Read by QxMD icon Read

Heart muscle contraction

Zhanna Kobalava
The burden of cardiovascular diseases (CVD) in general and heart failure (HF) in particular continues to increase worldwide. CVD are major contributors to death and morbidity and recognized as important drivers of healthcare expenditure. Chronic overactivity of the renin-angiotensin-aldosterone system (RAAS) plays a key role in human hypertension and HF pathophysiology. RAAS is fundamental in the overall regulation of cardiovascular homeostasis through the actions of hormones, which regulate vascular tone, and specifically blood pressure through vasoconstriction and renal sodium and water retention...
September 2016: Journal of Hypertension
M Hirschvogel, M Bassilious, L Jagschies, S M Wildhirt, M W Gee
A model for patient-specific cardiac mechanics simulation is introduced, incorporating a 3-dimensional finite element model of the ventricular part of the heart which is coupled to a reduced-order 0-dimensional closed-loop vascular system, heart valve and atrial chamber model.The ventricles are modeled by a nonlinear orthotropic passive material law. The electrical activation is mimicked by a prescribed parametrized active stress acting along a generic muscle fiber orientation. Our activation function is constructed such that the start of ventricular contraction and relaxation as well as the active stress curve's slope are parameterized...
October 15, 2016: International Journal for Numerical Methods in Biomedical Engineering
Amy E Mendham, Rob Duffield, Aaron J Coutts, Frank E Marino, Andriy Boyko, Andrew J McAinch, David John Bishop
PURPOSE: This study assessed the mitochondrial related signaling responses to a single bout of non-contact, modified football (touch rugby), played as small-sided games (SSG), or cycling (CYC) exercise in sedentary, obese, middle-aged men. METHOD: In a randomized, cross-over design, nine middle-aged, sedentary, obese men completed two, 40-min exercise conditions (CYC and SSG) separated by a 21-d recovery period. Heart rate (HR) and Ratings of Perceived Exertion were collected during each bout...
October 14, 2016: Journal of Applied Physiology
Marcin Kunecki, Wojciech Płazak, Tomasz Roleder, Jolanta Biernat, Tomasz Oleksy, Piotr Podolec, Krzysztof Stanisław Gołba
BACKGROUND: Ischemic preconditioning (IPC) and postconditioning (POC) are the novel strategies of attaining cardioprotection against ischemia/reperfusion (I/R) injury. Previous studies suggested the role of opioid pathway, however the class of opioid receptors responsible for this effect in humans remains unknown. The aim of the study was to assess the influence of opioids on simulated I/R injury outcomes in the human myocardium. METHODS: Trabeculae of the human right atrium were electrically driven in organ bath and subjected to simulated I/R injury...
October 13, 2016: Cardiology Journal
Daniel A Hernandez, Christina M Bennett, Lyubov Dunina-Barkovskaya, Tatjana Wedig, Yassemi Capetanaki, Harald Herrmann, Gloria M Conover
In the hearts of patients bearing nebulette mutations, a severe general disorganization in cardiomyocytes of the extrasarcomeric desmin intermediate filament system is frequently observed. However, the molecular and functional relationship between the desmin cytoskeleton and nebulette-containing sarcomeres is still unclear. Here we report a high-affinity in vitro interaction between nebulette and desmin filaments. A major interaction site has been mapped to the desmin α-helical rod domain indicating that the filament core is directly involved in the binding of nebulette...
October 12, 2016: Molecular Biology of the Cell
Ann P Quick, Qiongling Wang, Leonne E Philippen, Giselle Barreto-Torres, David Y Chiang, David L Beavers, Guoliang Wang, Maha Khalid, Julia O Reynolds, Hannah M Campbell, Jordan Showell, Mark D McCauley, Arjen Scholten, Xander H Wehrens
RATIONALE: Junctional membrane complexes (JMC) in myocytes are critical microdomains, in which excitation-contraction coupling occurs. Structural and functional disruption of JMCs underlies contractile dysfunction in failing hearts. However, the role of newly identified JMC protein striated muscle preferentially expressed gene (SPEG) remains unclear. OBJECTIVE: To determine the role of SPEG in healthy and failing adult hearts. MMethods and Results: Proteomic analysis of immunoprecipatated JMC-proteins ryanodine receptor type-2 (RyR2) and junctophilin-2 (JPH2) followed by mass spectrometry identified the serine-threonine kinase SPEG as the only novel binding partner for both proteins...
October 11, 2016: Circulation Research
Steven B Marston
Mutations in striated muscle contractile proteins have been found to be the cause of a number of inherited muscle diseases; in most cases the mechanism proposed for causing the disease is derangement of the thin filament-based Ca(2+)-regulatory system of the muscle. When considering the results of experiments reported over the last 15 years, one feature has been frequently noted, but rarely discussed: the magnitude of changes in myofilament Ca(2+)-sensitivity due to myopathy-causing mutations in skeletal or heart muscle seems to be always in the range 1...
2016: Frontiers in Physiology
Akira Hanashima, Ken Hashimoto, Yoshihiro Ujihara, Takeshi Honda, Tomoko Yobimoto, Aya Kodama, Satoshi Mohri
Connectin, also called titin, is the largest protein with a critical function as a molecular spring during contraction and relaxation of striated muscle; its mutation leads to severe myopathy and cardiomyopathy. To uncover the cause of this pathogenesis, zebrafish have recently been used as disease models because they are easier to genetically modify than mice. Although the gene structures and putative primary structures of zebrafish connectin have been determined, the actual primary structures of zebrafish connectin in heart and skeletal muscles remain unclear because of its large size and the PCR amplification-associated difficulties...
October 7, 2016: Gene
Hanting Yang, Miaohui Hu, Jianli Guo, Xiaomin Ou, Tanxi Cai, Zhenfeng Liu
Intracellular Ca(2+) signalling processes are fundamental to muscle contraction, neurotransmitter release, cell growth and apoptosis. Release of Ca(2+) from the intracellular stores is supported by a series of ion channels in sarcoplasmic or endoplasmic reticulum (SR/ER). Among them, two isoforms of the trimeric intracellular cation (TRIC) channel family, named TRIC-A and TRIC-B, modulate the release of Ca(2+) through the ryanodine receptor or inositol triphosphate receptor, and maintain the homeostasis of ions within SR/ER lumen...
October 3, 2016: Nature
Luis Peñailillo, Nicolás Guzmán, José Cangas, Alvaro Reyes, Hermann Zbinden-Foncea
: The aim of this study was to examine the metabolic demand and extent of muscle damage of eccentric cycling targeting knee flexor (FLEX) and knee extensor (EXT) muscles. METHODS: Eight sedentary men (23.3 ± 0.7 y) underwent two eccentric cycling sessions (EXT and FLEX) of 30 min each, at 60% of the maximum power output. Oxygen consumption (VO2), heart rate (HR) and rated perceived exertion (RPE) were measured during cycling. Countermovement and squat jumps (CMJ and SJ), muscle flexibility, muscle soreness and pain pressure threshold (PPT) of knee extensor and flexor muscles were measured before, immediately after and 1-4 days after cycling...
August 15, 2016: European Journal of Sport Science
Ian M Robertson, Sandra E Pineda-Sanabria, Ziqian Yan, Thomas Kampourakis, Yin-Biao Sun, Brian D Sykes, Malcolm Irving
The binding of Ca(2+) to cardiac troponin C (cTnC) triggers contraction in heart muscle. In the diseased heart, the myocardium is often desensitized to Ca(2+), which leads to impaired contractility. Therefore, compounds that sensitize cardiac muscle to Ca(2+) (Ca(2+)-sensitizers) have therapeutic promise. The only Ca(2+)-sensitizer used regularly in clinical settings is levosimendan. While the primary target of levosimendan is thought to be cTnC, the molecular details of this interaction are not well understood...
October 17, 2016: Biochemistry
Pim van der Harst, Jessica van Setten, Niek Verweij, Georg Vogler, Lude Franke, Matthew T Maurano, Xinchen Wang, Irene Mateo Leach, Mark Eijgelsheim, Nona Sotoodehnia, Caroline Hayward, Rossella Sorice, Osorio Meirelles, Leo-Pekka Lyytikäinen, Ozren Polašek, Toshiko Tanaka, Dan E Arking, Sheila Ulivi, Stella Trompet, Martina Müller-Nurasyid, Albert V Smith, Marcus Dörr, Kathleen F Kerr, Jared W Magnani, Fabiola Del Greco M, Weihua Zhang, Ilja M Nolte, Claudia T Silva, Sandosh Padmanabhan, Vinicius Tragante, Tõnu Esko, Gonçalo R Abecasis, Michiel E Adriaens, Karl Andersen, Phil Barnett, Joshua C Bis, Rolf Bodmer, Brendan M Buckley, Harry Campbell, Megan V Cannon, Aravinda Chakravarti, Lin Y Chen, Alessandro Delitala, Richard B Devereux, Pieter A Doevendans, Anna F Dominiczak, Luigi Ferrucci, Ian Ford, Christian Gieger, Tamara B Harris, Eric Haugen, Matthias Heinig, Dena G Hernandez, Hans L Hillege, Joel N Hirschhorn, Albert Hofman, Norbert Hubner, Shih-Jen Hwang, Annamaria Iorio, Mika Kähönen, Manolis Kellis, Ivana Kolcic, Ishminder K Kooner, Jaspal S Kooner, Jan A Kors, Edward G Lakatta, Kasper Lage, Lenore J Launer, Daniel Levy, Alicia Lundby, Peter W Macfarlane, Dalit May, Thomas Meitinger, Andres Metspalu, Stefania Nappo, Silvia Naitza, Shane Neph, Alex S Nord, Teresa Nutile, Peter M Okin, Jesper V Olsen, Ben A Oostra, Josef M Penninger, Len A Pennacchio, Tune H Pers, Siegfried Perz, Annette Peters, Yigal M Pinto, Arne Pfeufer, Maria Grazia Pilia, Peter P Pramstaller, Bram P Prins, Olli T Raitakari, Soumya Raychaudhuri, Ken M Rice, Elizabeth J Rossin, Jerome I Rotter, Sebastian Schafer, David Schlessinger, Carsten O Schmidt, Jobanpreet Sehmi, Herman H W Silljé, Gianfranco Sinagra, Moritz F Sinner, Kamil Slowikowski, Elsayed Z Soliman, Timothy D Spector, Wilko Spiering, John A Stamatoyannopoulos, Ronald P Stolk, Konstantin Strauch, Sian-Tsung Tan, Kirill V Tarasov, Bosco Trinh, Andre G Uitterlinden, Malou van den Boogaard, Cornelia M van Duijn, Wiek H van Gilst, Jorma S Viikari, Peter M Visscher, Veronique Vitart, Uwe Völker, Melanie Waldenberger, Christian X Weichenberger, Harm-Jan Westra, Cisca Wijmenga, Bruce H Wolffenbuttel, Jian Yang, Connie R Bezzina, Patricia B Munroe, Harold Snieder, Alan F Wright, Igor Rudan, Laurie A Boyer, Folkert W Asselbergs, Dirk J van Veldhuisen, Bruno H Stricker, Bruce M Psaty, Marina Ciullo, Serena Sanna, Terho Lehtimäki, James F Wilson, Stefania Bandinelli, Alvaro Alonso, Paolo Gasparini, J Wouter Jukema, Stefan Kääb, Vilmundur Gudnason, Stephan B Felix, Susan R Heckbert, Rudolf A de Boer, Christopher Newton-Cheh, Andrew A Hicks, John C Chambers, Yalda Jamshidi, Axel Visel, Vincent M Christoffels, Aaron Isaacs, Nilesh J Samani, Paul I W de Bakker
BACKGROUND: Myocardial mass is a key determinant of cardiac muscle function and hypertrophy. Myocardial depolarization leading to cardiac muscle contraction is reflected by the amplitude and duration of the QRS complex on the electrocardiogram (ECG). Abnormal QRS amplitude or duration reflect changes in myocardial mass and conduction, and are associated with increased risk of heart failure and death. OBJECTIVES: This meta-analysis sought to gain insights into the genetic determinants of myocardial mass...
September 27, 2016: Journal of the American College of Cardiology
Zhanna Kobalava
The burden of cardiovascular diseases (CVD) in general and heart failure (HF) in particular continues to increase worldwide. CVD are major contributors to death and morbidity and recognized as important drivers of healthcare expenditure. Chronic overactivity of the renin-angiotensin-aldosterone system (RAAS) plays a key role in human hypertension and HF pathophysiology. RAAS is fundamental in the overall regulation of cardiovascular homeostasis through the actions of hormones, which regulate vascular tone, and specifically blood pressure through vasoconstriction and renal sodium and water retention...
September 2016: Journal of Hypertension
Michael Habeck, Elmira Tokhtaeva, Yotam Nadav, Efrat Ben Zeev, Sean P Ferris, Randal J Kaufman, Elizabeta Bab-Dinitz, Jack H Kaplan, Laura A Dada, Zvi Farfel, Daniel M Tal, Adriana Katz, George Sachs, Olga Vagin, Steven J D Karlish
The Na,K-ATPase 2 subunit plays a key role in cardiac muscle contraction by regulating intracellular Ca2+ while α1 has a more conventional role of maintaining ion homeostasis. The β subunit differentially regulates maturation, trafficking and activity of α-β heterodimers. It is not known whether the distinct role of α2 in heart is related to selective assembly with a particular one of the three β isoforms. We show here by immunofluorescence and co-immunoprecipitation that α2 is preferentially expressed with β2 in T-tubules of cardiac myocytes, forming α2β2 heterodimers...
September 13, 2016: Journal of Biological Chemistry
Haibin Gong, Yanfei Li, Lei Wang, Qian Lv, Xiuli Wang
The study was conducted to examine the effects of ICI 118,551 on the systolic function of cardiac muscle cells of rats in heart failure and determine the molecular mechanism of selective β2-adrenergic receptor (β2-AR) antagonist on these cells. The chronic heart failure model for rats was prepared through abdominal aortic constriction and separate cardiac muscle cells using the collagenase digestion method. The rats were then divided into Sham, HF and HF+ICI 50 nM goups and cultivated for 48 h. β2-AR, Gi/Gs and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a) protein expression levels in the cardiac muscle cells were evaluated by western blotting and changes in the systolic function of cardiac muscle cells based on the boundary detection system of contraction dynamics for individual cells was measured...
September 2016: Experimental and Therapeutic Medicine
Sam L Teichman, Kassandra S Thomson, Michael Regnier
Chronic inotropic therapy is effective for the treatment of heart failure with reduced ejection fraction, but has been limited by adverse long-term safety profiles, development of tolerance, and the need for chronic parenteral administration. A safe and convenient therapeutic agent that produces sustained inotropic effects could improve symptoms, functional capacity, and quality of life. Small amounts of 2-deoxy-adenosine triphosphate (dATP) activate cardiac myosin leading to enhanced contractility in normal and failing heart muscle...
September 3, 2016: Handbook of Experimental Pharmacology
Xu-Fang Bai, Amy X Ma
Both right and left ventricles are developed from two adjacent segments of the primary heart tube. Though they are different with regard to shape and power, they mirror each other in terms of behavior. This is the first level of symmetry in cardiac function assessment. Both cardiac muscle contraction and relaxation are active. This constructs the second level of symmetry in cardiac function assessment. Combination of the two levels will help to find some hidden indexes or approaches to evaluate cardiac function...
September 2016: Journal of Geriatric Cardiology: JGC
Md Shenuarin Bhuiyan, Patrick McLendon, Jeanne James, Hanna Osinska, James Gulick, Bidur Bhandary, John N Lorenz, Jeffrey Robbins
Cardiac myosin-binding protein C (cMyBP-C) is an integral part of the sarcomeric machinery in cardiac muscle that enables normal function. cMyBP-C regulates normal cardiac contraction by functioning as a brake through interactions with the sarcomere's thick, thin, and titin filaments. cMyBP-C's precise effects as it binds to the different filament systems remain obscure, particularly as it impacts on the myosin heavy chain's head domain, contained within the subfragment 2 (S2) region. This portion of the myosin heavy chain also contains the ATPase activity critical for myosin's function...
October 2016: Pflügers Archiv: European Journal of Physiology
Benjamin P Woodall, Meryl C Woodall, Timothy S Luongo, Laurel A Grisanti, Douglas G Tilley, John W Elrod, Walter J Koch
GRK2, a G protein-coupled receptor kinase, plays a critical role in cardiac physiology. Adrenergic receptors are the primary target for GRK2 activity in the heart; phosphorylation by GRK2 leads to desensitization of these receptors. As such, levels of GRK2 activity in the heart directly correlate with cardiac contractile function. Furthermore, increased expression of GRK2 after cardiac insult exacerbates injury and speeds progression to heart failure. Despite the importance of this kinase in both the physiology and pathophysiology of the heart, relatively little is known about the role of GRK2 in skeletal muscle function and disease...
October 14, 2016: Journal of Biological Chemistry
Yuzhi Jia, Hsiang-Chun Chang, Matthew J Schipma, Jing Liu, Varsha Shete, Ning Liu, Tatsuya Sato, Edward B Thorp, Philip M Barger, Yi-Jun Zhu, Navin Viswakarma, Yashpal S Kanwar, Hossein Ardehali, Bayar Thimmapaya, Janardan K Reddy
Mediator, an evolutionarily conserved multi-protein complex consisting of about 30 subunits, is a key component of the polymerase II mediated gene transcription. Germline deletion of the Mediator subunit 1 (Med1) of the Mediator in mice results in mid-gestational embryonic lethality with developmental impairment of multiple organs including heart. Here we show that cardiomyocyte-specific deletion of Med1 in mice (csMed1-/-) during late gestational and early postnatal development by intercrossing Med1fl/fl mice to α-MyHC-Cre transgenic mice results in lethality within 10 days after weaning due to dilated cardiomyopathy-related ventricular dilation and heart failure...
2016: PloS One
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"