Earth's rotation. Once KaiB switches folds, it binds phosphorylated KaiC and captures KaiA, which initiates a phase transition of the circadian cycle, and it regulates components of the clock-output pathway, which provides the link that joins the timekeeping and signaling functions of the oscillator. Copyright © 2015, American Association for the Advancement of Science.

  12. Circadian rhythms in anesthesia and critical care medicine: potential importance of circadian disruptions.

    Science.gov (United States)

    Brainard, Jason; Gobel, Merit; Bartels, Karsten; Scott, Benjamin; Koeppen, Michael; Eckle, Tobias

    2015-03-01

    The rotation of the earth and associated alternating cycles of light and dark--the basis of our circadian rhythms--are fundamental to human biology and culture. However, it was not until 1971 that researchers first began to describe the molecular mechanisms for the circadian system. During the past few years, groundbreaking research has revealed a multitude of circadian genes affecting a variety of clinical diseases, including diabetes, obesity, sepsis, cardiac ischemia, and sudden cardiac death. Anesthesiologists, in the operating room and intensive care units, manage these diseases on a daily basis as they significantly affect patient outcomes. Intriguingly, sedatives, anesthetics, and the intensive care unit environment have all been shown to disrupt the circadian system in patients. In the current review, we will discuss how newly acquired knowledge of circadian rhythms could lead to changes in clinical practice and new therapeutic concepts. © The Author(s) 2014.

  13. Menstrual changes in sleep, rectal temperature and melatonin rhythms in a subject with premenstrual syndrome.

    Science.gov (United States)

    Shinohara, K; Uchiyama, M; Okawa, M; Saito, K; Kawaguchi, M; Funabashi, T; Kimura, F

    2000-03-10

    We studied a sighted woman with premenstrual syndrome who showed menstrual changes in circadian rhythms. She showed alternative phase shifts in the sleep rhythm in the menstrual cycle: progressive phase advances in the follicular phase and phase delays in the luteal phase. Rectal temperature rhythm also showed similar menstrual changes, but the phase advance and delay started a few days earlier than changes in sleep-wake rhythm so that the two rhythms were dissociated around ovulation and menstruation. These results suggest that her circadian rhythms in sleep and temperature are under the control of ovarian steroid hormones and that these two rhythms have different sensitivity to the hormones.

  14. Cost evaluation of rhythm control methods for atrial fibrillation: evidence from CTAF.

    Science.gov (United States)

    Nattel, Stanley; Lumer, Gerald; Talajic, Mario; Roy, Denis

    2003-09-01

    Atrial fibrillation (AF) is a highly prevalent arrhythmia that is difficult to treat and generates important health care costs. One consideration in the selection of various therapeutic options is the cost of a given treatment compared to that of alternatives. The Canadian Trial of Atrial Fibrillation (CTAF) evaluated the effectiveness of sinus rhythm maintenance with amiodarone compared to propafenone or sotalol in a prospective, randomized fashion. A subsequent CTAF substudy of the medical costs associated with amiodarone vs. propafenone/sotalol found that amiodarone decreased AF-related costs. This paper reviews the results of the CTAF cost-analysis substudy in the context of other analyses in the literature of the cost effectiveness of amiodarone in AF. The costs associated with amiodarone therapy are no greater than for other sinus rhythm maintenance drugs, and for some cost categories and some patient subgroups are likely to be less, despite amiodarone's greater therapeutic efficacy. However, additional considerations are important in evaluating the clinical place of amiodarone, including its adverse effect and pharmacokinetic profile. As well, the results of recent randomized clinical trials have highlighted the limitations of sinus rhythm maintenance as a primary therapeutic objective in AF. The decision about whether and at what point to use amiodarone in a given patient requires a careful analysis of the individual case, in terms of symptomatology during AF, the response to previous treatment regimes, and risk factors for various forms of adverse drug reactions.

  15. Ultradian rhythm unmasked in the Pdf clock mutant of Drosophila.

    Science.gov (United States)

    Seki, Yuuichi; Tanimura, Teiichi

    2014-09-01

    A diverse range of organisms shows physiological and behavioural rhythms with various periods. Extensive studies have been performed to elucidate the molecular mechanisms of circadian rhythms with an approximately 24 h period in both Drosophila and mammals, while less attention has been paid to ultradian rhythms with shorter periods. We used a video-tracking method to monitor the movement of single flies, and clear ultradian rhythms were detected in the locomotor behaviour of wild type and clock mutant flies kept under constant dark conditions. In particular, the Pigment-dispersing factor mutant (Pdf 01) demonstrated a precise and robust ultradian rhythmicity, which was not temperature compensated. Our results suggest that Drosophila has an endogenous ultradian oscillator that is masked by circadian rhythmic behaviours.

  16. Analysis of Nonstationary Time Series for Biological Rhythms Research.

    Science.gov (United States)

    Leise, Tanya L

    2017-06-01

    This article is part of a Journal of Biological Rhythms series exploring analysis and statistics topics relevant to researchers in biological rhythms and sleep research. The goal is to provide an overview of the most common issues that arise in the analysis and interpretation of data in these fields. In this article on time series analysis for biological rhythms, we describe some methods for assessing the rhythmic properties of time series, including tests of whether a time series is indeed rhythmic. Because biological rhythms can exhibit significant fluctuations in their period, phase, and amplitude, their analysis may require methods appropriate for nonstationary time series, such as wavelet transforms, which can measure how these rhythmic parameters change over time. We illustrate these methods using simulated and real time series.

  17. Language familiarity, expectation, and novice musical rhythm production.

    Science.gov (United States)

    Neuhoff, John G; Lidji, Pascale

    2014-12-01

    The music of expert musicians reflects the speech rhythm of their native language. Here, we examine this effect in amateur and novice musicians. English- and French-speaking participants were both instructed to produce simple "English" and "French" tunes using only two keys on a keyboard. All participants later rated the rhythmic variability of English and French speech samples. The rhythmic variability of the "English" and "French" tunes that were produced reflected the perceived rhythmic variability in English and French speech samples. Yet, the pattern was different for English and French participants and did not correspond to the actual measured speech rhythm variability of the speech samples. Surprise recognition tests two weeks later confirmed that the music-speech relationship remained over time. The results show that the relationship between music and speech rhythm is more widespread than previously thought and that musical rhythm production by amateurs and novices is concordant with their rhythmic expectations in the perception of speech.

  18. Guidelines for Genome-Scale Analysis of Biological Rhythms

    NARCIS (Netherlands)

    Hughes, Michael E.; Abruzzi, Katherine C.; Allada, Ravi; Anafi, Ron; Arpat, Alaaddin Bulak; Asher, Gad; Baldi, Pierre; de Bekker, Charissa; Bell-Pedersen, Deborah; Blau, Justin; Brown, Steve; Ceriani, M. Fernanda; Chen, Zheng; Chiu, Joanna C.; Cox, Juergen; Crowell, Alexander M.; Debruyne, Jason P.; Dijk, Derk-Jan; DiTacchio, Luciano; Doyle, Francis J.; Duffield, Giles E.; Dunlap, Jay C.; Eckel-Mahan, Kristin; Esser, Karyn A.; FitzGerald, Garret A.; Forger, Daniel B.; Francey, Lauren J.; Fu, Ying-Hui; Gachon, Frédéric; Gatfield, David; de Goede, Paul; Golden, Susan S.; Green, Carla; Harer, John; Harmer, Stacey; Haspel, Jeff; Hastings, Michael H.; Herzel, Hanspeter; Herzog, Erik D.; Hoffmann, Christy; Hong, Christian; Hughey, Jacob J.; Hurley, Jennifer M.; de la Iglesia, Horacio O.; Johnson, Carl; Kay, Steve A.; Koike, Nobuya; Kornacker, Karl; Kramer, Achim; Lamia, Katja; Leise, Tanya; Lewis, Scott A.; Li, Jiajia; Li, Xiaodong; Liu, Andrew C.; Loros, Jennifer J.; Martino, Tami A.; Menet, Jerome S.; Merrow, Martha; Millar, Andrew J.; Mockler, Todd; Naef, Felix; Nagoshi, Emi; Nitabach, Michael N.; Olmedo, Maria; Nusinow, Dmitri A.; Ptáček, Louis J.; Rand, David; Reddy, Akhilesh B.; Robles, Maria S.; Roenneberg, Till; Rosbash, Michael; Ruben, Marc D.; Rund, Samuel S. C.; Sancar, Aziz; Sassone-Corsi, Paolo; Sehgal, Amita; Sherrill-Mix, Scott; Skene, Debra J.; Storch, Kai-Florian; Takahashi, Joseph S.; Ueda, Hiroki R.; Wang, Han; Weitz, Charles; Westermark, Pål O.; Wijnen, Herman; Xu, Ying; Wu, Gang; Yoo, Seung-Hee; Young, Michael; Zhang, Eric Erquan; Zielinski, Tomasz; Hogenesch, John B.

    2017-01-01

    Genome biology approaches have made enormous contributions to our understanding of biological rhythms, particularly in identifying outputs of the clock, including RNAs, proteins, and metabolites, whose abundance oscillates throughout the day. These methods hold significant promise for future

  19. Capturing daily urban rhythms: the use of location aware technologies

    CSIR Research Space (South Africa)

    Krygsman, S

    2007-07-01

    Full Text Available on Computers in Urban Planning and Urban Management 11-13 July, 2007 Capturing daily urban rhythms: The use of location aware technologies Dr. Stephan Krygsman, Department of Logistics, University of Stellenbosch, South Africa, skrygsman...

  20. Melatonin in sleepless children : everything has a rhythm?

    NARCIS (Netherlands)

    van Geijlswijk, I.M.|info:eu-repo/dai/nl/413489477

    2011-01-01

    Every living organism has an biological clock regulating endogenous melatonin production, synchronized by exogenous impulses like daylight, temperature and feeding. Inappropriately applied bright light disturbs this melatonin rhythm. Some large swine producers apply artificial light three times a

  1. Dual γ rhythm generators control interlaminar synchrony in auditory cortex

    National Research Council Canada - National Science Library

    Ainsworth, Matthew; Lee, Shane; Cunningham, Mark O; Roopun, Anita K; Traub, Roger D; Kopell, Nancy J; Whittington, Miles A

    2011-01-01

    .... Here we show that, for inhibition-based gamma rhythms in vitro in rat neocortical slices, mechanistically distinct local circuit generators exist in different laminae of rat primary auditory cortex...

  2. Commentary: Circadian rhythm in the pink–orange bread mould ...

    Indian Academy of Sciences (India)

    2007-07-27

    Jul 27, 2007 ... Home; Journals; Journal of Biosciences; Volume 32; Issue 6. Commentary: Circadian rhythm in the pink–orange bread mould Neurospora crassa: for what? Ramesh Maheshwari. Volume 32 Issue 6 September 2007 pp 1053-1058 ...

  3. Reversal of theta rhythm flow through intact hippocampal circuits.

    Science.gov (United States)

    Jackson, Jesse; Amilhon, Bénédicte; Goutagny, Romain; Bott, Jean-Bastien; Manseau, Frédéric; Kortleven, Christian; Bressler, Steven L; Williams, Sylvain

    2014-10-01

    Activity flow through the hippocampus is thought to arise exclusively from unidirectional excitatory synaptic signaling from CA3 to CA1 to the subiculum. Theta rhythms are important for hippocampal synchronization during episodic memory processing; thus, it is assumed that theta rhythms follow these excitatory feedforward circuits. To the contrary, we found that theta rhythms generated in the rat subiculum flowed backward to actively modulate spike timing and local network rhythms in CA1 and CA3. This reversed signaling involved GABAergic mechanisms. However, when hippocampal circuits were physically limited to a lamellar slab, CA3 outputs synchronized CA1 and the subiculum using excitatory mechanisms, as predicted by classic hippocampal models. Finally, analysis of in vivo recordings revealed that this reversed theta flow was most prominent during REM sleep. These data demonstrate that communication between CA3, CA1 and the subiculum is not exclusively unidirectional or excitatory and that reversed inhibitory theta signaling also contributes to intrahippocampal synchrony.

  4. Frailty syndrome in patients with heart rhythm disorders.

    Science.gov (United States)

    Mlynarska, Agnieszka; Mlynarski, Rafal; Golba, Krzysztof S

    2017-09-01

    To assess the prevalence of frailty syndrome in patients with heart rhythm disorders that qualified for pacemaker implantation. The study included 171 patients (83 women, aged 73.9 ± 6.7 years) who qualified for pacemaker implantation as a result of sinus node dysfunction (81 patients) or atrio-ventricular blocks (AVB; 90 patients). A total of 60 patients (25 women, aged 72.40 ± 7.09 years) without heart rhythm disorders were included in the control group. Frailty syndrome was diagnosed using the Canadian Study of Health and Aging Clinical Frailty Scale test. Frailty syndrome was diagnosed in 25.15% of the patients, and pre-frailty in 36.84% of the patients. Frailty syndrome was diagnosed in 10% of the control group, and the average value of frailty was 3.35 ± 0.92. Frailty occurred significantly more often among patients with AVB (33.34%) compared with patients who were diagnosed with sinus node dysfunction (16.05%); P = 0.0081. The average score of frailty for sinus node dysfunction was 3.71 ± 0.89, and for AVB it was 4.14 ± 0.93; P = 0.0152. In the case of AVB, the women had a statistically more intense level of frailty of 4.54 ± 0.90 as compared with the men 3.87 ± 0.85; P = 0.0294. In the multiple logistic analysis, the presence of any arrhythmia was strongly associated with frailty syndrome (OR 2.1286, 95% CI 1.4594 - 3.1049; P = 0.0001). Frailty syndrome was diagnosed in one-quarter of patients with cardiac arrhythmias, whereas a further 40% were at a higher risk of frailty syndrome, and its occurrence was significantly higher if compared with the control group. Frailty occurred significantly more often among patients with atrio-ventricular blocks, especially in women. The results of the present research showed that there is a statistical association between frailty and arrhythmias. Geriatr Gerontol Int 2017; 17: 1313-1318. © 2016 Japan Geriatrics Society.

  5. Affective Disruption from Social Rhythm and Behavioral Approach System (BAS) Sensitivities: A Test of the Integration of the Social Zeitgeber and BAS Theories of Bipolar Disorder.

    Science.gov (United States)

    Boland, Elaine M; Stange, Jonathan P; Labelle, Denise R; Shapero, Benjamin G; Weiss, Rachel B; Abramson, Lyn Y; Alloy, Lauren B

    2016-05-01

    The Behavioral Approach System (BAS)/Reward Hypersensitivity Theory and the Social Zeitgeber Theory are two biopsychosocial theories of bipolar spectrum disorders (BSD) that may work together to explain affective dysregulation. The present study examined whether BAS sensitivity is associated with affective symptoms via a) increased social rhythm disruption in response to BAS-relevant life events, or b) greater exposure to BAS events leading to social rhythm disruption and subsequent symptoms. Results indicated that high BAS individuals were more likely to experience social rhythm disruption following BAS-relevant events. Social rhythm disruption mediated the association between BAS-relevant events and symptoms (hypothesis a). High BAS individuals experienced significantly more BAS-relevant events, which predicted greater social rhythm disruption, which predicted greater levels of affective symptoms (hypothesis b). Individuals at risk for BSD may be sensitive to BAS-relevant stimuli, experience more BAS-relevant events, and experience affective dysregulation due to the interplay of the BAS and circadian rhythms.

  6. Another place, another timer: Marine species and the rhythms of life

    OpenAIRE

    Tessmar-Raible, Kristin; Raible, Florian; Arboleda, Enrique

    2011-01-01

    The marine ecosystem is governed by a multitude of environmental cycles, all of which are linked to the periodical recurrence of the sun or the moon. In accordance with these cycles, marine species exhibit a variety of biological rhythms, ranging from circadian and circatidal rhythms to circalunar and seasonal rhythms. However, our current molecular understanding of biological rhythms and clocks is largely restricted to solar-controlled circadian and seasonal rhythms in land model species. He...

  7. Physiology and regulation of biological rhythms in laboratory animals : an overview

    OpenAIRE

    Wollnik, Franziska

    1989-01-01

    Biological rhythms have been observed in practically all groups of laboratory mammals and at every level of physiological and behavioural organization. Biological rhythms are classified according to their period as ultradian (24 h), and seasonal or circannual rhythms (~1 year). This review outlines what is known about the neurobiology of biological rhythms in mammals and describes the hierarchical order in which ultradian, circadian and infradian rhythms are related to each other. The article...

  8. Temporal expectancies driven by self- and externally generated rhythms.

    Science.gov (United States)

    Jones, Alexander; Hsu, Yi-Fang; Granjon, Lionel; Waszak, Florian

    2017-08-01

    The dynamic attending theory proposes that rhythms entrain periodic fluctuations of attention which modulate the gain of sensory input. However, temporal expectancies can also be driven by the mere passage of time (foreperiod effect). It is currently unknown how these two types of temporal expectancy relate to each other, i.e. whether they work in parallel and have distinguishable neural signatures. The current research addresses this issue. Participants either tapped a 1Hz rhythm (active task) or were passively presented with the same rhythm using tactile stimulators (passive task). Based on this rhythm an auditory target was then presented early, in synchrony, or late. Behavioural results were in line with the dynamic attending theory as RTs were faster for in- compared to out-of-synchrony targets. Electrophysiological results suggested self-generated and externally induced rhythms to entrain neural oscillations in the delta frequency band. Auditory ERPs showed evidence of two distinct temporal expectancy processes. Both tasks demonstrated a pattern which followed a linear foreperiod effect. In the active task, however, we also observed an ERP effect consistent with the dynamic attending theory. This study shows that temporal expectancies generated by a rhythm and expectancy generated by the mere passage of time can work in parallel and sheds light on how these mechanisms are implemented in the brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Dynamical Analysis of bantam-Regulated Drosophila Circadian Rhythm Model

    Science.gov (United States)

    Li, Ying; Liu, Zengrong

    MicroRNAs (miRNAs) interact with 3‧untranslated region (UTR) elements of target genes to regulate mRNA stability or translation, and play a crucial role in regulating many different biological processes. bantam, a conserved miRNA, is involved in several functions, such as regulating Drosophila growth and circadian rhythm. Recently, it has been discovered that bantam plays a crucial role in the core circadian pacemaker. In this paper, based on experimental observations, a detailed dynamical model of bantam-regulated circadian clock system is developed to show the post-transcriptional behaviors in the modulation of Drosophila circadian rhythm, in which the regulation of bantam is incorporated into a classical model. The dynamical behaviors of the model are consistent with the experimental observations, which shows that bantam is an important regulator of Drosophila circadian rhythm. The sensitivity analysis of parameters demonstrates that with the regulation of bantam the system is more sensitive to perturbations, indicating that bantam regulation makes it easier for the organism to modulate its period against the environmental perturbations. The effectiveness in rescuing locomotor activity rhythms of mutated flies shows that bantam is necessary for strong and sustained rhythms. In addition, the biological mechanisms of bantam regulation are analyzed, which may help us more clearly understand Drosophila circadian rhythm regulated by other miRNAs.

  10. Neural mechanisms of rhythm perception: current findings and future perspectives.

    Science.gov (United States)

    Grahn, Jessica A

    2012-10-01

    Perception of temporal patterns is fundamental to normal hearing, speech, motor control, and music. Certain types of pattern understanding are unique to humans, such as musical rhythm. Although human responses to musical rhythm are universal, there is much we do not understand about how rhythm is processed in the brain. Here, I consider findings from research into basic timing mechanisms and models through to the neuroscience of rhythm and meter. A network of neural areas, including motor regions, is regularly implicated in basic timing as well as processing of musical rhythm. However, fractionating the specific roles of individual areas in this network has remained a challenge. Distinctions in activity patterns appear between "automatic" and "cognitively controlled" timing processes, but the perception of musical rhythm requires features of both automatic and controlled processes. In addition, many experimental manipulations rely on participants directing their attention toward or away from certain stimulus features, and measuring corresponding differences in neural activity. Many temporal features, however, are implicitly processed whether attended to or not, making it difficult to create controlled baseline conditions for experimental comparisons. The variety of stimuli, paradigms, and definitions can further complicate comparisons across domains or methodologies. Despite these challenges, the high level of interest and multitude of methodological approaches from different cognitive domains (including music, language, and motor learning) have yielded new insights and hold promise for future progress. Copyright © 2012 Cognitive Science Society, Inc.

  11. Circadian rhythms of hedonic drinking behavior in mice.

    Science.gov (United States)

    Bainier, Claire; Mateo, Maria; Felder-Schmittbuhl, Marie-Paule; Mendoza, Jorge

    2017-05-04

    In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus is the site of the main circadian clock, synchronized by the light-dark cycle, which generates behavioral rhythms like feeding, drinking and activity. Notwithstanding, the main role of the SCN clock on the control of all circadian rhythms has been questioned due to the presence of clock activity in many brain areas, including those implicated in the regulation of feeding and reward. Moreover, whether circadian rhythms of particular motivated behaviors exist is unknown. Here, we evaluated the spontaneous daily and circadian behavior of consumption of a sweet caloric solution (5-10% sucrose), and the effects of sucrose intake on the expression of clock genes in the mouse brain. Mice showed a daily (in a light-dark cycle) and a circadian (in constant darkness conditions) rhythm in the intake and sucrose preference with a rise for both parameters at night (or subjective night). In addition, we observed changes in the circadian day-night expression of the clock gene Per2 in the SCN, cortex and striatum of animals ingesting sucrose compared to control mice on pure water. Finally, daily rhythms of sucrose intake and preference were abolished in Per2 Brdm1 - and double Per1 -/- Per2 Brdm1 -mutant animals. These data indicate that the expression of circadian rhythms of hedonic feeding behaviors may be controlled by brain circadian clocks and Per gene expression. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. The phonetic rhythm/syntax headedness connection: Evidence from Tagalog

    Science.gov (United States)

    Bird, Sonya; Fais, Laurel; Werker, Janet

    2005-04-01

    Ramus, Nespor, and Mehler [Cognition (1999)] show that the rhythm of a language (broadly: stress- versus syllable- versus mora-timing) results from the proportion of vocalic material in an utterance (%V) and the standard deviation of consonantal intervals (delta-C). Based on 14 languages, Shukla, Nespor, and Mehler [submitted] further argue that rhythm is correlated with syntactic headedness: low %V is correlated with head-first languages (e.g., English); high %V is correlated with head-final languages (e.g., Japanese). Together, these proposals have important implications for language acquisition: infants can discriminate across rhythm classes [Nazzi, Bertoncini, and Mehler, J. Exp. Psych: Human Perception and Performance (1998)]. If rhythm, as defined by %V and delta-C, can predict headedness, then infants can potentially use rhythm information to bootstrap into their languages syntactic structure. This paper reports on a study analyzing rhythm in a language not yet considered: Tagalog. Results support the Shukla et al. proposal in an interesting way: based on its %V and delta-C, Tagalog falls between head-first and head-last languages, slighty closer to the head-first group. This placement correlates well with the fact that, although Tagalog is said to be primarily head-first syntactically, head-last phrases are permitted and common in the language.

  13. Circadian rhythms in cognitive performance: implications for neuropsychological assessment

    Directory of Open Access Journals (Sweden)

    Valdez P

    2012-12-01

    Full Text Available Pablo Valdez, Candelaria Ramírez, Aída GarcíaLaboratory of Psychophysiology, School of Psychology, University of Nuevo León, Monterrey, Nuevo León, MéxicoAbstract: Circadian variations have been found in human performance, including the efficiency to execute many tasks, such as sensory, motor, reaction time, time estimation, memory, verbal, arithmetic calculations, and simulated driving tasks. Performance increases during the day and decreases during the night. Circadian rhythms have been found in three basic neuropsychological processes (attention, working memory, and executive functions, which may explain oscillations in the performance of many tasks. The time course of circadian rhythms in cognitive performance may be modified significantly in patients with brain disorders, due to chronotype, age, alterations of the circadian rhythm, sleep deprivation, type of disorder, and medication. This review analyzes the recent results on circadian rhythms in cognitive performance, as well as the implications of these rhythms for the neuropsychological assessment of patients with brain disorders such as traumatic head injury, stroke, dementia, developmental disorders, and psychiatric disorders.Keywords: human circadian rhythms, cognitive performance, neuropsychological assessment, attention, working memory, executive functions

  14. Educating the sense of rhythm in primary education students

    Directory of Open Access Journals (Sweden)

    Silvia GRĂDINARU

    2017-03-01

    Full Text Available Background: Rhythm as a core element of complex coordination is the key to efficient moulding of motor skills specific to sports activities in curricula. Practicing physical exercise in a varied rhythm and tempo in primary school students moulds the skill of achieving correct movement basics (direction, span, coordination, and expressivity. The use of music in sports classes improves kinetics and vestibular sensitivity. The sense of rhythm and tempo are imperative criteria in vocational schools. Purpose: This paper aims to describe a pattern of means selected to develop the sense of rhythm and to allow movements in different sports branches with increased efficiency. Methods: The test battery was applied on a sample of 15 students from the 4th grade of the “Ion Vidu” National Arts College in Timisoara, Romania, aged 9-10 years, over an entire school year, using different rhythms and tempos during sports classes, which were later used in gymnastics, athletic events, and basketball. Results: Data recorded after the application tests, processed and interpreted confirms the proposed assumption and validates the motor contents used. Conclusions: Sense of rhythm is a component of coordinative capacity that is required to be educated from an early age. Rhythmic movements are easier to automate saving energy and motivating students to an active and conscious participation.

  15. Circadian rhythms and depression: human psychopathology and animal models.

    Science.gov (United States)

    Kronfeld-Schor, Noga; Einat, Haim

    2012-01-01

    Most organisms (including humans) developed daily rhythms in almost every aspect of their body. It is not surprising that rhythms are also related to affect in health and disease. In the present review we present data that demonstrate the evidence for significant interactions between circadian rhythms and affect from both human studies and animal models research. A number of lines of evidence obtained from human and from animal models research clearly demonstrate relationships between depression and circadian rhythms including (1) daily patterns of depression; (2) seasonal affective disorder; (3) connections between circadian clock genes and depression; (4) relationship between sleep disorders and depression; (5) the antidepressant effect of sleep deprivation; (6) the antidepressant effect of bright light exposure; and (7) the effects of antidepressant drugs on sleep and circadian rhythms. The integration of data suggests that the relationships between the circadian system and depression are well established but the underlying biology of the interactions is far from being understood. We suggest that an important factor hindering research into the underlying mechanisms is the lack of good animal models and we propose that additional efforts in that area should be made. One step in that direction could be the attempt to develop models utilizing diurnal animals which might have a better homology to humans with regard to their circadian rhythms. This article is part of a Special Issue entitled 'Anxiety and Depression'. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Variabilidad de la frecuencia cardiaca y alteraciones del ritmo cardiaco asociados a la terapia con células progenitoras en enfermedad cardiovascular Heart rate variability and cardiac rhythm alterations associated with stem cell therapy in cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Carlos M Orrego

    2007-12-01

    events as direct consequence of autonomous nervous system dysfunction. Methods: patients that received autologous transplant derived from bone marrow and that had acute or chronic ischemic heart disease with ejection fraction less than 45% susceptible or not of surgical revascularization and with zones of necrotic and viable myocardial tissue, were analyzed. 24 hours Holter monitoring before transplant and at two, six and twelve months after the intervention was performed. Results: data of 16 patients regarding maximal, minimal and mean heart rate average, variability of heart rate and appearance of malign ventricular arrhythmias were analyzed. Therapy with stem cells derived from bone marrow was associated with a statistically significant improvement of heart rate variability (SDNN going from 65.44 ± 27 ms. to 102.12 ± 37.88 ms. (p=0.004 and 100.23 ± 42.88 ms. (p=0.013 at 2 and 6 months respectively. With regard to the cardiovascular risk classification according to the variability of heart rate (SDNN, all patients considered at high risk (SDNN <50ms. before the procedure, turned to intermediate or low risk in the six months follow-up. Besides, no greater risk of developing malign ventricular arrhythmias was found during the follow-up after therapy with stem cells derived from bone marrow. Conclusion: in patients with ischemic cardiopathy under autologous bone marrow transplant for myocardial regeneration, variability of heart rate measured by SDNN increases significantly, carrying with it a decrease in cardiovascular risk. Furthermore, risk of increased ventricular arrhythmias was not found.

  17. Angiotensin receptor blocker as adjunctive therapy for rhythm control in atrial fibrillation: results of the irbesartan-amiodarone trial.

    Science.gov (United States)

    Madrid, Antonio H; Escobar, Carlos; Rebollo, José María G; Marín, Irene; Bernal, Enrique; Nannini, Sebastián; Limón, Lilianna; Peng, Jian; Moro, Concepción

    2003-09-01

    Atrial fibrillation (AF) is a common arrhythmia associated with increased risk of stroke and mortality. The early appearance of electrical remodeling is followed by structural remodeling of the atrial tissue. Direct current cardioversion of persistent AF is the most effective treatment for the restoration of sinus rhythm, but it is hampered by a high percentage of recurrences. Recurrences may be the consequence of both electrical and structural remodeling. A study on the use of irbesartan to maintain sinus rhythm in patients with long-lasting persistent AF showed that this angiotensin II receptor blocker combined with amiodarone prolonged sinus rhythm after cardioversion. Irbesartan may have antifibrotic effects due not only to the ability to diminish the synthesis of collagen type I molecules but also to its capacity to stimulate the degradation of collagen type I fibers, as has been demonstrated with losartan, another angiotensin II receptor blocker. This suggests that efforts to reduce the structural changes that occur during AF may be more useful in preventing recurrences than efforts designed to minimize the electrical changes alone. The AFFIRM trial compared two approaches to the treatment of AF: cardioversion with antiarrhythmic drugs to maintain sinus rhythm and the use of rate-controlling drugs. The results show that management of AF with the rhythm-control strategy offers no survival advantage over the rate-control strategy. However, non-antiarrhythmic drugs to prevent recurrences, like irbesartan, were not controlled and amiodarone was used in a low percentage of the patients. The treatment strategies proposed in both AFFIRM and RACE, in our opinion, may not be the optimal. The modern clinical approach to AF involves an early intervention to restore sinus rhythm, therefore preventing atrial remodeling. The pretreatment of patients with AF who undergo electrical cardioversion is very important and will be the subject for continuous improvement.

  18. Speech rhythm alterations in Spanish-speaking individuals with Alzheimer's disease.

    Science.gov (United States)

    Martínez-Sánchez, Francisco; Meilán, Juan J G; Vera-Ferrandiz, Juan Antonio; Carro, Juan; Pujante-Valverde, Isabel M; Ivanova, Olga; Carcavilla, Nuria

    2017-07-01

    Rhythm is the speech property related to the temporal organization of sounds. Considerable evidence is now available for suggesting that dementia of Alzheimer's type is associated with impairments in speech rhythm. The aim of this study is to assess the use of an automatic computerized system for measuring speech rhythm characteristics in an oral reading task performed by 45 patients with Alzheimer's disease (AD) compared with those same characteristics among 82 healthy older adults without a diagnosis of dementia, and matched by age, sex and cultural background. Ranges of rhythmic-metric and clinical measurements were applied. The results show rhythmic differences between the groups, with higher variability of syllabic intervals in AD patients. Signal processing algorithms applied to oral reading recordings prove to be capable of differentiating between AD patients and older adults without dementia with an accuracy of 87% (specificity 81.7%, sensitivity 82.2%), based on the standard deviation of the duration of syllabic intervals. Experimental results show that the syllabic variability measurements extracted from the speech signal can be used to distinguish between older adults without a diagnosis of dementia and those with AD, and may be useful as a tool for the objective study and quantification of speech deficits in AD.

  19. Canadian Cardiovascular Society atrial fibrillation guidelines 2010: rate and rhythm management.

    Science.gov (United States)

    Gillis, Anne M; Verma, Atul; Talajic, Mario; Nattel, Stanley; Dorian, Paul

    2011-01-01

    The goals of atrial fibrillation (AF) and atrial flutter (AFL) arrhythmia management are to alleviate patient symptoms, improve patient quality of life, and minimize the morbidity associated with AF and AFL. Arrhythmia management usually commences with drugs to slow the ventricular rate. The addition of class I or class III antiarrhythmic drugs for restoration or maintenance of sinus rhythm is largely determined by patient symptoms and preferences. For rate control, treatment of persistent or permanent AF and AFL should aim for a resting heart rate of myocardial infarction or left ventricular dysfunction. Digoxin is not recommended as monotherapy for rate control in active patients. Digoxin and dronedarone may be used in combination with other agents to optimize rate control. The first-choice antiarrhythmic drug for maintenance of sinus rhythm in patients with non structural heart disease can be any one of dronedarone, flecainide, propafenone, or sotalol. In patients with abnormal ventricular function but left ventricular ejection fraction >35%, dronedarone, sotalol, or amiodarone is recommended. In patients with left ventricular ejection fraction <35%, amiodarone is the only drug usually recommended. Intermittent antiarrhythmic drug therapy ("pill in the pocket") may be considered in symptomatic patients with infrequent, longer-lasting episodes of AF or AFL as an alternative to daily antiarrhythmic therapy. Referral for ablation of AF may be considered for patients who remain symptomatic after adequate trials of antiarrhythmic drug therapy and in whom a rhythm control strategy remains desired. Copyright © 2011 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  20. Classification of Hand Grasp Kinetics and Types Using Movement-Related Cortical Potentials and EEG Rhythms

    Directory of Open Access Journals (Sweden)

    Mads Jochumsen

    2017-01-01

    Full Text Available Detection of single-trial movement intentions from EEG is paramount for brain-computer interfacing in neurorehabilitation. These movement intentions contain task-related information and if this is decoded, the neurorehabilitation could potentially be optimized. The aim of this study was to classify single-trial movement intentions associated with two levels of force and speed and three different grasp types using EEG rhythms and components of the movement-related cortical potential (MRCP as features. The feature importance was used to estimate encoding of discriminative information. Two data sets were used. 29 healthy subjects executed and imagined different hand movements, while EEG was recorded over the contralateral sensorimotor cortex. The following features were extracted: delta, theta, mu/alpha, beta, and gamma rhythms, readiness potential, negative slope, and motor potential of the MRCP. Sequential forward selection was performed, and classification was performed using linear discriminant analysis and support vector machines. Limited classification accuracies were obtained from the EEG rhythms and MRCP-components: 0.48±0.05 (grasp types, 0.41±0.07 (kinetic profiles, motor execution, and 0.39±0.08 (kinetic profiles, motor imagination. Delta activity contributed the most but all features provided discriminative information. These findings suggest that information from the entire EEG spectrum is needed to discriminate between task-related parameters from single-trial movement intentions.

  1. Changes in the diurnal rhythms during a 45-day head-down bed rest.

    Directory of Open Access Journals (Sweden)

    Xiaodi Liang

    Full Text Available In spaceflight human circadian rhythms and sleep patterns are likely subject to change, which consequently disturbs human physiology, cognitive abilities and performance efficiency. However, the influence of microgravity on sleep and circadian clock as well as the underlying mechanisms remain largely unknown. Placing volunteers in a prone position, whereby their heads rest at an angle of -6° below horizontal, mimics the microgravity environment in orbital flight. Such positioning is termed head-down bed rest (HDBR. In this work, we analysed the influence of a 45-day HDBR on physiological diurnal rhythms. We examined urinary electrolyte and hormone excretion, and the results show a dramatic elevation of cortisol levels during HDBR and recovery. Increased diuresis, melatonin and testosterone were observed at certain periods during HDBR. In addition, we investigated the changes in urination and defecation frequencies and found that the rhythmicity of urinary frequency during lights-off during and after HDBR was higher than control. The grouped defecation frequency data exhibits rhythmicity before and during HDBR but not after HDBR. Together, these data demonstrate that HDBR can alter a number of physiological processes associated with diurnal rhythms.

  2. Effects of Lithium and 2,4-Dichlorophenol on Zebrafish: Circadian Rhythm Disorder and Molecular Effects.

    Science.gov (United States)

    Xiao, Bo; Cui, Li-Qiang; Ding, Cheng; Wang, Han

    2017-06-01

    The aim of this study was to investigate lithium and 2,4-dichlorophenol (2,4-DCP)-induced circadian rhythm disorder and their genome-wide effects in zebrafish. Zebrafish larvae were exposed to 250 ppm LiCl (n = 40) or 20 ppm 2,4-DCP. RNA was subsequently extracted and determined quantitatively. The mRNA levels of circadian clock-related genes, including clock1a, bmal1b, per2, and per1b, were determined. Microarray datasets were generated and the differentially expressed genes (DEGs) were identified. The mRNA levels of some upregulated and downregulated DEGs were examined by quantitative real-time polymerase chain reaction (RT-PCR). Finally, gene ontology (GO) enrichment analysis was applied to determine the roles of the DEGs. The mRNA expression levels of circadian rhythm-related genes in the daily cycle were significantly affected after incubation of zebrafish with LiCl and 2,4-DCP. Many genes were differentially expressed during the light phase (97 h) and RT-PCR validation tests revealed that the expression patterns of DEGs were in accordance with those obtained by microarray analysis. GO functional enrichment analysis showed that the DEGs in LiCl- and 2,4-DCP-treated groups were associated with signal transduction and development. Collectively, our findings indicate that LiCl and 2,4-DCP could affect signal transduction pathways and immune response, thereby inducing circadian rhythm disorder.

  3. Aging differentially affects alpha and beta sensorimotor rhythms in a go/nogo task.

    Science.gov (United States)

    Schmiedt-Fehr, Christina; Mathes, Birgit; Kedilaya, Shwetha; Krauss, Janna; Basar-Eroglu, Canan

    2016-10-01

    This study compared sensorimotor alpha and beta brain oscillations in young and older adults, to examine their functional distinctness and susceptibility to aging. Electroencephalographic data were compared between young (age 23±3) and older adults (age 64±7) in terms of event-related spectral perturbation in alpha and beta bands during a go/nogo task. Age selectively influenced beta rhythms, with younger compared to older adults showing, first, less attenuation during movement preparation and execution, and, second, a greater rebound after movement end. Alpha rhythms differed after response inhibition, with an additional alpha rebound occurring in older, but not younger adults. The results indicate neural over-recruitment in healthy aging, which appears most likely linked to alterations in multiple factors associated with sensory and cognitive aspects of motor control, and which does not consistently or directly impact response speed. The results imply that sensorimotor alpha and beta rhythms may reflect different neural trajectories in aging. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  4. The development and course of bipolar spectrum disorders: an integrated reward and circadian rhythm dysregulation model.

    Science.gov (United States)

    Alloy, Lauren B; Nusslock, Robin; Boland, Elaine M

    2015-01-01

    In this article, we present and review the evidence for two major biopsychosocial theories of the onset and course of bipolar spectrum disorders (BSDs) that integrate behavioral, environmental, and neurobiological mechanisms: the reward hypersensitivity and the social/circadian rhythm disruption models. We describe the clinical features, spectrum, age of onset, and course of BSDs. We then discuss research designs relevant to demonstrating whether a hypothesized mechanism represents a correlate, vulnerability, or predictor of the course of BSDs, as well as important methodological issues. We next present the reward hypersensitivity model of BSD, followed by the social/circadian rhythm disruption model of BSD. For each model, we review evidence regarding whether the proposed underlying mechanism is associated with BSDs, provides vulnerability to the onset of BSDs, and predicts the course of BSDs. We then present a new integrated reward/circadian rhythm (RCR) dysregulation model of BSD and discuss how the RCR model explains the symptoms, onset, and course of BSDs. We end with recommendations for future research directions.

  5. Development of the posterior basic rhythm in children with autism.

    Science.gov (United States)

    Takagaki, Kentaroh; Russell, Jean; Lippert, Michael T; Motamedi, Gholam K

    2015-02-01

    Early detection of autism is critical for effective intervention, but currently, no simple screening tests are available. Furthermore, little is known about the development of brain dynamics in young children. We examine the early neurophysiological manifestations of autism by retrospectively analyzing EEG. In particular, we focus on maturation of the posterior basic rhythm (PBR), which is one of the most characteristic features of the normal EEG, and comprises a discrete functional state. Subjects with a diagnosis of autism (n=74), as well as normal (n=134) and epileptic (n=108) controls, were extracted retrospectively from our digital EEG database. Segments with clear PBR were extracted, and standard signal analysis methods were used to calculate peak PBR frequency, power, and coherence. In our cohort, a subset of autistic children show accelerated development of the PBR, with early maturation especially in the 2- to 4-year old range. The overall coherence of PBR-specific activity is also lower in autistic children in our cohort. These findings provide evidence that autism is associated with accelerated development of the PBR. These findings generate a clinical hypothesis for future prospective studies on the efficacy of these simple measures as a diagnostic or screening tool. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Activity rhythm degrades after strenuous exercise in chronic fatigue syndrome.

    Science.gov (United States)

    Ohashi, Kyoko; Yamamoto, Yoshiharu; Natelson, Benjamin H

    2002-09-01

    Post-exertional exacerbation of symptoms is one of the major characteristics of chronic fatigue syndrome (CFS). In this study, we evaluated the hypothesis that disturbances in circadian chronobiological regulation may play a role in generating this phenomenon. We recorded physical activity for 6-day periods in 16 women (10 CFS and 6 sedentary healthy controls, CON) before and after performing a maximal treadmill test. We calculated activity rhythms by computing autocorrelation coefficients by cutting 1 day apart from the data as a template and sliding it sequentially through each of the other days; all of 6 days were used as the templates. The peak value of autocorrelation coefficient (R) and the time between peak R's (circadian period, CP) were calculated. CFS patients had a lengthening (P < .05) of mean circadian period (MCP) that was longer than 24 h (P < .05), while MCP in CON remained unchanged. No difference was found in the standard error of each subject's MCP (circadian period variability, CPV) before and after exercise for both groups. We interpret this increase in circadian rest-activity period seen in CFS patients following exercise to indicate that exhaustive exercise interferes with normal entrainment to 24-h zeitgeber(s). This effect may be associated in part with the common patient complaint of symptom worsening following exertion. Copyright 2002 Elsevier Science Inc.

  7. Gravity and thermoregulation: metabolic changes and circadian rhythms

    Science.gov (United States)

    Robinson, E. L.; Fuller, C. A.

    2000-01-01

    Gravity appears to alter thermoregulation through changes in both the regulated level of body temperature and the rhythmic organization of temperature regulation. Gravity has been hypothesized to have an associated metabolic cost. Increased resting energy expenditure and dietary intake have been observed in animals during centrifuge experiments at hypergravity. Thus far, only animals have shown a corresponding reduction in metabolism in microgravity. Altered heat loss has been proposed as a response to altered gravitational environments, but remains documented only as changes in skin temperature. Changes in circadian timing, including the body temperature rhythm, have been shown in both hypergravity and microgravity, and probably contribute to alterations in sleep and performance. Changes in body temperature regulation may result from circadian disturbance, from the direct or indirect actions of gravity on the regulated temperature, or from changes in thermoregulatory effectors (heat production and heat loss) due to altered gravitational load and convective changes. To date, however, we have little data on the underlying thermoregulatory changes in altered gravity, and thus the precise mechanisms by which gravity alters temperature regulation remain largely unknown.

  8. Variation in nocturnality and circadian activity rhythms between photoresponsive F344 and nonphotoresponsive Sprague Dawley rats

    Directory of Open Access Journals (Sweden)

    Johnson Cynthia E

    2008-09-01

    Full Text Available Abstract Background Variation in circadian rhythms and nocturnality may, hypothetically, be related to or independent of genetic variation in photoperiodic mediation of seasonal changes in physiology and behavior. We hypothesized that strain variation in photoperiodism between photoperiodic F344 rats and nonphotoperiodic Harlan Sprague Dawley (HSD rats might be caused by underlying variation in clock function. We predicted that HSD rats would have more activity during the day or subjective day, longer free-running rhythms, poor entrainment to short day length, and shorter duration of activity, traits that have been associated with nonphotoperiodism in other laboratory rodent species, relative to F344 rats. An alternative hypothesis, that differences are due to variation in melatonin secretion or responses to melatonin, predicts either no such differences or inconsistent combinations of differences. Methods We tested these predictions by examining activity rhythms of young male F344 and HSD rats given access to running wheels in constant dark (DD, short day length (L8:D16; SD, and long day length (L16:D8; LD. We compared nocturnality (the proportion of activity during night or subjective night, duration of activity (alpha, activity onset and offset, phase angle of entrainment, and free running rhythms (tau of F344 and HSD rats. Results HSD rats had significantly greater activity during the day, were sometimes arrhythmic in DD, and had significantly longer tau than F344 rats, consistent with predictions. However, HSD rats had significantly longer alpha than F344 rats and both strains entrained to SD, inconsistent with predictions. Conclusion The ability of HSD rats to entrain to SD, combined with longer alpha than F344 rats, suggests that the circadian system of HSD rats responds correctly to SD. These data offer best support for the alternative hypothesis, that differences in photoresponsiveness between F344 and HSD rats are caused by non

  9. Microarray analysis of natural socially regulated plasticity in circadian rhythms of honey bees.

    Science.gov (United States)

    Rodriguez-Zas, Sandra L; Southey, Bruce R; Shemesh, Yair; Rubin, Elad B; Cohen, Mira; Robinson, Gene E; Bloch, Guy

    2012-02-01

    Honey bee workers care for ("nurse") the brood around the clock without circadian rhythmicity, but then they forage outside with strong circadian rhythms and a consolidated nightly rest. This chronobiological plasticity is associated with variation in the expression of the canonical "clock genes" that regulate the circadian clock: nurse bees show no brain rhythms of expression, while foragers do. These results suggest that the circadian system is organized differently in nurses and foragers. Nurses switch to activity with circadian rhythms shortly after being removed from the hive, suggesting that at least some clock cells in their brain continue to measure time while in the hive. We performed a microarray genome-wide survey to determine general patterns of brain gene expression in nurses and foragers sampled around the clock. We found 160 and 541 transcripts that exhibited significant sinusoidal oscillations in nurses and foragers, respectively, with peaks of expression distributed throughout the day in both task groups. Consistent with earlier studies, transcripts of genes involved in circadian rhythms, including Clockwork Orange that has not been studied before in bees, oscillated in foragers but not in nurses. The oscillating transcripts also were enriched for genes involved in the visual system, "development" and "response to stimuli" (foragers), "muscle contraction" and "microfilament motor gene expression" (nurses), and "generation of precursor metabolites" and "energy" (both). Transcripts of genes encoding P450 enzymes oscillated in both nurses and foragers but with a different phase. This study identified new putative clock-controlled genes in the honey bee and suggests that some brain functions show circadian rhythmicity even in nurse bees that are active around the clock.

  10. Microarray Analysis of Natural Socially-Regulated Plasticity in Circadian Rhythms of Honey Bees

    Science.gov (United States)

    Rodriguez-Zas, Sandra L.; Southey, Bruce R.; Shemesh, Yair; Rubin, Elad B.; Cohen, Mira; Robinson, Gene E.; Bloch, Guy

    2012-01-01

    Honey bee workers care for ("nurse") the brood around the clock without circadian rhythmicity, but then they forage outside with strong circadian rhythms and a consolidated nightly rest. This chronobiological plasticity is associated with variation in the expression of the canonical “clock genes” that regulate the circadian clock: nurse bees show no brain rhythms of expression, while foragers do. These results suggest that the circadian system is organized differently in nurses and foragers. Nurses switch to activity with circadian rhythms shortly after removed from the hive suggesting that at least some clock cells in their brain continue to measure time while in the hive. We performed a microarray genome-wide survey to determine general patterns of brain gene expression in nurses and foragers sampled around the clock. We found 160 and 541 transcripts that exhibited significant sinusoidal oscillations in nurses and foragers, respectively, with peaks of expression distributed throughout the day in both task groups. Consistent with earlier studies, transcripts of genes involved in circadian rhythms, including Clockwork Orange that has not been studied before in bees, oscillated in foragers but not in nurses. The oscillating transcripts also were enriched for genes involved in the visual system, “development” and “response to stimuli” (foragers), “muscle contraction” and “microfilament motor gene expression” (nurses), and “generation of precursor metabolites” and “energy” (both). Transcripts of genes encoding P450 enzymes oscillated in both nurses and foragers but with a different phase. This study identified new putative clock-controlled genes in the honey bee and suggests that some brain functions show circadian rhythmicity even in nurse bees that are active around the clock. PMID:22306970

  11. Ethics and methods for biological rhythm research on animals and human beings.

    Science.gov (United States)

    Portaluppi, Francesco; Smolensky, Michael H; Touitou, Yvan

    2010-10-01

    This article updates the ethical standards and methods for the conduct of high-quality animal and human biological rhythm research, which should be especially useful for new investigators of the rhythms of life. The editors of Chronobiology International adhere to and endorse the Code of Conduct and Best Practice Guidelines of the Committee On Publication Ethics (COPE), which encourages communication of such updates at regular intervals in the journal. The journal accepts papers representing original work, no part of which was previously submitted for publication elsewhere, except as brief abstracts, as well as in-depth reviews. The majority of research papers published in Chronobiology International entails animal and human investigations. The editors and readers of the journal expect authors of submitted manuscripts to have made an important contribution to the research of biological rhythms and related phenomena using ethical methods/procedures and unbiased, accurate, and honest reporting of findings. Authors of scientific papers are required to declare all potential conflicts of interest. The journal and its editors endorse compliance of investigators to the Guide for the Care and Use of Laboratory Animals of the Institute for Laboratory Animal Research of the National Research Council, relating to the conduct of ethical research on laboratory and other animals, and the principles of the Declaration of Helsinki of the World Medical Association, relating to the conduct of ethical research on human beings. The peer review of manuscripts by Chronobiology International thus includes judgment as to whether or not the protocols and methods conform to ethical standards. Authors are expected to show mastery of the basic methods and procedures of biological rhythm research and proper statistical assessment of data, including the appropriate application of time series data analyses, as briefly reviewed in this article. The journal editors strive to consistently achieve

  12. ERP evidence of adaptive changes in error processing and attentional control during rhythm synchronization learning.

    Science.gov (United States)

    Padrão, Gonçalo; Penhune, Virginia; de Diego-Balaguer, Ruth; Marco-Pallares, Josep; Rodriguez-Fornells, Antoni

    2014-10-15

    The ability to detect and use information from errors is essential during the acquisition of new skills. There is now a wealth of evidence about the brain mechanisms involved in error processing. However, the extent to which those mechanisms are engaged during the acquisition of new motor skills remains elusive. Here we examined rhythm synchronization learning across 12 blocks of practice in musically naïve individuals and tracked changes in ERP signals associated with error-monitoring and error-awareness across distinct learning stages. Synchronization performance improved with practice, and performance improvements were accompanied by dynamic changes in ERP components related to error-monitoring and error-awareness. Early in learning, when performance was poor and the internal representations of the rhythms were weaker we observed a larger error-related negativity (ERN) following errors compared to later learning. The larger ERN during early learning likely results from greater conflict between competing motor responses, leading to greater engagement of medial-frontal conflict monitoring processes and attentional control. Later in learning, when performance had improved, we observed a smaller ERN accompanied by an enhancement of a centroparietal positive component resembling the P3. This centroparietal positive component was predictive of participant's performance accuracy, suggesting a relation between error saliency, error awareness and the consolidation of internal templates of the practiced rhythms. Moreover, we showed that during rhythm learning errors led to larger auditory evoked responses related to attention orientation which were triggered automatically and which were independent of the learning stage. The present study provides crucial new information about how the electrophysiological signatures related to error-monitoring and error-awareness change during the acquisition of new skills, extending previous work on error processing and cognitive

  13. Different origins of gamma rhythm and high-gamma activity in macaque visual cortex.

    Directory of Open Access Journals (Sweden)

    Supratim Ray

    2011-04-01

    Full Text Available During cognitive tasks electrical activity in the brain shows changes in power in specific frequency ranges, such as the alpha (8-12 Hz or gamma (30-80 Hz bands, as well as in a broad range above ∼80 Hz, called the high-gamma band. The role or significance of this broadband high-gamma activity is unclear. One hypothesis states that high-gamma oscillations serve just like gamma oscillations, operating at a higher frequency and consequently at a faster timescale. Another hypothesis states that high-gamma power is related to spiking activity. Because gamma power and spiking activity tend to co-vary during most stimulus manipulations (such as contrast modulations or cognitive tasks (such as attentional modulation, it is difficult to dissociate these two hypotheses. We studied the relationship between high-gamma power, gamma rhythm, and spiking activity in the primary visual cortex (V1 of awake monkeys while varying the stimulus size, which increased the gamma power but decreased the firing rate, permitting a dissociation. We found that gamma power became anti-correlated with the high-gamma power, suggesting that the two phenomena are distinct and have different origins. On the other hand, high-gamma power remained tightly correlated with spiking activity under a wide range of stimulus manipulations. We studied this relationship using a signal processing technique called Matching Pursuit and found that action potentials are associated with sharp transients in the LFP with broadband power, which is visible at frequencies as low as ∼50 Hz. These results distinguish broadband high-gamma activity from gamma rhythms as an easily obtained and reliable electrophysiological index of neuronal firing near the microelectrode. Further, they highlight the importance of making a careful dissociation between gamma rhythms and spike-related transients that could be incorrectly decomposed as rhythms using traditional signal processing methods.

  14. Meta-analysis of randomised controlled trials of the effectiveness of antiarrhythmic agents at promoting sinus rhythm in patients with atrial fibrillation

    Science.gov (United States)

    Nichol, G; McAlister, F; Pham, B; Laupacis, A; Shea, B; Green, M; Tang, A; Wells, G

    2002-01-01

    Objective: To conduct a meta-analysis of randomised controlled trials to estimate the effectiveness of antiarrhythmic drugs at promoting sinus rhythm in patients with atrial fibrillation. Design: Articles were identified by using a comprehensive search of English language papers indexed in Medline from 1966 to August 2001. For the outcomes of sinus rhythm and death, a random effects model was used to model repeated assessments within a study at different time points. Setting: Emergency departments and ambulatory clinics. Patients: Patients with atrial fibrillation. Interventions: Antiarrhythmic agents grouped according to their Vaughan-Williams class. Main outcome measures: Sinus rhythm and mortality. Results: 91 articles met a priori criteria for inclusion in the analysis. Median duration of follow up was one day (range 0.04–1096, mean (SD) 46 (136) days). The median proportion of patients in sinus rhythm at follow up was 55% (range 0–100%) and 32% (range 0–90%) receiving active treatment and placebo, respectively. Median survival was 99% (range 55–100%) and 99% (range 55–100%). Compared with placebo, the following drug classes were associated with increased sinus rhythm at follow up: IA (treatment difference 21.5%, 95% confidence interval (CI) 16.3% to 26.8%); IC (treatment difference 33.1%, 95% CI 23.3% to 42.9%); and III (treatment difference 17.4%, 95% CI 11.5% to 23.3%). Class IC drugs were associated with increased sinus rhythm at follow up compared with class IV drugs (treatment difference 43.2%, 95% CI 11.5% to 75.0%). There was no significant difference in mortality between any drug classes. Conclusions: Class IA, IC, and III drugs are associated with increased sinus rhythm at follow up compared with placebo. It is unclear whether any antiarrhythmic drug class is associated with increased or decreased mortality. PMID:12010934

  15. Circadian rhythms in floral scent emission

    Directory of Open Access Journals (Sweden)

    Myles eFenske

    2016-04-01

    Full Text Available To successfully recruit pollinators, plants often release attractive floral scents at specific times of day to coincide with pollinator foraging. This timing of scent emission is thought to be evolutionarily beneficial to maximize resource efficiency while attracting only useful pollinators. Temporal regulation of scent emission is tied to the activity of the specific metabolic pathways responsible for scent production. Although floral volatile profiling in various plants indicated a contribution by the circadian clock, the mechanisms by which the circadian clock regulates timing of floral scent emission remained elusive. Recent studies using two species in the Solanaceae family provided initial insight into molecular clock regulation of scent emission timing. In Petunia hybrida, the benzenoid/phenylpropanoid (FVBP pathway is the major metabolic pathway that produces floral volatiles. Three MYB-type transcription factors, ODORANT1 (ODO1, EMISSION OF BENZENOIDS I (EOBI, and EOBII, all of which show diurnal rhythms in mRNA expression, act as positive regulators for several enzyme genes in the FVBP pathway. Recently, in P. hybrida and Nicotiana attenuata, homologs of the Arabidopsis clock gene LATE ELONGATED HYPOCOTYL (LHY have been shown to have a similar role in the circadian clock in these plants, and to also determine the timing of scent emission. In addition, in P. hybrida, PhLHY directly represses ODO1 and several enzyme genes in the FVBP pathway during the morning as an important negative regulator of scent emission. These findings facilitate our understanding of the relationship between a molecular timekeeper and the timing of scent emission, which may influence reproductive success.

  16. Physiological basis for human autonomic rhythms

    Science.gov (United States)

    Eckberg, D. L.

    2000-01-01

    Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

  17. Brain rhythms reveal a hierarchical network organization.

    Directory of Open Access Journals (Sweden)

    G Karl Steinke

    2011-10-01

    Full Text Available Recordings of ongoing neural activity with EEG and MEG exhibit oscillations of specific frequencies over a non-oscillatory background. The oscillations appear in the power spectrum as a collection of frequency bands that are evenly spaced on a logarithmic scale, thereby preventing mutual entrainment and cross-talk. Over the last few years, experimental, computational and theoretical studies have made substantial progress on our understanding of the biophysical mechanisms underlying the generation of network oscillations and their interactions, with emphasis on the role of neuronal synchronization. In this paper we ask a very different question. Rather than investigating how brain rhythms emerge, or whether they are necessary for neural function, we focus on what they tell us about functional brain connectivity. We hypothesized that if we were able to construct abstract networks, or "virtual brains", whose dynamics were similar to EEG/MEG recordings, those networks would share structural features among themselves, and also with real brains. Applying mathematical techniques for inverse problems, we have reverse-engineered network architectures that generate characteristic dynamics of actual brains, including spindles and sharp waves, which appear in the power spectrum as frequency bands superimposed on a non-oscillatory background dominated by low frequencies. We show that all reconstructed networks display similar topological features (e.g. structural motifs and dynamics. We have also reverse-engineered putative diseased brains (epileptic and schizophrenic, in which the oscillatory activity is altered in different ways, as reported in clinical studies. These reconstructed networks show consistent alterations of functional connectivity and dynamics. In particular, we show that the complexity of the network, quantified as proposed by Tononi, Sporns and Edelman, is a good indicator of brain fitness, since virtual brains modeling diseased states

  18. [Psychoeducation and interpersonal and social rhythm therapy for bipolar disorder].

    Science.gov (United States)

    Mizushima, Hiroko

    2011-01-01

    In treating bipolar disorder, specific psychotherapies in adjunct to pharmacotherapy have been shown to be effective in preventing new episodes and treating depressive episodes. Among those, interpersonal and social rhythm therapy (IPSRT) developed by Frank, amalgamation of interpersonal psychotherapy (IPT) with behavioral therapy focused on social rhythm has been shown to be an efficacious adjunct to mediation in preventing new episodes in bipolar I patients and in treating depression in bipolar I arid II disorder. IPSRT has also been shown to enhance total functioning, relationship functioning and life satisfaction among patients with bipolar disorder, even after pretreatment functioning and concurrent depression were covaried. IPSRT was designed to directly address the major pathways to recurrence in bipolar disorder, namely medication nonadherence, stressful life events, and disruptions in social rhythms. IPT, originated by Klerman et al., is a strategic time-limited psychotherapy focused on one or two of four current interpersonal problem areas (ie, grief, interpersonal role disputes, role transitions, and interpersonal dificits). In IPSRT, the fifth problem area "grief for the lost healthy self" has been added in order to promote acceptance of the diagnosis and the need for life-long treatment. Social rhythm therapy is a behavioral approach aiming at increasing regularity of social rhythms using the Social Rhythm Metric (SRM), a chart to record daily social activities including how stimulating they were, developed from observation that disruptions in social rhythms often trigger affective episodes in patients with bipolar disorder. IPSRT also appears to be a promising intervention for a subset of individuals with bipolar II depression as monotherapy for the acute treatment.

  19. Biological rhythms in the human life cycle and their relationship to functional changes in the suprachiasmatic nucleus

    NARCIS (Netherlands)

    Swaab, D. F.; van Someren, E. J.; Zhou, J. N.; Hofman, M. A.

    1996-01-01

    Biological rhythms play a prominent role in the human life cycle. The endogenous rhythms are entrained by the environment and have an astronomical counterpart which is obvious for daily, monthly, and yearly rhythms, and may possibly also be present in weekly rhythms. Circadian rhythms are present

  20. Performance of the biological rhythms interview for assessment in neuropsychiatry: An item response theory and actigraphy analysis.

    Science.gov (United States)

    Allega, Olivia R; Leng, Xiamin; Vaccarino, Anthony; Skelly, Matthew; Lanzini, Mariana; Hidalgo, Maria Paz; Soares, Claudio N; Kennedy, Sidney H; Frey, Benicio N

    2018-01-01

    Biological rhythm disturbances are widely associated with the pathophysiology of mood disorders. The Biological Rhythms Interview for Assessment in Neuropsychiatry (BRIAN) is a self-report that indexes rhythm disturbance in sleep, activity, social and eating patterns. The aim of this study was to perform an Item Response Theory (IRT) analysis of the BRIAN and investigate its associations with objective sleep and rhythm disturbance measures. 103 subjects (31 bipolar, 32 major depression and 40 healthy volunteers) wore an actiwatch for fifteen days, and completed a first morning urine sample and the BRIAN on day 15. IRT analysis assessed individual BRIAN items and their relationship to total score. Individual actiwatch records were processed to produce a sequence of transitions between rest/activity, and a likelihood of transitioning between states was calculated to investigate sleep-wake dynamics. Cosinor analysis produced daily activity rhythms (DARs). Spearman correlations were used to assess the association between sleep/DAR variables and the BRIAN. IRT analyses showed that 11 of 18 BRIAN items displayed a high level of discrimination between item options across a range of BRIAN total scores. Total BRIAN score correlated with wake after sleep onset, total activity count during sleep, and urinary 6-sulphatoxymelatonin. BRIAN Activity domain correlated with the daytime transition probability from rest to activity. The sample size may have been underpowered for the graded-response model employed in IRT. The study lacked an objective comparison for BRIAN eating and social domain. The present study reveals the BRIAN displays promising external validity compared to objective parameters of circadian rhythmicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Rhythms in the endocrine system of fish: a review.

    Science.gov (United States)

    Cowan, Mairi; Azpeleta, Clara; López-Olmeda, Jose Fernando

    2017-12-01

    The environment which living organisms inhabit is not constant and many factors, such as light, temperature, and food availability, display cyclic and predictable variations. To adapt to these cyclic changes, animals present biological rhythms in many of their physiological variables, timing their functions to occur when the possibility of success is greatest. Among these variables, many endocrine factors have been described as displaying rhythms in vertebrates. The aim of the present review is to provide a thorough review of the existing knowledge on the rhythms of the endocrine system of fish by examining the hormones that show rhythmicity, how environmental factors control these rhythms and the variation in the responses of the endocrine system depending on the time of the day. We mainly focused on the hypothalamic-pituitary axis, which can be considered as the master axis of the endocrine system of vertebrates and regulates a great variety of functions, including reproduction, growth, metabolism, energy homeostasis, stress response, and osmoregulation. In addition, the rhythms of other hormones, such as melatonin and the factors, produced in the gastrointestinal system of fish are reviewed.

  2. Social Rhythm and Mental Health: A Cross-Cultural Comparison

    Science.gov (United States)

    Margraf, Jürgen; Lavallee, Kristen; Zhang, XiaoChi; Schneider, Silvia

    2016-01-01

    Background Social rhythm refers to the regularity with which one engages in social activities throughout the week, and has established links with bipolar disorder, as well as some links with depression and anxiety. The aim of the present study is to examine social rhythm and its relationship to various aspects of health, including physical health, negative mental health, and positive mental health. Method Questionnaire data were obtained from a large-scale multi-national sample of 8095 representative participants from the U.S., Russia, and Germany. Results Results indicated that social rhythm irregularity is related to increased reporting of health problems, depression, anxiety, and stress. In contrast, greater regularity is related to better overall health state, life satisfaction, and positive mental health. The effects are generally small in size, but hold even when controlling for gender, marital status, education, income, country, and social support. Further, social rhythm means differ across Russia, the U.S., and Germany. Relationships with mental health are present in all three countries, but differ in magnitude. Conclusions Social rhythm irregularity is related to mental health in Russia, the U.S., and Germany. PMID:26954568

  3. Pathophysiology and pathogenesis of circadian rhythm sleep disorders

    Directory of Open Access Journals (Sweden)

    Hida Akiko

    2012-03-01

    Full Text Available Abstract Metabolic, physiological and behavioral processes exhibit 24-hour rhythms in most organisms, including humans. These rhythms are driven by a system of self-sustained clocks and are entrained by environmental cues such as light-dark cycles as well as food intake. In mammals, the circadian clock system is hierarchically organized such that the master clock in the suprachiasmatic nuclei of the hypothalamus integrates environmental information and synchronizes the phase of oscillators in peripheral tissues. The transcription and translation feedback loops of multiple clock genes are involved in the molecular mechanism of the circadian system. Disturbed circadian rhythms are known to be closely related to many diseases, including sleep disorders. Advanced sleep phase type, delayed sleep phase type and nonentrained type of circadian rhythm sleep disorders (CRSDs are thought to result from disorganization of the circadian system. Evaluation of circadian phenotypes is indispensable to understanding the pathophysiology of CRSD. It is laborious and costly to assess an individual's circadian properties precisely, however, because the subject is usually required to stay in a laboratory environment free from external cues and masking effects for a minimum of several weeks. More convenient measurements of circadian rhythms are therefore needed to reduce patients' burden. In this review, we discuss the pathophysiology and pathogenesis of CRSD as well as surrogate measurements for assessing an individual's circadian phenotype.

  4. Social Rhythm and Mental Health: A Cross-Cultural Comparison.

    Directory of Open Access Journals (Sweden)

    Jürgen Margraf

    Full Text Available Social rhythm refers to the regularity with which one engages in social activities throughout the week, and has established links with bipolar disorder, as well as some links with depression and anxiety. The aim of the present study is to examine social rhythm and its relationship to various aspects of health, including physical health, negative mental health, and positive mental health.Questionnaire data were obtained from a large-scale multi-national sample of 8095 representative participants from the U.S., Russia, and Germany.Results indicated that social rhythm irregularity is related to increased reporting of health problems, depression, anxiety, and stress. In contrast, greater regularity is related to better overall health state, life satisfaction, and positive mental health. The effects are generally small in size, but hold even when controlling for gender, marital status, education, income, country, and social support. Further, social rhythm means differ across Russia, the U.S., and Germany. Relationships with mental health are present in all three countries, but differ in magnitude.Social rhythm irregularity is related to mental health in Russia, the U.S., and Germany.

  5. Establishment of human cell lines showing circadian rhythms of bioluminescence.

    Science.gov (United States)

    Yoshikawa, Aki; Shimada, Hiroko; Numazawa, Kahori; Sasaki, Tsukasa; Ikeda, Masaaki; Kawashima, Minae; Kato, Nobumasa; Tokunaga, Katsushi; Ebisawa, Takashi

    2008-11-28

    We have established human retinal pigment epithelial cell lines stably expressing the luciferase gene, driven by the human Bmal1 promoter, to obtain human-derived cells that show circadian rhythms of bioluminescence after dexamethasone treatment. The average circadian period of bioluminescence for the obtained clones was 24.07+/-0.48 h. Lithium (10 mM) in the medium significantly lengthened the circadian period of bioluminescence, which is consistent with previous reports, while 2 mM or 5 mM lithium had no effect. This is the first report on the establishment of human-derived cell lines that proliferate infinitely and show circadian rhythms of bioluminescence, and also the first to investigate the effects of low-dose lithium on the circadian rhythms of human-derived cells in vitro. The established cells will be useful for various in vitro studies of human circadian rhythms and for the development of new therapies for human disorders related to circadian rhythm disturbances.

  6. Phase advance of circadian rhythms in Smith-Magenis syndrome: a case study in an adult man.

    Science.gov (United States)

    Kocher, Laurence; Brun, Jocelyne; Devillard, Françoise; Azabou, Eric; Claustrat, Bruno

    2015-01-12

    Melatonin secretion is usually increased during the daytime and decreased at night in Smith-Magenis syndrome (SMS) and consequently is not a pertinent marker of the circadian phase of the clock in these cases. No data on temperature rhythm is available in SMS, another reliable marker of circadian clock activity. For this reason, we assessed the 24h profiles of core temperature, sleep-wake cycle, hormones (plasma cortisol and melatonin) and plasma and urine 6sulfatoxy-melatonin, the main hepatic melatonin metabolism in a 31-year-old man diagnosed with a SMS. All circadian rhythms, especially temperature rhythm showed a phase-advance, associated with reverse melatonin secretion. Plasma and urine 6sulfatoxy-melatonin profiles showed normal melatonin catabolism and confirmed the reversed melatonin secretion. Taking in consideration the reverse melatonin secretion and the phase-advanced temperature rhythm, which is driven by the suprachiasmatic nucleus, we hypothesize that the central clock is more sensitive to afternoon than to morning melatonin. This different responsiveness to melatonin according to the time of the day (i.e. chronaesthesia) corroborates the phase response curve of melatonin secretion to exogenous melatonin. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Relationship between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone

    Directory of Open Access Journals (Sweden)

    Suge Rie

    2011-09-01

    Full Text Available Abstract Background In university health care settings, students with psychosomatic complaints often have chronotypic problems. For this reason, we investigated a potential connection between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone. Methods Fifteen healthy students between 21 and 22 years of age were examined for physiological parameters of chronotypes based on melatonin and growth hormone secretion patterns, using a fluorescence enzyme immunoassay. Salivary samples were collected from subjects at home five times each day (20:00, 24:00, 04:00, 08:00, and 12:00 h. In addition, the subjects rated their psychosomatic symptoms twice (at 08:00 and 20:00 h. Results A group with irregular circadian rhythm of melatonin (ICR showed more psychosomatic complaints than a group with the regular circadian rhythm (RCR, especially for anxiety. Conclusion Psychosomatic symptoms, particularly anxiety, may be associated with irregularity in melatonin and growth hormone rhythms, which can be altered by basic lifestyle habits even in healthy students.

  8. Epigenetic Regulation of Biological Rhythms: An Evolutionary Ancient Molecular Timer.

    Science.gov (United States)

    Stevenson, Tyler J

    2017-12-05

    Biological rhythms are pervasive in nature, yet our understanding of the molecular mechanisms that govern timing is far from complete. The rapidly emerging research focus on epigenetic plasticity has revealed a system that is highly dynamic and reversible. In this Opinion, I propose an epigenetic clock model that outlines how molecular modifications, such as DNA methylation, are integral components for timing endogenous biological rhythms. The hypothesis proposed is that an epigenetic clock serves to maintain the period of molecular rhythms via control over the phase of gene transcription and this timing mechanism resides in all cells, from unicellular to complex organisms. The model also provides a novel framework for the timing of epigenetic modifications during the lifespan and transgenerational inheritance of an organism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Circadian rhythms, time-restricted feeding, and healthy aging.

    Science.gov (United States)

    Manoogian, Emily N C; Panda, Satchidananda

    2017-10-01

    Circadian rhythms optimize physiology and health by temporally coordinating cellular function, tissue function, and behavior. These endogenous rhythms dampen with age and thus compromise temporal coordination. Feeding-fasting patterns are an external cue that profoundly influence the robustness of daily biological rhythms. Erratic eating patterns can disrupt the temporal coordination of metabolism and physiology leading to chronic diseases that are also characteristic of aging. However, sustaining a robust feeding-fasting cycle, even without altering nutrition quality or quantity, can prevent or reverse these chronic diseases in experimental models. In humans, epidemiological studies have shown erratic eating patterns increase the risk of disease, whereas sustained feeding-fasting cycles, or prolonged overnight fasting, is correlated with protection from breast cancer. Therefore, optimizing the timing of external cues with defined eating patterns can sustain a robust circadian clock, which may prevent disease and improve prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Current Conceptual Challenges in the Study of Rhythm Processing Deficits

    Directory of Open Access Journals (Sweden)

    Pauline eTranchant

    2015-06-01

    Full Text Available Interest in the study of rhythm processing deficits (RPD is currently growing in the cognitive neuroscience community, as this type of investigation constitutes a powerful tool for the understanding of normal rhythm processing. Because this field is in its infancy, it still lacks a common conceptual vocabulary to facilitate effective communication between different researchers and research groups. In this commentary, we provide a brief review of recent reports of RPD through the lens of one important empirical issue: the method by which beat perception is measured, and the consequences of method selection for the researcher’s ability to specify which mechanisms are impaired in RPD. This critical reading advocates for the importance of matching measurement tools to the putative neurocognitive mechanisms under study, and reveals the need for effective and specific assessments of the different aspects of rhythm perception and synchronization.

  11. Into the groove: can rhythm influence Parkinson's disease?

    Science.gov (United States)

    Nombela, Cristina; Hughes, Laura E; Owen, Adrian M; Grahn, Jessica A

    2013-12-01

    Previous research has noted that music can improve gait in several pathological conditions, including Parkinson's disease, Huntington's disease and stroke. Current research into auditory-motor interactions and the neural bases of musical rhythm perception has provided important insights for developing potential movement therapies. Specifically, neuroimaging studies show that rhythm perception activates structures within key motor networks, such as premotor and supplementary motor areas, basal ganglia and the cerebellum - many of which are compromised to varying degrees in Parkinson's disease. It thus seems likely that automatic engagement of motor areas during rhythm perception may be the connecting link between music and motor improvements in Parkinson's disease. This review seeks to describe the link, address core questions about its underlying mechanisms, and examine whether it can be utilized as a compensatory mechanism. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Rhythm as an affordance for the entrainment of movement.

    Science.gov (United States)

    Cummins, Fred

    2009-01-01

    A general account of rhythm in human behaviour is provided, according to which rhythm inheres in the affordance that a signal provides for the entrainment of movement on the part of a perceiver. This generic account is supported by an explication of the central concepts of affordance and entrainment. When viewed in this light, rhythm appears as the correct explanandum to account for coordinated behaviour in a wide variety of situations, including such core senses as dance and the production of music. Speech may appear to be only marginally rhythmical under such an account, but several experimental studies reveal that speech, too, has the potential to entrain movement. (c) 2009 S. Karger AG, Basel.

  13. Inositols affect the mating circadian rhythm of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Kazuki eSakata

    2015-06-01

    Full Text Available Accumulating evidence indicates that the molecular circadian clock underlies the mating behavior of D. melanogaster. However, information about which food components affect circadian mating behavior is scant. The ice plant, Mesembryanthemum crystallinum has recently become a popular functional food. Here, we showed that the close-proximity (CP rhythm of Drosophila melanogaster courtship behavior was damped under low-nutrient conditions, but significantly enhanced by feeding the flies with powdered ice plant. Among various components of ice plants, we found that myo-inositol increased the amplitude and slightly shortened the period of the CP rhythm. Real-time reporter assays showed that myo-inositol and D-pinitol shortened the period of the circadian reporter gene Per2-luc in NIH 3T3 cells. These data suggest that the ice plant is a useful functional food and that the ability of inositols to shorten rhythms is a general phenomenon in insects as well as mammals.

  14. Rhythm generation through period concatenation in rat somatosensory cortex.

    Directory of Open Access Journals (Sweden)

    Mark A Kramer

    2008-09-01

    Full Text Available Rhythmic voltage oscillations resulting from the summed activity of neuronal populations occur in many nervous systems. Contemporary observations suggest that coexistent oscillations interact and, in time, may switch in dominance. We recently reported an example of these interactions recorded from in vitro preparations of rat somatosensory cortex. We found that following an initial interval of coexistent gamma ( approximately 25 ms period and beta2 ( approximately 40 ms period rhythms in the superficial and deep cortical layers, respectively, a transition to a synchronous beta1 ( approximately 65 ms period rhythm in all cortical layers occurred. We proposed that the switch to beta1 activity resulted from the novel mechanism of period concatenation of the faster rhythms: gamma period (25 ms+beta2 period (40 ms = beta1 period (65 ms. In this article, we investigate in greater detail the fundamental mechanisms of the beta1 rhythm. To do so we describe additional in vitro experiments that constrain a biologically realistic, yet simplified, computational model of the activity. We use the model to suggest that the dynamic building blocks (or motifs of the gamma and beta2 rhythms combine to produce a beta1 oscillation that exhibits cross-frequency interactions. Through the combined approach of in vitro experiments and mathematical modeling we isolate the specific components that promote or destroy each rhythm. We propose that mechanisms vital to establishing the beta1 oscillation include strengthened connections between a population of deep layer intrinsically bursting cells and a transition from antidromic to orthodromic spike generation in these cells. We conclude that neural activity in the superficial and deep cortical layers may temporally combine to generate a slower oscillation.

  15. ACC/AATS/AHA/ASE/ASNC/HRS/SCAI/SCCT/SCMR/STS 2017 Appropriate Use Criteria for Multimodality Imaging in Valvular Heart Disease: A Report of the American College of Cardiology Appropriate Use Criteria Task Force, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    Science.gov (United States)

    Doherty, John U; Kort, Smadar; Mehran, Roxana; Schoenhagen, Paul; Soman, Prem; Dehmer, Greg J; Doherty, John U; Schoenhagen, Paul; Amin, Zahid; Bashore, Thomas M; Boyle, Andrew; Calnon, Dennis A; Carabello, Blase; Cerqueira, Manuel D; Conte, John; Desai, Milind; Edmundowicz, Daniel; Ferrari, Victor A; Ghoshhajra, Brian; Mehrotra, Praveen; Nazarian, Saman; Reece, T Brett; Tamarappoo, Balaji; Tzou, Wendy S; Wong, John B; Doherty, John U; Dehmer, Gregory J; Bailey, Steven R; Bhave, Nicole M; Brown, Alan S; Daugherty, Stacie L; Dean, Larry S; Desai, Milind Y; Duvernoy, Claire S; Gillam, Linda D; Hendel, Robert C; Kramer, Christopher M; Lindsay, Bruce D; Manning, Warren J; Mehrotra, Praveen; Patel, Manesh R; Sachdeva, Ritu; Wann, L Samuel; Winchester, David E; Wolk, Michael J; Allen, Joseph M

    2017-10-20

    This document is 1 of 2 companion appropriate use criteria (AUC) documents developed by the American College of Cardiology, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons. This document addresses the evaluation and use of multimodality imaging in the diagnosis and management of valvular heart disease, whereas the second, companion document addresses this topic with regard to structural heart disease. Although there is clinical overlap, the documents addressing valvular and structural heart disease are published separately, albeit with a common structure. The goal of the companion AUC documents is to provide a comprehensive resource for multimodality imaging in the context of valvular and structural heart disease, encompassing multiple imaging modalities. Using standardized methodology, the clinical scenarios (indications) were developed by a diverse writing group to represent patient presentations encountered in everyday practice and included common applications and anticipated uses. Where appropriate, the scenarios were developed on the basis of the most current American College of Cardiology/American Heart Association guidelines. A separate, independent rating panel scored the 92 clinical scenarios in this document on a scale of 1 to 9. Scores of 7 to 9 indicate that a modality is considered appropriate for the clinical scenario presented. Midrange scores of 4 to 6 indicate that a modality may be appropriate for the clinical scenario, and scores of 1 to 3 indicate that a modality is considered rarely appropriate for the clinical scenario. The primary objective of the AUC is to provide a framework for the assessment of these scenarios by practices that will

  16. ACC/AATS/AHA/ASE/ASNC/HRS/SCAI/SCCT/SCMR/STS 2017 Appropriate Use Criteria for Multimodality Imaging in Valvular Heart Disease : A Report of the American College of Cardiology Appropriate Use Criteria Task Force, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    Science.gov (United States)

    Doherty, John U; Kort, Smadar; Mehran, Roxana; Schoenhagen, Paul; Soman, Prem

    2017-12-01

    This document is 1 of 2 companion appropriate use criteria (AUC) documents developed by the American College of Cardiology, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons. This document addresses the evaluation and use of multimodality imaging in the diagnosis and management of valvular heart disease, whereas the second, companion document addresses this topic with regard to structural heart disease. Although there is clinical overlap, the documents addressing valvular and structural heart disease are published separately, albeit with a common structure. The goal of the companion AUC documents is to provide a comprehensive resource for multimodality imaging in the context of valvular and structural heart disease, encompassing multiple imaging modalities.Using standardized methodology, the clinical scenarios (indications) were developed by a diverse writing group to represent patient presentations encountered in everyday practice and included common applications and anticipated uses. Where appropriate, the scenarios were developed on the basis of the most current American College of Cardiology/American Heart Association guidelines.A separate, independent rating panel scored the 92 clinical scenarios in this document on a scale of 1 to 9. Scores of 7 to 9 indicate that a modality is considered appropriate for the clinical scenario presented. Midrange scores of 4 to 6 indicate that a modality may be appropriate for the clinical scenario, and scores of 1 to 3 indicate that a modality is considered rarely appropriate for the clinical scenario.The primary objective of the AUC is to provide a framework for the assessment of these scenarios by practices that will

  17. Ethical and methodological standards for laboratory and medical biological rhythm research.

    Science.gov (United States)

    Portaluppi, Francesco; Touitou, Yvan; Smolensky, Michael H

    2008-11-01

    The main objectives of this article are to update the ethical standards for the conduct of human and animal biological rhythm research and recommend essential elements for quality chronobiological research information, which should be especially useful for new investigators of the rhythms of life. A secondary objective is to provide for those with an interest in the results of chronobiology investigations, but who might be unfamiliar with the field, an introduction to the basic methods and standards of biological rhythm research and time series data analysis. The journal and its editors endorse compliance of all investigators to the principles of the Declaration of Helsinki of the World Medical Association, which relate to the conduct of ethical research on human beings, and the Guide for the Care and Use of Laboratory Animals of the Institute for Laboratory Animal Research of the National Research Council, which relate to the conduct of ethical research on laboratory and other animals. The editors and the readers of the journal expect the authors of submitted manuscripts to have adhered to the ethical standards dictated by local, national, and international laws and regulations in the conduct of investigations and to be unbiased and accurate in reporting never-before-published research findings. Authors of scientific papers are required to disclose all potential conflicts of interest, particularly when the research is funded in part or in full by the medical and pharmaceutical industry, when the authors are stock-holders of the company that manufactures or markets the products under study, or when the authors are a recent or current paid consultant to the involved company. It is the responsibility of the authors of submitted manuscripts to clearly present sufficient detail about the synchronizer schedule of the studied subjects (i.e., the sleep-wake schedule, ambient light-dark cycle, intensity and spectrum of ambient light exposure, seasons when the research was

  18. Neuropeptide signaling differentially affects phase maintenance and rhythm generation in SCN and extra-SCN circadian oscillators.

    Directory of Open Access Journals (Sweden)

    Alun T L Hughes

    2011-04-01

    Full Text Available Circadian rhythms in physiology and behavior are coordinated by the brain's dominant circadian pacemaker located in the suprachiasmatic nuclei (SCN of the hypothalamus. Vasoactive intestinal polypeptide (VIP and its receptor, VPAC(2, play important roles in the functioning of the SCN pacemaker. Mice lacking VPAC(2 receptors (Vipr2(-/- express disrupted behavioral and metabolic rhythms and show altered SCN neuronal activity and clock gene expression. Within the brain, the SCN is not the only site containing endogenous circadian oscillators, nor is it the only site of VPAC(2 receptor expression; both VPAC(2 receptors and rhythmic clock gene/protein expression have been noted in the arcuate (Arc and dorsomedial (DMH nuclei of the mediobasal hypothalamus, and in the pituitary gland. The functional role of VPAC(2 receptors in rhythm generation and maintenance in these tissues is, however, unknown. We used wild type (WT and Vipr2(-/- mice expressing a luciferase reporter (PER2::LUC to investigate whether circadian rhythms in the clock gene protein PER2 in these extra-SCN tissues were compromised by the absence of the VPAC(2 receptor. Vipr2(-/- SCN cultures expressed significantly lower amplitude PER2::LUC oscillations than WT SCN. Surprisingly, in Vipr2(-/- Arc/ME/PT complex (Arc, median eminence and pars tuberalis, DMH and pituitary, the period, amplitude and rate of damping of rhythms were not significantly different to WT. Intriguingly, while we found WT SCN and Arc/ME/PT tissues to maintain a consistent circadian phase when cultured, the phase of corresponding Vipr2(-/- cultures was reset by cull/culture procedure. These data demonstrate that while the main rhythm parameters of extra-SCN circadian oscillations are maintained in Vipr2(-/- mice, the ability of these oscillators to resist phase shifts is compromised. These deficiencies may contribute towards the aberrant behavior and metabolism associated with Vipr2(-/- animals. Further, our data

  19. On the presence of a peculiar alpha rhythm in the olfactory tubercle of waking armadillos.

    Science.gov (United States)

    García Samartino, L; Affanni, J M; Casanave, E B; Ferrari, R; Iodice, O

    1987-02-01

    A very regular 8-12 rhythm was found in the olfactory tubercle of the armadillo Chaetophractus villosus. The rhythm was observed during wakefulness. Considerable sinusoidal activity was also observed not only during wakefulness, but during synchronized (slow) and desynchronized (paradoxical) sleep. The significance of this novel rhythm is discussed together with considerations that establish an important difference between it and the other 'alpha rhythms' known.

  20. Sleep, Rhythms, and the Endocrine Brain: Influence of Sex and Gonadal Hormones

    OpenAIRE

    Mong, Jessica A.; Baker, Fiona C.; Mahoney, Megan M.; Paul, Ketema N.; Schwartz, Michael D.; Semba, Kazue; Silver, Rae

    2011-01-01

    While much is known about the mechanisms that underlie sleep and circadian rhythms, the investigation into sex differences and gonadal steroid modulation of sleep and biological rhythms is in its infancy. There is a growing recognition of sex disparities in sleep and rhythm disorders. Understanding how neuroendocrine mediators and sex differences influence sleep and biological rhythms is central to advancing our understanding of sleep-related disorders. While it is known that ovarian steroids...

  1. Integrating new approaches to atrial fibrillation management

    DEFF Research Database (Denmark)

    Kotecha, Dipak; Breithardt, Günter; Camm, A John

    2018-01-01

    cardiovascular events. New approaches to AF management, including the use of novel technologies and structured, integrated care, have the potential to enhance clinical phenotyping or result in better treatment selection and stratified therapy. Here, we report the outcomes of the 6th Consensus Conference...... of the Atrial Fibrillation Network (AFNET) and the European Heart Rhythm Association (EHRA), held at the European Society of Cardiology Heart House in Sophia Antipolis, France, 17-19 January 2017. Sixty-two global specialists in AF and 13 industry partners met to develop innovative solutions based on new...

  2. Harnessing functional segregation across brain rhythms as a means to detect EEG oscillatory multiplexing during music listening.

    Science.gov (United States)

    Adamos, Dimitrios A; Laskaris, Nikolaos; Micheloyannis, Sifis

    2018-02-01

    Objective. Music, being a multifaceted stimulus evolving at multiple timescales, modulates brain function in a manifold way that encompasses not only the distinct stages of auditory perception, but also higher cognitive processes like memory and appraisal. Network theory is apparently a promising approach to describe the functional reorganization of brain oscillatory dynamics during music listening. However, the music induced changes have so far been examined within the functional boundaries of isolated brain rhythms. Approach. Using naturalistic music, we detected the functional segregation patterns associated with different cortical rhythms, as these were reflected in the surface EEG measurements. The emerged structure was compared across frequency bands to quantify the interplay among rhythms. It was also contrasted against the structure from the rest and noise listening conditions to reveal the specific components stemming from music listening. Our methodology includes an efficient graph-partitioning algorithm, which is further utilized for mining prototypical modular patterns, and a novel algorithmic procedure for identifying "switching nodes" (i.e. recording sites) that consistently change module during music listening. Main results. Our results suggest the multiplex character of the music-induced functional reorganization and particularly indicate the dependence between the networks reconstructed from the δ and βH rhythms. This dependence is further justified within the framework of nested neural oscillations and fits perfectly within the context of recently introduced cortical entrainment to music. Significance. Complying with the contemporary trends towards a multi-scale examination of the brain network organization, our approach specifies the form of neural coordination among rhythms during music listening. Considering its computational efficiency, and in conjunction with the flexibility of in situ

  3. Circadian rhythm of proteinuria: consequences of the use of urinary protein:creatinine ratios

    NARCIS (Netherlands)

    Koopman, M. G.; Krediet, R. T.; Koomen, G. C.; Strackee, J.; Arisz, L.

    1989-01-01

    Proteinuria in patients with glomerular disease has a circadian rhythm, but for creatinine such a rhythm is either absent or of low amplitude. We found in 18 of 23 admitted patients (group I) and in seven outpatients (group II) a marked circadian rhythm of the protein: creatinine ratio. Estimates of

  4. Circadian Sleep-Wake Rhythm of Older Adults with Intellectual Disabilities

    Science.gov (United States)

    Maaskant, Marijke; van de Wouw, Ellen; van Wijck, Ruud; Evenhuis, Heleen M.; Echteld, Michael A.

    2013-01-01

    The circadian sleep-wake rhythm changes with aging, resulting in a more fragmented sleep-wake pattern. In individuals with intellectual disabilities (ID), brain structures regulating the sleep-wake rhythm might be affected. The aims of this study were to compare the sleep-wake rhythm of older adults with ID to that of older adults in the general…

  5. Forced desynchrony of circadian rhythms of body temperature and activity in rats

    NARCIS (Netherlands)

    Strijkstra, AM; Meerlo, P; Beersma, DGM

    1999-01-01

    The daily rhythm in body temperature is thought to be the result of the direct effects of activity and the effects of an endogenous circadian clock. Forced desynchrony (FD) is a tool used in human circadian rhythm research to disentangle endogenous and activity-related effects on daily rhythms. In

  6. Perceiving Speech Rhythm in Music: Listeners Classify Instrumental Songs According to Language of Origin

    Science.gov (United States)

    Hannon, Eric E.

    2009-01-01

    Recent evidence suggests that the musical rhythm of a particular culture may parallel the speech rhythm of that culture's language (Patel, A. D., & Daniele, J. R. (2003). "An empirical comparison of rhythm in language and music." "Cognition, 87," B35-B45). The present experiments aimed to determine whether listeners actually perceive such rhythmic…

  7. Sleep, 24-hour activity rhythms, and brain structure : A population-based study

    NARCIS (Netherlands)

    L.A. Zuurbier (Lisette)

    2016-01-01

    markdownabstractIn this thesis, Chapter 2 focuses on sleep, 24-hour activity rhythms and health. Chapter 2.1 describes the influence of demographics, lifestyle and sleep on 24-hour activity rhythms. In Chapter 2.2 sleep and 24-hour activity rhythms are used to predict mortality. This chapter is

  8. Circadian sleep-wake rhythm of older adults with intellectual disabilities

    NARCIS (Netherlands)

    Maaskant, Marijke; van de Wouw, Ellen; van Wijck, Ruud; Evenhuis, Heleen M.; Echteld, Michael A.

    The circadian sleep-wake rhythm changes with aging, resulting in a more fragmented sleep-wake pattern. In individuals with intellectual disabilities (ID), brain structures regulating the sleep-wake rhythm might be affected. The aims of this study were to compare the sleep-wake rhythm of older adults

  9. Rhythm Perception and Its Role in Perception and Learning of Dysrhythmic Speech

    Science.gov (United States)

    Borrie, Stephanie A.; Lansford, Kaitlin L.; Barrett, Tyson S.

    2017-01-01

    Purpose: The perception of rhythm cues plays an important role in recognizing spoken language, especially in adverse listening conditions. Indeed, this has been shown to hold true even when the rhythm cues themselves are dysrhythmic. This study investigates whether expertise in rhythm perception provides a processing advantage for perception…

  10. African Rhythms for flute, clarinet, violin, cello, percussion and piano ...

    African Journals Online (AJOL)

    African Rhythms approaches composition from an intercultural perspective in that it amalgamates musical elements and processes from African and Western art music cultures. Minimalism co-exists with Western compositional devices with an added aspect of intercultural activity by using orchestral instruments in African ...

  11. Perception of timbre and rhythm similarity in electronic dance music

    NARCIS (Netherlands)

    Honingh, A.; Panteli, M.; Brockmeier, T.; López Mejía, D.I.; Sadakata, M.

    2015-01-01

    Music similarity is known to be a multi-dimensional concept, depending among others on rhythm similarity and timbre similarity. The present study aims to investigate whether such sub-dimensions of similarity can be assessed independently and how they relate to general similarity. To this end, we

  12. Transitions between beta and gamma rhythms in neural systems

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Setsinsky, D.; Fausbøll, Anders

    2002-01-01

    We study the coexistence of different rhythms in a local network of one inhibitory and two excitatory nerve cells for a wide range of the excitatory synapse strength and of the slow K+-channel conductance. The dynamic features of spike trains in the presence of noise are discussed. It is found...

  13. An analysis of rhythm in Japanese and English popular music

    NARCIS (Netherlands)

    Sadakata, M.; Desain, P.W.M.; Honing, H.J.; Patel, A.D.; Iversen, J.R.

    2003-01-01

    Recently, there has been evidence that the rhythm in English and French non-vocal musical themes are significantly different in their contrastiveness of successive durations in the same manner as those of spoken language, suggesting that acomposer's native language exerts an influence on the music

  14. Activity rhythms and distribution of natal dens for red foxes

    Science.gov (United States)

    Wenyang, Zhou; Wanhong, Wei; Biggins, Dean E.

    1995-01-01

    The red fox, Vulpes vulpes, was investigated with snow tracking, radiotracking and directive observation at the Haibei Research Station of Alpine Meadow Ecosystem, Academia Sinica, from March to September 1994. The objectives of this study were to determine the distribution and use of natal dens, activity rhythms, and home range sizes for the foxes.

  15. Tidal activity rhythms in the mangrove snail Cerithidea decollata ...

    African Journals Online (AJOL)

    Gastropoda: Prosobranchia: Cerithiidae). V.G. Cockcroft and A.T. Forbes. Department of Biological Sciences, University of Natal, Durban. Activity rhythms in Cerifhidea decol/afa which migrates be- tween the trees and the substrate in south-east ...

  16. Mood Disorders, Circadian Rhythms, Melatonin and Melatonin Agonists

    Directory of Open Access Journals (Sweden)

    M.A. Quera Salva

    2012-04-01

    Full Text Available Recent advances in the understanding of circadian rhythms have led to an interest in the treatment of major depressive disorder with chronobiotic agents. Many tissues have autonomous circadian rhythms, which are orchestrated by the master clock, situated in the suprachiasmatic nucleus (SNC. Melatonin (N-acetyl-5-hydroxytryptamine is secreted from the pineal gland during darkness. Melatonin acts mainly on MT1 and MT2 receptors, which are present in the SNC, regulating physiological and neuroendocrine functions, including circadian entrainment, referred to as the chronobiotic effet. Circadian rhythms has been shown to be either misaligned or phase shifted or decreased in amplitude in both acute episodes and relapse of major depressive disorder (MDD and bipolar disorder. Manipulation of circadian rhythms either using physical treatments (such as high intensity light or behavioral therapy has shown promise in improving symptoms. Pharmacotherapy using melatonin and pure melatonin receptor agonists, while improving sleep, has not been shown to improve symptoms of depression. A novel antidepressant, agomelatine, combines 5HT2c antagonist and melatonin agonist action, and has shown promise in both acute treatment of MDD and in preventing relapse.

  17. Cycles of Nature. An Introduction to Biological Rhythms.

    Science.gov (United States)

    Ahlgren, Andrew; Halberg, Franz

    This book is an outlined for the short study (1- to 2-weeks) of chronobiology, a field of science that explores the relationships between time and biological functions. It develops step-by-step the reasoning that leads to the current scientific understanding of biological rhythms. The unit can be inserted into a standard middle or high school…

  18. External stimuli mediate collective rhythms: artificial control strategies.

    Directory of Open Access Journals (Sweden)

    Tianshou Zhou

    Full Text Available The artificial intervention of biological rhythms remains an exciting challenge. Here, we proposed artificial control strategies that were developed to mediate the collective rhythms emerging in multicellular structures. Based on noisy repressilators and by injecting a periodic control amount to the extracellular medium, we introduced two typical kinds of control models. In one, there are information exchanges among cells, where signaling molecules receive the injected stimulus that freely diffuses toward/from the intercellular medium. In the other, there is no information exchange among cells, but signaling molecules also receive the stimulus that directionally diffuses into each cell from the common environment. We uncovered physical mechanisms for how the stimulus induces, enhances or ruins collective rhythms. We found that only when the extrinsic period is close to an integer multiplicity of the averaged intrinsic period can the collective behaviors be induced/enhanced; otherwise, the stimulus possibly ruins the achieved collective behaviors. Such entrainment properties of these oscillators to external signals would be exploited by realistic living cells to sense external signals. Our results not only provide a new perspective to the understanding of the interplays between extrinsic stimuli and intrinsic physiological rhythms, but also would lead to the development of medical therapies or devices.

  19. Transitions between beta and gamma rhythms in neural systems

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Setsinsky, D; Fausbøll, Anders

    2002-01-01

    We study the coexistence of different rhythms in a local network of one inhibitory and two excitatory nerve cells for a wide range of the excitatory synapse strength and of the slow K+-channel conductance. The dynamic features of spike trains in the presence of noise are discussed. It is found th...

  20. Studies on circadian rhythm disturbances and melatonin in delirium

    NARCIS (Netherlands)

    de Jonghe, A.-M.

    2014-01-01

    The circadian sleep/wake rhythm disturbances that are seen in delirium and the role of melatonin supplementation provide a new angle in delirium research. More research is needed to determine the role of melatonin in the pathophysiological mechanisms of delirium and to determine whether the

  1. The importance of hormonal circadian rhythms in daily feeding patterns

    NARCIS (Netherlands)

    Boumans, Iris J.M.M.; Boer, de Imke J.M.; Hofstede, Gert Jan; Fleur, la Susanne E.; Bokkers, Eddy

    2017-01-01

    The interaction between hormonal circadian rhythms and feeding behaviour is not well understood. This study aimed to deepen our understanding of mechanisms underlying circadian feeding behaviour in animals, using pigs, Sus scrofa, as a case study. Pigs show an alternans feeding pattern, that is,

  2. Integration of metabolic and cardiovascular diurnal rhythms by circadian clock.

    Science.gov (United States)

    Kohsaka, Akira; Waki, Hidefumi; Cui, He; Gouraud, Sabine S; Maeda, Masanobu

    2012-01-01

    Understanding how the 24-hour blood-pressure rhythm is programmed has been one of the most challenging questions in cardiovascular research. The 24-hour blood-pressure rhythm is primarily driven by the circadian clock system, in which the master circadian pacemaker within the suprachiasmatic nuclei of the hypothalamus is first entrained to the light/dark cycle and then transmits synchronizing signals to the peripheral clocks common to most tissues, including the heart and blood vessels. However, the circadian system is more complex than this basic hierarchical structure, as indicated by the discovery that peripheral clocks are either influenced to some degree or fully driven by temporal changes in energy homeostasis, independent of the light entrainment pathway. Through various comparative genomic approaches and through studies exploiting mouse genetics and transgenics, we now appreciate that cardiovascular tissues possess a large number of metabolic genes whose expression cycle and reciprocally affect the transcriptional control of major circadian clock genes. These findings indicate that metabolic cycles can directly or indirectly affect the diurnal rhythm of cardiovascular function. Here, we discuss a framework for understanding how the 24-hour blood-pressure rhythm is driven by the circadian system that integrates cardiovascular and metabolic function.

  3. Auditory and Visual Cues for Spatiotemporal Rhythm Reproduction

    DEFF Research Database (Denmark)

    Maculewicz, Justyna; Serafin, Stefania; Kofoed, Lise B.

    2013-01-01

    into account both temporal and spatial characteristics of the presented rhythmic sequences. We were particularly interested in inves- tigating temporal accuracy of the rhythm reproduction, correctness of the chosen signal location, and strength of pressure. We assumed to con- firm earlier findings stating...

  4. Listening to musical rhythms recruits motor regions of the brain.

    Science.gov (United States)

    Chen, Joyce L; Penhune, Virginia B; Zatorre, Robert J

    2008-12-01

    Perception and actions can be tightly coupled; but does a perceptual event dissociated from action processes still engage the motor system? We conducted 2 functional magnetic resonance imaging studies involving rhythm perception and production to address this question. In experiment 1, on each trial subjects 1st listened in anticipation of tapping, and then tapped along with musical rhythms. Recruitment of the supplementary motor area, mid-premotor cortex (PMC), and cerebellum was observed during listen with anticipation. To test whether this activation was related to motor planning or rehearsal, in experiment 2 subjects naively listened to rhythms without foreknowledge that they would later tap along with them. Yet, the same motor regions were engaged despite no action-perception connection. In contrast, the ventral PMC was only recruited during action and action-coupled perceptual processes, whereas the dorsal part was only sensitive to the selection of actions based on higher-order rules of temporal organization. These functional dissociations shed light on the nature of action-perception processes and suggest an inherent link between auditory and motor systems in the context of rhythm.

  5. Atrial Rate And Rhythm Abnormalities In A Patient With Hyperkalemia

    Directory of Open Access Journals (Sweden)

    Jonathan Rosman

    2009-05-01

    Full Text Available A 67 year old man presented with a serum potassium of 7.7 mEq/L and slow atrial flutter with variable A-V block and peaked T waves. Initial treatment for hyperkalemia was followed by an increase in the atrial flutter rate to 300 beats per minute. After hemodialysis the rhythm converted to sinus.

  6. Yoruba Oriki in English: Rhythm Analysis of Niyi Osundare's ...

    African Journals Online (AJOL)

    Toshiba

    Abstract. Rhythm is one major component that distinguishes poetry from prose, even in written forms. Being inherently based on rhyme, the indigenous sense and sound of oral poetry may be difficult to convey in written English. This study, therefore, investigated the prosody of. Niyi Osundare‟s “Harvestcall”, a praise poem ...

  7. Growth rhythms in sunflower (Helianthus annuus L.) in response to ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-04-12

    Apr 12, 2010 ... affect and modify plant attributes like growth, development and assimilation through physio-morphic functions, thus modifying plant ... and 2008) to document the effect of environmental variations on growth rhythms of sunflower hybrids. ..... temperature and maximum intercepted solar radiation at these crop ...

  8. Circadian activity rhythms in colonies of 'blind' molerats, Cryptomys ...

    African Journals Online (AJOL)

    1991-10-16

    Oct 16, 1991 ... Various activity rhythms (general, feeding, and toilet) were measured under controlled laboratory conditions in two colonies of the Damara molerat Cryptomys damarensis, for 140 consecutive days (following a 30 day test period) under various photoperiod regimes (16: 8 LD, 12: 12 LD, and constant dark ...

  9. Discrepancy between circadian rhythms of inulin and creatinine clearance

    NARCIS (Netherlands)

    van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; Krediet, R. T.; Arisz, L.

    1992-01-01

    To elucidate the disparity between circadian rhythmicity of inulin and creatinine clearance, we simultaneously measured inulin and creatinine clearances every 3 hours during 1 day in 14 normal subjects and in 8 patients with nephrotic syndrome. All patients and normal subjects had a circadian rhythm

  10. Perception of Timbre and Rhythm Similarity in Electronic Dance Music

    NARCIS (Netherlands)

    Honingh, A.; Panteli, M.; Brockmeier, T.; López Mejía, D.I.; Sadakata, M.

    2015-01-01

    Music similarity is known to be a multi-dimensional concept, depending among others on rhythm similarity and timbre similarity. The present study aims to investigate whether such sub-dimensions of similarity can be assessed independently and how they relate to general similarity. To this end, we

  11. Book Review: The ECG Atlas of Cardiac Rhythms | Doubell | South ...

    African Journals Online (AJOL)

    Book Title: The ECG Atlas of Cardiac Rhythms. Book Author: Rob Scott Millar. Cape Town: Clinics Cardive Publishing, 2015. ISBN: 978-0-620-64044-2. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL.

  12. Ultradian rhythm unmasked in the Pdf clock mutant of Drosophila

    Indian Academy of Sciences (India)

    2014-07-20

    Jul 20, 2014 ... from the mutation. As a result, Pdf01 mutant flies locomote with precise rhythmicity generated by one ultradian oscilla- tor. In future studies, we would like to dissect this system using genetic tools available in Drosophila, for example by silencing a particular set of Pdf-positive neurons. Circadian rhythms are ...

  13. Adaptive Significance of Circadian Rhythms-Biological Clocks and ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 1. Adaptive Significance of Circadian Rhythms - Biological Clocks and Darwinian Fitness in Cyanobacteria. V Sheeba Vijay Kumar Sharma Amitabh Joshi. Research News Volume 4 Issue 1 January 1999 pp 73-75 ...

  14. Circadian rhythms in liver metabolism and disease

    Directory of Open Access Journals (Sweden)

    Jessica M. Ferrell

    2015-03-01

    Full Text Available Mounting research evidence demonstrates a significant negative impact of circadian disruption on human health. Shift work, chronic jet lag and sleep disturbances are associated with increased incidence of metabolic syndrome, and consequently result in obesity, type 2 diabetes and dyslipidemia. Here, these associations are reviewed with respect to liver metabolism and disease.

  15. Social influences on circadian rhythms and sleep in insects.

    Science.gov (United States)

    Eban-Rothschild, Ada; Bloch, Guy

    2012-01-01

    The diverse social lifestyle and the small and accessible nervous system of insects make them valuable for research on the adaptive value and the organization principles of circadian rhythms and sleep. We focus on two complementary model insects, the fruit fly Drosophila melanogaster, which is amenable to extensive transgenic manipulations, and the honey bee Apis mellifera, which has rich and well-studied social behaviors. Social entrainment of activity rhythms (social synchronization) has been studied in many animals. Social time givers appear to be specifically important in dark cavity-dwelling social animals, but here there are no other clear relationships between the degree of sociality and the effectiveness of social entrainment. The olfactory system is important for social entrainment in insects. Little is known, however, about the molecular and neuronal pathways linking olfactory neurons to the central clock. In the honey bee, the expression, phase, and development of circadian rhythms are socially regulated, apparently by different signals. Peripheral clocks regulating pheromone synthesis and the olfactory system have been implicated in social influences on circadian rhythms in the fruit fly. An enriched social environment increases the total amount of sleep in both fruit flies and honey bees. In fruit flies, these changes have been linked to molecular and neuronal processes involved in learning, memory, and synaptic plasticity. The studies on insects suggest that social influences on the clock are richer than previously appreciated and have led to important breakthroughs in our understanding of the mechanisms underlying social influences on sleep and circadian rhythms. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. NREM Sleep Stage Transitions Control Ultradian REM Sleep Rhythm

    Science.gov (United States)

    Kishi, Akifumi; Yasuda, Hideaki; Matsumoto, Takahisa; Inami, Yasushi; Horiguchi, Jun; Tamaki, Masako; Struzik, Zbigniew R.; Yamamoto, Yoshiharu

    2011-01-01

    Study Objectives: The cyclic sequence of NREM and REM sleep, the so-called ultradian rhythm, is a highly characteristic feature of sleep. However, the mechanisms responsible for the ultradian REM sleep rhythm, particularly in humans, have not to date been fully elucidated. We hypothesize that a stage transition mechanism is involved in the determination of the ultradian REM sleep rhythm. Participants: Ten healthy young male volunteers (age: 22 ± 4 years, range 19–31 years) spent 3 nights in a sleep laboratory. The first was the adaptation night, and the second was the baseline night. On the third night, the subjects received risperidone (1 mg tablet), a central serotonergic and dopaminergic antagonist, 30 min before the polysomnography recording. Measurements and Results: We measured and investigated transition probabilities between waking, REM, and NREM sleep stages (N1, N2, and N3) within the REM-onset intervals, defined as the intervals between the onset of one REM period and the beginning of the next, altered by risperidone. We also calculated the transition intensity (i.e., instantaneous transition rate) and examined the temporal pattern of transitions within the altered REM-onset intervals. We found that when the REM-onset interval was prolonged by risperidone, the probability of transitions from N2 to N3 was significantly increased within the same prolonged interval, with a significant delay and/or recurrences of the peak intensity of transitions from N2 to N3. Conclusions: These results suggest that the mechanism governing NREM sleep stage transitions (from light to deep sleep) plays an important role in determining ultradian REM sleep rhythms. Citation: Kishi A; Yasuda H; Matsumoto T; Inami Y; Horiguchi J; Tamaki M; Struzik ZR; Yamamoto Y. NREM sleep stage transitions control ultradian REM sleep rhythm. SLEEP 2011;34(10):1423-1432. PMID:21966074

  17. 24-h monitoring devices and nyctohemeral rhythms of intraocular pressure.

    Science.gov (United States)

    Aptel, Florent; Weinreb, Robert N; Chiquet, Christophe; Mansouri, Kaweh

    2016-11-01

    Intraocular pressure (IOP) is not a fixed value and varies over both the short term and periods lasting several months or years. In particular, IOP is known to vary throughout the 24-h period of a day, defined as a nyctohemeral rhythm in humans. In clinical practice, it is crucial to evaluate the changes in IOP over 24 h in several situations, including the diagnosis of ocular hypertension and glaucoma (IOP is often higher at night) and to optimize the therapeutic management of glaucoma. Until recently, all evaluations of 24-h IOP rhythm were performed using repeated IOP measurements, requiring individuals to be awakened for nocturnal measurements. This method may be imperfect, because it is not physiologic and disturbs the sleep architecture, and also because it provides a limited number of time point measurements not sufficient to finely asses IOP changes. These limitations may have biased previous descriptions of physiological IOP rhythm. Recently, extraocular and intraocular devices integrating a pressure sensor for continuous IOP monitoring have been developed and are available for use in humans. The objective of this article is to present the contributions of these new 24-h monitoring devices for the study of the nyctohemeral rhythms. In healthy subjects and untreated glaucoma subjects, a nyctohemeral rhythm is consistently found and frequently characterized by a mean diurnal IOP lower than the mean nocturnal IOP, with a diurnal bathyphase - usually in the middle or at the end of the afternoon - and a nocturnal acrophase, usually in the middle or at the end of the night. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Rhythm and timing in autism: Learning to dance

    Directory of Open Access Journals (Sweden)

    Pat eAmos

    2013-04-01

    Full Text Available In recent years, a significant body of research has focused on challenges to neural connectivity as a key to understanding autism. In contrast to attempts to identify a single static, primarily brain-based deficit, children and adults diagnosed with autism are increasingly perceived as out of sync with their internal and external environments in dynamic ways that must also involve operations of the peripheral nervous systems. The noisiness that seems to occur in both directions of neural flow may help explain challenges to movement and sensing, and ultimately to entrainment with circadian rhythms and social interactions. across the autism spectrum. Profound differences in the rhythm and timing of movement have been tracked to infancy. Difficulties with self-synchrony inhibit praxis, and can disrupt the dance of relationships through which caregiver and child build meaning. Different sensory aspects of a situation may fail to match up; ultimately, intentions and actions themselves may be uncoupled. This uncoupling may help explain the expressions of alienation from the actions of one’s body which recur in the autobiographical autism literature. Multi-modal/cross-modal coordination of different types of sensory information into coherent events may be difficult to achieve because amodal properties (e.g. rhythm and tempo that help unite perceptions are unreliable. One question posed to the connectivity research concerns the role of rhythm and timing in this operation, and whether these can be mobilized to reduce overload and enhance performance. A case is made for developmental research addressing how people with autism actively explore and make sense of their environments. The parent/author recommends investigating approaches such as scaffolding interactions via rhythm, following the person’s lead, slowing the pace, discriminating between intentional communication and stray motor patterns, and organizing information through one sensory mode at

  19. Amplitude reduction and phase shifts of melatonin, cortisol and other circadian rhythms after a gradual advance of sleep and light exposure in humans.

    Science.gov (United States)

    Dijk, Derk-Jan; Duffy, Jeanne F; Silva, Edward J; Shanahan, Theresa L; Boivin, Diane B; Czeisler, Charles A

    2012-01-01

    The phase and amplitude of rhythms in physiology and behavior are generated by circadian oscillators and entrained to the 24-h day by exposure to the light-dark cycle and feedback from the sleep-wake cycle. The extent to which the phase and amplitude of multiple rhythms are similarly affected during altered timing of light exposure and the sleep-wake cycle has not been fully characterized. We assessed the phase and amplitude of the rhythms of melatonin, core body temperature, cortisol, alertness, performance and sleep after a perturbation of entrainment by a gradual advance of the sleep-wake schedule (10 h in 5 days) and associated light-dark cycle in 14 healthy men. The light-dark cycle consisted either of moderate intensity 'room' light (∼90-150 lux) or moderate light supplemented with bright light (∼10,000 lux) for 5 to 8 hours following sleep. After the advance of the sleep-wake schedule in moderate light, no significant advance of the melatonin rhythm was observed whereas, after bright light supplementation the phase advance was 8.1 h (SEM 0.7 h). Individual differences in phase shifts correlated across variables. The amplitude of the melatonin rhythm assessed under constant conditions was reduced after moderate light by 54% (17-94%) and after bright light by 52% (range 12-84%), as compared to the amplitude at baseline in the presence of a sleep-wake cycle. Individual differences in amplitude reduction of the melatonin rhythm correlated with the amplitude of body temperature, cortisol and alertness. Alterations in the timing of the sleep-wake cycle and associated bright or moderate light exposure can lead to changes in phase and reduction of circadian amplitude which are consistent across multiple variables but differ between individuals. These data have implications for our understanding of circadian organization and the negative health outcomes associated with shift-work, jet-lag and exposure to artificial light.

  20. Clock, Circadian Rhythms, and Breast Cancer

    National Research Council Canada - National Science Library

    Hill, Steven M

    2004-01-01

    .... Work involving circadian clock genes and cell cycle components suggests not only an association between the two time-keeping systems, but also regulation of the cell cycle by the circadian clock...

  1. The implicit learning of metrical and non-metrical rhythms in blind and sighted adults

    DEFF Research Database (Denmark)

    Carrara-Augustenborg, Claudia; Schultz, Benjamin G.

    2018-01-01

    mechanisms, few have examined whether blind individuals show a learning advantage for auditory rhythms and whether learning can occur unintentionally and without awareness, that is, implicitly. We compared blind to sighted controls in their ability to implicitly learn metrical and nonmetrical auditory...... predictions; the blind group learned nonmetrical rhythms more readily than the sighted group but the blind group learned metrical rhythms less readily than the sighted group. Only the sighted group learned metrical rhythms more readily than nonmetrical rhythms. The blind group demonstrated awareness...

  2. Movement-related theta rhythm in humans: coordinating self-directed hippocampal learning.

    Directory of Open Access Journals (Sweden)

    Raphael Kaplan

    Full Text Available The hippocampus is crucial for episodic or declarative memory and the theta rhythm has been implicated in mnemonic processing, but the functional contribution of theta to memory remains the subject of intense speculation. Recent evidence suggests that the hippocampus might function as a network hub for volitional learning. In contrast to human experiments, electrophysiological recordings in the hippocampus of behaving rodents are dominated by theta oscillations reflecting volitional movement, which has been linked to spatial exploration and encoding. This literature makes the surprising cross-species prediction that the human hippocampal theta rhythm supports memory by coordinating exploratory movements in the service of self-directed learning. We examined the links between theta, spatial exploration, and memory encoding by designing an interactive human spatial navigation paradigm combined with multimodal neuroimaging. We used both non-invasive whole-head Magnetoencephalography (MEG to look at theta oscillations and Functional Magnetic Resonance Imaging (fMRI to look at brain regions associated with volitional movement and learning. We found that theta power increases during the self-initiation of virtual movement, additionally correlating with subsequent memory performance and environmental familiarity. Performance-related hippocampal theta increases were observed during a static pre-navigation retrieval phase, where planning for subsequent navigation occurred. Furthermore, periods of the task showing movement-related theta increases showed decreased fMRI activity in the parahippocampus and increased activity in the hippocampus and other brain regions that strikingly overlap with the previously observed volitional learning network (the reverse pattern was seen for stationary periods. These fMRI changes also correlated with participant's performance. Our findings suggest that the human hippocampal theta rhythm supports memory by coordinating

  3. Simulated Night Shift Disrupts Circadian Rhythms of Immune Functions in Humans.

    Science.gov (United States)

    Cuesta, Marc; Boudreau, Philippe; Dubeau-Laramée, Geneviève; Cermakian, Nicolas; Boivin, Diane B

    2016-03-15

    Recent research unveiled a circadian regulation of the immune system in rodents, yet little is known about rhythms of immune functions in humans and how they are affected by circadian disruption. In this study, we assessed rhythms of cytokine secretion by immune cells and tested their response to simulated night shifts. PBMCs were collected from nine participants kept in constant posture over 24 h under a day-oriented schedule (baseline) and after 3 d under a night-oriented schedule. Monocytes and T lymphocytes were stimulated with LPS and PHA, respectively. At baseline, a bimodal rhythmic secretion was detected for IL-1β, IL-6, and TNF-α: a night peak was primarily due to a higher responsiveness of monocytes, and a day peak was partly due to a higher proportion of monocytes. A rhythmic release was also observed for IL-2 and IFN-γ, with a nighttime peak due to a higher cell count and responsiveness of T lymphocytes. Following night shifts, with the exception of IL-2, cytokine secretion was still rhythmic but with peak levels phase advanced by 4.5-6 h, whereas the rhythm in monocyte and T lymphocyte numbers was not shifted. This suggests distinct mechanisms of regulation between responsiveness to stimuli and cell numbers of the human immune system. Under a night-oriented schedule, only cytokine release was partly shifted in response to the change in the sleep-wake cycle. This led to a desynchronization of rhythmic immune parameters, which might contribute to the increased risk for infection, autoimmune diseases, cardiovascular and metabolic disorders, and cancer reported in shift workers. Copyright © 2016 by The American Association of Immunologists, Inc.

  4. Evaluation of the prognostic value of electrocardiography parameters and heart rhythm in patients with pulmonary hypertension.

    Science.gov (United States)

    Bandorski, Dirk; Bogossian, Harilaos; Ecke, Anja; Wiedenroth, Christoph; Gruenig, Ekkehard; Benjamin, Nicola; Arlt, Matthias; Seeger, Werner; Mayer, Eckhard; Ghofrani, Ardeschir; Hoeltgen, Reinhard; Gall, Henning

    2016-01-01

    Several studies have analyzed arrhythmias in patients with pulmonary hypertension (PH) and increased P-wave duration was identified as a risk factor for development of atrial fibrillation (AF). We retrospectively analyzed the incidence of arrhythmias in patients with an initial diagnosis of PH during long-term follow-up and assessed the prognostic value of electrocardiography (ECG) data. Data from 167 patients were analyzed (Dana Point Classification: Group 1: 59 patients, Group 2: 28 patients, Group 3: 39 patients, Group 4: 41 patients). Clinical, 6-min-ute walk distance test, echocardiography and right heart catheterization data were collected, and baseline/follow-up ECGs were analyzed. Baseline ECGs revealed sinus rhythm in 137 patients. Thirteen patients had newly onset AF during follow-up. In 30 patients, baseline ECG showed AF. Patients with baseline AF showed higher atrial diameters and higher right atrial pressure. Patients with P-wave du-ration > 0.11 s had shorter survival. Other ECG parameters (PQ-interval, QRS-width, QT-/ /QTc-interval) were not associated with survival. Mean survival times were 79.4 ± 5.4 months (sinus rhythm), 64.4 ± 12.9 months (baseline AF) and 58.8 ± 8.9 months (newly onset AF during follow-up) (p = 0.565). Atrial fibrillation predict adverse prognosis in patients with PH and a longer P-wave (> 0.11 s) is associated with shorter survival time.

  5. Improvement of Circadian Rhythm of Heart Rate Variability by Eurythmy Therapy Training

    Directory of Open Access Journals (Sweden)

    Georg Seifert

    2013-01-01

    Full Text Available Background. Impairment of circadian rhythm is associated with various clinical problems. It not only has a negative impact on quality of life but can also be associated with a significantly poorer prognosis. Eurythmy therapy (EYT is an anthroposophic movement therapy aimed at reducing fatigue symptoms and stress levels. Objective. This analysis of healthy subjects was conducted to examine whether the improvement in fatigue symptoms was accompanied by improvements in the circadian rhythm of heart rate variability (HRV. Design. Twenty-three women performed 10 hours of EYT over six weeks. Electrocardiograms (ECGs were recorded before and after the EYT trial. HRV was quantified by parameters of the frequency and time domains and the nonlinear parameters of symbolic dynamics. Results. The day-night contrast with predominance of vagal activity at night becomes more pronounced after the EYT training, and with decreased Ultralow and very low frequencies, the HRV shows evidence of calmer sleep. During the night, the complexity of the HRV is significantly increased indicated by nonlinear parameters. Conclusion. The analysis of the circadian patterns of cardiophysiological parameters before and after EYT shows significant improvements in HRV in terms of greater day-night contrast caused by an increase of vagal activity and calmer and more complex HRV patterns during sleep.

  6. Hypertension and Cardiac Arrhythmias

    DEFF Research Database (Denmark)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas

    2017-01-01

    Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation......, hypomagnesaemia), contributing further to arrhythmias, while effective Blood pressure control may prevent the development of the arrhythmias such as AF.In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC......) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence...

  7. Diurnal rhythms of spontaneous recurrent seizures and behavioral alterations of Wistar and spontaneously hypertensive rats in the kainate model of epilepsy.

    Science.gov (United States)

    Tchekalarova, Jane; Pechlivanova, Daniela; Itzev, Dimitar; Lazarov, Nikolai; Markova, Petya; Stoynev, Alexander

    2010-01-01

    Attention deficit hyperactivity disorder (ADHD) can coexist with epilepsy. Spontaneously hypertensive rats (SHRs) are considered to model ADHD with overactivity, impulsiveness, deficient sustained attention, and alterations in circadian autonomic profiles. The present study explored spontaneous recurrent seizures (SRSs) and behavioral diurnal activity rhythms in normotensive Wistar rats and SHRs in the kainate model of epilepsy. Rats were video monitored (24 h/3 months) to detect SRSs. SHRs manifested a lower seizure frequency during the light phase in the 8th and 10th weeks and a lower frequency of SRSs during the night phase accompanied by attenuated responses in hyperexcitability tests. Both epileptic strains were hyperactive, with lower anxiety levels, and their diurnal rhythms were abolished. Epileptic Wistar rats and SHRs exhibited less exploration during the dark phase. This study suggests that SHRs may be useful in modeling some aspects (particularly hypertension-related diurnal rhythm disturbance) of behavior associated with epilepsy. 2009 Elsevier Inc. All rights reserved.

  8. Treatment Failure With Rhythm and Rate Control Strategies in Patients With Atrial Fibrillation and Congestive Heart Failure: An AF-CHF Substudy.

    Science.gov (United States)

    Dyrda, Katia; Roy, Denis; Leduc, Hugues; Talajic, Mario; Stevenson, Lynne Warner; Guerra, Peter G; Andrade, Jason; Dubuc, Marc; Macle, Laurent; Thibault, Bernard; Rivard, Lena; Khairy, Paul

    2015-12-01

    Rate and rhythm control strategies for atrial fibrillation (AF) are not always effective or well tolerated in patients with congestive heart failure (CHF). We assessed reasons for treatment failure, associated characteristics, and effects on survival. A total of 1,376 patients enrolled in the AF-CHF trial were followed for 37  ±  19 months, 206 (15.0%) of whom failed initial therapy leading to crossover. Rhythm control was abandoned more frequently than rate control (21.0% vs. 9.1%, P CHF. The most common reasons for treatment failure are inefficacy for rhythm control and worsening heart failure for rate control. Changing strategies does not impact survival. © 2015 Wiley Periodicals, Inc.

  9. Diurnal and seasonal molecular rhythms in human neocortex and their relation to Alzheimer's disease.

    Science.gov (United States)

    Lim, Andrew S P; Klein, Hans-Ulrich; Yu, Lei; Chibnik, Lori B; Ali, Sanam; Xu, Jishu; Bennett, David A; De Jager, Philip L

    2017-04-03

    Circadian and seasonal rhythms are seen in many species, modulate several aspects of human physiology, including brain functions such as mood and cognition, and influence many neurological and psychiatric illnesses. However, there are few data regarding the genome-scale molecular correlates underlying these rhythms, especially in the human brain. Here, we report widespread, site-specific and interrelated diurnal and seasonal rhythms of gene expression in the human brain, and show their relationship with parallel rhythms of epigenetic modification including histone acetylation, and DNA methylation. We also identify transcription factor-binding sites that may drive these effects. Further, we demonstrate that Alzheimer's disease pathology disrupts these rhythms. These data suggest that interrelated diurnal and seasonal epigenetic and transcriptional rhythms may be an important feature of human brain biology, and perhaps human biology more broadly, and that changes in such rhythms may be consequences of, or contributors to, diseases such as Alzheimer's disease.

  10. Another place, another timer: Marine species and the rhythms of life.

    Science.gov (United States)

    Tessmar-Raible, Kristin; Raible, Florian; Arboleda, Enrique

    2011-03-01

    The marine ecosystem is governed by a multitude of environmental cycles, all of which are linked to the periodical recurrence of the sun or the moon. In accordance with these cycles, marine species exhibit a variety of biological rhythms, ranging from circadian and circatidal rhythms to circalunar and seasonal rhythms. However, our current molecular understanding of biological rhythms and clocks is largely restricted to solar-controlled circadian and seasonal rhythms in land model species. Here, we discuss the first molecular data emerging for circalunar and circatidal rhythms and present selected species suitable for further molecular analyses. We argue that a re-focus on marine species will be crucial to understand the principles, interactions and evolution of rhythms that govern a broad range of eukaryotes, including ourselves. Copyright © 2011 WILEY Periodicals, Inc.

  11. Physiology and regulation of biological rhythms in laboratory animals: an overview.

    Science.gov (United States)

    Wollnik, F

    1989-04-01

    Biological rhythms have been observed in practically all groups of laboratory mammals and at every level of physiological and behavioural organization. Biological rhythms are classified according to their period as ultradian (less than 24 h), circadian (approximately 24 h), infradian (greater than 24 h), and seasonal or circannual rhythms (approximately 1 year). This review outlines what is known about the neurobiology of biological rhythms in mammals and describes the hierarchical order in which ultradian, circadian and infradian rhythms are related to each other. The article does not attempt to catalogue every physiological variable showing rhythmical fluctuations in laboratory mammals. Rather, it focuses on the basic concepts of circadian rhythms and recent advances made in our understanding of the physiology of the internal clock controlling circadian and other biological rhythms.

  12. Got Rhythm? Get RockBand[TM]!

    Science.gov (United States)

    Nardo, Rachel

    2010-01-01

    According to a 2009 report by the Entertainment Software Association (ESA), at least 68% of American households now play video games, and half the parents in America now play video games with their children. Grandparents are in on the action, as well. In addition, nursing homes and senior centers are now incorporating video games into their…

  13. Sensory Feedback Interferes with Mu Rhythm Based Detection of Motor Commands from Electroencephalographic Signals

    Directory of Open Access Journals (Sweden)

    Maximilian Hommelsen

    2017-11-01

    Full Text Available Background: Electroencephalogram (EEG-based brain-computer interfaces (BCI represent a promising component of restorative motor therapies in individuals with partial paralysis. However, in those patients, sensory functions such as proprioception are at least partly preserved. The aim of this study was to investigate whether afferent feedback interferes with the BCI-based detection of efferent motor commands during execution of movements.Methods: Brain activity of 13 able-bodied subjects (age: 29.1 ± 4.8 years; 11 males was compared between a motor task (MT consisting of an isometric, isotonic grip and a somatosensory electrical stimulation (SS of the fingertips. Modulation of the mu rhythm (8–13 Hz was investigated to identify changes specifically related to the generation of efferent commands. A linear discriminant analysis (LDA was used to investigate the activation pattern on a single-trial basis. Classifiers were trained with MT vs. REST (periods without MT/SS and tested with SS and vice versa to quantify the impact of afferent feedback on the classification results.Results: Few differences in the spatial pattern between MT and SS were found in the modulation of the mu rhythm. All were characterized by event-related desynchronization (ERD peaks at electrodes C3, C4, and CP3. Execution of the MT was associated with a significantly stronger ERD in the majority of sensorimotor electrodes [C3 (p < 0.01; CP3 (p < 0.05; C4 (p < 0.01]. Classification accuracy of MT vs. REST was significantly higher than SS vs. REST (77% and 63%; p < 10-8. Classifiers trained on MT vs. REST were able to classify SS trials significantly above chance even though no motor commands were present during SS. Classifiers trained on SS performed better in classifying MT instead of SS.Conclusion: Our results challenge the notion that the modulation of the mu rhythm is a robust phenomenon for detecting efferent commands when afferent feedback is present. Instead, they

  14. Amiodarone for the maintenance of sinus rhythm in patients with atrial fibrillation.

    Science.gov (United States)

    Howard, P A

    1995-06-01

    To discuss the role of amiodarone for the maintenance of normal sinus rhythm in patients with atrial fibrillation (AF) and review the clinical trial data evaluating the efficacy and safety of amiodarone in patients with AF. A MEDLINE search was used to identify pertinent literature. Additional references were identified from the articles obtained in the search. Key search terms were atrial fibrillation, amiodarone, and sinus rhythm. All studies available at the time the article was prepared evaluating the efficacy and safety of amiodarone in AF were included. In addition, review articles discussing the role of amiodarone in AF were selected. No large, prospective, randomized trials have been performed. Data from 8 nonrandomized and 2 randomized trials are reported. Information derived from review articles is discussed. In patients with AF, maintenance of normal sinus rhythm is desirable to eliminate symptoms, improve functional capacity, and reduce the risk of thromboembolic complications. Class IA agents traditionally have been used; however, concerns about long-term effects on mortality have focused attention on other agents such as amiodarone. A number of nonrandomized, uncontrolled trials have found amiodarone to be effective for maintaining normal sinus rhythm in patients with AF that is refractory to conventional agents. Two randomized, nonblind trials have found amiodarone's efficacy to be equal to or superior to that of class IA drugs. The findings of these trials must be weighed, however, against the significant potential for toxicity and drug interactions associated with amiodarone. Cardiovascular toxicities, including proarrhythmic effects, appear to be relatively rare. In contrast, noncardiovascular effects are common and potentially serious. Although the preliminary data using amiodarone in AF are encouraging, many questions remain unanswered. Prospective, randomized trials are needed to evaluate the long-term efficacy and safety of amiodarone in

  15. The Biological Rhythms Interview of Assessment in Neuropsychiatry in patients with bipolar disorder: correlation with affective temperaments and schizotypy

    Directory of Open Access Journals (Sweden)

    Ewa Dopierala

    Full Text Available Objective: To assess the relationship of biological rhythms, evaluated by the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN, with affective temperaments and schizotypy. Methods: The BRIAN assessment, along with the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire (TEMPS-A and the Oxford-Liverpool Inventory for Feelings and Experiences (O-LIFE, was administered to 54 patients with remitted bipolar disorder (BD and 54 healthy control (HC subjects. Results: The TEMPS-A cyclothymic temperament correlated positively and the hyperthymic temperament correlated negatively with BRIAN scores in both the BD and HC groups, although the correlation was stronger in BD subjects. Depressive temperament was associated with BRIAN scores in BD but not in HC; conversely, the irritable temperament was associated with BRIAN scores in HC, but not in BD. Several positive correlations between BRIAN scores and the schizotypal dimensions of the O-LIFE were observed in both BD and HC subjects, especially with cognitive disorganization and less so with unusual experiences and impulsive nonconformity. A correlation with introversion/anhedonia was found only in BD subjects. Conclusion: Cyclothymic and depressive temperaments predispose to disturbances of biological rhythms in BD, while a hyperthymic temperament can be protective. Similar predispositions were also found for all schizotypal dimensions, mostly for cognitive disorganization.

  16. The Biological Rhythms Interview of Assessment in Neuropsychiatry in patients with bipolar disorder: correlation with affective temperaments and schizotypy.

    Science.gov (United States)

    Dopierala, Ewa; Chrobak, Adrian A; Kapczinski, Flavio; Michalak, Michal; Tereszko, Anna; Ferensztajn-Rochowiak, Ewa; Dudek, Dominika; Dembinska-Krajewska, Daria; Siwek, Marcin; Jaracz, Jan; Rybakowski, Janusz K

    2016-10-20

    To assess the relationship of biological rhythms, evaluated by the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN), with affective temperaments and schizotypy. The BRIAN assessment, along with the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire (TEMPS-A) and the Oxford-Liverpool Inventory for Feelings and Experiences (O-LIFE), was administered to 54 patients with remitted bipolar disorder (BD) and 54 healthy control (HC) subjects. The TEMPS-A cyclothymic temperament correlated positively and the hyperthymic temperament correlated negatively with BRIAN scores in both the BD and HC groups, although the correlation was stronger in BD subjects. Depressive temperament was associated with BRIAN scores in BD but not in HC; conversely, the irritable temperament was associated with BRIAN scores in HC, but not in BD. Several positive correlations between BRIAN scores and the schizotypal dimensions of the O-LIFE were observed in both BD and HC subjects, especially with cognitive disorganization and less so with unusual experiences and impulsive nonconformity. A correlation with introversion/anhedonia was found only in BD subjects. Cyclothymic and depressive temperaments predispose to disturbances of biological rhythms in BD, while a hyperthymic temperament can be protective. Similar predispositions were also found for all schizotypal dimensions, mostly for cognitive disorganization.

  17. Hericium erinaceus extracts alter behavioral rhythm in mice.

    Science.gov (United States)

    Furuta, Shoko; Kuwahara, Rika; Hiraki, Eri; Ohnuki, Koichiro; Yasuo, Shinobu; Shimizu, Kuniyoshi

    2016-01-01

    Hericium erinaceus (HE), an edible mushroom, has been used as a herbal medicine in several Asian countries since ancient times. HE has potential as a medicine for the treatment and prevention of dementia, a disorder closely linked with circadian rhythm. This study investigated the effects of the intake of HE extracts on behavioral rhythm, photosensitivity of the circadian clock, and clock gene mRNA expression in the suprachiasmatic nucleus (SCN), a central clock, in mice. Although the HE ethanol extract only affected the offset time of activity, the HE water extract advanced the sleep-wake cycle without affecting the free-running period, photosensitivity, or the clock gene mRNA expression in SCN. In addition, both extracts decreased wakefulness around end of active phase. The findings of the present study suggest that HE may serve as a functional food in the prevention and treatment of Alzheimer's disease and delayed sleep phase syndrome.

  18. Sleep, circadian rhythms, and the pathogenesis of Alzheimer disease.

    Science.gov (United States)

    Musiek, Erik S; Xiong, David D; Holtzman, David M

    2015-03-13

    Disturbances in the sleep-wake cycle and circadian rhythms are common symptoms of Alzheimer Disease (AD), and they have generally been considered as late consequences of the neurodegenerative processes. Recent evidence demonstrates that sleep-wake and circadian disruption often occur early in the course of the disease and may even precede the development of cognitive symptoms. Furthermore, the sleep-wake cycle appears to regulate levels of the pathogenic amyloid-beta peptide in the brain, and manipulating sleep can influence AD-related pathology in mouse models via multiple mechanisms. Finally, the circadian clock system, which controls the sleep-wake cycle and other diurnal oscillations in mice and humans, may also have a role in the neurodegenerative process. In this review, we examine the current literature related to the mechanisms by which sleep and circadian rhythms might impact AD pathogenesis, and we discuss potential therapeutic strategies targeting these systems for the prevention of AD.

  19. Spontaneous synchronized tapping to an auditory rhythm in a chimpanzee.

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2013-01-01

    Humans actively use behavioral synchrony such as dancing and singing when they intend to make affiliative relationships. Such advanced synchronous movement occurs even unconsciously when we hear rhythmically complex music. A foundation for this tendency may be an evolutionary adaptation for group living but evolutionary origins of human synchronous activity is unclear. Here we show the first evidence that a member of our closest living relatives, a chimpanzee, spontaneously synchronizes her movement with an auditory rhythm: After a training to tap illuminated keys on an electric keyboard, one chimpanzee spontaneously aligned her tapping with the sound when she heard an isochronous distractor sound. This result indicates that sensitivity to, and tendency toward synchronous movement with an auditory rhythm exist in chimpanzees, although humans may have expanded it to unique forms of auditory and visual communication during the course of human evolution.

  20. Wrist rhythm during wrist joint motion evaluated by dynamic radiography.

    Science.gov (United States)

    Kawashima, Hiroki; Tada, Kaoru; Suganuma, Seigo; Tsuchiya, Hiroyuki; Sanada, Shigeru

    2014-01-01

    We hypothesized that wrist joint motion involves a "wrist rhythm" similar to the scapulohumeral rhythm. Therefore, we used a flat-panel detector to evaluate the ratio of radiolunate and capitolunate joint motions during wrist joint motion by dynamic radiography. The subjects were 20 healthy men. Dynamic imaging of the wrist joint was performed during active exercise for a total of ten seconds. In this study, we defined the radiocarpal (RL angle) and midcarpal joint angle (CL angle) as the wrist joint angle in the obtained images and measured the variation of these angles. The average curve was plotted and regression lines calculated from the average curve. The ratio was calculated from the slopes of the regression lines of the RL CL angles. These findings indicated that the ratio of the RL and CL angle motions was approximately 1:4 during palmar flexion and approximately 2:1 during dorsiflexion.

  1. Alpha rhythm parameters and short-term memory span.

    Science.gov (United States)

    Maltseva, I V; Masloboev, Y P

    1997-06-01

    The study examined a statement from the neurophysiological model of A.N. Lebedev as to whether short-term memory span is related to a ratio of the alpha-rhythm frequency and parameters of step-type behaviour of wave processes in the EEG alpha range. Forty young healthy subjects performed a digit memory test. EEG signals were recorded from the occipital area during a resting period with eyes closed. As one of the parameters of step-type behaviour of alpha oscillations a mean value of the difference between periods of neighbouring peaks in the alpha spectra was calculated. A second parameter--the duration of alpha spindles, considered to be a superposition of alpha oscillations--was also measured. It was shown that the ratio of the alpha-rhythm frequency to parameters of the step-type behaviour of alpha oscillations positively correlated with memory performance.

  2. Musical genres: beating to the rhythms of different drums

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Debora C; Costa, Luciano da F [Instituto de Fisica de Sao Carlos - Universidade de Sao Paulo, Av. Trabalhador Sao Carlense 400, Caixa Postal 369, CEP 13560-970, Sao Carlos, Sao Paulo (Brazil); Saito, Jose H, E-mail: deboracorrea@ursa.ifsc.usp.b, E-mail: luciano@ursa.ifsc.usp.b [Departamento de Computacao-Universidade Federal de Sao Carlos, Rodovia Washington Luis, km 235, SP-310, CEP 13565-905, Sao Carlos, Sao Paulo (Brazil)

    2010-05-15

    Online music databases have increased significantly as a consequence of the rapid growth of the Internet and digital audio, requiring the development of faster and more efficient tools for music content analysis. Musical genres are widely used to organize music collections. In this paper, the problem of automatic single and multi-label music genre classification is addressed by exploring rhythm-based features obtained from a respective complex network representation. A Markov model is built in order to analyse the temporal sequence of rhythmic notation events. Feature analysis is performed by using two multivariate statistical approaches: principal components analysis (unsupervised) and linear discriminant analysis (supervised). Similarly, two classifiers are applied in order to identify the category of rhythms: parametric Bayesian classifier under the Gaussian hypothesis (supervised) and agglomerative hierarchical clustering (unsupervised). Qualitative results obtained by using the kappa coefficient and the obtained clusters corroborated the effectiveness of the proposed method.

  3. Musical genres: beating to the rhythms of different drums

    Science.gov (United States)

    Correa, Debora C.; Saito, Jose H.; Costa, Luciano da F.

    2010-05-01

    Online music databases have increased significantly as a consequence of the rapid growth of the Internet and digital audio, requiring the development of faster and more efficient tools for music content analysis. Musical genres are widely used to organize music collections. In this paper, the problem of automatic single and multi-label music genre classification is addressed by exploring rhythm-based features obtained from a respective complex network representation. A Markov model is built in order to analyse the temporal sequence of rhythmic notation events. Feature analysis is performed by using two multivariate statistical approaches: principal components analysis (unsupervised) and linear discriminant analysis (supervised). Similarly, two classifiers are applied in order to identify the category of rhythms: parametric Bayesian classifier under the Gaussian hypothesis (supervised) and agglomerative hierarchical clustering (unsupervised). Qualitative results obtained by using the kappa coefficient and the obtained clusters corroborated the effectiveness of the proposed method.

  4. QUANTIFYING ELONGATION RHYTHM DURING FULL-LENGTH PROTEIN SYNTHESIS

    Science.gov (United States)

    Rosenblum, Gabriel; Chen, Chunlai; Kaur, Jaskiran; Cui, Xiaonan; Zhang, Haibo; Asahara, Haruichi; Chong, Shaorong; Smilansky, Zeev; Goldman, Yale E.; Cooperman, Barry S.

    2013-01-01

    Pauses regulate the rhythm of ribosomal protein synthesis. Mutations disrupting even minor pauses can give rise to improperly formed proteins and human disease. Such minor pauses are difficult to characterize by ensemble methods, but can be readily examined by single-molecule (sm) approaches. Here we use smFRET to carry out real-time monitoring of the expression of a full-length protein, the green fluorescent protein variant Emerald GFP. We demonstrate significant correlations between measured elongation rates and codon and isoacceptor tRNA usage, and provide a quantitative estimate of the effect on elongation rate of replacing a codon recognizing an abundant tRNA with a synonymous codon cognate to a rarer tRNA. Our results suggest that tRNA selection plays an important general role in modulating the rates and rhythms of protein synthesis, potentially influencing simultaneous co-translational processes such as folding and chemical modification. PMID:23822614

  5. Circadian rhythms of chloroplast orientation and photosynthetic capacity in ulva.

    Science.gov (United States)

    Britz, S J; Briggs, W R

    1976-07-01

    Ulva lactuca L. var. latissima (L.) Decandolle and var. rigida (C. Agardh) Le Jolis and U. mutabilis Foyn have a circadian rhythm of chloroplast orientation which results in large changes in the light-absorption properties of the thallus. During the day, the chloroplasts cover the outer face of the cells and absorbance is high. At night, the chloroplasts are along the side walls and absorbance is low. Enteromorpha linza (L.) J. Agardh, E. intestinalis (L.) Link, E. sp., and Monostroma grevillei (Thuret) Wittrock, members of the Ulvales, were not observed to have this rhythmic movement. Chloroplasts, when in the face position, could not be induced to move to the sides by high intensity light up to 80,000 lux. Unrelated to chloroplast position per se and light-absorption efficiency, there is a rhythm of photosynthetic capacity which peaks just before midday and which continues in constant darkness.

  6. Music and speech prosody: A common rhythm

    OpenAIRE

    Maija eHausen; Ritva eTorppa; Salmela, Viljami R.; Martti eVainio; Teppo eSärkämö

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosod...

  7. Music and speech prosody: a common rhythm

    OpenAIRE

    Hausen, Maija; Torppa, Ritva; Salmela, Viljami R.; Vainio, Martti; Särkämö, Teppo

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosod...

  8. Circadian rhythms in bed rest: Monitoring core body temperature via heat-flux approach is superior to skin surface temperature.

    Science.gov (United States)

    Mendt, Stefan; Maggioni, Martina Anna; Nordine, Michael; Steinach, Mathias; Opatz, Oliver; Belavý, Daniel; Felsenberg, Dieter; Koch, Jochim; Shang, Peng; Gunga, Hanns-Christian; Stahn, Alexander

    2017-01-01

    Continuous recordings of core body temperature (CBT) are a well-established approach in describing circadian rhythms. Given the discomfort of invasive CBT measurement techniques, the use of skin temperature recordings has been proposed as a surrogate. More recently, we proposed a heat-flux approach (the so-called Double Sensor) for monitoring CBT. Studies investigating the reliability of the heat-flux approach over a 24-hour period, as well as comparisons with skin temperature recordings, are however lacking. The first aim of the study was therefore to compare rectal, skin, and heat-flux temperature recordings for monitoring circadian rhythm. In addition, to assess the optimal placement of sensor probes, we also investigated the effect of different anatomical measurement sites, i.e. sensor probes positioned at the forehead vs. the sternum. Data were collected as part of the Berlin BedRest study (BBR2-2) under controlled, standardized, and thermoneutral conditions. 24-hours temperature data of seven healthy males were collected after 50 days of -6° head-down tilt bed-rest. Mean Pearson correlation coefficients indicated a high association between rectal and forehead temperature recordings (r > 0.80 for skin and Double Sensor). In contrast, only a poor to moderate relationship was observed for sensors positioned at the sternum (r = -0.02 and r = 0.52 for skin and Double Sensor, respectively). Cross-correlation analyses further confirmed the feasibility of the forehead as a preferred monitoring site. The phase difference between forehead Double Sensor and rectal recordings was not statistically different from zero (p = 0.313), and was significantly smaller than the phase difference between forehead skin and rectal temperatures (p = 0.016). These findings were substantiated by cosinor analyses, revealing significant differences for mesor, amplitude, and acrophase between rectal and forehead skin temperature recordings, but not between forehead Double Sensor and rectal

  9. O2 uptake and blood pressure regulation at the onset of exercise: interaction of circadian rhythm and priming exercise.

    Science.gov (United States)

    Faisal, Azmy; Beavers, Keith R; Hughson, Richard L

    2010-12-01

    Circadian rhythm has an influence on several physiological functions that contribute to athletic performance. We tested the hypothesis that circadian rhythm would affect blood pressure (BP) responses but not O(2) uptake (Vo(2)) kinetics during the transitions to moderate and heavy cycling exercises. Nine male athletes (peak Vo(2): 60.5 ± 3.2 ml·kg(-1)·min(-1)) performed multiple rides of two different cycling protocols involving sequences of 6-min bouts at moderate or heavy intensities interspersed by a 20-W baseline in the morning (7 AM) and evening (5 PM). Breath-by-breath Vo(2) and beat-by-beat BP estimated by finger cuff plethysmography were measured simultaneously throughout the protocols. Circadian rhythm did not affect Vo(2) onset kinetics determined from the phase II time constant (τ(2)) during either moderate or heavy exercise bouts with no prior priming exercise (τ(2) moderate exercise: morning 22.5 ± 4.6 s vs. evening 22.2 ± 4.6 s and τ(2) heavy exercise: morning 26.0 ± 2.7 s vs. evening 26.2 ± 2.6 s, P > 0.05). Priming exercise induced the same robust acceleration in Vo(2) kinetics during subsequent moderate and heavy exercise in the morning and evening. A novel finding was an overshoot in BP (estimated from finger cuff plethysmography) in the first minutes of each moderate and heavy exercise bout. After the initial overshoot, BP declined in association with increased skin blood flow between the third and sixth minute of the exercise bout. Priming exercise showed a greater effect in modulating the BP responses in the evening. These findings suggest that circadian rhythm interacts with priming exercise to lower BP during exercise after an initial overshoot with a greater influence in the evening associated with increased skin blood flow.

  10. Chorusing, synchrony and the evolutionary functions of rhythm

    Directory of Open Access Journals (Sweden)

    Andrea eRavignani

    2014-10-01

    Full Text Available A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc. with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony, we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, making group behavior key to understand the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates. Finally, we propose an Evolving Signal Timing hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s of rhythmic behavior in our proto-musical primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and

  11. Photoperiodic Influences on Ultradian Rhythms of Male Siberian Hamsters

    Science.gov (United States)

    Prendergast, Brian J.; Zucker, Irving

    2012-01-01

    Seasonal changes in mammalian physiology and behavior are proximately controlled by the annual variation in day length. Long summer and short winter day lengths markedly alter the amplitude of endogenous circadian rhythms and may affect ultradian oscillations, but the threshold photoperiods for inducing these changes are not known. We assessed the effects of short and intermediate day lengths and changes in reproductive physiology on circadian and ultradian rhythms of locomotor activity in Siberian hamsters. Males were maintained in a long photoperiod from birth (15 h light/day; 15 L) and transferred in adulthood to 1 of 7 experimental photoperiods ranging from 14 L to 9 L. Decreases in circadian rhythm (CR) robustness, mesor and amplitude were evident in photoperiods ≤14 L, as were delays in the timing of CR acrophase and expansion of nocturnal activity duration. Nocturnal ultradian rhythms (URs) were comparably prevalent in all day lengths, but 15 L markedly inhibited the expression of light-phase URs. The period (τ’), amplitude and complexity of URs increased in day lengths ≤13 L. Among hamsters that failed to undergo gonadal regression in short day lengths (nonresponders), τ’ of the dark-phase UR was longer than in photoresponsive hamsters; in 13 L the incidence and amplitude of light-phase URs were greater in hamsters that did not undergo testicular regression. Day lengths as long as 14 L were sufficient to trigger changes in the waveform of CRs without affecting UR waveform. The transition from a long- to a short-day ultradian phenotype occurred for most UR components at day lengths of 12 L–13 L, thereby establishing different thresholds for CR and UR responses to day length. At the UR-threshold photoperiod of 13 L, differences in gonadal status were largely without effect on most UR parameters. PMID:22848579

  12. Lucky Rhythms in Orbitofrontal Cortex Bias Gambling Decisions in Humans

    OpenAIRE

    Sacr?,