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Sample records for single heart muscle

  1. Is the Fundamental Electrical Response of the Single Heart Muscle Cell a Spike Potential?

    Science.gov (United States)

    Churney, Leon; Ohshima, Hisashi

    1963-01-01

    The urodele amphibians, Amphiuma and Necturus, provide heart fibers large enough to serve for microelectrode recording under visual control with the microscope. Bundles containing as few as 5 to 10 fibers yield spike potentials, rather than the plateau forms generally considered to be characteristic of heart muscle. These spikes fail to overshoot. The plateau form, and only the plateau form, is recorded exclusively from large tissue masses. An intermingling of spikes and plateau-shaped action potentials is obtained from bundles of intermediate size. These data are confirmed in experiments in which the myocardium is sliced into adhering strips of unequal sizes. The conclusion is drawn that the configuration of the recorded action potential curve is contingent upon the mass and geometry of the tissue impaled by the microelectrode. The crucial experiment of recording from an isolated single heart fiber is not possible, because of the attendant injury. Our proposal that the spike form is the elemental heart action potential is, to this extent, an extrapolation. Attempts to explain the nature of the spike along classical lines are not entirely satisfactory. Other theories are considered which, in their turn, are generally unacceptable. Evidently only further experimentation can clarify the situation. PMID:14021260

  2. Making more heart muscle

    NARCIS (Netherlands)

    van den Hoff, Maurice J. B.; Kruithof, Boudewijn P. T.; Moorman, Antoon F. M.

    2004-01-01

    Postnatally, heart muscle cells almost completely lose their ability to divide, which makes their loss after trauma irreversible. Potential repair by cell grafting or mobilizing endogenous cells is of particular interest for possible treatments for heart disease, where the poor capacity for

  3. Action potential-evoked calcium release is impaired in single skeletal muscle fibers from heart failure patients.

    Directory of Open Access Journals (Sweden)

    Marino DiFranco

    Full Text Available Exercise intolerance in chronic heart failure (HF has been attributed to abnormalities of the skeletal muscles. Muscle function depends on intact excitation-contraction coupling (ECC, but ECC studies in HF models have been inconclusive, due to deficiencies in the animal models and tools used to measure calcium (Ca2+ release, mandating investigations in skeletal muscle from HF patients. The purpose of this study was to test the hypothesis that Ca2+ release is significantly impaired in the skeletal muscle of HF patients in whom exercise capacity is severely diminished compared to age-matched healthy volunteers.Using state-of-the-art electrophysiological and optical techniques in single muscle fibers from biopsies of the locomotive vastus lateralis muscle, we measured the action potential (AP-evoked Ca2+ release in 4 HF patients and 4 age-matched healthy controls. The mean peak Ca2+ release flux in fibers obtained from HF patients (10±1.2 µM/ms was markedly (2.6-fold and significantly (p<0.05 smaller than in fibers from healthy volunteers (28±3.3 µM/ms. This impairment in AP-evoked Ca2+ release was ubiquitous and was not explained by differences in the excitability mechanisms since single APs were indistinguishable between HF patients and healthy volunteers.These findings prove the feasibility of performing electrophysiological experiments in single fibers from human skeletal muscle, and offer a new approach for investigations of myopathies due to HF and other diseases. Importantly, we have demonstrated that one step in the ECC process, AP-evoked Ca2+ release, is impaired in single muscle fibers in HF patients.

  4. Kinetics of a single cross-bridge in familial hypertrophic cardiomyopathy heart muscle measured by reverse Kretschmann fluorescence

    Science.gov (United States)

    Mettikolla, Prasad; Calander, Nils; Luchowski, Rafal; Gryczynski, Ignacy; Gryczynski, Zygmunt; Borejdo, Julian

    2010-01-01

    Familial hypertrophic cardiomyopathy (FHC) is a serious heart disease that often leads to a sudden cardiac death of young athletes. It is believed that the alteration of the kinetics of interaction between actin and myosin causes FHC by making the heart to pump blood inefficiently. We set out to check this hypothesis ex vivo. During contraction of heart muscle, a myosin cross-bridge imparts periodic force impulses to actin. The impulses are analyzed by fluorescence correlation spectroscopy (FCS) of fluorescently labeled actin. To minimize observation volume and background fluorescence, we carry out FCS measurements in surface plasmon coupled emission mode in a reverse Kretschmann configuration. Fluorescence is a result of near-field coupling of fluorophores excited in the vicinity of the metal-coated surface of a coverslip with the surface plasmons propagating in the metal. Surface plasmons decouple on opposite sides of the metal film and emit in a directional manner as far-field p-polarized radiation. We show that the rate of changes of orientation is significantly faster in contracting cardiac myofibrils of transgenic mice than wild type. These results are consistent with the fact that mutated heart muscle myosin translates actin faster in in vitro motility assays.

  5. The acute effects of a single session of expiratory muscle strength training on blood pressure, heart rate, and oxygen saturation in healthy adults.

    Science.gov (United States)

    Laciuga, Helena; Davenport, Paul; Sapienza, Christine

    2012-01-01

    Expiratory muscle strength training (EMST) is a rehabilitative program that has been tested for outcomes related to respiratory muscle strength, cough, swallow, and voice function in healthy young adult, elderly individuals, and in patients with progressive neurodegenerative disease. Because EMST has been used in patient care, the associated cardiovascular responses during EMST are of importance. This study investigated the changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and oxygen saturation (SpO(2)) during one session of EMST in healthy, young adults as a preliminary study of device safety. Thirty-one participants completed a single session of 25 trials with the EMST device. Valsalva maneuvers were performed at the beginning and at the end of the EMST trials for task comparison. The SBP, DBP, HR, and SpO(2) were recorded at the baseline and after completing the following tasks: a Valsalva maneuver, 12 trials using the EMST device, 13 trials using the EMST device, and 5 min of rest following the EMST session. A mixed linear model tested for changes across the six time points. The results indicated no significant change of SBP, DBP, HR, or SpO(2) during or following the EMST trials or after performing the Valsalva maneuver. The results suggest that EMST does not elicit significant fluctuations of blood pressure, HR, and SpO(2) in healthy young adults even when considering the effects of covariates on the outcomes measures.

  6. Muscle size explains low passive skeletal muscle force in heart failure patients.

    Science.gov (United States)

    Panizzolo, Fausto Antonio; Maiorana, Andrew J; Naylor, Louise H; Dembo, Lawrence G; Lloyd, David G; Green, Daniel J; Rubenson, Jonas

    2016-01-01

    Alterations in skeletal muscle function and architecture have been linked to the compromised exercise capacity characterizing chronic heart failure (CHF). However, how passive skeletal muscle force is affected in CHF is not clear. Understanding passive force characteristics in CHF can help further elucidate the extent to which altered contractile properties and/or architecture might affect muscle and locomotor function. Therefore, the aim of this study was to investigate passive force in a single muscle for which non-invasive measures of muscle size and estimates of fiber force are possible, the soleus (SOL), both in CHF patients and age- and physical activity-matched control participants. Passive SOL muscle force and size were obtained by means of a novel approach combining experimental data (dynamometry, electromyography, ultrasound imaging) with a musculoskeletal model. We found reduced passive SOL forces (∼30%) (at the same relative levels of muscle stretch) in CHF vs. healthy individuals. This difference was eliminated when force was normalized by physiological cross sectional area, indicating that reduced force output may be most strongly associated with muscle size. Nevertheless, passive force was significantly higher in CHF at a given absolute muscle length (non length-normalized) and likely explained by the shorter muscle slack lengths and optimal muscle lengths measured in CHF compared to the control participants. This later factor may lead to altered performance of the SOL in functional tasks such gait. These findings suggest introducing exercise rehabilitation targeting muscle hypertrophy and, specifically for the calf muscles, exercise that promotes muscle lengthening.

  7. Embryogenesis of the heart muscle

    Czech Academy of Sciences Publication Activity Database

    Sedmera, David; McQuinn, T. C.

    2008-01-01

    Roč. 4, - (2008), s. 235-245 ISSN 1551-7136 Grant - others:National Institutes of Health(US) C06 RR16434; National Institutes of Health(US) C06 RR018823; AV ČR(CZ) Purkyně Fellowship Institutional research plan: CEZ:AV0Z5045916 Keywords : heart development * myocardium * microscopy Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  8. Muscle size explains low passive skeletal muscle force in heart failure patients

    Directory of Open Access Journals (Sweden)

    Fausto Antonio Panizzolo

    2016-09-01

    Full Text Available Background Alterations in skeletal muscle function and architecture have been linked to the compromised exercise capacity characterizing chronic heart failure (CHF. However, how passive skeletal muscle force is affected in CHF is not clear. Understanding passive force characteristics in CHF can help further elucidate the extent to which altered contractile properties and/or architecture might affect muscle and locomotor function. Therefore, the aim of this study was to investigate passive force in a single muscle for which non-invasive measures of muscle size and estimates of fiber force are possible, the soleus (SOL, both in CHF patients and age- and physical activity-matched control participants. Methods Passive SOL muscle force and size were obtained by means of a novel approach combining experimental data (dynamometry, electromyography, ultrasound imaging with a musculoskeletal model. Results We found reduced passive SOL forces (∼30% (at the same relative levels of muscle stretch in CHF vs. healthy individuals. This difference was eliminated when force was normalized by physiological cross sectional area, indicating that reduced force output may be most strongly associated with muscle size. Nevertheless, passive force was significantly higher in CHF at a given absolute muscle length (non length-normalized and likely explained by the shorter muscle slack lengths and optimal muscle lengths measured in CHF compared to the control participants. This later factor may lead to altered performance of the SOL in functional tasks such gait. Discussion These findings suggest introducing exercise rehabilitation targeting muscle hypertrophy and, specifically for the calf muscles, exercise that promotes muscle lengthening.

  9. [Expression of the dignity of organs: the heart, a muscle].

    Science.gov (United States)

    Hildebrand, Reinhard

    2004-02-01

    As the muscular nature of the heart had been recognized and it had become evident that the heart was nothing but a hollow muscle, it lost its position as the centre of man. This became likewise true for its position within the body studied with anatomical and physiological methods as with the notion of the heart being an organ of sensibility, emotions, intellect, and will revealed in a particular "heart language". The dignity of the heart assigned to it from ancient time was treated with contempt as a but empty phrase. When, however, in the various attempts to study its myocardial architecture its highly sophisticated engeneering became evident, the real marvel of the heart was demonstrated engendering even in men and women of science an "element of aesthetic awe". Thus, in a certain sense, the heart has recovered its dignity.

  10. Muscle force compensation among synergistic muscles after fatigue of a single muscle.

    Science.gov (United States)

    Stutzig, Norman; Siebert, Tobias

    2015-08-01

    The aim of this study was to examine control strategies among synergistic muscles after fatigue of a single muscle. It was hypothesized that the compensating mechanism is specific for each fatigued muscle. The soleus (SOL), gastrocnemius lateralis (GL) and medialis (GM) were fatigued in separate sessions on different days. In each experiment, subjects (n = 11) performed maximal voluntary contractions prior to and after fatiguing a single muscle (SOL, GL or GM) while the voluntary muscle activity and torque were measured. Additionally, the maximal single twitch torque of the plantarflexors and the maximal spinal reflex activity (H-reflex) of the SOL, GL and GM were determined. Fatigue was evoked using neuromuscular stimulation. Following fatigue the single twitch torque decreased by -20.1%, -19.5%, and -23.0% when the SOL, GL, or GM, have been fatigued. The maximal voluntary torque did not decrease in any session but the synergistic voluntary muscle activity increased significantly. Moreover, we found no alterations in spinal reflex activity. It is concluded that synergistic muscles compensate each other. Furthermore, it seems that self-compensating mechanism of the fatigued muscles occurred additionally. The force compensation does not depend on the function of the fatigued muscle. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

    International Nuclear Information System (INIS)

    Nawrath, H.; Raschack, M.

    1987-01-01

    (-)-Desmethoxyverapamil [also known as (-)-devapamil or (-)-D888] has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and 45 Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and 45 Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle

  12. Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

    Energy Technology Data Exchange (ETDEWEB)

    Nawrath, H.; Raschack, M.

    1987-09-01

    (-)-Desmethoxyverapamil (also known as (-)-devapamil or (-)-D888) has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and /sup 45/Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and /sup 45/Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle.

  13. Muscle metaboreflex and autonomic regulation of heart rate in humans

    DEFF Research Database (Denmark)

    Fisher, James P; Adlan, Ahmed M; Shantsila, Alena

    2013-01-01

    We elucidated the autonomic mechanisms whereby heart rate (HR) is regulated by the muscle metaboreflex. Eight male participants (22 ± 3 years) performed three exercise protocols: (1) enhanced metaboreflex activation with partial flow restriction (bi-lateral thigh cuff inflation) during leg cycling...

  14. Muscle metaboreflex-induced vasoconstriction in the ischemic active muscle is exaggerated in heart failure.

    Science.gov (United States)

    Kaur, Jasdeep; Senador, Danielle; Krishnan, Abhinav C; Hanna, Hanna W; Alvarez, Alberto; Machado, Tiago M; O'Leary, Donal S

    2018-01-01

    When oxygen delivery to active muscle is insufficient to meet the metabolic demand during exercise, metabolites accumulate and stimulate skeletal muscle afferents, inducing a reflex increase in blood pressure, termed the muscle metaboreflex. In healthy individuals, muscle metaboreflex activation (MMA) during submaximal exercise increases arterial pressure primarily via an increase in cardiac output (CO), as little peripheral vasoconstriction occurs. This increase in CO partially restores blood flow to ischemic muscle. However, we recently demonstrated that MMA induces sympathetic vasoconstriction in ischemic active muscle, limiting the ability of the metaboreflex to restore blood flow. In heart failure (HF), increases in CO are limited, and metaboreflex-induced pressor responses occur predominantly via peripheral vasoconstriction. In the present study, we tested the hypothesis that vasoconstriction of ischemic active muscle is exaggerated in HF. Changes in hindlimb vascular resistance [femoral arterial pressure ÷ hindlimb blood flow (HLBF)] were observed during MMA (via graded reductions in HLBF) during mild exercise with and without α 1 -adrenergic blockade (prazosin, 50 µg/kg) before and after induction of HF. In normal animals, initial HLBF reductions caused metabolic vasodilation, while reductions below the metaboreflex threshold elicited reflex vasoconstriction, in ischemic active skeletal muscle, which was abolished after α 1 -adrenergic blockade. Metaboreflex-induced vasoconstriction of ischemic active muscle was exaggerated after induction of HF. This heightened vasoconstriction impairs the ability of the metaboreflex to restore blood flow to ischemic muscle in HF and may contribute to the exercise intolerance observed in these patients. We conclude that sympathetically mediated vasoconstriction of ischemic active muscle during MMA is exaggerated in HF. NEW & NOTEWORTHY We found that muscle metaboreflex-induced vasoconstriction of the ischemic active

  15. Effects of inspiratory muscle training in patients with heart failure.

    Science.gov (United States)

    Bosnak-Guclu, Meral; Arikan, Hulya; Savci, Sema; Inal-Ince, Deniz; Tulumen, Erol; Aytemir, Kudret; Tokgözoglu, Lale

    2011-11-01

    To investigate the effects of inspiratory muscle training (IMT) on functional capacity and balance, respiratory and peripheral muscle strength, pulmonary function, dyspnea, fatigue, depression, and quality of life in heart failure patients. A prospective, randomized controlled, double-blinded study. Thirty patients with heart failure (NYHA II-III, LVEFdepression were evaluated. Functional capacity and balance, respiratory and peripheral muscle strength, dyspnea, depression were significantly improved in the treatment group compared with controls; quality of life and fatigue were similarly improved within groups (p cmH(2)O, p depression (11.47 ± 7.50 to 3.20 ± 4.09, p cmH(2)O, p = 0.001), FVC%, depression (14.36 ± 9.04 to 9.50 ± 10.42, p = 0.011), quality of life and fatigue (42.86 ± 12.67 to 32.93 ± 15.87, p = 0.008) were significantly improved in the control group. The IMT improves functional capacity and balance, respiratory and peripheral muscle strength; decreases depression and dyspnea perception in patients with heart failure. IMT should be included effectively in pulmonary rehabilitation programs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Tissue specific phosphorylation of mitochondrial proteins isolated from rat liver, heart muscle, and skeletal muscle

    DEFF Research Database (Denmark)

    Bak, Steffen; León, Ileana R; Jensen, Ole Nørregaard

    2013-01-01

    of TiO2 phosphopeptide-enrichment, HILIC fractionation, and LC-MS/MS on isolated mitochondria to investigate the tissue-specific mitochondrial phosphoproteomes of rat liver, heart, and skeletal muscle. In total, we identified 899 phosphorylation sites in 354 different mitochondrial proteins including......Phosphorylation of mitochondrial proteins in a variety of biological processes is increasingly being recognized and may contribute to the differences in function and energy demands observed in mitochondria from different tissues such as liver, heart, and skeletal muscle. Here, we used a combination...

  17. Coming full circle: membrane potential, sarcolemmal calcium influx and excitation-contraction coupling in heart muscle.

    Science.gov (United States)

    Hobai, I A; Levi, A J

    1999-12-01

    In heart muscle, strong evidence shows that excitation-contraction coupling involves Ca-induced Ca-release. However, under some conditions, single heart cells show Ca release and contraction which is not correlated with Ca entry via the Ca channel, suggesting a second Ca-independent release mechanism. Similar observations were made in early, pioneering studies using voltage-clamped multi-cellular preparations. We review the influence that experimental preparations and conditions have had on excitation-contraction coupling theory over the last 20 years.

  18. Correlation of the severity of diabetic retinopathy and the heart muscle perfusion in patients with type 2 diabetes.

    Science.gov (United States)

    Tryniszewski, Wiesław; Kuśmierczyk, Jarosław; Maziarz, Zbigniew; Goś, Roman; Mikhailidis, Dimitri P; Banach, Maciej; Rysz, Jacek; Pesudovs, Konrad

    2011-01-01

    The objective was to investigate whether microvascular disturbances in patients with type 2 diabetes (DM) as defined by retinal examination predict the existence of macrovascular disturbances found on radioisotopic perfusion examinations of the heart muscle. A total of 100 patients with type 2 DM and an additional cardiovascular risk factor were enrolled in the study. All patients underwent comprehensive ophthalmologic examination, including fundus color photography and fluorescein angiography, and were divided into three groups: group 1 (NoDR): met the inclusion criteria but had no diabetic retinopathy; group 2 (NPDR): had signs of nonproliferative diabetic retinopathy; group 3 (PDR): had signs of preproliferative or proliferative diabetic retinopathy. After collecting general medical history and clinical data, patients underwent heart muscle perfusion studies. All patients followed a 48-h protocol heart muscle perfusion examination in the rest state as well as after the standardized exercise test. Single photon emission computed tomography examination was performed. In the PDR group, the impairment of the heart muscle perfusion at stress and rest was more frequent than in the NPDR and NoDR groups. Analysis of the heart muscle perfusion results for the three groups showed a significant relationship with the severity of microvascular complications observed in eye fundus examinations. Comprehensive ophthalmologic assessment of the progression of diabetic retinopathy in patients with type 2 DM may be an indicator of heart muscle perfusion disturbance. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. The mechanisms of muscle wasting in COPD and heart failure

    Directory of Open Access Journals (Sweden)

    Giorgio Vescovo

    2012-10-01

    Full Text Available Many of the mechanisms leading to skeletal muscle wasting in COPD and heart failure are common to both conditions. These encompass neurohormonal activation and systemic inflammation. The mechanisms leading to muscle dysfunction are both qualitative and quantitative. Qualitative changes comprise the transition from aerobic metabolism and prevalent slow fibers composition toward anaerobic metabolism and fast fibers synthesis. Quantitative changes are mainly linked to muscle loss. These changes occur not only in the major muscles bulks of the body but also in respiratory muscles. The mechanisms leading to muscle wastage include cytokine-triggered skeletal muscle apoptosis and ubiquitin-proteasomeand non-ubiquitin-dependent pathways. The regulation of fiber type involves the growth hormone/insulin-like growth factor 1/calcineurin/transcriptional coactivator PGC1 cascade. The imbalance between protein synthesis and degradation plays an important role. Protein degradation can occur through ubiquitin-dependent and non-ubiquitin-dependent pathways. Very recently, two systems controlling ubiquitin-proteasome activation have been described: FOXO-ubiquitin ligase and NFkB ubiquitin ligase. These are triggered by TNFα and growth hormone/insulin-like growth factor 1. Moreover, apoptosis, which is triggered by tumor necrosis factor α, plays an important role. Another mechanism acting on muscle wastage is malnutrition, with an imbalance between catabolic and anabolic factors toward the catabolic component. Catabolism is also worsened by the activation of the adrenergic system and alteration of the cortisol/DEHA ratio toward cortisol production. Sarcomeric protein oxidation and its consequent contractile impairment can be another cause of skeletal muscle dysfunction in CHF.

  20. Physiological roles of taurine in heart and muscle

    OpenAIRE

    Schaffer, Stephen W; Ju Jong, Chian; KC, Ramila; Azuma, Junichi

    2010-01-01

    Taurine (aminoethane sulfonic acid) is an ubiquitous compound, found in very high concentrations in heart and muscle. Although taurine is classified as an amino acid, it does not participate in peptide bond formation. Nonetheless, the amino group of taurine is involved in a number of important conjugation reactions as well as in the scavenging of hypochlorous acid. Because taurine is a fairly inert compound, it is an ideal modulator of basic processes, such as osmotic pressure, cation homeost...

  1. Mechanical stimulation in the engineering of heart muscle.

    Science.gov (United States)

    Liaw, Norman Yu; Zimmermann, Wolfram-Hubertus

    2016-01-15

    Recreating the beating heart in the laboratory continues to be a formidable bioengineering challenge. The fundamental feature of the heart is its pumping action, requiring considerable mechanical forces to compress a blood filled chamber with a defined in- and outlet. Ventricular output crucially depends on venous loading of the ventricles (preload) and on the force generated by the preloaded ventricles to overcome arterial blood pressure (afterload). The rate of contraction is controlled by the spontaneously active sinus node and transmission of its electrical impulses into the ventricles. The underlying principles for these physiological processes are described by the Frank-Starling mechanism and Bowditch phenomenon. It is essential to consider these principles in the design and evaluation of tissue engineered myocardium. This review focuses on current strategies to evoke mechanical loading in hydrogel-based heart muscle engineering. Copyright © 2015. Published by Elsevier B.V.

  2. Characterizing rapid-onset vasodilation to single muscle contractions in the human leg

    Science.gov (United States)

    Credeur, Daniel P.; Holwerda, Seth W.; Restaino, Robert M.; King, Phillip M.; Crutcher, Kiera L.; Laughlin, M. Harold; Padilla, Jaume

    2014-01-01

    Rapid-onset vasodilation (ROV) following single muscle contractions has been examined in the forearm of humans, but has not yet been characterized in the leg. Given known vascular differences between the arm and leg, we sought to characterize ROV following single muscle contractions in the leg. Sixteen healthy men performed random ordered single contractions at 5, 10, 20, 40, and 60% of their maximum voluntary contraction (MVC) using isometric knee extension made with the leg above and below heart level, and these were compared with single isometric contractions of the forearm (handgrip). Single thigh cuff compressions (300 mmHg) were utilized to estimate the mechanical contribution to leg ROV. Continuous blood flow was determined by duplex-Doppler ultrasound and blood pressure via finger photoplethysmography (Finometer). Single isometric knee extensor contractions produced intensity-dependent increases in peak leg vascular conductance that were significantly greater than the forearm in both the above- and below-heart level positions (e.g., above heart level: leg 20% MVC, +138 ± 28% vs. arm 20% MVC, +89 ± 17%; P leg. Collectively, these data demonstrate the presence of a rapid and robust vasodilation to single muscle contractions in the leg that is largely independent of mechanical factors, thus establishing the leg as a viable model to study ROV in humans. PMID:25539935

  3. Intercostal and forearm muscle deoxygenation during respiratory fatigue in patients with heart failure: potential role of a respiratory muscle metaboreflex.

    Science.gov (United States)

    Moreno, A M; Castro, R R T; Silva, B M; Villacorta, H; Sant'Anna Junior, M; Nóbrega, A C L

    2014-11-01

    The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66 ± 12 years; left ventricle ejection fraction, 34 ± 3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1 ± 1.3 min in heart failure patients and at 9.3 ± 1.4 min in controls (P0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (Pmuscles (heart failure, -4.5 ± 0.5%; controls, +0.5 ± 0.8%; Pfatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.

  4. THE STUDY OF HEART MUSCLE IN CHRONIC ALCOHOLICS

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    Girish M

    2016-09-01

    Full Text Available BACKGROUND Alcohol affects many organs, especially the liver, pancreas and brain. Although, the beneficial effects of mild or moderate ethanol consumption have been implied with respect to coronary artery disease, excessive ethanol consumption can result in Alcoholic Heart Muscle Disease (AHMD. AIMS Alcohol consumption, mainly arrack, is common social problem in Mangalore. This study has been undertaken to assess the effects of alcohol on cardiovascular system. MATERIALS AND METHODS Thirty patient with history of consumption of about 6 units of alcohol per day for at least 5 days a week for at least 5 years who were admitted to Government Wenlock Hospital, Attavar K.M.C. and University Medical Centre, Mangalore, were selected as case and studied. RESULTS Alcohol intake is predominantly observed in males, majority of alcoholic had high blood pressure, serum levels of CPK-MB and LDH are elevated in chronic alcoholic patients, left ventricular hypertrophy, premature ventricular contraction and sinus tachycardia were common findings in the electrocardiograms of chronic alcoholic patients and development of alcoholic heart muscle disease is directly proportional to the quantity and duration of alcohol intake. CONCLUSION Overall, the present study has found high morbidity from chronic alcohol consumption highlighting the need for preventive measures to tackle this preventable hazard.

  5. Single Muscle Fiber Proteomics Reveals Fiber-Type-Specific Features of Human Muscle Aging

    Directory of Open Access Journals (Sweden)

    Marta Murgia

    2017-06-01

    Full Text Available Skeletal muscle is a key tissue in human aging, which affects different muscle fiber types unequally. We developed a highly sensitive single muscle fiber proteomics workflow to study human aging and show that the senescence of slow and fast muscle fibers is characterized by diverging metabolic and protein quality control adaptations. Whereas mitochondrial content declines with aging in both fiber types, glycolysis and glycogen metabolism are upregulated in slow but downregulated in fast muscle fibers. Aging mitochondria decrease expression of the redox enzyme monoamine oxidase A. Slow fibers upregulate a subset of actin and myosin chaperones, whereas an opposite change happens in fast fibers. These changes in metabolism and sarcomere quality control may be related to the ability of slow, but not fast, muscle fibers to maintain their mass during aging. We conclude that single muscle fiber analysis by proteomics can elucidate pathophysiology in a sub-type-specific manner.

  6. Deriving muscle fiber diameter from recorded single fiber potential.

    Science.gov (United States)

    Zalewska, Ewa

    2017-12-01

    The aim of the study was to estimate muscle fiber diameters through analysis of single muscle fiber potentials (SFPs) recorded in the frontalis muscle of a healthy subject. Our previously developed analytical and graphic method to derive fiber diameter from the analysis of the negative peak duration and the amplitude of SFP, was applied to a sample of ten SFPs recorded in vivo. Muscle fiber diameters derived from the simulation method for the sample of frontalis muscle SFPs are consistent with anatomical data for this muscle. The results confirm the utility of proposed simulation method. Outlying data could be considered as the result of a contribution of other fibers to the potential recorded using an SFEMG electrode. Our graphic tool provides a rapid estimation of muscle fiber diameter. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. The contribution of inspiratory muscles function to exercise limitation in heart failure: pathophysiological mechanisms

    OpenAIRE

    Ribeiro,Jorge P.; Chiappa,Gaspar R.; Callegaro,Carine C.

    2012-01-01

    BACKGROUND: Heart failure induces histological, metabolic and functional adaptations in the inspiratory muscles. This inspiratory muscle weakness, which occurs in 30% to 50% of the heart failure patients, is associated with reduction in the functional capacity, reduction in the quality of life and with a poor prognosis in these individuals. OBJECTIVES: The objective of this review was to discuss the pathophysiological mechanisms that may explain the role of the inspiratory muscles in the exer...

  8. Pengaruh Immediet Instrumental Music Hearing Therapy Dengan Progresive Muscle Relaxation Exercise Terhadap Rest Heart Reat

    OpenAIRE

    Trisnowiyanto, Bambang

    2015-01-01

    Objective: to know the immediate effect of listening to music (instrumental music hearing therapy) and muscle relaxation exercises (progressive muscle relaxation exercise) to the resting pulse rate.Background: the number of heartbeats in one minute, which gives a clear picture of the load when the activity of the heart muscle is needed at a particular time. The heart rate can be affected by physical exercise and a good atmosphere to listen to music.Subject: students of junior high school were...

  9. Congenital heart disease in adolescents with gluteal muscle contracture.

    Science.gov (United States)

    You, Tian; Zhang, Xin-tao; Zha, Zhen-gang; Zhang, Wen-tao

    2015-02-01

    Gluteal muscle contracture (GMC), presented with hip abduction and external rotation when crouching, is common in several ethnicities, particularly in Chinese. It remains unclear that the reasons why these children are weak and have no choice to accept repeated intramuscular injection. Here, we found some unique cases which may be useful to explain this question. We describe a series of special GMC patients, who are accompanied with congenital heart disease (CHD). These cases were first observed in preoperative examinations of a patient with atrial septal defect (ASD), which was proved by chest X-ray and cardiac ultrasound. From then on, we gradually identified additional 3 GMC patients with CHD. The original patient with ASD was sent to cardiosurgery department to repair atrial septal first and received arthroscopic surgery later. While the other 3 were cured postoperative of ventricular septal defect (VSD), tetralogy of fallot (TOF), patent ductus arteriosus (PDA), respectively, and had surgery directly. The study gives us 3 proposals: (1) as to CHD children, it is essential to decrease the use of intramuscular injection, (2) paying more attention to cardiac examination especially cardiac ultrasound in perioperative period, and (3) taking 3D-CT to reconstruct gluteal muscles for observing contracture bands clearly in preoperation. However, more larger series of patients are called for to confirm these findings.

  10. Respiratory Muscle Training Improves Diaphragm Citrate Synthase Activity and Hemodynamic Function in Rats with Heart Failure.

    Science.gov (United States)

    Jaenisch, Rodrigo Boemo; Bertagnolli, Mariane; Borghi-Silva, Audrey; Arena, Ross; Lago, Pedro Dal

    2017-01-01

    Enhanced respiratory muscle strength in patients with heart failure positively alters the clinical trajectory of heart failure. In an experimental model, respiratory muscle training in rats with heart failure has been shown to improve cardiopulmonary function through mechanisms yet to be entirely elucidated. The present report aimed to evaluate the respiratory muscle training effects in diaphragm citrate synthase activity and hemodynamic function in rats with heart failure. Wistar rats were divided into four experimental groups: sedentary sham (Sed-Sham, n=8), trained sham (RMT-Sham, n=8), sedentary heart failure (Sed-HF, n=7) and trained heart failure (RMT-HF, n=7). The animals were submitted to a RMT protocol performed 30 minutes a day, 5 days/week, for 6 weeks. In rats with heart failure, respiratory muscle training decreased pulmonary congestion and right ventricular hypertrophy. Deleterious alterations in left ventricular pressures, as well as left ventricular contractility and relaxation, were assuaged by respiratory muscle training in heart failure rats. Citrate synthase activity, which was significantly reduced in heart failure rats, was preserved by respiratory muscle training. Additionally, a negative correlation was found between citrate synthase and left ventricular end diastolic pressure and positive correlation was found between citrate synthase and left ventricular systolic pressure. Respiratory muscle training produces beneficial adaptations in the diaphragmatic musculature, which is linked to improvements in left ventricular hemodynamics and blood pressure in heart failure rats. The RMT-induced improvements in cardiac architecture and the oxidative capacity of the diaphragm may improve the clinical trajectory of patients with heart failure.

  11. Physiological roles of taurine in heart and muscle

    Science.gov (United States)

    2010-01-01

    Taurine (aminoethane sulfonic acid) is an ubiquitous compound, found in very high concentrations in heart and muscle. Although taurine is classified as an amino acid, it does not participate in peptide bond formation. Nonetheless, the amino group of taurine is involved in a number of important conjugation reactions as well as in the scavenging of hypochlorous acid. Because taurine is a fairly inert compound, it is an ideal modulator of basic processes, such as osmotic pressure, cation homeostasis, enzyme activity, receptor regulation, cell development and cell signalling. The present review discusses several physiological functions of taurine. First, the observation that taurine depletion leads to the development of a cardiomyopathy indicates a role for taurine in the maintenance of normal contractile function. Evidence is provided that this function of taurine is mediated by changes in the activity of key Ca2+ transporters and the modulation Ca2+ sensitivity of the myofibrils. Second, in some species, taurine is an established osmoregulator, however, in mammalian heart the osmoregulatory function of taurine has recently been questioned. Third, taurine functions as an indirect regulator of oxidative stress. Although this action of taurine has been widely discussed, its mechanism of action is unclear. A potential mechanism for the antioxidant activity of taurine is discussed. Fourth, taurine stabilizes membranes through direct interactions with phospholipids. However, its inhibition of the enzyme, phospholipid N-methyltransferase, alters the phosphatidylcholine and phosphatidylethanolamine content of membranes, which in turn affects the function of key proteins within the membrane. Finally, taurine serves as a modulator of protein kinases and phosphatases within the cardiomyocyte. The mechanism of this action has not been studied. Taurine is a chemically simple compound, but it has profound effects on cells. This has led to the suggestion that taurine is an

  12. Skeletal muscle beta-receptors and isoproterenol-stimulated vasodilation in canine heart failure

    International Nuclear Information System (INIS)

    Frey, M.J.; Lanoce, V.; Molinoff, P.B.; Wilson, J.R.

    1989-01-01

    To investigate whether heart failure alters beta-adrenergic receptors on skeletal muscle and its associated vasculature, the density of beta-adrenergic receptors, isoproterenol-stimulated adenylate cyclase activity, and coupling of the guanine nucleotide-binding regulatory protein were compared in 18 control dogs and 16 dogs with heart failure induced by 5-8 wk of ventricular pacing at 260 beats/min. Hindlimb vascular responses to isoproterenol were compared in eight controls and eight of the dogs with heart failure. In dogs with heart failure, the density of beta-receptors on skeletal muscle was reduced in both gastrocnemius (control: 50 +/- 5; heart failure: 33 +/- 8 fmol/mg of protein) and semitendinosus muscle (control: 43 +/- 9; heart failure: 27 +/- 9 fmol/mg of protein, both P less than 0.05). Receptor coupling to the ternary complex, as determined by isoproterenol competition curves with and without guanosine 5'-triphosphate (GTP), was unchanged. Isoproterenol-stimulated adenylate cyclase activity was significantly decreased in semitendinosus muscle (control: 52.4 +/- 4.6; heart failure: 36.5 +/- 9.5 pmol.mg-1.min-1; P less than 0.05) and tended to be decreased in gastrocnemius muscle (control: 40.1 +/- 8.5; heart failure: 33.5 +/- 4.5 pmol.mg-1.min-1; P = NS). Isoproterenol-induced hindlimb vasodilation was not significantly different in controls and in dogs with heart failure. These findings suggest that heart failure causes downregulation of skeletal muscle beta-adrenergic receptors, probably due to receptor exposure to elevated catecholamine levels, but does not reduce beta-receptor-mediated vasodilation in muscle

  13. Impaired Skeletal Muscle Vasodilation during Exercise in Heart Failure with Preserved Ejection Fraction

    Science.gov (United States)

    Lee, Joshua F.; Barrett-O’Keefe, Zachary; Nelson, Ashley D.; Garten, Ryan S.; Ryan, John J.; Nativi-Nicolau, Jose N.; Richardson, Russell S.; Wray, D. Walter

    2016-01-01

    Background Exercise intolerance is a hallmark symptom of heart failure patients with preserved ejection fraction (HFpEF), which may be related to an impaired ability to appropriately increase blood flow to the exercising muscle. Methods We evaluated leg blood flow (LBF, ultrasound Doppler), heart rate (HR), stroke volume (SV), cardiac output (CO), and mean arterial blood pressure (MAP, photoplethysmography) during dynamic, single leg knee-extensor (KE) exercise in HFpEF patients (n = 21; 68 ± 2 yrs) and healthy controls (n = 20; 71 ± 2 yrs). Results HFpEF patients exhibited a marked attrition during KE exercise, with only 60% able to complete the exercise protocol. In participants who completed all exercise intensities (0-5-10-15W; HFpEF, n = 13; Controls, n = 16), LBF was not different at 0W and 5W, but was 15-25% lower in HFpEF compared to controls at 10W and 15W (P exercise-induced changes in central variables (HR, SV, CO), as well as MAP, were similar between groups. Conclusions These data reveal a marked reduction in LBF and LVC in HFpEF patients during exercise that cannot be attributed to a disease-related alteration in central hemodynamics, suggesting that impaired vasodilation in the exercising skeletal muscle vasculature may play a key role in the exercise intolerance associated with this patient population. PMID:26970959

  14. Morphology of electrophysiologically identified junctions between Purkinje fibers and ventricular muscle in rabbit and pig hearts

    NARCIS (Netherlands)

    Tranum-Jensen, J.; Wilde, A. A.; Vermeulen, J. T.; Janse, M. J.

    1991-01-01

    Purkinje fiber-ventricular muscle (PV) junctions were identified by extracellular recording in isolated, superfused preparations from rabbit and pig hearts. Microelectrode recordings from different cell types at the PV junctions were obtained, and the cells recorded from were retrieved

  15. Muscle electrical stimulation improves neurovascular control and exercise tolerance in hospitalised advanced heart failure patients.

    Science.gov (United States)

    Groehs, Raphaela V; Antunes-Correa, Ligia M; Nobre, Thais S; Alves, Maria-Janieire Nn; Rondon, Maria Urbana Pb; Barreto, Antônio Carlos Pereira; Negrão, Carlos E

    2016-10-01

    We investigated the effects of muscle functional electrical stimulation on muscle sympathetic nerve activity and muscle blood flow, and, in addition, exercise tolerance in hospitalised patients for stabilisation of heart failure. Thirty patients hospitalised for treatment of decompensated heart failure, class IV New York Heart Association and ejection fraction ≤ 30% were consecutively randomly assigned into two groups: functional electrical stimulation (n = 15; 54 ± 2 years) and control (n = 15; 49 ± 2 years). Muscle sympathetic nerve activity was directly recorded via microneurography and blood flow by venous occlusion plethysmography. Heart rate and blood pressure were evaluated on a beat-to-beat basis (Finometer), exercise tolerance by 6-minute walk test, quadriceps muscle strength by a dynamometer and quality of life by Minnesota questionnaire. Functional electrical stimulation consisted of stimulating the lower limbs at 10 Hz frequency, 150 ms pulse width and 70 mA intensity for 60 minutes/day for 8-10 consecutive days. The control group underwent electrical stimulation at an intensity of electrical stimulation group. Functional electrical stimulation significantly decreased muscle sympathetic nerve activity and increased muscle blood flow and muscle strength. No changes were found in the control group. Walking distance and quality of life increased in both groups. However, these changes were greater in the functional electrical stimulation group. Functional electrical stimulation improves muscle sympathetic nerve activity and vasoconstriction and increases exercise tolerance, muscle strength and quality of life in hospitalised heart failure patients. These findings suggest that functional electrical stimulation may be useful to hospitalised patients with decompensated chronic heart failure. © The European Society of Cardiology 2016.

  16. Cellular fatty acid transport in heart and skeletal muscle as facilitated by proteins

    NARCIS (Netherlands)

    Luiken, J. J.; Schaap, F. G.; van Nieuwenhoven, F. A.; van der Vusse, G. J.; Bonen, A.; Glatz, J. F.

    1999-01-01

    Despite the importance of long-chain fatty acids (FA) as fuels for heart and skeletal muscles, the mechanism of their cellular uptake has not yet been clarified. There is dispute as to whether FA are taken up by the muscle cells via passive diffusion and/or carrier-mediated transport. Kinetic

  17. Skeletal muscle signaling and the heart rate and blood pressure response to exercise

    DEFF Research Database (Denmark)

    Mortensen, Stefan P; Svendsen, Jesper H; Ersbøll, Mads

    2013-01-01

    Endurance training lowers heart rate and blood pressure responses to exercise, but the mechanisms and consequences remain unclear. To determine the role of skeletal muscle for the cardioventilatory response to exercise, 8 healthy young men were studied before and after 5 weeks of 1-legged knee......-extensor training and 2 weeks of deconditioning of the other leg (leg cast). Hemodynamics and muscle interstitial nucleotides were determined during exercise with the (1) deconditioned leg, (2) trained leg, and (3) trained leg with atrial pacing to the heart rate obtained with the deconditioned leg. Heart rate...

  18. Gene expression changes controlling distinct adaptations in the heart and skeletal muscle of a hibernating mammal

    Science.gov (United States)

    Vermillion, Katie L.; Anderson, Kyle J.; Hampton, Marshall

    2015-01-01

    Throughout the hibernation season, the thirteen-lined ground squirrel (Ictidomys tridecemlineatus) experiences extreme fluctuations in heart rate, metabolism, oxygen consumption, and body temperature, along with prolonged fasting and immobility. These conditions necessitate different functional requirements for the heart, which maintains contractile function throughout hibernation, and the skeletal muscle, which remains largely inactive. The adaptations used to maintain these contractile organs under such variable conditions serves as a natural model to study a variety of medically relevant conditions including heart failure and disuse atrophy. To better understand how two different muscle tissues maintain function throughout the extreme fluctuations of hibernation we performed Illumina HiSeq 2000 sequencing of cDNAs to compare the transcriptome of heart and skeletal muscle across the circannual cycle. This analysis resulted in the identification of 1,076 and 1,466 differentially expressed genes in heart and skeletal muscle, respectively. In both heart and skeletal muscle we identified a distinct cold-tolerant mechanism utilizing peroxisomal metabolism to make use of elevated levels of unsaturated depot fats. The skeletal muscle transcriptome also shows an early increase in oxidative capacity necessary for the altered fuel utilization and increased oxygen demand of shivering. Expression of the fetal gene expression profile is used to maintain cardiac tissue, either through increasing myocyte size or proliferation of resident cardiomyocytes, while skeletal muscle function and mass are protected through transcriptional regulation of pathways involved in protein turnover. This study provides insight into how two functionally distinct muscles maintain function under the extreme conditions of mammalian hibernation. PMID:25572546

  19. Heart size and mean muscle fibre cross-sectional area related to birth weight in pigs

    Directory of Open Access Journals (Sweden)

    M. RUUSUNEN

    2008-12-01

    Full Text Available One of the aims in domestic pig breeding has been to increase the size of litters resulting in variation in birth weight of piglets. Pig breeding has also resulted in increased body muscle mass. Muscles with the same size can consist either of large number of thin muscle fibres or small number of thick muscle fibres. Larger body muscle content means that in living animal the heart must pump blood to larger muscle mass than earlier. Our interest in this study was to investigate the relationship between the pig’s birth weight and (i growth performance and carcass composition, (ii the size of organs, and (iii the mean muscle fibre cross-sectional area at slaughter. The study consisted of twenty pigs slaughtered at the age of 165±2 days. The day after the slaughter, the carcass composition was determined by dissecting the chilled carcass into lean, fat, bones, and skin and organs were weighed. The average cross sectional area of muscle fibres was determined from three fast-twitch muscles longissimus dorsi, semimembranosus, gluteus superficialis, and two slow-twitch muscles infraspinatus and masseter. The birth weight of pigs ranged from 0.9 to 2.2 kg. We found no clear relationships between the birth weight and the pig’s growth performance from birth to slaughter. When the birth weight increased the heart weight at slaughter increased as well (P < 0.01. The heart weight was higher in those pigs with high carcass weight (P < 0.05 and with the high weight of total muscle mass in the carcass (P < 0.001. The cross sectional area of muscle fibres in M. longissimus dorsi (P < 0.05, M. semimembranosus (P < 0.10, and M. gluteus superficialis (P < 0.05 was larger in those pigs with low birth weight compared to those found in pigs with high birth weight.;

  20. Mitochondrial specialization revealed by single muscle fiber proteomics

    DEFF Research Database (Denmark)

    Schiaffino, S; Reggiani, C; Kostrominova, T Y

    2015-01-01

    that in skeletal muscle, IDH2 functions in the forward direction of the Krebs cycle and that substrate flux along the cycle occurs predominantly via IDH2 in type 1 fibers and via IDH3 in 2X and 2B fibers. IDH2-mediated conversion of isocitrate to α-ketoglutarate leads to the generation of NADPH, which is critical......We have developed a highly sensitive mass spectrometry-based proteomic workflow to examine the proteome of single muscle fibers. This study revealed significant differences in the mitochondrial proteome of the four major fiber types present in mouse skeletal muscle. Here, we focus on Krebs cycle...... enzymes and in particular on the differential distribution of the two mitochondrial isocitrate dehydrogenases, IDH2 and IDH3. Type 1/slow fibers contain high levels of IDH2 and relatively low levels of IDH3, whereas fast 2X and 2B fibers show an opposite expression pattern. The findings suggest...

  1. Regulation of mechano growth factor in skeletal muscle and heart

    NARCIS (Netherlands)

    Ottens, M.

    2010-01-01

    The mechano growth factor (MGF) is expressed in mechanically overloaded skeletal muscle. MGF was discovered in 1996 as an alternative splice product of the IGF-1 gene. Since then, its significance has been investigated particularly in skeletal muscle, because the local expression of MGF could

  2. Autopsy Findings in Conjoined Twin with Single Heart and Single Liver

    Directory of Open Access Journals (Sweden)

    Kar Asaranti

    2012-01-01

    Full Text Available Thoracoomphalopagus is the commonest type of conjoined twin where the bodies are fused from upper chest to lower chest. The autopsy done can help counsil the parents for further pregnancies and determine the prognosis depending upon the type of cardiac anomaly by Seo classification when detected antenatally. We describe the detail pathological autopsy of such a case with single heart and single liver. A detail autopsy was done on the twin fetus. The twins shared a single heart and sometimes the liver and part of digestive system. The combined weight was 4.1 KG. Both were full-term male babies joined from below the nipple till umbilicus. Autopsy in conjoined twins helps in deciding the type of fusion of the body and also of the heart and great vessels. It can help in counseling parents about future pregnancies that there is no chance of recurrence of this abnormality and no need to be scared.

  3. Measuring mitochondrial respiration in intact single muscle fibers.

    Science.gov (United States)

    Schuh, Rosemary A; Jackson, Kathryn C; Khairallah, Ramzi J; Ward, Christopher W; Spangenburg, Espen E

    2012-03-15

    Measurement of mitochondrial function in skeletal muscle is a vital tool for understanding regulation of cellular bioenergetics. Currently, a number of different experimental approaches are employed to quantify mitochondrial function, with each involving either mechanically or chemically induced disruption of cellular membranes. Here, we describe a novel approach that allows for the quantification of substrate-induced mitochondria-driven oxygen consumption in intact single skeletal muscle fibers isolated from adult mice. Specifically, we isolated intact muscle fibers from the flexor digitorum brevis muscle and placed the fibers in culture conditions overnight. We then quantified oxygen consumption rates using a highly sensitive microplate format. Peak oxygen consumption rates were significantly increased by 3.4-fold and 2.9-fold by simultaneous stimulation with the uncoupling agent, carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (FCCP), and/or pyruvate or palmitate exposure, respectively. However, when calculating the total oxygen consumed over the entire treatment, palmitate exposure resulted in significantly more oxygen consumption compared with pyruvate. Further, as proof of principle for the procedure, we isolated fibers from the mdx mouse model, which has known mitochondrial deficits. We found significant reductions in initial and peak oxygen consumption of 51% and 61% compared with fibers isolated from the wild-type (WT) animals, respectively. In addition, we determined that fibers isolated from mdx mice exhibited less total oxygen consumption in response to the FCCP + pyruvate stimulation compared with the WT mice. This novel approach allows the user to make mitochondria-specific measures in a nondisrupted muscle fiber that has been isolated from a whole muscle.

  4. Multiscale modeling and surgical planning for single ventricle heart patients

    Science.gov (United States)

    Marsden, Alison

    2011-11-01

    Single ventricle heart patients are among the most challenging for pediatric cardiologists to treat, and typically undergo a palliative course of three open-heart surgeries starting immediately after birth. We will present recent tools for modeling blood flow in single ventricle heart patients using a multiscale approach that couples a 3D Navier-Stokes domain to a 0D closed loop lumped parameter network comprised of circuit elements. This coupling allows us to capture the effect of changes in local geometry, such as shunt sizes, on global circulatory dynamics, such as cardiac output. A semi-implicit numerical method is formulated to solve the coupled system in which flow and pressure information is passed between the two domains at the inlets and outlets of the model. A finite element method with outflow stabilization is applied in the 3D Navier-Stokes domain, and the LPN system of ordinary differential equations is solved numerically using a Runge-Kutta method. These tools are coupled via automated scripts to a derivative-free optimization method. Optimization is used to systematically explore surgical designs using clinically relevant cost functions for two stages of single ventricle repair. First, we will present results from optimization of the first stage Blalock Taussig Shunt. Second, we will present results from optimization of a new Y-graft design for the third stage of single ventricle repair called the Fontan surgery. The Y-graft is shown, in simulations, to successfully improve hepatic flow distribution, a known clinical problem. Preliminary clinical experience with the Y-graft will be discussed.

  5. Na+,K+-ATPase concentration in rodent and human heart and skeletal muscle

    DEFF Research Database (Denmark)

    Kjeldsen, K; Bjerregaard, P; Richter, Erik

    1988-01-01

    rats, cardiomyopathic hamsters, and human subjects. These methods have earlier been shown to quantify the Na+,K+-ATPase concentration in muscle tissue with high accuracy. When rats were swim trained for six weeks the heart ventricular muscle Na+,K+-ATPase concentration was increased by 20% (p less than...... was increased by up to 46% (p less than 0.001) and decreased by up to 30% (p less than 0.005) after training and immobilisation respectively. Cardiomyopathic hamsters showed a reduction of 33% (p less than 0.005) in the heart ventricular Na+,K+-ATPase concentration compared with normal hamsters. This decrease...

  6. Arterial wall mechanics as a function of heart rate: role of vascular smooth muscle

    International Nuclear Information System (INIS)

    Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel

    2007-01-01

    Vascular wall viscoelasticity can be evaluated using a first-order lumped model. This model consists of a spring with elastic constant E and a dashpot with viscous constant η. More importantly, this viscoelastic model can be fitted in-vivo measuring arterial pressure and diameter. The aim of this work is to analyze the influence of heart rate over E and η. In two anesthetized sheep, diameter in thoracic aorta and intravascular pressure has been registered. The right atrium was connected to a programmable stimulator through a pair of pace-maker wires to produce changes in stimulation heart rate (HR) from 80 to 160 bpm. Additionally, local activation of vascular smooth muscle was induced with phenylephrine. After converting pressure and diameter signals into stress and strain respectively, E y η were calculated in control state and during muscle activation. The elastic modulus E did not present significant changes with heart rate. The viscous modulus η decreased 49% with a two-fold acceleration in heart rate from 80 to 160 bpm. However, the product η HR remained stable. The viscous modulus η increased 39% with smooth muscle activation. No significant pressure changes were registered during the experiment. The contractile action of vascular smooth muscle could contribute to increasing arterial wall viscosity. The decrease of η when HR increased might be related to smooth muscle relaxation mediated by endothelium activity, which was stimulated by flow increase. We conclude that HR can modulate arterial wall viscoelasticity through endothelium-dependent mechanisms

  7. Production and degradation of AMP in cultured rat skeletal and heart muscle: a comparative study

    International Nuclear Information System (INIS)

    Zoref-Shani, E.; Kessler-Icekson, G.; Shainberg, A.; Sperling, O.

    1986-01-01

    The authors clarify the mechanisms operating in the skeletal and heart muscles to produce and degrade AMP. Rat myotube and cardiomyocyte cultures were prepared and purine synthesis was gauged by the rate of C 14-formate incorporation into purines. It is shown that the cell cultures exhibited capacity for de novo purine synthesis, indicated by incorporation of C 14-formate into purines. The rate of C 14-formate into the cardiomyocyte purines was markedly lower than that in the skeletal muscle myotubes

  8. Discrepancies between Skinned Single Muscle Fibres and Whole Thigh Muscle Function Characteristics in Young and Elderly Human Subjects

    Directory of Open Access Journals (Sweden)

    Hyunseok Jee

    2016-01-01

    Full Text Available We aimed to analyse the mechanical properties of skinned single muscle fibres derived from the vastus lateralis (VL muscle in relation to those of the whole intact thigh muscle and to compare any difference between young and older adults. Sixteen young men (29.25±4.65 years, 11 older men (71.45±2.94 years, 11 young women (29.64±4.88 years, and 7 older women (67.29±1.70 years were recruited. In vivo analyses were performed for mechanical properties such as isokinetic performance, isometric torque, and power. Specific force and maximum shortening velocity (Vo were measured with single muscle fibres. Sex difference showed greater impact on the functional properties of both the whole muscle (p<0.01 and single muscle fibres than aging (p<0.05. Sex difference, rather than aging, yielded more remarkable differences in gross mechanical properties in the single muscle fibre study in which significant differences between young men and young women were found only in the cross-sectional area and Vo (p<0.05. Age and sex differences reflect the mechanical properties of both single muscle fibres and whole thigh muscle, with the whole muscle yielding more prominent functional properties.

  9. Transient impairments in single muscle fibre contractile function after prolonged cycling in elite endurance athletes

    DEFF Research Database (Denmark)

    Hvid, L G; Gejl, Kasper Degn; Bech, R D

    2013-01-01

    Prolonged muscle activity impairs whole-muscle performance and function. However, little is known about the effects of prolonged muscle activity on the contractile function of human single muscle fibres. The purpose of this study was to investigate the effects of prolonged exercise and subsequent...

  10. Single muscle fiber proteomics reveals unexpected mitochondrial specialization

    DEFF Research Database (Denmark)

    Murgia, Marta; Nagaraj, Nagarjuna; Deshmukh, Atul S

    2015-01-01

    Mammalian skeletal muscles are composed of multinucleated cells termed slow or fast fibers according to their contractile and metabolic properties. Here, we developed a high-sensitivity workflow to characterize the proteome of single fibers. Analysis of segments of the same fiber by traditional...... and unbiased proteomics methods yielded the same subtype assignment. We discovered novel subtype-specific features, most prominently mitochondrial specialization of fiber types in substrate utilization. The fiber type-resolved proteomes can be applied to a variety of physiological and pathological conditions...

  11. Human cytochrome c oxidase isoenzymes from heart and skeletal muscle; purification and properties

    NARCIS (Netherlands)

    Sinjorgo, K. M.; Hakvoort, T. B.; Durak, I.; Draijer, J. W.; Post, J. K.; Muijsers, A. O.

    1987-01-01

    Human cytochrome c oxidase was isolated in an active form from heart and from skeletal muscle by a fast, small-scale isolation method. The procedure involves differential solubilisation of the oxidase from mitochondrial fragments by laurylmaltoside and KCl, followed by size-exclusion

  12. Fatty acid composition of muscle and heart tissue of Nile perch ...

    African Journals Online (AJOL)

    The fatty acid composition in the heart tissue and muscle tissue of the Nile perch, Lates niloticus, and Nile tilapia, Oreochromis niloticus populations from Lakes Kioga and Victoria was determined by methanolysis and gas chromatography of the resulting fatty acid methyl esters. The analytical data were treated by ...

  13. Single muscle fiber gene expression with run taper.

    Directory of Open Access Journals (Sweden)

    Kevin Murach

    Full Text Available This study evaluated gene expression changes in gastrocnemius slow-twitch myosin heavy chain I (MHC I and fast-twitch (MHC IIa muscle fibers of collegiate cross-country runners (n = 6, 20±1 y, VO₂max = 70±1 ml•kg-1•min-1 during two distinct training phases. In a controlled environment, runners performed identical 8 kilometer runs (30:18±0:30 min:s, 89±1% HRmax while in heavy training (∼72 km/wk and following a 3 wk taper. Training volume during the taper leading into peak competition was reduced ∼50% which resulted in improved race times and greater cross-section and improved function of MHC IIa fibers. Single muscle fibers were isolated from pre and 4 hour post run biopsies in heavily trained and tapered states to examine the dynamic acute exercise response of the growth-related genes Fibroblast growth factor-inducible 14 (FN14, Myostatin (MSTN, Heat shock protein 72 (HSP72, Muscle ring-finger protein-1 (MURF1, Myogenic factor 6 (MRF4, and Insulin-like growth factor 1 (IGF1 via qPCR. FN14 increased 4.3-fold in MHC IIa fibers with exercise in the tapered state (P<0.05. MSTN was suppressed with exercise in both fiber types and training states (P<0.05 while MURF1 and HSP72 responded to running in MHC IIa and I fibers, respectively, regardless of training state (P<0.05. Robust induction of FN14 (previously shown to strongly correlate with hypertrophy and greater overall transcriptional flexibility with exercise in the tapered state provides an initial molecular basis for fast-twitch muscle fiber performance gains previously observed after taper in competitive endurance athletes.

  14. Sarcopenia, cachexia, and muscle performance in heart failure: Review update 2016.

    Science.gov (United States)

    Saitoh, Masakazu; Ishida, Junichi; Doehner, Wolfram; von Haehling, Stephan; Anker, Markus S; Coats, Andrew J S; Anker, Stefan D; Springer, Jochen

    2017-07-01

    Cachexia in the context of heart failure (HF) has been termed cardiac cachexia, and represents a progressive involuntary weight loss. Cachexia is mainly the result of an imbalance in the homeostasis of muscle protein synthesis and degradation due to a lower activity of protein synthesis pathways and an over-activation of protein degradation. In addition, muscle wasting leads to of impaired functional capacity, even after adjusting for clinical relevant variables in patients with HF. However, there is no sufficient therapeutic strategy in muscle wasting in HF patients and very few studies in animal models. Exercise training represents a promising intervention that can prevent or even reverse the process of muscle wasting, and worsening the muscle function and performance in HF with muscle wasting and cachexia. The pathological mechanisms and effective therapeutic approach of cardiac cachexia remain uncertain, because of the difficulty to establish animal cardiac cachexia models, thus novel animal models are warranted. Furthermore, the use of improved animal models will lead to a better understanding of the pathways that modulate muscle wasting and therapeutics of muscle wasting of cardiac cachexia. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Oxidative stress impairs insulin signal in skeletal muscle and causes insulin resistance in postinfarct heart failure.

    Science.gov (United States)

    Ohta, Yukihiro; Kinugawa, Shintaro; Matsushima, Shouji; Ono, Taisuke; Sobirin, Mochamad A; Inoue, Naoki; Yokota, Takashi; Hirabayashi, Kagami; Tsutsui, Hiroyuki

    2011-05-01

    Insulin resistance has been shown to occur as a consequence of heart failure. However, its exact mechanisms in this setting remain unknown. We have previously reported that oxidative stress is enhanced in the skeletal muscle from mice with heart failure after myocardial infarction (MI) (30). This study is aimed to investigate whether insulin resistance in postinfarct heart failure is due to the impairment of insulin signaling in the skeletal muscle caused by oxidative stress. Mice were divided into four groups: sham operated (sham); sham treated with apocynin, an inhibitor of NAD(P)H oxidase activation (10 mmol/l in drinking water); MI; and MI treated with apocynin. After 4 wk, intraperitoneal insulin tolerance tests were performed, and skeletal muscle samples were obtained for insulin signaling measurements. MI mice showed left ventricular dilation and dysfunction by echocardiography and increased left ventricular end-diastolic pressure and lung weight. The decrease in glucose level after insulin load significantly attenuated in MI compared with sham. Insulin-stimulated serine phosphorylation of Akt and glucose transporter-4 translocation were decreased in MI mice by 61 and 23%, respectively. Apocynin ameliorated the increase in oxidative stress and NAD(P)H oxidase activities measured by the lucigenin assay in the skeletal muscle after MI. It also improved insulin resistance and inhibited the decrease of Akt phosphorylation and glucose transporter-4 translocation. Insulin resistance was induced by the direct impairment of insulin signaling in the skeletal muscle from postinfarct heart failure, which was associated with the enhanced oxidative stress via NAD(P)H oxidase.

  16. Calcium versus strontium handling by the heart muscle.

    Science.gov (United States)

    Hendrych, Michal; Olejnickova, Veronika; Novakova, Marie

    2016-01-01

    Calcium plays a crucial role in numerous processes in living systems, from both intracellular and intercellular signalling to blood clotting. Calcium can be replaced by strontium in various intracellular processes due to high level of their similarity and strontium thus may serve as a valuable tool for different experimental studies. On the other hand, strontium is also used in clinical medicine and is commonly taken to the human body with food and water. The negative cardiac side effects of strontium therapy of osteoporosis and bone metastases are well known, but still not fully explained. This fact explains enhanced interest in this element and its impact on human body. This article reviews effects of calcium and strontium on several biochemical and physiological processes, with special emphasis on cardiac muscle.

  17. Direct and indirect assessment of skeletal muscle blood flow in chronic congestive heart failure

    International Nuclear Information System (INIS)

    LeJemtel, T.H.; Scortichini, D.; Katz, S.

    1988-01-01

    In patients with chronic congestive heart failure (CHF), skeletal muscle blood flow can be measured directly by the continuous thermodilution technique and by the xenon-133 clearance method. The continuous thermodilution technique requires retrograde catheterization of the femoral vein and, thus, cannot be repeated conveniently in patients during evaluation of pharmacologic interventions. The xenon-133 clearance, which requires only an intramuscular injection, allows repeated determination of skeletal muscle blood flow. In patients with severe CHF, a fixed capacity of the skeletal muscle vasculature to dilate appears to limit maximal exercise performance. Moreover, the changes in peak skeletal muscle blood flow noted during long-term administration of captopril, an angiotensin-converting enzyme inhibitor, appears to correlate with the changes in aerobic capacity. In patients with CHF, resting supine deep femoral vein oxygen content can be used as an indirect measurement of resting skeletal muscle blood flow. The absence of a steady state complicates the determination of peak skeletal muscle blood flow reached during graded bicycle or treadmill exercise in patients with chronic CHF. Indirect assessments of skeletal muscle blood flow and metabolism during exercise performed at submaximal work loads are currently developed in patients with chronic CHF

  18. Inspiratory Muscle Training Improves Intercostal and Forearm Muscle Oxygenation in Patients With Chronic Heart Failure: Evidence of the Origin of the Respiratory Metaboreflex.

    Science.gov (United States)

    Moreno, Adalgiza M; Toledo-Arruda, Alessandra C; Lima, Jéssica S; Duarte, Carolina S; Villacorta, Humberto; Nóbrega, Antonio C L

    2017-09-01

    The impact of inspiratory muscle training (IMT) on respiratory and peripheral muscle oxygenation and perfusion during inspiratory muscle fatigue in patients with chronic heart failure (HF) has not been established. Twenty-six patients with chronic HF were randomly assigned to either 8 weeks of IMT or a control group. Inspiratory fatigue was induced by means of a progressive inspiratory resistive loading protocol until there was an inability to sustain inspiratory pressure, when the inspiratory muscle metaboreflex should be activated. The main outcomes were intercostal and forearm muscle oxygen saturation and deoxygenation as measured by means of near-infrared spectroscopy (NIRS) and blood lactate levels. Inspiratory muscle strength was increased by 78% (P muscles and the increase in blood lactate during respiratory fatigue (P muscle oxygen demand-delivery mismatch during respiratory fatigue in patients with chronic HF. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Grafting of a single donor myofibre promotes hypertrophy in dystrophic mouse muscle.

    Directory of Open Access Journals (Sweden)

    Luisa Boldrin

    Full Text Available Skeletal muscle has a remarkable capability of regeneration following injury. Satellite cells, the principal muscle stem cells, are responsible for this process. However, this regenerative capacity is reduced in muscular dystrophies or in old age: in both these situations, there is a net loss of muscle fibres. Promoting skeletal muscle muscle hypertrophy could therefore have potential applications for treating muscular dystrophies or sarcopenia. Here, we observed that muscles of dystrophic mdx nude host mice that had been acutely injured by myotoxin and grafted with a single myofibre derived from a normal donor mouse exhibited increased muscle area. Transplantation experiments revealed that the hypertrophic effect is mediated by the grafted fibre and does not require either an imposed injury to the host muscle, or the contribution of donor cells to the host muscle. These results suggest the presence of a crucial cross-talk between the donor fibre and the host muscle environment.

  20. Grafting of a Single Donor Myofibre Promotes Hypertrophy in Dystrophic Mouse Muscle

    Science.gov (United States)

    Boldrin, Luisa; Morgan, Jennifer E.

    2013-01-01

    Skeletal muscle has a remarkable capability of regeneration following injury. Satellite cells, the principal muscle stem cells, are responsible for this process. However, this regenerative capacity is reduced in muscular dystrophies or in old age: in both these situations, there is a net loss of muscle fibres. Promoting skeletal muscle muscle hypertrophy could therefore have potential applications for treating muscular dystrophies or sarcopenia. Here, we observed that muscles of dystrophic mdx nude host mice that had been acutely injured by myotoxin and grafted with a single myofibre derived from a normal donor mouse exhibited increased muscle area. Transplantation experiments revealed that the hypertrophic effect is mediated by the grafted fibre and does not require either an imposed injury to the host muscle, or the contribution of donor cells to the host muscle. These results suggest the presence of a crucial cross-talk between the donor fibre and the host muscle environment. PMID:23349935

  1. Metabolic adaptations of skeletal muscle to voluntary wheel running exercise in hypertensive heart failure rats

    DEFF Research Database (Denmark)

    Schultz, R L; Kullman, E L; Waters, Ryan

    2013-01-01

    SHHF and Wistar-Furth (WF) rats were randomized to sedentary (SHHFsed and WFsed) and exercise groups (SHHFex and WFex). The exercise groups had access to running wheels from 6-22 months of age. Hindlimb muscles were obtained for metabolic measures that included mitochondrial enzyme function......The Spontaneously Hypertensive Heart Failure (SHHF) rat mimics the human progression of hypertension from hypertrophy to heart failure. However, it is unknown whether SHHF animals can exercise at sufficient levels to observe beneficial biochemical adaptations in skeletal muscle. Thirty-seven female...... and expression, and glycogen utilization. The SHHFex rats ran a greater distance and duration as compared to the WFex rats (Pmuscle citrate synthase and beta-hydroxyacyl-CoA dehydrogenase enzyme activity was not altered in the SHHFex group...

  2. Is the soleus a sentinel muscle for impaired aerobic capacity in heart failure?

    Science.gov (United States)

    Panizzolo, Fausto A; Maiorana, Andrew J; Naylor, Louise H; Lichtwark, Glen A; Dembo, Lawrence; Lloyd, David G; Green, Daniel J; Rubenson, Jonas

    2015-03-01

    Skeletal muscle wasting is well documented in chronic heart failure (CHF). This article provides a more detailed understanding of the morphology behind this muscle wasting and the relation between muscle morphology, strength, and exercise capacity in CHF. We investigated the effect of CHF on lower limb lean mass, detailed muscle-tendon architecture of the individual triceps surae muscles (soleus (SOL), medial gastrocnemius, and lateral gastrocnemius) and how these parameters relate to exercise capacity and strength. Eleven patients with CHF and 15 age-matched controls were recruited. Lower limb lean mass was assessed by dual energy x-ray absorptiometry and the architecture of skeletal muscle and tendon properties by ultrasound. Plantarflexor strength was assessed by dynamometry. Patients with CHF exhibited approximately 25% lower combined triceps surae volume and physiological cross-sectional area (PCSA) compared with those of control subjects (P < 0.05), driven in large part by reductions in the SOL. Only the SOL volume and the SOL and medial gastrocnemius physiological cross-sectional area were statistically different between groups after normalizing to lean body mass and body surface area, respectively. Total lower limb lean mass did not differ between CHF and control subjects, further highlighting the SOL specificity of muscle wasting in CHF. Moreover, the volume of the SOL and plantarflexor strength correlated strongly with peak oxygen uptake (V˙O2peak) in patients with CHF. These findings suggest that the SOL may be a sentinel skeletal muscle in CHF and provide a rationale for including plantarflexor muscle training in CHF care.

  3. Heart rate variability and muscle sympathetic nerve activity response to acute stress: the effect of breathing

    OpenAIRE

    DeBeck, Lindsay D.; Petersen, Stewart R.; Jones, Kelvin E.; Stickland, Michael K.

    2010-01-01

    Previous research has suggested a relationship between low-frequency power of heart rate variability (HRV; LF in normalized units, LFnu) and muscle sympathetic nerve activity (MSNA). However, investigations have not systematically controlled for breathing, which can modulate both HRV and MSNA. Accordingly, the aims of this experiment were to investigate the possibility of parallel responses in MSNA and HRV (LFnu) to selected acute stressors and the effect of controlled breathing. After data w...

  4. [Evaluation of heart impact in the 100 m extreme intensity sport using near-infrared non-invasive muscle oxygen detecting device and sports heart rate detection technology].

    Science.gov (United States)

    Wang, Pei-Yong; Long, Fei-Xiao; Fu, Lan-Ying; Li, Yue; Ding, Hai-Shu; Qu, An-Lian; Zhou, Xiao-Ping

    2010-02-01

    Using continuous two wavelength near-infrared technology to detect the variation in the consistency of oxygen hemoglobin in the muscle and the sports heart rate wireless real time collection technology, we devised the real time muscle tissue oxygenation and instantaneous heart rate experiment scheme and implemented it for the process of the 100 m run with two parameters given simultaneously. The experiment shows that the concentration of the oxygen hemoglobin in the muscle tissue continues decreasing after the end of the 100 m run, and the time interval between the moment when the concentration of the oxygen hemoglobin attains the minimum value and the moment when the athletes finish the 100 m run is (6.65 +/- 1.10) sec; while the heart rate continues increasing after the end of the 100 m run, and the time interval between the moment when the heart rate attains the maximum value and the moment when the athletes finish the 100 m run is (8.00 +/- 1.57) sec. The results show that the two wavelength near-infrared tissue oxygenation detection technology and the sports heart rate real time collection equipment can accurately measure the sports tissue oxygenation and the heart rate in the extreme intensity sport, and reveal the process of muscle oxygen transportation and consumption and its dynamic character with the heart rate in the extreme intensity sport.

  5. Cytophotometric analysis of reaction rates of succinate and lactate dehydrogenase activity in rat liver, heart muscle and tracheal epithelium

    NARCIS (Netherlands)

    van Noorden, C. J.; Vogels, I. M.

    1989-01-01

    Reaction rates of succinate and lactate dehydrogenase activity in cryostat sections of rat liver, tracheal epithelium and heart muscle were monitored by continuous measurement of formazan formation by cytophotometry at room temperature. Incubation media contained polyvinyl alcohol as tissue

  6. Electrophysiological changes of Papillary Muscles in Guinea Pigs with iron deficiency anemia and heart failure

    Directory of Open Access Journals (Sweden)

    Ling Fan1

    2017-04-01

    Full Text Available Objective: To investigate the changes of left ventricular papillary muscle action potentials in guinea pigs with iron deficiency anemia and heart failure. Methods: A total of 20 cases of iron deficiency anemia with heart failure were treated with experimental group and 10 normal guinea pigs as control group. Blood samples were collected to determine hemoglobin content, red blood cell number and whole blood iron index, and the changes of cardiac function and hemodynamics were detected by 6 240 biological signal collection system to determine whether the model was successful or not, Intracellular microelectrode technique was used to determine the action potentials of the papillary muscles in the model group and the control group. the potential amplitudes (APA, overshoot values (APA, maximum depolarization rate (Vmax, 20 % of repolarization, 50 % and 90 % of repolarization (APD20, APD50 and APD90 and the average velocity of repolarization were measured. Compare statistical difference between the model group and the control group. Results: 14 cases of model group survived completely, compared with control group, APD50 and APD90 prolonged, and the average velocity decreased. Conclusions: the action potential repolarization duration in the guinea pig papillary muscle of iron deficiency anemia with heart failure is prolonged, and the average repolarization velocity is slow.

  7. Metabolism of 15(p123I iodophenyl-)pentadecanoic acid in heart muscle and noncardiac tissues

    International Nuclear Information System (INIS)

    Reske, S.N.; Sauer, W.; Winkler, C.; Machulla, H.J.; Knust, J.

    1985-01-01

    The uptake and turnover of W(p 123 I iodophenyl-)pentadecanoic acid (I-PPA), a radioiodinated free-fatty-acid analog, was examined in the heart, lung, liver, kidneys, spleen, and skeletal muscle of rats. At 2 min post injection, a high cardiac uptake of 4.4% dose per gram had already been achieved; this was followed by a rapid, two-component, tracer clearance. The kinetics of tissue concentrations of labeled hydrophilic catabolites indicated a rapid oxidation of I-PPA and the subsequent washout of I-PPA catabolites from heart-muscle tissue. The fractional distribution of the labeled cardiac lipids compared favorably with previously reported values for 3 H-oleic- or 14 C-palmitic-acid-labeled myocardial lipids. Typical patterns of I-PPA metabolism were observed in tissues; dedpending on primary fatty-acid oxidation, lipid metabolism regulation, or I-PPA-catabolite excretion. The tissue concentrations and kinetics of I-PPA and its metabolites in the heart muscle indicated that general pathways of cardiac-lipid metabolism are traced by this new γ-emitting isotope-labeled radiopharmaceutical. (orig.)

  8. Assessment of skeletal muscle fatigue of road maintenance workers based on heart rate monitoring and myotonometry

    Directory of Open Access Journals (Sweden)

    Kalkis Henrijs

    2006-07-01

    Full Text Available Abstract Objective This research work is dedicated to occupational health problems caused by ergonomic risks. The research object was road building industry, where workers have to work very intensively, have long work hours, are working in forced/constrained work postures and overstrain during the work specific parts of their bodies. The aim of this study was to evaluate the work heaviness degree and to estimate the muscle fatigue of workers after one week work cycle. The study group consisted of 10 road construction and maintenance workers and 10 pavers aged between 20 and 60 years. Methods Physical load were analyzed by measuring heart rate (HR, work postures (OWAS and perceived exertion (RPE. Assessments of the muscles strain and functional state (tone were carried out using myotonometric (MYO measurements. The reliability of the statistical processing of heart rate monitoring and myotonometry data was determined using correlating analysis. Results This study showed that that road construction and repairing works should be considered as a hard work according to average metabolic energy consumption 8.1 ± 1.5 kcal/min; paving, in its turn, was a moderately hard work according to 7.2 ± 1.1 kcal/min. Several muscle tone levels were identified allowing subdivision of workers into three conditional categories basing on muscle tone and fatigue: I – absolute muscle relaxation and ability to relax; II – a state of equilibrium, when muscles are able to adapt to the work load and are partly able to relax; and III – muscle fatigue and increased tone. It was also found out that the increase of muscle tone and fatigue mainly depend on workers physical preparedness and length of service, and less – on their age. Conclusion We have concluded that a complex ergonomic analysis consisting of heart rate monitoring, assessment of compulsive working postures and myotonometry is appropriate to assess the work heaviness degree and can provide prognosis of

  9. Muscle strength in youth and cardiovascular risk in young adulthood (the European Youth Heart Study)

    DEFF Research Database (Denmark)

    Grøntved, Anders; Ried-Larsen, Mathias; Møller, Niels Christian

    2015-01-01

    BACKGROUND: Whether muscle strength in youth is related to cardiovascular risk later in life independent of cardiorespiratory fitness is unclear. METHODS: We examined the independent association of isometric muscle strength in youth with cardiovascular risk factors in young adulthood using data...... from the Danish European Youth Heart Study; a population-based prospective cohort study among boys and girls (n=332) followed for up to 12 years. In youth maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain-gauge dynamometer...... and cardiorespiratory fitness was obtained from a maximal cycle ergometer test. Cardiovascular risk factors were obtained in youth and in young adulthood. Associations were examined using multivariable-adjusted regression models including major confounding factors. RESULTS: Each 1 SD difference in isometric muscle...

  10. Is there any benefit using low-intensity inspiratory and peripheral muscle training in heart failure? A randomized clinical trial.

    Science.gov (United States)

    Kawauchi, Tatiana Satie; Umeda, Iracema Ioco Kikuchi; Braga, Lays Magalhães; Mansur, Antonio de Pádua; Rossi-Neto, João Manoel; Guerra de Moraes Rego Sousa, Amanda; Hirata, Mário Hiroyuki; Cahalin, Lawrence P; Nakagawa, Naomi Kondo

    2017-09-01

    Inspiratory and peripheral muscle training improves muscle strength, exercise tolerance, and quality of life in patients with chronic heart failure (HF). However, studies investigating different workloads for these exercise modalities are still lacking. To examine the effects of low and moderate intensities on muscle strength, functional capacity, and quality of life. A randomized controlled trial. Thirty-five patients with stable HF (aged >18 years, NYHA II/III, LVEF training group (LIPRT, n = 13, 15% maximal inspiratory workload, and 0.5 kg of peripheral muscle workload) or moderate-intensity training group (MIPRT, n = 13, 30% maximal inspiratory workload and 50% of one maximum repetition of peripheral muscle workload). The outcomes were: respiratory and peripheral muscle strength, pulmonary function, exercise tolerance by the 6-minute walk test, symptoms based on the NYHA functional class, and quality of life using the Minnesota Living with Heart Failure Questionnaire. All groups showed similar quality-of-life improvements. Low and moderate intensities training programs improved inspiratory muscle strength, peripheral muscle strength, and walking distance. However, only moderate intensity improved expiratory muscle strength and NYHA functional class in HF patients. The low-intensity inspiratory and peripheral resistance muscle training improved inspiratory and peripheral muscle strength and walking distance, demonstrating that LIPRT is an efficient rehabilitation method for debilitated HF patients. In addition, the moderate-intensity resistance training also improved expiratory muscle strength and NYHA functional class in HF patients.

  11. The Popeye domain containing 2 (popdc2) gene in zebrafish is required for heart and skeletal muscle development

    Science.gov (United States)

    Kirchmaier, Bettina C.; Poon, Kar Lai; Schwerte, Thorsten; Huisken, Jan; Winkler, Christoph; Jungblut, Benno; Stainier, Didier Y.; Brand, Thomas

    2013-01-01

    The Popeye domain containing (Popdc) genes encode a family of transmembrane proteins with an evolutionary conserved Popeye domain. These genes are abundantly expressed in striated muscle tissue, however their function is not well understood. In this study we have investigated the role of the popdc2 gene in zebrafish. Popdc2 transcripts were detected in the embryonic myocardium and transiently in the craniofacial and tail musculature. Morpholino oligonucleotide-mediated knockdown of popdc2 resulted in aberrant development of skeletal muscle and heart. Muscle segments in the trunk were irregularly shaped and craniofacial muscles were severely reduced or even missing. In the heart, pericardial edema was prevalent in the morphants and heart chambers were elongated and looping was abnormal. These pathologies in muscle and heart were alleviated after reducing the morpholino concentration. However the heart still was abnormal displaying cardiac arrhythmia at later stages of development. Optical recordings of cardiac contractility revealed irregular ventricular contractions with a 2:1, or 3:1 atrial/ventricular conduction ratio, which caused a significant reduction in heart frequency. Recordings of calcium transients with high spatiotemporal resolution using a transgenic calcium indicator line (Tg(cmlc2:gCaMP)s878) and SPIM microscopy confirmed the presence of a severe arrhythmia phenotype. Our results identify popdc2 as a gene important for striated muscle differentiation and cardiac morphogenesis. In addition it is required for the development of the cardiac conduction system. PMID:22290329

  12. Hemodynamic responses to small muscle mass exercise in heart failure patients with reduced ejection fraction

    Science.gov (United States)

    Barrett-O'Keefe, Zachary; Lee, Joshua F.; Berbert, Amanda; Witman, Melissa A. H.; Nativi-Nicolau, Jose; Stehlik, Josef; Richardson, Russell S.

    2014-01-01

    To better understand the mechanisms responsible for exercise intolerance in heart failure with reduced ejection fraction (HFrEF), the present study sought to evaluate the hemodynamic responses to small muscle mass exercise in this cohort. In 25 HFrEF patients (64 ± 2 yr) and 17 healthy, age-matched control subjects (64 ± 2 yr), mean arterial pressure (MAP), cardiac output (CO), and limb blood flow were examined during graded static-intermittent handgrip (HG) and dynamic single-leg knee-extensor (KE) exercise. During HG exercise, MAP increased similarly between groups. CO increased significantly (+1.3 ± 0.3 l/min) in the control group, but it remained unchanged across workloads in HFrEF patients. At 15% maximum voluntary contraction (MVC), forearm blood flow was similar between groups, while HFrEF patients exhibited an attenuated increase at the two highest intensities compared with controls, with the greatest difference at the highest workload (352 ± 22 vs. 492 ± 48 ml/min, HFrEF vs. control, 45% MVC). During KE exercise, MAP and CO increased similarly across work rates between groups. However, HFrEF patients exhibited a diminished leg hyperemic response across all work rates, with the most substantial decrement at the highest intensity (1,842 ± 64 vs. 2,675 ± 81 ml/min; HFrEF vs. control, 15 W). Together, these findings indicate a marked attenuation in exercising limb perfusion attributable to impairments in peripheral vasodilatory capacity during both arm and leg exercise in patients with HFrEF, which likely plays a role in limiting exercise capacity in this patient population. PMID:25260608

  13. From single muscle fiber to whole muscle mechanics: a finite element model of a muscle bundle with fast and slow fibers.

    Science.gov (United States)

    Marcucci, Lorenzo; Reggiani, Carlo; Natali, Arturo N; Pavan, Piero G

    2017-12-01

    Muscles exhibit highly complex, multi-scale architecture with thousands of muscle fibers, each with different properties, interacting with each other and surrounding connective structures. Consequently, the results of single-fiber experiments are scarcely linked to the macroscopic or whole muscle behavior. This is especially true for human muscles where it would be important to understand of how skeletal muscles disorders affect patients' life. In this work, we developed a mathematical model to study how fast and slow muscle fibers, well characterized in single-fiber experiments, work and generate together force and displacement in muscle bundles. We characterized the parameters of a Hill-type model, using experimental data on fast and slow single human muscle fibers, and comparing experimental data with numerical simulations obtained from finite element (FE) models of single fibers. Then, we developed a FE model of a bundle of 19 fibers, based on an immunohistochemically stained cross section of human diaphragm and including the corresponding properties of each slow or fast fiber. Simulations of isotonic contractions of the bundle model allowed the generation of its apparent force-velocity relationship. Although close to the average of the force-velocity curves of fast and slow fibers, the bundle curve deviates substantially toward the fast fibers at low loads. We believe that the present model and the characterization of the force-velocity curve of a fiber bundle represents the starting point to link the single-fiber properties to those of whole muscle with FE application in phenomenological models of human muscles.

  14. Long-Term Blocking of Calcium Channels in mdx Mice Results in Differential Effects on Heart and Skeletal Muscle

    DEFF Research Database (Denmark)

    Jørgensen, Louise Helskov; Blain, Alison; Greally, Elizabeth

    2011-01-01

    in older mice. However, streptomycin treatment did not show positive effects in diaphragm or heart muscle, and heart pathology was worsened. Thus, blocking calcium channels even before disease onset does not prevent dystrophy, making this an unlikely treatment for DMD. These findings highlight...

  15. Analysis of Skeletal Muscle Torque Capacity and Circulating Ceramides in Patients with Advanced Heart Failure.

    Science.gov (United States)

    Brunjes, Danielle L; Dunlop, Mark; Wu, Christina; Jones, Meaghan; Kato, Tomoko S; Kennel, Peter J; Armstrong, Hilary F; Choo, Tse-Hwei; Bartels, Matthew N; Forman, Daniel E; Mancini, Donna M; Schulze, P Christian

    2016-05-01

    Heart failure (HF)-related exercise intolerance is thought to be perpetuated by peripheral skeletal muscle functional, structural, and metabolic abnormalities. We analyzed specific dynamics of muscle contraction in patients with HF compared with healthy, sedentary controls. Isometric and isokinetic muscle parameters were measured in the dominant upper and lower limbs of 45 HF patients and 15 healthy age-matched controls. Measurements included peak torque normalized to body weight, work normalized to body weight, power, time to peak torque, and acceleration and deceleration to maximum strength times. Body morphometry (dual energy X-ray absorptiometry scan) and circulating fatty acids and ceramides (lipodomics) were analyzed in a subset of subjects (18 HF and 9 controls). Extension and flexion time-to-peak torque was longer in the lower limbs of HF patients. Furthermore, acceleration and deceleration times in the lower limbs were also prolonged in HF subjects. HF subjects had increased adiposity and decreased lean muscle mass compared with controls. Decreased circulating unsaturated fatty acids and increased ceramides were found in subjects with HF. Delayed torque development suggests skeletal muscle impairments that may reflect abnormal neuromuscular functional coupling. These impairments may be further compounded by increased adiposity and inflammation associated with increased ceramides. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Discrepancies between Skinned Single Muscle Fibres and Whole Thigh Muscle Function Characteristics in Young and Elderly Human Subjects

    OpenAIRE

    Hyunseok Jee; Jae-Young Lim

    2016-01-01

    We aimed to analyse the mechanical properties of skinned single muscle fibres derived from the vastus lateralis (VL) muscle in relation to those of the whole intact thigh muscle and to compare any difference between young and older adults. Sixteen young men (29.25 ? 4.65 years), 11 older men (71.45 ? 2.94 years), 11 young women (29.64 ? 4.88 years), and 7 older women (67.29 ? 1.70 years) were recruited. In vivo analyses were performed for mechanical properties such as isokinetic performance, ...

  17. Acute electromyostimulation decreases muscle sympathetic nerve activity in patients with advanced chronic heart failure (EMSICA Study.

    Directory of Open Access Journals (Sweden)

    Marc Labrunée

    Full Text Available Muscle passive contraction of lower limb by neuromuscular electrostimulation (NMES is frequently used in chronic heart failure (CHF patients but no data are available concerning its action on sympathetic activity. However, Transcutaneous Electrical Nerve Stimulation (TENS is able to improve baroreflex in CHF. The primary aim of the present study was to investigate the acute effect of TENS and NMES compared to Sham stimulation on sympathetic overactivity as assessed by Muscle Sympathetic Nerve Activity (MSNA.We performed a serie of two parallel, randomized, double blinded and sham controlled protocols in twenty-two CHF patients in New York Heart Association (NYHA Class III. Half of them performed stimulation by TENS, and the others tested NMES.Compare to Sham stimulation, both TENS and NMES are able to reduce MSNA (63.5 ± 3.5 vs 69.7 ± 3.1 bursts / min, p < 0.01 after TENS and 51.6 ± 3.3 vs 56.7 ± 3.3 bursts / min, p < 0, 01 after NMES. No variation of blood pressure, heart rate or respiratory parameters was observed after stimulation.The results suggest that sensory stimulation of lower limbs by electrical device, either TENS or NMES, could inhibit sympathetic outflow directed to legs in CHF patients. These properties could benefits CHF patients and pave the way for a new non-pharmacological approach of CHF.

  18. Myofascial force transmisison between antagonistic rat lower limb muscles: effects of single muscle or muscle group lengthening

    NARCIS (Netherlands)

    Meijer, Hanneke J.M; Rijkelijkhuizen, Josina M.; Huijing, P.A.J.B.M.

    2007-01-01

    Effects of lengthening of the whole group of anterior crural muscles (tibialis anterior and extensor hallucis longus muscles (TA + EHL) and extensor digitorum longus (EDL)) on myofascial interaction between synergistic EDL and TA + EHL muscles, and on myofascial force transmission between anterior

  19. Myofascial force transmission between antagonistic rat lower limb muscles: Effects of single muscle or muscle group lengthening.

    NARCIS (Netherlands)

    Meijer, H.J.M.; Rijkelijkhuizen, J.M.; Huijing, P.A.J.B.M.

    2007-01-01

    Effects of lengthening of the whole group of anterior crural muscles (tibialis anterior and extensor hallucis longus muscles (TA + EHL) and extensor digitorum longus (EDL)) on myofascial interaction between synergistic EDL and TA + EHL muscles, and on myofascial force transmission between anterior

  20. Effect of single bout versus repeated bouts of stretching on muscle recovery following eccentric exercise.

    Science.gov (United States)

    Torres, Rui; Pinho, Francisco; Duarte, José Alberto; Cabri, Jan M H

    2013-11-01

    To analyze the effects of a single bout and repeated bouts of stretching on indirect markers of exercise-induced muscle damage. A randomized controlled clinical trial at a university human research laboratory was conducted. Fifty-six untrained males were randomly divided into four groups. (I) a single stretching group underwent a single bout of stretching on the quadriceps muscle; (II) an eccentric exercised group underwent eccentric quadriceps muscle contractions until exhaustion; (III) an eccentric exercise group followed by a single bout of stretching; (IV) an eccentric exercised group submitted to repeated bouts of stretching performed immediately and 24, 48, and 72 h post-exercise. Muscle stiffness, muscle soreness, maximal concentric peak torque, and plasma creatine kinase activity were assessed before exercise and 1, 24, 48, 72, and 96 h post-exercise. All exercised groups showed significant reduction in maximal concentric peak torque and significant increases in muscle soreness, muscle stiffness, and plasma creatine kinase. There were no differences between these groups in all assessed variables, with the exception of markers of muscle stiffness, which were significantly lower in the eccentric exercise group followed by single or repeated bouts. The single stretching group showed no change in any assessed variables during the measurement period. Muscle stretching performed after exercise, either as single bout or as repeated bouts, does not influence the levels of the main markers of exercise-induced muscle damage; however, repeated bouts of stretching performed during the days following exercise may have favorable effects on muscle stiffness. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  1. The obesity paradox in men with coronary heart disease and heart failure: the role of muscle mass and leptin.

    Science.gov (United States)

    Wannamethee, S Goya; Shaper, A Gerald; Whincup, Peter H; Lennon, Lucy; Papacosta, Olia; Sattar, Naveed

    2014-01-15

    We have investigated the role of muscle mass, natriuretic peptides and adipokines in explaining the obesity paradox. The obesity paradox relates to the association between obesity and increased survival in patients with coronary heart disease (CHD) or heart failure (HF). Prospective study of 4046 men aged 60-79 years followed up for a mean period of 11 years, during which 1340 deaths occurred. The men were divided according to the presence of doctor diagnosed CHD and HF: (i) no CHD or HF ii), with CHD (no HF) and (iii) with HF. Overweight (BMI 25-9.9 kg/m(2)) and obesity (BMI ≥ 30 kg/m(2)) were associated with lower mortality risk compared to men with normal weight (BMI 18.5-24.9 kg/m(2)) in those with CHD [hazards ratio (HR) 0.71 (0.56,0.91) and 0.77 (0.57,1.04); p=0.04 for trend] and in those with HF [HR 0.57 (0.28,1.16) and 0.41 (0.16,1.09; p=0.04 for trend). Adjustment for muscle mass and NT-proBNP attenuated the inverse association in those with CHD (no HF) [HR 0.78 (0.61,1.01) and 0.96 (0.68,1.36) p=0.60 for trend) but made minor differences to those with HF [p=0.05]. Leptin related positively to mortality in men without HF but inversely to mortality in those with HF; adjustment for leptin abolished the BMI mortality association in men with HF [HR 0.82 (0.31,2.20) and 0.99 (0.27,3.71); p=0.98 for trend]. The lower mortality risk associated with excess weight in men with CHD without HF may be due to higher muscle mass. In men with HF, leptin (possibly reflecting cachexia) explain the inverse association. Copyright © 2013. Published by Elsevier Ireland Ltd.

  2. Comparative statistical mechanics of myosin molecular motors in rat heart, diaphragm and tracheal smooth muscle.

    Science.gov (United States)

    Lecarpentier, Yves; Claes, Victor; Lecarpentier, Edouard; Blanc, François-Xavier; Joseph, Thierry; Geraets, Bart; Krokidis, Xénophon; Hébert, Jean-Louis

    2011-10-01

    Statistical mechanics establishes a link between microscopic properties of matter and its bulk properties. A. Huxley's equations (1957) [1] provide the necessary phenomenological formalism to use statistical mechanics. We compared statistical mechanics in rat diaphragm in tetanus (tet; n=10) and twitch (tw; n=12) modes, in heart in twitch mode (n=20), and in tracheal smooth muscle in tetanus mode (TSM; n=10). This powerful tool makes it possible to determine: (i) statistical entropy (S) which is related to the dispersal of energy and represents a measure of the degree of disorder in muscular system; (ii) thermodynamic force A/T (chemical affinity A and temperature T); (iii) thermodynamic flow (υ); (iv) entropy production rate (A/T×υ), which quantifies irreversible chemical processes generated by myosin crossbridge (CB) molecular motors. All muscles studied operated near equilibrium, i.e., Atype. All studied muscles differed in terms of statistical entropy, chemical affinity, and entropy production rate. Stimulation mode (tet and tw) modulated CB kinetics and statistical mechanics. All muscle types operated near equilibrium and in a stationary linear regime. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  3. [Analogies between heart and respiratory muscle failure. Importance to clinical practice].

    Science.gov (United States)

    Köhler, D

    2009-01-01

    Heart failure is an established diagnosis. Respiratory muscle or ventilatory pump failure, however, is less well known. The latter becomes obvious through hypercapnia, caused by hypoventilation. The respiratory centre tunes into hypercapnea in order to prevent the danger of respiratory muscle overload (hypercapnic ventilatory failure). Hypoventilation will consecutively cause hypoxemia but this will not be responsible for performance limitation. One therefore has to distinguish primary hypoxemia evolving from diseases in the lung parenchyma. Here hypoxemia is the key feature and compensatory hyperventilation usually decreases PaCO2 levels. The cardiac as well as the respiratory pump adapt to an inevitable burden caused by chronic disease. In either case organ muscle mass will increase. If the burden exceeds the range of possible physiological adaptation, compensatory mechanisms will set in that are similar in both instances. During periods of overload either muscle system is mainly fueled by muscular glycogen. In the recovery phase (e. g. during sleep) stores are replenished, which can be recognized by down-regulation of the blood pressure in case of the cardiac pumb or by augmentation of hypercapnia through hypoventilation in case of the respiratory pump. The main function of cardiac and respiratory pump is maintenance of oxygen transport. The human body has developed certain compensatory mechanisms to adapt to insufficient oxygen supply especially during periods of overload. These mechanisms include shift of the oxygen binding curve, expression of respiratory chain isoenzymes capable of producing ATP at lower partial pressures of oxygen and the development of polyglobulia. Medically or pharmacologically the cardiac pump can be unloaded with beta blockers, the respiratory pump by application of inspired oxygen. Newer forms of therapy augment the process of recovery. The heart can be supported through bypass surgery or intravascular pump systems, while respiratory

  4. Attenuated fatigue in slow twitch skeletal muscle during isotonic exercise in rats with chronic heart failure.

    Directory of Open Access Journals (Sweden)

    Morten Munkvik

    Full Text Available During isometric contractions, slow twitch soleus muscles (SOL from rats with chronic heart failure (chf are more fatigable than those of sham animals. However, a muscle normally shortens during activity and fatigue development is highly task dependent. Therefore, we examined the development of skeletal muscle fatigue during shortening (isotonic contractions in chf and sham-operated rats. Six weeks following coronary artery ligation, infarcted animals were classified as failing (chf if left ventricle end diastolic pressure was >15 mmHg. During isoflurane anaesthesia, SOL with intact blood supply was stimulated (1s on 1s off at 30 Hz for 15 min and allowed to shorten isotonically against a constant afterload. Muscle temperature was maintained at 37°C. In resting muscle, maximum isometric force (F(max and the concentrations of ATP and CrP were not different in the two groups. During stimulation, F(max and the concentrations declined in parallel sham and chf. Fatigue, which was evident as reduced shortening during stimulation, was also not different in the two groups. The isometric force decline was fitted to a bi-exponential decay equation. Both time constants increased transiently and returned to initial values after approximately 200 s of the fatigue protocol. This resulted in a transient rise in baseline tension between stimulations, although this effect which was less prominent in chf than sham. Myosin light chain 2s phosphorylation declined in both groups after 100 s of isotonic contractions, and remained at this level throughout 15 min of stimulation. In spite of higher energy demand during isotonic than isometric contractions, both shortening capacity and rate of isometric force decline were as well or better preserved in fatigued SOL from chf rats than in sham. This observation is in striking contrast to previous reports which have employed isometric contractions to induce fatigue.

  5. Twitch and Tetanic Tension during Culture of Mature Xenopus laevis Single Muscle Fibres

    NARCIS (Netherlands)

    Jaspers, R.T.; Feenstra, Hiske; Lee-de Groot, M.B.E.; Huijing, P.A.J.B.M.; van der Laarse, W.J.

    2001-01-01

    Investigation of the mechanisms of muscle adaptation requires independent control of the regulating factors. The aim of the present study was to develop a serum-free medium to culture mature single muscle fibres of Xenopus laevis. As an example, we used the culture system to study adaptation of

  6. Single dose of fluoxetine increases muscle activation in chronic stroke patients.

    NARCIS (Netherlands)

    van Genderen, Hanneke Irene; Nijlant, Juliette M.M.; van Putten, Michel Johannes Antonius Maria; Movig, Kris L.L.; IJzerman, Maarten Joost

    2009-01-01

    Objectives: This pilot study explores the influence of a single dose of fluoxetine (20 mg) on the muscle activation patterns and functional ability of the muscles in the lower part of the arm in chronic stroke patients. Methods: A crossover, placebo-controlled clinical trial was conducted in 10

  7. Radiochromatographic method for determination of macroenergetic phosphorus compounds in the rat heart muscle

    International Nuclear Information System (INIS)

    Wajdowicz, A.

    1980-01-01

    The 32 P was injected intraperitoneally. After 20 min. a part of heart muscle was taken off under anaesthesia from which phosphorus compounds were extracted and separated by means of paper chromatography. Separation was performed on the Whatman 1 paper, in glass tank produced by Shandon by means of method replacing of two direction descending chromatography use together with three solvent system. Identification of nucleotides was conducted in the UV light, besides CP and inorganic phosphorus by means of chemical methods. For the qualitative analysis of separated phosphorus compounds autoradiography was applied. Quantitative analysis was conducted by means of radiogrametric method. Radioactivity for each of examined phosphorus compounds was computed from chromatograms. Radioactive curves were indicated for each stage of chromatography separation. It was found the peaks on the radioactive curves equal the black spots on the autoradiograms and the spots identified with optical test and by the chemical method. This method permits in constant condition absolute separation and quantitative determination of phosphorus compounds in the rat heart muscle. It is relatively simple and more specific than chemical methods. (author)

  8. Noninvasive Measurement of EKG Properties of 3D Artificial Heart Muscle

    Directory of Open Access Journals (Sweden)

    Betsy H. Salazar

    2017-06-01

    Full Text Available Developing and testing a custom fabricated 16-electrode noninvasive direct contact system was necessary to assess the electrical properties of bioengineered heart muscle and to further evaluate the efficacy of cardiac constructs. By culturing neonatal rat primary cardiac cells on a fibrin gel, we constructed 3D artificial heart muscle (3D-AHM, as described in previous studies, which were used in validating this novel system. Electrical and mechanical functional assessment of the tissues was performed, which yielded contractile forces of the tissues, electrical field potential characteristics, and tissue conduction velocities (CV (20–170 cm/s. Immunohistological evaluation revealed the formation of cardiac tissue structures and cardiomyocyte proliferation. EKG data analysis also yielded time delays between signals in the range of 0–38 ms with electrical maps showing some evidence of synchronous contraction within the fabricated tissues. This study demonstrates the effectiveness and practicality of our novel EKG measuring system to acquire distinct electrical metrics of 3D-AHM, which will aid in increasing the viability and applicability of cardiac tissue constructs.

  9. Low Po2 conditions induce reactive oxygen species formation during contractions in single skeletal muscle fibers

    OpenAIRE

    Zuo, Li; Shiah, Amy; Roberts, William J.; Chien, Michael T.; Wagner, Peter D.; Hogan, Michael C.

    2013-01-01

    Contractions in whole skeletal muscle during hypoxia are known to generate reactive oxygen species (ROS); however, identification of real-time ROS formation within isolated single skeletal muscle fibers has been challenging. Consequently, there is no convincing evidence showing increased ROS production in intact contracting fibers under low Po2 conditions. Therefore, we hypothesized that intracellular ROS generation in single contracting skeletal myofibers increases during low Po2 compared wi...

  10. Effects of electric paravertebral muscle relaxation processes in the athletes heart

    Directory of Open Access Journals (Sweden)

    D. V. Syshko

    2013-02-01

    Full Text Available Influence of paravertebrals miorelaxation on electric processes in a heart at sportsmen is studied. Paravertebrals miorelaxation was the complex of exercises in a water environment directed on the decline of tone of paravertebral muscles. Before and after it was used of paravertebrals miorelaxation registered the indexes of electrocardiography at the sportsmen engaged in the Greek-Roman fight (n=22 by football (n=24 and heavy athletics (n=25. It is got, that at the sportsmen of engaged in the Greek -Roman fight after paravertebrals miorelaxation QRS and QT were it was increased, and R-R and PQ went down. At the sportsmen of engaged in heavy athletics HR and PQ went down after paravertebrals miorelaxation, R-R, QRS and QT were it was increased. At the sportsmen of getting busy by football the PQ interval shortened, and QRS and QT has multiplied. Findings testify to the presence of different mechanisms of adaptation of the conducting system of heart in the conditions of influencing of paravertebrals miorelaxation. These distinctions are fated by two basic factors: by the functional being of the cardio-vessels system on the whole and functional being of sine knot and conducting system of heart in particular.

  11. Cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI)

    DEFF Research Database (Denmark)

    Yousaf, Muhammad Naveed; Koppang, Erling Olaf; Skjødt, Karsten

    2012-01-01

    Heart and skeletal muscle inflammation (HSMI) is a disease of marine farmed Atlantic salmon where the pathological changes associated with the disease involve necrosis and an infiltration of inflammatory cells into different regions of the heart and skeletal muscle. The aim of this work...... with the cardiac pathology consisted of mainly CD3(+) T lymphocytes, moderate numbers of macrophages and eosinophilic granulocytes. Proliferative cell nuclear antigen (PCNA) immuno-reaction identified significantly increased nuclear and cytoplasmic staining as well as identifying hypertrophic nuclei. Strong...

  12. Still Heart Encodes a Structural HMT, SMYD1b, with Chaperone-Like Function during Fast Muscle Sarcomere Assembly.

    Directory of Open Access Journals (Sweden)

    Kendal Prill

    Full Text Available The vertebrate sarcomere is a complex and highly organized contractile structure whose assembly and function requires the coordination of hundreds of proteins. Proteins require proper folding and incorporation into the sarcomere by assembly factors, and they must also be maintained and replaced due to the constant physical stress of muscle contraction. Zebrafish mutants affecting muscle assembly and maintenance have proven to be an ideal tool for identification and analysis of factors necessary for these processes. The still heart mutant was identified due to motility defects and a nonfunctional heart. The cognate gene for the mutant was shown to be smyd1b and the still heart mutation results in an early nonsense codon. SMYD1 mutants show a lack of heart looping and chamber definition due to a lack of expression of heart morphogenesis factors gata4, gata5 and hand2. On a cellular level, fast muscle fibers in homozygous mutants do not form mature sarcomeres due to the lack of fast muscle myosin incorporation by SMYD1b when sarcomeres are first being assembled (19hpf, supporting SMYD1b as an assembly protein during sarcomere formation.

  13. Predicting muscle forces during the propulsion phase of single leg triple hop test.

    Science.gov (United States)

    Alvim, Felipe Costa; Lucareli, Paulo Roberto Garcia; Menegaldo, Luciano Luporini

    2018-01-01

    Functional biomechanical tests allow the assessment of musculoskeletal system impairments in a simple way. Muscle force synergies associated with movement can provide additional information for diagnosis. However, such forces cannot be directly measured noninvasively. This study aims to estimate muscle activations and forces exerted during the preparation phase of the single leg triple hop test. Two different approaches were tested: static optimization (SO) and computed muscle control (CMC). As an indirect validation, model-estimated muscle activations were compared with surface electromyography (EMG) of selected hip and thigh muscles. Ten physically healthy active women performed a series of jumps, and ground reaction forces, kinematics and EMG data were recorded. An existing OpenSim model with 92 musculotendon actuators was used to estimate muscle forces. Reflective markers data were processed using the OpenSim Inverse Kinematics tool. Residual Reduction Algorithm (RRA) was applied recursively before running the SO and CMC. For both, the same adjusted kinematics were used as inputs. Both approaches presented similar residuals amplitudes. SO showed a closer agreement between the estimated activations and the EMGs of some muscles. Due to inherent EMG methodological limitations, the superiority of SO in relation to CMC can be only hypothesized. It should be confirmed by conducting further studies comparing joint contact forces. The workflow presented in this study can be used to estimate muscle forces during the preparation phase of the single leg triple hop test and allows investigating muscle activation and coordination. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Single motor unit activity in human extraocular muscles during the vestibulo-ocular reflex

    Science.gov (United States)

    Weber, Konrad P; Rosengren, Sally M; Michels, Rike; Sturm, Veit; Straumann, Dominik; Landau, Klara

    2012-01-01

    Motor unit activity in human eye muscles during the vestibulo-ocular reflex (VOR) is not well understood, since the associated head and eye movements normally preclude single unit recordings. Therefore we recorded single motor unit activity following bursts of skull vibration and sound, two vestibular otolith stimuli that elicit only small head and eye movements. Inferior oblique (IO) and inferior rectus (IR) muscle activity was measured in healthy humans with concentric needle electrodes. Vibration elicited highly synchronous, short-latency bursts of motor unit activity in the IO (latency: 10.5 ms) and IR (14.5 ms) muscles. The activation patterns of the two muscles were similar, but reciprocal, with delayed activation of the IR muscle. Sound produced short-latency excitation of the IO muscle (13.3 ms) in the eye contralateral to the stimulus. Simultaneous needle and surface recordings identified the IO as the muscle of origin of the vestibular evoked myogenic potential (oVEMP) thus validating the physiological basis of this recently developed clinical test of otolith function. Single extraocular motor unit recordings provide a window into neural activity in humans that can normally only be examined using animal models and help identify the pathways of the translational VOR from otoliths to individual eye muscles. PMID:22526888

  15. Association between muscle mass and a single measurement of ...

    African Journals Online (AJOL)

    The relationship between muscle mass and a diagnosis of hypertension in a sample of Korean adults (N=225)was investigated. The participants included adults aged >20 years who visited the S-gu Public Health Centre, Seoul, Korea for a medical check-up in 2011. The Joint National Committee on Prevention, Detection, ...

  16. A method for determination of muscle fiber diameter using single fiber potential (SFP) analysis.

    Science.gov (United States)

    Zalewska, Ewa; Nandedkar, Sanjeev D; Hausmanowa-Petrusewicz, Irena

    2012-12-01

    We have used computer simulation to study the relationship between the muscle fiber diameter and parameters: peak-to-peak amplitude and duration of the negative peak of the muscle fiber action potential. We found that the negative peak duration is useful in the determination of fiber diameter via the diameter dependence of conduction velocity. We have shown a direct link between the underlying physiology and the measurements characterizing single fiber potential. Using data from simulations, a graphical tool and an analytical method to estimate the muscle fiber diameter from the recorded action potential has been developed. The ability to quantify the fiber diameter can add significantly to the single fiber electromyography examination. It may help study of muscle fiber diameter variability and thus compliment the muscle biopsy studies.

  17. New-onset heart failure due to heart muscle disease in childhood: a prospective study in the United kingdom and Ireland.

    Science.gov (United States)

    Andrews, Rachel E; Fenton, Matthew J; Ridout, Deborah A; Burch, Michael

    2008-01-01

    We undertook the first prospective, national, multicenter study to describe the incidence and outcome of heart muscle disease-induced heart failure in children. Data were collected on patients admitted to a hospital through 2003 with a first episode of heart failure in the absence of congenital heart disease. All 17 pediatric cardiac centers in the United Kingdom and Ireland participated. Follow-up data were obtained to a minimum of 1 year. The incidence was 0.87/100,000 population Heart Association class III to IV. Causes of heart failure included dilated cardiomyopathy (50 idiopathic, 8 familial), probable myocarditis (23), occult arrhythmia (7), anthracycline toxicity (5), metabolic disease (4), left ventricular noncompaction (3), and other (4). Overall 1-year survival was 82%, and event (death or transplantation)-free survival was 66%. Regression analysis showed older age and reduced systolic function on admission echocardiogram increased the event risk. Only 8% of event-free survivors (n=69) remained in New York Heart Association class III to IV, but 35 required readmission during the study period, and all but 8 remained on medication. This first national prospective study of new-onset heart failure in children has shown an incidence of 0.87/100,000. Multivariable analysis of survival data indicates a better outcome for younger children and for those with better systolic function at presentation, but overall, one third of children die or require transplantation within 1 year of presentation.

  18. Radiation-induced heart disease due to intrathonacic tumor radiotherapy of a single dose to the rabbits' heart

    International Nuclear Information System (INIS)

    Zhou Weibing; Feng Yan; Chen Jiayi; Luo Quanyong

    2007-01-01

    Objective: To observe the changes of radiation-induced heart disease (RIHD) in the rabbits irradiated in clinical related dose, and to evaluate the apoptosis and hypoxia in the irradiated heart by the new scintigraphic agents of 99 Tc m -HL91 and 99 Tc m -Annexin V of heart SPECT. Methods: Tenty-four New Zealand white rabbits 4-month old and 2-3 kg by weight were divided into two groups. Group 1 (clinical related dose group): 16 irradiated by a single close from 0 to 18 Gy. Group 2 (high dose group): 8 irradiated dose from 22 to 80 Gy. The serum cTnI/CKMB, ECG, and heart SPECT(using 99 Tc m -MIBI, 99 Tc m -HL91 and 99 Tc m -Annexin V as agents) were detected before and after irradiation. The animals were followed for 5 months. Then biopsy of rabbit heart was performed and pathologic examination was made by H.E. stain. Results: In the 16 rabbits of clinical related dose group, none died of RIHD. Whereas 2 rabbits died of RIHD in the high dose group. One died of myocardial infarction and the other of congestive heart failure. According to the Stewart introduced heart lesion grading system, of the clinical close ann, there were moderate in 1 rabbit, minimal in 14; and of the high dose ann, it was severe in 2, marked in 1, moderate in 5. The parallel relation was observed between the ECG results and the pathological changes (χ 2 =0.08, P=0.771). Serum value of cTnI, was elevated at the 12th hour after irradiation reaching the peak and maintained for 4 months. However, it came down in the 5th month. The difference of serum cTnI value before and after radiation was statistically significant. Myocardial perfusion scintigraphy tested by heart SPECT ( 99 Tc m -MIBI) showed defects was present in all irradiated rabbits. The relationship between the defects and radiation dose or between the defects and the real RIHD was uncertain. The SPECT images displayed that 99 Tc m -HL91 and 99m Tc-Annexin V did not accumulate in the irradiated heart. Conclusions: No serious damage is

  19. A mini-overview of single muscle fibre mechanics: the effects of age, inactivity and exercise in animals and humans.

    Science.gov (United States)

    Jee, Hyunseok; Kim, Jong-Hee

    2017-09-05

    Many basic movements of living organisms are dependent on muscle function. Muscle function allows for the coordination and harmonious integrity of movement that is necessary for various biological processes. Gross and fine motor skills are both regulated at the micro-level (single muscle fibre level), controlled by neuronal regulation, and it is therefore important to understand muscle function at both micro- and macro-levels to understand the overall movement of living organisms. Single muscle mechanics and the cellular environment of muscles fundamentally allow for the harmonious movement of our bodies. Indeed, a clear understanding of the functionality of muscle at the micro-level is indispensable for explaining muscular function at the macro-(whole gross muscle) level. By investigating single muscle fibre mechanics, we can also learn how other factors such Ca2+ kinetics, enzyme activity and contractile proteins can contribute to muscle mechanics at the micro- and macro-levels. Further, we can also describe how aging affects the capacity of skeletal muscle cells, as well as how exercise can prevent aging-based sarcopenia and frailty. The purpose of this review is to introduce and summarise the current knowledge of single muscle fibre mechanics in light of aging and inactivity. We then describe how exercise mitigates negative muscle adaptations that occur under those circumstances. In addition, single muscle fibre mechanics in both animal and human models are discussed.

  20. Increased pain and muscle glutamate concentration after single ingestion of monosodium glutamate by myofascial temporomandibular disorders patients.

    Science.gov (United States)

    Shimada, A; Castrillon, E E; Baad-Hansen, L; Ghafouri, B; Gerdle, B; Wåhlén, K; Ernberg, M; Cairns, B E; Svensson, P

    2016-10-01

    A randomized, double-blinded, placebo-controlled study was conducted to investigate if single monosodium glutamate (MSG) administration would elevate muscle/serum glutamate concentrations and affect muscle pain sensitivity in myofascial temporomandibular disorders (TMD) patients more than in healthy individuals. Twelve myofascial TMD patients and 12 sex- and age-matched healthy controls participated in two sessions. Participants drank MSG (150 mg/kg) or NaCl (24 mg/kg; control) diluted in 400 mL of soda. The concentration of glutamate in the masseter muscle, blood plasma and saliva was determined before and after the ingestion of MSG or control. At baseline and every 15 min after the ingestion, pain intensity was scored on a 0-10 numeric rating scale. Pressure pain threshold, pressure pain tolerance (PPTol) and autonomic parameters were measured. All participants were asked to report adverse effects after the ingestion. In TMD, interstitial glutamate concentration was significantly greater after the MSG ingestion when compared with healthy controls. TMD reported a mean pain intensity of 2.8/10 at baseline, which significantly increased by 40% 30 min post MSG ingestion. At baseline, TMD showed lower PPTols in the masseter and trapezius, and higher diastolic blood pressure and heart rate than healthy controls. The MSG ingestion resulted in reports of headache by half of the TMD and healthy controls, respectively. These findings suggest that myofascial TMD patients may be particularly sensitive to the effects of ingested MSG. WHAT DOES THIS STUDY ADD?': Elevation of interstitial glutamate concentration in the masseter muscle caused by monosodium glutamate (MSG) ingestion was significantly greater in myofascial myofascial temporomandibular disorders (TMD) patients than healthy individuals. This elevation of interstitial glutamate concentration in the masseter muscle significantly increased the intensity of spontaneous pain in myofascial TMD patients. © 2016

  1. MLP (muscle LIM protein) as a stress sensor in the heart.

    Science.gov (United States)

    Buyandelger, Byambajav; Ng, Keat-Eng; Miocic, Snjezana; Piotrowska, Izabela; Gunkel, Sylvia; Ku, Ching-Hsin; Knöll, Ralph

    2011-07-01

    Muscle LIM protein (MLP, also known as cysteine rich protein 3 (CSRP3, CRP3)) is a muscle-specific-expressed LIM-only protein. It consists of 194 amino-acids and has been described initially as a factor involved in myogenesis (Arber et al. Cell 79:221-231, 1994). MLP soon became an important model for experimental cardiology when it was first demonstrated that MLP deficiency leads to myocardial hypertrophy followed by a dilated cardiomyopathy and heart failure phenotype (Arber et al. Cell 88:393-403, 1997). At this time, this was the first genetically altered animal model to develop this devastating disease. Interestingly, MLP was also found to be down-regulated in humans with heart failure (Zolk et al. Circulation 101:2674-2677, 2000) and MLP mutations are able to cause hypertrophic and dilated forms of cardiomyopathy in humans (Bos et al. Mol Genet Metab 88:78-85, 2006; Geier et al. Circulation 107:1390-1395, 2003; Hershberger et al. Clin Transl Sci 1:21-26, 2008; Knöll et al. Cell 111:943-955, 2002; Knöll et al. Circ Res 106:695-704, 2010; Mohapatra et al. Mol Genet Metab 80:207-215, 2003). Although considerable efforts have been undertaken to unravel the underlying molecular mechanisms-how MLP mutations, either in model organisms or in the human setting cause these diseases are still unclear. In contrast, only precise knowledge of the underlying molecular mechanisms will allow the development of novel and innovative therapeutic strategies to combat this otherwise lethal condition. The focus of this review will be on the function of MLP in cardiac mechanosensation and we shall point to possible future directions in MLP research.

  2. Primary skeletal muscle myoblasts from chronic heart failure patients exhibit loss of anti-inflammatory and proliferative activity

    NARCIS (Netherlands)

    Sente, T.; Berendoncks, A.M. Van; Jonckheere, A.I.; Rodenburg, R.J.T.; Lauwers, P.; Hoof, V. Van; Wouters, A.; Lardon, F.; Hoymans, V.Y.; Vrints, C.J.

    2016-01-01

    BACKGROUND: Peripheral skeletal muscle wasting is a common finding with adverse effects in chronic heart failure (HF). Whereas its clinical relevance is beyond doubt, the underlying pathophysiological mechanisms are not yet fully elucidated. We aimed to introduce and characterize the primary culture

  3. Quantitative analysis of single muscle fibre action potentials recorded at known distances

    NARCIS (Netherlands)

    Albers, B.A.; Put, J.H.M.; Wallinga, W.; Wirtz, P.

    1989-01-01

    In vivo records of single fibre action potentials (SFAPs) have always been obtained at unknown distance from the active muscle fibre. A new experimental method has been developed enabling the derivation of the recording distance in animal experiments. A single fibre is stimulated with an

  4. Single sodium channels from human ventricular muscle in planar lipid bilayers

    NARCIS (Netherlands)

    Wartenberg, H. C.; Wartenberg, J. P.; Urban, B. W.

    2001-01-01

    Sodium channels from human ventricular muscle membrane vesicles were incorporated into planar lipid bilayers and the steady-state behavior of single sodium channels were examined in the presence of batrachotoxin. In symmetrical 500 mM NaCl the averaged single channel conductance was 24.7 +/- 1.3 pS

  5. Respiratory muscle strength effect on linear and nonlinear heart rate variability parameters in COPD patients

    Directory of Open Access Journals (Sweden)

    Goulart CL

    2016-07-01

    Full Text Available Cássia Da Luz Goulart,1 Julio Cristiano Simon,1 Paloma De Borba Schneiders,1 Elisabete Antunes San Martin,1 Ramona Cabiddu,2 Audrey Borghi-Silva,2 Renata Trimer,2 Andréa Lúcia Gonçalves da Silva1 1Course of Physiotherapy, Department of Health and Physical Education, University of Santa Cruz do Sul (UNISC, Santa Cruz do Sul, Rio Grande do Sul, Brazil; 2Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Federal University of São Carlos (UFSCar, São Carlos, São Paulo, Brazil Introduction: Chronic obstructive pulmonary disease (COPD is recognized as a multisystemic inflammatory disease associated with extrapulmonary comorbidities, including respiratory muscle weakness and cardiovascular and cardiac autonomic regulation disorders. We investigated whether alterations in respiratory muscle strength (RMS would affect cardiac autonomic modulation in COPD patients. Methods: This study was a cross-sectional study done in ten COPD patients affected by moderate to very severe disease. The heart rate variability (HRV signal was recorded using a Polar cardiofrequencimeter at rest in the sitting position (10 minutes and during a respiratory sinus arrhythmia maneuver (RSA-M; 4 minutes. Linear analysis in the time and frequency domains and nonlinear analysis were performed on the recorded signals. RMS was assessed using a digital manometer, which provided the maximum inspiratory pressure (Pimax and the maximum expiratory pressure (Pemax. Results: During the RSA-M, patients presented an HRV power increase in the low-frequency band (LFnu (46.9±23.7 vs 75.8±27.2; P=0.01 and a decrease in the high-frequency band (HFnu (52.8±23.5 vs 24.0±27.0; P=0.01 when compared to the resting condition. Significant associations were found between RMS and HRV spectral indices: Pimax and LFnu (r=-0.74; P=0.01; Pimax and HFnu (r=0.74; P=0.01; Pemax and LFnu (r=-0.66; P=0.01; Pemax and HFnu (r=0.66; P=0.03; between Pemax and sample entropy (r

  6. Management of single-ventricle patients with Berlin Heart EXCOR Ventricular Assist Device: single-center experience.

    Science.gov (United States)

    Mackling, Tracey; Shah, Tejas; Dimas, Vivian; Guleserian, Kristine; Sharma, Mahesh; Forbess, Joseph; Ardura, Monica; Gross-Toalson, Jami; Lee, Ying; Journeycake, Janna; Barnes, Aliessa

    2012-06-01

    There are minimal data regarding chronic management of single-ventricle ventricular assist device (VAD) patients. This study aims to describe our center's multidisciplinary team management of single-ventricle patients supported long term with the Berlin Heart EXCOR Pediatric VAD. Patient #1 was a 4-year-old with double-outlet right ventricle with aortic atresia, L-looped ventricles, and heart block who developed heart failure 1 year after Fontan. She initially required extracorporeal membrane oxygenation support and was transitioned to Berlin Heart systemic VAD. She was supported for 363 days (cardiac intensive care unit [CICU] 335 days, floor 28 days). The postoperative course was complicated by intermittent infection including methicillin-resistant Staphylococcus aureus, intermittent hepatic and renal insufficiencies, and transient antithrombin, protein C, and protein S deficiencies resulting in multiple thrombi. She had a total of five pump changes over 10 months. Long-term medical management included anticoagulation with enoxaparin, platelet inhibition with aspirin and dipyridamole, and antibiotic prophylaxis using trimethoprim/sulfamethoxazole. She developed sepsis of unknown etiology and subsequently died from multiorgan failure. Patient #2 was a 4-year-old with hypoplastic left heart syndrome who developed heart failure 2 years after bidirectional Glenn shunt. At systemic VAD implantation, he was intubated with renal insufficiency. Post-VAD implantation, his renal insufficiency resolved, and he was successfully extubated to daytime nasal cannula and biphasic positive airway pressure at night. He was supported for 270 days (CICU 143 days, floor 127 days). The pump was upsized to a 50-mL pump in May 2011 for increased central venous pressures (29 mm Hg). Long-term medical management included anticoagulation with warfarin and single-agent platelet inhibition using dipyridamole due to aspirin resistance. He developed increased work of breathing requiring

  7. Expression of nuclear factor of activated T cells (NFAT) and downstream muscle-specific proteins in ground squirrel skeletal and heart muscle during hibernation.

    Science.gov (United States)

    Zhang, Yichi; Storey, Kenneth B

    2016-01-01

    The thirteen-lined ground squirrel (Ictidomys tridecemlineatus) undergoes remarkable adaptive changes during hibernation. Interestingly, skeletal muscle remodelling occurs during the torpor-arousal cycle of hibernation to prevent net muscle loss despite inactivity. Reversible cardiomyocyte hypertrophy occurs in cardiac muscle, allowing the heart to preserve cardiac output during hibernation, while avoiding chronic maladaptive hypertrophy post-hibernation. We propose that calcium signalling proteins [calcineurin (Cn), calmodulin (CaM), and calpain], the nuclear factor of activated T cell (NFAT) family of transcription factors, and the NFAT targets myoferlin and myomaker contribute significantly to adaptations taking place in skeletal and cardiac muscle during hibernation. Protein-level analyses were performed over several conditions: euthermic room temperature (ER), euthermic cold room (EC), entrance into (EN), early (ET), and late torpor (LT) time points, in addition to early (EA), interbout (IA), and late arousal (LA) time points using immunoblotting and DNA-protein interaction (DPI) enzyme-linked immunosorbent assay (ELISAs). In skeletal and cardiac muscle, NFATc2 protein levels were elevated during torpor. NFATc4 increased throughout the torpor-arousal cycle in both tissues, and NFATc1 showed this trend in cardiac muscle only. NFATc3 showed an elevation in DNA-binding activity but not expression during torpor. Myoferlin protein levels dramatically increased during torpor in both skeletal and cardiac muscle. Myomaker levels also increased significantly in cardiac muscle during torpor. Cardiac Cn levels remained stable, whereas CaM and calpain decreased throughout the torpor-arousal cycle. Activation and/or upregulation of NFATc2, c3, myoferlin, and myomaker at torpor could be part of a stress-response mechanism to preserve skeletal muscle mass, whereas CaM and calpain appear to initiate the rapid reversal of cardiac hypertrophy during arousal through

  8. Single- and multiple-set resistance training improves skeletal and respiratory muscle strength in elderly women.

    Science.gov (United States)

    Abrahin, Odilon; Rodrigues, Rejane P; Nascimento, Vanderson C; Da Silva-Grigoletto, Marzo E; Sousa, Evitom C; Marçal, Anderson C

    2014-01-01

    Aging involves a progressive reduction of respiratory muscle strength as well as muscle strength. Compare the effects of resistance training volume on the maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), functional performance, and muscle strength in elderly women. Thirty elderly women were randomly assigned to a group performing either single sets (1-SET) or three sets (3-SET) of exercises. The sit-to-stand test, MIP, MEP, and muscle strength were assessed before and after 24 training sessions. Progressive resistance training was performed two times per week for a total of 8-12 repetitions, using the main muscle groups of the upper and lower limbs. The main results showed that the participants significantly increased their MEP (Ptraining sessions, muscle strength also significantly increased (Ptraining programs increased MIP, MEP, muscle strength, and sit-to-stand test performance in elderly women after 24 sessions of training. In conclusion, our results suggested that elderly women who are not in the habit of physical activity may start with single-set resistance training programs as a short-term strategy for the maintenance of health.

  9. Effects of ageing on single muscle fibre contractile function following short-term immobilisation

    DEFF Research Database (Denmark)

    Hvid, Lars G; Ortenblad, Niels; Aagaard, Per

    2011-01-01

    Very little attention has been given to the combined effects of healthy ageing and short-term disuse on the contractile function of human single muscle fibres. Therefore, the present study investigated the effects of 2 weeks of lower limb cast immobilisation (i.e. disuse) on selected contractile.......05), respectively. In conclusion, 2 weeks of lower limb immobilisation caused greater impairments in single muscle fibre force and specific force in MHC IIa than MHC I fibres independently of age. In contrast, immobilisation-induced changes in Ca(2+) sensitivity that were dependent on age and MHC isoform....... properties of single muscle fibres (n = 378) from vastus lateralis of nine young (24 ± 1 years) and eight old (67 ± 2 years) healthy men with comparable levels of physical activity. Prior to immobilisation, MHC IIa fibres produced higher maximum Ca(2+)-activated force (approx. 32%) and specific force (approx...

  10. Excitation-calcium release uncoupling in aged single human skeletal muscle fibers.

    Science.gov (United States)

    Delbono, O; O'Rourke, K S; Ettinger, W H

    1995-12-01

    The biological mechanisms underlying decline in muscle power and fatigue with age are not completely understood. The contribution of alterations in the excitation-calcium release coupling in single muscle fibers was explored in this work. Single muscle fibers were voltage-clamped using the double Vaseline gap technique. The samples were obtained by needle biopsy of the vastus lateralis (quadriceps) from 9 young (25-35 years; 25.9 +/- 9.1; 5 female and 4 male) and 11 old subjects (65-75 years; 70.5 +/- 2.3; 6 f, 5 m). Data were obtained from 36 and 39 fibers from young and old subjects, respectively. Subjects included in this study had similar physical activity. Denervated and slow-twitch muscle fibers were excluded from this study. A significant reduction of maximum charge movement (Qmax) and DHP-sensitive Ca current were recorded in muscle fibers from the 65-75 group. Qmax values were 7.6 +/- 0.9 and 3.2 +/- 0.3 nC/muF for young and old muscle fibers, respectively (P charge inactivation or interconversion (charge 1 to charge 2) were found. The peak Ca current was (-)4.7 +/- 0.08 and (-)2.15 +/- 0.11 muA/muF for young and old fibers, respectively (P muscle fibers, respectively. Caffeine (0.5 mM) induced potentiation of the peak calcium transient in both groups. The decrease in the voltage-/Ca-dependent Ca release ratio in old fibers (0.18 +/- 0.02) compared to young fibers (0.47 +/- 0.03) (P skeletal muscle and, the reduction of Ca release is due to DHPR-ryanodine receptor uncoupling in fast-twitch fibers. These alterations can account, at least partially for the skeletal muscle function impairment associated with aging.

  11. Effects of ageing on single muscle fibre contractile function following short-term immobilisation

    DEFF Research Database (Denmark)

    Hvid, Lars G; Ørtenblad, Niels; Aagaard, Per

    2011-01-01

    Very little attention has been given to the combined effect of healthy ageing and short-term disuse on the contractile function of human single muscle fibres. Therefore, the present study investigated the effects of 2 weeks of lower limb cast immobilisation (i.e. disuse) on selected contractile...... properties of single muscle fibres (n=378) from vastus lateralis of 9 young (24 ± 1 years) and 8 old (67 ± 2 years) healthy men with comparable levels of physical activity. Prior to immobilisation, MHC IIa fibres produced higher maximum Ca2+-activated force (approx. 32%) and specific force (approx. 33......%) and had lower Ca2+ sensitivity than MHC I fibres (p...

  12. Quantitative evaluation of muscle synergy models: a single-trial task decoding approach

    Directory of Open Access Journals (Sweden)

    Ioannis eDelis

    2013-02-01

    Full Text Available Muscle synergies, i.e. invariant coordinated activations of groups of muscles, have been proposed as building blocks that the central nervous system uses to construct the patterns of muscle activity utilized for executing movements. Several efficient dimensionality reduction algorithms that extract putative synergies from electromyographic (EMG signals have been developed. Typically, the quality of synergy decompositions is assessed by computing the variance accounted for (VAF. Yet, little is known about the extent to which the combination of those synergies encodes task-discriminating variations of muscle activity in individual trials. To address this question, here we conceive and develop a novel computational framework to evaluate muscle synergy decompositions in task space. Unlike previous methods considering the total variance of muscle patterns (VAF based metrics, our approach focuses on variance discriminating execution of different tasks. The procedure is based on single-trial task decoding from muscle synergy activation features. The task decoding based metric evaluates quantitatively the mapping between synergy recruitment and task identification and automatically determines the minimal number of synergies that captures all the task-discriminating variability in the synergy activations. In this paper, we first validate the method on plausibly simulated EMG datasets. We then show that it can be applied to different types of muscle synergy decomposition and illustrate its applicability to real data by using it for the analysis of EMG recordings during an arm pointing task. We find that time-varying and synchronous synergies with similar number of parameters are equally efficient in task decoding, suggesting that in this experimental paradigm they are equally valid representations of muscle synergies. Overall, these findings stress the effectiveness of the decoding metric in systematically assessing muscle synergy decompositions in task

  13. Quantitative evaluation of muscle synergy models: a single-trial task decoding approach.

    Science.gov (United States)

    Delis, Ioannis; Berret, Bastien; Pozzo, Thierry; Panzeri, Stefano

    2013-01-01

    Muscle synergies, i.e., invariant coordinated activations of groups of muscles, have been proposed as building blocks that the central nervous system (CNS) uses to construct the patterns of muscle activity utilized for executing movements. Several efficient dimensionality reduction algorithms that extract putative synergies from electromyographic (EMG) signals have been developed. Typically, the quality of synergy decompositions is assessed by computing the Variance Accounted For (VAF). Yet, little is known about the extent to which the combination of those synergies encodes task-discriminating variations of muscle activity in individual trials. To address this question, here we conceive and develop a novel computational framework to evaluate muscle synergy decompositions in task space. Unlike previous methods considering the total variance of muscle patterns (VAF based metrics), our approach focuses on variance discriminating execution of different tasks. The procedure is based on single-trial task decoding from muscle synergy activation features. The task decoding based metric evaluates quantitatively the mapping between synergy recruitment and task identification and automatically determines the minimal number of synergies that captures all the task-discriminating variability in the synergy activations. In this paper, we first validate the method on plausibly simulated EMG datasets. We then show that it can be applied to different types of muscle synergy decomposition and illustrate its applicability to real data by using it for the analysis of EMG recordings during an arm pointing task. We find that time-varying and synchronous synergies with similar number of parameters are equally efficient in task decoding, suggesting that in this experimental paradigm they are equally valid representations of muscle synergies. Overall, these findings stress the effectiveness of the decoding metric in systematically assessing muscle synergy decompositions in task space.

  14. The effects of surface condition on abdominal muscle activity during single-legged hold exercise.

    Science.gov (United States)

    Ha, Sung-min; Oh, Jae-seop; Jeon, In-cheol; Kwon, Oh-yun

    2015-02-01

    To treat low-back pain, various spinal stability exercises are commonly used to improve trunk muscle function and strength. Because human movement for normal daily activity occurs in multi-dimensions, the importance of exercise in multi-dimensions or on unstable surfaces has been emphasized. Recently, a motorized rotating platform (MRP) for facilitating multi-dimensions dynamic movement was introduced for clinical use. However, the abdominal muscle activity with this device has not been reported. The purpose of this study was to compare the abdominal muscle activity (rectus abdominis, external and internal oblique muscles) during an active single-leg-hold (SLH) exercise on a floor (stable surface), foam roll, and motorized rotating platform (MRP). Thirteen healthy male subjects participated in this study. Using electromyography, the abdominal muscle activity was measured while the subjects performed SLH exercises on floor (stable surface), foam roll, and MRP. There were significant differences in the abdominal muscle activities among conditions (P.05) (Fig. 2). After the Bonferroni correction, however, no significant differences among conditions remained, except for differences in both side IO muscle activity between the floor and foam roll conditions (padjactivities of both side of RA and IO, and Rt. EO compared to floor condition. However, there were no significant differences in abdominal muscles activity in the multiple comparison between conditions (mean difference were smaller than the standard deviation in the abdominal muscle activities) (padj>0.017), except for differences in both side IO muscle activity between the floor (stable surface) and foam roll (padj<0.017) (effect size: 0.79/0.62 (non-supporting/supporting leg) for foam-roll versus floor). Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The effects of resistance training on muscle strength, quality of life and aerobic capacity in patients with chronic heart failure - A meta-analysis.

    Science.gov (United States)

    Giuliano, Catherine; Karahalios, Amalia; Neil, Christopher; Allen, Jason; Levinger, Itamar

    2017-01-15

    Resistance training (RT) has been utilised to target muscle dysfunction associated with Chronic Heart Failure (CHF). However, there is limited meta-analysis evidence to support its use as a standalone therapy. This meta-analysis examined the effects of RT on muscle strength (one repetition maximum, 1RM and Peak Torque), aerobic capacity (VO 2peak and 6min walk distance) and quality of life (QoL) in patients with CHF. We searched Medline, EMBASE, Cochrane and CINAHL for studies published up to July 2016, combining terms related to the population (eg, heart failure, CHF) with terms for the intervention (eg, resistance, strength training) and the outcomes (eg, QoL, VO 2 peak , strength, aerobic capacity). Ten studies including 240 participants were included in our meta-analysis (aged 48-76years, Ejection Fraction 18-37%). Training duration ranged from 8 to 24weeks and intensity up to 80% of 1RM. RT increased 1RM (standardised change score=0.60; 95% Confidence Interval: 0.43, 0.77) but not strength measured via peak torque at 60°/s - 1 and 180°/s - 1 . RT increased VO 2peak (CSMD: 2.71ml/kg/min; 1.96, 3.45) and QoL (CSMD: -5.71; -9.85, -1.56). RT as a single intervention can increase muscle strength, aerobic capacity and QoL in patients with CHF and may offer an alternative approach, particularly for those unable to participate in aerobic training. The effect of RT on muscle strength is mainly during slow controlled movements and not during rapid movements. Older adults and patients with advanced CHF are underrepresented in RT trials and future studies should seek to optimise their inclusion. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. A single dose of dark chocolate increases parasympathetic modulation and heart rate variability in healthy subjects

    Directory of Open Access Journals (Sweden)

    Ana Amélia Machado DUARTE

    Full Text Available ABSTRACT Objective: The aim of this study was to investigate the acute effect of a single dose of dark chocolate (70% cocoa on blood pressure and heart rate variability. Methods: Thirty-one healthy subjects (aged 18-25 years; both sexes were divided into two groups: 10 subjects in the white chocolate (7.4 g group and 21 in the dark chocolate (10 g group; measurements were performed at the university's physiology lab. An electrocardiogram measured the sympathovagal balance by spectral and symbolic analysis. Results: A single dose of dark chocolate significantly reduced systolic blood pressure and heart rate. After consuming 10 g of dark chocolate, significant increases were observed for heart rate variability, standard deviation of RR intervals standard deviation of all NN intervals, square root of the mean squared differences between adjacent normal RR intervals root mean square of successive differences, and an increase in the high frequency component in absolute values, representing the parasympathetic modulation. Conclusion: In conclusion the importance of our results lies in the magnitude of the response provoked by a single dose of cocoa. Just 10 g of cocoa triggered a significant increase in parasympathetic modulation and heart rate variability. These combined effects can potentially increase life expectancy because a reduction in heart rate variability is associated with several cardiovascular diseases and higher mortality.

  17. Motion-insensitive determination of B1+ amplitudes based on the bloch-siegert shift in single voxels of moving organs including the human heart.

    Science.gov (United States)

    Dokumaci, Ayse Sila; Pouymayou, Bertrand; Kreis, Roland; Boesch, Chris

    2016-05-01

    To reliably determine the amplitude of the transmit radiofrequency ( B1+) field in moving organs like the liver and heart, where most current techniques are usually not feasible. B1+ field measurement based on the Bloch-Siegert shift induced by a pair of Fermi pulses in a double-triggered modified Point RESolved Spectroscopy (PRESS) sequence with motion-compensated crusher gradients has been developed. Performance of the sequence was tested in moving phantoms and in muscle, liver, and heart of six healthy volunteers each, using different arrangements of transmit/receive coils. B1+ determination in a moving phantom was almost independent of type and amplitude of the motion and agreed well with theory. In vivo, repeated measurements led to very small coefficients of variance (CV) if the amplitude of the Fermi pulse was chosen above an appropriate level (CV in muscle 0.6%, liver 1.6%, heart 2.3% with moderate amplitude of the Fermi pulses and 1.2% with stronger Fermi pulses). The proposed sequence shows a very robust determination of B1+ in a single voxel even under challenging conditions (transmission with a surface coil or measurements in the heart without breath-hold). © 2015 Wiley Periodicals, Inc.

  18. Silver nanoparticles administered to chicken affect VEGFA and FGF2 gene expression in breast muscle and heart

    DEFF Research Database (Denmark)

    Hotowy, Anna Malgorzata; Sawosz, Ewa; Pineda, Lane Manalili

    2012-01-01

    chickens as a water solution in two concentrations (10 and 20 ppm). After dissection of the birds, breast muscles and hearts were collected. Gene expression of FGF2 and VEGF on the mRNA and protein levels were evaluated using qPCR and ELISA methods. The results for gene expression in breast muscle revealed...... of these genes may lead to histological changes, but this needs to be proven using histological and immunohistochemical examination of tissues. In general, we showed that AgNano application in poultry feeding can influence the expression of FGF2 and VEGFA genes on the mRNA and protein levels in growing chicken....

  19. Muscle power failure in mobility-limited older adults: preserved single fiber function despite lower whole muscle size, quality and rate of neuromuscular activation.

    Science.gov (United States)

    Reid, Kieran F; Doros, Gheorghe; Clark, David J; Patten, Carolynn; Carabello, Robert J; Cloutier, Gregory J; Phillips, Edward M; Krivickas, Lisa S; Frontera, Walter R; Fielding, Roger A

    2012-06-01

    This study investigated the physiological and gender determinants of the age-related loss of muscle power in 31 healthy middle-aged adults (aged 40-55 years), 28 healthy older adults (70-85 years) and 34 mobility-limited older adults (70-85 years). We hypothesized that leg extensor muscle power would be significantly lower in mobility-limited elders relative to both healthy groups and sought to characterize the physiological mechanisms associated with the reduction of muscle power with aging. Computed tomography was utilized to assess mid-thigh body composition and calculate specific muscle power and strength. Surface electromyography was used to assess rate of neuromuscular activation and muscle biopsies were taken to evaluate single muscle fiber contractile properties. Peak muscle power, strength, muscle cross-sectional area, specific muscle power and rate of neuromuscular activation were significantly lower among mobility-limited elders compared to both healthy groups (P ≤ 0.05). Mobility-limited older participants had greater deposits of intermuscular adipose tissue (P mobility-limited elders relative to both healthy groups. Male gender was associated with greater decrements in peak and specific muscle power among mobility-limited participants. Impairments in the rate of neuromuscular activation and concomitant reductions in muscle quality are important physiological mechanisms contributing to muscle power deficits and mobility limitations. The dissociation between age-related changes at the whole muscle and single fiber level suggest that, even among older adults with overt mobility problems, contractile properties of surviving muscle fibers are preserved in an attempt to maintain overall muscle function.

  20. Isolation and individual electrical stimulation of single smooth-muscle cells from the urinary bladder of the pig

    NARCIS (Netherlands)

    J.J. Glerum (Jacobus); R. van Mastrigt (Ron); J.C. Romijn (Johannes); D.J. Griffiths (Derek)

    1987-01-01

    textabstractIn contrast to striated muscle, measurements on strips of smooth muscle cannot be uniquely interpreted in terms of an array of contractile units. Therefore scaling down to the single-cell level is necessary to gain detailed understanding of the contractile process in this type of muscle.

  1. Living with half a heart - experiences of young adults with single ventricle physiology

    DEFF Research Database (Denmark)

    Overgaard, Dorthe; King, Catriona; Christensen, Rie F

    2013-01-01

    BACKGROUND AND RESEARCH OBJECTIVE:: Approximately 3% of children with congenital heart disease born in Denmark have single ventricle physiology (SVP). In previous decades, these children did not survive into adulthood. However, because of new surgical techniques and improved medical care, they now...

  2. Comparative cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD)

    DEFF Research Database (Denmark)

    Yousaf, Muhammad Naveed; Koppang, Erling Olaf; Skjødt, Karsten

    2013-01-01

    muscle, liver and pancreas. The main findings of these diseases are necrosis and inflammatory cells infiltrates affecting different regions of the heart. In order to better characterize the cardiac pathology, study of the inflammatory cell characteristics and cell cycle protein expression was undertaken......The heart is considered the powerhouse of the cardiovascular system. Heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD) are cardiac diseases of marine farmed Atlantic salmon (Salmo salar) which commonly affect the heart in addition to the skeletal...

  3. Immunohistochemical detection of piscine reovirus (PRV in hearts of Atlantic salmon coincide with the course of heart and skeletal muscle inflammation (HSMI

    Directory of Open Access Journals (Sweden)

    Finstad Øystein

    2012-04-01

    Full Text Available Abstract Aquaculture is the fastest growing food production sector in the world. However, the increased production has been accompanied by the emergence of infectious diseases. Heart and skeletal muscle inflammation (HSMI is one example of an emerging disease in farmed Atlantic salmon (Salmo salar L. Since the first recognition as a disease entity in 1999 it has become a widespread and economically important disease in Norway. The disease was recently found to be associated with infection with a novel reovirus, piscine reovirus (PRV. The load of PRV, examined by RT-qPCR, correlated with severity of HSMI in naturally and experimentally infected salmon. The disease is characterized by epi-, endo- and myocarditis, myocardial necrosis, myositis and necrosis of the red skeletal muscle. The aim of this study was to investigate the presence of PRV antigens in heart tissue of Atlantic salmon and monitor the virus distribution in the heart during the disease development. This included target cell specificity, viral load and tissue location during an HSMI outbreak. Rabbit polyclonal antisera were raised against putative PRV capsid proteins μ1C and σ1 and used in immunohistochemical analysis of archived salmon heart tissue from an experimental infection. The results are consistent with the histopathological changes of HSMI and showed a sequential staining pattern with PRV antigens initially present in leukocyte-like cells and subsequently in cardiomyocytes in the heart ventricle. Our results confirm the association between PRV and HSMI, and strengthen the hypothesis of PRV being the causative agent of HSMI. Immunohistochemical detection of PRV antigens will be beneficial for the understanding of the pathogenesis of HSMI as well as for diagnostic purposes.

  4. Influence of inspiratory muscle weakness on inspiratory muscle training responses in chronic heart failure patients: a systematic review and meta-analysis.

    Science.gov (United States)

    Montemezzo, Dayane; Fregonezi, Guilherme Augusto; Pereira, Danielle Aparecida; Britto, Raquel Rodrigues; Reid, W Darlene

    2014-07-01

    To determine whether the impact of inspiratory muscle weakness on inspiratory muscle training (IMT) affects inspiratory function and exercise capacity in chronic heart failure (CHF) patients. Electronic searches were performed using the Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, Cochrane Systematic Review, Embase, MEDLINE, and Physiotherapy Evidence Database (PEDro) databases up to August 2013. Articles were included if participants had CHF and were >18 years old; the design was a randomized controlled trial; intervention was IMT; measurements were of inspiratory muscle function or exercise capacity; and the articles were published in English, Portuguese, or Spanish. Of the 1455 articles identified in the database searches, 9 studies met the inclusion criteria. Two independent reviewers selected and extracted information from articles and assessed the quality of the studies using the PEDro scale. The 2 reviewers discussed disagreements until consensus was achieved. Meta-analyses compared IMT with controls/sham for maximal inspiratory pressure, sustained maximal inspiratory pressure, 6-minute walk distance, peak oxygen consumption, and minute ventilation after IMT. Subgroup analyses compared those with and without muscle weakness. CHF with inspiratory muscle weakness showed greater gains in the 6-minute walk distance and peak oxygen consumption compared with those with normative maximal inspiratory pressure. The mean quality analysis score was 7.1, and scores ranged from 6 to 10. The results emphasize the importance of evaluating the inspiratory muscles to identify patients with CHF and inspiratory muscle weakness; subgroup that showed better results after IMT. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Sensitivity of the amplitude of the single muscle fibre action potential to microscopic volume conduction parameters

    NARCIS (Netherlands)

    Alberts, B.A.; Rutten, Wim; Wallinga, W.; Boom, H.B.K.

    1988-01-01

    A microscopic model of volume conduction was applied to examine the sensitivity of the single muscle fibre action potential to variations in parameters of the source and of the volume conductor, such as conduction velocity, intracellular conductivity and intracellular volume fraction. The model

  6. Single sodium channels from human skeletal muscle in planar lipid bilayers: characterization and response to pentobarbital

    NARCIS (Netherlands)

    Wartenberg, Hans C.; Urban, Bernd W.

    2004-01-01

    PURPOSE: To investigate the response to general anesthetics of different sodium-channel subtypes, we examined the effects of pentobarbital, a close thiopental analogue, on single sodium channels from human skeletal muscle and compared them to existing data from human brain and human ventricular

  7. Mechanical properties of mammalian single smooth muscle cells. I. A low cost large range microforce transducer.

    NARCIS (Netherlands)

    J.J. Glerum (Jacobus); R. van Mastrigt (Ron)

    1990-01-01

    textabstractA transducer has been developed for measuring the minute forces generated during isometric contractions (1.0-10.0 microN) of single smooth muscle cells from the pig urinary bladder and the human uterus. In addition to its high sensitivity, resolution and stability (100 mV microN-1, and

  8. Heart and skeletal muscle inflammation of farmed salmon is associated with infection with a novel reovirus.

    Directory of Open Access Journals (Sweden)

    Gustavo Palacios

    2010-07-01

    Full Text Available Atlantic salmon (Salmo salar L. mariculture has been associated with epidemics of infectious diseases that threaten not only local production, but also wild fish coming into close proximity to marine pens and fish escaping from them. Heart and skeletal muscle inflammation (HSMI is a frequently fatal disease of farmed Atlantic salmon. First recognized in one farm in Norway in 1999, HSMI was subsequently implicated in outbreaks in other farms in Norway and the United Kingdom. Although pathology and disease transmission studies indicated an infectious basis, efforts to identify an agent were unsuccessful. Here we provide evidence that HSMI is associated with infection with piscine reovirus (PRV. PRV is a novel reovirus identified by unbiased high throughput DNA sequencing and a bioinformatics program focused on nucleotide frequency as well as sequence alignment and motif analyses. Formal implication of PRV in HSMI will require isolation in cell culture and fulfillment of Koch's postulates, or prevention or modification of disease through use of specific drugs or vaccines. Nonetheless, as our data indicate that a causal relationship is plausible, measures must be taken to control PRV not only because it threatens domestic salmon production but also due to the potential for transmission to wild salmon populations.

  9. The effect of a single dose of morphine on muscle fatigue indices in male rats

    Directory of Open Access Journals (Sweden)

    Sedigheh Amiresmaili

    2016-09-01

    Full Text Available Background and Aim: Endogenous opioids and addictive opiate drugs change many body functions. . Previous studies have referred to the effects of morphine on smooth and pulmonary muscles ., but the  effects of opioids on skeletal muscles is not known well. Thus, the current study aimed at assessing the effect of a single dose of morphine on muscle fatigue in male rats. Materials and Methods: In this experimental study, 40 male Wistar rats weighing 220-270 g were randomly divided into four equal groups: control (the mice were kept in their cages and received food and water, morphine receiving group, fatigue group (the mice in this group were kept running on  a treadmill . for120 minutes at a rate of 20 meters per minute, and morphine plus fatigue group. At the end of the experiments, blood samples were obtained from the corner of their eyes and were sent to the laboratory for measurement of muscle fatigue indexes including lactate dehydrogenase (LDH and creatine phosphokinase (CPK. Results: Administration of morphine to the fatigue group decreased running time compared with the control group (P=0.009. Furthermore, administration of morphine to the fatigue group significantly increased serum levels of LDH (P=0.009 and CPK (P=0.008. Conclusion: The present study showed that administration of a single dose of morphine in rats increases muscle fatigue biomarkers (LDH, CPK.

  10. Drosophila small heat shock protein CryAB ensures structural integrity of developing muscles, and proper muscle and heart performance.

    Science.gov (United States)

    Wójtowicz, Inga; Jabłońska, Jadwiga; Zmojdzian, Monika; Taghli-Lamallem, Ouarda; Renaud, Yoan; Junion, Guillaume; Daczewska, Malgorzata; Huelsmann, Sven; Jagla, Krzysztof; Jagla, Teresa

    2015-03-01

    Molecular chaperones, such as the small heat shock proteins (sHsps), maintain normal cellular function by controlling protein homeostasis in stress conditions. However, sHsps are not only activated in response to environmental insults, but also exert developmental and tissue-specific functions that are much less known. Here, we show that during normal development the Drosophila sHsp CryAB [L(2)efl] is specifically expressed in larval body wall muscles and accumulates at the level of Z-bands and around myonuclei. CryAB features a conserved actin-binding domain and, when attenuated, leads to clustering of myonuclei and an altered pattern of sarcomeric actin and the Z-band-associated actin crosslinker Cheerio (filamin). Our data suggest that CryAB and Cheerio form a complex essential for muscle integrity: CryAB colocalizes with Cheerio and, as revealed by mass spectrometry and co-immunoprecipitation experiments, binds to Cheerio, and the muscle-specific attenuation of cheerio leads to CryAB-like sarcomeric phenotypes. Furthermore, muscle-targeted expression of CryAB(R120G), which carries a mutation associated with desmin-related myopathy (DRM), results in an altered sarcomeric actin pattern, in affected myofibrillar integrity and in Z-band breaks, leading to reduced muscle performance and to marked cardiac arrhythmia. Taken together, we demonstrate that CryAB ensures myofibrillar integrity in Drosophila muscles during development and propose that it does so by interacting with the actin crosslinker Cheerio. The evidence that a DRM-causing mutation affects CryAB muscle function and leads to DRM-like phenotypes in the fly reveals a conserved stress-independent role of CryAB in maintaining muscle cell cytoarchitecture. © 2015. Published by The Company of Biologists Ltd.

  11. Deep breathing heart rate variability is associated with respiratory muscle weakness in patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Michel Silva Reis

    2010-01-01

    Full Text Available BACKGROUND: A synchronism exists between the respiratory and cardiac cycles. However, the influence of the inspiratory muscle weakness in chronic obstructive pulmonary disease (COPD on cardiac autonomic control is unknown. The purpose of the present investigation was to evaluate the influence of respiratory muscle strength on autonomic control in these patients. METHODS: Ten chronic obstructive pulmonary disease patients (69±9 years; FEV1/FVC 59±12% and FEV1 41±11% predicted and nine age-matched healthy volunteers (64±5 years participated in this study. Heart-rate variability (HRV was obtained at rest and during respiratory sinusal arrhythmia maneuver (RSA-M by electrocardiograph. RESULTS: Chronic obstructive pulmonary disease patients demonstrated impaired cardiac autonomic modulation at rest and during RSA-M when compared with healthy subjects (p<0.05. Moreover, significant and positive correlations between maximal inspiratory pressure (MIP and the inspiratory-expiratory difference (ΔIE (r = 0.60, p<0.01 were found. CONCLUSION: Patients with chronic obstructive pulmonary disease presented impaired sympathetic-vagal balance at rest. In addition, cardiac autonomic control of heart rate was associated with inspiratory muscle weakness in chronic obstructive pulmonary disease. Based on this evidence, future research applications of respiratory muscle training may bring to light a potentially valuable target for rehabilitation.

  12. Concurrent Isolation of 3 Distinct Cardiac Stem Cell Populations From a Single Human Heart Biopsy.

    Science.gov (United States)

    Monsanto, Megan M; White, Kevin S; Kim, Taeyong; Wang, Bingyan J; Fisher, Kristina; Ilves, Kelli; Khalafalla, Farid G; Casillas, Alexandria; Broughton, Kathleen; Mohsin, Sadia; Dembitsky, Walter P; Sussman, Mark A

    2017-07-07

    The relative actions and synergism between distinct myocardial-derived stem cell populations remain obscure. Ongoing debates on optimal cell population(s) for treatment of heart failure prompted implementation of a protocol for isolation of multiple stem cell populations from a single myocardial tissue sample to develop new insights for achieving myocardial regeneration. Establish a robust cardiac stem cell isolation and culture protocol to consistently generate 3 distinct stem cell populations from a single human heart biopsy. Isolation of 3 endogenous cardiac stem cell populations was performed from human heart samples routinely discarded during implantation of a left ventricular assist device. Tissue explants were mechanically minced into 1 mm 3 pieces to minimize time exposure to collagenase digestion and preserve cell viability. Centrifugation removes large cardiomyocytes and tissue debris producing a single cell suspension that is sorted using magnetic-activated cell sorting technology. Initial sorting is based on tyrosine-protein kinase Kit (c-Kit) expression that enriches for 2 c-Kit + cell populations yielding a mixture of cardiac progenitor cells and endothelial progenitor cells. Flowthrough c-Kit - mesenchymal stem cells are positively selected by surface expression of markers CD90 and CD105. After 1 week of culture, the c-Kit + population is further enriched by selection for a CD133 + endothelial progenitor cell population. Persistence of respective cell surface markers in vitro is confirmed both by flow cytometry and immunocytochemistry. Three distinct cardiac cell populations with individualized phenotypic properties consistent with cardiac progenitor cells, endothelial progenitor cells, and mesenchymal stem cells can be successfully concurrently isolated and expanded from a single tissue sample derived from human heart failure patients. © 2017 American Heart Association, Inc.

  13. Sarcopenia in patients with heart failure with preserved ejection fraction: Impact on muscle strength, exercise capacity and quality of life.

    Science.gov (United States)

    Bekfani, Tarek; Pellicori, Pierpaolo; Morris, Daniel A; Ebner, Nicole; Valentova, Miroslava; Steinbeck, Lisa; Wachter, Rolf; Elsner, Sebastian; Sliziuk, Veronika; Schefold, Joerg C; Sandek, Anja; Doehner, Wolfram; Cleland, John G; Lainscak, Mitja; Anker, Stefan D; von Haehling, Stephan

    2016-11-01

    To describe the prevalence of sarcopenia in ambulatory patients with heart failure with preserved ejection fraction (HFpEF) and its relation to reduced exercise capacity, muscle strength, and quality of life (QoL). A total of 117 symptomatic outpatients with HFpEF were prospectively enrolled in Germany, England, and Slovenia as part of the Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF). Appendicular skeletal muscle (ASM) mass (the sum of muscle mass in both arms and legs) was assessed by DEXA. Echocardiography, 6-minute walk testing (6-MWT), muscle strength assessment, spiroergometry and QoL evaluation using EQ-5D Questionnaire were performed. Sarcopenia was defined as ASM 2 standard deviations below the mean of a healthy reference group aged 18-40years. Patients were divided into 3 groups according to the E/e' value: ≤8, 9-14, and ≥15. Sarcopenia was detected in 19.7% of all patients. These patients performed worse during 6-MWT (404±116 vs. 307±145m, p=0.003) and showed lower absolute peak oxygen consumption (1579±474 vs. 1211±442mL/min, p15 (p<0.05). Higher values of muscle strength/ASM were associated with a better QoL (r=0.5, p<0.0005). Logistic regression showed ASM to be independently associated with reduced distance walked during the 6-MWT adjusted for NYHA, height, left atrium diameter, ferritin and forced expiratory volume in 1s (FEV1) (odds ratio 1.2, p=0.02). Sarcopenia affects a clinically relevant proportion of patients with HFpEF. Low ASM is strongly linked to reduced muscle strength, exercise capacity and QoL in these patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. Role of fatty acid uptake and fatty acid beta-oxidation in mediating insulin resistance in heart and skeletal muscle.

    Science.gov (United States)

    Zhang, Liyan; Keung, Wendy; Samokhvalov, Victor; Wang, Wei; Lopaschuk, Gary D

    2010-01-01

    Fatty acids are a major fuel source used to sustain contractile function in heart and oxidative skeletal muscle. To meet the energy demands of these muscles, the uptake and beta-oxidation of fatty acids must be coordinately regulated in order to ensure an adequate, but not excessive, supply for mitochondrial beta-oxidation. However, imbalance between fatty acid uptake and beta-oxidation has the potential to contribute to muscle insulin resistance. The action of insulin is initiated by binding to its receptor and activation of the intrinsic protein tyrosine kinase activity of the receptor, resulting in the initiation of an intracellular signaling cascade that eventually leads to insulin-mediated alterations in a number of cellular processes, including an increase in glucose transport. Accumulation of fatty acids and lipid metabolites (such as long chain acyl CoA, diacylglycerol, triacylglycerol, and/or ceramide) can lead to alterations in this insulin signaling pathway. An imbalance between fatty acid uptake and oxidation is believed to be responsible for this lipid accumulation, and is thought to be a major cause of insulin resistance in obesity and diabetes, due to lipid accumulation and inhibition of one or more steps in the insulin-signaling cascade. As a result, decreasing muscle fatty acid uptake can improve insulin sensitivity. However, the potential role of increasing fatty acid beta-oxidation in the heart or skeletal muscle in order to prevent cytoplasmic lipid accumulation and decrease insulin resistance is controversial. While increased fatty acid beta-oxidation may lower cytoplasmic lipid accumulation, increasing fatty acid beta-oxidation can decrease muscle glucose metabolism, and incomplete fatty acid oxidation has the potential to also contribute to insulin resistance. In this review, we discuss the proposed mechanisms by which alterations in fatty acid uptake and oxidation contribute to insulin resistance, and how targeting fatty acid uptake and

  15. Inspiratory muscle training reduces sympathetic nervous activity and improves inspiratory muscle weakness and quality of life in patients with chronic heart failure: a clinical trial.

    Science.gov (United States)

    Mello, Priscila R; Guerra, Grazi M; Borile, Suellen; Rondon, Maria U; Alves, Maria J; Negrão, Carlos E; Dal Lago, Pedro; Mostarda, Cristiano; Irigoyen, Maria C; Consolim-Colombo, Fernanda M

    2012-01-01

    To evaluate the effect of inspiratory muscle training (IMT) on cardiac autonomic modulation and on peripheral nerve sympathetic activity in patients with chronic heart failure (CHF). Functional capacity, low-frequency (LF) and high-frequency (HF) components of heart rate variability, muscle sympathetic nerve activity inferred by microneurography, and quality of life were determined in 27 patients with CHF who had been sequentially allocated to 1 of 2 groups: (1) control group (with no intervention) and (2) IMT group. Inspiratory muscle training consisted of respiratory exercises, with inspiratory threshold loading of seven 30-minute sessions per week for a period of 12 weeks, with a monthly increase of 30% in maximal inspiratory pressure (PI(max)) at rest. Multivariate analysis was applied to detect differences between baseline and followup period. Inspiratory muscle training significantly increased PI(max) (59.2 ± 4.9 vs 87.5 ± 6.5 cmH(2)O, P = .001) and peak oxygen uptake (14.4 ± 0.7 vs 18.9 ± 0.8 mL·kg(-1)·min(-1), P = .002); decreased the peak ventilation (VE)/carbon dioxide production (VCO(2)) ratio (35.8 ± 0.8 vs 32.5 ± 0.4, P = .001) and the VE/VCO(2) slope (37.3 ± 1.1 vs 31.3 ± 1.1, P = .004); increased the HF component (49.3 ± 4.1 vs 58.4 ± 4.2 normalized units, P = .004) and decreased the LF component (50.7 ± 4.1 vs 41.6 ± 4.2 normalized units, P = .001) of heart rate variability; decreased muscle sympathetic nerve activity (37.1 ± 3 vs 29.5 ± 2.3 bursts per minute, P = .001); and improved quality of life. No significant changes were observed in the control group. Home-based IMT represents an important strategy to improve cardiac and peripheral autonomic controls, functional capacity, and quality of life in patients with CHF.

  16. Cardiac rehabilitation in a pediatric patient with heart retransplantation. A single case study.

    Science.gov (United States)

    Chang, K-V; Chiu, H-H; Wang, S-S; Lan, C; Chen, S-Y; Chou, N-K; Wu, M-H; Lai, J-S

    2014-04-01

    Cardiac rehabilitation (CR) after heart transplantation is known to benefit physical capacity in adults, but the advantages of CR on pediatric patients with heart retransplantation remain undetermined. The purpose of the present study was to report the effect of structured CR for a boy receiving heart transplantations twice. Single case study. Inpatient and outpatient rehabilitation department. A pediatric patient underwent heart transplantation due to dilated cardiomyopathy at 13.6 year-old and retransplantation owing to severe cardiac allograft vasculopathy at 16.2 year-old. CR was arranged after both transplantations. Bicycle or treadmill exercises were conducted three times weekly with the intensity adjusted to the ventilatory threshold. Serial cardiopulmonary exercise tests were performed to evaluate the sequential cardiorespiratory function changes using the peak oxygen uptake (VO₂peak) as the primary outcome. The patient had undergone 10 times of exercise tests during rehabilitation. The VO₂peak increased from 12.27 to 15.63 mL·kg-1·min-1 within 6 months after the primary transplantation. However, the VO₂peak dropped intensively after a rejection episode and failed to improve since the development of cardiac allograft vasculopathy. Following retransplantation, the VO₂peak appeared worse initially but increased gradually with rehabilitation. One year subsequent to retransplantation, the VO₂peak reached 17.7 mL·kg-1·min-1 with a 7.22 mL·kg-1·min-1 improvement compared with his baseline value. Structured CR improves aerobic capacity of a pediatric patient with heart retransplantation. CR is safe and beneficial for pediatrics with heart retransplantation. Cardiopulmonary exercise testing can be considered as an adjuvant tool for detecting rejection or cardiac allograft vasculopathy in pediatric heart transplantation recipients.

  17. What Is a Heart Attack?

    Science.gov (United States)

    ... to help prevent your first heart attack. Heart-Healthy Lifestyle Changes A heart-healthy lifestyle can help prevent ... blood to flow to the heart muscle. Heart-Healthy Lifestyle Changes Treatment for a heart attack usually includes ...

  18. Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

    International Nuclear Information System (INIS)

    Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

    2009-01-01

    Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

  19. A practical approach to assess leg muscle oxygenation during ramp-incremental cycle ergometry in heart failure

    Directory of Open Access Journals (Sweden)

    A.C. Barroco

    2017-10-01

    Full Text Available Heart failure is characterized by the inability of the cardiovascular system to maintain oxygen (O2 delivery (i.e., muscle blood flow in non-hypoxemic patients to meet O2 demands. The resulting increase in fractional O2 extraction can be non-invasively tracked by deoxygenated hemoglobin concentration (deoxi-Hb as measured by near-infrared spectroscopy (NIRS. We aimed to establish a simplified approach to extract deoxi-Hb-based indices of impaired muscle O2 delivery during rapidly-incrementing exercise in heart failure. We continuously probed the right vastus lateralis muscle with continuous-wave NIRS during a ramp-incremental cardiopulmonary exercise test in 10 patients (left ventricular ejection fraction <35% and 10 age-matched healthy males. Deoxi-Hb is reported as % of total response (onset to peak exercise in relation to work rate. Patients showed lower maximum exercise capacity and O2 uptake-work rate than controls (P<0.05. The deoxi-Hb response profile as a function of work rate was S-shaped in all subjects, i.e., it presented three distinct phases. Increased muscle deoxygenation in patients compared to controls was demonstrated by: i a steeper mid-exercise deoxi-Hb-work rate slope (2.2±1.3 vs 1.0±0.3% peak/W, respectively; P<0.05, and ii late-exercise increase in deoxi-Hb, which contrasted with stable or decreasing deoxi-Hb in all controls. Steeper deoxi-Hb-work rate slope was associated with lower peak work rate in patients (r=–0.73; P=0.01. This simplified approach to deoxi-Hb interpretation might prove useful in clinical settings to quantify impairments in O2 delivery by NIRS during ramp-incremental exercise in individual heart failure patients.

  20. The Comparing the Leg Muscles Electromyography during Single Leg Drop Landing in Pesplanus and Normal Men

    Directory of Open Access Journals (Sweden)

    mostafa bazvand

    2016-03-01

    Full Text Available Objective: pesplanus is one of the changes that brings about changes in muscle activation patterns. Being aware of muscles activity changes in various standing positions among pesplanus patients provides insights into preventing lower extremity injuries in this population. The aim of this study was to compare leg muscles electromyography during various standing positions in pesplanus and normal subjects. Methods: 60 healthy male university students, 30 subjects with pesplanus deformity (with average age 23/54±3/57 year, average height 175/34±7/62 cm, average weight 74/87±10/72 kg and 30 normal subjects (with average age 22/97±2/38 year, average height 176/6±5/59 cm, average weight 73/58±8/36 kg participated in this comparative study. Deformity of pesplanus was assessed with navicular drop test. Each subject performed single-leg landing dropping from 30cm height onto a force platform where muscles activity was recorded with EMG device. For data analysis, Matlab and Spss softwares were used and independent sample t-test was used to compare the dependent variables at a significance level of P &le 0/05. Results: Significant differences were observed between the two groups for the activities of the longus peroneus and anterior tibialis muscles ( p&le0/05 while no significant differences were observed in other muscles. Conclusion: The changes in the normal structure of the foot might affect muscle activities during standing, which can cause changes in the injury patterns. Therefore, it is proposed that focusing on corrective exercises and therapy plan can reduce these risks.

  1. [AO distribution and fluorescence spectra in myoblasts and single muscle fibres].

    Science.gov (United States)

    Beliaeva, T N; Krolenko, S A; Leont'eva, E A; Mozhenok, T P; Salova, A V; Faddeeva, M D

    2009-01-01

    Using spectral scanning regime of Leica TCS SL confocal microscope, acridine orange (AO) fluorescence spectra in nuclei and cytoplasms of living myoblasts L6J1 and frog single muscle fibres have been studied. AO fluorescence spectra in salt solutions dependent on free AO concentrations and in AO complexes with DNA have also been obtained for comparison. Myoblasts nuclei fluoresced in green spectral region with maximum at approximately 530 nm (corresponding AO monomers fluorescence), nucleoli fluoresced most brightly. Nuclear chromatin fluoresced not uniformly in these cells. We saw similar to myoblasts AO emission in nucleoli and nuclei of frog single muscle fibres. The uniformed weak green fluorescence was observed for myoblast cytoplasm. As to the muscle fibres sarcoplasm, we saw also AO green fluorescence in A-discs. In myoblasts and muscle fibre cytoplasm we saw the fluorescent red, yellow and green granules which were acidic organelles. The comparison of AO fluorescence spectra in living cells with fluorescence spectra of different AO concentrations and complexes of AO with DNA in buffer solutions allows estimation of AO concentration in acidic granules which is of interest in the investigation of cellular organelles functions in the processes of intracellular transport, adaptation, apoptosis and a number of pathological conditions.

  2. Evaluation of Skeletal Muscle Function and Effects of Early Rehabilitation during Acute Heart Failure: Rationale and Study Design

    Directory of Open Access Journals (Sweden)

    Kinga Węgrzynowska-Teodorczyk

    2018-01-01

    Full Text Available Background. Acute heart failure (AHF is associated with disturbances of the peripheral perfusion leading to the dysfunction of many organs. Consequently, an episode of AHF constitutes a “multiple organ failure” which may also affect the skeletal muscles. However, the abnormalities within skeletal muscles during AHF have not been investigated so far. The aim of this project is to comprehensively evaluate skeletal muscles (at a functional and tissue level during AHF. Methods. The study will include ≥63 consecutive AHF patients who will be randomized into 2 groups: ≥42 with cardiac rehabilitation group versus ≥21 with standard pharmacotherapy alone. The following tests will be conducted on the first and last day of hospitalization, at rest and after exercise, and 30 days following the discharge: clinical evaluation, medical interview, routine physical examination, echocardiography, and laboratory tests (including the assessment of NT-proBNP, inflammatory markers, and parameters reflecting the status of the kidneys and the liver; hemodynamic evaluation, noninvasive determination of cardiac output and systemic vascular resistance using the impedance cardiography; evaluation of biomarkers reflecting myocyte damage, immunochemical measurements of tissue-specific enzymatic isoforms; evaluation of skeletal muscle function, using surface electromyography (sEMG (maximum tonus of the muscles will be determined along with the level of muscular fatigability; evaluation of muscle tissue perfusion, assessed on the basis of the oxygenation level, with noninvasive direct continuous recording of perfusion in peripheral tissues by local tissue oximetry, measured by near-infrared spectroscopy (NIRS. Results and Conclusions. Our findings will demonstrate that the muscle tissue is another area of the body which should be taken into consideration in the course of treatment of AHF, requiring a development of targeted therapeutic strategies, such as a properly

  3. Cloning and tissue distribution of rat hear fatty acid binding protein mRNA: identical forms in heart and skeletal muscle

    International Nuclear Information System (INIS)

    Claffey, K.P.; Herrera, V.L.; Brecher, P.; Ruiz-Opazo, N.

    1987-01-01

    A fatty acid binding protein (FABP) as been identified and characterized in rat heart, but the function and regulation of this protein are unclear. In this study the cDNA for rat heart FABP was cloned from a λ gt11 library. Sequencing of the cDNA showed an open reading frame coding for a protein with 133 amino acids and a calculated size of 14,776 daltons. Several differences were found between the sequence determined from the cDNA and that reported previously by protein sequencing techniques. Northern blot analysis using rat heart FABP cDNA as a probe established the presence of an abundant mRNA in rat heart about 0.85 kilobases in length. This mRNA was detected, but was not abundant, in fetal heart tissue. Tissue distribution studies showed a similar mRNA species in red, but not white, skeletal muscle. In general, the mRNA tissue distribution was similar to that of the protein detected by Western immunoblot analysis, suggesting that heart FABP expression may be regulated at the transcriptional level. S1 nuclease mapping studies confirmed that the mRNA hybridized to rat heart FABP cDNA was identical in heart and red skeletal muscle throughout the entire open reading frame. The structural differences between heart FABP and other members of this multigene family may be related to the functional requirements of oxidative muscle for fatty acids as a fuel source

  4. Cloning and tissue distribution of rat hear fatty acid binding protein mRNA: identical forms in heart and skeletal muscle

    Energy Technology Data Exchange (ETDEWEB)

    Claffey, K.P.; Herrera, V.L.; Brecher, P.; Ruiz-Opazo, N.

    1987-12-01

    A fatty acid binding protein (FABP) as been identified and characterized in rat heart, but the function and regulation of this protein are unclear. In this study the cDNA for rat heart FABP was cloned from a lambda gt11 library. Sequencing of the cDNA showed an open reading frame coding for a protein with 133 amino acids and a calculated size of 14,776 daltons. Several differences were found between the sequence determined from the cDNA and that reported previously by protein sequencing techniques. Northern blot analysis using rat heart FABP cDNA as a probe established the presence of an abundant mRNA in rat heart about 0.85 kilobases in length. This mRNA was detected, but was not abundant, in fetal heart tissue. Tissue distribution studies showed a similar mRNA species in red, but not white, skeletal muscle. In general, the mRNA tissue distribution was similar to that of the protein detected by Western immunoblot analysis, suggesting that heart FABP expression may be regulated at the transcriptional level. S1 nuclease mapping studies confirmed that the mRNA hybridized to rat heart FABP cDNA was identical in heart and red skeletal muscle throughout the entire open reading frame. The structural differences between heart FABP and other members of this multigene family may be related to the functional requirements of oxidative muscle for fatty acids as a fuel source.

  5. Single sodium channels from human skeletal muscle in planar lipid bilayers: characterization and response to pentobarbital.

    Science.gov (United States)

    Wartenberg, Hans C; Urban, Bernd W

    2004-01-01

    To investigate the response to general anesthetics of different sodium-channel subtypes, we examined the effects of pentobarbital, a close thiopental analogue, on single sodium channels from human skeletal muscle and compared them to existing data from human brain and human ventricular muscle channels. Sodium channels from a preparation of human skeletal muscle were incorporated into planar lipid bilayers, and the steady-state behavior of single sodium channels and their response to pentobarbital was examined in the presence of batrachotoxin, a sodium-channel activator. Single-channel currents were recorded before and after the addition of pentobarbital (0.34-1.34 mM). In symmetrical 500 mM NaCl, human skeletal muscle sodium channels had an averaged single-channel conductance of 21.0 +/- 0.6 pS, and the channel fractional open time was 0.96 +/- 0.04. The activation midpoint potential was -96.2 +/- 1.6 mV. Extracellular tetrodotoxin blocked the channel with a half-maximal concentration (k1/2) of 60 nM at 0 mV. Pentobarbital reduced the time-averaged conductance of single skeletal muscle sodium channels in a concentration-dependent manner (inhibitory concentration 50% [IC50] = 0.66 mM). The steady-state activation was shifted to more hyperpolarized potentials (-16.7 mV at 0.67 mM pentobarbital). In the planar lipid bilayer system, skeletal muscle sodium channels have some electrophysiological properties that are significantly different compared with those of sodium channels from cardiac or from central nervous tissue. In contrast to the control data, these different human sodium channel subtypes showed the same qualitative and quantitative response to the general anesthetic pentobarbital. The implication of these effects for overall anesthesia will depend on the role the individual channels play within their neuronal networks, but suppression of both central nervous system and peripheral sodium channels may add to general anesthetic effects.

  6. Heart and skeletal muscle inflammation (HSMI disease diagnosed on a British Columbia salmon farm through a longitudinal farm study.

    Directory of Open Access Journals (Sweden)

    Emiliano Di Cicco

    Full Text Available Heart and skeletal muscle inflammation (HSMI is an emerging disease of marine-farmed Atlantic Salmon (Salmo salar, first recognized in 1999 in Norway, and later also reported in Scotland and Chile. We undertook a longitudinal study involving health evaluation over an entire marine production cycle on one salmon farm in British Columbia (Canada. In previous production cycles at this farm site and others in the vicinity, cardiac lesions not linked to a specific infectious agent or disease were identified. Histologic assessments of both live and moribund fish samples collected at the farm during the longitudinal study documented at the population level the development, peak, and recovery phases of HSMI. The fish underwent histopathological evaluation of all tissues, Twort's Gram staining, immunohistochemistry, and molecular quantification in heart tissue of 44 agents known or suspected to cause disease in salmon. Our analysis showed evidence of HSMI histopathological lesions over an 11-month timespan, with the prevalence of lesions peaking at 80-100% in sampled fish, despite mild clinical signs with no associated elevation in mortalities reported at the farm level. Diffuse mononuclear inflammation and myodegeneration, consistent with HSMI, was the predominant histologic observation in affected heart and skeletal muscle. Infective agent monitoring identified three agents at high prevalence in salmon heart tissue, including Piscine orthoreovirus (PRV, and parasites Paranucleospora theridion and Kudoa thyrsites. However, PRV alone was statistically correlated with the occurrence and severity of histopathological lesions in the heart. Immunohistochemical staining further localized PRV throughout HSMI development, with the virus found mainly within red blood cells in early cases, moving into the cardiomyocytes within or, more often, on the periphery of the inflammatory reaction during the peak disease, and reducing to low or undetectable levels later in

  7. Changes in satellite cells in human skeletal muscle after a single bout of high intensity exercise

    DEFF Research Database (Denmark)

    Crameri, Regina M; Langberg, Henning; Magnusson, Peter

    2004-01-01

    No studies to date have reported activation of satellite cells in vivo in human muscle after a single bout of high intensity exercise. In this investigation, eight individuals performed a single bout of high intensity exercise with one leg, the contralateral leg being the control. A significant...... increase in mononuclear cells staining for the neural cell adhesion molecule (N-CAM) and fetal antigen 1 (FA1) were observed within the exercised human vastus lateralis muscle on days 4 and 8 post exercise. In addition, a significant increase in the concentration of the FA1 protein was determined...... in the control leg. Despite this increase in N-CAM- and FA1-positive mononuclear cells, an increased expression of myogenin and the neonatal isoform of the myosin heavy chain (MHCn) was not observed. Interestingly, myofibre lesions resulting from extensive damage to the proteins within the myofibre, particularly...

  8. Enhanced procollagen processing in skeletal muscle after a single bout of eccentric loading in humans

    DEFF Research Database (Denmark)

    Crameri, Regina M; Langberg, Henning; Teisner, Børge

    2004-01-01

    young healthy male subjects performed a single bout of unaccustomed high intensity eccentric exercise on one leg, with the contralateral leg being the control. A significant increase in the muscle interstitial concentration of the N-terminal propeptide of procollagen type I (PINP) was observed (day 0: 1......-terminal propeptide of procollagen type III (PIIINP) was also shown in the exercising leg only. Further, from day 2 post-exercise, immunoreactivity for tenascin C and reactive macrophages (CD68+ cells) was seen within the perimysial and endomysial connective tissue of the exercising leg only, indicating a high...... mechanical load and inflammation. This study shows that following a single bout of high intensity eccentric exercise there is an increase in procollagen processing within skeletal muscle in humans....

  9. Efficacy of inspiratory muscle training in chronic heart failure patients: a systematic review and meta-analysis.

    Science.gov (United States)

    Smart, Neil A; Giallauria, Francesco; Dieberg, Gudrun

    2013-08-20

    Inspiratory muscle training (IMT) offers an alternative to exercise training (ExT) in the most severely deconditioned heart failure patients who are unable to exercise. We conducted a meta-analysis to determine magnitude of change in peak VO2, six minute walk distance (6MWD), Quality of Life measured by the Minnesota Living with Heart Failure Questionnaire (MLWHFQ), maximal inspiratory pressure (PI max) and ventilatory equivalent for carbon dioxide (VE/VCO2 slope) with IMT. A systematic search was conducted of randomized, controlled trials of IMT therapy in CHF patients using Medline (Ovid) (1950-February 2012), Embase.com (1974-February 2012), Cochrane Central Register of Controlled Trials and CINAHL (1981-February 2012). The search strategy included a mix of MeSH and free text terms for the key concepts heart failure, inspiratory or respiratory muscle training, exercise training The eleven included studies contained data on 287 participants: 148 IMT participants and 139 sham or sedentary control. Compared to control groups, CHF patients undergoing IMT showed a significant improvement in peak VO2 (+1.83 ml kg(-1) min(-1), 95% C.I. 1.33 to 2.32 ml kg(-1) min(-1), ptraining and may provide an initial alternative to the more severely de-conditioned CHF patients who may then transition to conventional ExT. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Megaconial muscular dystrophy caused by mitochondrial membrane homeostasis defect, new insights from skeletal and heart muscle analyses.

    Science.gov (United States)

    Vanlander, Arnaud V; Muiño Mosquera, Laura; Panzer, Joseph; Deconinck, Tine; Smet, Joél; Seneca, Sara; Van Dorpe, Jo; Ferdinande, Liesbeth; Ceuterick-de Groote, Chantal; De Jonghe, Peter; Van Coster, Rudy; Baets, Jonathan

    2016-03-01

    Megaconial congenital muscular dystrophy is a disease caused by pathogenic mutations in the gene encoding choline kinase beta (CHKB). Microscopically, the disease is hallmarked by the presence of enlarged mitochondria at the periphery of skeletal muscle fibres leaving the centre devoid of mitochondria. Clinical characteristics are delayed motor development, intellectual disability and dilated cardiomyopathy in half of reported cases. This study describes a patient presenting with the cardinal clinical features, in whom a homozygous nonsense mutation (c.248_249insT; p.Arg84Profs*209) was identified in CHKB and who was treated by heart transplantation. Microscopic evaluation of skeletal and heart muscles typically showed enlarged mitochondria. Spectrophotometric evaluation in both tissues revealed a mild decrease of all OXPHOS complexes. Using BN-PAGE analysis followed by activity staining subcomplexes of complex V were detected in both tissues, indicating incomplete complex V assembly. Mitochondrial DNA content was not depleted in analysed tissues. This is the first report describing the microscopic and biochemical abnormalities in the heart from an affected patient. A likely hypothesis is that the biochemical findings are caused by an abnormal lipid profile in the inner mitochondrial membrane resulting from a defective choline kinase B activity. Copyright © 2016 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  11. Improvement in hamstring and quadriceps muscle strength following cruciate-retaining single radius total knee arthroplasty.

    Science.gov (United States)

    Kurowicki, Jennifer; Khlopas, Anton; Sultan, Assem A; Sodhi, Nipun; Samuel, Linsen T; Chughtai, Morad; Roche, Martin; Bonutti, Peter M; Mont, Michael A

    2017-12-01

    The ability to reach full functional capacity following total knee arthroplasty (TKA) is reliant on the strength of the quadriceps and hamstring muscles. Weakness of these muscles can persist anywhere from 1 to 3 years post-operatively. There remains considerable controversy as to what factors influence restoration of muscle strength after TKA. Implant designs have been implicated in the ability of patients to recover. Currently there is a paucity of literature available describing the influence of patient characteristics, surgical factors, and clinical outcomes on quadriceps and hamstring muscle strength following TKA with a cruciate-retaining, single radius (SR) implant. For this reason, we sought to investigate TKA patients for: (I) quadriceps muscle strength; (II) hamstring muscle strength; (III) flexion/extension (F/E) ratio; (IV) clinical outcome scores; (V) influence of patient characteristics on muscle strength at one-year post-operatively. A review of TKA patients who were assessed for hamstring and quadriceps muscle strength was conducted. A total of 39 patients (26 men and 13 women), who had a mean age of 68 years (range, 51 to 88 years) were included. Isokinetic dynamometer testing at 180 degree/second for 3 sets of 10 repetitions in extension and flexion were performed by an independent physical therapist to assess dynamic concentric torque of the hamstrings and quadriceps muscle. F/E ratios were calculated. TKA was performed via subvastus (n=20) or midvastus (n=19) approach. Subgroup analysis for surgical approach, concomitant spinal pathology (n=11), gender, age and body mass index (BMI) were performed. Knee Society Scores (KSS) and range of motion (ROM) were assessed at each visit. Comparisons of groups were performed using paired t -tests. Mean postoperative relative extension torque was 23 Nm/kg (range, 9 to 43 Nm/kg), representing a mean increase of 38% (range, -16% to 100%; P=0.0267) from pre-operative status. A mean increase of 27% (range, -15

  12. Heart failure from heart muscle disease in childhood: a 5-10 year follow-up study in the UK and Ireland.

    Science.gov (United States)

    Andrews, Rachel E; Fenton, Matthew J; Dominguez, Troy; Burch, Michael

    2016-06-01

    Our original study, the first national prospective study of new-onset heart failure from heart muscle disease in children, showed overall 1-year survival of 82%, and event (death or transplantation)-free survival of 66%. This study aimed to evaluate 5 + year outcomes of this important cohort. All centres in the UK and Ireland with 1-year event-free survivors participated ( n  = 14). Anonymised data based on last hospital attendance and echocardiograms were reviewed. The investigator was blinded to outcome at the time of echo review. Of sixty-nine 1-year event-free survivors, data were obtained on 64, with three lost to follow-up and two moved abroad. There were three deaths at 2.2, 3.3 and 9.0 years after presentation and one transplant, at 5.2 years. Overall/event-free survival was 77%/62% at 5 years and 73%/59% at 10 years, respectively. Overall and event-free survival conditional on 1-year survival was 94% at 5 years, and 89% at 10 years. For the 60 event-free survivors, median (range) follow-up duration was 9.04 (5.0-10.33) years for those still under review ( n  = 45), or time to discharge 5.25 (0.67-10.0) years ( n  = 15). Fifty-eight were in New York Heart Association (NYHA) Class 1, and two in Class 2. Forty-one out of sixty had normal echocardiograms at last follow-up. Predictors of better longer-term outcome were the same as for the original 1-year follow-up study, namely, younger age and higher fractional shortening measurement at presentation. Children who survive the first year following their first presentation with significant heart failure from heart muscle disease have a good longer-term outcome although there remains a small attrition rate.

  13. Ankle muscle activity modulation during single-leg stance differs between children, young adults and seniors.

    Science.gov (United States)

    Kurz, Eduard; Faude, Oliver; Roth, Ralf; Zahner, Lukas; Donath, Lars

    2018-02-01

    Incomplete maturation and aging-induced declines of the neuromuscular system affect postural control both in children and older adults and lead to high fall rates. Age-specific comparisons of the modulation of ankle muscle activation and behavioral center of pressure (COP) indices during upright stance have been rarely conducted. The objective of the present study was to quantify aging effects on a neuromuscular level. Thus, surface electromyography (SEMG) modulation and co-activity of ankle muscles during single-leg standing was compared in healthy children, young adults and seniors. Postural steadiness (velocity and mean sway frequency of COP), relative muscle activation (SEMG modulation) and co-activation of two ankle muscles (tibialis anterior, TA; soleus, SO) were examined during single-leg stance in 19 children [age, 9.7 (SD 0.5) years], 30 adults [23.3 (1.5) years] and 29 seniors [62.7 (6.1) years]. Velocity of COP in medio-lateral and anterior-posterior directions, mean sway frequency in anterior-posterior direction, relative muscle activation (TA and SO) and co-activation revealed large age effects (P  0.14). Post-hoc comparisons indicated higher COP velocities, anterior-posterior frequencies, relative SO activation and co-activation in children and seniors when compared with adults. Relative TA activation was higher in children and adults compared with seniors (P modulation. However, TA modulation is higher in children and adults, whereas seniors' TA modulation capacity is diminished. An aging-induced decline of TA motor units might account for deteriorations of TA modulation in seniors.

  14. Muscle free amino acid profiles are related to differences in skeletal muscle growth between single and twin ovine fetuses near term.

    Science.gov (United States)

    Sales, Francisco; Pacheco, David; Blair, Hugh; Kenyon, Paul; McCoard, Sue

    2013-01-01

    Twin sheep fetuses have reduced skeletal muscle weight near birth relative to singles as a result of restricted muscle hypertrophy. Intracellular free amino acids (FAA) are reported to regulate metabolic pathways which control muscle protein accretion, whereby reduced intracellular content of specific FAA may reduce their activation and therefore, muscle hypertrophy. The aim of this study was to determine whether differences in muscle weight between singleton and twin fetuses, under different maternal conditions is associated with reduced concentration of specific FAA. The FAA content in the semitendinosus muscle (ST) in singleton and twin fetuses (rank) at 140 days of gestation from heavy (H) or light (L) ewes fed ad libitum (A) or maintenance (M) level of nutrition was measured. Muscle weight was reduced in twin fetuses compared to singletons in all groups. Reduced concentrations of leucine, threonine and valine, but higher concentrations of methionine, ornithine, lysine and serine were found in twin fetuses compared to singletons. Maternal size and nutrition interaction with rank resulted in reduced glutamine in twins from HM-ewes (H-ewes under M nutrition) compared to their singleton counterparts. Maternal weight interaction with pregnancy rank reduced the concentration of arginine in twins, with a larger effect on H-ewes compared with L-ewes. Maternal size interaction with pregnancy rank resulted in twins from M-ewes to have lower alanine, while twins from A-ewes had lower aspartic acid concentration compared to singletons. The ST muscle weight was positively correlated only with arginine concentration after taking into account rank, size and nutrition. The present results indicate that reduced concentrations of specific intracellular FAA, such as arginine, leucine, valine, glutamine, which are known to play a role in muscle growth, could be acting as limiting factors for muscle hypertrophy in twin fetuses during late gestation. Ewe size and nutrition can

  15. Single vs. Multi-Joint Resistance Exercises: Effects on Muscle Strength and Hypertrophy

    Science.gov (United States)

    Gentil, Paulo; Soares, Saulo; Bottaro, Martim

    2015-01-01

    Background: Some authors suggest that single joint (SJ) exercises promote greater muscle hypertrophy because they are easier to be learned and therefore have less reliance on neural factors. On the other hand, some authors recommend an emphasis on multi-joint (MJ) exercises for maximizing muscle strength, assuming that MJ exercises are more effective than SJ exercises because they enable a greater magnitude of weight to be lifted. Objectives: The present study aimed to compare the effects of MJ vs. SJ exercises on muscle size and strength gains in untrained young men. Patients and Methods: Twenty-nine young men, without prior resistance training experience, were randomly divided into two groups. One group performed (n = 14) only MJ exercises involving the elbow flexors (lat. pull downs), while the other (n = 15) trained the elbow flexors muscles using only SJ exercises (biceps curls). Both groups trained twice a week for a period of ten weeks. The volunteers were evaluated for peak torque of elbow flexors (PT) in an isokinetic dynamometer and for muscle thickness (MT) by ultrasonography. Results: There were significant increases in MT of 6.10% and 5.83% for MJ and SJ, respectively; and there were also significant increases in PT for MJ (10.40%) and SJ (11.87%). However, the results showed no difference between groups pre or post training for MT or PT. Conclusions: In conclusion, the results of the present study suggest that MJ and SJ exercises are equally effective for promoting increases in upper body muscle strength and size in untrained men. Therefore, the selection between SJ and MJ exercises should be based on individual and practical aspects, such as, equipment availability, movement specificity, individual preferences and time commitment. PMID:26446291

  16. Characterization of the C-protein from posterior latissimus dorsi muscle of the adult chicken: heterogeneity within a single sarcomere

    OpenAIRE

    1983-01-01

    Specific isoforms of myofibrillar proteins are expressed in different muscles and in various fiber types within a single muscle. We have isolated and characterized monoclonal antibodies against C-proteins from slow tonic (anterior latissimus dorsi, ALD) and fast twitch (pectoralis major) muscles of the chicken. Although the antibody against "fast" C-protein (MF-1) did not bind to the "slow" isoform and the antibody to the "slow" C-protein (ALD-66) did not bind to the "fast" isoform, we observ...

  17. HeartMate II Left Ventricular Assist Device Pump Exchange: A Single-Institution Experience.

    Science.gov (United States)

    Shaikh, Asad F; Joseph, Susan M; Lima, Brian; Hall, Shelley A; Malyala, Rajasekhar; Rafael, Aldo E; Gonzalez-Stawinski, Gonzalo V; Chamogeorgakis, Themistokles

    2017-08-01

    Background  Left ventricular assist devices (LVADs) have revolutionized the treatment of patients with end-stage heart failure. These devices are replaced when pump complications arise if heart transplant is not possible. We present our experience with HeartMate II (HMII (Thoratec, Plesanton, California, United States)) LVAD pump exchange. Materials and Methods  We retrospectively reviewed all cases that required pump exchange due to LVAD complication from November 2011 until June 2016 at a single high-volume institution. The indications, demographics, and outcome were extracted and analyzed. Results  Of 250 total patients with implanted HMII LVADs, 16 (6%) required pump exchange during the study period. The initial indications for LVAD placement in these patients were bridge to transplantation ( n  = 6 [37.5%]) or destination therapy ( n  = 10 [62.5%]). Fifteen patients (93.8%) required pump exchange due to pump thrombosis and 1 (6.2%) due to refractory driveline infection. Nine patients (56.2%) underwent repeat median sternotomy while a left subcostal approach was used in the remaining seven patients. Fifteen patients (93.7%) survived until hospital discharge. During the follow-up period (median, 155 days), 11 patients remained alive and 4 of these underwent successful cardiac transplantation. Conclusion  HMII LVAD pump exchange can be safely performed for driveline infection or pump thrombosis when heart transplantation is not an option. Georg Thieme Verlag KG Stuttgart · New York.

  18. Improved Ventilatory Efficiency with Locomotor Muscle Afferent Inhibition is Strongly Associated with Leg Composition in Heart Failure.

    Science.gov (United States)

    Keller-Ross, Manda L; Johnson, Bruce D; Carter, Rickey E; Joyner, Michael J; Eisenach, John H; Curry, Timothy B; Olson, Thomas P

    2016-01-01

    Skeletal muscle atrophy contributes to increased afferent feedback (group III and IV) and may influence ventilatory control (high VE/VCO2 slope) in heart failure (HF). This study examined the influence of muscle mass on the change in VE/VCO2 with afferent neural block during exercise in HF. 17 participants [9 HF (60±6 yrs) and 8 controls (CTL) (63±7 yrs, mean±SD)] completed 3 sessions. Session 1: dual energy x-ray absorptiometry and graded cycle exercise to volitional fatigue. Sessions 2 and 3: 5 min of constant-work cycle exercise (65% of peak power) randomized to lumbar intrathecal injection of fentanyl (afferent blockade) or placebo. Ventilation (VE) and gas exchange (oxygen consumption, VO2; carbon dioxide production, VCO2) were measured. Peak work and VO2 were lower in HF (pLeg fat was greater in HF (34.4±3.0 and 26.3±1.8%) and leg muscle mass was lower in HF (63.0±2.8 and 70.4±1.8%, respectively, pleg muscle mass (r2=0.58, pleg fat mass (r2=0.73, pleg muscle mass had the greatest improvement in VE/VCO2 with afferent blockade with leg fat mass being the only predictor for the improvement in VE/VCO2 slope. Both leg muscle mass and fat mass are important contributors to ventilatory abnormalities and strongly associated to improvements in VE/VCO2 slope with locomotor afferent inhibition in HF. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Bradykinin Contributes to Sympathetic and Pressor Responses Evoked by Activation of Skeletal Muscle Afferents P2X in Heart Failure

    Directory of Open Access Journals (Sweden)

    Jihong Xing

    2016-11-01

    Full Text Available Background/Aims: Published data suggest that purinergic P2X receptors of muscle afferent nerves contribute to the enhanced sympathetic nervous activity (SNA and blood pressure (BP responses during static exercise in heart failure (HF. In this study, we examined engagement of bradykinin (BK in regulating responses of SNA and BP evoked by P2X stimulation in rats with HF. We further examined cellular mechanisms responsible for BK. We hypothesized that BK potentiates P2X currents of muscle dorsal root ganglion (DRG neurons, and this effect is greater in HF due to upregulation of BK kinin B2 and P2X3 receptor. As a result, BK amplifies muscle afferents P2X-mediated SNA and BP responses. Methods: Renal SNA and BP responses were recorded in control rats and rats with HF. Western Blot analysis and patch-clamp methods were employed to examine the receptor expression and function of DRG neurons involved in the effects of BK. Results: BK injected into the arterial blood supply of the hindlimb muscles heightened the reflex SNA and BP responses induced by P2X activation with α,β-methylene ATP to a greater degree in HF rats. In addition, HF upregulated the protein expression of kinin B2 and P2X3 in DRG and the prior application of BK increased the magnitude of α,β-methylene ATP-induced currents in muscle DRG neurons from HF rats. Conclusion: BK plays a facilitating role in modulating muscle afferent P2X-engaged reflex sympathetic and pressor responses. In HF, P2X responsivness is augmented due to increases in expression of kinin B2 and P2X3 receptors and P2X current activity.

  20. Sleep-Disordered Breathing Exacerbates Muscle Vasoconstriction and Sympathetic Neural Activation in Patients with Systolic Heart Failure.

    Science.gov (United States)

    Lobo, Denise M L; Trevizan, Patricia F; Toschi-Dias, Edgar; Oliveira, Patricia A; Piveta, Rafael B; Almeida, Dirceu R; Mady, Charles; Bocchi, Edimar A; Lorenzi-Filho, Geraldo; Middlekauff, Holly R; Negrão, Carlos E

    2016-11-01

    Sleep-disordered breathing (SDB) is common in patients with heart failure (HF), and hypoxia and hypercapnia episodes activate chemoreceptors stimulating autonomic reflex responses. We tested the hypothesis that muscle vasoconstriction and muscle sympathetic nerve activity (MSNA) in response to hypoxia and hypercapnia would be more pronounced in patients with HF and SDB than in patients with HF without SDB (NoSBD). Ninety consecutive patients with HF, New York Heart Association functional class II-III, and left ventricular ejection fraction ≤40% were screened for the study. Forty-one patients were enrolled: NoSDB (n=13, 46 [39-53] years) and SDB (n=28, 57 [54-61] years). SDB was characterized by apnea-hypopnea index ≥15 events per hour (polysomnography). Peripheral (10% O 2 and 90% N 2 , with CO 2 titrated) and central (7% CO 2 and 93% O 2 ) chemoreceptors were stimulated for 3 minutes. Forearm and calf blood flow were evaluated by venous occlusion plethysmography, MSNA by microneurography, and blood pressure by beat-to-beat noninvasive technique. Baseline forearm blood flow, forearm vascular conductance, calf blood flow, and calf vascular conductance were similar between groups. MSNA was higher in the SDB group. During hypoxia, the vascular responses (forearm blood flow, forearm vascular conductance, calf blood flow, and calf vascular conductance) were significantly lower in the SDB group compared with the NoSDB group (Phypoxia (P=0.024) and tended to be higher to hypercapnia (P=0.066) in the SDB group. Patients with HF and SDB have more severe muscle vasoconstriction during hypoxia and hypercapnia than HF patients without SDB, which seems to be associated with endothelial dysfunction and, in part, increased MSNA response. © 2016 American Heart Association, Inc.

  1. Heart rate detection from single-foot plantar bioimpedance measurements in a weighing scale.

    Science.gov (United States)

    Diaz, Delia H; Casas, Oscar; Pallas-Areny, Ramon

    2010-01-01

    Electronic bathroom scales are an easy-to-use, affordable mean to measure physiological parameters in addition to body weight. They have been proposed to obtain the ballistocardiogram (BCG) and derive from it the heart rate, cardiac output and systolic blood pressure. Therefore, weighing scales may suit intermittent monitoring in e-health and patient screening. Scales intended for bioelectrical impedance analysis (BIA) have also been proposed to estimate the heart rate by amplifying the pulsatile impedance component superimposed on the basal impedance. However, electronic weighing scales cannot easily obtain the BCG from people that have a single leg neither are bioimpedance measurements between both feet recommended for people wearing a pacemaker or other electronic implants, neither for pregnant women. We propose a method to detect the heart rate (HR) from bioimpedance measured in a single foot while standing on an bathroom weighting scale intended for BIA. The electrodes built in the weighing scale are used to apply a 50 kHz voltage between the outer electrode pair and to measure the drop in voltage across the inner electrode pair. The agreement with the HR simultaneously obtained from the ECG is excellent. We have also compared the drop in voltage across the waist and the thorax with that obtained when measuring bioimpedance between both feet to compare the possible risk of the proposed method to that of existing BIA scales.

  2. Expression of TPM1κ, a Novel Sarcomeric Isoform of the TPM1 Gene, in Mouse Heart and Skeletal Muscle

    OpenAIRE

    Dube, Syamalima; Panebianco, Lauren; Matoq, Amr A.; Chionuma, Henry N.; Denz, Christopher R.; Poiesz, Bernard J.; Dube, Dipak K.

    2014-01-01

    We have investigated the expression of TPM1 α and TPM1 κ in mouse striated muscles. TPM1 α and TMP1 κ were amplified from the cDNA of mouse heart by using conventional RT-PCR. We have cloned the PCR amplified DNA and determined the nucleotide sequences. Deduced amino acid sequences show that there are three amino acid changes in mouse exon 2a when compared with the human TPM1 κ . However, the deduced amino acid sequences of human TPM1 α and mouse TPM1 α are identical. Conventional RT-PCR data...

  3. Aerobic training and l-arginine supplementation promotes rat heart and hindleg muscles arteriogenesis after myocardial infarction.

    Science.gov (United States)

    Ranjbar, Kamal; Rahmani-Nia, Farhad; Shahabpour, Elham

    2016-09-01

    Arteriogenesis is a main defense mechanism to prevent heart and local tissues dysfunction in occlusive artery disease. TGF-β and angiostatin have a pivotal role in arteriogenesis. We tested the hypothesis that aerobic training and l-arginine supplementation promotes cardiac and skeletal muscles arteriogenesis after myocardial infarction (MI) parallel to upregulation of TGF-β and downregulation of angiostatin. For this purpose, 4 weeks after LAD occlusion, 50 male Wistar rats were randomly distributed into five groups: (1) sham surgery without MI (sham, n = 10), (2) control-MI (Con-MI, n = 10), (3) l-arginine-MI (La-MI, n = 10), (4) exercise training-MI (Ex-MI, n = 10), and (5) exercise and l-arginine-MI (Ex + La-MI). Exercise training groups running on a treadmill for 10 weeks with moderate intensity. Rats in the l-arginine-treated groups drank water containing 4 % l-arginine. Arteriolar density with different diameters (11-25, 26-50, 51-75, and 76-150 μm), TGF-β, and angiostatin gene expression were measured in cardiac (area at risk) and skeletal (soleus and gastrocnemius) muscles. Smaller arterioles decreased in cardiac after MI. Aerobic training and l-arginine increased the number of cardiac arterioles with 11-25 and 26-50 μm diameters parallel to TGF-β overexpression. In gastrocnemius muscle, the number of arterioles/mm(2) was only increased in the 11 to 25 μm in response to training with and without l-arginine parallel to angiostatin downregulation. Soleus arteriolar density with different size was not different between experimental groups. Results showed that 10 weeks aerobic exercise training and l-arginine supplementation promotes arteriogenesis of heart and gastrocnemius muscles parallel to overexpression of TGF-β and downregulation of angiostatin in MI rats.

  4. The effect of double versus single oscillating exercise devices on trunk and limb muscle activation.

    Science.gov (United States)

    Arora, Shruti; Button, Duane C; Basset, Fabien A; Behm, David G

    2013-08-01

    Proper strengthening of the core and upper extremities is important for muscular health, performance, and rehabilitation. Exercise devices have been developed that attempt to disrupt the center of gravity in order to activate the trunk stabilizing muscles. The objective of this study was to analyze the trunk and shoulder girdle muscle activation with double and single oscillating exercise devices (DOD and SOD respectively) in various planes. TWELVE MALE SUBJECTS PERFORMED THREE INTERVENTIONS USING BOTH DEVICES UNDER RANDOMIZED CONDITIONS: single-handed vertical orientation of DOD and SOD to produce 1) medio-lateral oscillation in the frontal plane 2) dorso-ventral oscillation in the sagittal plane and 3) single-handed horizontal orientation for superior and inferior oscillation in the transverse plane. Electromyographic (EMG) activity during the interventions of the anterior deltoid, triceps brachii, biceps brachii, forearm flexors as well as lower abdominal and back stabilizer muscles was collected, and were normalized to maximal voluntary contractions. A two way repeated measures ANOVA (2x3) was conducted to assess the influence of the devices and movement planes on muscle activation. The DOD provided 35.9%, 40.8%, and 52.3% greater anterior deltoid, transverse abdominus (TA)/internal oblique (IO) and lumbo-sacral erector spinae (LSES) activation than did the SOD respectively. Effect size calculations revealed that these differences were of moderate to large magnitude (0.86, 0.48, and 0.61 respectively). There were no significant differences in muscular activation achieved between devices for the triceps brachii, biceps brachii and forearm flexor muscles. Exercise in the transverse plane resulted in 30.5%, 29.5%, and 19.5% greater activation than the sagittal and 21.8%, 17.2%, and 26.3% greater activation than the frontal plane for the anterior deltoid, TA/IO and LSES respectively. A DOD demonstrated greater muscular activity for trunk and shoulder muscle

  5. Heart attack first aid

    Science.gov (United States)

    First aid - heart attack; First aid - cardiopulmonary arrest; First aid - cardiac arrest ... A heart attack occurs when the blood flow that carries oxygen to the heart is blocked. The heart muscle becomes ...

  6. Getting a New Heart

    Science.gov (United States)

    ... a procedure that opens clogged arteries. Repair the heart valve . This procedure can often make your heart function ... heart muscle. Ventricular assist devices (VAD) . These are mechanical pumps that surgeons insert to help the heart ...

  7. Cardiac muscle cell formation after development of the linear heart tube

    NARCIS (Netherlands)

    Kruithof, Boudewijn P. T.; van den Hoff, Maurice J. B.; Wessels, Andy; Moorman, Antoon F. M.

    2003-01-01

    After the development of the linear heart tube, additional myocardium is formed leading to the muscular mantle around the caval and pulmonary veins and the muscular septa in the embryonic heart. Here, we report the results of our in vivo and in vitro studies of this late myocardium-generating

  8. Single ventricle, bicuspid aorta and interatrial wall aneurysm as a rare complex adult congenital heart disease: a case report

    OpenAIRE

    Berisha, Blerim; Krasniqi, Xhevdet; Thaqi, Agim; Gashi, Masar; Ko?inaj, Dardan

    2009-01-01

    Background Single ventricle, bicuspid aortic valve and interatrial wall aneurysm in adulthood are a rare and unique case in medical literature. This presented case with congenital heart disease has never been treated surgically and clinical consequences seriously presented in adulthood. Case presentation A 27 year old man with complex congenital heart disease presented. At the age of six, the single ventricle was ultrasonographly diagnosed, but at age 27 clinical consequences started to be se...

  9. Low Po2 conditions induce reactive oxygen species formation during contractions in single skeletal muscle fibers

    Science.gov (United States)

    Shiah, Amy; Roberts, William J.; Chien, Michael T.; Wagner, Peter D.; Hogan, Michael C.

    2013-01-01

    Contractions in whole skeletal muscle during hypoxia are known to generate reactive oxygen species (ROS); however, identification of real-time ROS formation within isolated single skeletal muscle fibers has been challenging. Consequently, there is no convincing evidence showing increased ROS production in intact contracting fibers under low Po2 conditions. Therefore, we hypothesized that intracellular ROS generation in single contracting skeletal myofibers increases during low Po2 compared with a value approximating normal resting Po2. Dihydrofluorescein was loaded into single frog (Xenopus) fibers, and fluorescence was used to monitor ROS using confocal microscopy. Myofibers were exposed to two maximal tetanic contractile periods (1 contraction/3 s for 2 min, separated by a 60-min rest period), each consisting of one of the following treatments: high Po2 (30 Torr), low Po2 (3–5 Torr), high Po2 with ebselen (antioxidant), or low Po2 with ebselen. Ebselen (10 μM) was administered before the designated contractile period. ROS formation during low Po2 treatment was greater than during high Po2 treatment, and ebselen decreased ROS generation in both low- and high-Po2 conditions (P Po2. Force was reduced >30% for each condition except low Po2 with ebselen, which only decreased ∼15%. We concluded that single myofibers under low Po2 conditions develop accelerated and more oxidative stress than at Po2 = 30 Torr (normal human resting Po2). Ebselen decreases ROS formation in both low and high Po2, but only mitigates skeletal muscle fatigue during reduced Po2 conditions. PMID:23576612

  10. Subcellular distribution of glycogen and decreased tetanic Ca2+ in fatigued single intact mouse muscle fibres

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Cheng, Arthur J; Ørtenblad, Niels

    2014-01-01

    of sarcoplasmic reticulum Ca(2+) release. The aim of the present study was to test directly how the decrease in cytoplasmic free Ca(2+) ([Ca(2+)]i) during repeated tetanic contractions relates to the subcellular glycogen distribution. Single fibres of mouse flexor digitorum brevis muscles were fatigued with 70 Hz......In skeletal muscle fibres, glycogen has been shown to be stored at different subcellular locations: (i) between the myofibrils (intermyofibrillar); (ii) within the myofibrils (intramyofibrillar); and (iii) subsarcolemmal. Of these, intramyofibrillar glycogen has been implied as a critical regulator......, 350 ms tetani given at 2 s (high-intensity fatigue, HIF) or 10 s (low-intensity fatigue, LIF) intervals, while force and [Ca(2+)]i were measured. Stimulation continued until force decreased to 30% of its initial value. Fibres were then prepared for analyses of subcellular glycogen distribution...

  11. NOX2 inhibition impairs early muscle gene expression induced by a single exercise bout

    Directory of Open Access Journals (Sweden)

    Carlos Henríquez-Olguín

    2016-07-01

    Full Text Available Reactive oxygen species (ROS participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2 in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47phox levels were significantly upregulated by exercise in flexor digitorum brevis (FDB. Moreover, exercise significantly increased NOX2 complex assembly (p47phox-gp91phox interaction demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD, glutathione peroxidase (GPx, citrate synthase (CS, mitochondrial transcription factor A (tfam and interleukin-6 (IL-6 in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p<0.001. These results were corroborated using gp91-dstat in an in-vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise.

  12. Inspiratory muscle strength training in infants with congenital heart disease and prolonged mechanical ventilation: a case report.

    Science.gov (United States)

    Smith, Barbara K; Bleiweis, Mark S; Neel, Cimaron R; Martin, A Daniel

    2013-02-01

    Inspiratory muscle strength training (IMST) has been shown to improve maximal pressures and facilitate ventilator weaning in adults with prolonged mechanical ventilation (MV). The purposes of this case report are: (1) to describe the rationale for IMST in infants with MV dependence and (2) to summarize the device modifications used to administer training. Two infants with congenital heart disease underwent corrective surgery and were referred for inspiratory muscle strength evaluation after repeated weaning failures. It was determined that IMST was indicated due to inspiratory muscle weakness and a rapid, shallow breathing pattern. In order to accommodate small tidal volumes of infants, 2 alternative training modes were devised. For infant 1, IMST consisted of 15-second inspiratory occlusions. Infant 2 received 10-breath sets of IMST through a modified positive end-expiratory pressure valve. Four daily IMST sets separated by 3 to 5 minutes of rest were administered 5 to 6 days per week. The infants' IMST tolerance was evaluated by vital signs and daily clinical reviews. Maximal inspiratory pressure (MIP) and rate of pressure development (dP/dt) were the primary outcome measures. Secondary outcome measures included the resting breathing pattern and MV weaning. There were no adverse events associated with IMST. Infants generated training pressures through the adapted devices, with improved MIP, dP/dt, and breathing pattern. Both infants weaned from MV to a high-flow nasal cannula, and neither required subsequent reintubation during their hospitalization. This case report describes pediatric adaptations of an IMST technique used to improve muscle performance and facilitate weaning in adults. Training was well tolerated in 2 infants with postoperative weaning difficulty and inspiratory muscle dysfunction. Further systematic examination will be needed to determine whether IMST provides a significant performance or weaning benefit.

  13. Examination of mitral regurgitation with a goat heart model for the development of intelligent artificial papillary muscle.

    Science.gov (United States)

    Shiraishi, Y; Yambe, T; Yoshizawa, M; Hashimoto, H; Yamada, A; Miura, H; Hashem, M; Kitano, T; Shiga, T; Homma, D

    2012-01-01

    Annuloplasty for functional mitral or tricuspid regurgitation has been made for surgical restoration of valvular diseases. However, these major techniques may sometimes be ineffective because of chamber dilation and valve tethering. We have been developing a sophisticated intelligent artificial papillary muscle (PM) by using an anisotropic shape memory alloy fiber for an alternative surgical reconstruction of the continuity of the mitral structural apparatus and the left ventricular myocardium. This study exhibited the mitral regurgitation with regard to the reduction in the PM tension quantitatively with an originally developed ventricular simulator using isolated goat hearts for the sophisticated artificial PM. Aortic and mitral valves with left ventricular free wall portions of isolated goat hearts (n=9) were secured on the elastic plastic membrane and statically pressurized, which led to valvular leaflet-papillary muscle positional change and central mitral regurgitation. PMs were connected to the load cell, and the relationship between the tension of regurgitation and PM tension were measured. Then we connected the left ventricular specimen model to our hydraulic ventricular simulator and achieved hemodynamic simulation with the controlled tension of PMs.

  14. Loss of a single allele for Ku80 leads to progenitor dysfunction and accelerated aging in skeletal muscle

    Science.gov (United States)

    Didier, Nathalie; Hourdé, Christophe; Amthor, Helge; Marazzi, Giovanna; Sassoon, David

    2012-01-01

    Muscle wasting is a major cause of morbidity in the elderly. Ku80 is required for DNA double strand repair and is implicated in telomere maintenance. Complete loss-of-function leads to reduced post-natal growth and severe progeria in mice. We examined the role of Ku80 in age-related skeletal muscle atrophy. While complete loss of Ku80 leads to pronounced aging in muscle as expected, accompanied by accumulation of DNA damage, loss of a single allele is sufficient to accelerate aging in skeletal muscle although post-natal growth is normal. Ku80 heterozygous muscle shows no DNA damage accumulation but undergoes premature telomere shortening that alters stem cell self-renewal through stress response pathways including p53. These data reveal an unexpected requirement for both Ku80 alleles for optimal progenitor function and prevention of early onset aging in muscle, as well as providing a useful model for therapeutic approaches. PMID:22915554

  15. Exercise training dose differentially alters muscle and heart capillary density and metabolic functions in an obese rat with metabolic syndrome.

    Science.gov (United States)

    Machado, Marcus Vinicius; Vieira, Aline Bomfim; da Conceição, Fabiana Gomes; Nascimento, Alessandro Rodrigues; da Nóbrega, Antonio Claudio Lucas; Tibirica, Eduardo

    2017-12-01

    What is the central question of this study? Regular exercise is recommended as a non-pharmacological approach for the prevention and treatment of metabolic syndrome. However, the impact of different combinations of intensity, duration and frequency of exercise on metabolic syndrome and microvascular density has not been reported. What is the main finding and its importance? We provide evidence on the impact of aerobic exercise dose on metabolic and microvascular alterations in an experimental model of metabolic syndrome induced by high-fat diet. We found that the exercise frequency and duration were the main factors affecting anthropometric and metabolic parameters and microvascular density in the skeletal muscle. Exercise intensity was related only to microvascular density in the heart. We evaluated the effect of the frequency, duration and intensity of exercise training on metabolic parameters and structural capillary density in obese rats with metabolic syndrome. Wistar-Kyoto rats were fed either a standard commercial diet (CON) or a high-fat diet (HFD). Animals that received the HFD were randomly separated into either a sedentary (SED) group or eight different exercise groups that varied according to the frequency, duration and intensity of training. After 12 weeks of aerobic exercise training, the body composition, aerobic capacity, haemodynamic variables, metabolic parameters and capillary density in the heart and skeletal muscle were evaluated. All the exercise training groups showed reduced resting systolic blood pressure and heart rate and normalized fasting glucose. The minimal amount of exercise (90 min per week) produced little effect on metabolic syndrome parameters. A moderate amount of exercise (150 min per week) was required to reduce body weight and improve capillary density. However, only the high amount of exercise (300 min per week) significantly reduced the amount of body fat depots. The three-way ANOVA showed a main effect of exercise

  16. Effects of strain on contractile force and number of sarcomeres in series of Xenopus laevis single muscle fibres during long-term culture

    NARCIS (Netherlands)

    Jaspers, R.T.; Feenstra, Hiske; Verheyen, A.K.; van der Laarse, W.J.; Huijing, P.A.J.B.M.

    2004-01-01

    The aim of the present study is to test whether mechanical strain uniquely regulates muscle fibre atrophy/hypertrophy and adaptation of the number of sarcomeres in series within mature muscle fibres in vitro. Mature single muscle fibres from Xenopus laevis illiofibularis muscle were cultured (4--97

  17. Effects of strain on contractile force and number of sarcomeres in series of Xenopus laevis single muscle fibres during long-term culture

    NARCIS (Netherlands)

    Jaspers, R.T.; Feenstra, H.M.; Verheyen, A.K.; van der Laarse, W.J.; Huijing, P.A.J.B.M.

    2004-01-01

    The aim of the present study is to test whether mechanical strain uniquely regulates muscle fibre atrophy/hypertrophy and adaptation of the number of sarcomeres in series within mature muscle fibres in vitro. Mature single muscle fibres from Xenopus laevis illiofibularis muscle were cultured (4 - 97

  18. Inhibition of pericranial muscle activity, respiration, and heart rate enhances auditory sensitivity

    NARCIS (Netherlands)

    Stekelenburg, J.J.; van Boxtel, A.

    2001-01-01

    We investigated whether previously observed inhibition of pericranial electromyographic (EMG) activity, respiration, and heart rate during sensory intake processes improves auditory sensitivity. Participants had to detect weak auditory stimuli. We found that EMG activity in masticatory and lower

  19. DIFFERENTIAL RESPONSE OF HEAT SHOCK PROTEINS TO UPHILL AND DOWNHILL EXERCISE IN HEART, SKELETAL MUSCLE, LUNG AND KIDNEY TISSUES

    Directory of Open Access Journals (Sweden)

    Pablo C. B. Lollo

    2013-09-01

    Full Text Available Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP, but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric and downhill (predominantly eccentric muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7% and downhill (-7% of inclination. At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK and lactate dehydrogenase (LDH were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal. When the contraction was concentric (uphill and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL-1 in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively. The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus

  20. Divergent muscle sympathetic responses to dynamic leg exercise in heart failure and age-matched healthy subjects.

    Science.gov (United States)

    Notarius, Catherine F; Millar, Philip J; Murai, Hisayoshi; Morris, Beverley L; Marzolini, Susan; Oh, Paul; Floras, John S

    2015-02-01

    People with diminished ventricular contraction who develop heart failure have higher sympathetic nerve firing rates at rest compared with healthy individuals of a similar age and this is associated with less exercise capacity. During handgrip exercise, sympathetic nerve activity to muscle is higher in patients with heart failure but the response to leg exercise is unknown because its recording requires stillness. We measured sympathetic activity from one leg while the other leg cycled at a moderate level and observed a decrease in nerve firing rate in healthy subjects but an increase in subjects with heart failure. Because these nerves release noradrenaline, which can restrict muscle blood flow, this observation helps explain the limited exercise capacity of patients with heart failure. Lower nerve traffic during exercise was associated with greater peak oxygen uptake, suggesting that if exercise training attenuated sympathetic outflow functional capacity in heart failure would improve. The reflex fibular muscle sympathetic nerve (MSNA) response to dynamic handgrip exercise is elicited at a lower threshold in heart failure with reduced ejection fraction (HFrEF). The present aim was to test the hypothesis that the contralateral MSNA response to mild to moderate dynamic one-legged exercise is augmented in HFrEF relative to age- and sex-matched controls. Heart rate (HR), blood pressure and MSNA were recorded in 16 patients with HFrEF (left ventricular ejection fraction = 31 ± 2%; age 62 ± 3 years, mean ± SE) and 13 healthy control subjects (56 ± 2 years) before and during 2 min of upright one-legged unloaded cycling followed by 2 min at 50% of peak oxygen uptake (V̇O2,peak). Resting HR and blood pressure were similar between groups whereas MSNA burst frequency was higher (50.0 ± 2.0 vs. 42.3 ± 2.7 bursts min(-1), P = 0.03) and V̇O2,peak lower (18.0 ± 2.0 vs. 32.6 ± 2.8 ml kg(-1) min(-1), P Exercise increased HR (P exercise in the healthy controls but

  1. Mitochondrial specialization revealed by single muscle fiber proteomics: focus on the Krebs cycle.

    Science.gov (United States)

    Schiaffino, S; Reggiani, C; Kostrominova, T Y; Mann, M; Murgia, M

    2015-12-01

    We have developed a highly sensitive mass spectrometry-based proteomic workflow to examine the proteome of single muscle fibers. This study revealed significant differences in the mitochondrial proteome of the four major fiber types present in mouse skeletal muscle. Here, we focus on Krebs cycle enzymes and in particular on the differential distribution of the two mitochondrial isocitrate dehydrogenases, IDH2 and IDH3. Type 1/slow fibers contain high levels of IDH2 and relatively low levels of IDH3, whereas fast 2X and 2B fibers show an opposite expression pattern. The findings suggest that in skeletal muscle, IDH2 functions in the forward direction of the Krebs cycle and that substrate flux along the cycle occurs predominantly via IDH2 in type 1 fibers and via IDH3 in 2X and 2B fibers. IDH2-mediated conversion of isocitrate to α-ketoglutarate leads to the generation of NADPH, which is critical to buffering the H2O2 produced by the respiratory chain. Nicotinamide nucleotide transhydrogenase (NNT), the other major mitochondrial enzyme involved in NADPH generation, is also more abundant in type 1 fibers. We suggest that the continuously active type 1 fibers are endowed with a more efficient H2O2 scavenging capacity to cope with the higher levels of reactive oxygen species production. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Finite element analysis of mechanics of lateral transmission of force in single muscle fiber.

    Science.gov (United States)

    Zhang, Chi; Gao, Yingxin

    2012-07-26

    Most of the myofibers in long muscles of vertebrates terminate within fascicles without reaching either end of the tendon, thus force generated in myofibers has to be transmitted laterally through the extracellular matrix (ECM) to adjacent fibers; which is defined as the lateral transmission of force in skeletal muscles. The goal of this study was to determine the mechanisms of lateral transmission of force between the myofiber and ECM. In this study, a 2D finite element model of single muscle fiber was developed to study the effects of mechanical properties of the endomysium and the tapered ends of myofiber on lateral transmission of force. Results showed that most of the force generated is transmitted near the end of the myofiber through shear to the endomysium, and the force transmitted to the end of the model increases with increased stiffness of ECM. This study also demonstrated that the tapered angle of the myofiber ends can reduce the stress concentration near the myofiber end while laterally transmitting force efficiently. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Factors affecting growth in infants with single ventricle physiology: a report from the Pediatric Heart Network Infant Single Ventricle Trial.

    Science.gov (United States)

    Williams, Richard V; Zak, Victor; Ravishankar, Chitra; Altmann, Karen; Anderson, Jeffrey; Atz, Andrew M; Dunbar-Masterson, Carolyn; Ghanayem, Nancy; Lambert, Linda; Lurito, Karen; Medoff-Cooper, Barbara; Margossian, Renee; Pemberton, Victoria L; Russell, Jennifer; Stylianou, Mario; Hsu, Daphne

    2011-12-01

    To describe growth patterns in infants with single ventricle physiology and determine factors influencing growth. Data from 230 subjects enrolled in the Pediatric Heart Network Infant Single Ventricle Enalapril Trial were used to assess factors influencing change in weight-for-age z-score (z) from study enrollment (0.7 ± 0.4 months) to pre-superior cavopulmonary connection (SCPC; 5.1 ± 1.8 months, period 1) and pre-SCPC to final study visit (14.1 ± 0.9 months, period 2). Predictor variables included patient characteristics, feeding regimen, clinical center, and medical factors during neonatal (period 1) and SCPC hospitalizations (period 2). Univariate regression analysis was performed, followed by backward stepwise regression and bootstrapping reliability to inform a final multivariable model. Weights were available for 197 of 230 subjects for period 1 and 173 of 197 subjects for period 2. For period 1, greater gestational age, younger age at study enrollment, tube feeding at neonatal hospitalization discharge, and clinical center were associated with a greater negative z (poorer growth) in multivariable modeling (adjusted R(2) = 0.39, P SCPC and greater daily caloric intake were associated with greater positive z (better growth; R(2) = 0.10, P = .002). Aggressive nutritional support and earlier SCPC are modifiable factors associated with a favorable change in weight-for-age z-score. Copyright © 2011 Mosby, Inc. All rights reserved.

  4. Factors Impacting Growth in Infants with Single Ventricle Physiology: A Report from Pediatric Heart Network Infant Single Ventricle Trial

    Science.gov (United States)

    Williams, Richard V.; Zak, Victor; Ravishankar, Chitra; Altmann, Karen; Anderson, Jeffrey; Atz, Andrew M.; Dunbar-Masterson, Carolyn; Ghanayem, Nancy; Lambert, Linda; Lurito, Karen; Medoff-Cooper, Barbara; Margossian, Renee; Pemberton, Victoria L.; Russell, Jennifer; Stylianou, Mario; Hsu, Daphne

    2011-01-01

    Objectives To describe growth patterns in infants with single ventricle physiology and determine factors influencing growth. Study design Data from 230 subjects enrolled in the Pediatric Heart Network Infant Single Ventricle Enalapril Trial were used to assess factors influencing change in weight-for-age z-score (Δz) from study enrollment (0.7 ± 0.4 months) to pre-superior cavopulmonary connection (SCPC) (5.1 ± 1.8 months, period 1), and pre-SCPC to final study visit (14.1 ± 0.9 months, period 2). Predictor variables included patient characteristics, feeding regimen, clinical center, and medical factors during neonatal (period 1) and SCPC hospitalizations (period 2). Univariate regression analysis was performed, followed by backward stepwise regression and bootstrapping reliability to inform a final multivariable model. Results Weights were available for 197/230 subjects for period 1 and 173/197 for period 2. For period 1, greater gestational age, younger age at study enrollment, tube feeding at neonatal discharge, and clinical center were associated with a greater negative Δz (poorer growth) in multivariable modeling (adjusted R2 = 0.39, p SCPC and greater daily caloric intake were associated with greater positive Δz (better growth) (R2 = 0.10, p = 0.002). Conclusions Aggressive nutritional support and earlier SCPC are modifiable factors associated with a favorable change in weight-for-age z-score. PMID:21784436

  5. Congenital heart defects in newborns with apparently isolated single gastrointestinal malformation: A retrospective study.

    Science.gov (United States)

    Schierz, Ingrid Anne Mandy; Pinello, Giuseppa; Giuffrè, Mario; La Placa, Simona; Piro, Ettore; Corsello, Giovanni

    2016-12-01

    Congenital gastrointestinal system malformations/abdominal wall defects (GISM) may appear as isolated defects (single or complex), or in association with multiple malformations. The high incidence of association of GISM and congenital heart defects (CHD) in patients with syndromes and malformative sequences is known, but less expected is the association of apparently isolated single GISM and CHD. The aim of this study was to investigate the frequency of CHD in newborns with isolated GISM, and the possibility to modify the diagnostic-therapeutic approach just before the onset of cardiac symptoms or complications. Anamnestic, clinical, and imaging data of newborns requiring abdominal surgery for GISM, between 2009 and 2014, were compared with a control group of healthy newborns. Distribution of GISM and cardiovascular abnormalities were analyzed, and risk factors for adverse outcomes were identified. Seventy-one newborns with isolated GISM were included in this study. More frequent GISM were intestinal rotation and fixation disorders. CHD were observed in 15.5% of patients, augmenting their risk for morbidity. Risk factors for morbidity related to sepsis were identified in central venous catheter, intestinal stoma, and H2-inhibitor-drugs. Moreover, 28.2% of newborns presented only functional cardiac disorders but an unexpectedly higher mortality. The high incidence of congenital heart disease in infants with apparently isolated GISM confirms the need to perform an echocardiographic study before surgery to improve perioperative management and prevent complications such as sepsis and endocarditis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Bion 11 Spaceflight Project: Effect of Weightlessness on Single Muscle Fiber Function in Rhesus Monkeys

    Science.gov (United States)

    Fitts, Robert H.; Romatowski, Janell G.; Widrick, Jeffrey J.; DeLaCruz, Lourdes

    1999-01-01

    Although it is well known that microgravity induces considerable limb muscle atrophy, little is known about how weightlessness alters cell function. In this study, we investigated how weightlessness altered the functional properties of single fast and slow striated muscle fibers. Physiological studies were carried out to test the hypothesis that microgravity causes fiber atrophy, a decreased peak force (Newtons), tension (Newtons/cross-sectional area) and power, an elevated peak rate of tension development (dp/dt), and an increased maximal shortening velocity (V(sub o)) in the slow type I fiber, while changes in the fast-twitch fiber are restricted to atrophy and a reduced peak force. For each fiber, we determined the peak force (P(sub o)), V(sub o), dp/dt, the force-velocity relationship, peak power, the power-force relationship, the force-pCa relationship, and fiber stiffness. Biochemical studies were carried out to assess the effects of weightlessness on the enzyme and substrate profile of the fast- and slow-twitch fibers. We predicted that microgravity would increase resting muscle glycogen and glycolytic metabolism in the slow fiber type, while the fast-twitch fiber enzyme profile would be unaltered. The increased muscle glycogen would in part result from an elevated hexokinase and glycogen synthase. The enzymes selected for study represent markers for mitochondrial function (citrate synthase and 0-hydroxyacyl-CoA dehydrogenase), glycolysis (Phosphofructokinase and lactate dehydrogenase), and fatty acid transport (Carnitine acetyl transferase). The substrates analyzed will include glycogen, lactate, adenosine triphosphate, and phosphocreatine.

  7. Position control of a single pneumatic artificial muscle with hysteresis compensation based on modified Prandtl-Ishlinskii model.

    Science.gov (United States)

    Zang, Xizhe; Liu, Yixiang; Heng, Shuai; Lin, Zhenkun; Zhao, Jie

    2017-01-01

    High-performance position control of pneumatic artificial muscles is limited by their inherent nonlinearity and hysteresis. This study aims to model the length/pressure hysteresis of a single pneumatic artificial muscle and to realize its accurate position tracking control with forward hysteresis compensation. The classical Prandtl-Ishlinskii model is widely used in hysteresis modelling and compensation. But it is only effective for symmetric hysteresis. Therefore, a modified Prandtl-Ishlinskii model is built to characterize the asymmetric length/pressure hysteresis of a single pneumatic artificial muscle, by replacing the classical play operators with two more flexible elementary operators to independently describe the ascending branch and descending branch of hysteresis loops. On the basis, a position tracking controller, which is composed of cascade forward hysteresis compensation and simple proportional pressure controller, is designed for the pneumatic artificial muscle. Experiment results show that the MPI model can reproduce the length/pressure hysteresis of the pneumatic artificial muscle, and the proposed controller for the pneumatic artificial muscle can track the reference position signals with high accuracy. By modelling the length/pressure hysteresis with the modified Prandtl-Ishlinskii model and using its inversion for compensation, precise position control of a single pneumatic artificial muscle is achieved.

  8. Increasing temperature speeds intracellular PO2 kinetics during contractions in single Xenopus skeletal muscle fibers.

    Science.gov (United States)

    Koga, S; Wüst, R C I; Walsh, B; Kindig, C A; Rossiter, H B; Hogan, M C

    2013-01-01

    Precise determination of the effect of muscle temperature (T(m)) on mitochondrial oxygen consumption kinetics has proven difficult in humans, in part due to the complexities in controlling for T(m)-related variations in blood flow, fiber recruitment, muscle metabolism, and contractile properties. To address this issue, intracellular Po(2) (P(i)(O(2))) was measured continuously by phosphorescence quenching following the onset of contractions in single Xenopus myofibers (n = 24) while controlling extracellular temperature. Fibers were subjected to two identical contraction bouts, in random order, at 15°C (cold, C) and 20°C (normal, N; n = 12), or at N and 25°C (hot, H; n = 12). Contractile properties were determined for every contraction. The time delay of the P(i)(O(2)) response was significantly greater in C (59 ± 35 s) compared with N (35 ± 26 s, P = 0.01) and H (27 ± 14 s, P = 0.01). The time constant for the decline in P(i)(O(2)) was significantly greater in C (89 ± 34 s) compared with N (52 ± 15 s; P kinetics and T(m) (r = 0.322, P = 0.03). Estimated ATP turnover was significantly greater in H than in C (P kinetics among conditions. These results demonstrate that P(i)(O(2)) kinetics in single contracting myofibers are dependent on T(m), likely caused by temperature-induced differences in metabolic demand and by temperature-dependent processes underlying mitochondrial activation at the start of muscle contractions.

  9. Myosin content of single muscle fibers following short-term disuse and active recovery in young and old healthy men

    DEFF Research Database (Denmark)

    Hvid, Lars G; Brocca, Lorenza; Ørtenblad, Niels

    2017-01-01

    Short-term disuse and subsequent recovery affect whole muscle and single myofiber contractile function in young and old. While the loss and recovery of single myofiber specific force (SF) following disuse and rehabilitation has been shown to correlate with alterations in myosin concentrations...

  10. Cyclic AMP-dependent signaling system is a primary metabolic target for non-thermal effect of microwaves on heart muscle hydration.

    Science.gov (United States)

    Narinyan, Lilia; Ayrapetyan, Sinerik

    2017-01-01

    Previously, we have suggested that cell hydration is a universal and extra-sensitive sensor for the structural changes of cell aqua medium caused by the impact of weak chemical and physical factors. The aim of present work is to elucidate the nature of the metabolic messenger through which physiological solution (PS) treated by non-thermal (NT) microwaves (MW) could modulate heart muscle hydration of rats. For this purpose, the effects of NT MW-treated PS on heart muscle hydration, [ 3 H]-ouabain binding with cell membrane, 45 Ca 2+ uptake and intracellular cyclic nucleotides contents in vivo and in vitro experiments were studied. It is shown that intraperitoneal injections of both Sham-treated PS and NT MW-treated PS elevate heart muscle hydration. However, the effect of NT MW-treated PS on muscle hydration is more pronounced than the effect of Sham-treated PS. In vitro experiments NT MW-treated PS has dehydration effect on muscle, which is not changed by decreasing Na + gradients on membrane. Intraperitoneal injection of Sham- and NT MW-treated PS containing 45 Ca 2+ have similar dehydration effect on muscle, while NT MW-treated PS has activation effect on Na + /Ca 2+ exchange in reverse mode. The intraperitoneal injection of NT MW-treated PS depresses [ 3 H]-ouabain binding with its high-affinity membrane receptors, elevates intracellular cAMP and decreases cGMP contents. Based on the obtained data, it is suggested that cAMP-dependent signaling system serves as a primary metabolic target for NT MW effect on heart muscle hydration.

  11. Body, heart, thyroid gland and skeletal muscle weight changes in rats with altered thyroid status

    Czech Academy of Sciences Publication Activity Database

    Soukup, Tomáš; Zachařová, Gisela; Smerdu, V.; Jirmanová, Isa

    2001-01-01

    Roč. 50, č. 6 (2001), s. 619-626 ISSN 0862-8408 R&D Projects: GA ČR GA304/00/1653 Institutional research plan: CEZ:AV0Z5011922 Keywords : thyroid state * skeletal muscles * body and organ weight Subject RIV: FH - Neurology Impact factor: 1.027, year: 2001

  12. Elevation in heat shock protein 72 mRNA following contractions in isolated single skeletal muscle fibers

    OpenAIRE

    Stary, Creed M.; Walsh, Brandon J.; Knapp, Amy E.; Brafman, David; Hogan, Michael C.

    2008-01-01

    The purpose of the present study was 1) to develop a stable model for measuring contraction-induced elevations in mRNA in single skeletal muscle fibers and 2) to utilize this model to investigate the response of heat shock protein 72 (HSP72) mRNA following an acute bout of fatiguing contractions. Living, intact skeletal muscle fibers were microdissected from lumbrical muscle of Xenopus laevis and either electrically stimulated for 15 min of tetanic contractions (EX; n = 26) or not stimulated ...

  13. A Cycle Ergometer Exercise Program Improves Exercise Capacity and Inspiratory Muscle Function in Hospitalized Patients Awaiting Heart Transplantation: a Pilot Study

    Directory of Open Access Journals (Sweden)

    Patrícia Forestieri

    Full Text Available Abstract Objective: The purpose of this study was to evaluate the effect of a cycle ergometer exercise program on exercise capacity and inspiratory muscle function in hospitalized patients with heart failure awaiting heart transplantation with intravenous inotropic support. Methods: Patients awaiting heart transplantation were randomized and allocated prospectively into two groups: 1 Control Group (n=11 - conventional protocol; and 2 Intervention Group (n=7 - stationary cycle ergometer exercise training. Functional capacity was measured by the six-minute walk test and inspiratory muscle strength assessed by manovacuometry before and after the exercise protocols. Results: Both groups demonstrated an increase in six-minute walk test distance after the experimental procedure compared to baseline; however, only the intervention group had a significant increase (P =0.08 and P =0.001 for the control and intervention groups, respectively. Intergroup comparison revealed a greater increase in the intervention group compared to the control (P <0.001. Regarding the inspiratory muscle strength evaluation, the intragroup analysis demonstrated increased strength after the protocols compared to baseline for both groups; statistical significance was only demonstrated for the intervention group, though (P =0.22 and P <0.01, respectively. Intergroup comparison showed a significant increase in the intervention group compared to the control (P <0.01. Conclusion: Stationary cycle ergometer exercise training shows positive results on exercise capacity and inspiratory muscle strength in patients with heart failure awaiting cardiac transplantation while on intravenous inotropic support.

  14. Bovine cytochrome c oxidases, purified from heart, skeletal muscle, liver and kidney, differ in the small subunits but show the same reaction kinetics with cytochrome c

    NARCIS (Netherlands)

    Sinjorgo, K. M.; Durak, I.; Dekker, H. L.; Edel, C. M.; Hakvoort, T. B.; van Gelder, B. F.; Muijsers, A. O.

    1987-01-01

    (1) Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate of purified cytochrome c oxidase preparations revealed that bovine kidney, skeletal muscle and heart contain different cytochrome c oxidase isoenzymes, which show differences in mobility of the subunits encoded by the

  15. Inspiratory work capacity is more severely depressed than inspiratory muscle strength in patients with heart failure: Novel applications for inspiratory muscle training.

    Science.gov (United States)

    Laoutaris, Ioannis D; Adamopoulos, Stamatis; Manginas, Athanassios; Panagiotakos, Demosthenes B; Cokkinos, Dennis V; Dritsas, Athanasios

    2016-10-15

    We hypothesized that the ability to sustain maximal inspiratory pressure (SPImax) over time as a measure of work capacity may be more severely affected than inspiratory muscle strength (PImax) in patients with heart failure (HF). We retrospectively investigated eighty patients with HF, NYHA II/III/ ambulatoryIV and a (mean±SD) LVEF 27±8%, and compared them to 25 healthy subjects (HS). During a maximal inspiratory manoeuvre from residual volume (RV) to total lung capacity, PImax was measured as the maximum mouth pressure at RV, inspiratory contraction time (ICT) as the time from RV to end of inspiration and SPImax as the area under a pressure-time curve using an electronic pressure manometer with designed-purpose software (Trainair(®), Project Electronics Ltd., London, UK). Exercise capacity was assessed with cardiopulmonary exercise testing and the 6-minute walk test (6MWT). Patients achieved a (mean±SD) peak VO2=15.7±3.4ml/kg/min and 6MWT=338±88m. PImax, ICT and SPImax were reduced in HF pts at 75%***, 61%*** and 52%*** of HS, and correlated with NYHA (r=-0.485***), (r=-0.507**), (r=-0.500***), peakVO2 (r=0.501***), (r=0.655***), (r=0.508***) and 6MWT (r=0.477***), (r=0.345**), (r=0.530***), respectively (*pinspiratory muscle training. Equations are provided to predict SPImax in relation to age and exercise capacity in HF. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Cone beam tomography of the heart using single-photon emission-computed tomography

    International Nuclear Information System (INIS)

    Gullberg, G.T.; Christian, P.E.; Zeng, G.L.; Datz, F.L.; Morgan, H.T.

    1991-01-01

    The authors evaluated cone beam single-photon emission-computed tomography (SPECT) of the heart. A new cone beam reconstruction algorithm was used to reconstruct data collected from short scan acquisitions (of slightly more than 180 degrees) of a detector anteriorally traversing a noncircular orbit. The less than 360 degrees acquisition was used to minimize the attenuation artifacts that result from reconstructing posterior projections of 201T1 emissions from the heart. The algorithm includes a new method for reconstructing truncated projections of background tissue activity that eliminates reconstruction ring artifacts. Phantom and patient results are presented which compare a high-resolution cone beam collimator (50-cm focal length; 6.0-mm full width at half maximum [FWHM] at 10 cm) to a low-energy general purpose (LEGP) parallel hole collimator (8.2-mm FWHM at 10 cm) which is 1.33 times more sensitive. The cone beam tomographic results are free of reconstruction artifacts and show improved spatial and contrast resolution over that obtained with the LEGP parallel hole collimator. The limited angular sampling restrictions and truncation problems associated with cone beam tomography do not deter from obtaining diagnostic information. However, even though these preliminary results are encouraging, a thorough clinical study is still needed to investigate the specificity and sensitivity of cone beam tomography

  17. Ventricular Assist Device in Single-Ventricle Heart Disease and a Superior Cavopulmonary Anastomosis.

    Science.gov (United States)

    Niebler, Robert A; Shah, Tejas K; Mitchell, Michael E; Woods, Ronald K; Zangwill, Steven D; Tweddell, James S; Berger, Stuart; Ghanayem, Nancy S

    2016-02-01

    Our objective is to describe the use of a ventricular assist device (VAD) in single-ventricle patients with circulatory failure following superior cavopulmonary anastomosis (SCPA). We performed a retrospective chart review of all single-ventricle patients supported with a VAD following SCPA. Implantation techniques, physiologic parameters while supported, medical and surgical interventions postimplant, and outcomes were reviewed. Four patients were supported with an EXCOR Pediatric (Berlin Heart Inc., The Woodlands, TX, USA) following SCPA for a median duration of 10.5 days (range 9-312 days). Selective excision of trabeculae and chords facilitated apical cannulation in all patients without inflow obstruction. There were two pump exchanges in the one patient supported for 312 days. Two patients were evaluated by cardiac catheterization while supported. Three of four patients were successfully bridged to transplantation. One patient died while supported. All patients had significant bleeding at the time of transplantation, and one required posttransplant extracorporeal membrane oxygenation with subsequent full recovery. VAD support can provide a successful bridge to transplantation in patients with single-ventricle circulation following SCPA. A thorough understanding of the challenges encountered during this support is necessary for successful outcomes. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  18. Comparative in vitro metabolism of 1-14C-oleic acid and 1-14C-erucic acid in liver, heart and skeletal muscles of rats

    International Nuclear Information System (INIS)

    Bhatia, I.S.; Sharma, A.K.; Ahuja, S.P.

    1978-01-01

    In vitro oxidation of 14 C-oleic and 1- 14 C-erucic acid and their incorporation into lipids by liver, heart and skeletal muscles from female albino rats were studied. These tissues were obtained from rats maintained for 120 days on low fat diet or diets containing 15% mustard oil or 15% groundnut oil. In all these tissues from rats on different types of diets, the oxidation of 1- 14 C-erucic acid was lower than that 1- 14 C-oleic acid. There was little accumulation of lipids in heart after 120 days of feeding mustard oil. Oxidation of 1- 14 C-erucic acid was enhanced in liver, heart and skeletal muscles of rats conditioned to the mustard oil diet supplying erucic acid. Oxidation of erucic acid was maximum in liver and least in heart, whereas there were no differences in the oxidation of 1- 14 C-oleic acid in these tissues. Incorporation of 1- 14 C-oleic acid into triglycerides and phospholipids was not affected by the type of diet or tissues Incorporation of 1- 14 C-erucic acid was mainly into triglycerides of heart and skeletal muscles of rats not accustomed to mustard oil diet whereas these tissues from rats accustomed to mustard oil diets incorporated 1- 14 C-erucic acid both into the triglycerides and phospholipids. (author)

  19. Building a comprehensive team for the longitudinal care of single ventricle heart defects: Building blocks and initial results.

    Science.gov (United States)

    Texter, Karen; Davis, Jo Ann M; Phelps, Christina; Cheatham, Sharon; Cheatham, John; Galantowicz, Mark; Feltes, Timothy F

    2017-07-01

    With increasing survival of children with HLHS and other single ventricle lesions, the complexity of medical care for these patients is substantial. Establishing and adhering to best practice models may improve outcome, but requires careful coordination and monitoring. In 2013 our Heart Center began a process to build a comprehensive Single Ventricle Team designed to target these difficult issues. Comprehensive Single Ventricle Team in 2014 was begun, to standardize care for children with single ventricle heart defects from diagnosis to adulthood within our institution. The team is a multidisciplinary group of providers committed to improving outcomes and quality of life for children with single ventricle heart defects, all functioning within the medical home of our heart center. Standards of care were developed and implemented in five target areas to standardize medical management and patient and family support. Under the team 100 patients have been cared for. Since 2014 a decrease in interstage mortality for HLHS were seen. Using a team approach and the tools of Quality Improvement they have been successful in reaching high protocol compliance for each of these areas. This article describes the process of building a successful Single Ventricle team, our initial results, and lessons learned. Additional study is ongoing to demonstrate the effects of these interventions on patient outcomes. © 2017 Wiley Periodicals, Inc.

  20. Genetic mapping of human heart-skeletal muscle adenine nucleotide translocator and its relationship to the facioscapulohumeral muscular dystrophy locus

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Y.; Chung, A.B.; Torroni, A.; Stepien, G.; Shoffner, J.M.; Costigan, D.A.; Polak, M. [Emory Univ. School of Medicine, Atlanta, GA (United States); Wasmuth, J.J.; Altherr, M.R.; Winokur, S.T. [Univ. of California, Irvine, CA (United States)] [and others

    1993-05-01

    The mitochondrial heart-skeletal muscle adenine nucleotide translocator (ANT1) was regionally mapped to 4q35-qter using somatic cell hybrids containing deleted chromosome 4. The regional location was further refined through family studies using ANT1 intron and promoter nucleotide polymorphisms recognized by the restriction endonucleases MboII, NdeI, and HaeIII. Two alleles were found, each at a frequency of 0.5. The ANT1 locus was found to be closely linked to D4S139, D4S171, and the dominant skeletal muscle disease locus facioscapulohumeral muscular dystrophy (FSHD). A crossover that separated D4S171 and ANT1 from D4S139 was found. Since previous studies have established the chromosome 4 map order as centromere-D4S171-D4S139-FSHD, it was concluded that ANT1 is located on the side of D4S139, that is opposite from FSHD. This conclusion was confirmed by sequencing the exons and analyzing the transcripts of ANT1 from several FSHD patients and finding no evidence of aberration. 35 refs., 5 figs., 1 tab.

  1. Muscle power failure in mobility-limited adults: preserved single muscle fibre function despite reduced whole muscle size, quality and neuromuscular activiation

    Science.gov (United States)

    This study investigated the physiological and gender determinants of the age-related loss of muscle power in 31 healthy middle-aged adults (aged 40-55 years), 28 healthy older adults (70-85 years) and 34 mobility-limited older adults (70-85 years). We hypothesized that leg extensor muscle power woul...

  2. Atomic force microscope observation of branching in single transcript molecules derived from human cardiac muscle

    Science.gov (United States)

    Reed, Jason; Hsueh, Carlin; Mishra, Bud; Gimzewski, James K.

    2008-09-01

    We have used an atomic force microscope to examine a clinically derived sample of single-molecule gene transcripts, in the form of double-stranded cDNA, (c: complementary) obtained from human cardiac muscle without the use of polymerase chain reaction (PCR) amplification. We observed a log-normal distribution of transcript sizes, with most molecules being in the range of 0.4-7.0 kilobase pairs (kb) or 130-2300 nm in contour length, in accordance with the expected distribution of mRNA (m: messenger) sizes in mammalian cells. We observed novel branching structures not previously known to exist in cDNA, and which could have profound negative effects on traditional analysis of cDNA samples through cloning, PCR and DNA sequencing.

  3. Foot muscle morphology is related to center of pressure sway and control mechanisms during single-leg standing.

    Science.gov (United States)

    Zhang, Xianyi; Schütte, Kurt Heinrich; Vanwanseele, Benedicte

    2017-09-01

    Maintaining balance is vitally important in everyday life. Investigating the effects of individual foot muscle morphology on balance may provide insights into neuromuscular balance control mechanisms. This study aimed to examine the correlation between the morphology of foot muscles and balance performance during single-leg standing. Twenty-eight recreational runners were recruited in this study. An ultrasound device was used to measure the thickness and cross-sectional area of three intrinsic foot muscles (abductor hallucis, flexor digitorum brevis and quadratus plantae) and peroneus muscles. Participants were required to perform 30s of single-leg standing for three trials on a force plate, which was used to record the center of pressure (COP). The standard deviation of the amplitude and ellipse area of the COP were calculated. In addition, stabilogram diffusion analysis (SDA) was performed on COP data. Pearson correlation coefficients were computed to examine the correlation between foot muscle morphology and traditional COP parameters as well as with SDA parameters. Our results showed that larger abductor hallucis correlated to smaller COP sway, while larger peroneus muscles correlated to larger COP sway during single-leg standing. Larger abductor hallucis also benefited open-loop dynamic stability, as well as supported a more efficient transfer from open-loop to closed loop control mechanisms. These results suggest that the morphology of foot muscles plays an important role in balance performance, and that strengthening the intrinsic foot muscles may be an effective way to improve balance. Copyright © 2017. Published by Elsevier B.V.

  4. Detection of muscle wasting in patients with chronic heart failure using C-terminal agrin fragment: results from the Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF).

    Science.gov (United States)

    Steinbeck, Lisa; Ebner, Nicole; Valentova, Miroslava; Bekfani, Tarek; Elsner, Sebastian; Dahinden, Pius; Hettwer, Stefan; Scherbakov, Nadja; Schefold, Jörg C; Sandek, Anja; Springer, Jochen; Doehner, Wolfram; Anker, Stefan D; von Haehling, Stephan

    2015-12-01

    Skeletal muscle wasting affects 20% of patients with chronic heart failure and has serious implications for their activities of daily living. Assessment of muscle wasting is technically challenging. C-terminal agrin-fragment (CAF), a breakdown product of the synaptically located protein agrin, has shown early promise as biomarker of muscle wasting. We sought to investigate the diagnostic properties of CAF in muscle wasting among patients with heart failure. We assessed serum CAF levels in 196 patients who participated in the Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF). Muscle wasting was identified using dual-energy X-ray absorptiometry (DEXA) in 38 patients (19.4%). Patients with muscle wasting demonstrated higher CAF values than those without (125.1 ± 59.5 pmol/L vs. 103.8 ± 42.9 pmol/L, P = 0.01). Using receiver operating characteristics (ROC), we calculated the optimal CAF value to identify patients with muscle wasting as >87.5 pmol/L, which had a sensitivity of 78.9% and a specificity of 43.7%. The area under the ROC curve was 0.63 (95% confidence interval 0.56-0.70). Using simple regression, we found that serum CAF was associated with handgrip (R = - 0.17, P = 0.03) and quadriceps strength (R = - 0.31, P < 0.0001), peak oxygen consumption (R = - 0.5, P < 0.0001), 6-min walk distance (R = - 0.32, P < 0.0001), and gait speed (R = - 0.2, P = 0.001), as well as with parameters of kidney and liver function, iron metabolism and storage. CAF shows good sensitivity for the detection of skeletal muscle wasting in patients with heart failure. Its assessment may be useful to identify patients who should undergo additional testing, such as detailed body composition analysis. As no other biomarker is currently available, further investigation is warranted. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.

  5. Carnosine and anserine homeostasis in skeletal muscle and heart is controlled by β‐alanine transamination

    Science.gov (United States)

    Blancquaert, Laura; Baba, Shahid P.; Kwiatkowski, Sebastian; Stautemas, Jan; Stegen, Sanne; Barbaresi, Silvia; Chung, Weiliang; Boakye, Adjoa A.; Hoetker, J. David; Bhatnagar, Aruni; Delanghe, Joris; Vanheel, Bert; Veiga‐da‐Cunha, Maria; Derave, Wim

    2016-01-01

    Key points Using recombinant DNA technology, the present study provides the first strong and direct evidence indicating that β‐alanine is an efficient substrate for the mammalian transaminating enzymes 4‐aminobutyrate‐2‐oxoglutarate transaminase and alanine‐glyoxylate transaminase.The concentration of carnosine and anserine in murine skeletal and heart muscle depends on circulating availability of β‐alanine, which is in turn controlled by degradation of β‐alanine in liver and kidney.Chronic oral β‐alanine supplementation is a popular ergogenic strategy in sports because it can increase the intracellular carnosine concentration and subsequently improve the performance of high‐intensity exercises. The present study can partly explain why the β‐alanine supplementation protocol is so inefficient, by demonstrating that exogenous β‐alanine can be effectively routed toward oxidation. Abstract The metabolic fate of orally ingested β‐alanine is largely unknown. Chronic β‐alanine supplementation is becoming increasingly popular for improving high‐intensity exercise performance because it is the rate‐limiting precursor of the dipeptide carnosine (β‐alanyl‐l‐histidine) in muscle. However, only a small fraction (3–6%) of the ingested β‐alanine is used for carnosine synthesis. Thus, the present study aimed to investigate the putative contribution of two β‐alanine transamination enzymes, namely 4‐aminobutyrate‐2‐oxoglutarate transaminase (GABA‐T) and alanine‐glyoxylate transaminase (AGXT2), to the homeostasis of carnosine and its methylated analogue anserine. We found that, when transfected into HEK293T cells, recombinant mouse and human GABA‐T and AGXT2 are able to transaminate β‐alanine efficiently. The reaction catalysed by GABA‐T is inhibited by vigabatrin, whereas both GABA‐T and AGXT2 activity is inhibited by aminooxyacetic acid (AOA). Both GABA‐T and AGXT2 are highly expressed in the mouse liver and

  6. Pre-embedding staining of single muscle fibers for light and electron microscopy studies of subcellular organization

    DEFF Research Database (Denmark)

    Ralston, E; Ploug, Thorkil

    1996-01-01

    ) immunocytochemistry. Here we show that pre-embedding staining of single teased fibers, or of single enzymatically dissociated fibers, has several advantages over the use of sections for observing discrete patterns that extend over long distances in the cells. We report on an optimization study carried out......Skeletal muscle fibers are large, multinucleated cells which pose a challenge to the morphologist. In the course of studies of the distribution of the glucose transporter GLUT4, in muscle, we have compared different preparative procedures, for both light (LM) and electron microscopy (EM...

  7. Single-Trial EEG-EMG coherence analysis reveals muscle fatigue-related progressive alterations in corticomuscular coupling.

    Science.gov (United States)

    Siemionow, Vlodek; Sahgal, Vinod; Yue, Guang H

    2010-04-01

    Voluntary muscle fatigue is a progressive process. A recent study demonstrated muscle fatigue-induced weakening of functional corticomuscular coupling measured by coherence between the brain [electroencephalogram (EEG)] and muscle [electromyogram (EMG)] signals after a relatively long-duration muscle contraction. Comparing the EEG-EMG coherence before versus after fatigue or between data of two long-duration time blocks is not adequate to reveal the dynamic nature of the fatigue process. The purpose of this study was to address this issue by quantifying single-trial EEG-EMG coherence and EEG, EMG power based on wavelet transform. Eight healthy subjects performed 200 maximal intermittent handgrip contractions in a single session with handgrip force, EEG and EMG signals acquired simultaneously. The EEG and EMG data during each 2-s handgrip was subjected to single trial EEG-EMG wavelet energy spectrum and coherence computation. The EEG-EMG coherence and energy spectrum at beta (15 ~ 35 Hz) and gamma (35-50 Hz) frequency bands were statistically analyzed in 2-block (75 trials per block), 5-block (30 trials/block), and 10-block (15 trials/block) data settings. The energy of both the EEG and EMG signals decreased significantly with muscle fatigue. The EEG-EMG coherence had a significant reduction for the 2-block comparison. More detailed dynamical changing and inter-subject variation of the EEG-EMG coherence and energy were revealed by 5- and 10-block comparisons. These results show feasibility of wavelet transform-based measurement of the EEG-EMG coherence and corresponding energy based on single-trial data, which provides extra information to demonstrate a time course of dynamic adaptations of the functional corticomuscular coupling, as well as brain and muscle signals during muscle fatigue.

  8. Blood pressure and heart rate effects following a single dose of bitter orange.

    Science.gov (United States)

    Bui, Linda T; Nguyen, DiemThuy T; Ambrose, Peter J

    2006-01-01

    The ingredients of numerous "ephedra-free" dietary supplements used for weight loss include bitter orange, which contains sympathomimetic alkaloids such as synephrine. Due to the similarity in chemical structure to ephedrine and the potential sympathomimetic effects of synephrine, it is hypothesized that bitter orange may increase blood pressure (BP) and heart rate (HR). To determine the effects on BP and HR after a single dose of bitter orange in healthy adults. In a prospective, randomized, double-blind, placebo-controlled, crossover study, 15 young, healthy, adult subjects received either a single dose of Nature's Way Bitter Orange--a 900 mg dietary supplement extract standardized to 6% synephrine--or matching placebo, with a one week washout period. Systolic BP (SBP), diastolic BP (DBP), and HR were measured at baseline and every hour for 6 hours after administration. SBP after bitter orange was significantly increased versus placebo at hours 1-5 (p bitter orange, DBP after bitter orange was significantly increased versus placebo at hours 4 and 5 (p bitter orange versus placebo for hours 2-5 (p bitter orange versus placebo in young, healthy adults.

  9. Structural cerebral abnormalities and neurodevelopmental status in single ventricle congenital heart disease before Fontan procedure.

    Science.gov (United States)

    Knirsch, Walter; Mayer, Kristina Nadine; Scheer, Ianina; Tuura, Ruth; Schranz, Dietmar; Hahn, Andreas; Wetterling, Kristina; Beck, Ingrid; Latal, Beatrice; Reich, Bettina

    2017-04-01

    Neonates with single ventricle congenital heart disease are at risk for structural cerebral abnormalities. Little is known about the further evolution of cerebral abnormalities until Fontan procedure. Between August 2012 and July 2015, we conducted a prospective cross-sectional two centre study using cerebral magnetic resonance imaging (MRI) and neuro-developmental outcome assessed by the Bayley-III. Forty-seven children (31 male) were evaluated at a mean age of 25.9 ± 3.4 months with hypoplastic left heart syndrome (25) or other single ventricle (22). Cerebral MRI was abnormal in 17 patients (36.2%) including liquor space enlargements (10), small grey (9) and minimal white (5) matter injuries. Eight of 17 individuals had combined lesions. Median (range) cognitive composite score (CCS) (100, 65-120) and motor composite score (MCS) (97, 55-124) were comparable to the reference data, while language composite score (LCS) (97, 68-124) was significantly lower ( P  = 0.040). Liquor space enlargement was associated with poorer performance on all Bayley-III subscores (CCS: P  = 0.02; LCS: P  = 0.002; MCS: P  = 0.013). The number of re-operations [odds ratio (OR) 2.2, 95% confidence interval (CI) 1.1-4.3] ( P  = 0.03) and re-interventions (OR 2.1, 95% CI 1.1-3.8) ( P  = 0.03) was associated with a higher rate of overall MRI abnormalities. Cerebral MRI abnormalities occur in more than one third of children with single ventricle, while the neuro-developmental status is less severely affected before Fontan procedure. Liquor space enlargement is the predominant MRI finding associated with poorer neuro-developmental status, warranting further studies to determine aetiology and further evolution until school-age. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  10. Removal of Muscle Artifacts from Single-Channel EEG Based on Ensemble Empirical Mode Decomposition and Multiset Canonical Correlation Analysis

    Directory of Open Access Journals (Sweden)

    Xun Chen

    2014-01-01

    Full Text Available Electroencephalogram (EEG recordings are often contaminated with muscle artifacts. This disturbing muscular activity strongly affects the visual analysis of EEG and impairs the results of EEG signal processing such as brain connectivity analysis. If multichannel EEG recordings are available, then there exist a considerable range of methods which can remove or to some extent suppress the distorting effect of such artifacts. Yet to our knowledge, there is no existing means to remove muscle artifacts from single-channel EEG recordings. Moreover, considering the recently increasing need for biomedical signal processing in ambulatory situations, it is crucially important to develop single-channel techniques. In this work, we propose a simple, yet effective method to achieve the muscle artifact removal from single-channel EEG, by combining ensemble empirical mode decomposition (EEMD with multiset canonical correlation analysis (MCCA. We demonstrate the performance of the proposed method through numerical simulations and application to real EEG recordings contaminated with muscle artifacts. The proposed method can successfully remove muscle artifacts without altering the recorded underlying EEG activity. It is a promising tool for real-world biomedical signal processing applications.

  11. Neuromuscular organization of avian flight muscle: architecture of single muscle fibres in muscle units of the pectoralis (pars thoracicus) of pigeon (Columba livia)

    Science.gov (United States)

    Sokoloff, A. J.

    1999-01-01

    The M. pectoralis (pars thoracicus) of pigeons (Columba livia) is comprised of short muscle fibres that do not extend from muscle origin to insertion but overlap 'in-series'. Individual pectoralis motor units are limited in territory to a portion of muscle length and are comprised of either fast twitch, oxidative and glycolytic fibres (FOG) or fast twitch and glycolytic fibres (FG). FOG fibres make up 88 to 90% of the total muscle population and have a mean diameter one-half of that of the relatively large FG fibres. Here we report on the organization of individual fibres identified in six muscle units depleted of glycogen, three comprised of FOG fibres and three comprised of FG fibres. For each motor unit, fibre counts revealed unequal numbers of depleted fibres in different unit cross-sections. We traced individual fibres in one unit comprised of FOG fibres and a second comprised of FG fibres. Six fibres from a FOG unit (total length 15.45 mm) ranged from 10.11 to 11.82 mm in length and averaged (± s.d.) 10.74 ± 0.79 mm. All originated bluntly (en mass) from a fascicle near the proximal end of the muscle unit and all terminated intramuscularly. Five of these ended in a taper and one ended bluntly. Fibres coursed on average for 70% of the muscle unit length. Six fibres from a FG unit (total length 34.76 mm) ranged from 8.97 to 18.38 mm in length and averaged 15.32 ± 3.75 mm. All originated bluntly and terminated intramuscularly; one of these ended in a taper and five ended bluntly. Fibres coursed on average for 44% of the muscle unit length. Because fibres of individual muscle units do not extend the whole muscle unit territory, the effective cross-sectional area changes along the motor unit length. These non-uniformities in the distribution of fibres within a muscle unit emphasize that the functional interactions within and between motor units are complex.

  12. Cyclic AMP-receptor proteins in heart muscle of rats flown on Cosmos 1887

    Science.gov (United States)

    Mednieks, Maija I.; Popova, Irina A.; Grindeland, Richard E.

    1991-01-01

    The cellular compartmentalization of the cyclic AMP-receptor proteins in heart ventricular tissue obtained from rats flown on the Cosmos 1887 is determined. Photoaffinity labeling of soluble and particular cell fractions with a (32P)-8-azido analog of cyclic AMP is followed by electrophoretic separation of the proteins and by autoradiographic identification of the labeled isoforms of cAPK R subunits. It is shown that RII in the particulate subcellular fraction was significantly decreased in heart cells from rats in the flight group when compared to controls. Protein banding patterns in both the cytoplasmic fraction and in a fraction enriched in chromatin-bound proteins exhibited some variability in tissues of individual animals, but showed no changes that could be directly attributed to flight conditions. No significant change was apparent in the distribution of RI or RII cyclic AMP binding in the soluble fractions. It is inferred that the cardiac cell integrity or its protein content is not compromised under flight conditions.

  13. An advanced chronic heart failure day care service: a 5 year single-center experience.

    Science.gov (United States)

    Freimark, Dov; Arad, Michael; Matetzky, Shlomi; DeNeen, Isabell; Gershovitz, Liron; Morag, Nira Koren; Hochberg, Naomi; Makmal, Yafit; Shechter, Michael

    2009-07-01

    Chronic heart failure is associated with excessive hospitalizations and poor prognosis. To summarize the 5 year experience of a single-center CHF day care service, detect the cardiovascular and non-cardiovascular events, and evaluate the safety of the treatments provided. We retrospectively studied all patients admitted to the CHF day care service of the Sheba Medical Center between September 2000 and September 2005. Advanced (New York Heart Association class III-IV) CHF patients (n = 190), mean age 65 +/- 12 years and left ventricular ejection fraction 25 +/- 11%, were treated for 6 hourly biweekly visits; 77% had ischemic and 23% had nonischemic cardiomyopathy. Treatment included: intravenous diuretic combinations (91%), intermittent low dose (< or = 5 microg/kg/min) dobutamine (87%), low dose (< or = 3 microg/kg/min) dopamine (38%), intravenous iron preparation and/or blood (47%), and intravenous nitropruside (36%). Follow-up of at least 1 year from initiation of therapy was completed in 158 of 190 patients (83%). Forty-six (29.3%) died: 23% due to CHF exacerbation, 5.7% from infection, 4.4% from sudden cardiac death, 3.8% from malignancy, 2.5% from malignant arrhythmias, 1.9% from renal failure, 1.3% from stroke, and 0.6% from myocardial infarction. There were only 0.68 rehospitalizations/patient/year; the most frequent cause being CHF exacerbation (16.5%). Our study demonstrates the safety and potential benefits of a supportive day care service for advanced CHF patients. Multidrug intravenous treatment, accompanied by monitoring of electrolytes, hemoglobin and cardiac rhythm, along with education and psychological support, appear to reduce morbidity in advanced CHF patients and may have contributed to the lower than expected mortality/ hospitalization rate.

  14. The use of the Berlin Heart EXCOR in patients with functional single ventricle.

    Science.gov (United States)

    Weinstein, Samuel; Bello, Ricardo; Pizarro, Christian; Fynn-Thompson, Francis; Kirklin, James; Guleserian, Kristine; Woods, Ronald; Tjossem, Christine; Kroslowitz, Robert; Friedmann, Patricia; Jaquiss, Robert

    2014-02-01

    The frequency and successful use of pediatric ventricular assist devices (VADs) as a bridge to cardiac transplantation have been steadily increasing since 2003, but the experience in patients with complex congenital heart disease has not been well described. Using a large prospectively collected dataset of children supported with the Berlin Heart EXCOR VAD, we have reviewed the experience in children with single ventricular anatomy or physiology (SV), and compared the results with those supported with biventricular circulation (BV) over the same time period. The EXCOR Investigational Device Exemption study database was retrospectively reviewed. VAD implants under the primary cohort and compassionate use cohort between May 2007 and December 2011 were included in this review. Twenty-six of 281 patients supported with a VAD were SV. The most common diagnosis was hypoplastic left heart syndrome (15 of 26). Nine patients were supported after neonatal palliative surgery (Blalock-Taussig shunt or Sano), 12 after a superior cavopulmonary connection (SCPC), and 5 after total cavopulmonary connection (TCPC). Two patients received biventricular assist devices, 1 after stage I surgery and 1 after stage II. SV patients were supported for a median time of 10.5 days (range, 1-363 days) versus 39 days (range, 0-435 days) for BV (P = .01). The ability to be bridged to transplant or recovery in SV patients is lower than for BV patients (11 of 26 [42.3%] vs 185 of 255 [72.5%]; P = .001). Three of 5 patients with TCPC were successfully bridged to transplant and were supported with 1 VAD. Seven of 12 patients with SCPC were bridged to transplant, and only 1 of 9 patients supported after a stage I procedure survived. The EXCOR Pediatric VAD can provide a bridge to transplant for children with SV anatomy or physiology, albeit less successfully than in children with BV. In this small series, results are better in patients with SCPC and TCPC. VAD support for patients with shunted sources

  15. Fetal Tendinous Connection Between the Tensor Tympani and Tensor Veli Palatini Muscles: A Single Digastric Muscle Acting for Morphogenesis of the Cranial Base.

    Science.gov (United States)

    Rodríguez-Vázquez, José Francisco; Sakiyama, Koji; Abe, Hiroshi; Amano, Osamu; Murakami, Gen

    2016-04-01

    Some researchers contend that in adults the tensor tympani muscle (TT) connects with the tensor veli palatini muscle (TVP) by an intermediate tendon, in disagreement with the other researchers. To resolve this controversy, we examined serial sections of 50 human embryos and fetuses at 6-17 weeks of development. At 6 weeks, in the first pharyngeal arch, a mesenchymal connection was found first to divide a single anlage into the TT and TVP. At and after 7 weeks, the TT was connected continuously with the TVP by a definite tendinous tissue mediolaterally crossing the pharyngotympanic tube. At 11 weeks another fascia was visible covering the cranial and lateral sides of the tube. This "gonial fascia" had two thickened borders: the superior one corresponded to a part of the connecting tendon between the TT and TVP; the inferior one was a fibrous band ending at the os goniale near the lateral end of the TVP. In association with the gonial fascia, the fetal TT and TVP seemed to provide a functional complex. The TT-TVP complex might first help elevate the palatal shelves in association with the developing tongue. Next, the tubal passage, maintained by contraction of the muscle complex, seems to facilitate the removal of loose mesenchymal tissues from the tympanic cavity. Third, the muscle complex most likely determined the final morphology of the pterygoid process. Consequently, despite the controversial morphologies in adults, the TT and TVP seemed to make a single digastric muscle acting for the morphogenesis of the cranial base. © 2016 Wiley Periodicals, Inc.

  16. Estimation of thigh muscle cross-sectional area by single- and multifrequency segmental bioelectrical impedance analysis in the elderly.

    Science.gov (United States)

    Yamada, Yosuke; Ikenaga, Masahiro; Takeda, Noriko; Morimura, Kazuhiro; Miyoshi, Nobuyuki; Kiyonaga, Akira; Kimura, Misaka; Higaki, Yasuki; Tanaka, Hiroaki

    2014-01-15

    Bioelectrical impedance analysis (BIA) has been used to estimate skeletal muscle mass, but its application in the elderly is not optimal. The accuracy of BIA may be influenced by the expansion of extracellular water (ECW) relative to muscle mass with aging. Multifrequency BIA (MFBIA) can evaluate the distribution between ECW and intracellular water (ICW), and thus may be superior to single-frequency BIA (SFBIA) to estimate muscle mass in the elderly. A total of 58 elderly participants aged 65-85 years were recruited. Muscle cross-sectional area (CSA) was obtained from computed tomography scans at the mid-thigh. Segmental SFBIA and MFBIA were measured for the upper legs. An index of the ratio of ECW and ICW was calculated using MFBIA. The correlation between muscle CSA and SFBIA was moderate (r = 0.68), but strong between muscle CSA and MFBIA (r = 0.85). ECW/ICW index was significantly and positively correlated with age (P < 0.001). SFBIA tends to significantly overestimate muscle CSA in subjects who had relative expansion of ECW in the thigh segment (P < 0.001). This trend was not observed for MFBIA (P = 0.42). Relative expansion of ECW was observed in older participants. The relative expansion of ECW affects the validity of traditional SFBIA, which is lowered when estimating muscle CSA in the elderly. By contrast, MFBIA was not affected by water distribution in thigh segments, thus rendering the validity of MFBIA for estimating thigh muscle CSA higher than SFBIA in the elderly.

  17. Subcellular distribution of glycogen and decreased tetanic Ca2+ in fatigued single intact mouse muscle fibres

    Science.gov (United States)

    Nielsen, Joachim; Cheng, Arthur J; Ørtenblad, Niels; Westerblad, Håkan

    2014-01-01

    In skeletal muscle fibres, glycogen has been shown to be stored at different subcellular locations: (i) between the myofibrils (intermyofibrillar); (ii) within the myofibrils (intramyofibrillar); and (iii) subsarcolemmal. Of these, intramyofibrillar glycogen has been implied as a critical regulator of sarcoplasmic reticulum Ca2+ release. The aim of the present study was to test directly how the decrease in cytoplasmic free Ca2+ ([Ca2+]i) during repeated tetanic contractions relates to the subcellular glycogen distribution. Single fibres of mouse flexor digitorum brevis muscles were fatigued with 70 Hz, 350 ms tetani given at 2 s (high-intensity fatigue, HIF) or 10 s (low-intensity fatigue, LIF) intervals, while force and [Ca2+]i were measured. Stimulation continued until force decreased to 30% of its initial value. Fibres were then prepared for analyses of subcellular glycogen distribution by transmission electron microscopy. At fatigue, tetanic [Ca2+]i was reduced to 70 ± 4% and 54 ± 4% of the initial in HIF (P glycogen content was 60–75% lower than in rested control fibres (P glycogen was similar to control. Individual fibres showed a good correlation between the fatigue-induced decrease in tetanic [Ca2+]i and the reduction in intermyofibrillar (P = 0.051) and intramyofibrillar (P = 0.0008) glycogen. In conclusion, the fatigue-induced decrease in tetanic [Ca2+]i, and hence force, is accompanied by major reductions in inter- and intramyofibrillar glycogen. The stronger correlation between decreased tetanic [Ca2+]i and reduced intramyofibrillar glycogen implies that sarcoplasmic reticulum Ca2+ release critically depends on energy supply from the intramyofibrillar glycogen pool. PMID:24591577

  18. Subcellular distribution of glycogen and decreased tetanic Ca2+ in fatigued single intact mouse muscle fibres.

    Science.gov (United States)

    Nielsen, Joachim; Cheng, Arthur J; Ørtenblad, Niels; Westerblad, Hakan

    2014-05-01

    In skeletal muscle fibres, glycogen has been shown to be stored at different subcellular locations: (i) between the myofibrils (intermyofibrillar); (ii) within the myofibrils (intramyofibrillar); and (iii) subsarcolemmal. Of these, intramyofibrillar glycogen has been implied as a critical regulator of sarcoplasmic reticulum Ca(2+) release. The aim of the present study was to test directly how the decrease in cytoplasmic free Ca(2+) ([Ca(2+)]i) during repeated tetanic contractions relates to the subcellular glycogen distribution. Single fibres of mouse flexor digitorum brevis muscles were fatigued with 70 Hz, 350 ms tetani given at 2 s (high-intensity fatigue, HIF) or 10 s (low-intensity fatigue, LIF) intervals, while force and [Ca(2+)]i were measured. Stimulation continued until force decreased to 30% of its initial value. Fibres were then prepared for analyses of subcellular glycogen distribution by transmission electron microscopy. At fatigue, tetanic [Ca(2+)]i was reduced to 70 ± 4% and 54 ± 4% of the initial in HIF (P glycogen content was 60-75% lower than in rested control fibres (P glycogen was similar to control. Individual fibres showed a good correlation between the fatigue-induced decrease in tetanic [Ca(2+)]i and the reduction in intermyofibrillar (P = 0.051) and intramyofibrillar (P = 0.0008) glycogen. In conclusion, the fatigue-induced decrease in tetanic [Ca(2+)]i, and hence force, is accompanied by major reductions in inter- and intramyofibrillar glycogen. The stronger correlation between decreased tetanic [Ca(2+)]i and reduced intramyofibrillar glycogen implies that sarcoplasmic reticulum Ca(2+) release critically depends on energy supply from the intramyofibrillar glycogen pool.

  19. Heat stress in the heart and muscle of the Antarctic fishes Notothenia rossii and Notothenia coriiceps: Carbohydrate metabolism and antioxidant defence.

    Science.gov (United States)

    Souza, Maria Rosa Dmengeon Pedreiro de; Herrerias, Tatiana; Zaleski, Tania; Forgati, Mariana; Kandalski, Priscila Krebsbach; Machado, Cintia; Silva, Dilza Trevisan; Piechnik, Cláudio Adriano; Moura, Maurício Osvaldo; Donatti, Lucélia

    2018-03-01

    Carbohydrate metabolism and the antioxidant defence system of heart and muscle of the Antarctic notothenioids Notothenia rossii and Notothenia coriiceps were evaluated in response to heat stress (8 °C) over 144 h. N. rossii heart exhibited decreased glycolysis and aerobic metabolism after up to 12 h of exposure to 8 °C, and anaerobiosis was inhibited within 24 h. However, these pathways were stimulated after 72 h at 8 °C. The consumption of glucose-6-phosphate, derived from hexokinase (HK), by glucose-6-phosphate dehydrogenase (G6PDH) decreased in N. rossii heart within 6 h at 8 °C, with a subsequent increase at 72 h. In N. rossii muscle at 8 °C, glycolysis was stimulated within 2 h by an increase in pyruvate kinase (PK), and aerobic metabolism was stimulated at 144 h, together with anaerobiosis. In N. coriiceps heart at 8 °C, glucose break down by HK decreased within 2 h and subsequently increased at 12 and 24 h. Increased glucose-6-phosphate consumption by G6PDH occurred within 6 h at 8 °C. In N. coriiceps muscle at 8 °C, glycolysis was stimulated at 2 and 6 h, with subsequent inhibition within 24 h, as indicated by HK activity. Aerobic metabolism was inhibited at 72 and 144 h at 8 °C through the inhibition of citrate synthase (CS). Heat stress caused responses were only occasional and transient in antioxidant defence system of both species in the heart and muscle, leading to increased glutathione (GSH) and decreased levels of lipoperoxidation in the heart of both species. The results obtained in this study in the heart and muscles indicate that under heat stress at 8 °C, N. rossii is more responsive than N. coriiceps with respect to carbohydrate metabolism. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  20. l-arginine modulates inflammation and muscle regulatory genes after a single session of resistance exercise in rats.

    Science.gov (United States)

    Morais, S R L; Brito, V G B; Mello, W G; Oliveira, S H P

    2018-02-01

    We investigated the skeletal muscle adaptation to l-arginine supplementation prior to a single session of resistance exercise (RE) during the early phase of muscle repair. Wistar rats were randomly assigned into non-exercised (Control), RE plus vehicle (RE); RE plus l-arginine (RE+L-arg) and RE plus aminoguanidine (RE+AG) groups. Animals received four doses of either vehicle (0.9% NaCl), l-arg (1 g/b.w.), or AG (iNOS inhibitor) (50 mg/b.w.). The animals performed a single RE session until the concentric failure (ladder climbing; 80% overload) and the skeletal muscles were harvested at 0, 8, 24, and 48 hours post-RE. The RE resulted in increased neutrophil infiltrate (24 hours post-RE) (3621 vs 11852; Pl-arginine supplementation attenuates neutrophil infiltration (5622; Pl-arginine supplementation seems to attenuate the resolution of RE-induced muscle inflammation and up-regulates MyoD expression during the early phase of muscle repair. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Highlights from the Functional Single Nucleotide Polymorphisms Associated with Human Muscle Size and Strength or FAMuSS Study

    Directory of Open Access Journals (Sweden)

    Linda S. Pescatello

    2013-01-01

    Full Text Available The purpose of the Functional Single Nucleotide Polymorphisms Associated with Human Muscle Size and Strength study or FAMuSS was to identify genetic factors that dictated the response of health-related fitness phenotypes to resistance exercise training (RT. The phenotypes examined were baseline muscle strength and muscle, fat, and bone volume and their response to RT. FAMuSS participants were 1300 young (24 years, healthy men (42% and women (58% that were primarily of European-American descent. They were genotyped for ~500 polymorphisms and completed the Paffenbarger Physical Activity Questionnaire to assess energy expenditure and time spent in light, moderate, and vigorous intensity habitual physical activity and sitting. Subjects then performed a 12-week progressive, unilateral RT program of the nondominant arm with the dominant arm used as a comparison. Before and after RT, muscle strength was measured with the maximum voluntary contraction and one repetition maximum, while MRI measured muscle, fat, and bone volume. We will discuss the history of how FAMuSS originated, provide a brief overview of the FAMuSS methods, and summarize our major findings regarding genotype associations with muscle strength and size, body composition, cardiometabolic biomarkers, and physical activity.

  2. Muscle and liver-specific alterations in lipid and acylcarnitine metabolism after a single bout of exercise in mice.

    Science.gov (United States)

    Hoene, Miriam; Li, Jia; Li, Yanjie; Runge, Heike; Zhao, Xinjie; Häring, Hans-Ulrich; Lehmann, Rainer; Xu, Guowang; Weigert, Cora

    2016-02-26

    Intracellular lipid pools are highly dynamic and tissue-specific. Physical exercise is a strong physiologic modulator of lipid metabolism, but most studies focus on changes induced by long-term training. To assess the acute effects of endurance exercise, mice were subjected to one hour of treadmill running, and (13)C16-palmitate was applied to trace fatty acid incorporation in soleus and gastrocnemius muscle and liver. The amounts of carnitine, FFA, lysophospholipids and diacylglycerol and the post-exercise increase in acetylcarnitine were pronouncedly higher in soleus than in gastrocnemius. In the liver, exercise increased the content of lysophospholipids, plasmalogens and carnitine as well as transcript levels of the carnitine transporter. (13)C16-palmitate was detectable in several lipid and acylcarnitine species, with pronounced levels of tracer-derived palmitoylcarnitine in both muscles and a strikingly high incorporation into triacylglycerol and phosphatidylcholine in the liver. These data illustrate the high lipid storing activity of the liver immediately after exercise whereas in muscle, fatty acids are directed towards oxidation. The observed muscle-specific differences accentuate the need for single-muscle analyses as well as careful consideration of the particular muscle employed when studying lipid metabolism in mice. In addition, our results reveal that lysophospholipids and plasmalogens, potential lipid signalling molecules, are acutely regulated by physical exercise.

  3. The total body mass of fatty acid ethyl esters in skeletal muscles following ethanol exposure greatly exceeds that found in the liver and the heart.

    Science.gov (United States)

    Salem, Raneem O; Laposata, Michael; Rajendram, Rajkumar; Cluette-Brown, Joanne E; Preedy, Victor R

    2006-01-01

    Skeletal muscle appears to be susceptible to chronic and acute excess alcohol intake, giving rise to alcoholic myopathy, a common disease among alcoholics. Fatty acid ethyl esters (FAEE), non-oxidative metabolites of ethanol, have been shown to be toxic to cells in vitro and in vivo. We hypothesized that accumulation of FAEE in skeletal muscle could contribute to the development of alcoholic myopathy. Male wistar rats were treated either with 75 mmol ethanol/kg body weight or saline, in the fed state or starved for 1 or 2 days before administration. Rats were thus divided into the following groups: fed-saline (n = 8); fed-ethanol (n = 8); starved 1 day, saline (n = 8); starved 1 day, ethanol (n = 9); starved 2 days, saline (n = 7); and starved 2 days, ethanol (n = 8). At the end of the incubation, skeletal muscles (abdominal and gastrocnemius), liver, and heart were isolated and processed for FAEE isolation and analysis by gas chromatography-mass spectrometry (GC-MS). Total mass of FAEE in the muscles was much greater than that found in the liver and the heart. In general, the animals that were fasted for 1 day and received ethanol had the highest FAEE levels among the three groups of animals. The major ethyl ester species in all cases were ethyl 16:0, ethyl 18:0, ethyl 18:1 n-9, and ethyl 18:2 n-6. Ethyl 20:4 n-6 and ethyl 22:6 n-3 were also present, except in the fasted 1-day group, where ethyl 22:6 disappeared, though it reappeared in the fasted 2-day group. These findings demonstrate that skeletal muscles contain high levels of FAEE that are synthesized in the body after ethanol exposure. The concentration of FAEE in skeletal muscle in this study was very similar to FAEE concentration in the liver. This differs from previous studies suggesting a low concentration of skeletal muscle FAEE with ethanol exposure.

  4. Elevation in heat shock protein 72 mRNA following contractions in isolated single skeletal muscle fibers.

    Science.gov (United States)

    Stary, Creed M; Walsh, Brandon J; Knapp, Amy E; Brafman, David; Hogan, Michael C

    2008-08-01

    The purpose of the present study was 1) to develop a stable model for measuring contraction-induced elevations in mRNA in single skeletal muscle fibers and 2) to utilize this model to investigate the response of heat shock protein 72 (HSP72) mRNA following an acute bout of fatiguing contractions. Living, intact skeletal muscle fibers were microdissected from lumbrical muscle of Xenopus laevis and either electrically stimulated for 15 min of tetanic contractions (EX; n=26) or not stimulated to contract (REST; n=14). The relative mean developed tension of EX fibers decreased to 29+/-7% of initial peak tension at the stimulation end point. Following treatment, individual fibers were allowed to recover for 1 (n=9), 2 (n=8), or 4 h (n=9) prior to isolation of total cellular mRNA. HSP72, HSP60, and cardiac alpha-actin mRNA content were then assessed in individual fibers using quantitative PCR detection. Relative HSP72 mRNA content was significantly (Pelevated at the 2-h postcontraction time point relative to REST fibers when normalized to either HSP60 (18.5+/-7.5-fold) or cardiac alpha-actin (14.7+/-4.3-fold), although not at the 1- or 4-h time points. These data indicate that 1) extraction of RNA followed by relative quantification of mRNA of select genes in isolated single skeletal muscle fibers can be reliably performed, 2) HSP60 and cardiac alpha-actin are suitable endogenous normalizing genes in skeletal muscle following contractions, and 3) a significantly elevated content of HSP72 mRNA is detectable in skeletal muscle 2 h after a single bout of fatiguing contractions, despite minimal temperature changes and without influence from extracellular sources.

  5. Sleep Apnoea Detection in Single Channel ECGs by Analyzing Heart Rate Dynamics

    National Research Council Canada - National Science Library

    Zywietz, C

    2001-01-01

    .... Our analysis is based on spectral components of heart rate variability. Frequency analysis was performed using Fourier and wavelet transformation with appropriate application of the Hilbert transform...

  6. Single-cell sequencing analysis characterizes common and cell-lineage-specific mutations in a muscle-invasive bladder cancer

    DEFF Research Database (Denmark)

    Li, Yingrui; Xu, Xun; Song, Luting

    2012-01-01

    sequencing of 66 individual tumor cells from a muscle-invasive bladder transitional cell carcinoma (TCC). Analyses of the somatic mutant allele frequency spectrum and clonal structure revealed that the tumor cells were derived from a single ancestral cell, but that subsequent evolution occurred, leading...... to two distinct tumor cell subpopulations. By analyzing recurrently mutant genes in an additional cohort of 99 TCC tumors, we identified genes that might play roles in the maintenance of the ancestral clone and in the muscle-invasive capability of subclones of this bladder cancer, respectively...

  7. [Parameters of cardiac muscle repolarization on the electrocardiogram when changing anatomical and electric position of the heart].

    Science.gov (United States)

    Chaĭkovskiĭ, I A; Baum, O V; Popov, L A; Voloshin, V I; Budnik, N N; Frolov, Iu A; Kovalenko, A S

    2014-01-01

    While discussing the diagnostic value of the single channel electrocardiogram a set of theoretical considerations emerges inevitably, one of the most important among them is the question about dependence of the electrocardiogram parameters from the direction of electrical axis of heart. In other words, changes in what of electrocardiogram parameters are in fact liable to reflect pathological processes in myocardium, and what ones are determined by extracardiac factors, primarily by anatomic characteristics of patients. It is arguable that while analyzing electrocardiogram it is necessary to orient to such physiologically based informative indexes as ST segment displacement. Also, symmetry of the T wave shape is an important parameter which is independent of patients anatomic features. The results obtained are of interest for theoretical and applied aspects of the biophysics of the cardiac electric field.

  8. Single motor unit firing behavior in the right trapezius muscle during rapid movement of right or left index finger

    DEFF Research Database (Denmark)

    Søgaard, Karen; Olsen, Henrik B; Blangsted, Anne K

    2014-01-01

    of a general multi joint motor program, while a generally increased and continuous firing rate would support the attention related muscle activation. METHOD: Twelve healthy female subjects were seated at a computer work place with elbows and forearms supported. Ten double clicks (DC) were performed with right......BACKGROUND: Computer work is associated with low level sustained activity in the trapezius muscle that may cause development of trapezius myalgia. Such a low level activity may be attention related or alternatively, be part of a general multi joint motor program providing stabilization...... of the shoulder joint as a biomechanical prerequisite for precise finger manipulation. This study examines single motor unit (MU) firing pattern in the right trapezius muscle during fast movements of ipsilateral or contralateral index finger. A modulation of the MU firing rate would support the existence...

  9. Effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults

    Directory of Open Access Journals (Sweden)

    Wehrle Anja

    2010-11-01

    Full Text Available Abstract Background Muscle fatigue and dual-task walking (e.g., concurrent performance of a cognitive interference (CI while walking represent major fall risk factors in young and older adults. Thus, the objectives of this study were to examine the effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults and to determine the impact of muscle fatigue on dual-task costs while walking. Methods Thirty-two young (24.3 ± 1.4 yrs, n = 16 and old (71.9 ± 5.5 yrs, n = 16 healthy active adults participated in this study. Fatigue of the knee extensors/flexors was induced by isokinetic contractions. Subjects were tested pre and post fatigue, as well as after a 5 min rest. Tests included the assessment of gait velocity, stride length, and stride length variability during single (walking, and dual (CI+walking task walking on an instrumented walkway. Dual-task costs while walking were additionally computed. Results Fatigue resulted in significant decreases in single-task gait velocity and stride length in young adults, and in significant increases in dual-task gait velocity and stride length in older adults. Further, muscle fatigue did not affect dual-task costs during walking in young and older adults. Performance in the CI-task was improved in both age groups post-fatigue. Conclusions Strategic and/or physiologic rationale may account for the observed differences in young and older adults. In terms of strategic rationale, older adults may walk faster with longer strides in order to overcome the feeling of fatigue-induced physical discomfort as quickly as possible. Alternatively, older adults may have learned how to compensate for age-related and/or fatigue-induced muscle deficits during walking by increasing muscle power of synergistic muscle groups (e.g., hip flexors. Further, a practice and/or learning effect may have occurred from pre to post testing. Physiologic rationale may comprise motor unit

  10. Ten-year survival and prognostic markers in one thousand patients with advanced heart failure. A single-centre analysis.

    Science.gov (United States)

    Lesny, Peter; Luknar, Milan; Matejka, Martin; Varga, Ivan; Solik, Peter; Wimmerova, Sona; Goncalvesova, Eva

    2016-06-01

    Patients with advanced heart failure (HF) represent a pool of candidates for heart transplantation and long-term mechanical circulatory support devices. The aim of our study was to determine simple and reliable markers of one-year mortality for selection of the most suitable patients for heart replacement therapy. One thousand consecutive patients with HF (mean age 49 ± 10.9 years; 86.8% males) referred to a single tertiary centre from January 1998 to January 2010 in order to assess the indication for heart transplantation were enrolled. Kaplan-Meier survival analysis was performed. Independent mortality predictors were established using logistic regression analysis. The mean follow-up was 4.3 ± 2.7 years (range 1-12 years). Cumulative survival was as follows: 1-year survival 83%, 3-year 63%, 5-year 50%, 7-year 39%, and 10-year 23%. Independent predictors of 1-year mortality included coronary artery disease, left ventricular diastolic diameter >79 mm, plasma sodium 240 mg/day. Short-term prognosis of HF patient can be estimated based on simple parameters. Patients with signs of poor prognosis should be referred to tertiary centres to be considered for heart replacement therapy.

  11. BUILDING A BETTER GLUTEAL BRIDGE: ELECTROMYOGRAPHIC ANALYSIS OF HIP MUSCLE ACTIVITY DURING MODIFIED SINGLE-LEG BRIDGES

    Science.gov (United States)

    Edwards, Michael; Haverkamp, Ryan; Martin, Lani; Porter, Kambry; Thach, Kailey; Sack, Richard J.; Hakansson, Nils A.

    2017-01-01

    Background Gluteal strength plays a role in injury prevention, normal gait patterns, eliminating pain, and enhancing athletic performance. Research shows high gluteal muscle activity during a single-leg bridge compared to other gluteal strengthening exercises; however, prior studies have primarily measured muscle activity with the active lower extremity starting in 90 ° of knee flexion with an extended contralateral knee. This standard position has caused reports of hamstring cramping, which may impede optimal gluteal strengthening. Hypothesis/Purpose The purpose of this study was to determine which modified position for the single-leg bridge is best for preferentially activating the gluteus maximus and medius. Study Design Cross-Sectional Methods Twenty-eight healthy males and females aged 18-30 years were tested in five different, randomized single-leg bridge positions. Electromyography (EMG) electrodes were placed on subjects’ gluteus maximus, gluteus medius, rectus femoris, and biceps femoris of their bridge leg (i.e., dominant or kicking leg), as well as the rectus femoris of their contralateral leg. Subjects performed a maximal voluntary isometric contraction (MVIC) for each tested muscle prior to performing five different bridge positions in randomized order. All bridge EMG data were normalized to the corresponding muscle MVIC data. Results A modified bridge position with the knee of the bridge leg flexed to 135 ° versus the traditional 90 ° of knee flexion demonstrated preferential activation of the gluteus maximus and gluteus medius compared to the traditional single-leg bridge. Hamstring activation significantly decreased (p gluteus maximus and medius, respectively). Conclusion Modifying the traditional single-leg bridge by flexing the active knee to 135 ° instead of 90 ° minimizes hamstring activity while maintaining high levels of gluteal activation, effectively building a bridge better suited for preferential gluteal activation

  12. Oxygen saturation and heart rate monitoring during a single session of early rehabilitation after cardiac surgery.

    Science.gov (United States)

    Sala, Vittorio; Petrucci, Lucia; Monteleone, Serena; Dall'Angelo, Anna; Miracca, Stefania; Conte, Teresa; Carlisi, Ettore; Ricotti, Susanna; D'Armini, Andrea M; Dalla Toffola, Elena

    2016-02-01

    Early rehabilitation after cardiac surgery aims to prevent immobilization, to reduce the effects of surgery on the respiratory function and to facilitate the recovery of autonomy in the activities of daily living (ADL), after discharge. Nevertheless the optimal perioperative physical therapy care for patients undergoing cardiac surgery is not well established. Moreover, most of the studies monitored peripheral oxygen saturation (SpO2) and heart rate (HR) during surgery or focused only on their recovery after rehabilitation and not on their pathways during a session of exercises. To monitor peripheral oxygen saturation and HR before, during and at the end of a single session of early rehabilitation after cardiac surgery, so testing our protocol's safety. A case series. Department of Cardiothoracic Surgery, inpatients. Forty-eight consecutive inpatients (35 M), mean age 61 years, with cardiovascular disease (CVD), who underwent cardiac surgery. We monitored SpO2%, HR, systemic blood pressure (BP), pain in the thoracic wound (VAS) and rate of perceived exertion (RPE) during the rehabilitation session after weaning from oxygen therapy. During all phases mean SpO2 was 94% (±1.8) and mean HR was 85 bpm (±13.3). Number of desaturation events were 14 in total and mean of % of time with SpO2<90% was 3 (±6.5) during all the rehabilitative session. Moreover, mean BP after reaching the sitting position was 124.7 (±11.9)/78.6 (±8.4) and after ambulation was 131.5 (±11.5)/82.9 (±7.3). The monitoring peripheral oxygen saturation and HR during and not only before and at the end of a standardized early rehabilitation session helped us to ensure the safety of our protocol. Because of its feasibility, safety and reproducibility our rehabilitation treatment has been applied to different types of surgical inpatients in order to limit the negative consequences of immobilization.

  13. The effect of calf stretching box on stretching calf muscle compliance: a prospective, randomized single-blinded controlled trial.

    Science.gov (United States)

    Chadchavalpanichaya, Navaporn; Srisawasdi, Gulapar; Suwannakin, Atchara

    2010-12-01

    To study the effect of calf stretching box usage in increasing the compliance of performing calf stretching exercise as compared to the conventional exercise method. To study the effect of calf stretching box usage in decreasing the calf muscle tightness and complications as compared to the conventional exercise method. Eighty patients older than 45 years old with calf muscles tightness were enrolled in a prospective, randomized single-blinded controlled trial at the out-patient Rehabilitation medicine clinic, Siriraj Hospital, Bangkok Thailand between April and August 2009. Patients were randomized into two groups, the study group (stretching by using calf stretching box) and the control group (stretching by the conventional exercise method). Patients in both groups were asked to hold the stretch for at least 1 minute and to perform the stretching program at least two times per day, every day for two weeks. Furthermore, they were asked to record the real frequency and duration of their exercise and complications in a logbook every day. Thirty-eight patients in each group completed the study. The baseline characteristics of the patients in both groups were similar. The study group had higher frequency and longer duration of performing calf stretching exercise than the control group. They also reported more decrease of calf muscle tightness with less pain complication (shoulder pain, knee pain, low back pain, and calf muscle pain) than the control group (p calf muscle and degree of ankle range of motion between the two groups. Stretching calf muscle with calf stretching box can increase compliance, decrease calf muscle tightness and decrease complications when compared with the conventional exercise method.

  14. Effects of inactivity on human muscle glutathione synthesis by a double-tracer and single-biopsy approach.

    Science.gov (United States)

    Agostini, Francesco; Dalla Libera, Luciano; Rittweger, Jörn; Mazzucco, Sara; Jurdana, Mihaela; Mekjavic, Igor B; Pisot, Rado; Gorza, Luisa; Narici, Marco; Biolo, Gianni

    2010-12-15

    Oxidative stress is often associated to inactivity-mediated skeletal muscle atrophy. Glutathione is one of the major antioxidant systems stimulated, both at muscular and systemic level, by activation of oxidative processes. We measured changes in glutathione availability, oxidative stress induction and the extent of atrophy mediated by 35 days of experimental bed rest in vastus lateralis muscle of healthy human volunteers. To assess muscle glutathione synthesis, we applied a novel single-biopsy and double-tracer ([(2)H(2)]glycine and [(15)N]glycine) approach based on evaluation of steady-state precursor incorporation in product. The correlations between the traditional (multiple-samples, one-tracer) and new (one-sample, double-tracer infusion) methods were analysed in erythrocytes by Passing-Bablok and Altman-Bland tests. Muscle glutathione absolute synthesis rate increased following bed rest from 5.5 ± 1.1 to 11.0 ± 1.5 mmol (kg wet tissue)(-1) day(-1) (mean ± S.E.M.; n = 9; P = 0.02) while glutathione concentration failed to change significantly. Bed rest induced vastus lateralis muscle atrophy, as assessed by pennation angle changes measured by ultrasonography (from 18.6 ± 1.0 to 15.3 ± 0.9 deg; P = 0.01) and thickness changes (from 2.3 ± 0.2 to 1.9 ± 0.1 cm; P well as to compensatory activation of the glutathione system.

  15. Heart transplant

    Science.gov (United States)

    ... hospital for 7 to 21 days after a heart transplant. The first 24 to 48 hours will likely be in ... follow your self-care instructions. Biopsies of the heart muscle are ... after transplant, and then less often after that. This helps ...

  16. Resistance exercise training improves heart rate variability and muscle performance: a randomized controlled trial in coronary artery disease patients.

    Science.gov (United States)

    Caruso, F R; Arena, R; Phillips, S A; Bonjorno, J C; Mendes, R G; Arakelian, V M; Bassi, D; Nogi, C; Borghi-Silva, A

    2015-06-01

    Resistance exercise (RE) is an important part of cardiac rehabilitation. However, it is not known about the low intensity of RE training that could modify the heart rate variability (HRV), muscular strength and endurance in patients with coronary artery disease (CAD). To investigate the effects of high repetition/low load resistance training (HR/LL-RT) program on HRV and muscular strength and endurance in CAD patients. Randomized and controlled trial. Patients seen at the Cardiopulmonary Physical Therapy Laboratory between May 2011 and November 2013. Twenty male patients with CAD were randomized to a training group (61.3±5.2 years) or control group (61±4.4 years). 1 repetition maximum (1-RM) maneuver, discontinuous exercise test on the leg press (DET-L), and resting HRV were performed before and after 8 weeks of HR/LL-RT on a 45° leg press. RMSSD, SD1, mean HR and ApEn indices were calculated. The HR/LL-RT program consisted of a lower limb exercise using a 45° leg press; 3 sets of 20 repetitions, two times a week. The initial load was set at 30% of the 1-RM load and the duration of the HR/LL-RT program was performed for 8 weeks. After 8 weeks of HR/LL-RT there were significant increases of RMSSD and SD1 indices in the training group only (P<0.05). There was a significant decrease in mean HR after HR/LL-RT in the training group (P<0.05). There was a significantly higher ApEn after in the training group (P<0.05). There were significantly higher values in the training group in contrast to the control group (P<0.05). These results show positive improvements on HRV, as well as muscle strength and endurance in CAD patients. Eight weeks of HR/LL-RT is an effective sufficient to beneficially modify important outcomes as HRV, muscle strength and endurance in CAD patients.

  17. Nanonet force microscopy for measuring forces in single smooth muscle cells of the human aorta.

    Science.gov (United States)

    Hall, Alexander; Chan, Patrick; Sheets, Kevin; Apperson, Matthew; Delaughter, Christopher; Gleason, Thomas G; Phillippi, Julie A; Nain, Amrinder

    2017-07-07

    A number of innovative methods exist to measure cell-matrix adhesive forces, but they have yet to accurately describe and quantify the intricate interplay of a cell and its fibrous extracellular matrix (ECM). In cardiovascular pathologies, such as aortic aneurysm, new knowledge on the involvement of cell-matrix forces could lead to elucidation of disease mechanisms. To better understand this dynamics, we measured primary human aortic single smooth muscle cell (SMC) forces using nanonet force microscopy in both inside-out (I-O intrinsic contractility) and outside-in (O-I external perturbation) modes. For SMC populations, we measured the I-O and O-I forces to be 12.9 ± 1.0 and 57.9 ± 2.5 nN, respectively. Exposure of cells to oxidative stress conditions caused a force decrease of 57 and 48% in I-O and O-I modes, respectively, and an increase in migration rate by 2.5-fold. Finally, in O-I mode, we cyclically perturbed cells at constant strain of varying duration to simulate in vivo conditions of the cardiac cycle and found that I-O forces decrease with increasing duration and O-I forces decreased by half at shorter cycle times. Thus our findings highlight the need to study forces exerted and felt by cells simultaneously to comprehensively understand force modulation in cardiovascular disease. © 2017 Hall et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  18. Determining the impact of oxidation on the motility of single muscle-fibres expressing different myosin isoforms

    DEFF Research Database (Denmark)

    Spanos, Dimitrios; Li, M.; Baron, Caroline P.

    2013-01-01

    (motility speed) and force-generation capacity of specific MyHC isoforms. In the experimental procedure, single muscle fibres were split in different segments and each segment was exposed to a different concentration of hydrogen peroxide. Speed and force measurements were recorded and compared, to assess...... the effect of myosin oxidation on motility and force. The MyHC isoform expression in the single muscle fibre was subsequently determined on silver-stained gel SDS-PAGE. Preliminary results indicate a decrease of directionality and speed of the in-vitro motility as a result of an oxidative environment......, and the successful use of the assay in determining fibre-specific responses to oxidation. Subsequent analyses will focus on the location of protein modifications on the myosin molecule and on how these modifications induce changes in speed and force....

  19. Evaluation of regional pulmonary blood flow in mitral valvular heart disease using single-pass radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Chang-Soon Koh; Byung Tae Kim; Myung Chul Lee; Bo Yeon Cho

    1982-01-01

    Pulmonary hypertension in mitral valvular cardiac disease has been evaluated in 122 patients by a modified upper lung/lower count ratio using single-pass radionuclide angiocardiography. The mean upper lung/lower lung radio correlates well with pulmonary artery mean (r=0.483) and wedge pressure (r=0.804). After correction surgery of the cardiac valve, the ratio decreases and returns to normal range in patients judged clinically to have good surgical benifit. This modified method using single-pass technique provides additional simple, reproducible and nontraumatic results of regional pulmonary blood flow and appears to be correlated with the degree of pulmonary hypertension in mitral heart disease

  20. BUILDING A BETTER GLUTEAL BRIDGE: ELECTROMYOGRAPHIC ANALYSIS OF HIP MUSCLE ACTIVITY DURING MODIFIED SINGLE-LEG BRIDGES.

    Science.gov (United States)

    Lehecka, B J; Edwards, Michael; Haverkamp, Ryan; Martin, Lani; Porter, Kambry; Thach, Kailey; Sack, Richard J; Hakansson, Nils A

    2017-08-01

    Gluteal strength plays a role in injury prevention, normal gait patterns, eliminating pain, and enhancing athletic performance. Research shows high gluteal muscle activity during a single-leg bridge compared to other gluteal strengthening exercises; however, prior studies have primarily measured muscle activity with the active lower extremity starting in 90 ° of knee flexion with an extended contralateral knee. This standard position has caused reports of hamstring cramping, which may impede optimal gluteal strengthening. The purpose of this study was to determine which modified position for the single-leg bridge is best for preferentially activating the gluteus maximus and medius. Cross-Sectional. Twenty-eight healthy males and females aged 18-30 years were tested in five different, randomized single-leg bridge positions. Electromyography (EMG) electrodes were placed on subjects' gluteus maximus, gluteus medius, rectus femoris, and biceps femoris of their bridge leg (i.e., dominant or kicking leg), as well as the rectus femoris of their contralateral leg. Subjects performed a maximal voluntary isometric contraction (MVIC) for each tested muscle prior to performing five different bridge positions in randomized order. All bridge EMG data were normalized to the corresponding muscle MVIC data. A modified bridge position with the knee of the bridge leg flexed to 135 ° versus the traditional 90 ° of knee flexion demonstrated preferential activation of the gluteus maximus and gluteus medius compared to the traditional single-leg bridge. Hamstring activation significantly decreased (p bridge by flexing the active knee to 135 ° instead of 90 ° minimizes hamstring activity while maintaining high levels of gluteal activation, effectively building a bridge better suited for preferential gluteal activation. 3.

  1. Antioxidant defense system state in blood plasma and heart muscle of rats under the influence of histamine and sodium hypoclorite

    Directory of Open Access Journals (Sweden)

    O. I. Bishko

    2014-12-01

    Full Text Available There is a wide spectrum of antihistamine drugs in the pharmaceutical market, however all these chemical preparations cause side effects. Therefore, new alternative ways for histamine detoxication are to be found. For this aim in our experiment sodium hypochlorite was used because its solution possesses strong oxidizing properties. The influence of histamine and sodium hypochlorite on the antioxidant defence system state of blood plasma and cardiac muscle in rats has been researched. It was shown, that the investigated factors result in the disruption of the antioxidant system. It was found that histamine injection in concentration of 1 and 8 μg/kg in plasma leads to the increase of superoxi­de dismutase activity during all the experiment. When studying enzymes, that catalyze hydroperoxides and Н2О2 decomposition it was shown that under the influence of histamine in a dose 1 μg/kg, the glutathione peroxidase activity increased on the 1st day of the experiment. However, on the 7th day of the experiment the increase of both glutathione peroxidase and catalase activity was fixed. The deviation in superoxide dismutase function in rats plasma under the action of sodium hypochlorite has been established. The activity of enzymes that decompose Н2О2 and hydroperoxides were inhibi­ted. Under the influence of histamine in the heart tissues we have stated the disturbance of superoxide dismutase work and increase of catalase activity and decrease of glutathione peroxidase activity. The influence of sodium hypochlorite on the myocardium of intact animals as well as joint influence of sodium hypochlorite and histamine result in the increase of superoxide dismutase and catalase activity and lead to the conside­rable decline of activity of glutathione peroxidase.

  2. Single- and multiple-set resistance training improves skeletal and respiratory muscle strength in elderly women

    Directory of Open Access Journals (Sweden)

    Abrahin O

    2014-10-01

    Full Text Available Odilon Abrahin,1–3 Rejane P Rodrigues,1–3 Vanderson C Nascimento,3 Marzo E Da Silva-Grigoletto,1,4 Evitom C Sousa,3 Anderson C Marçal1,2 1Department of Physical Education, Federal University of Sergipe, Sergipe, Brazil; 2Center of Research in Intracellular Signaling, Department of Morphology, Federal University of Sergipe, Sergipe, Brazil; 3Laboratory of Resistance Exercise and Health, Sports Department, University of Pará State, Belem, Brazil; 4Scientific Sport, Sergipe, Brazil Introduction: Aging involves a progressive reduction of respiratory muscle strength as well as muscle strength. Purpose: Compare the effects of resistance training volume on the maximum inspiratory pressure (MIP, maximum expiratory pressure (MEP, functional performance, and muscle strength in elderly women. Methods: Thirty elderly women were randomly assigned to a group performing either single sets (1-SET or three sets (3-SET of exercises. The sit-to-stand test, MIP, MEP, and muscle strength were assessed before and after 24 training sessions. Progressive resistance training was performed two times per week for a total of 8–12 repetitions, using the main muscle groups of the upper and lower limbs. Results: The main results showed that the participants significantly increased their MEP (P<0.05; 1-SET: 34.6%; 3-SET: 35.8% and MIP (P<0.05; 1-SET: 13.7%; 3-SET: 11.2%. Both groups also improved in the sit-to-stand test (P<0.05; 1-SET: 10.6%; 3-SET: 17.1%. After 24 training sessions, muscle strength also significantly increased (P<0.0001; 40%–80% in both groups. An intergroup comparison did not show any statistically significant differences between the groups in any of the parameters analyzed. Conclusion: Single- and multiple-set resistance training programs increased MIP, MEP, muscle strength, and sit-to-stand test performance in elderly women after 24 sessions of training. In conclusion, our results suggested that elderly women who are not in the habit of

  3. Assessment of paraspinal muscle hardness in subjects with a mild single scoliosis curve: a preliminary myotonometer study.

    Science.gov (United States)

    Oliva-Pascual-Vaca, Ángel; Heredia-Rizo, Alberto Marcos; Barbosa-Romero, Alejandro; Oliva-Pascual-Vaca, Jesús; Rodríguez-Blanco, Cleofás; Tejero-García, Sergio

    2014-06-01

    The purpose of this study was to evaluate the hardness of the paraspinal muscles in the convexity and concavity of patients with scoliosis curvatures and in the upper trapezius (UT) muscle in subjects with mild idiopathic scoliosis (IS) and to observe the correlation between the myotonometer (MYO) measurements and the value of body mass index (BMI) and the Cobb angle. The sample included 13 patients with a single-curve mild IS (Risser sign ≤ 4) at thoracic, lumbar, or thoracolumbar level (mean Cobb angle of 11.53º). Seven females and 6 males were recruited, with a mean age of 12.84 ± 3.06 (9-18) years. A MYO was used to examine the differences in muscle hardness on both sides of the scoliosis curvature at several points: (a) apex of the curve, (b) upper and lower limits of the curve, and (c) the midpoint between the apex and the upper limit and between the apex and the lower limit. The UT was also explored. Although the MYO recorded lower values in all points on the concave side of the scoliosis, there were no significant differences in the comparison between sides (P > .05). No association was observed between BMI and MYO values, whereas the Cobb angle negatively correlated with muscle hardness only at 2 points on the convex side. The preliminary findings show that, in subjects with a single-curve mild IS, muscular hardness in the UT and paraspinal muscles, as assessed using a MYO, was not found to differ between the concave and the convex sides at different reference levels. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  4. Application of neuromuscular electrical stimulation of the lower limb skeletal muscles in the rehabilitation of patients with chronic heart failure and chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Ewa Barbara Kucio

    2017-03-01

    Full Text Available Increasing physical activity is a widely-known method of rehabilitation of patients with chronic heart failure (CHF and chronic obstructive pulmonary disease (COPD. However, what kind of procedure is to be applied if a patient suffers from advanced heart or respiratory failure, cannot undertake physical exercise due to locomotor system disorders or is currently undergoing respiratorotherapy? Recent research shows that neuromuscular electrical stimulation of the lower limb skeletal muscles (NMES may comprise an alternative to physical training in patients with CHF and COPD. The aim of this study is to summarize the current state of knowledge on the use of NMES in cardiac rehabilitation of patients with CHF and pulmonary rehabilitation of patients with COPD. As demonstrated in recent research on the topic, NMES – due to forcing the muscles to activate – increases exercise tolerance, muscle mass and endurance in patients with CHF and COPD. The beneficial effect of NMES on blood circulation in the muscles, aerobic enzymes activity, functioning of the vascular endothelium, reduction of pro-inflammatory cytokines concentration and increased quality of life has also been presented. It is to be accentuated that NMES treatment, due to lesser physical exertion and, in turn, a decreased feeling of dyspnea are more comfortable for the patient than traditional physical training. Moreover, NMES treatment, after foregoing training, can be applied at home. Potential side effects include transient muscle pain and minor skin damage due to improper positioning of the electrodes. To summarize, NMES treatment is well received by CHF and COPD patients and brings about increased exercise tolerance, as well as better quality of life. Devices used for NMES therapy, due to progressive miniaturization, are easily accessible and relatively inexpensive.

  5. Heart lesion after the first attack of the rheumatic Fever 22 years experience in single centre.

    Science.gov (United States)

    Bejiqi, Ramush A; Retkoceri, Ragip; Zeka, Naim; Bejiqi, Hana; Retkoceri, Arber

    2015-02-01

    Acute rheumatic fever and its sequels, rheumatic heart diseases, remain major unsolved preventable health problems in Kosovo population, particularly among the disadvantages indigenous Albanian and Egyptians people. In Kosovo, despite of performing secondary prophylaxis with benzathine penicillin, acute rheumatic fever hospitalization rates have remained essentially unchanged for the last 20 years. The role of echocardiography in the diagnosis of acute rheumatic carditis was established over the last 20 years. In this study we aimed to determine the prevalence of rheumatic heart disease in children from Kosovo population with first attack of acute rheumatic fever. Also, we presented that echocardiography examination detects a greater prevalence of rheumatic heart disease than other diagnostic procedures. We aimed to compare the sensitivity and specificity of cardiac auscultation, ECG record, lab analysis to echocardiography and to determine the feasibility of specific age in this setting. To optimize accurate diagnosis of rheumatic fever and rheumatic heart disease, we utilized two group models. In the first group of 388 children, hospitalized and treated before 1999, diagnosis of rheumatic fever was decided basing on the clinical and laboratory findings whereas in second group (221 children treated from1999 to 2010) clinical and lab diagnosis were amplified also on the detection by echocardiography. In second group, using echocardiography as a method of diagnosis and assessment children with rheumatic fever, we found high rates of undetected rheumatic heart disease in this high-risk group population. Echocardiographic examination of children with rheumatic fever for rheumatic heart disease may over diagnose rheumatic heart disease unless congenital mitral valve anomalies and physiological regurgitation are excluded.

  6. Heart Lesion After the First Attack of the Rheumatic Fever 22 Years Experience in Single Centre

    Science.gov (United States)

    Bejiqi, Ramush A.; Retkoceri, Ragip; Zeka, Naim; Bejiqi, Hana; Retkoceri, Arber

    2015-01-01

    Background: Acute rheumatic fever and its sequels, rheumatic heart diseases, remain major unsolved preventable health problems in Kosovo population, particularly among the disadvantages indigenous Albanian and Egyptians people. In Kosovo, despite of performing secondary prophylaxis with benzathine penicillin, acute rheumatic fever hospitalization rates have remained essentially unchanged for the last 20 years. The role of echocardiography in the diagnosis of acute rheumatic carditis was established over the last 20 years. Aims: In this study we aimed to determine the prevalence of rheumatic heart disease in children from Kosovo population with first attack of acute rheumatic fever. Also, we presented that echocardiography examination detects a greater prevalence of rheumatic heart disease than other diagnostic procedures. We aimed to compare the sensitivity and specificity of cardiac auscultation, ECG record, lab analysis to echocardiography and to determine the feasibility of specific age in this setting. Methods: To optimize accurate diagnosis of rheumatic fever and rheumatic heart disease, we utilized two group models. In the first group of 388 children, hospitalized and treated before 1999, diagnosis of rheumatic fever was decided basing on the clinical and laboratory findings whereas in second group (221 children treated from1999 to 2010) clinical and lab diagnosis were amplified also on the detection by echocardiography. Conclusion: In second group, using echocardiography as a method of diagnosis and assessment children with rheumatic fever, we found high rates of undetected rheumatic heart disease in this high-risk group population. Echocardiographic examination of children with rheumatic fever for rheumatic heart disease may over diagnose rheumatic heart disease unless congenital mitral valve anomalies and physiological regurgitation are excluded. PMID:25870479

  7. Twelve actin-encoding cDNAs from the American lobster, Homarus americanus: cloning and tissue expression of eight skeletal muscle, one heart, and three cytoplasmic isoforms.

    Science.gov (United States)

    Kim, Bo Kwang; Kim, Kyoung Sun; Oh, Chul-Woong; Mykles, Donald L; Lee, Sung Gu; Kim, Hak Jun; Kim, Hyun-Woo

    2009-06-01

    Lobster muscles express a diverse array of myofibrillar protein isoforms. Three fiber types (fast, slow-twitch or S1, and slow-tonic or S2) differ qualitatively and quantitatively in myosin heavy and light chains, troponin-T, -I, and -C, paramyosin, and tropomyosin variants. However, little is known about the diversity of actin isoforms present in crustacean tissues. In this report we characterized cDNAs that encode twelve actin isoforms in the American lobster, Homarus americanus: eight from skeletal muscle (Ha-ActinSK1-8), one from heart (Ha-ActinHT1), and three cytoplasmic type actins from hepatopancreas (Ha-ActinCT1-3). All twelve cDNAs were products of distinct genes, as indicated by differences in the 3'-untranslated regions (UTRs). The open reading frames specified polypeptides 376 or 377 amino acids in length. Although key amino residues are conserved in the lobster actins, variations in nearby sequences may affect actin polymerization and/or interactions with other myofibrillar proteins. Quantitative reverse transcription-polymerase chain reaction showed muscle fiber type- and tissue-specific expression patterns. Ha-Actin-HT1 was expressed exclusively in heart (87% of the total; 12% of the total was Ha-ActinCT1). Ha-ActinCT1 was expressed in all tissues, while CT2 and CT3 were expressed only in hepatopancreas, with Ha-ActinCT2 as the major isoform (93% of the total). Ha-ActinSK1 and SK2 were the major isoforms (88% and 12% of the total, respectively) in the S1 fibers of crusher claw closer muscle. Fast fibers in the cutter claw closer and deep abdominal muscles differed in SK isoforms. Ha-ActinSK3, SK4, and SK5 were the major isoforms in cutter claw closer muscle (12%, 48%, and 37% of the total, respectively). Ha-ActinSK5 and SK8 were the major isoforms in deep abdominal flexor (31% and 65% of the total, respectively) and extensor (46% and 53% of the total, respectively) muscles, with SK6 and SK7 expressed at low levels. These data indicate that fast

  8. Inspiratory Muscle Training and Functional Electrical Stimulation for Treatment of Heart Failure With Preserved Ejection Fraction: Rationale and Study Design of a Prospective Randomized Controlled Trial.

    Science.gov (United States)

    Palau, Patricia; Domínguez, Eloy; López, Laura; Heredia, Raquel; González, Jessika; Ramón, Jose María; Serra, Pilar; Santas, Enrique; Bodi, Vicente; Sanchis, Juan; Chorro, Francisco J; Núñez, Julio

    2016-08-01

    Heart failure with preserved ejection fraction (HFpEF) has become the most prevalent form of heart failure in developed countries. Regrettably, there is no evidence-based effective therapy for HFpEF. We seek to evaluate whether inspiratory muscle training, functional electrical stimulation, or a combination of both can improve exercise capacity as well as left ventricular diastolic function, biomarker profile, quality of life (QoL), and prognosis in patients with HFpEF. A total of 60 stable symptomatic patients with HFpEF (New York Heart Association class II-III/IV) will be randomized (1:1:1:1) to receive a 12-week program of inspiratory muscle training, functional electrical stimulation, a combination of both, or standard care alone. The primary endpoint of the study is change in peak exercise oxygen uptake; secondary endpoints are changes in QoL, echocardiogram parameters, and prognostic biomarkers. As of March 21, 2016, thirty patients have been enrolled. Searching for novel therapies that improve QoL and autonomy in the elderly with HFpEF has become a health care priority. We believe that this study will add important knowledge about the potential utility of 2 simple and feasible physical interventions for the treatment of advanced HFpEF. © 2016 Wiley Periodicals, Inc.

  9. Assessment of image quality of 64-row Dual Source versus Single Source CT coronary angiography on heart rate : A phantom study

    NARCIS (Netherlands)

    Dikkers, R.; Greuter, M. J. W.; Kristanto, W.; van Ooijen, P. M. A.; Sijens, P. E.; Willems, T. P.; Oudkerk, M.

    Purpose: To assess the influence of temporal resolution on image quality of computed tomographic (CT) coronary angiography by comparing 64-row Dual Source CT (DSCT) and Single Source CT (SSCT) at different heart rates. Methods: An anthropomorphic moving heart phantom was scanned at rest, and at 50

  10. Non-Targeted Metabolomics Analysis of the Effects of Tyrosine Kinase Inhibitors Sunitinib and Erlotinib on Heart, Muscle, Liver and Serum Metabolism In Vivo

    Directory of Open Access Journals (Sweden)

    Brian C. Jensen

    2017-06-01

    Full Text Available Background: More than 90 tyrosine kinases have been implicated in the pathogenesis of malignant transformation and tumor angiogenesis. Tyrosine kinase inhibitors (TKIs have emerged as effective therapies in treating cancer by exploiting this kinase dependency. The TKI erlotinib targets the epidermal growth factor receptor (EGFR, whereas sunitinib targets primarily vascular endothelial growth factor receptor (VEGFR and platelet-derived growth factor receptor (PDGFR.TKIs that impact the function of non-malignant cells and have on- and off-target toxicities, including cardiotoxicities. Cardiotoxicity is very rare in patients treated with erlotinib, but considerably more common after sunitinib treatment. We hypothesized that the deleterious effects of TKIs on the heart were related to their impact on cardiac metabolism. Methods: Female FVB/N mice (10/group were treated with therapeutic doses of sunitinib (40 mg/kg, erlotinib (50 mg/kg, or vehicle daily for two weeks. Echocardiographic assessment of the heart in vivo was performed at baseline and on Day 14. Heart, skeletal muscle, liver and serum were flash frozen and prepped for non-targeted GC-MS metabolomics analysis. Results: Compared to vehicle-treated controls, sunitinib-treated mice had significant decreases in systolic function, whereas erlotinib-treated mice did not. Non-targeted metabolomics analysis of heart identified significant decreases in docosahexaenoic acid (DHA, arachidonic acid (AA/ eicosapentaenoic acid (EPA, O-phosphocolamine, and 6-hydroxynicotinic acid after sunitinib treatment. DHA was significantly decreased in skeletal muscle (quadriceps femoris, while elevated cholesterol was identified in liver and elevated ethanolamine identified in serum. In contrast, erlotinib affected only one metabolite (spermidine significantly increased. Conclusions: Mice treated with sunitinib exhibited systolic dysfunction within two weeks, with significantly lower heart and skeletal muscle

  11. Ca2+-activated force-generating properties of mammalian skeletal muscle fibres: histochemically identified single peeled rabbit fibres.

    Science.gov (United States)

    Donaldson, S K

    1984-12-01

    Single peeled (sarcolemma removed) rabbit skeletal muscle fibres, identified histochemically from their myofibrillar ATPase and oxidative staining patterns, were characterized according to their Ca2+-activated steady-state force-generating properties at normal intracellular pH (7.0) and under acidotic (pH 6.5) conditions. Maximum force-generating capacity of each fibre was assessed by measuring steady-state isometric force generation at saturating Ca2+ concentration at both pH values. The Ca2+ sensitivity of each fibre was ascertained by determining the percentage of maximum force generated at each of several subsaturating Ca2+ concentrations at both pH values. Fibres were selected from soleus, tibialis anterior and adductor magnus muscles. At subsaturating Ca2+ concentrations only two functional groups of fibres were distinguishable, corresponding to the histochemical classifications type I and type II. Type I fibres were more sensitive to Ca2+ and less depressed by acidosis than type II fibres in the subsaturating range of Ca2+ concentrations. At saturating Ca2+ concentrations, the acidotic depression of maximum force was significantly less for type I fibres than type II nonoxidative fibres regardless of their muscle of origin. Type II oxidative fibre maximum force properties depended upon the muscle of origin and demonstrated subgroups of these fibres that were different from type II nonoxidative fibres and similar to type I fibres.

  12. Deletion of a single-copy DAAM1 gene in congenital heart defect: a case report

    Directory of Open Access Journals (Sweden)

    Bao Bihui

    2012-08-01

    Full Text Available Abstract Background With an increasing incidence of congenital heart defects (CHDs in recent years, genotype-phenotype correlation and array-based methods have contributed to the genome-wide analysis and understanding of genetic variations in the CHD population. Here, we report a copy number deletion of chromosomal 14q23.1 in a female fetus with complex congenital heart defects. This is the first description of DAAM1 gene deletion associated with congenital heart anomalies. Case Presentation Compared with the control population, one CHD fetus showed a unique copy number deletion of 14q23.1, a region that harbored DAAM1 and KIAA0666 genes. Conclusions Results suggest that the copy number deletion on chromosome 14q23.1 may be critical for cardiogenesis. However, the exact relationship and mechanism of how DAAM1 and KIAA0666 deletion contributes to the onset of CHD is yet to be determined.

  13. Intracellular β2-adrenergic receptor signaling specificity in mouse skeletal muscle in response to single-dose β2-agonist clenbuterol treatment and acute exercise.

    Science.gov (United States)

    Sato, Shogo; Shirato, Ken; Mitsuhashi, Ryosuke; Inoue, Daisuke; Kizaki, Takako; Ohno, Hideki; Tachiyashiki, Kaoru; Imaizumi, Kazuhiko

    2013-05-01

    The aim of this study was to clarify the intracellular β2-adrenergic receptor signaling specificity in mouse slow-twitch soleus and fast-twitch tibialis anterior (TA) muscles, resulting from single-dose β2-agonist clenbuterol treatment and acute exercise. At 1, 4, and 24 h after single-dose treatment with clenbuterol or after acute running exercise, the soleus and TA muscles were isolated and subjected to analysis. The phosphorylation of p38 mitogen-activated protein kinase (MAPK) increased after single-dose clenbuterol treatment and acute exercise in the soleus muscle but not in the TA muscle. Although there was no change in the phosphorylation of Akt after acute exercise in either muscle, phosphorylation of Akt in the soleus muscle increased after single-dose clenbuterol treatment, whereas that in the TA muscle remained unchanged. These results suggest that p38 MAPK and Akt pathways play a functional role in the adaptation to clenbuterol treatment and exercise, particularly in slow-twitch muscles.

  14. Investigating reduction of dimensionality during single-joint elbow movements: a case study on muscle synergies

    Directory of Open Access Journals (Sweden)

    Enrico eChiovetto

    2013-02-01

    Full Text Available A long standing hypothesis in the neuroscience community is that the CNS generates the muscle activities to accomplish movements by combining a relatively small number of stereotyped patterns of muscle activations, often referred to as muscle synergies. Different definitions of synergies have been given in the literature. The most well-known are those of synchronous, time-varying and temporal muscle synergies. Each one of them is based on a different mathematical model used to factor some EMG array recordings collected during the execution of variety of motor tasks into a well-determined spatial, temporal or spatio-temporal organization. This plurality of definitions and their separate application to complex tasks have so far complicated the comparison and interpretation of the results obtained across studies, and it has always remained unclear why and when one synergistic decomposition should be preferred to another one. By using well-understood motor tasks such as elbow flexions and extensions, we aimed in this study to clarify better what are the motor features characterized by each kind of decomposition and to assess whether, when and why one of them should be preferred to the others. We found that three temporal synergies, each one of them accounting for specific temporal phases of the movements could account for the majority of the data variation. Similar performances could be achieved by two synchronous synergies, encoding the agonist-antagonist nature of the two muscles considered, and by two time-varying muscle synergies, encoding each one a task-related feature of the elbow movements, specifically their direction. Our findings support the notion that each EMG decomposition provides a set of well-interpretable muscle synergies, identifying reduction of dimensionality in different aspects of the movements. Taken together, our findings suggest that all decompositions are not equivalent and may imply different neurophysiological substrates

  15. Investigating reduction of dimensionality during single-joint elbow movements: a case study on muscle synergies.

    Science.gov (United States)

    Chiovetto, Enrico; Berret, Bastien; Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry

    2013-01-01

    A long standing hypothesis in the neuroscience community is that the central nervous system (CNS) generates the muscle activities to accomplish movements by combining a relatively small number of stereotyped patterns of muscle activations, often referred to as "muscle synergies." Different definitions of synergies have been given in the literature. The most well-known are those of synchronous, time-varying and temporal muscle synergies. Each one of them is based on a different mathematical model used to factor some EMG array recordings collected during the execution of variety of motor tasks into a well-determined spatial, temporal or spatio-temporal organization. This plurality of definitions and their separate application to complex tasks have so far complicated the comparison and interpretation of the results obtained across studies, and it has always remained unclear why and when one synergistic decomposition should be preferred to another one. By using well-understood motor tasks such as elbow flexions and extensions, we aimed in this study to clarify better what are the motor features characterized by each kind of decomposition and to assess whether, when and why one of them should be preferred to the others. We found that three temporal synergies, each one of them accounting for specific temporal phases of the movements could account for the majority of the data variation. Similar performances could be achieved by two synchronous synergies, encoding the agonist-antagonist nature of the two muscles considered, and by two time-varying muscle synergies, encoding each one a task-related feature of the elbow movements, specifically their direction. Our findings support the notion that each EMG decomposition provides a set of well-interpretable muscle synergies, identifying reduction of dimensionality in different aspects of the movements. Taken together, our findings suggest that all decompositions are not equivalent and may imply different neurophysiological

  16. Single rat muscle Na+channel mutation confers batrachotoxin autoresistance found in poison-dart frogPhyllobates terribilis.

    Science.gov (United States)

    Wang, Sho-Ya; Wang, Ging Kuo

    2017-09-26

    Poison-dart Phyllobates terribilis frogs sequester lethal amounts of steroidal alkaloid batrachotoxin (BTX) in their skin as a defense mechanism against predators. BTX targets voltage-gated Na + channels and enables them to open persistently. How BTX autoresistance arises in such frogs remains a mystery. The BTX receptor has been delineated along the Na + channel inner cavity, which is formed jointly by four S6 transmembrane segments from domains D1 to D4. Within the P. terribilis muscle Na + channel, five amino acid (AA) substitutions have been identified at D1/S6 and D4/S6. We therefore investigated the role of these naturally occurring substitutions in BTX autoresistance by introducing them into rat Nav1.4 muscle Na + channel, both individually and in combination. Our results showed that combination mutants containing an N1584T substitution all conferred a complete BTX-resistant phenotype when expressed in mammalian HEK293t cells. The single N1584T mutant also retained its functional integrity and became exceptionally resistant to 5 µM BTX, aside from a small residual BTX effect. Single and combination mutants with the other four S6 residues (S429A, I433V, A445D, and V1583I) all remained highly BTX sensitive. These findings, along with diverse BTX phenotypes of N1584K/A/D/T mutant channels, led us to conclude that the conserved N1584 residue is indispensable for BTX actions, probably functioning as an integral part of the BTX receptor. Thus, complete BTX autoresistance found in P. terribilis muscle Na + channels could emerge primarily from a single AA substitution (asparagine→threonine) via a single nucleotide mutation (AAC→ACC).

  17. Electrophysiologic evaluation of lumbosacral single nerve roots using compound muscle action potentials.

    Science.gov (United States)

    Ogura, Taku; Shikata, Hideto; Hase, Hitoshi; Mori, Masaki; Hayashida, Taturo; Osawa, Toru; Mikami, Yasuo; Kubo, Toshikazu

    2003-10-01

    Transcutaneous electrical stimulation applied to the vertebral column produces compound muscle action potentials (CMAPs) from the leg muscles. Using this method, we evaluated the efferent pathways of the lumbosacral nerve roots. The subjects were 26 healthy volunteers and 31 patients with lumbar disc herniation (LDH). CMAP recordings were obtained from the bilateral vastus medialis, tibialis anterior, extensor digitorum brevis, and abductor hallucis muscles using low-output-impedance stimulation. In normal subjects, the CMAP latency increased linearly with the distance between the stimulating electrode and the recording electrode, with little difference in latency between the left and the right sides in each subject. The CMAP amplitude was significantly lower in the patients with LDH, and the latency was also prolonged when the stimulating electrode was placed above the lesion. This technique may thus be a useful noninvasive method for assessing lumbosacral nerve root function in patients with LDH.

  18. Heart Rate Variability Biofeedback Stress Relief Program for Depression A Replicated Single-Subject Design

    NARCIS (Netherlands)

    Hartogs, Bregje M. A.; Bartels-Velthuis, Agna A.; Van der Ploeg, Karen; Bos, Elske H.

    2017-01-01

    Background: Depressive disorders often have a chronic course and the efficacy of evidence-based treatments may be overestimated. Objective: To examine the effectiveness of the Heart Rate Variability Stress Reduction Program (SRP) as a supplement to standard treatment in patients with depressive

  19. The effects of aging, physical training, and a single bout of exercise on mitochondrial protein expression in human skeletal muscle.

    Science.gov (United States)

    Bori, Zoltan; Zhao, Zhongfu; Koltai, Erika; Fatouros, Ioannis G; Jamurtas, Athanasios Z; Douroudos, Ioannis I; Terzis, Gerasimos; Chatzinikolaou, Athanasios; Sovatzidis, Apostolos; Draganidis, Dimitrios; Boldogh, Istvan; Radak, Zsolt

    2012-06-01

    Aging results in a significant decline in aerobic capacity and impaired mitochondrial function. We have tested the effects of moderate physical activity on aerobic capacity and a single bout of exercise on the expression profile of mitochondrial biogenesis, and fusion and fission related genes in skeletal muscle of human subjects. Physical activity attenuated the aging-associated decline in VO2 max (pAging increased and a single exercise bout decreased the expression of nuclear respiratory factor-1 (NRF1), while the transcription factor A (TFAM) expression showed a strong relationship with VO(2max) and increased significantly in the young physically active group. Mitochondrial fission representing FIS1 was induced by regular physical activity, while a bout of exercise decreased fusion-associated gene expression. The expression of polynucleotide phosphorylase (PNPase) changed inversely in young and old groups and decreased with aging. The A2 subunit of cyclic AMP-activated protein kinase (AMPK) was induced by a single bout of exercise in skeletal muscle samples of both young and old subjects (pphysical activity increases a larger number of mitochondrial biogenesis-related gene expressions in young individuals than in aged subjects. Mitochondrial fission is impaired by aging and could be one of the most sensitive markers of the age-associated decline in the adaptive response to physical activity. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Heart Lesion After the First Attack of the Rheumatic Fever 22 Years Experience in Single Centre

    OpenAIRE

    Bejiqi, Ramush A.; Retkoceri, Ragip; Zeka, Naim; Bejiqi, Hana; Retkoceri, Arber

    2015-01-01

    Background: Acute rheumatic fever and its sequels, rheumatic heart diseases, remain major unsolved preventable health problems in Kosovo population, particularly among the disadvantages indigenous Albanian and Egyptians people. In Kosovo, despite of performing secondary prophylaxis with benzathine penicillin, acute rheumatic fever hospitalization rates have remained essentially unchanged for the last 20 years. The role of echocardiography in the diagnosis of acute rheumatic carditis was estab...

  1. A single German center experience with intermittent inotropes for patients on the high-urgent heart transplant waiting list.

    Science.gov (United States)

    Hübner, T; Nickel, T; Steinbeck, G; Massberg, S; Schramm, R; Reichart, B; Hagl, C; Kiwi, A; Weis, Michael

    2015-11-01

    Currently, more than 900 patients with end-stage heart failure are listed for heart transplantation in Germany. All patients on the Eurotransplant high-urgent status (HU) have to be treated in intensive care units and have to be relisted every 8 weeks. Long-term continuous inotropes are associated with tachyphylaxia, arrhythmias and even increased mortality. In this retrospective analysis, we report our single center experience with HU patients treated with intermittent inotropes as a bridging therapy. 117 consecutive adult HU candidates were treated at our intensive care heart failure unit between 2008 and 2013, of whom 14 patients (12 %) were stabilized and delisted during follow-up. In the remaining 103 patients (age 42 ± 15 years), different inotropes (dobutamine, milrinone, adrenaline, noradrenaline, levosimendan) were administered based on the patient's specific characteristics. After initial recompensation, patients were weaned from inotropes as soon as possible. Thereafter, intermittent inotropes (over 3-4 days) were given as a predefined weekly (until 2011) or 8 weekly regimen (from 2011 to 2013). In 57 % of these patients, additional regimen-independent inotropic support was necessary due to hemodynamic instabilities. Fourteen patients (14 %) needed a left- or biventricular assist device; 14 patients (14 %) died while waiting and 87 (84 %) received heart transplants after 87 ± 91 days. Cumulative 3 and 12 months survival of all 103 patients was 75 and 67 %, respectively. Intermittent inotropes in HU patients are an adequate strategy as a bridge to transplant; the necessity for assist devices was low. These data provide the basis for a prospective multicenter trial of intermittent inotropes in patients on the HU waiting list.

  2. Evaluation of single right atrial volume and function with magnetic resonance imaging in children with hypoplastic left heart

    International Nuclear Information System (INIS)

    Vijarnsorn, Chodchanok; Myers, Kimberley; Patton, David J.; Noga, Michelle; Crawley, Cinzia; Tham, Edythe

    2016-01-01

    Standardized methods to evaluate atrial properties in single ventricles are lacking. To determine the feasibility of quantifying right atrial volumes and function in hypoplastic left heart using MRI. We studied 15 infants with hypoplastic left heart prior to Glenn surgery (mean age 4.2 months [standard deviation 0.3]) who underwent cardiac MRI with evaluation of atrial volumes and emptying fraction using monoplane two-chamber, monoplane four-chamber, and biplane methods, all of which were compared to the atrial short-axial oblique stack method. We compared atrial end-diastolic volume, end-systolic volume and emptying fraction among these methods. We analyzed reproducibility of the methods using Bland-Altman plots. Both four-chamber and biplane methods showed high correlations for atrial end-diastolic volume (r = 0.7 and r = 0.8, respectively; P < 0.01) and end-systolic volume (r = 0.8 and r = 0.9, respectively; P < 0.01) with small mean differences (-0.2 ± 2.9 standard deviation [SD] ml and -0.8 ± 1.6 ml, respectively, for atrial end-diastolic volume and -0.8 ± 1.5 ml and -0.9 ± 0.9 ml, respectively, for atrial end-systolic volume). The short-axial oblique method was the most reproducible, followed by the four-chamber method. MRI assessment of atrial volume and function is feasible in hypoplastic left heart and might provide further insight into single-ventricle mechanics. (orig.)

  3. Evaluation of single right atrial volume and function with magnetic resonance imaging in children with hypoplastic left heart

    Energy Technology Data Exchange (ETDEWEB)

    Vijarnsorn, Chodchanok [University of Alberta, Faculty of Medicine and Dentistry, Stollery Children' s Hospital, Edmonton, AB (Canada); Mahidol University, Siriraj Hospital, Bangkok (Thailand); Myers, Kimberley; Patton, David J. [Alberta Children' s Hospital, Section of Pediatric Cardiology, Department of Pediatrics, Department of Pediatrics, Calgary, AB (Canada); Noga, Michelle; Crawley, Cinzia; Tham, Edythe [University of Alberta, Faculty of Medicine and Dentistry, Stollery Children' s Hospital, Edmonton, AB (Canada)

    2016-06-15

    Standardized methods to evaluate atrial properties in single ventricles are lacking. To determine the feasibility of quantifying right atrial volumes and function in hypoplastic left heart using MRI. We studied 15 infants with hypoplastic left heart prior to Glenn surgery (mean age 4.2 months [standard deviation 0.3]) who underwent cardiac MRI with evaluation of atrial volumes and emptying fraction using monoplane two-chamber, monoplane four-chamber, and biplane methods, all of which were compared to the atrial short-axial oblique stack method. We compared atrial end-diastolic volume, end-systolic volume and emptying fraction among these methods. We analyzed reproducibility of the methods using Bland-Altman plots. Both four-chamber and biplane methods showed high correlations for atrial end-diastolic volume (r = 0.7 and r = 0.8, respectively; P < 0.01) and end-systolic volume (r = 0.8 and r = 0.9, respectively; P < 0.01) with small mean differences (-0.2 ± 2.9 standard deviation [SD] ml and -0.8 ± 1.6 ml, respectively, for atrial end-diastolic volume and -0.8 ± 1.5 ml and -0.9 ± 0.9 ml, respectively, for atrial end-systolic volume). The short-axial oblique method was the most reproducible, followed by the four-chamber method. MRI assessment of atrial volume and function is feasible in hypoplastic left heart and might provide further insight into single-ventricle mechanics. (orig.)

  4. Comparison of single- or multifrequency bioelectrical impedance analysis and spectroscopy for assessment of appendicular skeletal muscle in the elderly.

    Science.gov (United States)

    Yamada, Yosuke; Watanabe, Yuya; Ikenaga, Masahiro; Yokoyama, Keiichi; Yoshida, Tsukasa; Morimoto, Taketoshi; Kimura, Misaka

    2013-09-01

    Bioelectrical impedance analysis (BIA) is used to assess skeletal muscle mass, although its application in the elderly has not been fully established. Several BIA modalities are available: single-frequency BIA (SFBIA), multifrequency BIA (MFBIA), and bioelectrical impedance spectroscopy (BIS). The aim of this study was to examine the difference between SFBIA, MFBIA, and BIS for assessment of appendicular skeletal muscle strength in the elderly. A total of 405 elderly (74.2 ± 5.0 yr) individuals were recruited. Grip strength and isometric knee extension strength were measured. Segmental SFBIA, MFBIA, and BIS were measured for the arms and upper legs. Bioelectrical impedance indexes were calculated by squared segment length divided by impedance (L2/Z). Impedance at 5 and 50 kHz (Z5 and Z50) was used for SFBIA. Impedance of the intracellular component was calculated from MFBIA (Z250-5) and BIS (RICW). Correlation coefficients between knee extension strength and L2/Z5, L2/Z50, L2/RICW, and L2/Z250-5 of the upper legs were 0.661, 0.705, 0.790, and 0.808, respectively (P < 0.001). Correlation coefficients were significantly greater for MFBIA and BIS than SFBIA. Receiver operating characteristic curves showed that L2/Z250-5 and L2/RICW had significantly larger areas under the curve for the diagnosis of muscle weakness compared with L2/Z5 and L2/Z50. Very similar results were observed for grip strength. Our findings suggest that MFBIA and BIS are better methods than SFBIA for assessing skeletal muscle strength in the elderly.

  5. Impact of a single session of intermittent pneumatic leg compressions on skeletal muscle and isolated artery gene expression in rats.

    Science.gov (United States)

    Roseguini, Bruno T; Arce-Esquivel, Arturo A; Newcomer, Sean C; Laughlin, M H

    2011-12-01

    Intermittent pneumatic leg compressions (IPC) have proven to be an effective noninvasive approach for treatment of patients with claudication, but the mechanisms underlying the clinical benefits remain elusive. In the present study, a rodent model of claudication produced by bilateral ligation of the femoral artery was used to investigate the acute impact of a single session of IPC (150 min) on hemodynamics, skeletal muscle (tibialis anterior), and isolated collateral artery (perforating artery) expression of a subset of genes associated with inflammation and vascular remodeling. In addition, the effect of compression frequency (15 vs. 3 compressions/min) on the expression of these factors was studied. In ligated animals, IPC evoked an increase of monocyte chemoattractant protein-1 (MCP-1) and cytokine-induced neutrophil chemoattractant 1 (CXCL1) mRNA (P < 0.01) and immunostaining (P < 0.05), as well as a minor increase in VEGF immunostaining in the muscle endomysium 150 min postintervention. Further, collateral arteries from these animals showed an increased expression of MCP-1 (approximately twofold, P = 0.02). These effects were most evident in the group exposed to the high-frequency protocol (15 compressions/min). In contrast, IPC in sham-operated control animals evoked a modest initial upregulation of VEGF (P = 0.01), MCP-1 (P = 0.02), and CXCL1 (P = 0.03) mRNA in the muscle without concomitant changes in protein levels. No changes in gene expression were observed in arteries isolated from sham animals. In conclusion, IPC acutely up-regulates the expression of important factors involved in vascular remodeling in the compressed muscle and collateral arteries in a model of hindlimb ischemia. These effects appear to be dependent on the compression frequency, such that a high compression frequency (15 compressions/min) evokes more consistent and robust effects compared with the frequency commonly employed clinically to treat patients with claudication (3

  6. Single motor unit firing behaviour in the right trapezius muscle during rapid movement of right or left index finger.

    Directory of Open Access Journals (Sweden)

    Karen eSøgaard

    2014-11-01

    Full Text Available Computer work is associated with low level sustained activity in the trapezius muscle that may cause myalgia. The activity may be attention related or part of a general multijoint motor program providing stabilization of the shoulder girdle for precise finger manipulation. This study examines single motor unit (MU firing pattern in the right trapezius muscle during fast movements of ipsi or contralateral index finger. Modulated firing rate would support a general multi joint motor program, while a generally increased and continuous firing rate would support attention related activation. 12 healthy female subjects were seated at a computer work place with elbows and forearms supported. Ten double clicks (DC were performed with right and left index finger on a computer mouse instrumented with a trigger.Surface EMG was recorded from right and left trapezius muscle. Intramuscular EMG was recorded with a quadripolar wire electrode in the right trapezius.Surface EMG was analysed as %MVE. The intramuscular EMG was decomposed into individual MU action potential trains. Instantaneous firing rate (IFR was calculated from inter-spike interval with ISI shorter than 20 ms defined as doublets. IFR was averaged across 10 DC to show IFR modulation.Surface EMG in both right and left trapezius was 1.8-2.5%MVE. During right hand DC a total of 32 MUs were identified. Four subjects showed no activity. Four showed MU activity with weak or no variations related to the timing of DC. Four subjects showed large modulation in IFR with temporal relation to DC. During left hand DC 15 MUs were identified in 4 subjects, for two of the subjects with IFR modulations related to DC. Doublets was found as an integrated part of MU activation in the trapezius muscle and for one subject temporarily related to DC. In conclusion, DC with ipsi- and contralateral fast movements of the index finger was found to evoke biomechanically as well as attention related activity pattern in the

  7. Controlled intermittent shortening contractions of a muscle-tendon complex: muscle fibre damage and effects on force transmission from a single head of rat EDL

    NARCIS (Netherlands)

    Maas, H.; Lehti, T.M.; Tiihonen, V.; Komulainen, J.; Huijing, P.A.J.B.M.

    2005-01-01

    This study was performed to examine effects of prolonged (3 h) intermittent shortening (amplitude 2 mm) contractions (muscles were excited maximally) of head III of rat extensor digitorum longus muscle (EDL III) on indices of muscle damage and on force transmission within the intact anterior crural

  8. Development of heart muscle-cell diversity: a help or a hindrance for phenotyping embryonic stem cell-derived cardiomyocytes

    NARCIS (Netherlands)

    Fijnvandraat, Arnoud C.; Lekanne Deprez, Ronald H.; Moorman, Antoon F. M.

    2003-01-01

    Despite the advances in cardiovascular treatment, cardiac disease remains a major cause of morbidity in all industrialized countries. The extraordinary potential of (embryonic) stem cells for therapeutic purposes has revolutionized ideas about cardiac repair of diseased cardiac muscle to exciting

  9. Correlation of single-breath count test and neck flexor muscle strength with spirometry in myasthenia gravis.

    Science.gov (United States)

    Elsheikh, Bakri; Arnold, W David; Gharibshahi, Shahram; Reynolds, Jerold; Freimer, Miriam; Kissel, John T

    2016-01-01

    Although formal spirometry is the gold standard for monitoring respiratory function in patients with myasthenia gravis (MG), such testing is often delayed or unavailable. There is a need for a simple bedside test that can accurately measure respiratory function. We conducted a prospective, cross-sectional, single-blind study in adults with acetylcholine receptor antibody positive MG. Participants performed the single breath count test (SBCT) and underwent manual muscle strength testing, and a respiratory therapist performed spirometry blinded to SBCT and strength results. Thirty-one patients, aged 57 ± 19 years participated. SBCT showed significant correlations with forced vital capacity (FVC), negative inspiratory force, and neck flexor strength (P strength (P = 0.02) but no correlation with shoulder abductor strength. These data suggest that the SBCT and neck flexor strength testing are valuable tools for bedside assessment of respiratory function in MG patients. © 2015 Wiley Periodicals, Inc.

  10. Challenges in the management of congenital heart disease in Vietnam: A single center experience

    International Nuclear Information System (INIS)

    Phuc, Vu Minh; Tin, Do Nguyen; Giang, Do Thi Cam

    2015-01-01

    Vietnam, in Asia, is a low middle-income country with a relatively large population to cater to. Not many know about Vietnam, or its healthcare sector especially the field of pediatric cardiology and congenital heart disease. In contrast to the developed world, congenital heart disease (CHD) is not diagnosed early. Since most of the patients visit the hospital only in later stages of the disease there are many complications during the operation and post-operatively. But during the past 5 years (from 2009), there has been major improvement in the treatment of CHD, both by intervention and surgery. At present, all kinds of CHD, both simple and complex are being successfully treated in our country. Today in Vietnam, all children under 6 years of age have health insurance coverage, under which almost all operations and catheter interventions are done free in government hospitals. It is helping many patients, especially those from the poor socioeconomic background. However, the present infrastructure is inadequate and a long waiting list has accumulated for treatment of CHD

  11. Sleep Apnoea Detection in Single Channel ECGs by Analyzing Heart Rate Dynamics

    National Research Council Canada - National Science Library

    Zywietz, C

    2001-01-01

    .... Sleep disorders are typically investigated by means of polysomnographic recordings. We have analyzed 70 eight-hour single-channel ECG recordings to find out to which extent sleep apneas may be detected from the ECG alone...

  12. A single dose of histamine-receptor antagonists before downhill running alters markers of muscle damage and delayed-onset muscle soreness.

    Science.gov (United States)

    Ely, Matthew R; Romero, Steven A; Sieck, Dylan C; Mangum, Joshua E; Luttrell, Meredith J; Halliwill, John R

    2017-03-01

    Histamine contributes to elevations in skeletal muscle blood flow following exercise, which raises the possibility that histamine is an important mediator of the inflammatory response to exercise. We examined the influence of antihistamines on postexercise blood flow, inflammation, muscle damage, and delayed-onset muscle soreness (DOMS) in a model of moderate exercise-induced muscle damage. Subjects consumed either a combination of fexofenadine and ranitidine (blockade, n = 12) or nothing (control, n = 12) before 45 min of downhill running (-10% grade). Blood flow to the leg was measured before and throughout 120 min of exercise recovery. Markers of inflammation, muscle damage, and DOMS were obtained before and at 0, 6, 12, 24, 48, and 72 h postexercise. At 60 min postexercise, blood flow was reduced ~29% with blockade compared with control ( P histamine-receptor blockade reduced postexercise blood flow, had no effect on the pattern of inflammatory markers, increased serum creatine kinase concentrations, attenuated muscle strength loss, and reduced pain perception following muscle-damaging exercise. NEW & NOTEWORTHY Histamine appears to be intimately involved with skeletal muscle during and following exercise. Blocking histamine's actions during muscle-damaging exercise, via common over-the-counter antihistamines, resulted in increased serum creatine kinase, an indirect marker of muscle damage. Paradoxically, blocking histamine's actions attenuated muscle strength loss and reduced perceptions of muscle pain for 72 h following muscle-damaging exercise. These results indicate that exercise-induced histamine release may have a broad impact on protecting muscle from exercise-induced damage. Copyright © 2017 the American Physiological Society.

  13. Outcome of double vs. single valve replacement for rheumatic heart disease

    International Nuclear Information System (INIS)

    Akhtar, R.P.; Abid, A.R.

    2010-01-01

    To compare the follow-up results of double valve replacement (DVR) i.e. mitral valve replacement (MVR) and aortic valve replacement (AVR) vs. isolated MVR or AVR for rheumatic heart disease. Study Design: An interventional qausi-experimental study. Prospective follow-up of 493 patients with mechanical heart valves was carried out using clinical assessment, international normalized ratio and echocardiography. Patients were divided into three groups: group I having MVR, group II having AVR and group III having DVR. Survival, time and causes of mortality, and frequency of valve thrombosis, haemorrhage and cerebrovascular haemorrhage was noted in the three groups and described as proportions. Actuarial survival was analyzed by Kaplan-Meier method. There were 493 with 287 (58.3%) in group I, 87 (17.6%) in group II and 119 (24.1%) in group III. Total follow-up was 2429.2 patient (pt)-years. Of 77 (15.6%) deaths, 19 (3.8%) were in-hospital and 58 (11.8%) were late. In-hospital mortality was highest 4 (4.6%) in group II followed by 5 (4.2%) group III and 10 (3.5%) group I. Late deaths were 39 (13.4%) in group I, 9 (10.2%) in group II and 10 (8.3%) in group III. The total actuarial survival was 84.4% with survival of 83%, 85.1%, 87.4% in groups I, II and III respectively. On follow-up valve thrombosis occurred in 12 (0.49%/pt-years) patients; 9 (0.67%/pt-years) group I, 1 (0.22%/pt-years) in group II and 2 (0.31%/pt-years) in group III. Severe haemorrhage occurred in 19 (0.78%/pt-years); 14 in (1.04%/pt-years) in group I, 3 (0.66%/pt-years) group II and 2 (0.31%/pt-years) in group III. Cerebrovascular accidents occurred in 34 (1.3%/pt-years); 26 (1.95%/pt-years) in group I and 4 in groups II (0.89%/pt-years) and III (0.62%/pt-years) each. In patients with rheumatic heart disease having combined mitral and aortic valve disease DVR should be performed whenever indicated as it has similar in-hospital mortality and better late survival as compared to isolated aortic or mitral

  14. Type III-IV muscle afferents are not required for steady-state exercise hyperpnea in healthy subjects and patients with COPD or heart failure.

    Science.gov (United States)

    Poon, Chi-Sang; Song, Gang

    2015-09-15

    Blockade of group III-IV muscle afferents by intrathecal injection of the μ-opioid agonist fentanyl (IF) in humans has been variously reported to depress exercise hyperpnea in some studies but not others. A key unanswered question is whether such an effect is transient or persists in the steady state. Here we show that in healthy subjects undergoing constant-load cycling exercise IF significantly slows the transient exercise ventilatory kinetics but has no discernible effect on the ventilatory response when exercise is sufficiently prolonged. Thus, the ventilatory response to group III-IV muscle afferents input in healthy subjects is not a simple reflex but acts like a high-pass filter with maximum sensitivity during early-phase exercise and is reset in the late phase. In patients with chronic heart failure (CHF) IF causes sustained CO2 retention not only during exercise but also in the resting state, where muscle afferents feedback is minimal. In patients with chronic obstructive pulmonary disease (COPD), IF also elicits sustained decreases in the exercise ventilatory response but with little or no resultant CO2 retention due to concomitant decreases in physiological VD/VT (dead space-to-ventilation ratio). These results support the proposition that optimal long-term regulation of exercise hyperpnea in health and in disease is determined centrally by the respiratory controller through the continuing adaptation of an internal model which dynamically tracks the metabolic CO2 load and the ventilatory inefficiency 1/1-VD/VT that must be overcome for the maintenance of arterial PCO2 homeostasis, rather than being reflexively driven by group III-IV muscle afferents feedback per se. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Functional and molecular effects of arginine butyrate and prednisone on muscle and heart in the mdx mouse model of Duchenne Muscular Dystrophy.

    Directory of Open Access Journals (Sweden)

    Alfredo D Guerron

    2010-06-01

    Full Text Available The number of promising therapeutic interventions for Duchenne Muscular Dystrophy (DMD is increasing rapidly. One of the proposed strategies is to use drugs that are known to act by multiple different mechanisms including inducing of homologous fetal form of adult genes, for example utrophin in place of dystrophin.In this study, we have treated mdx mice with arginine butyrate, prednisone, or a combination of arginine butyrate and prednisone for 6 months, beginning at 3 months of age, and have comprehensively evaluated the functional, biochemical, histological, and molecular effects of the treatments in this DMD model. Arginine butyrate treatment improved grip strength and decreased fibrosis in the gastrocnemius muscle, but did not produce significant improvement in muscle and cardiac histology, heart function, behavioral measurements, or serum creatine kinase levels. In contrast, 6 months of chronic continuous prednisone treatment resulted in deterioration in functional, histological, and biochemical measures. Arginine butyrate-treated mice gene expression profiling experiments revealed that several genes that control cell proliferation, growth and differentiation are differentially expressed consistent with its histone deacetylase inhibitory activity when compared to control (saline-treated mdx mice. Prednisone and combination treated groups showed alterations in the expression of genes that control fibrosis, inflammation, myogenesis and atrophy.These data indicate that 6 months treatment with arginine butyrate can produce modest beneficial effects on dystrophic pathology in mdx mice by reducing fibrosis and promoting muscle function while chronic continuous treatment with prednisone showed deleterious effects to skeletal and cardiac muscle. Our results clearly indicate the usefulness of multiple assays systems to monitor both beneficial and toxic effects of drugs with broad range of in vivo activity.

  16. Implantable cardioverter defibrillator therapy in pediatric and congenital heart disease patients: a single tertiary center experience in Korea

    Directory of Open Access Journals (Sweden)

    Bo Kyung Jin

    2013-03-01

    Full Text Available Purpose: The use of implantable cardioverter defibrillators (ICDs to prevent sudden cardiac death is increasing in children and adolescents. This study investigated the use of ICDs in children with congenital heart disease. Methods: This retrospective study was conducted on the clinical characteristics and effectiveness of ICD implantation at the department of pediatrics of a single tertiary center between 2007 and 2011. Results: Fifteen patients underwent ICD implantation. Their mean age at the time of implantation was 14.5±5.4 years (range, 2 to 22 years. The follow-up duration was 28.9±20.4 months. The cause of ICD implantation was cardiac arrest in 7, sustained ventricular tachycardia in 6, and syncope in 2 patients. The underlying disorders were as follows: ionic channelopathy in 6 patients (long QT type 3 in 4, catecholaminergic polymorphic ventricular tachycardia [CPVT] in 1, and J wave syndrome in 1, cardiomyopathy in 5 patients, and postoperative congenital heart disease in 4 patients. ICD coils were implanted in the pericardial space in 2 children (ages 2 and 6 years. Five patients received appropriate ICD shock therapy, and 2 patients received inappropriate shocks due to supraventricular tachycardia.During follow-up, 2 patients required lead dysfunction-related revision. One patient with CPVT suffered from an ICD storm that was resolved using sympathetic denervation surgery. Conclusion: The overall ICD outcome was acceptable in most pediatric patients. Early diagnosis and timely ICD implantation are recommended for preventing sudden death in high-risk children and patients with congenital heart disease.

  17. An anti-NH2-terminal antibody localizes NBCn1 to heart endothelia and skeletal and vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Damkier, Helle Hasager; Nielsen, Søren; Prætorius, Jeppe

    2006-01-01

    The electroneutral sodium bicarbonate cotransporter NBCn1 or NBC3 was originally cloned from rat aorta and from human skeletal muscle. NBCn1 (or NBC3) has been localized to the basolateral membrane of various epithelia, but thus far it has been impossible to detect the protein in these tissues...... and vasculature in skeletal muscle. Analysis of variable NBCn1 splicing by RT-PCR revealed that an NH2-terminal sequence, the cassette III, seems absent from cardiovascular NBCn1 and that both cassettes I and III are variable in most epithelia, whereas cassette II is absent from epithelial NBCn1. Thus...

  18. Screening for coronary artery disease in respiratory patients: comparison of single- and dual-source CT in patients with a heart rate above 70 bpm

    International Nuclear Information System (INIS)

    Pansini, Vittorio; Remy-Jardin, Martine; Tacelli, Nunzia; Faivre, Jean-Baptiste; Remy, Jacques; Flohr, Thomas; Deken, Valerie; Duhamel, Alain

    2008-01-01

    To evaluate the assessibility of coronary arteries in respiratory patients with high heart rates. This study was based on the comparative analysis of two paired populations of 54 patients with a heart rate >70 bpm evaluated with dual-source (group 1) and single-source (group 2) CT. The mean heart rate was 89.1 bpm in group 1 and 86.7 bpm in group 2 (P=0.26). The mean number of assessable segments per patient was significantly higher in group 1 compared to group 2 (P≤0.0001). The proportions of patients in whom proximal and mid-coronary segments were assessable (i.e., the anatomical level enabling screening for asymptomatic coronary artery disease) were 35.3% for heart rates <110 bpm, 35.6% for heart rates <100 bpm, 40% for heart rates <90 bpm, and 60% for heart rates <80 bpm in group 1 and 11.3, 12.2, 8.8, and 10% for the corresponding thresholds in group 2 (P<0.05). In both groups of patients, coronary artery imaging was obtained from standard CT angiograms of the chest. The improvement in coronary imaging with dual-source CT suggests that high heart rates should no longer be considered as contraindications for ECG-gated CT angiograms of the chest whenever clinically relevant. (orig.)

  19. A neuro-mechanical model of a single leg joint highlighting the basic physiological role of fast and slow muscle fibres of an insect muscle system.

    Directory of Open Access Journals (Sweden)

    Tibor Istvan Toth

    Full Text Available In legged animals, the muscle system has a dual function: to produce forces and torques necessary to move the limbs in a systematic way, and to maintain the body in a static position. These two functions are performed by the contribution of specialized motor units, i.e. motoneurons driving sets of specialized muscle fibres. With reference to their overall contraction and metabolic properties they are called fast and slow muscle fibres and can be found ubiquitously in skeletal muscles. Both fibre types are active during stepping, but only the slow ones maintain the posture of the body. From these findings, the general hypothesis on a functional segregation between both fibre types and their neuronal control has arisen. Earlier muscle models did not fully take this aspect into account. They either focused on certain aspects of muscular function or were developed to describe specific behaviours only. By contrast, our neuro-mechanical model is more general as it allows functionally to differentiate between static and dynamic aspects of movement control. It does so by including both muscle fibre types and separate motoneuron drives. Our model helps to gain a deeper insight into how the nervous system might combine neuronal control of locomotion and posture. It predicts that (1 positioning the leg at a specific retraction angle in steady state is most likely due to the extent of recruitment of slow muscle fibres and not to the force developed in the individual fibres of the antagonistic muscles; (2 the fast muscle fibres of antagonistic muscles contract alternately during stepping, while co-contraction of the slow muscle fibres takes place during steady state; (3 there are several possible ways of transition between movement and steady state of the leg achieved by varying the time course of recruitment of the fibres in the participating muscles.

  20. Development of an Assay Based on the Effects of PGBx on the Isolated Perfused Rat Heart and Rat Skeletal Muscle.

    Science.gov (United States)

    1980-09-01

    phosphorylation and enhance ATP synthesis in aged and/or damaqed mitochondria is unique (Polis et al, 1973; Devlin, �), and its lack of effect on the...rat heart, (’An. Pha’mac. 9,101-112. Aronson, C. E. and Serlick, E. R., (1977a) Effects of chlorpromazine on the isola- ted perfused rat heart, ’ Apl...euthyroid and hyperthyroid rats. Eur. J. Pharmac. 19, 12-17. Aronson, C. E. and Serlick, E. R. (1977a) Effects of chlorpromazine on the isolated

  1. The alpha Na-2(+)/K+-ATPase is critical for skeletal and heart muscle function in zebrafish

    DEFF Research Database (Denmark)

    Doganli, Canan; Kjaer-Sorensen, K.; Knoeckel, C.

    2012-01-01

    The Na+/K+-ATPase generates ion gradients across the plasma membrane, essential for multiple cellular functions. In mammals, four different Na+/K+-ATPase alpha-subunit isoforms are associated with characteristic cell-type expression profiles and kinetics. We found the zebrafish alpha Na-2(+)/K...... Na-2(+)/K+-ATPase deficiency reduced the heart rate and caused a loss of left-right asymmetry in the heart tube. Similar phenotypes from knockdown of the Na+/Ca2+ exchanger indicated a role for the interplay between these two proteins in the observed phenotypes. Furthermore, proteomics identified up...

  2. Radiation therapy outcomes in muscle invasive urinary bladder cancer: A single institution experience.

    Science.gov (United States)

    Tiwana, M S; Ni, L H; Saini, S; Verma, S K; Doddamani, D; Jain, N; Biswas, M; Gupta, Meenu; Gupta, Madhur; Saini, M; Chauhan, N

    2016-01-01

    To audit the survival outcomes and loco-regional control in muscle invasive urinary bladder cancer patients treated with external beam radiation therapy (RT). From November 2008 through December 2011, 50 consecutively diagnosed muscle invasive urinary bladder carcinoma (T2-4a N0-2, M0) patients were included in this retrospective study. All these patients received external beam RT to a median dose of 60 Gy (range 30-66 Gy), and were not suitable for radical surgery due to patients' preference or medical comorbidities. A stepwise procedure using proportional hazard regression was used to identify prognostic factors with respect to survival. Completion trans-urethral resection of bladder tumor was done in 38 (76%) patients of the cohort and 47 (94%) had transitional cell carcinoma on histopathology. Clinical stage T2 was diagnosed in 40 (80%) patients. The median follow-up for the entire cohort was 14 ± 8.9 months (range 1-36 months). In conclusion, 24 patients (48%) were free of disease, 5 patients (10%) had residual disease, and 13 patients (26%) had died of disease. Two-year and 3 year overall survival of intact bladder for the entire cohort was 58% and 43.6%, respectively. Cox regression modeling strongly suggested clinical stage (P = 0.01) and RT dose (P = 0.001) as being predictors for overall survival. RT shows reliable outcomes and excellent compliance in this advanced disease. Prescribing a higher RT dose could potentially correlate to better intact bladder control rates while maintaining good quality of life in selected patients.

  3. An anti-NH2-terminal antibody localizes NBCn1 to heart endothelia and skeletal and vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Damkier, Helle Hasager; Nielsen, Søren; Prætorius, Jeppe

    2006-01-01

    The electroneutral sodium bicarbonate cotransporter NBCn1 or NBC3 was originally cloned from rat aorta and from human skeletal muscle. NBCn1 (or NBC3) has been localized to the basolateral membrane of various epithelia, but thus far it has been impossible to detect the protein in these tissues...

  4. Lion (Panthera leo) and caracal (Caracal caracal) type IIx single muscle fibre force and power exceed that of trained humans.

    Science.gov (United States)

    Kohn, Tertius A; Noakes, Timothy D

    2013-03-15

    This study investigated for the first time maximum force production, shortening velocity (Vmax) and power output in permeabilised single muscle fibres at 12°C from lion, Panthera leo (Linnaeus 1758), and caracal, Caracal caracal (Schreber 1776), and compared the values with those from human cyclists. Additionally, the use and validation of previously frozen tissue for contractile experiments is reported. Only type IIx muscle fibres were identified in the caracal sample, whereas type IIx and only two type I fibres were found in the lion sample. Only pure type I and IIa, and hybrid type IIax fibres were identified in the human samples - there were no pure type IIx fibres. Nevertheless, compared with all the human fibre types, the lion and caracal fibres were smaller (Plion: 3008±151 μm(2), caracal: 2583±221 μm(2)). On average, the felid type IIx fibres produced significantly greater force (191-211 kN m(-2)) and ~3 times more power (29.0-30.3 kN m(-2) fibre lengths s(-1)) than the human IIax fibres (100-150 kN m(-2), 4-11 kN m(-2) fibre lengths s(-1)). Vmax values of the lion type IIx fibres were also higher than those of human type IIax fibres. The findings suggest that the same fibre type may differ substantially between species and potential explanations are discussed.

  5. Gene expression changes of single skeletal muscle fibers in response to modulation of the mitochondrial calcium uniporter (MCU

    Directory of Open Access Journals (Sweden)

    Francesco Chemello

    2015-09-01

    Full Text Available The mitochondrial calcium uniporter (MCU gene codifies for the inner mitochondrial membrane (IMM channel responsible for mitochondrial Ca2+ uptake. Cytosolic Ca2+ transients are involved in sarcomere contraction through cycles of release and storage in the sarcoplasmic reticulum. In addition cytosolic Ca2+ regulates various signaling cascades that eventually lead to gene expression reprogramming. Mitochondria are strategically placed in close contact with the ER/SR, thus cytosolic Ca2+ transients elicit large increases in the [Ca2+] of the mitochondrial matrix ([Ca2+]mt. Mitochondrial Ca2+ uptake regulates energy production and cell survival. In addition, we recently showed that MCU-dependent mitochondrial Ca2+ uptake controls skeletal muscle trophism. In the same report, we dissected the effects of MCU-dependent mitochondrial Ca2+ uptake on gene expression through microarray gene expression analysis upon modulation of MCU expression by in vivo AAV infection. Analyses were performed on single skeletal muscle fibers at two time points (7 and 14 days post-AAV injection. Raw and normalized data are available on the GEO database (http://www.ncbi.nlm.nih.gov/geo/ (GSE60931.

  6. Label-Free LC-MS Profiling of Skeletal Muscle Reveals Heart-Type Fatty Acid Binding Protein as a Candidate Biomarker of Aerobic Capacity

    Directory of Open Access Journals (Sweden)

    Zulezwan A. Malik

    2013-12-01

    Full Text Available Two-dimensional gel electrophoresis provides robust comparative analysis of skeletal muscle, but this technique is laborious and limited by its inability to resolve all proteins. In contrast, orthogonal separation by SDS-PAGE and reverse-phase liquid chromatography (RPLC coupled to mass spectrometry (MS affords deep mining of the muscle proteome, but differential analysis between samples is challenging due to the greater level of fractionation and the complexities of quantifying proteins based on the abundances of their tryptic peptides. Here we report simple, semi-automated and time efficient (i.e., 3 h per sample proteome profiling of skeletal muscle by 1-dimensional RPLC electrospray ionisation tandem MS. Solei were analysed from rats (n = 5, in each group bred as either high- or low-capacity runners (HCR and LCR, respectively that exhibited a 6.4-fold difference (1,625 ± 112 m vs. 252 ± 43 m, p < 0.0001 in running capacity during a standardized treadmill test. Soluble muscle proteins were extracted, digested with trypsin and individual biological replicates (50 ng of tryptic peptides subjected to LC-MS profiling. Proteins were identified by triplicate LC-MS/MS analysis of a pooled sample of each biological replicate. Differential expression profiling was performed on relative abundances (RA of parent ions, which spanned three orders of magnitude. In total, 207 proteins were analysed, which encompassed almost all enzymes of the major metabolic pathways in skeletal muscle. The most abundant protein detected was type I myosin heavy chain (RA = 5,843 ± 897 and the least abundant protein detected was heat shock 70 kDa protein (RA = 2 ± 0.5. Sixteen proteins were significantly (p < 0.05 more abundant in HCR muscle and hierarchal clustering of the profiling data highlighted two protein subgroups, which encompassed proteins associated with either the respiratory chain or fatty acid oxidation. Heart-type fatty acid binding protein (FABPH was 1

  7. Four days of muscle disuse impairs single fiber contractile function in young and old healthy men

    DEFF Research Database (Denmark)

    Hvid, Lars G; Suetta, Charlotte; Aagaard, Per

    2013-01-01

    The purpose of the study was to investigate the effects of 4days of disuse (knee brace) on contractile function of isolated vastus lateralis fibers (n=486) from 11 young (24.3±0.9yrs) and 11 old (67.2±1.0yrs) healthy men having comparable levels of physical activity. Prior to disuse single fiber...

  8. The equivalent circuit of single crab muscle fibers as determined by impedance measurements with intracellular electrodes.

    Science.gov (United States)

    Eisenberg, R S

    1967-07-01

    The input impedance of muscle fibers of the crab was determined with microelectrodes over the frequency range 1 cps to 10 kc/sec. Care was taken to analyze, reduce, and correct for capacitive artifact. One dimensional cable theory was used to determine the properties of the equivalent circuit of the membrane admittance, and the errors introduced by the neglect of the three dimensional spread of current are discussed. In seven fibers the equivalent circuit of an element of the membrane admittance must contain a DC path and two capacitances, each in series with a resistance. In two fibers, the element of membrane admittance could be described by one capacitance in parallel with a resistance. In several fibers there was evidence for a third very large capacitance. The values of the elements of the equivalent circuit depend on which of several equivalent circuits is chosen. The circuit (with a minimum number of elements) that was considered most reasonably consistent with the anatomy of the fiber has two branches in parallel: one branch having a resistance R(e) in series with a capacitance C(e); the other branch having a resistance R(b) in series with a parallel combination of a resistance R(m) and a capacitance C(m). The average circuit values (seven fibers) for this model, treating the fiber as a cylinder of sarcolemma without infoldings or tubular invaginations, are R(e) = 21 ohm cm(2); C(e) = 47 microf/cm(2); R(b) = 10.2 ohm cm(2); R(m) = 173 ohm cm(2); C(m) = 9.0 microf/cm(2). The relation of this equivalent circuit and another with a nonminimum number of circuit elements to the fine structure of crab muscle is discussed. In the above equivalent circuit R(m) and C(m) are attributed to the sarcolemma; R(e) and C(e), to the sarcotubular system; and R(b), to the amorphous material found around crab fibers. Estimates of actual surface area of the sarcolemma and sarcotubular system permit the average circuit values to be expressed in terms of unit membrane area. The

  9. Effect of Feedback Corrective Exercise on Knee Valgus and Electromyographic Activity of Lower Limb Muscles in Single Leg Squat

    Directory of Open Access Journals (Sweden)

    Negar Koorosh-fard

    2015-07-01

    Full Text Available Objective: The aim of this study was assessing the effect of feedback correcting exercise in front of mirror during running on frontal plane knee and pelvic kinematic and electromyography activity of some lower extremity muscles in single leg squat (SLS. Materials & Methods: This study was quasi experimental. 23 active female subjects participated in two experimental and control groups with mean age (21.86± 2.43 years .experimental group contains subjects with knee valgus and pelvic drop angle more than a mean plus one standard deviation of the population in functional SLS. Muscular activity (RMS of gluteus maximus, Gluteus medius, rectus femoris, vastus medialis, vastus lateralis, biceps femoris and semitendinosus, angle of knee valgus and pelvic drop were register in end of SLS Pre and post of 8 training sessions. Comparing Variable has done with independent t statistical test between 2 groups and pair sample t test within each groups with significant level of 0.05. Results: Statistical analysis Before training showed no significant differences in pelvic drop between two groups (P&ge0.05, but knee valgus angle was significantly more than control group (P&le0.05. In spit that most muscle activities (% MVC except biceps femoris (P&le0.05, were greater in experimental group, no significant difference (P&ge0.05 has seen in two groups. Comparing pre and post test has showed no significant difference in knee valgus of experimental group, however it decreased around 2 degrees and although %MVC decreased in all muscles, just rectuse femoris has shown significant difference (P&le0.05. No significant difference has seen in control group in all variables (P&ge0.05. Conclusion: Findings showed poor neuromuscular control in experimental group which improved to some extent after training because lower muscle activity and energy consumption in specific movement with similar kinematic indicate improvement of motor control or cause learning. It seems that

  10. Effect of methylglyoxal bis(guanylhydrazone) on hepatic, heart and skeletal muscle mitochrondrial carnitine palmitoyltransferase and. beta. -oxidation of fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Brady, L.J.; Brady, P.S.; Gandour, R.D.

    1986-05-01

    Methylglyoxal bis(guanylhydrazone) (MGBG) is an antileukemic agent and polyamine analog which inhibits S-adenosyl methionine decarboxylase. However, MGBG also produces mitochondrial structural damage and inhibition of ..beta..-oxidation. The present experiments were designed to determine if MGBG acts via carnitine palmitoyltransferase-A (CPT-A) inhibition. Liver, heart and skeletal muscle mitochondria were isolated from rats following a 24 h fast. MGBG was competitive with 1-carnitine. The MGBG CPT-A Ki were (mM): liver, 5.0 +/- 0.6 (n = 15); heart, 3.2 +/- 1.2 (n = 3); skeletal muscle, 2.8 +/- 1.0 (n = 3). Lysis of hepatic mitochondria with Triton X-100 yielded a Ki of 4.0 +/- 2.0. Purified hepatic CPT was also sensitive to MGBG inhibition (Ki = 4.5 mM). Spermine and spermidine, which are structurally similar to MGBG, did not inhibit CPT or acid-soluble product formation from 1-(/sup 14/C)-palmitoyl-CoA. MGBG inhibited mitochondrial state 3 oxidation rates of palmitoyl-CoA and palmitoylcarnitine, as well as of glutamate. However, the fatty acid substrates were considerably more sensitive than glutamate to MGBG inhibition. MGBG also increased hepatic mitochondrial aggregation which was reversed by 1-carnitine. Fluorescence polarization, using diphenylhexatriene as a probe, indicated that MGBG increased membrane rigidity in a dose dependent manner. This effect was not reversed by 1-carnitine. The authors conclude that MGBG exhibits competitive competition with 1-carnitine for CPT. However, MGBG also exhibits a number of effects which may be mediated through membrane interaction and which are not necessarily reversed by carnitine.

  11. Effect of methylglyoxal bis(guanylhydrazone) on hepatic, heart and skeletal muscle mitochrondrial carnitine palmitoyltransferase and β-oxidation of fatty acids

    International Nuclear Information System (INIS)

    Brady, L.J.; Brady, P.S.; Gandour, R.D.

    1986-01-01

    Methylglyoxal bis(guanylhydrazone) (MGBG) is an antileukemic agent and polyamine analog which inhibits S-adenosyl methionine decarboxylase. However, MGBG also produces mitochondrial structural damage and inhibition of β-oxidation. The present experiments were designed to determine if MGBG acts via carnitine palmitoyltransferase-A (CPT-A) inhibition. Liver, heart and skeletal muscle mitochondria were isolated from rats following a 24 h fast. MGBG was competitive with 1-carnitine. The MGBG CPT-A Ki were (mM): liver, 5.0 +/- 0.6 (n = 15); heart, 3.2 +/- 1.2 (n = 3); skeletal muscle, 2.8 +/- 1.0 (n = 3). Lysis of hepatic mitochondria with Triton X-100 yielded a Ki of 4.0 +/- 2.0. Purified hepatic CPT was also sensitive to MGBG inhibition (Ki = 4.5 mM). Spermine and spermidine, which are structurally similar to MGBG, did not inhibit CPT or acid-soluble product formation from 1-[ 14 C]-palmitoyl-CoA. MGBG inhibited mitochondrial state 3 oxidation rates of palmitoyl-CoA and palmitoylcarnitine, as well as of glutamate. However, the fatty acid substrates were considerably more sensitive than glutamate to MGBG inhibition. MGBG also increased hepatic mitochondrial aggregation which was reversed by 1-carnitine. Fluorescence polarization, using diphenylhexatriene as a probe, indicated that MGBG increased membrane rigidity in a dose dependent manner. This effect was not reversed by 1-carnitine. The authors conclude that MGBG exhibits competitive competition with 1-carnitine for CPT. However, MGBG also exhibits a number of effects which may be mediated through membrane interaction and which are not necessarily reversed by carnitine

  12. Relationship of Physical Function to Single Muscle Fiber Contractility in Older Adults: Effects of Resistance Training with and without Caloric Restriction.

    Science.gov (United States)

    Wang, Zhong-Min; Leng, Xiaoyan; Messi, María Laura; Choi, Seung J; Marsh, Anthony P; Nicklas, Barbara; Delbono, Osvaldo

    2018-03-13

    Previous studies support beneficial effects of both resistance exercise training (RT) and caloric restriction (CR) on skeletal muscle strength and physical performance. The goal of this study was to determine the effects of adding CR to RT on single-muscle fiber contractility responses to RT in older overweight and obese adults. We analyzed contractile properties in 1,253 single myofiber from muscle biopsies of the vastus lateralis, as well as physical performance and thigh muscle volume, in 31 older (65-80 yrs), overweight or obese (body mass index= 27-35 kg/m2) men (n=19) and women (n=12) who were randomly assigned to a standardized, progressive RT intervention with CR (RT+CR; n=15) or without CR (RT; n=16) for 5 months. Both interventions evoked an increase in force normalized to CSA, in type-I and type-II fibers and knee extensor quality. However, these improvements were not different between intervention groups. In the RT group, changes in total thigh fat volume inversely correlated with changes in type-II fiber force (r = -0.691; p=0.019). Within the RT+CR group, changes in gait speed correlated positively with changes in type-I fiber CSA (r=0.561; p=0.030). In addition, increases in type-I normalized fiber force were related to decreases in thigh intermuscular fat volume (r= -0.539; p= 0.038). Single muscle fiber force and knee extensor quality improve with RT and RT+CR; however, CR does not enhance improvements in single muscle fiber contractility or whole muscle in response to RT in older overweight and obese men and women.

  13. Sirolimus as an alternative to anticalcineurin therapy in heart transplantation: experience of a single center.

    Science.gov (United States)

    Fernandez-Valls, M; Gonzalez-Vilchez, F; de Prada, J A Vazquez; Ruano, J; Ruisanchez, C; Martin-Duran, R

    2005-11-01

    We report a series of 26 heart transplant recipients with renal impairment in which sirolimus was used as the basic immunosuppresive drug (without associated calcineurin inhibitors) to avoid further nephrotoxicity. Sirolimus (trough levels 10 to 12 ng/mL, average daily dose 3 mg) was used in two settings: de novo in 7 patients with significant preexistent renal impairment and as a chronic conversion in 19 stable patients with established renal failure (creatinine level >2 mg/dL). In all de novo patients (n = 7), the renal function significantly improved. Creatinine fell from 2.95 +/- 0.9 mg/dL to 1.41 +/- 0.4 mg/dL at follow-up (P = .0017). One patient died suddenly of a massive pulmonary embolism. Only one patient experienced histologic but reversible rejection. In one patient, anemia and diarrhea prompted sirolimus withdrawal. Five patients had infectious episodes: three bacterial pneumonias, one mediastinitis, and two CMV infections. In the chronic conversion group (n = 19), the improvement was mostly limited to patients with moderate renal failure (creatinine < or =2.5 mg/dL) in which creatinine fell from 2.24 +/- 0.2 to 1.9 +/- 0.27 mg/dL, P = .009). When basal creatinine was over 2.5 mg/dL, only one third of the patients improved after conversion. Two patients died: terminal renal failure and cerebrovascular accident. There were no clinical episodes of rejection. Secondary effects prompted the discontinuation of sirolimus in five patients: two definite and one possible interstitial pneumonitis and two cases of anemia). The symptoms resolved after sirolimus withdrawal. Six patients had infection: four pneumonias, one sepsis, and one cutaneous abscess. Sirolimus is an interesting alternative to calcineurin inhibitors in selected patients with renal impairment. It prevents renal failure in de novo recipients at high risk of catastrophic renal damage and ameliorates renal dysfunction in chronic patients with moderate renal dysfunction. Given the high incidence of

  14. Single-Center Experience With HeartMate II Left Ventricular Assist Device Explantation.

    Science.gov (United States)

    Tchantchaleishvili, Vakhtang; Cheyne, Christina; Sherazi, Saadia; Melvin, Amber L; Hallinan, William; Chen, Leway; Todd Massey, Howard

    2016-12-01

    In patients with continuous flow left ventricular assist devices (CF-LVADs) myocardial recovery is uncommon. Given the heterogeneity of the population implanted and low incidence of recovery, the discovery of native left ventricular (LV) recovery and criteria for explantation of CF-LVAD system is not clearly determined. We sought to analyze the characteristics of the patients who underwent CF-LVAD explantation at our institution. Prospectively collected data on patients supported with CF-LVADs were reviewed retrospectively. Patients who underwent CF-LVAD explants were identified and their characteristics were analyzed with a focus on patient presentation and determinants of explantability. From November 2006 to June 2014, 223 patients (181 male, 42 female) underwent implantation of HeartMate II LVAD. Seven female (16.7%) and one male (0.6%) patients were explanted (P < 0.001). Mean age was 43 ± 9 years and etiology for cardiomyopathy was ischemic in three (37.5%) patients, nonischemic in four (50%) patients, and mixed in the one (12.5%) male patient of the cohort. Five (62.5%) patients presented acutely with significant hemolysis, and were found to have LV improvement as well as reduced, absent, or reversed diastolic flow velocities on echocardiography. Overall, mean lactate dehydrogenase level before explantation was 1709 ± 1168 U/L compared to the mean baseline level of 601 ± 316 U/L (P = 0.048). Mean LV ejection fraction (LVEF) improved from 17 ± 7% preimplant to 56 ± 11% pre-explantation (P < 0.001). Median number of days on CF-LVAD support was 870 (interquartile range, 209-975) while mean duration of follow-up after the CF-LVAD explantation was 276 ± 240 days. Mean LVEF dropped from 46 ± 19% postexplantation to 34 ± 10% during the most recent follow-up (P = 0.015). At our institution, patients who underwent LVAD explants were predominantly women with nonischemic cardiomyopathy. Clinical evidence of

  15. Lower extremity muscle activation onset times during the transition from double-leg stance to single-leg stance in anterior cruciate ligament reconstructed subjects.

    Science.gov (United States)

    Dingenen, Bart; Janssens, Luc; Claes, Steven; Bellemans, Johan; Staes, Filip F

    2016-06-01

    Previous studies mainly focused on muscles at the operated knee after anterior cruciate ligament reconstruction, less on muscles around other joints of the operated and non-operated leg. The aim of this study was to investigate muscle activation onset times during the transition from double-leg stance to single-leg stance in anterior cruciate ligament reconstructed subjects. Lower extremity muscle activation onset times of both legs of 20 fully returned to sport anterior cruciate ligament reconstructed subjects and 20 non-injured control subjects were measured during the transition from double-leg stance to single-leg stance in eyes open and eyes closed conditions. Analysis of covariance (ANCOVA) was used to evaluate differences between groups and differences between legs within both groups, while controlling for peak center of pressure velocity. Significantly delayed muscle activation onset times were found in the anterior cruciate ligament reconstructed group compared to the control group for gluteus maximus, gluteus medius, vastus medialis obliquus, medial hamstrings, lateral hamstrings and gastrocnemius in both eyes open and eyes closed conditions (Panterior cruciate ligament reconstructed group, no significant different muscle activation onset times were found between the operated and non-operated leg (P>.05). Despite completion of rehabilitation and full return to sport, the anterior cruciate ligament reconstructed group showed neuromuscular control deficits that were not limited to the operated knee joint. Clinicians should focus on relearning multi-segmental anticipatory neuromuscular control strategies after anterior cruciate ligament reconstruction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Effects of low-level laser therapy (LLLT) and diclofenac (topical and intramuscular) as single and combined therapy in experimental model of controlled muscle strain in rats.

    Science.gov (United States)

    de Paiva Carvalho, Rodrigo Leal; Leal-Junior, Ernesto Cesar Pinto; Petrellis, Maria Carla; Marcos, Rodrigo Labat; de Carvalho, Maria Helena Catelli; De Nucci, Gilberto; Lopes-Martins, Rodrigo Alvaro Brandão

    2013-01-01

    Muscle injuries represent ca 30% of sports injuries and excessive stretching of muscle causes more than 90% of injuries. Currently the most used treatments are nonsteroidal anti-inflammatory drugs (NSAIDs), however, in last years, low-level laser therapy (LLLT) is becoming an interesting therapeutic modality. The aim of this study was to evaluate the effect of single and combined therapies (LLLT, topical application of diclofenac and intramuscular diclofenac) on functional and biochemical aspects in an experimental model of controlled muscle strain in rats. Muscle strain was induced by overloading tibialis anterior muscle of rats. Injured groups received either no treatment, or a single treatment with topical or intramuscular diclofenac (TD and ID), or LLLT (3 J, 810 nm, 100 mW) 1 h after injury. Walking track analysis was the functional outcome and biochemical analyses included mRNA expression of COX-1 and COX-2 and blood levels of prostaglandin E2 (PGE2 ). All treatments significantly decreased COX-1 and COX-2 gene expression compared with injury group (P < 0.05). However, LLLT showed better effects than TD and ID regarding PGE2 levels and walking track analysis (P < 0.05). We can conclude that LLLT has more efficacy than topical and intramuscular diclofenac in treatment of muscle strain injury in acute stage. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  17. The Effect of Intelligence, Leg Muscle Strength, and Balance Towards The Learning Outcomes of Pencak Silat with Empty-Handed Single Artistic

    Directory of Open Access Journals (Sweden)

    Aridhotul Haqiyah

    2017-10-01

    Full Text Available This study aims to Determine the effect of intelligence, leg muscle strength, as well as the balance towards the learning outcomes of pencak silat empty-handed single artistic on the Physical Education students of Islamic University 45 Bekasi. The research method is a survey, and the analysis technique is path analysis. This research held in Islamic University 45 Bekasi with 122 people of population. The sampling technique used is random sampling, then a sample of this research is 60 people. The instruments used are a rubric 4 scale (very good, good, enough and less of the learning outcomes of pencak silat emptyhanded single artistic, intelligence test with IST (Intelligent Structure Test, leg muscle strength with instrument squat test, and test of balance by using the modified bass test of dynamic balance. Based the result of the data processing and analysis, the Conclusions are: : (1 Intelligence directly effect on the learningoutcomes of pencak silat empty-handed single artistic with ρy1  = 0.359, (2 Leg muscles strength directlyeffect on the learning outcomes of pencak silat empty-handed single artistic with ρy2 = 0.228, (3 Balance directly effect on the learning outcomes of pencak silat empty-handed single artistic with ρy3 = 0.356, (4 Intelligence directly effects on the balance with ρ31 = 0.662, and (5 Leg muscle strength directly effectson the balance with ρ32 = 0.298.

  18. Inspiratory Muscle Training and Functional Electrical Stimulation for Treatment of Heart Failure With Preserved Ejection Fraction: The TRAINING-HF Trial.

    Science.gov (United States)

    Palau, Patricia; Domínguez, Eloy; López, Laura; Ramón, José María; Heredia, Raquel; González, Jessika; Santas, Enrique; Bodí, Vicent; Miñana, Gema; Valero, Ernesto; Mollar, Anna; Bertomeu González, Vicente; Chorro, Francisco J; Sanchis, Juan; Lupón, Josep; Bayés-Genís, Antoni; Núñez, Julio

    2018-03-16

    Despite the prevalence of heart failure with preserved ejection fraction (HFpEF), there is currently no evidence-based effective therapy for this disease. This study sought to evaluate whether inspiratory muscle training (IMT), functional electrical stimulation (FES), or a combination of both (IMT + FES) improves 12- and 24-week exercise capacity as well as left ventricular diastolic function, biomarker profile, and quality of life in HFpEF. A total of 61 stable symptomatic patients (New York Heart Association II-III) with HFpEF were randomized (1:1:1:1) to receive a 12-week program of IMT, FES, or IMT + FES vs usual care. The primary endpoint of the study was to evaluate change in peak exercise oxygen uptake at 12 and 24 weeks. Secondary endpoints were changes in quality of life, echocardiogram parameters, and prognostic biomarkers. We used a mixed-effects model for repeated-measures to compare endpoints changes. Mean age and peak exercise oxygen uptake were 74 ± 9 years and 9.9 ± 2.5mL/min/kg, respectively. The proportion of women was 58%. At 12 weeks, the mean increase in peak exercise oxygen uptake (mL/kg/min) compared with usual care was 2.98, 2.93, and 2.47 for IMT, FES, and IMT + FES, respectively (P de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  19. Single-walled carbon nanotubes based chemiresistive genosensor for label-free detection of human rheumatic heart disease

    International Nuclear Information System (INIS)

    Singh, Swati; Kumar, Ashok; Khare, Shashi; Mulchandani, Ashok; Rajesh

    2014-01-01

    A specific and ultrasensitive, label free single-walled carbon nanotubes (SWNTs) based chemiresistive genosensor was fabricated for the early detection of Streptococcus pyogenes infection in human causing rheumatic heart disease. The mga gene of S. pyogenes specific 24 mer ssDNA probe was covalently immobilized on SWNT through a molecular bilinker, 1-pyrenemethylamine, using carbodiimide coupling reaction. The sensor was characterized by the current-voltage (I-V) characteristic curve and scanning electron microscopy. The sensing performance of the sensor was studied with respect to changes in conductance in SWNT channel based on hybridization of the target S. pyogenes single stranded genomic DNA (ssG-DNA) to its complementary 24 mer ssDNA probe. The sensor shows negligible response to non-complementary Staphylococcus aureus ssG-DNA, confirming the specificity of the sensor only with S. pyogenes. The genosensor exhibited a linear response to S. pyogenes G-DNA from 1 to1000 ng ml −1 with a limit of detection of 0.16 ng ml −1

  20. Single-walled carbon nanotubes based chemiresistive genosensor for label-free detection of human rheumatic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Swati; Kumar, Ashok, E-mail: rajesh-csir@yahoo.com, E-mail: ashokigib@rediffmail.com [CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007 (India); Academy of Scientific and Innovative Research (AcSIR), New Delhi (India); Khare, Shashi [National Centre for Disease Control, Sham Nath Marg, Delhi 110054 (India); Mulchandani, Ashok [Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521 (United States); Rajesh, E-mail: rajesh-csir@yahoo.com, E-mail: ashokigib@rediffmail.com [CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi 110012 (India)

    2014-11-24

    A specific and ultrasensitive, label free single-walled carbon nanotubes (SWNTs) based chemiresistive genosensor was fabricated for the early detection of Streptococcus pyogenes infection in human causing rheumatic heart disease. The mga gene of S. pyogenes specific 24 mer ssDNA probe was covalently immobilized on SWNT through a molecular bilinker, 1-pyrenemethylamine, using carbodiimide coupling reaction. The sensor was characterized by the current-voltage (I-V) characteristic curve and scanning electron microscopy. The sensing performance of the sensor was studied with respect to changes in conductance in SWNT channel based on hybridization of the target S. pyogenes single stranded genomic DNA (ssG-DNA) to its complementary 24 mer ssDNA probe. The sensor shows negligible response to non-complementary Staphylococcus aureus ssG-DNA, confirming the specificity of the sensor only with S. pyogenes. The genosensor exhibited a linear response to S. pyogenes G-DNA from 1 to1000 ng ml{sup −1} with a limit of detection of 0.16 ng ml{sup −1}.

  1. Highly wearable cuff-less blood pressure and heart rate monitoring with single-arm electrocardiogram and photoplethysmogram signals.

    Science.gov (United States)

    Zhang, Qingxue; Zhou, Dian; Zeng, Xuan

    2017-02-06

    Long-term continuous systolic blood pressure (SBP) and heart rate (HR) monitors are of tremendous value to medical (cardiovascular, circulatory and cerebrovascular management), wellness (emotional and stress tracking) and fitness (performance monitoring) applications, but face several major impediments, such as poor wearability, lack of widely accepted robust SBP models and insufficient proofing of the generalization ability of calibrated models. This paper proposes a wearable cuff-less electrocardiography (ECG) and photoplethysmogram (PPG)-based SBP and HR monitoring system and many efforts are made focusing on above challenges. Firstly, both ECG/PPG sensors are integrated into a single-arm band to provide a super wearability. A highly convenient but challenging single-lead configuration is proposed for weak single-arm-ECG acquisition, instead of placing the electrodes on the chest, or two wrists. Secondly, to identify heartbeats and estimate HR from the motion artifacts-sensitive weak arm-ECG, a machine learning-enabled framework is applied. Then ECG-PPG heartbeat pairs are determined for pulse transit time (PTT) measurement. Thirdly, a PTT&HR-SBP model is applied for SBP estimation, which is also compared with many PTT-SBP models to demonstrate the necessity to introduce HR information in model establishment. Fourthly, the fitted SBP models are further evaluated on the unseen data to illustrate the generalization ability. A customized hardware prototype was established and a dataset collected from ten volunteers was acquired to evaluate the proof-of-concept system. The semi-customized prototype successfully acquired from the left upper arm the PPG signal, and the weak ECG signal, the amplitude of which is only around 10% of that of the chest-ECG. The HR estimation has a mean absolute error (MAE) and a root mean square error (RMSE) of only 0.21 and 1.20 beats per min, respectively. Through the comparative analysis, the PTT&HR-SBP models significantly outperform

  2. Comparison of Abdominal Muscle Activity During a Single-Legged Hold in the Hook-Lying Position on the Floor and on a Round Foam Roll

    Science.gov (United States)

    Kim, Su-Jung; Kwon, Oh-Yun; Yi, Chung-Hwi; Jeon, Hye-Seon; Oh, Jae-Seop; Cynn, Heon-Seock; Weon, Jong-Hyuck

    2011-01-01

    Context: To improve trunk stability or trunk muscle strength, many athletic trainers and physiotherapists use various types of unstable equipment for training. The round foam roll is one of those unstable pieces of equipment and may be useful for improving trunk stability. Objective: To assess the effect of the supporting surface (floor versus round foam roll) on the activity of abdominal muscles during a single-legged hold exercise performed in the hook-lying position on the floor and on a round foam roll. Design: Crossover study. Setting: University research laboratory. Patients or Other Participants: Nineteen healthy volunteers (11 men, 8 women) from a university population. Interventions : The participants were instructed to perform a single-legged hold exercise while in the hook-lying position on the floor (stable surface) and on a round foam roll (unstable surface). Main Outcome Measure(s): Surface electromyography (EMG) signals were recorded from the bilateral rectus abdominis, internal oblique, and external oblique muscles. Dependent variables were examined with a paired t test. Results: The EMG activities in all abdominal muscles were greater during the single-legged hold exercise performed on the round foam roll than on the stable surface. Conclusions: The single-legged hold exercise in the hook-lying position on an unstable supporting surface induced greater abdominal muscle EMG amplitude than the same exercise performed on a stable supporting surface. These results suggest that performing the single-legged hold exercise while in the hook-lying position on a round foam roll is useful for activating the abdominal muscles. PMID:21944072

  3. Chemoradiotherapy for muscle invading bladder carcinoma. final report of a single institutional organ-sparing program

    International Nuclear Information System (INIS)

    Arias, Fernando; Dominguez, Miguel A.; Martinez, Enrique; Illarramendi, Jose J.; Miquelez, Santiago; Pascual, Ignacio; Marcos, Marta

    2000-01-01

    Purpose: Chemoradiotherapy is becoming an alternative to radical cystectomy among patients with muscle invading bladder cancer. We began a prospective study in 1988 to determine the possibilities of conservative treatment and aiming to improve the results obtained by cystectomy alone in invasive bladder cancer. A combination of methotrexate, vinblastine, adriamycin, and cisplatin (M-VAC), followed by radiotherapy and concomitant cisplatin was used. Methods: Fifty patients with good performance status and with stages T2 to T4 operable untreated invasive bladder cancer were entered in the study. Treatment protocol was as follows: (i) cytoreductive transurethral resection; (ii) two cycles of M-VAC chemotherapy; (iii) radiotherapy, 45 Gy on pelvic volume and, at the same time, 20 mg/m 2 cisplatin on days 1 to 5. Cystoscopic evaluation: if there was a complete response, radiotherapy was completed up to 65 Gy; if there was not a complete response, a cystectomy was performed. Median follow-up of the series was 73 months (18-180 m). Results: Tumor response was as follows: 34 complete responses (68%), 9 partial responses (18%), and 7 nonresponses (14%) were observed. The 5-year overall survival and local control were 48% and 47%, respectively. For the complete responder patient, 5-year survival and local control were 65% and 70%, respectively. Severe toxicity was uncommon. The most frequent were leucopenia and cystitis. No treatment-related deaths occurred with either treatment protocol. Conclusions: Conservative combination treatment may be an acceptable alternative to immediate cystectomy in selected patients with bladder cancer, although a randomized clinical trial would be required to produce definitive results

  4. Muscle Fibre Types, Ubiquinone Content and Exercise Capacity in Hypertension and Effort Angina

    DEFF Research Database (Denmark)

    Karlsson, Jan; Diamant, Bertil; Folkers, Karl

    1991-01-01

    Farmakologi, hypertension, IHD, skeletal muscle fibre composition, muscle coenzyme Q10, ischaemic heart disease, effort angina, muscle fibre lesion, muscle ubiquinone......Farmakologi, hypertension, IHD, skeletal muscle fibre composition, muscle coenzyme Q10, ischaemic heart disease, effort angina, muscle fibre lesion, muscle ubiquinone...

  5. Gold nanoparticles administration induces disarray of heart muscle, hemorrhagic, chronic inflammatory cells infiltrated by small lymphocytes, cytoplasmic vacuolization and congested and dilated blood vessels

    Directory of Open Access Journals (Sweden)

    Abdelhalim Mohamed Anwar K

    2011-12-01

    Full Text Available Abstract Background Despite significant research efforts on cancer therapy, diagnostics and imaging, many challenges remain unsolved. There are many unknown details regarding the interaction of nanoparticles (NPs and biological systems. The structure and properties of gold nanoparticles (GNPs make them useful for a wide array of biological applications. However, for the application of GNPs in therapy and drug delivery, knowledge regarding their bioaccumulation and associated local or systemic toxicity is necessary. Information on the biological fate of NPs, including distribution, accumulation, metabolism, and organ specific toxicity is still minimal. Studies specifically dealing with the toxicity of NPs are rare. The aim of the present study was to investigate the effects of intraperitoneal administration of GNPs on histological alterations of the heart tissue of rats in an attempt to identify and understand the toxicity and the potential role of GNPs as a therapeutic and diagnostic tool. Methods A total of 40 healthy male Wistar-Kyoto rats received 50 μl infusions of 10, 20 and 50 nm GNPs for 3 or 7 days. Animals were randomly divided into groups: 6 GNP-treated rats groups and one control group (NG. Groups 1, 2 and 3 received infusions of 50 μl GNPs of size 10 nm (3 or 7 days, 20 nm (3 or 7 days and 50 nm (3 or 7 days, respectively. Results In comparison with the respective control rats, exposure to GNPs doses produced heart muscle disarray with a few scattered chronic inflammatory cells infiltrated by small lymphocytes, foci of hemorrhage with extravasation of red blood cells, some scattered cytoplasmic vacuolization and congested and dilated blood vessels. None of the above alterations were observed in the heart muscle of any member of the control group. Conclusions The alterations induced by intraperitoneal administration of GNPs were size-dependent, with smaller ones inducing greater affects, and were also related to the time exposure to

  6. Effect of single and repeated heat stress on chemical signals of heat shock response cascade in the rat's heart.

    Science.gov (United States)

    Ilievska, Gordana; Dinevska-Kjovkarovska, Suzana; Miova, Biljana

    2017-11-24

    Exposure to sublethal heat stress activates a complex cascade of signaling events, such as activators (NO), signal molecules (PKCε), and mediators (HSP70 and COX-2), leading to implementation of heat preconditioning, an adaptive mechanism which makes the organism more tolerant to additional stress. We investigated the time frame in which these chemical signals are triggered after heat stress (41 ± 0.5°С/45 min), single or repeated (24 or 72 h after the first one) in heart tissue of male Wistar rats. The animals were allowed to recover 24, 48 or 72 h at room temperature. Single heat stress caused a significant increase of the concentration of HSP70, NO, and PKC level and decrease of COX-2 level 24 h after the heat stress, which in the next course of recovery gradually normalized. The second heat stress, 24 h after the first one, caused a significant reduction of the HSP70 levels, concentration of NO and PKCɛ, and significant increase of COX-2 concentration. The second exposure, 72 h after the first heat stress, caused more expressive changes of HSP70 and NO in the 24 h-recovery groups. The level of PKCɛ was not significantly changed, but there was significantly increased COX-2 concentration during recovery. Serum activity of AST, ALT, and CK was reduced after single exposure and increased after repeated exposure to heat stress, in both time intervals. In conclusion, a longer period of recovery (72 h) between two consecutive sessions of heat stress is necessary to achieve more expressive changes in mediators (HSP70) and triggers (NO) of heat preconditioning.

  7. Lower limb muscle pre-motor time measures during a choice reaction task associate with knee abduction loads during dynamic single leg landings.

    Science.gov (United States)

    McLean, Scott G; Borotikar, Bhushan; Lucey, Sarah M

    2010-07-01

    Female neuromuscular control during dynamic landings is considered central to their increased ACL injury risk relative to males. There is limited insight, however, into the neuromuscular parameters governing this risk, which may hinder prevention success. This study targeted a new screenable and potentially trainable neuromuscular risk factor. Specifically, we examined whether lower limb muscle pre-motor times, being the time between stimulus presentation and initiation of the muscle EMG burst, elicited during a simple choice reaction task correlated with knee abduction loads during separate single leg landings. Twenty female NCAA athletes had muscle (n=8) pre-motor time and knee biomechanics data recorded bilaterally during a choice reaction task. Knee biomechanics were also quantified during anticipated and unanticipated single (dominant and non-dominant) leg landings. Mean peak knee abduction loads during landings were submitted to a two-way ANOVA to test for limb and decision effects. Individual regression coefficients were initially computed between-limb-based muscle pre-motor times and peak abduction moments elicited during both the choice reaction and landing tasks. Limb-based linear stepwise regression coefficients were also computed between muscle PMT's demonstrating significant (Pmuscle pre-motor times during a specific choice reaction task are associated with peak knee abduction loads during separate single leg landings. These muscles appear critical in stabilizing the knee against the extreme dynamic load states associated with such tasks. Targeted screening and training of supraspinal processes governing these muscle pre-motor times may ultimately enable external knee loads associated with landings to be more effectively countered by the overarching neuromuscular strategy. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  8. Spatial and frequency domain ring source models for the single muscle fiber action potential

    DEFF Research Database (Denmark)

    Henneberg, Kaj-åge; R., Plonsey

    1994-01-01

    In the paper, single-fibre models for the extracellular action potential are developed that will allow the potential to the evaluated at an arbitrary field point in the extracellular space. Fourier-domain models are restricted in that they evaluate potentials at equidistant points along a line...... parallel to the fibre axis. Consequently, they cannot easily evaluate the potential at the boundary nodes of a boundary-element electrode model. The Fourier-domain models employ axial-symmetric ring source models, and thereby provide higher accuracy that the line source model, where the source is lumped...... including anisotropy show that the spatial models require extreme care in the integration procedure owing to the singularity in the weighting functions. With adequate sampling, the spatial models can evaluate extracellular potentials with high accuracy....

  9. Thrombotic complications and thromboprophylaxis across all three stages of single ventricle heart palliation.

    Science.gov (United States)

    Manlhiot, Cedric; Brandão, Leonardo R; Kwok, Judith; Kegel, Stefan; Menjak, Ines B; Carew, Caitlin L; Chan, Anthony K; Schwartz, Steven M; Sivarajan, V Ben; Caldarone, Christopher A; Van Arsdell, Glen S; McCrindle, Brian W

    2012-09-01

    To describe the incidence of thrombotic complications across all 3 stages of single ventricle palliation and the association between thromboprophylaxis use and thrombotic risk. Two separate cross-sectional studies were performed that included 195 patients born between 2003-2008 and 162 patients who underwent Fontan after 2000. The incidence of thrombotic complications was 40% and 28% after initial palliation and superior cavopulmonary connection (SCPC), respectively; 5-year freedom from thrombotic complications after Fontan was 79%. Thromboprophylaxis was initiated for 70%, 46%, and 94% of patients after initial palliation, SCPC, and Fontan, respectively. Thromboprophylaxis with enoxaparin (vs no thromboprophylaxis) was associated with a reduction in risk of thrombotic complications after initial palliation (hazard ratio [HR] 0.5, P = .05) and SCPC (HR 0.2, P = .04). Thromboprophylaxis with warfarin was associated with a reduction in thrombotic complications after Fontan (HR 0.27, P = .05 vs acetylsalicylic acid; HR 0.18, P = .02 vs no thromboprophylaxis). Thrombotic complications were associated with increased mortality after initial palliation (HR 5.5, P SCPC (HR 12.5, P < .001). Three patients experienced major bleeding complications without permanent sequelae (2 enoxaparin, 1 warfarin). Given the negative impact of thrombotic complications on survival, the low risk of serious bleeding complications, and the association between thromboprophylaxis and lowered thrombotic complication risk across all 3 palliative stages, routine use of thromboprophylaxis from the initial palliation to the early post-Fontan period in this population may be indicated. Copyright © 2012 Mosby, Inc. All rights reserved.

  10. Mechanical properties of mammalian single smooth muscle cells. II. Evaluation of a modified technique for attachment of cells to the measurement apparatus

    NARCIS (Netherlands)

    J.J. Glerum (Jacobus); R. van Mastrigt (Ron)

    1990-01-01

    textabstractA method is described for attaching isolated single smooth muscle cells to an apparatus designed for measuring the longitudinal forces developed passively and actively by the cell upon straining, electrical or pharmacological stimulation. Primary attachment of the cell is based on its

  11. Effect of race on the timing of the Glenn and Fontan procedures for single-ventricle congenital heart disease.

    Science.gov (United States)

    Ingaramo, Oscar A; Khemani, Robinder G; Markovitz, Barry P; Epstein, David

    2012-03-01

    Disparities in health care have been documented between different racial groups in the United States. We hypothesize that there will be racial variance in the timing of the Glenn and Fontan procedures for children with single-ventricle physiology. We performed a retrospective review of a national pediatric intensive care unit database (Virtual PICU Performance System, LLC). Children with hypoplastic left heart syndrome, tricuspid atresia, and common ventricle, admitted from January 2006 to July 2008, were included. Data included race, weight, age, medical length of stay, Paediatric Index of Mortality 2 score, and survival. None. There were 423 patients from 29 hospitals. The study population was 7.6% black, 13.0% Hispanic, 59.8% white, 9.2% "other," and 11.6% had missing racial/ethnic information. Diagnoses included 255 patients with hypoplastic left heart syndrome, 91 with tricuspid atresia, and 77 with common ventricle. The median age for the Glenn procedure (n = 205) was 5.5 months (interquartile range, 4.6-7.0 months) and 39.7 months (interquartile range, 32.4-50.6 months) for the Fontan procedure (n = 218). There was no difference between the median age at the time of the Glenn or Fontan procedures between the different racial/ethnic groups (p = .65 and p = .16, respectively). The medical length of intensive care unit stay for patients receiving the Glenn and Fontan procedures was 3.7 days (interquartile range, 1.9-6.1 days) and 3.7 days (interquartile range, 1.9-6.8 days), respectively. There were no differences in medical length of intensive care unit stay for the Glenn procedure between the different racial/ethnic groups (p = .21). Hispanic patients had a longer medical length of intensive care unit stay (6.3 days; interquartile range, 3.1-9.9 days) than white patients (2.9 days; interquartile range, 1.8-5.3 days) for the Fontan procedure (p = .008). The timing of single-ventricle palliative procedures was not affected by race/ethnicity.

  12. Myofascial force transmission in dynamic muscle conditions: effects of dynamic shortening of a single head of multi-tendoned rat extensor digitorum longus muscle.

    Science.gov (United States)

    Maas, Huub; Huijing, Peter A

    2005-08-01

    This study investigated the effects of myofascial force transmission during dynamic shortening of head III of rat extensor digitorum longus muscle (EDL III). The anterior crural compartment was left intact. Force was measured simultaneously at the distal EDL III tendon, the proximal EDL tendon and the distal tendons of tibialis anterior and extensor hallucis longus muscles (TA + EHL). Two types of distal shortening of EDL III were studied: (1) sinusoidal shortening (2 mm) and (2) isokinetic shortening (8 mm). Sinusoidal shortening of EDL III caused a decrease in force exerted at the distal tendon of EDL III: from 0.58 (0.08) N to 0.26 (0.04) N. In contrast, hardly any changes in proximal EDL force and distal TA+EHL force were found. Maximal concentric force exerted at the distal tendon of EDL III was higher than maximal isometric force expected on the basis of the physiological cross-sectional area of EDL III muscle fibers (Maas et al. 2003). Therefore, a substantial fraction of this force must originate from sources other than muscle fibers of EDL III. Isokinetic shortening of EDL III caused high changes in EDL III force from 0.97 (0.15) N to zero. In contrast, changes in proximal EDL force were much smaller: from 2.44 (0.25) N to 1.99 (0.19) N. No effects on TA + EHL force could be shown. These results are explained in terms of force transmission between the muscle belly of EDL III and adjacent tissues. Thus, also in dynamic muscle conditions, muscle fiber force is transmitted via myofascial pathways.

  13. An examination of resveratrol's mechanisms of action in human tissue: impact of a single dose in vivo and dose responses in skeletal muscle ex vivo.

    Directory of Open Access Journals (Sweden)

    Cameron B Williams

    Full Text Available The current study tested the hypothesis that a single, moderate dose of RSV would activate the AMPK/SIRT1 axis in human skeletal muscle and adipose tissue. Additionally, the effects of RSV on mitochondrial respiration in PmFBs were examined. Eight sedentary men (23.8±2.4 yrs; BMI: 32.7±7.1 reported to the lab on two occasions where they were provided a meal supplemented with 300 mg of RSV or a placebo. Blood samples, and a muscle biopsy were obtained in the fasted state and again, with the addition of an adipose tissue biopsy, two hours post-prandial. The effect of RSV on mitochondrial respiration was examined in PmFBs taken from muscle biopsies from an additional eight men (23.4±5.4 yrs; BMI: 24.4±2.8. No effect of RSV was observed on nuclear SIRT1 activity, acetylation of p53, or phosphorylation of AMPK, ACC or PKA in either skeletal muscle or adipose tissue. A decrease in post absorptive insulin levels was accompanied by elevated skeletal muscle phosphorylation of p38 MAPK, but no change in either skeletal muscle or adipose tissue insulin signalling. Mitochondrial respiration in PmFBs was rapidly inhibited by RSV at 100-300 uM depending on the substrate examined. These results question the efficacy of a single dose of RSV at altering skeletal muscle and adipose tissue AMPK/SIRT1 activity in humans and suggest that RSV mechanisms of action in humans may be associated with altered cellular energetics resulting from impaired mitochondrial ATP production.

  14. L-arginine supplementation protects exercise performance and structural integrity of muscle fibers after a single bout of eccentric exercise in rats.

    Directory of Open Access Journals (Sweden)

    Yulia N Lomonosova

    Full Text Available Eccentric exercise is known to disrupt sarcolemmal integrity and induce damage of skeletal muscle fibers. We hypothesized that L-arginine (L-Arg; nitric oxide synthase (NOS substrate supplementation prior to a single bout of eccentric exercise would diminish exercise-induced damage. In addition, we used N-nitro-L-arginine methyl ester hydrochloride (L-NAME; NOS inhibitor to clarify the role of native NOS activity in the development of exercise-induced muscle damage. Rats were divided into four groups: non-treated control (C, downhill running with (RA or without (R L-Arg supplementation and downhill running with L-NAME supplementation (RN. Twenty four hours following eccentric exercise seven rats in each group were sacrificed and soleus muscles were dissected and frozen for further analysis. The remaining seven rats in each group were subjected to the exercise performance test. Our experiments showed that L-Arg supplementation prior to a single bout of eccentric exercise improved subsequent exercise performance capacity tests in RA rats when compared with R, RN and C rats by 37%, 27% and 13%, respectively. This outcome is mediated by L-Arg protection against post-exercise damage of sarcolemma (2.26- and 0.87-fold less than R and RN groups, respectively, reduced numbers of damaged muscle fibers indicated by the reduced loss of desmin content in the muscle (15% and 25% less than R and RN groups, respectively, and diminished µ-calpain mRNA up-regulation (42% and 30% less than R and RN groups, respectively. In conclusion, our study indicates that L-Arg supplementation prior to a single bout of eccentric exercise alleviates muscle fiber damage and preserves exercise performance capacity.

  15. L-arginine supplementation protects exercise performance and structural integrity of muscle fibers after a single bout of eccentric exercise in rats.

    Science.gov (United States)

    Lomonosova, Yulia N; Shenkman, Boris S; Kalamkarov, Grigorii R; Kostrominova, Tatiana Y; Nemirovskaya, Tatyana L

    2014-01-01

    Eccentric exercise is known to disrupt sarcolemmal integrity and induce damage of skeletal muscle fibers. We hypothesized that L-arginine (L-Arg; nitric oxide synthase (NOS) substrate) supplementation prior to a single bout of eccentric exercise would diminish exercise-induced damage. In addition, we used N-nitro-L-arginine methyl ester hydrochloride (L-NAME; NOS inhibitor) to clarify the role of native NOS activity in the development of exercise-induced muscle damage. Rats were divided into four groups: non-treated control (C), downhill running with (RA) or without (R) L-Arg supplementation and downhill running with L-NAME supplementation (RN). Twenty four hours following eccentric exercise seven rats in each group were sacrificed and soleus muscles were dissected and frozen for further analysis. The remaining seven rats in each group were subjected to the exercise performance test. Our experiments showed that L-Arg supplementation prior to a single bout of eccentric exercise improved subsequent exercise performance capacity tests in RA rats when compared with R, RN and C rats by 37%, 27% and 13%, respectively. This outcome is mediated by L-Arg protection against post-exercise damage of sarcolemma (2.26- and 0.87-fold less than R and RN groups, respectively), reduced numbers of damaged muscle fibers indicated by the reduced loss of desmin content in the muscle (15% and 25% less than R and RN groups, respectively), and diminished µ-calpain mRNA up-regulation (42% and 30% less than R and RN groups, respectively). In conclusion, our study indicates that L-Arg supplementation prior to a single bout of eccentric exercise alleviates muscle fiber damage and preserves exercise performance capacity.

  16. Association of body size and muscle strength with incidence of coronary heart disease and cerebrovascular diseases: a population-based cohort study of one million Swedish men.

    Science.gov (United States)

    Silventoinen, Karri; Magnusson, Patrik K E; Tynelius, Per; Batty, G David; Rasmussen, Finn

    2009-02-01

    Muscle strength and body size may be associated with coronary heart disease (CHD) and stroke risk. However, perhaps because of a low number of cases, existing evidence is inconsistent. Height, weight, systolic (SBP) and diastolic blood pressure (DBP), elbow flexion, hand grip and knee extension strength were measured in young adulthood in 1 145 467 Swedish men born between 1951 and 1976. Information on own and parental social position was derived from censuses. During the register-based follow-up until the end of 2006, 12 323 CHD and 8865 stroke cases emerged, including 1431 intracerebral haemorrhage, 1316 subarachoid haemorrhage and 2944 intracerebral infarction cases. Hazard ratios (HR) per 1 SD in the exposures of interest were computed using Cox proportional hazard model. Body mass index (BMI, kg/m(2)) showed increased risk with CHD and intracerebral infarction, whereas for intracerebral and subarachoid haemorrhage both under- and overweight was associated with increased risk. Height was inversely associated with CHD and all types of stroke. After adjustment for height, BMI, SBP, DBP and social position, all strength indicators were inversely associated with disease risk. For CHD and intracerebral infarction, grip strength showed the strongest association (HR = 0.89 and 0.91, respectively) whereas for intracerebral and subarachoid haemorrhage, knee extension strength was the best predictor (HR = 0.88 and 0.92, respectively). Body size and muscle strength in young adulthood are important predictors of risk of CHD and stroke in later life. In addition to adiposity, underweight needs attention since it may predispose to cerebrovascular complications.

  17. Smooth Muscle Cells Derived From Second Heart Field and Cardiac Neural Crest Reside in Spatially Distinct Domains in the Media of the Ascending Aorta-Brief Report.

    Science.gov (United States)

    Sawada, Hisashi; Rateri, Debra L; Moorleghen, Jessica J; Majesky, Mark W; Daugherty, Alan

    2017-09-01

    Smooth muscle cells (SMCs) of the proximal thoracic aorta are embryonically derived from the second heart field (SHF) and cardiac neural crest (CNC). However, distributions of these embryonic origins are not fully defined. The regional distribution of SMCs of different origins is speculated to cause region-specific aortopathies. Therefore, the aim of this study was to determine the distribution of SMCs of SHF and CNC origins in the proximal thoracic aorta. Mice with repressed LacZ in the ROSA26 locus were bred to those expressing Cre controlled by either the Wnt1 or Mef2c (myocyte-specific enhancer factor 2c) promoter to trace CNC- and SHF-derived SMCs, respectively. Thoracic aortas were harvested, and activity of β-galactosidase was determined. Aortas from Wnt1- Cre mice had β-galactosidase-positive areas throughout the region from the proximal ascending aorta to just distal of the subclavian arterial branch. Unexpectedly, β-galactosidase-positive areas in Mef2c- Cre mice extended from the aortic root throughout the ascending aorta. This distribution occurred independent of sex and aging. Cross and sagittal aortic sections demonstrated that CNC-derived cells populated the inner medial aspect of the anterior region of the ascending aorta and transmurally in the media of the posterior region. Interestingly, outer medial cells throughout anterior and posterior ascending aortas were derived from the SHF. β-Galactosidase-positive medial cells of both origins colocalized with an SMC marker, α-actin. Both CNC- and SHF-derived SMCs populate the media throughout the ascending aorta. The outer medial cells of the ascending aorta form a sleeve populated by SHF-derived SMCs. © 2017 American Heart Association, Inc.

  18. Myofascial force transmission in dynamic muscle conditions: effects of dynamic shortening of a single head of multi-tendoned rat extensor digitorum longus muscle

    NARCIS (Netherlands)

    Maas, H.; Huijing, P.A.J.B.M.

    2005-01-01

    This study investigated the effects of myofascial force transmission during dynamic shortening of head III of rat extensor digitorum longus muscle (EDL III). The anterior crural compartment was left intact. Force was measured simultaneously at the distal EDL III tendon, the proximal EDL tendon and

  19. Formation of highly organized intracellular structure and energy metabolism in cardiac muscle cells during postnatal development of rat heart.

    Science.gov (United States)

    Anmann, Tiia; Varikmaa, Minna; Timohhina, Natalja; Tepp, Kersti; Shevchuk, Igor; Chekulayev, Vladimir; Saks, Valdur; Kaambre, Tuuli

    2014-08-01

    Adult cardiomyocytes have highly organized intracellular structure and energy metabolism whose formation during postnatal development is still largely unclear. Our previous results together with the data from the literature suggest that cytoskeletal proteins, particularly βII-tubulin, are involved in the formation of complexes between mitochondria and energy consumption sites. The aim of this study was to examine the arrangement of intracellular architecture parallel to the alterations in regulation of mitochondrial respiration in rat cardiomyocytes during postnatal development, from 1 day to 6 months. Respirometric measurements were performed to study the developmental alterations of mitochondrial function. Changes in the mitochondrial arrangement and cytoarchitecture of βII- and αIV-tubulin were examined by confocal microscopy. Our results show that functional maturation of oxidative phosphorylation in mitochondria is completed much earlier than efficient feedback regulation is established between mitochondria and ATPases via creatine kinase system. These changes are accompanied by significant remodeling of regular intermyofibrillar mitochondrial arrays aligned along the bundles of βII-tubulin. Additionally, we demonstrate that formation of regular arrangement of mitochondria is not sufficient per se to provide adult-like efficiency in metabolic feed-back regulation, but organized tubulin networks and reduction in mitochondrial outer membrane permeability for ADP are necessary as well. In conclusion, cardiomyocytes in rat heart become mature on the level of intracellular architecture and energy metabolism at the age of 3 months. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. The influence of muscle action on heart rate, RPE, and affective responses after upper-body resistance exercise.

    Science.gov (United States)

    Miller, Paul C; Hall, Eric E; Chmelo, Elizabeth A; Morrison, Jeffrey M; DeWitt, Rachel E; Kostura, Christine M

    2009-03-01

    Ratings of perceived exertion (RPE) are routinely used to monitor, assess, and prescribe aerobic exercise. Heart rate (HR) is another measure used to evaluate exercise intensity. Additionally, affective responses to aerobic exercise have been studied and seem to be influenced by the intensity of the exercise. The perceptual, HR, and affective responses to resistance exercise have not been effectively established. The purpose of this study was to examine whether differences in affect, RPE, and HR exist among college-aged women (n = 31) performing three different modes of resistance training: concentric (CE), eccentric (EE), and traditional concentric/eccentric (TE) performed at varying resistances. The women were asked to complete four sessions of resistance training on variable resistance machines: chest press, seated row, overhead press, and biceps curl. The first session was used to establish the 10-repetition maximum (RM) load for each station. Subsequent sessions involved the execution of training in one of the three test conditions: CE, EE, or TE. The participants performed three sets of each lift at 80% 10-RM, 100% 10-RM, and 120% 10-RM. The data revealed lower RPE during EE than the other test conditions. Similarly, EE elicited more mild HR response than either CE or TE. This finding is potentially important for the establishment of training programs, especially for those individuals recovering from an illness, who had been previously sedentary, and who are involved in rehabilitation of an injury.

  1. Up-regulation of alpha-smooth muscle actin in cardiomyocytes from non-hypertrophic and non-failing transgenic mouse hearts expressing N-terminal truncated cardiac troponin I

    Directory of Open Access Journals (Sweden)

    Stephanie Kern

    2014-01-01

    Full Text Available We previously reported that a restrictive N-terminal truncation of cardiac troponin I (cTnI-ND is up-regulated in the heart in adaptation to hemodynamic stresses. Over-expression of cTnI-ND in the hearts of transgenic mice revealed functional benefits such as increased relaxation and myocardial compliance. In the present study, we investigated the subsequent effect on myocardial remodeling. The alpha-smooth muscle actin (α-SMA isoform is normally expressed in differentiating cardiomyocytes and is a marker for myocardial hypertrophy in adult hearts. Our results show that in cTnI-ND transgenic mice of between 2 and 3 months of age (young adults, a significant level of α-SMA is expressed in the heart as compared with wild-type animals. Although blood vessel density was increased in the cTnI-ND heart, the mass of smooth muscle tissue did not correlate with the increased level of α-SMA. Instead, immunocytochemical staining and Western blotting of protein extracts from isolated cardiomyocytes identified cardiomyocytes as the source of increased α-SMA in cTnI-ND hearts. We further found that while a portion of the up-regulated α-SMA protein was incorporated into the sarcomeric thin filaments, the majority of SMA protein was found outside of myofibrils. This distribution pattern suggests dual functions for the up-regulated α-SMA as both a contractile component to affect contractility and as possible effector of early remodeling in non-hypertrophic, non-failing cTnI-ND hearts.

  2. Mitochondrial affinity for ADP is twofold lower in creatine kinase knock-out muscles - Possible role in rescuing cellular energy homeostasis

    NARCIS (Netherlands)

    ter Veld, F; Jeneson, JAL; Nicolay, K

    Adaptations of the kinetic properties of mitochondria in striated muscle lacking cytosolic (M) and/or mitochondrial (Mi) creatine kinase (CK) isoforms in comparison to wild-type (WT) were investigated in vitro. Intact mitochondria were isolated from heart and gastrocnemius muscle of WT and single-

  3. Beneficial Effects of Physical Exercise on Functional Capacity and Skeletal Muscle Oxidative Stress in Rats with Aortic Stenosis-Induced Heart Failure

    Directory of Open Access Journals (Sweden)

    Mariana Janini Gomes

    2016-01-01

    Full Text Available Objective. We evaluated the influence of exercise on functional capacity, cardiac remodeling, and skeletal muscle oxidative stress, MAPK, and NF-κB pathway in rats with aortic stenosis- (AS- induced heart failure (HF. Methods and Results. Eighteen weeks after AS induction, rats were assigned into sedentary control (C-Sed, exercised control (C-Ex, sedentary AS (AS-Sed, and exercised AS (AS-Ex groups. Exercise was performed on treadmill for eight weeks. Statistical analyses were performed with Goodman and ANOVA or Mann-Whitney. HF features frequency and mortality did not differ between AS groups. Exercise improved functional capacity, assessed by maximal exercise test on treadmill, without changing echocardiographic parameters. Soleus cross-sectional areas did not differ between groups. Lipid hydroperoxide concentration was higher in AS-Sed than C-Sed and AS-Ex. Activity of antioxidant enzymes superoxide dismutase and glutathione peroxidase was changed in AS-Sed and restored in AS-Ex. NADPH oxidase activity and gene expression of its subunits did not differ between AS groups. Total ROS generation was lower in AS-Ex than C-Ex. Exercise modulated MAPK in AS-Ex and did not change NF-κB pathway proteins. Conclusion. Exercise improves functional capacity in rats with AS-induced HF regardless of echocardiographic parameter changes. In soleus, exercise reduces oxidative stress, preserves antioxidant enzyme activity, and modulates MAPK expression.

  4. Stress and your heart

    Science.gov (United States)

    Coronary heart disease - stress; Coronary artery disease - stress ... Your body responds to stress on many levels. First, it releases stress hormones that make you breathe faster. Your blood pressure goes up. Your muscles ...

  5. Controlled reoxygenation during cardiopulmonary bypass decreases markers of organ damage, inflammation, and oxidative stress in single-ventricle patients undergoing pediatric heart surgery.

    Science.gov (United States)

    Caputo, Massimo; Mokhtari, Amir; Miceli, Antonio; Ghorbel, Mohamed T; Angelini, Gianni D; Parry, Andrew J; Suleiman, Saadeh M

    2014-09-01

    Single-ventricle patients undergoing pediatric heart surgery are a high-risk group owing to reoxygenation injury during cardiopulmonary bypass (CPB). The present study investigated the effects of controlled reoxygenation CPB on biomarkers of organ damage, inflammation, stress, and long-term functional outcomes in cyanotic patients with either a single or double ventricle during open heart surgery. Cyanotic patients with either a single (n = 32) or double (n = 47) ventricle undergoing surgical correction were randomized to receive CPB using either standard oxygen levels or controlled reoxygenation. The markers of cardiac injury, inflammation, stress, and cerebral and hepatic injury were measured preoperatively, at 10 and 30 minutes after starting CPB, and at 10 minutes and 4 and 24 hours after CPB. The data were analyzed using a mixed regression model. No difference was found in the pre- or intraoperative characteristics between the standard and controlled reoxygenation CPB groups for single- or double-ventricle patients. In the single-ventricle patients, controlled reoxygenation CPB significantly (P markers of organ damage, inflammation, stress, and oxidative stress. In contrast, the markers of inflammation and cardiac injury were not altered by controlled reoxygenation CPB in the double-ventricle patients. Controlled reoxygenation CPB decreased the markers of organ damage, stress, inflammation, and oxidative stress in single-ventricle patients undergoing cardiac surgery. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  6. Epicardial mapping of ventricular fibrillation over the posterior descending artery and left posterior papillary muscle of the swine heart.

    Science.gov (United States)

    Nielsen, Thomas D; Huang, Jian; Rogers, Jack M; Killingsworth, Cheryl R; Ideker, Raymond E

    2009-01-01

    Recent studies suggest that during ventricular fibrillation (VF) epicardial vessels may be a site of conduction block and the posterior papillary muscle (PPM) in the left ventricle (LV) may be the location of a "mother rotor." The goal of this study was to obtain evidence to support or refute these possibilities. Epicardial activation over the posterior LV and right ventricle (RV) was mapped during the first 20 s of electrically induced VF in six open-chest pigs with a 504 electrode plaque covering a 20 cm(2) area centered over the posterior descending artery (PDA). The locations of epicardial breakthrough as well as reentry clustered in time and space during VF. Spatially, reentry occurred significantly more frequently over the LV than the RV in all 48 episodes, and breakthrough clustered near the PPM (p < 0.001). Significant temporal clustering occurred in 79% of breakthrough episodes and 100% of reentry episodes. These temporal clusters occurred at different times so that there was significantly less breakthrough when reentry was present (p < 0.0001). Conduction block occurred significantly more frequently near the PDA than elsewhere. The PDA is a site of epicardial block which may contribute to VF maintenance. Epicardial breakthrough clusters near the PPM. Reentry also clusters in space but at a separate site. The fact that breakthrough and reentry cluster at different locations and at different times supports the possibility of a drifting filament at the PPM so that at times reentry is present on the surface but at other times the reentrant wavefront breaks through to the epicardium.

  7. Skeletal muscle mechanics: questions, problems and possible solutions.

    Science.gov (United States)

    Herzog, Walter

    2017-09-16

    Skeletal muscle mechanics have been studied ever since people have shown an interest in human movement. However, our understanding of muscle contraction and muscle mechanical properties has changed fundamentally with the discovery of the sliding filament theory in 1954 and associated cross-bridge theory in 1957. Nevertheless, experimental evidence suggests that our knowledge of the mechanisms of contraction is far from complete, and muscle properties and muscle function in human movement remain largely unknown.In this manuscript, I am trying to identify some of the crucial challenges we are faced with in muscle mechanics, offer possible solutions to questions, and identify problems that might be worthwhile exploring in the future. Since it is impossible to tackle all (worthwhile) problems in a single manuscript, I identified three problems that are controversial, important, and close to my heart. They may be identified as follows: (i) mechanisms of muscle contraction, (ii) in vivo whole muscle mechanics and properties, and (iii) force-sharing among synergistic muscles. These topics are fundamental to our understanding of human movement and movement control, and they contain a series of unknowns and challenges to be explored in the future.It is my hope that this paper may serve as an inspiration for some, may challenge current beliefs in selected areas, tackle important problems in the area of muscle mechanics, physiology and movement control, and may guide and focus some of the thinking of future muscle mechanics research.

  8. Heart failure in patients with sick sinus syndrome treated with single lead atrial or dual-chamber pacing

    DEFF Research Database (Denmark)

    Riahi, Sam; Nielsen, Jens Cosedis; Hjortshøj, Søren

    2012-01-01

    AIMS: Previous studies indicate that ventricular pacing may precipitate heart failure (HF). We investigated occurrence of HF during long-term follow-up among patients with sick sinus syndrome (SSS) randomized to AAIR or DDDR pacing. Furthermore, we investigated effects of percentage of ventricular...... during follow-up. Patients were classified with new HF, if in New York Heart Association (NYHA) functional class IV or if presence of ≥2 of: oedema; dyspnoea; NYHA functional class III. Mean follow-up was 5.4 ± 2.4 years. Heart failure hospitalizations did not differ between groups. In the AAIR group...

  9. The influence of single and fractionated dose external beam irradiation on injury-induced arterial smooth muscle cell proliferation

    International Nuclear Information System (INIS)

    Schaefer, U.; Micke, O.; Dorszewski, A.; Breithardt, G.; Willich, N.

    1997-01-01

    Purpose/Objective: Restenosis after catheter-based revascularization has been demonstrated to be primarily caused by smooth muscle cell proliferation. This study examined the effects of external beam irradiation on neointimal proliferation after external injury to the central artery of the rabbit ear. Materials and Methods: 40 male New Zealand White rabbits were used in this study. Crush lesions were performed on each ear under general anesthesia and bilateral auricular nerve blockade. A single dose of 12 Gy (n=10), 16 Gy (n=10), or 20 Gy (n=10) and a fractionated dose of 4 x 5 Gy (n=10) gamma radiation was delivered to the left or right central artery of the ear 24 hours after injury; the contralateral central artery served as control. All rabbits were sacrificed after twenty-one days and the central arteries of the ear were fixed for morphometric measurements. Results: Mean (± SD) neointimal area was 0.062 ± 0.005 mm 2 (12 Gy), 0.022 ± 0,005 mm 2 (16 Gy), 0,028 ± 0,006 mm 2 and 0.038 mm 2 ± 0,02 mm 2 (4 x 5 Gy) in irradiated arteries compared with 0,081 ± 0,009 mm 2 in the control group. Mean (±SD) luminal area was 0.049 ± 0.004 mm 2 (12 Gy), 0.059 ± 0.002 mm 2 (16 Gy), 0.072 ± 0,006 mm 2 (20 Gy) and 0.048 mm 2 ± 0,018 mm 2 (4 x 5 Gy) in irradiated arteries compared with 0,043 ± 0,008 mm 2 in the control group. The difference in neointimal and luminal area between control and irradiated arteries was significant (p<0.05) only for the 16 and 20 Gy group compared to control. Conclusion: We conclude that in this model, external beam X-ray irradiation was successful in reducing neointimal proliferation after injury of the central artery of the rabbit ear. The optimal dose seems to be a single dose of 16 Gy - 20 Gy. Only a less prominent effect was noted for a fractionated dose of 4 x 5 Gy. Whether this approach can be used successfully to inhibit restenosis in the clinical setting requires further investigation

  10. Delayed diagnosis of single compartment muscle contusion after radical hysterectomy in the lithotomy position: A case report

    Directory of Open Access Journals (Sweden)

    Kenro Chikazawa

    2016-01-01

    Conclusion: Magnetic resonance imaging is useful for diagnosis. For patients who complain of edema and tenderness in the lower leg after surgery in the lithotomy position, muscle contusions should be considered.

  11. The effects of a single bout of downhill running and ensuing delayed onset of muscle soreness on running economy performed 48 h later.

    Science.gov (United States)

    Braun, William A; Dutto, Darren J

    2003-09-01

    Delayed onset of muscle soreness (DOMS) is a common response to exercise involving significant eccentric loading. Symptoms of DOMS vary widely and may include reduced force generating capacity, significant alterations in biochemical indices of muscle and connective tissue health, alteration of neuromuscular function, and changes in mechanical performance. The purpose of the investigation was to examine the effects of downhill running and ensuing DOMS on running economy and stride mechanics. Nine, well-trained distance runners and triathletes participated in the study. Running economy was measured at three relative intensities [65, 75, and 85% of maximal aerobic capacity ( VO(2peak))] before (RE1) and 48 h after (RE2) a 30-min downhill run (-10%) at 70% VO(2peak). Dependent variables included leg muscle soreness, rate of oxygen consumption ( VO(2)), minute ventilation, respiratory exchange ratio, lactate, heart rate, and stride length. These measurements were entered into a two-factor multivariate analysis of variance (MANOVA). The analysis revealed a significant time effect for all variables and a significant interaction (time x intensity) for lactate. The energy cost of locomotion was elevated at RE2 by an average of 3.2%. This was coupled with a significant reduction in stride length. The change in VO(2) was inversely correlated with the change in stride length ( r= -0.535). Lactate was significantly elevated at RE2 for each run intensity, with a mean increase of 0.61 mmol l(-1). Based on these findings, it is suggested that muscle damage led to changes in stride mechanics and a greater reliance on anaerobic methods of energy production, contributing to the change in running economy during DOMS.

  12. Improvements in kinematics, muscle activity and pain during functional tasks in females with patellofemoral pain following a single patterned electrical stimulation treatment.

    Science.gov (United States)

    Glaviano, Neal R; Huntsman, Stephanie; Dembeck, Ashley; Hart, Joseph M; Saliba, Susan

    2016-02-01

    Individuals with patellofemoral pain present with altered hip muscle activation, faulty movement patterns, and pain during functional tasks. Examining new treatment options to address these impairments may better treat those with patellofemoral pain. The purpose of this study was to determine if patterned electrical stimulation to the lower extremity affects muscle activity, movement patterns, and pain following a single treatment. Fifteen females with patellofemoral pain were randomized to receive a single 15-minute treatment of either a patterned electrical neuromuscular stimulation or a sham. Peak kinematics of the knee, hip, and trunk, electromyography and pain were examined pre and post-intervention during a single leg squat and lateral step-down task. Group means and pre/post reduced kinematic values were also plotted during the entire task with 90% confidence intervals to identify differences in movement strategies. No baseline differences were found in peak kinematics between groups. No pre to post-intervention differences in peak knee, hip and trunk kinematics were found, however differences were seen when the quality of movement across the entire tasks was assessed. The electrical stimulation group had improved knee flexion and hip abduction during the lateral step-down. A significant improvement in gluteus medius activation following patterned electrical neuromuscular stimulation occurred during the step-down (P=0.039). Significant pain improvements were also seen in both the single leg squat (P=0.025) and lateral step-down (P=0.006). A single treatment of patterned electrical neuromuscular stimulation improved muscle activation, lower extremity kinematics during functional tasks, and pain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. THE EFFECTS OF SINGLE LEG HOP PROGRESSION AND DOUBLE LEGS HOP PROGRESSION EXERCISE TO INCREASE SPEED AND EXPLOSIVE POWER OF LEG MUSCLE

    Directory of Open Access Journals (Sweden)

    Nining W. Kusnanik

    2015-05-01

    Full Text Available The main purpose of this study was to determine the effect of single leg hop progression and double legs hop progression exercise to increase speed and explosive power of leg muscles. Plyometric is one of the training methods that can increase explosive power. There are many models of plyometric training including single leg hop progression and double leg hop progression. This research was experimental using match subject design techniques. The subjects of this study were 39 students who joined basketball school club. There were 3 groups in this study: Group 1 were 13 students who given sin¬gle leg hop progression exercise, Group 2 were 13 students who given double legs hop progression exercise, Group 3 were 13 students who given conventional exercise. The data was collected during pre test and post test by testing 30m speed running and vertical jump. The data was analyzed using Analysis of Varians (Anova. It was found that there were significantly increased on speed and explosive power of leg muscles of Group 1 and Group 2. It can be stated that single leg hop progression exercise was more effective than double leg hop progression exercise. The recent findings supported the hypothesis that single leg hop progression and double legs hop progression exercise can increase speed and explosive power of leg muscles. These finding were supported by some previous studies (Singh, et al, 2011; Shallaby, H.K., 2010. The single leg hop progression is more effective than double legs hop progression. This finding was consistent with some previous evidences (McCurdy, et al, 2005; Makaruk et al, 2011.

  14. Relationships between knee valgus, hip-muscle strength, and hip-muscle recruitment during a single-limb step-down.

    Science.gov (United States)

    Hollman, John H; Ginos, Barbara E; Kozuchowski, Jakub; Vaughn, Amanda S; Krause, David A; Youdas, James W

    2009-02-01

    Reduced strength and activation of hip muscles might correlate with increased weight-bearing knee valgus. To describe relationships among frontal-plane hip and knee angles, hip-muscle strength, and electromyographic (EMG) recruitment in women during a step-down. Exploratory study. Laboratory. 20 healthy women 20 to 30 years of age. Frontal-plane hip and knee angles were measured. Gluteus maximus and medius recruitment were examined with surface EMG. Hip-abduction and -external-rotation strength were quantified with handheld dynamometry. The authors analyzed correlation coefficients between knee and hip angles, gluteus maximus and medius EMG, and hip-abduction and -external-rotation strength. Hip-adduction angles (r = .755, P = .001), gluteus maximus EMG (r = -.451, P = .026), and hip-abduction strength (r = .455, P = .022) correlated with frontal-plane projections of knee valgus. Gluteus maximus recruitment might have greater association with reduced knee valgus in women than does external-rotation strength during step-down tasks. Gluteus medius strength might be associated with increased knee valgus.

  15. Quality Control of Motor Unit Number Index (MUNIX Measurements in 6 Muscles in a Single-Subject "Round-Robin" Setup.

    Directory of Open Access Journals (Sweden)

    Christoph Neuwirth

    Full Text Available Motor Unit Number Index (MUNIX is a neurophysiological measure that provides an index of the number of lower motor neurons in a muscle. Its performance across centres in healthy subjects and patients with Amyotrophic Lateral Sclerosis (ALS has been established, but inter-rater variability between multiple raters in one single subject has not been investigated.To assess reliability in a set of 6 muscles in a single subject among 12 examiners (6 experienced with MUNIX, 6 less experienced and to determine variables associated with variability of measurements.Twelve raters applied MUNIX in six different muscles (abductor pollicis brevis (APB, abductor digiti minimi (ADM, biceps brachii (BB, tibialis anterior (TA, extensor dig. brevis (EDB, abductor hallucis (AH twice in one single volunteer on consecutive days. All raters visited at least one training course prior to measurements. Intra- and inter-rater variability as determined by the coefficient of variation (COV between different raters and their levels of experience with MUNIX were compared.Mean intra-rater COV of MUNIX was 14.0% (±6.4 ranging from 5.8 (APB to 30.3% (EDB. Mean inter-rater COV was 18.1 (±5.4 ranging from 8.0 (BB to 31.7 (AH. No significant differences of variability between experienced and less experienced raters were detected.We provide evidence that quality control for neurophysiological methods can be performed with similar standards as in laboratory medicine. Intra- and inter-rater variability of MUNIX is muscle-dependent and mainly below 20%. Experienced neurophysiologists can easily adopt MUNIX and adequate teaching ensures reliable utilization of this method.

  16. Piscine Orthoreovirus from Western North America Is Transmissible to Atlantic Salmon and Sockeye Salmon but Fails to Cause Heart and Skeletal Muscle Inflammation.

    Directory of Open Access Journals (Sweden)

    Kyle A Garver

    Full Text Available Heart and skeletal muscle inflammation (HSMI is a significant and often fatal disease of cultured Atlantic salmon in Norway. The consistent presence of Piscine orthoreovirus (PRV in HSMI diseased fish along with the correlation of viral load and antigen with development of lesions has supported the supposition that PRV is the etiologic agent of this condition; yet the absence of an in vitro culture system to demonstrate disease causation and the widespread prevalence of this virus in the absence of disease continues to obfuscate the etiological role of PRV with regard to HSMI. In this study, we explore the infectivity and disease causing potential of PRV from western North America-a region now considered endemic for PRV but without manifestation of HSMI-in challenge experiments modeled upon previous reports associating PRV with HSMI. We identified that western North American PRV is highly infective by intraperitoneal injection in Atlantic salmon as well as through cohabitation of both Atlantic and Sockeye salmon. High prevalence of viral RNA in peripheral blood of infected fish persisted for as long as 59 weeks post-challenge. Nevertheless, no microscopic lesions, disease, or mortality could be attributed to the presence of PRV, and only a minor transcriptional induction of the antiviral Mx gene occurred in blood and kidney samples during log-linear replication of viral RNA. Comparative analysis of the S1 segment of PRV identified high similarity between this North American sequence and previous sequences associated with HSMI, suggesting that factors such as viral co-infection, alternate PRV strains, host condition, or specific environmental circumstances may be required to cause this disease.

  17. How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution.

    Science.gov (United States)

    Schoenfeld, Brad Jon; Aragon, Alan Albert

    2018-01-01

    Controversy exists about the maximum amount of protein that can be utilized for lean tissue-building purposes in a single meal for those involved in regimented resistance training. It has been proposed that muscle protein synthesis is maximized in young adults with an intake of ~ 20-25 g of a high-quality protein; anything above this amount is believed to be oxidized for energy or transaminated to form urea and other organic acids. However, these findings are specific to the provision of fast-digesting proteins without the addition of other macronutrients. Consumption of slower-acting protein sources, particularly when consumed in combination with other macronutrients, would delay absorption and thus conceivably enhance the utilization of the constituent amino acids. The purpose of this paper was twofold: 1) to objectively review the literature in an effort to determine an upper anabolic threshold for per-meal protein intake; 2) draw relevant conclusions based on the current data so as to elucidate guidelines for per-meal daily protein distribution to optimize lean tissue accretion. Both acute and long-term studies on the topic were evaluated and their findings placed into context with respect to per-meal utilization of protein and the associated implications to distribution of protein feedings across the course of a day. The preponderance of data indicate that while consumption of higher protein doses (> 20 g) results in greater AA oxidation, this is not the fate for all the additional ingested AAs as some are utilized for tissue-building purposes. Based on the current evidence, we conclude that to maximize anabolism one should consume protein at a target intake of 0.4 g/kg/meal across a minimum of four meals in order to reach a minimum of 1.6 g/kg/day. Using the upper daily intake of 2.2 g/kg/day reported in the literature spread out over the same four meals would necessitate a maximum of 0.55 g/kg/meal.

  18. Effects of fatigue on lower limb, pelvis and trunk kinematics and lower limb muscle activity during single-leg landing after anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Lessi, Giovanna Camparis; Serrão, Fábio Viadanna

    2017-08-01

    Because there are no studies that have evaluated the effects of fatigue on the kinematics of the trunk and pelvis or on muscle activation in subjects with ACL reconstruction, the aim of this study was to evaluate the effects of fatigue on the lower limb, pelvis and trunk kinematics and lower limb muscle activation in subjects with ACL reconstruction during a single-leg landing compared to a healthy control group. The participants included 20 subjects with ACL reconstruction (ACL reconstruction group-ACLRG) and 20 healthy subjects (control group-CG) who were aged between 18 and 35 years. Kinematic and electromyographic analyses were performed during a single-leg landing before and after fatigue. The fatigue protocol included a series of 10 squats, two vertical jumps, and 20 steps. The effects of fatigue were increased peak trunk flexion and increased activation of the vastus lateralis, biceps femoris (BF) and gluteus maximus (GMax) during the landing phase. After the fatigue protocol, an increase in peak trunk flexion and activation of the GMax and BF were observed, most likely as a strategy to reduce the load on the ACL. ACL injury prevention programs should include strength and endurance exercises for the hip and trunk extensor muscles so that they can efficiently control trunk flexion during landing. Prospective comparative study, Level II.

  19. Heart Health - Brave Heart

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Brave Heart Past Issues / Winter 2009 Table of Contents For ... you can have a good life after a heart attack." Lifestyle Changes Surviving—and thriving—after such ...

  20. Effect of speed endurance training and reduced training volume on running economy and single muscle fiber adaptations in trained runners

    DEFF Research Database (Denmark)

    Skovgaard, Casper; Christiansen, Danny; Christensen, Peter Møller

    2018-01-01

    The aim of the present study was to examine whether improved running economy with a period of speed endurance training and reduced training volume could be related to adaptations in specific muscle fibers. Twenty trained male (n = 14) and female (n = 6) runners (maximum oxygen consumption (VO2 -max...... was performed. In addition, running at 60% vVO2 -max, and a 10-km run was performed in a normal and a muscle slow twitch (ST) glycogen-depleted condition. After compared to before the intervention, expression of mitochondrial uncoupling protein 3 (UCP3) was lower (P ....05) in ST muscle fibers, and sarcoplasmic reticulum calcium ATPase 1 (SERCA1) was lower (P VO2 -max (11.6 ± 0.2 km/h) and at v10-km (13.7 ± 0.3 km/h) was ~2% better (P

  1. Effect of a single oral dose of milrinone on left ventricular diastolic performance in the failing human heart

    NARCIS (Netherlands)

    F. Piscione; B.E. Jaski; G.J. Wenting (Gert); P.W.J.C. Serruys (Patrick)

    1987-01-01

    textabstractIn 14 patients with severe congestive heart failure, left ventricular pressure (measured by tip manometer) and derived variables were measured before and every 10 minutes after administration of oral milrinone (10 mg) for 50 minutes along with measurements of coronary sinus blood flow

  2. Quantification of early fatty infiltration of the rotator cuff muscles: comparison of multi-echo Dixon with single-voxel MR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Agten, Christoph A.; Rosskopf, Andrea B.; Pfirrmann, Christian W.A. [Balgrist University Hospital, Radiology, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland); Gerber, Christian [Balgrist University Hospital, Orthopaedic Surgery, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland)

    2016-10-15

    To evaluate quantification of early fatty infiltration in supraspinatus muscles with magnetic resonance (MR) imaging using a T2*-corrected multi-echo 3D-gradient-echo Dixon-based sequence (multi-echo Dixon) and compare it to proton-MR-spectroscopy. Sixty subjects (mean age 46 years, 41 men) with good supraspinatus muscle quality on 1.5 T MR imaging were included. Fat percentage (FP) in the supraspinatus muscle was quantified using a multi-echo Dixon compared to single-voxel MR spectroscopy as reference standard. In 18 subjects the multi-echo Dixon was repeated to assess test-retest reliability. Measurements based on multi-echo Dixon were performed by two independent readers by placing regions-of-interest (ROIs) in the supraspinatus muscle corresponding to the MR-spectroscopy voxel. Intraclass and concordance correlation coefficients (ICC/CCC) were used for statistical analysis. Test-retest reliability was substantial for reader 1 (ICC = 0.757) and almost perfect for reader 2 (ICC = 0.873). Inter-reader reliability for multi-echo Dixon was almost perfect (ICC = 0.893, P <.0005). Mean FP in all 60 subjects with multi-echo Dixon was 3.5 ± 1.6 for reader 1, 3.7 ± 1.8 for reader 2, and 2.8 ± 1.4 with MR spectroscopy. Correlation between multi-echo Dixon and MR spectroscopy was moderate (CCC = 0.641). The multi-echo Dixon sequence is a reliable method and comparable to MR-spectroscopy for quantification of low levels of fatty infiltration in the supraspinatus muscle. (orig.)

  3. Imaging of muscle injuries

    Energy Technology Data Exchange (ETDEWEB)

    El-Khoury, G.Y. [Iowa Univ., Iowa City, IA (United States). Dept. of Radiology; Brandser, E.A. [Iowa Univ., Iowa City, IA (United States). Dept. of Radiology; Kathol, M.H. [Iowa Univ., Iowa City, IA (United States). Dept. of Radiology; Tearse, D.S. [Iowa Univ., Iowa City, IA (United States). Dept. of Orthopaedic Surgery; Callaghan, J.J. [Iowa Univ., Iowa City, IA (United States). Dept. of Orthopaedic Surgery

    1996-01-01

    Although skeletal muscle is the single largest tissue in the body, there is little written about it in the radiologic literature. Indirect muscle injuries, also called strains or tears, are common in athletics, and knowing the morphology and physiology of the muscle-tendon unit is the key to the understanding of these injuries. Eccentric muscle activation produces more tension within the muscle tan when it is activated concentrically, making it more susceptible to tearing. Injuries involving the muscle belly tend to occur near the myotendinous junction. In adolescents, the weakest link in the muscle-tendon-bone complex is the apophysis. Traditionally, plain radiography has been the main diagnostic modality for evaluation of these injuries; however, with the advent of MRI it has become much easier to diagnose injuries primarily affecting the soft tissues. This article reviews the anatomy and physiology of the muscle-tendon unit as they relate to indirect muscle injuries. Examples of common muscle injuries are illustrated. (orig.)

  4. The Effect of Cleft Palate Repair on Contractile Properties of Single Permeabilized Muscle Fibers From Congenitally Cleft Goats Palates

    Science.gov (United States)

    A cleft palate goat model was used to study the contractile properties of the levator veli palatini (LVP) muscle which is responsible for the movement of the soft palate. In 15-25% of patients that undergo palatoplasty, residual velopharyngeal insufficiency (VPI) remains a problem and often require...

  5. Spatial distribution of surface EMG on trapezius and lumbar muscles of violin and cello players in single note playing.

    Science.gov (United States)

    Afsharipour, Babak; Petracca, Francesco; Gasparini, Mauro; Merletti, Roberto

    2016-12-01

    Musicians activate their muscles in different patterns, depending on their posture, the instrument being played, and their experience level. Bipolar surface electrodes have been used in the past to monitor such activity, but this method is highly sensitive to the location of the electrode pair. In this work, the spatial distribution of surface EMG (sEMG) of the right trapezius and right and left erector spinae muscles were studied in 16 violin players and 11 cello players. Musicians played their instrument one string at a time in sitting position with/without backrest support. A 64 sEMG electrode (16×4) grid, 10mm inter-electrode distance (IED), was placed over the middle and lower trapezius (MT and LT) of the bowing arm. Two 16×2 electrode grids (IED=10mm) were placed on the left and right erector spinae muscles. Subjects played each of the four strings of the instrument either in large (1bow/s) or detaché tip/tail (8bows/s) bowing in two sessions (two days). In each of two days, measurements were repeated after half an hour of exercise to see the effect of exercise on the muscle activity and signal stability. A "muscle activity index" (MAI) was defined as the spatial average of the segmented active region of the RMS map. Spatial maps were automatically segmented using the watershed algorithm and thresholding. Results showed that, for violin players, sliding the bow upward from the tip toward the tail results in a higher MAI for the trapezius muscle than a downward bow. On the contrary, in cello players, higher MAI is produced in the tail to tip movement. For both instruments, an increasing MAI in the trapezius was observed as the string position became increasingly lateral, from string 1 (most medial) toward string 4 (most lateral). Half an hour of performance did not cause significant differences between the signal quality and the MAI values measured before and after the exercise. The MAI of the left and right erector spinae was smaller in the case of

  6. [Adenosine triphosphate stress 99mTc-MIBI single-photon emission computed tomography in the diagnosis of ischemic heart disease].

    Science.gov (United States)

    Karpova, I E; Samoĭlenko, L E; Soboleva, G N; Sergienko, V B; Karpov, Iu A

    2013-01-01

    This review is devoted to possibilities of single-photon emission computed tomography (SPECT) combined with pharmacological test with adenosine triphosphate (ATP) to detect myocardial ischemia in patients with ischemic heart disease (IHD). It contains consideration of contemporary problems and limitations inherent in use of pharmacological stress tests in radionuclide diagnostics; discussion of mechanisms of vasodilating effects of ATP in the context of modern concepts of purine receptors; detailed description of technique of pharmacological testing with ATP, as well as contraindications and possible side effects. Experience of foreign studies with the use of ATP stress testing for verification of presence of ischemia in patients with IHD is also presented.

  7. Berlin heart ventricular assist device as a long-term bridge to transplantation in a Fontan patient with failing single ventricle.

    Science.gov (United States)

    Halaweish, I; Ohye, R G; Si, M S

    2015-12-01

    The use of VADs as a BTT in children with heart failure has increased due to enhanced device design and reliability, leading to improved survival, functional capacity, and quality of life. However, the use of VADs in patients with Fontan physiology as a BTT is rare with few case reports. Here, we describe a case of implantation of the Berlin VAD as a BTT for 179 days, one of the longest reported periods of mechanical support, in a child with failing single ventricle. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. The acute effects of static stretching on peak force, peak rate of force development and muscle activity during single- and multiple-joint actions in older women.

    Science.gov (United States)

    Gonçalves, Raquel; Gurjão, André Luiz Demantova; Jambassi Filho, José Claudio; Farinatti, Paulo De Tarso Veras; Gobbi, Lilian Teresa Bucken; Gobbi, Sebastião

    2013-01-01

    The present study investigated the acute effects of static stretching on peak force, peak rate of force development and integrated electromyography (iEMG) in 27 older women (65 ± 4 years; 69 ± 9 kg; 157 ± 1 cm; 28 ± 4 kg · m(-2)). The participants were tested during two exercises (leg press and knee extension) after two conditions: stretching and control. The data were collected on four days (counterbalanced with a 24-hour rest period). In the stretching condition, the quadriceps muscle was stretched (knee flexion) for three sets of 30 s with 30 s rest intervals. No significant difference was detected for peak force and peak rate of force development during the single- and multiple-joint exercises, regardless of the following interactions: condition (stretching and control) vs. time (pre x post x 10 x 20 x 30 minutes post; P > 0.05) and exercise vs. time (P > 0.05). Additionally, no significant interaction was found for the iEMG activity (condition vs. time; P > 0.05) in the single- and multiple-joint exercises. In conclusion, a small amount of stretching of an agonist muscle (quadriceps) did not affect the peak force, peak rate of force development and EMG activity in older women during single- and multiple-joint exercises.

  9. The effects of acute experimental hip muscle pain on dynamic single-limb balance performance in healthy middle-aged adults.

    Science.gov (United States)

    Hatton, Anna L; Hug, François; Chen, Sarah H; Reid, Christine; Sorensen, Nicole A; Tucker, Kylie

    2016-10-01

    Middle-aged adults with painful hip conditions show balance impairments that are consistent with an increased risk of falls. Pathological changes at the hip, accompanied by pain, may accelerate pre-existing age-related balance deficits present in midlife. To consider the influence of pain alone, we investigated the effects of acute experimental hip muscle pain on dynamic single-limb balance in middle-aged adults. Thirty-four healthy adults aged 40-60 years formed two groups (Group-1: n=16; Group-2: n=18). Participants performed four tasks: Reactive Sideways Stepping (ReactSide); Star Excursion Balance Test (SEBT); Step Test; Single-Limb Squat; before and after an injection of hypertonic saline into the right gluteus medius muscle (Group-1) or ∼5min rest (Group-2). Balance measures included the range and standard deviation of centre of pressure (CoP) movement in mediolateral and anterior-posterior directions, and CoP total path velocity (ReactSide, Squat); reach distance (SEBT); and number of completed steps (Step Test). Data were assessed using three-way analysis of variance. Motor outcomes were altered during the second repetition of tasks irrespective of exposure to experimental hip muscle pain or rest, with reduced SEBT anterior reach (-1.2±4.1cm, P=0.027); greater step number during Step Test (1.5±1.7 steps, PCoP velocity during Single-Limb Squat (-4.9±9.4mms -1 , P=0.024). Factors other than the presence of pain may play a greater role in balance impairments in middle-aged adults with hip pathologies. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Effect of speed endurance training and reduced training volume on running economy and single muscle fiber adaptations in trained runners.

    Science.gov (United States)

    Skovgaard, Casper; Christiansen, Danny; Christensen, Peter M; Almquist, Nicki W; Thomassen, Martin; Bangsbo, Jens

    2018-02-01

    The aim of the present study was to examine whether improved running economy with a period of speed endurance training and reduced training volume could be related to adaptations in specific muscle fibers. Twenty trained male (n = 14) and female (n = 6) runners (maximum oxygen consumption (VO 2 -max): 56.4 ± 4.6 mL/min/kg) completed a 40-day intervention with 10 sessions of speed endurance training (5-10 × 30-sec maximal running) and a reduced (36%) volume of training. Before and after the intervention, a muscle biopsy was obtained at rest, and an incremental running test to exhaustion was performed. In addition, running at 60% vVO 2 -max, and a 10-km run was performed in a normal and a muscle slow twitch (ST) glycogen-depleted condition. After compared to before the intervention, expression of mitochondrial uncoupling protein 3 (UCP3) was lower (P < 0.05) and dystrophin was higher (P < 0.05) in ST muscle fibers, and sarcoplasmic reticulum calcium ATPase 1 (SERCA1) was lower (P < 0.05) in fast twitch muscle fibers. Running economy at 60% vVO 2 -max (11.6 ± 0.2 km/h) and at v10-km (13.7 ± 0.3 km/h) was ~2% better (P < 0.05) after the intervention in the normal condition, but unchanged in the ST glycogen-depleted condition. Ten kilometer performance was improved (P < 0.01) by 3.2% (43.7 ± 1.0 vs. 45.2 ± 1.2 min) and 3.9% (45.8 ± 1.2 vs. 47.7 ± 1.3 min) in the normal and the ST glycogen-depleted condition, respectively. VO 2 -max was the same, but vVO 2 -max was 2.0% higher (P < 0.05; 19.3 ± 0.3 vs. 18.9 ± 0.3 km/h) after than before the intervention. Thus, improved running economy with intense training may be related to changes in expression of proteins linked to energy consuming processes in primarily ST muscle fibers. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  11. Effect of stretching with and without muscle strengthening exercises for the foot and hip in patients with plantar fasciitis: A randomized controlled single-blind clinical trial.

    Science.gov (United States)

    Kamonseki, Danilo H; Gonçalves, Geiseane A; Yi, Liu C; Júnior, Império Lombardi

    2016-06-01

    To compare the effect of stretching with and without muscle strengthening of the foot alone or foot and hip on pain and function in patients with plantar fasciitis. Single blind randomized controlled trial. Eighty-three patients with plantar fasciitis were allocated to one of three treatment options for an eight-week period: Foot Exercise Group (FEG - extrinsic and intrinsic foot muscles), Foot and Hip Exercise Group (FHEG - abductor and lateral rotator muscles) and Stretching Alone Exercise Group (SAEG). A visual analog scale for pain, the Foot and Ankle Outcome Score and the Star Excursion Balance Test. All evaluations were performed before treatment and after the last treatment session. Improvements were found in all groups regarding the visual analog scale, the pain, activities of daily living, sports and recreation, quality of life (p  0.05). All three exercise protocols analyzed led to improvements at eight-week follow-up in pain, function and dynamic lower limb stability in patients with plantar fasciitis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Accumulation of Copper in Gill, Liver, Spleen, Kidney and Muscle Tissues of Clarias gariepinus Exposed to the Metal Singly and in Mixture with Chitosan.

    Science.gov (United States)

    Tunçsoy, Mustafa; Duran, Servet; Ay, Özcan; Cicik, Bedii; Erdem, Cahit

    2016-10-01

    Accumulation of copper (Cu), applied singly and in mixture with chitosan (CT), in gill, liver, spleen, kidney and muscle tissues of Clarias gariepinus was studied after exposing the fish to no Cu (control), 5 ppm Cu, 5 ppm Cu + 75 ppm CT mixture over 1, 7 and 15 days. Metal levels in tissues were determined using an ICP-AES spectrophotometer. No mortality was observed during the experiments. Highest accumulation of Cu was observed in liver while lowest accumulation was observed in muscle tissue. Exposure to Cu-CT mixture decreased Cu accumulation in liver at all exposure periods and in kidney on the 15th day compared to Cu alone. Exposure to Cu alone and Cu-CT mixture had no effect on Cu accumulation in spleen or muscle tissue. Copper accumulation increased in gill tissue compared to control when exposed to Cu alone at all exposure periods, and exposure to the Cu-CT mixture significantly increased Cu accumulation in this tissue at all exposure periods compared to Cu alone.

  13. Effect of cleft palate repair on the susceptibility to contraction-induced injury of single permeabilized muscle fibers from congenitally-clefted goat palates.

    Science.gov (United States)

    Rader, Erik P; Cederna, Paul S; McClellan, William T; Caterson, Stephanie A; Panter, Kip E; Yu, Deborah; Buchman, Steven R; Larkin, Lisa M; Faulkner, John A; Weinzweig, Jeffrey

    2008-03-01

    Despite cleft palate repair, velopharyngeal competence is not achieved in approximately 15% of patients, often necessitating secondary surgical correction. Velopharyngeal competence postrepair may require the conversion of levator veli palatini muscle fibers from injury-susceptible type 2 fibers to injury-resistant type 1 fibers. As an initial step to determining the validity of this theory, we tested the hypothesis that, in most cases, repair induces the transformation to type 1 fibers, thus diminishing susceptibility to injury. Single permeabilized levator veli palatini muscle fibers were obtained from normal palates and nonrepaired congenitally-clefted palates of young (2 months old) and adult (14 to 15 months old) goats and from repaired palates of adult goats (8 months old). Repair was done at 2 months of age using a modified von Langenbeck technique. Fiber type was determined by contractile properties and susceptibility to injury was assessed by force deficit, the decrease in maximum force following a lengthening contraction protocol expressed as a percentage of initial force. For normal palates and cleft palates of young goats, the majority of the fibers were type 2 with force deficits of approximately 40%. Following repair, 80% of the fibers were type 1 with force deficits of 20% +/- 2%; these deficits were 45% of those for nonrepaired cleft palates of adult goats (p < .0001). The decrease in the percentage of type 2 fibers and susceptibility to injury may be important for the development of a functional levator veli palatini muscle postrepair.

  14. A contemporary, single-institutional experience of surgical versus expectant management of congenital heart disease in trisomy 13 and 18 patients.

    Science.gov (United States)

    Costello, John P; Weiderhold, Allison; Louis, Clauden; Shaughnessy, Conner; Peer, Syed M; Zurakowski, David; Jonas, Richard A; Nath, Dilip S

    2015-06-01

    The objective of this study was to examine a large institutional experience of patients with trisomy 13 and trisomy 18 in the setting of comorbid congenital heart disease and present the outcomes of surgical versus expectant management. It is a retrospective single-institution cohort study. Institutional review board approved this study. Thirteen consecutive trisomy 18 patients and three consecutive trisomy 13 patients (sixteen patients in total) with comorbid congenital heart disease who were evaluated by our institution's Division of Cardiovascular Surgery between January 2008 and December 2013 were included in the study. The primary outcome measures evaluated were operative mortality (for patients who received surgical management), overall mortality (for patients who received expectant management), and total length of survival during follow-up. Of the thirteen trisomy 18 patients, seven underwent surgical management and six received expectant management. With surgical management, operative mortality was 29 %, and 80 % of patients were alive after a median follow-up of 116 days. With expectant management, 50 % of patients died before hospital discharge. Of the three patients with trisomy 13, one patient underwent surgical management and two received expectant management. The patient who received surgical management with complete repair was alive at last follow-up over 2 years after surgery; both patients managed expectantly died before hospital discharge. Trisomy 13 and trisomy 18 patients with comorbid congenital heart disease can undergo successful cardiac surgical intervention. In this population, we advocate that nearly all patients with cardiovascular indications for operative congenital heart disease intervention should be offered complete surgical repair over palliative approaches for moderately complex congenital cardiac anomalies.

  15. Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer

    OpenAIRE

    Thiele, Jan; Bannasch, Holger; Stark, G. Bjoern; Eisenhardt, Steffen U.

    2015-01-01

    Unilateral facial paralysis is a common disease that is associated with significant functional, aesthetic and psychological issues. Though idiopathic facial paralysis (Bell?s palsy) is the most common diagnosis, patients can also present with a history of physical trauma, infectious disease, tumor, or iatrogenic facial paralysis. Early repair within one year of injury can be achieved by direct nerve repair, cross-face nerve grafting or regional nerve transfer. It is due to muscle atrophy that...

  16. Red yeast rice induces less muscle fatigue symptom than simvastatin in dyslipidemic patients: a single center randomized pilot trial.

    Science.gov (United States)

    Xue, Yangjing; Tao, Luyuan; Wu, Shaoze; Wang, Guoqiang; Qian, Lu; Li, Jiwu; Liao, Lianming; Tang, Jifei; Ji, Kangting

    2017-05-18

    About 10-15% patients who take statins experience skeletal muscle problems. Red yeast rice has a good safety profile could provide a compromise therapeutic strategy. Therefore, the aim of this study was to evaluate the effects of red yeast rice, when compared to simvastatin, on the muscle fatigue symptom and the serum lipid level in dyslipidemic patients with low to moderate cardiovascular risk. A total of 60 dyslipidemic patients with low to moderate cardiovascular risk were recruited and randomly assigned to receive either simvastatin (n = 33) or red yeast rice (n = 27) for 4 weeks. The muscle fatigue score, the physical activity, the serum lipid profile and the safety profile were then evaluated. At the end of study, the fatigue score was significantly increased in patients treated with simvastatin, whereas no significant change was observed in patients receiving red yeast rice. In addition, the physical activity level was significantly decreased in patients from simvastatin group when compared to those from red yeast rice group. Similar lipid-lowering effects were observed in two groups. The safety profile was not affected after the treatments. Among dyslipidemic patients with low to moderate cardiovascular risk, red yeast rice induced less fatigue side effect and exerted comparable lipid-lowering effects when compared to simvastatin in this pilot primary prevention study. NCT01686451 .

  17. Robust and Accurate Closed-Loop Control of McKibben Artificial Muscle Contraction with a Linear Single Integral Action

    Directory of Open Access Journals (Sweden)

    Bertrand Tondu

    2014-06-01

    Full Text Available We analyze the possibility of taking advantage of artificial muscle’s own stiffness and damping, and substituting it for a classic proportional-integral-derivative controller (PID controller an I controller. The advantages are that there would only be one parameter to tune and no need for a dynamic model. A stability analysis is proposed from a simple phenomenological artificial muscle model. Step and sinus-wave tracking responses performed with pneumatic McKibben muscles are reported showing the practical efficiency of the method to combine accuracy and load robustness. In the particular case of the McKibben artificial muscle technology, we suggest that the dynamic performances in stability and load robustness would result from the textile nature of its braided sleeve and its internal friction which do not obey Coulomb’s third law, as verified by preliminary reported original friction experiments. Comparisons are reported between three kinds of braided sleeves made of rayon yarns, plastic, and thin metal wires, whose similar closed-loop dynamic performances are highlighted. It is also experimentally shown that a sleeve braided with thin metal wires can give high accuracy performance, in step as in tracking response. This would be due to a low static friction coefficient combined with a kinetic friction exponentially increasing with speed in accordance with hydrodynamic lubrication theory applied to textile physics.

  18. Skeletal muscle mass in hospitalized elderly patients: comparison of measurements by single-frequency BIA and DXA.

    Science.gov (United States)

    Bosaeus, Ingvar; Wilcox, Gisela; Rothenberg, Elisabet; Strauss, Boyd J

    2014-06-01

    There is increasing interest in estimating skeletal muscle mass (SMM) in clinical practice. We aimed to validate a bioelectrical impedance analysis (BIA) prediction equation for SMM, developed in a different healthy elderly population, in a population of hospital patients aged 70 and over, by comparison with dual-energy X-ray absorptiometry (DXA) SMM estimates. Comparison was also made with two other previously published BIA muscle prediction equations. Muscle measurements by BIA and DXA were compared in 117 patients with a range of clinical conditions (45 female, 72 male, mean age 75 years). The BIA equation used yielded an accurate estimate of DXA-derived SMM. Mean (SD) difference was 0.26(1.79) kg (ns). The two other BIA equations over-estimated SMM compared to DXA (both p equations were highly correlated. The BIA equation used, developed in a different healthy elderly population, gave an accurate estimate of DXA-derived SMM in a population with various clinical disorders. BIA appears potentially capable to estimate SMM in clinical disorders, but the optimal approach to its use for this purpose requires further investigation. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  19. The effect of short-term isometric muscle contraction and the Valsalva maneuver on systemic and pulmonary hemodynamics in patients with severe heart failure

    Czech Academy of Sciences Publication Activity Database

    Souček, M.; Fráňa, P.; Kára, J.; Sitar, J.; Halámek, Josef; Jurák, Pavel; Řiháček, I.; Špinarová, L.; Oral, I.

    2009-01-01

    Roč. 32, č. 6 (2009), E32-E39 ISSN 0160-9289 R&D Projects: GA ČR(CZ) GA102/05/0402 Institutional research plan: CEZ:AV0Z20650511 Keywords : leg muscle * muscle isometric contraction Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.602, year: 2009

  20. Spatial distribution of "tissue-specific" antigens in the developing human heart and skeletal muscle. I. An immunohistochemical analysis of creatine kinase isoenzyme expression patterns

    NARCIS (Netherlands)

    Wessels, A.; Vermeulen, J. L.; Virágh, S.; Kálmán, F.; Morris, G. E.; Man, N. T.; Lamers, W. H.; Moorman, A. F.

    1990-01-01

    Using monoclonal antibodies against the M and B subunit isoforms of creatine kinase (CK) we have investigated their distribution in developing human skeletal and cardiac muscle immunohistochemically. It is demonstrated that in skeletal muscle, a switch from CK-B to CK-M takes place around the week 8

  1. Dual-Axis Rotational Angiography is Safe and Feasible to Detect Coronary Allograft Vasculopathy in Pediatric Heart Transplant Patients: A Single-Center Experience.

    Science.gov (United States)

    Rios, Rodrigo; Loomba, Rohit S; Foerster, Susan R; Pelech, Andrew N; Gudausky, Todd M

    2016-04-01

    Coronary allograft vasculopathy (CAV) is the leading cause of graft failure in pediatric heart transplant recipients, also adding to mortality in this patient population. Coronary angiography is routinely performed to screen for CAV, with conventional single-plane or bi-plane angiography being utilized. Dual-axis rotational coronary angiography (RA) has been described, mostly in the adult population, and may offer reduction in radiation dose and contrast volume. Experience with this in the pediatric population is limited. This study describes a single-institution experience with RA for screening for CAV in pediatric patients. The catheterization database at our institution was used to identify pediatric heart transplant recipients having undergone RA to screen for CAV. Procedural data including radiation dose, fluoroscopy time, contrast volume, and procedure time were collected for each catheterization. The number of instances in which RA was not successful, ECG changes were present, and CAV was detected were also collected for each catheterization. A total of 97 patients underwent 345 catheterizations utilizing RA. Median radiation dose-area product per kilogram was found to be 341.7 (mGy cm(2)/kg), total air kerma was 126.8 (mGy), procedure time was 69 min, fluoroscopy time was 9.9 min, and contrast volume was 13 ml. A total of 17 (2 %) coronary artery injections out of 690 could not be successfully imaged using RA. A total of 14 patients had CAV noted at any point, 10 of whom had progressive CAV. Electrocardiographic changes were documented in a total of 10 (3 %) RA catheterizations. Procedural characteristics did not differ between serial catheterizations. RA is safe and feasible for CAV screening in pediatric heart transplant recipients while offering coronary imaging in multiple planes compared to conventional angiography.

  2. Predicting mortality after congenital heart surgeries: evaluation of the Aristotle and Risk Adjustement in Congenital Heart Surgery-1 risk prediction scoring systems: a retrospective single center analysis of 1150 patients.

    Science.gov (United States)

    Joshi, Shreedhar S; Anthony, G; Manasa, D; Ashwini, T; Jagadeesh, A M; Borde, Deepak P; Bhat, Seetharam; Manjunath, C N

    2014-01-01

    To validate Aristotle basic complexity and Aristotle comprehensive complexity (ABC and ACC) and risk adjustment in congenital heart surgery-1 (RACHS-1) prediction models for in hospital mortality after surgery for congenital heart disease in a single surgical unit. Patients younger than 18 years, who had undergone surgery for congenital heart diseases from July 2007 to July 2013 were enrolled. Scoring for ABC and ACC scoring and assigning to RACHS-1 categories were done retrospectively from retrieved case files. Discriminative power of scoring systems was assessed with area under curve (AUC) of receiver operating curves (ROC). Calibration (test for goodness of fit of the model) was measured with Hosmer-Lemeshow modification of χ2 test. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were applied to assess reclassification. A total of 1150 cases were assessed with an all-cause in-hospital mortality rate of 7.91%. When modeled for multivariate regression analysis, the ABC (χ2 = 8.24, P = 0.08), ACC (χ2 = 4.17 , P = 0.57) and RACHS-1 (χ2 = 2.13 , P = 0.14) scores showed good overall performance. The AUC was 0.677 with 95% confidence interval (CI) of 0.61-0.73 for ABC score, 0.704 (95% CI: 0.64-0.76) for ACC score and for RACHS-1 it was 0.607 (95%CI: 0.55-0.66). ACC had an improved predictability in comparison to RACHS-1 and ABC on analysis with NRI and IDI. ACC predicted mortality better than ABC and RCAHS-1 models. A national database will help in developing predictive models unique to our populations, till then, ACC scoring model can be used to analyze individual performances and compare with other institutes.

  3. [Improving of muscle mass and force in rehabilitation of heart-lung patients. Aerobic interval training, resistance-exercises, excentric exercises, vibration].

    Science.gov (United States)

    Apor, Péter; Tihanyi, József; Borka, Péter

    2005-09-18

    Improvement of muscle mass and force which got depleted by inactivity or pathological processes is one of the aims and also a prerequisite of a rehabilitative intervention. Metabolically active larger and stronger muscles diminish the cardiovascular risk, permit the aerobic preventive and rehabilitative activities and enables a higher quality of life. Interval forms of aerobic exercise improves also the muscles. The resistance training plays an important part in rehabilitation. Beside the traditional dynamic strength training with weights, gym machines, body weight etc. the excentric type of muscle activity potentiates higher muscle load with lesser energy consumption, therefore it is suitable in the case of smaller performance ability. Vibration of the whole body or parts of it by machines improves the co-activity of the motor units and results in force development with small metabolic involvement.

  4. The effect of different skin-ankle brace application pressures on quiet single-limb balance and electromyographic activation onset of lower limb muscles.

    Science.gov (United States)

    Papadopoulos, Emmanuel S; Nikolopoulos, Christos; Badekas, Athanasios; Vagenas, George; Papadakis, Stamatios A; Athanasopoulos, Spyros

    2007-09-12

    Several studies have been carried out in order to investigate the effect of ankle bracing on ankle joint function and performance. However, no study so far has examined the role of skin-brace interface pressure in neuromuscular control. The aim of this study was to investigate the effect of different skin-ankle brace interface pressures on quiet single limb balance and the electromyographic (EMG) activation sequence of four lower limb muscles. Thirty three male physical education students who volunteered to take part in the study were measured under three ankle brace conditions: i) without brace, ii) with brace and 30 kPa application pressure and iii) with brace and 60 kPa application pressure. Single limb balance (anteroposterior and mediolateral parameter) was assessed on the dominant lower limb, with open and closed eyes, on a force platform, simultaneously with the EMG recording of four lower lower limb muscles' (gastrocnemius, peroneus longus, rectus femoris and biceps femoris) activation onset. The results showed that overall balance (total stability parameter) was not significantly affected in any of the three ankle brace conditions. However, the anteroposterior centre of pressure excursion and centre of pressure excursion velocity were significantly increased with the application of ankle brace, both with 30 and 60 kPa application pressures. Furthermore, it was found that single limb balance was significantly worse with closed eyes compared to open eyes. EMG measurements showed that the sequence of lower limb activation onset was not affected in any of the three ankle brace application conditions. The results of this study showed that the application of an ankle brace with two different skin-brace interface pressures had no effect on overall single limb balance and the sequence of lower limb muscle activation. These findings suggest that peripheral joint receptors are either not adequately stimulated by the brace application and therefore are not able to

  5. The effect of different skin-ankle brace application pressures on quiet single-limb balance and electromyographic activation onset of lower limb muscles

    Directory of Open Access Journals (Sweden)

    Papadakis Stamatios A

    2007-09-01

    Full Text Available Abstract Background Several studies have been carried out in order to investigate the effect of ankle bracing on ankle joint function and performance. However, no study so far has examined the role of skin-brace interface pressure in neuromuscular control. The aim of this study was to investigate the effect of different skin-ankle brace interface pressures on quiet single limb balance and the electromyographic (EMG activation sequence of four lower limb muscles. Methods Thirty three male physical education students who volunteered to take part in the study were measured under three ankle brace conditions: i without brace, ii with brace and 30 kPa application pressure and iii with brace and 60 kPa application pressure. Single limb balance (anteroposterior and mediolateral parameter was assessed on the dominant lower limb, with open and closed eyes, on a force platform, simultaneously with the EMG recording of four lower lower limb muscles' (gastrocnemius, peroneus longus, rectus femoris and biceps femoris activation onset. Results The results showed that overall balance (total stability parameter was not significantly affected in any of the three ankle brace conditions. However, the anteroposterior centre of pressure excursion and centre of pressure excursion velocity were significantly increased with the application of ankle brace, both with 30 and 60 kPa application pressures. Furthermore, it was found that single limb balance was significantly worse with closed eyes compared to open eyes. EMG measurements showed that the sequence of lower limb activation onset was not affected in any of the three ankle brace application conditions. The results of this study showed that the application of an ankle brace with two different skin-brace interface pressures had no effect on overall single limb balance and the sequence of lower limb muscle activation. Conclusion These findings suggest that peripheral joint receptors are either not adequately

  6. Monitoring of allograft vasculopathy by intravascular ultrasound one month and one year after heart transplantation: A single center study.

    Science.gov (United States)

    Bedanova, Helena; Orban, Marek; Tretina, Martin; Fila, Petr; Horvath, Vladimir; Krejci, Jan; Nemec, Petr

    2016-03-01

    The aim of this trial was to use intravascular ultrasound (IVUS) to determine whether cardiac allograft vasculopathy (CAV) starts progressing during the first year after heart transplantation (HTx). We retrospectively analyzed 51 patients (11 women) who received heart transplants in our center between January 2010 and September 2013 and underwent coronary angiography as well as IVUS examination one month and one year after HTx. Patients with proven calcification and fibrotic plates in the IVUS examination one month after HTx constituted a group with defined donor-transmitted atherosclerosis (DTA). In patients without DTA, measurements of maximal intimal thickening (MIT) were made in two predetermined locations. Eight of the 51 patients had DTA, while 43 did not. These were divided based on maximal intimal thickness (MIT) into a group with MIT first year after HTx significantly more frequently in patients with DTA and MIT ≥ 0.5 mm. It is essential in these patients to implement an IVUS control examination one year after transplantation. The results can lead to a change in treatment strategy to prevent further progress of the disease.

  7. A single exposure to acrolein causes arrhythmogenesis, cardiac electrical dysfunction and decreased heart rate variability in hypertensive rats

    Science.gov (United States)

    Epidemiological studies demonstrate an association between cardiovascular morbidity, arrhythmias, and exposure to air toxicants such as acrolein. We hypothesized that a single exposure to acrolein would increase arrhythmias and cause changes in the electrocardiogram (ECG) of hype...

  8. Heart murmurs

    Science.gov (United States)

    Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur ... The heart has 4 chambers: Two upper chambers (atria) Two lower chambers (ventricles) The heart has valves that close ...

  9. The role of the heart team in complicated transcatheter aortic valve implantation: a 7-year single-centre experience.

    Science.gov (United States)

    Kiefer, Philipp; Seeburger, Jörg; Noack, Thilo; Schröter, Thomas; Linke, Axel; Schuler, Gerhard; Haensig, Martin; Vollroth, Marcel; Mohr, Friedrich-Wilhelm; Holzhey, David Michael

    2015-06-01

    European guidelines recommend to perform transcatheter aortic valve implantation (TAVI) within a multidisciplinary heart team. However, there is a strong drive--despite existing guidelines--to perform TAVI outside of specialized centres. The aim of this study was to clarify the necessity of on-site cardiac surgery by providing a clear insight into the complications during/after TAVI that needed surgical management. A total of 2287 (1523 transfemoral, 752 transapical and 12 transaortic) patients, with a mean age of 84.5 ± 5.3 years, and a mean log EuroSCORE of 21.7 ± 16.3, of which 205 were female (84%), underwent TAVI since February 2006 at our institution. All procedure-related complications that required surgical interventions, whether immediate or delayed but within the initial hospital stay, were recorded and retrospectively analysed. Out of this cohort, 245 (10.7%) patients required surgical treatment due to major complications. A total of 42 patients (1.8%) underwent conversion to full sternotomy and 27 (1.2%) were dependent on the short-term use of the heart-lung machine. Vascular complications with surgical intervention were seen in 85 patients (3.7%), 54 patients (2.4%) had to have a rethoracotomy within their initial stay and 15 (0.7%) required a cardiac reoperation. Severe complications during TAVI that can only be resolved surgically will continue to occur. Therefore, each TAVI procedure should be conducted or accompanied by a cardiac surgeon and an experienced team within a specialized centre. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  10. Single molecule fluorescence image patterns linked to dipole orientation and axial position: application to myosin cross-bridges in muscle fibers.

    Directory of Open Access Journals (Sweden)

    Thomas P Burghardt

    2011-02-01

    Full Text Available Photoactivatable fluorescent probes developed specifically for single molecule detection extend advantages of single molecule imaging to high probe density regions of cells and tissues. They perform in the native biomolecule environment and have been used to detect both probe position and orientation.Fluorescence emission from a single photoactivated probe captured in an oil immersion, high numerical aperture objective, produces a spatial pattern on the detector that is a linear combination of 6 independent and distinct spatial basis patterns with weighting coefficients specifying emission dipole orientation. Basis patterns are tabulated for single photoactivated probes labeling myosin cross-bridges in a permeabilized muscle fiber undergoing total internal reflection illumination. Emitter proximity to the glass/aqueous interface at the coverslip implies the dipole near-field and dipole power normalization are significant affecters of the basis patterns. Other characteristics of the basis patterns are contributed by field polarization rotation with transmission through the microscope optics and refraction by the filter set. Pattern recognition utilized the generalized linear model, maximum likelihood fitting, for Poisson distributed uncertainties. This fitting method is more appropriate for treating low signal level photon counting data than χ(2 minimization.Results indicate that emission dipole orientation is measurable from the intensity image except for the ambiguity under dipole inversion. The advantage over an alternative method comparing two measured polarized emission intensities using an analyzing polarizer is that information in the intensity spatial distribution provides more constraints on fitted parameters and a single image provides all the information needed. Axial distance dependence in the emission pattern is also exploited to measure relative probe position near focus. Single molecule images from axial scanning fitted

  11. Risk stratifying chest pain patients in the emergency department using HEART, GRACE and TIMI scores, with a single contemporary troponin result, to predict major adverse cardiac events.

    Science.gov (United States)

    Reaney, Peter D W; Elliot, Hamish I; Noman, Awsan; Cooper, Jamie G

    2018-04-05

    The majority of patients presenting to the ED with cardiac sounding chest pain have a non-diagnostic ECG and the problem of differentiating those suffering an acute coronary syndrome from those without is familiar to all ED clinical staff. To stratify risk in these patients, specific scores have been developed. Recent work has focused on incorporating newer high-sensitivity cardiac troponin (hs-cTn) assays; however, issues regarding performance and availability of these assays remain. Prospectively compare HEART, Global Registry of Acute Coronary Events (GRACE) and Thrombolysis in Myocardial Infarction (TIMI) scores, using a single contemporary cTn at admission, to predict a major adverse cardiac event (MACE) at 30 days. Prospective observational cohort study performed in a UK tertiary hospital in patients with suspected cardiac chest pain and no significant ST elevation on initial ECG. Data collection took place 2 December 2014 to 8 February 2016. The treating clinician recorded risk score data real time and a single contemporary cTn taken at presentation was used in score calculation. The primary endpoint was 30-day MACE. C-statistic was determined for each score and diagnostic characteristics of high-risk and low-risk cut-offs were calculated. 189/1000 patients in the study developed a 30-day MACE. The c-statistic of HEART for 30-day MACE (0.87 (95% CI 0.84 to 0.90)) was higher than TIMI (0.78 (95% CI 0.74 to 0.81)) and GRACE (0.74 (95% CI 0.70 to 0.78)).HEART score ≤3 identified low-risk patients with sensitivity 99.5% (95% CI 97.1% to 99.9%) and negative predictive value (NPV) 99.6% (95% CI 97.3% to 99.9%) exceeding TIMI 0 (sensitivity 97.4% (95% CI 93.9% to 99.1%) and NPV 97.8% (95% CI 94.8% to 99.1%)) and GRACE score 0-55 (sensitivity 95.2% (95% CI 91.1% to 97.8%) and NPV 95.8% (95% CI 92.2% to 97.7%)). HEART outperformed both TIMI and GRACE in overall discriminative capacity for 30-day MACE. Using a single contemporary cTn at presentation, a HEART score

  12. Relationship between lung-to-heart uptake ratio of technetium-99m-tetrofosmin during exercise myocardial single photon emission computed tomographic imaging and the number of diseased coronary arteries in patients with effort angina pectoris without myocardial infarction

    International Nuclear Information System (INIS)

    Okajima, Toshiya; Ueshima, Kenji; Nishiyama, Osamu; Ogawa, Muneyoshi; Ohuchi, Mami; Saitoh, Masahiko; Hiramori, Katsuhiko

    2004-01-01

    Increased lung uptake of thallium-201 in exercise myocardial perfusion imaging is a reliable marker of multivessel disease in patients with ischemic heart disease. This study investigated whether the lung-to-heart uptake ratio with technetium-99m ( 99m Tc)-tetrofosmin also provides valuable information to detect patients with multivessel disease. Fifty-three consecutive patients (35 men, 18 women, mean age 66±11 years; single-vessel disease: 29, double-vessel disease: 16, triple-vessel disease: 8) with stable effort angina pectoris without prior myocardial infarction and 17 control subjects (12 men, 5 women, mean age 62±9 years) underwent exercise myocardial perfusion imaging with 99m Tc-tetrofosmin and coronary angiography in January 2000 to December 2002. The lung-to-heart uptake ratio was calculated on an anterior projection before reconstruction of the exercise single photon emission computed tomographic images. The mean lung-to-heart uptake ratio was 0.34±0.04, 0.38±0.07, 0.41±0.05, and 0.46±0.09, in patients with normal coronary, single-vessel disease, double-vessel disease, and triple-vessel disease, respectively. Significantly higher lung-to-heart uptake ratio was associated with more diseased vessels (p 99m Tc-tetrofosmin can provide clinically useful information to detect multivessel disease in patients with ischemic heart disease. (author)

  13. Prenatal diagnosis and risk factors for preoperative death in neonates with single right ventricle and systemic outflow obstruction: screening data from the Pediatric Heart Network Single Ventricle Reconstruction Trial(∗).

    Science.gov (United States)

    Atz, Andrew M; Travison, Thomas G; Williams, Ismee A; Pearson, Gail D; Laussen, Peter C; Mahle, William T; Cook, Amanda L; Kirsh, Joel A; Sklansky, Mark; Khaikin, Svetlana; Goldberg, Caren; Frommelt, Michele; Krawczeski, Catherine; Puchalski, Michael D; Jacobs, Jeffrey P; Baffa, Jeanne M; Rychik, Jack; Ohye, Richard G

    2010-12-01

    The purpose of this analysis was to assess preoperative risk factors before the first-stage Norwood procedure in infants with hypoplastic left heart syndrome and related single-ventricle lesions and to evaluate practice patterns in prenatal diagnosis, as well as the role of prenatal diagnosis in outcome. Data from all live births with morphologic single right ventricle and systemic outflow obstruction screened for the Pediatric Heart Network's Single Ventricle Reconstruction Trial were used to investigate prenatal diagnosis and preoperative risk factors. Demographics, gestational age, prenatal diagnosis status, presence of major extracardiac congenital abnormalities, and preoperative mortality rates were recorded. Of 906 infants, 677 (75%) had prenatal diagnosis, 15% were preterm (<37 weeks' gestation), and 16% were low birth weight (<2500 g). Rates of prenatal diagnosis varied by study site (59% to 85%, P < .0001). Major extracardiac congenital abnormalities were less prevalent in those born after prenatal diagnosis (6% vs 10%, P = .03). There were 26 (3%) deaths before Norwood palliation; preoperative mortality did not differ by prenatal diagnosis status (P = .49). In multiple logistic regression models, preterm birth (P = .02), major extracardiac congenital abnormalities (P < .0001), and obstructed pulmonary venous return (P = .02) were independently associated with preoperative mortality. Prenatal diagnosis occurred in 75%. Preoperative death was independently associated with preterm birth, obstructed pulmonary venous return, and major extracardiac congenital abnormalities. Adjusted for gestational age and the presence of obstructed pulmonary venous return, the estimated odds of preoperative mortality were 10 times greater for subjects with a major extracardiac congenital abnormality. Copyright © 2010 The American Association for Thoracic Surgery. All rights reserved.

  14. The effects of adding single-joint exercises to a multi-joint exercise resistance training program on upper body muscle strength and size in trained men.

    Science.gov (United States)

    de França, Henrique Silvestre; Branco, Paulo Alexandre Nordeste; Guedes Junior, Dilmar Pinto; Gentil, Paulo; Steele, James; Teixeira, Cauê Vazquez La Scala

    2015-08-01

    The aim of this study was compare changes in upper body muscle strength and size in trained men performing resistance training (RT) programs involving multi-joint plus single-joint (MJ+SJ) or only multi-joint (MJ) exercises. Twenty young men with at least 2 years of experience in RT were randomized in 2 groups: MJ+SJ (n = 10; age, 27.7 ± 6.6 years) and MJ (n = 10; age, 29.4 ± 4.6 years). Both groups trained for 8 weeks following a linear periodization model. Measures of elbow flexors and extensors 1-repetition maximum (1RM), flexed arm circumference (FAC), and arm muscle circumference (AMC) were taken pre- and post-training period. Both groups significantly increased 1RM for elbow flexion (4.99% and 6.42% for MJ and MJ+SJ, respectively), extension (10.60% vs 9.79%, for MJ and MJ+SJ, respectively), FAC (1.72% vs 1.45%, for MJ and MJ+SJ, respectively), and AMC (1.33% vs 3.17% for MJ and MJ+SJ, respectively). Comparison between groups revealed no significant difference in any variable. In conclusion, 8 weeks of RT involving MJ or MJ+SJ resulted in similar alterations in muscle strength and size in trained participants. Therefore, the addition of SJ exercises to a RT program involving MJ exercises does not seem to promote additional benefits to trained men, suggesting MJ-only RT to be a time-efficient approach.

  15. A Phase I, Single Ascending Dose Study of Cimaglermin Alfa (Neuregulin 1β3 in Patients With Systolic Dysfunction and Heart Failure

    Directory of Open Access Journals (Sweden)

    Daniel J. Lenihan, MD

    2016-12-01

    Full Text Available A first-in-human, phase 1, double blind, placebo-controlled, single ascending dose study examined the safety, tolerability, and exploratory efficacy of intravenous infusion of a recombinant growth factor, cimaglermin alfa, in patients with heart failure and left ventricular systolic dysfunction (LVSD. In these patients on optimal guideline-directed medical therapy, cimaglermin treatment was generally tolerated except for transient nausea and headache and a dose-limiting toxicity was noted at the highest planned dose. There was a dose-dependent improvement in left ventricular ejection fraction lasting 90 days following infusion. Thus, cimaglermin is a potential therapy to enhance cardiac function in LVSD and warrants further investigation.

  16. Development of a new Xe-133 single dose multi-step method (SDMM) for muscle blood flow measurement using gamma camera

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Seto, Mikito; Taki, Junichi

    1985-01-01

    In order to measure the muscle blood flow (MBF) during exercise (Ex), a new Xe-133 single dose multi-step method (SDMM) for leg MBF measurement before, during and after Ex using gamma camera was developped. Theoretically, if the activity of Xe-133 in the muscle immediately before and after Ex are known, then the mean MBF during Ex can be calculated. In SDMM, these activities are corrected through correction formula using time delays between end of data aquisition (DA) at rest (R1) and begining of the Ex (TAB), and between end of Ex and begining of the DA after Ex (R2) (TDA). Validity of the SDMM and MBF response on mild and heavy Ex were evaluated in 11 normal volunteers. Ex MBF calculated from 5 and 2.5 min DA (5 sec/frame) both at R1 and R2 were highly correlated (r=.996). Ex MBF by SDMM and direct(measurement by fixed leg exercise were also highly correlated (r=.999). Reproducibility of the R1 and Ex MBF were excellent (r=.999). The highest MBF was seen in GCM on miled walking Ex and in VLM on heavy squatting Ex. After miled Ex, MBF rapidly returned to normal. After heavy Ex, MBF remaind high in VLM In conclusion, SDMM is simple and accurate method for evaluation of dynamic MBF response according to exercise. SDMM is also applicable to the field of sports medicine. (author)

  17. The evaluation of modified foot orthosis on muscle activity and kinetic in a subject with flexible flat foot : single case study.

    Science.gov (United States)

    Saeedi, Hassan; Mousavi, Mohammad E; Majddoleslam, Basir; Rahgozar, Mehdi; Aminian, Gholamreza; Tabatabai Ghomshe, Farhad; Movahedi Yeganeh, Mohsen

    2014-04-01

    Due to blocking of pronation/dorsiflexion in flexible flat foot and restriction of these movements in using the University of California Berkeley Laboratory orthosis, provided pressures in sole by the orthosis were increased. Therefore, this article describes the evaluation of modified foot orthosis with flexible structure in the management of individuals with flexible flat foot. CASE DESCRIPTION AND METHOD: The patient was a 21-year-old male who had symptomatic flat foot. The modified foot orthosis included movable surface and the outside structure. The modified foot orthosis was evaluated by standing foot X-ray, comfort rate, electromyography of leg muscle and vertical ground reaction force during walking. The modified foot orthosis improved the foot alignment and decreased the symptoms of flat foot with more comfort. Subtalar position by sub-maximum supination had higher position than neutral in sagittal plane. It may increase the muscle activity of peroneus longus by 7% compared to barefoot, and there was a decrease of 11% ground reaction force in mid stance. The result of this single case evaluation only proposed the feasibility of this modified insole as the orthotic treatment in flexible flat foot. Clinical relevance The modified foot orthosis, which is mobile in the midfoot, is an orthosis for walking and standing in subjects with flexible flat foot.

  18. Evaluation of the SIPAT instrument to assess psychosocial risk in heart transplant candidates: A retrospective single center study.

    Science.gov (United States)

    Vandenbogaart, Elizabeth; Doering, Lynn; Chen, Belinda; Saltzman, Ann; Chaker, Tamara; Creaser, Julie W; Rourke, Darlene; Cheng, Richard W; Fonarow, Gregg C; Deng, Mario

    We evaluated the reliability of the Stanford Integrated Psychosocial Assessment for Transplantation (SIPAT) in heart transplant (HT) recipients and explored its usefulness in predicting post-transplant outcomes. Pre-transplant psychosocial and behavioral risk is associated with post-transplant clinical outcomes. SIPAT is a risk assessment tool created for pre-transplant psychosocial evaluation. Via retrospective chart review, three examiners applied the SIPAT to 51 adult HT recipients. Examiners blinded to SIPAT scores extracted data and interviewed clinicians for one-year post-transplant outcomes. Analysis included Intra-class correlation coefficient (ICC), Pearson's correlation coefficient and Chi-square. SIPAT demonstrated strong inter-rater reliability (ICC = 0.89, 95% CI = 0.76-0.96). Compared to those with SIPAT ratings of "Excellent/Good", the "Minimally Acceptable Candidate/High Risk" group was more likely to miss clinic visits (p = 0.004). The SIPAT tool had strong IRR. Less favorable SIPAT ratings were associated with nonadherence to clinic visits. Further study is warranted to determine association of SIPAT ratings to clinical outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. New Trends in Heart Regeneration: A Review

    Directory of Open Access Journals (Sweden)

    Kochegarov A

    2016-11-01

    Full Text Available In this review, we focus on new approaches that could lead to the regeneration of heart muscle and the restoration of cardiac muscle function derived from newly-formed cardiomyocytes. Various strategies for the production of cardiomyocytes from embryonic stem cells, induced pluripotent stem cells, adult bone marrow stem cells and cardiac spheres from human heart biopsies are described. Pathological conditions which lead to atherosclerosis and coronary artery disease often are followed by myocardial infarction causing myocardial cell death. After cell death, there is very little self-regeneration of the cardiac muscle tissue, which is replaced by non-contractile connective tissue, thus weakening the ability of the heart muscle to contract fully and leading to heart failure. A number of experimental research approaches to stimulate heart muscle regeneration with the hope of regaining normal or near normal heart function in the damaged heart muscle have been attempted. Some of these very interesting studies have used a variety of stem cell types in combination with potential cardiogenic differentiation factors in an attempt to promote differentiation of new cardiac muscle for possible future use in the clinical treatment of patients who have suffered heart muscle damage from acute myocardial infarctions or related cardiovascular diseases. Although progress has been made in recent years relative to promoting the differentiation of cardiac muscle tissue from non-muscle cells, much work remains to be done for this technology to be used routinely in translational clinical medicine to treat patients with damaged heart muscle tissue and return such individuals to pre-heart-attack activity levels.

  20. Novel single base-pair deletion in exon 1 of XK gene leading to McLeod syndrome with chorea, muscle wasting, peripheral neuropathy, acanthocytosis and haemolysis.

    Science.gov (United States)

    Wiethoff, Sarah; Xiromerisiou, Georgia; Bettencourt, Conceição; Kioumi, Anna; Tsiptsios, Iakovos; Tychalas, Athanasios; Evaggelia, Markousi; George, Kaltsounis; Makris, Vasileios; Hardy, John; Houlden, Henry

    2014-04-15

    We present a 70-year-old male patient of Greek origin with choreatic movements of the tongue and face, lower limb muscle weakness, peripheral neuropathy, elevated creatinephosphokinase (CPK), acanthocytosis and haemolysis in the absence of Kell RBC antigens with an additional Factor IX-deficiency. Genetic testing for mutations in the three exons of the XK gene revealed a previously unreported hemizygous single base-pair frameshift deletion at exon 1 (c.229delC, p.Leu80fs). In conclusion, we hereby describe a rare phenotype of a patient with McLeod syndrome which was discovered coincidentally during routine blood group testing and consecutively genetically confirmed. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  1. The Magnitude of Peripheral Muscle Fatigue Induced by High and Low Intensity Single-Joint Exercise Does Not Lead to Central Motor Output Reductions in Resistance Trained Men.

    Directory of Open Access Journals (Sweden)

    Paul W M Marshall

    Full Text Available To examine quadriceps muscle fatigue and central motor output during fatiguing single joint exercise at 40% and 80% maximal torque output in resistance trained men.Ten resistance trained men performed fatiguing isometric knee extensor exercise at 40% and 80% of maximal torque output. Maximal torque, rate of torque development, and measures of central motor output and peripheral muscle fatigue were recorded at two matched volumes of exercise, and after a final contraction performed to exhaustion. Central motor output was quantified from changes in voluntary activation, normalized surface electromyograms (EMG, and V-waves. Quadriceps muscle fatigue was assessed from changes in the size and shape of the resting potentiated twitch (Q.(pot.tw. Central motor output during the exercise protocols was estimated from EMG and interpolated twitches applied during the task (VA(sub.Greater reductions in maximal torque and rate of torque development were observed during the 40% protocol (p<0.05. Maximal central motor output did not change for either protocol. For the 40% protocol reductions from pre-exercise in rate and amplitude variables calculated from the Q.(pot.tw between 66.2 to 70.8% (p<0.001 exceeded those observed during the 80% protocol (p<0.01. V-waves only declined during the 80% protocol between 56.8 ± 35.8% to 53.6 ± 37.4% (p<0.05. At the end of the final 80% contraction VA(sub had increased from 91.2 ± 6.2% to 94.9 ± 4.7% (p = 0.005, but a greater increase was observed during the 40% contraction where VA(sub had increased from 67.1 ± 6.1% to 88.9 ± 9.6% (p<0.001.Maximal central motor output in resistance trained men is well preserved despite varying levels of peripheral muscle fatigue. Upregulated central motor output during the 40% contraction protocol appeared to elicit greater peripheral fatigue. V-waves declines during the 80% protocol suggest intensity dependent modulation of the Ia afferent pathway.

  2. Effect of a Single Administration of Focused Extracorporeal Shock Wave in the Relief of Delayed-Onset Muscle Soreness: Results of a Partially Blinded Randomized Controlled Trial.

    Science.gov (United States)

    Fleckenstein, Johannes; Friton, Mara; Himmelreich, Heiko; Banzer, Winfried

    2017-05-01

    To examine the effects of a single administration of focused extracorporeal shock wave therapy on eccentric exercise-induced delayed-onset muscle soreness (DOMS). Three-arm randomized controlled study. University research center. Participants (N=46; 23 women) had a mean age of 29.0±3.0 years and a mean body mass index of 23.8±2.8kg/m 2 . Participants were randomly allocated to verum- (energy flux density, .06-.09mJ/mm 2 ; pulse ratio per point, 200) or sham-focused extracorporeal shock wave therapy (no energy) at 7 equidistant points along the biceps muscle or no intervention. The primary outcome was the difference in pain intensity. Secondary outcomes included maximum isometric voluntary force (MIVF), pressure pain threshold (PPT), and impairment in daily life. Despite descriptive clinically meaningful differences, mixed-effects analysis (group × time) of changes to baseline did not reveal significant differences in the reduction of pain intensity between groups (F 2,42 =2.5, P=.094). MIVF was not significantly different between groups (F 2,43 =1.9, P=.159). PTT (F 2,43 =0.2, P=.854) and daily life impairment (F 2,42 =1.4, P=.248) were not significantly decreased over time, and there were no differences between groups in the post hoc analysis. DOMS is a common symptom in people participating in exercise, sports, or recreational physical activities. A single treatment with focused extracorporeal shock wave therapy causes clinically relevant effects in the relief of pain, increase in force, and improvement of pain-associated impairments of daily living. Still, results need to be cautiously interpreted because of the pilot character of this study. Focused extracorporeal shock wave therapy might present an option in the midterm recovery from DOMS (72h) and be an approach to enhance the return to play in athletes. Copyright © 2017. Published by Elsevier Inc.

  3. Expression of the skeletal calsequestrin isoform in normal and regenerated skeletal muscles and in the hearts of rats with altered thyroid status

    Czech Academy of Sciences Publication Activity Database

    Soukup, Tomáš; Sulimenko, Vadym; Marková, Vladimíra; Kopecká, Kateřina; Zachařová, Gisela; Paleček, Jiří

    2012-01-01

    Roč. 61, č. 6 (2012), s. 575-586 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA304/08/0256; GA ČR(CZ) GA305/09/1228; GA ČR(CZ) GBP304/12/G069 Grant - others:EC(XE) Myores 511978 Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z50520701 Institutional support: RVO:67985823 ; RVO:68378050 Keywords : skeletal calsequestrin * calcium and muscle contraction * thyroid hormones * western blot and qRT-PCR analysis * muscle transplantation * fast and slow muscle fibers Subject RIV: EA - Cell Biology Impact factor: 1.531, year: 2012

  4. Ethnical Variations in the Incidence of Congenital Heart Defects in Gorgan, Northern Iran: A Single-Center Study

    Directory of Open Access Journals (Sweden)

    Bagher Nikyar

    2015-10-01

    Full Text Available Background: Congenital heart disease (CHD is the most common congenital anomaly in newborns. This study was performed to determine the live birth incidence of CHD by ethnicity and sex in Gorgan, Northern Iran.Methods: In this longitudinal, hospital-based study, 18162 live births in Dezyani Hospital in Gorgan, North of Iran, were screened for CHD, from 2007 through 2009. Clinical examination, echocardiography, color Doppler, and cardio catheterization were used as diagnostic tools. Sex, ethnicity, and type of CHD for each case were recorded in a pre-designed questionnaire.Results: The incidence rates of CHD in the native Fars, Sistani, and Turkmen subjects were 5.73 (95%CI: 4.53-7.15,12.27 (95%CI: 8.74-16.73, and 15.93 (95%CI: 10.00-24.02 per 1000 live births, respectively. The Turkmen to native Fars and Sistani to native Fars relative risk for congenital CHD malformations was 2.77 (95%CI: 1.73-4.44; p value < 0.001 and 1.29 (95%CI: 0.77-2.18; p value < 0.323, respectively. While atrial septal defect was the most common lesion in the native Fars subjects (2.14 per 1000 [95%CI: 1.42-3.06] and in the Sistani subjects (2.84 per 1000 [95%CI: 1.29-5.36], in the Turkmen subjects, ventricular septal defect (4.36 per 1000 [95%CI: 1.59-9.43], followed by atrial septal defect, was the most frequent lesion.Conclusion: This study showed that the incidence and pattern of CHD among live births in Gorgan, North of Iran, varied according to ethnicity. The risk of CHD was higher in the Turkmen and Sistani groups than in the Fars population

  5. Comparison between the SAPIEN S3 and the SAPIEN XT transcatheter heart valves: A single-center experience.

    Science.gov (United States)

    Sawaya, Fadi J; Spaziano, Marco; Lefèvre, Thierry; Roy, Andrew; Garot, Phillippe; Hovasse, Thomas; Neylon, Antoinette; Benamer, Hakim; Romano, Mauro; Unterseeh, Thierry; Morice, Marie-Claude; Chevalier, Bernard

    2016-12-26

    To investigate the clinical outcomes of transcatheter aortic valve implantation (TAVI) with the SAPIEN 3 transcatheter heart valve (S3-THV) vs the SAPIEN XT valve (XT-THV). We retrospectively analyzed 507 patients that underwent TAVI with the XT-THV and 283 patients that received the S3-THV at our institution between March 2010 and December 2015. Thirty-day mortality (3.5% vs 8.7%; OR = 0.44, P = 0.21) and 1-year mortality (25.7% vs 20.1%, P = 0.55) were similar in the S3-THV and the XT-THV groups. The rates of both major vascular complication and paravalvular regurgitation (PVR) > 1 were almost 4 times lower in the S3-THV group than the XT-THV group (major vascular complication: 2.8% vs 9.9%, P 1: 2.4% vs 9.7%, P < 0.0001). However, the rate of new pacemaker implantation was almost twice as high in the S3-THV group (17.3% vs 9.8%, P = 0.03). In the S3 group, independent predictors of new permanent pacemaker were pre-procedural RBBB (OR = 4.9; P = 0.001), pre-procedural PR duration (OR = 1.14, P = 0.05) and device lack of coaxiality (OR = 1.13; P = 0.05) during deployment. The S3-THV is associated to lower rates of major vascular complications and PVR but higher rates of new pacemaker compared to the XT-THV. Sub-optimal visualization of the S3-THV in relation to the aortic valvular complex during deployment is a predictor of new permanent pacemaker.

  6. Panic Attack or Heart Attack?

    Science.gov (United States)

    ... MPI") that uses a nucleotide tracer (e.g. Thallium) that is injected into your veins to view blood flow to your heart muscle. MPI is used in combination with the stress test to improve accuracy in diagnosing heart disease. Women of child-bearing age may wish to opt for ultrasound ...

  7. Exercise Intolerance in Heart Failure

    DEFF Research Database (Denmark)

    Brassard, Patrice; Gustafsson, Finn

    2016-01-01

    Exercise tolerance is affected in patients with heart failure (HF). Although the inability of the heart to pump blood to the working muscle has been the conventional mechanism proposed to explain the lowered capacity of patients with HF to exercise, evidence suggests that the pathophysiological...

  8. Label-Free LC-MS Profiling of Skeletal Muscle Reveals Heart-Type Fatty Acid Binding Protein as a Candidate Biomarker of Aerobic Capacity.

    Science.gov (United States)

    Malik, Zulezwan Ab; Cobley, James N; Morton, James P; Close, Graeme L; Edwards, Ben J; Koch, Lauren G; Britton, Steven L; Burniston, Jatin G

    2013-12-01

    Two-dimensional gel electrophoresis provides robust comparative analysis of skeletal muscle, but this technique is laborious and limited by its inability to resolve all proteins. In contrast, orthogonal separation by SDS-PAGE and reverse-phase liquid chromatography (RPLC) coupled to mass spectrometry (MS) affords deep mining of the muscle proteome, but differential analysis between samples is challenging due to the greater level of fractionation and the complexities of quantifying proteins based on the abundances of their tryptic peptides. Here we report simple, semi-automated and time efficient ( i.e ., 3 h per sample) proteome profiling of skeletal muscle by 1-dimensional RPLC electrospray ionisation tandem MS. Solei were analysed from rats (n = 5, in each group) bred as either high- or low-capacity runners (HCR and LCR, respectively) that exhibited a 6.4-fold difference (1,625 ± 112 m vs . 252 ± 43 m, p ions, which spanned three orders of magnitude. In total, 207 proteins were analysed, which encompassed almost all enzymes of the major metabolic pathways in skeletal muscle. The most abundant protein detected was type I myosin heavy chain (RA = 5,843 ± 897) and the least abundant protein detected was heat shock 70 kDa protein (RA = 2 ± 0.5). Sixteen proteins were significantly ( p ion (551.21 m/z ) of the doubly-charged peptide SLGVGFATR (454.19 m/z ) of residues 23-31 of FABPH. SRM was conducted on technical replicates of each biological sample and exhibited a coefficient of variation of 20%. The abundance of FABPH measured by SRM was 2.84-fold greater ( p = 0.0095) in HCR muscle. In addition, SRM of FABPH was performed in vastus lateralis samples of young and elderly humans with different habitual activity levels (collected during a previous study) finding FABPH abundance was 2.23-fold greater ( p = 0.0396) in endurance-trained individuals regardless of differences in age. In summary, our findings in HCR/LCR rats provide protein-level confirmation for

  9. Effects of high-intensity interval training on central haemodynamics and skeletal muscle oxygenation during exercise in patients with chronic heart failure

    NARCIS (Netherlands)

    Spee, Ruud F.; Niemeijer, Victor M.; Wijn, Pieter F. F.; Doevendans, Pieter A.; Kemps, Hareld M. C.

    2016-01-01

    Background High-intensity interval training (HIT) improves exercise capacity in patients with chronic heart failure (CHF). Moreover, HIT was associated with improved resting cardiac function. However, the extent to which these improvements actually contribute to training-induced changes in exercise

  10. Influence of shoes and foot orthoses on lower extremity muscle activation onset times in healthy subjects during the transition from double-leg stance to single-leg stance.

    Science.gov (United States)

    Dingenen, B; Peeraer, L; Deschamps, K; Fieuws, S; Janssens, L; Staes, F

    2015-01-01

    The aim of this study was to evaluate the influence of shoes and foot orthoses on lower extremity muscle activation patterns in healthy subjects during the transition from double-leg stance to single-leg stance. Eight male and seven female young asymptomatic adults who wear foot orthoses were recruited. Muscle activation onset times of 9 lower extremity muscles were recorded using surface electromyography during the transition from double-leg stance to single-leg stance, performed with eyes open and with eyes closed. This was tested in 4 experimental conditions: 1) barefoot (BF); 2) shoes only (SO); 3) shoes with standardized FO (SSFO); and 4) shoes with customized FO (SCFO). Based on a four-way (condition-region-leg-vision) linear model for repeated measures, we found a significant condition effect (P=0.025). Differences between conditions did not depend on the leg and/or the vision condition, but on the region (ankle-knee-hip). Based on a two-way (condition-muscle) linear model within each region, only significant differences between conditions for peroneus longus (P=0.003) were found. The onset times of peroneus longus were significantly earlier in SO (P=0.029) and SCFO (P=0.001) compared to BF. These results indicate that SO and SCFO can accelerate peroneus longus muscle activation onset times during the transition from double-leg stance to single-leg stance. Further research is required to determine how these adaptations may develop over time.

  11. Quantitative exercise thallium-201 single photon emission computed tomography for the enhanced diagnosis of ischemic heart disease

    International Nuclear Information System (INIS)

    Mahmarian, J.J.; Boyce, T.M.; Goldberg, R.K.; Cocanougher, M.K.; Roberts, R.; Verani, M.S.

    1990-01-01

    The clinical utility of exercise thallium-201 single photon emission computed tomography was investigated in 360 consecutive patients who had concomitant coronary arteriography. Tomographic images were assessed visually and from computer-quantified polar maps. Sensitivity for detecting coronary artery disease was comparably high using quantitative and visual analysis, although specificity tended to improve using the former method (87% versus 76%, p = 0.09). Quantitative analysis was superior to the visual method for identifying left anterior descending (81% versus 68%, p less than 0.05) and circumflex coronary artery (77% versus 60%, p less than 0.05) stenoses and detected most patients (92%) with multivessel coronary artery disease. Multivessel involvement was correctly predicted in 65% of the patients with more than one critically stenosed vessel. Exercise variables in patients with significant coronary artery disease were similar whether the tomographic images were normal or abnormal. However, patients with coronary stenoses and normal versus abnormal tomograms had a trend toward more single vessel disease (79% versus 62%, p = 0.07) and moderate coronary stenosis (66% versus 28%, p less than 0.001), but had less proximal left anterior descending artery involvement (8% versus 34%, p = 0.05). Computer-quantified perfusion defect size was directly related to the extent of coronary artery disease. Intra- and interobserver agreement for quantifying defects were excellent (r = 0.98 and 0.97, respectively). In conclusion, quantitative thallium-201 tomography offers improved detection of coronary artery disease, localization of the anatomic site of coronary stenosis, prediction of multivessel involvement and accurate determination of perfusion defect size, while maintaining a high specificity

  12. Efficacy and safety of functional electrical stimulation of lower limb muscles in elderly patients with chronic heart failure: A pilot study.

    Science.gov (United States)

    Parissis, John; Karavidas, Apostolos; Farmakis, Dimitrios; Papoutsidakis, Nikolaos; Matzaraki, Vassiliki; Arapi, Sofia; Potamitis, Nikolaos; Nikolaou, Maria; Paraskevaidis, Ioannis; Ikonomidis, Ignatios; Pyrgakis, Vlassios; Kremastinos, Dimitrios; Lekakis, John; Filippatos, Gerasimos

    2015-07-01

    Exercise training is an established modality in chronic heart failure. Functional electrical stimulation (FES) is an effective alternative mode of training in patients unwilling or unable to exercise; however, it has not been investigated in elderly patients. We sought to investigate the effects of FES on functional status, quality of life, emotional status and endothelial function in chronic heart failure patients aged 70 years or higher. Thirty patients with stable systolic chronic heart failure (mean age 75 ± 3 years, New York Heart Association (NYHA) class II/III, 37%/63%) randomly underwent a six-week FES training programme or placebo. Questionnaires addressing quality of life (Kansas City Cardiomyopathy Questionnaire (KCCQ), functional and overall) and emotional stress (Zung self-rating depression scale (SDS), Beck Depression Inventory (BDI)), as well as endothelial function (flow-mediated dilatation) were assessed at baseline and upon protocol completion. A significant improvement in NYHA class (p=0.005), KCCQ-functional (F=68.6, p for interaction<0.001), KCCQ-overall (F=66.9, p<0.001), BDI (F=66.3, p<0.001) and Zung SDS (F=95.1, p<0.001) was observed in the FES group compared to placebo. Patients in the FES group also had a significant increase in flow-mediated dilatation compared with placebo (F=59.1, p<0.01). FES-induced per cent change in flow-mediated dilatation was significantly correlated with respective per cent change in KCCQ functional (r=0.386, p=0.039). In this pilot study, FES effectively improved functional status, quality of life, motional stress and endothelial function in elderly chronic heart failure patients and warrants further investigation in this particular group of patients. © The European Society of Cardiology 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  13. Correlated spectroscopic imaging of calf muscle in three spatial dimensions using group sparse reconstruction of undersampled single and multichannel data.

    Science.gov (United States)

    Wilson, Neil E; Burns, Brian L; Iqbal, Zohaib; Thomas, M Albert

    2015-11-01

    To implement a 5D (three spatial + two spectral) correlated spectroscopic imaging sequence for application to human calf. Nonuniform sampling was applied across the two phase encoded dimensions and the indirect spectral dimension of an echo planar-correlated spectroscopic imaging sequence. Reconstruction was applied that minimized the group sparse mixed ℓ2,1-norm of the data. Multichannel data were compressed using a sensitivity map-based approach with a spatially dependent transform matrix and utilized the self-sparsity of the individual coil images to simplify the reconstruction. Single channel data with 8× and 16× undersampling are shown in the calf of a diabetic patient. A 15-channel scan with 12× undersampling of a healthy volunteer was reconstructed using 5 virtual channels and compared to a fully sampled single slice scan. Group sparse reconstruction faithfully reconstructs the lipid cross peaks much better than ℓ1 minimization. COSY spectra can be acquired over a 3D spatial volume with scan time under 15 min using echo planar readout with highly undersampled data and group sparse reconstruction. © 2015 Wiley Periodicals, Inc.

  14. Muscle Cramps

    Science.gov (United States)

    Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They often occur after ... It is a very common muscle problem. Muscle cramps can be caused by nerves that malfunction. Sometimes ...

  15. Single dose of intra-muscular platelet rich plasma reverses the increase in plasma iron levels in exercise-induced muscle damage: A pilot study

    Directory of Open Access Journals (Sweden)

    Zekine Punduk

    2016-03-01

    Conclusion: Acute exhaustive exercise increased muscle damage markers, including plasma iron, IBC, and ferritin levels, indicating muscle damage induced by exercise. PRP administration improves inflammation by reversing the increase in the iron levels post-exercise without displaying any myotoxicity and may have a role to play in the recovery of exercise-induced muscle damage.

  16. Rbfox-regulated alternative splicing is critical for zebrafish cardiac and skeletal muscle function

    Science.gov (United States)

    Gallagher, Thomas L.; Arribere, Joshua A.; Geurts, Paul A.; Exner, Cameron R. T.; McDonald, Kent L.; Dill, Kariena K.; Marr, Henry L.; Adkar, Shaunak S.; Garnett, Aaron T.; Amacher, Sharon L.; Conboy, John G.

    2012-01-01

    Rbfox RNA binding proteins are implicated as regulators of phylogenetically-conserved alternative splicing events important for muscle function. To investigate the function of rbfox genes, we used morpholino-mediated knockdown of muscle-expressed rbfox1l and rbfox2 in zebrafish embryos. Single and double morphant embryos exhibited changes in splicing of overlapping sets of bioinformatically-predicted rbfox target exons, many of which exhibit a muscle-enriched splicing pattern that is conserved in vertebrates. Thus, conservation of intronic Rbfox binding motifs is a good predictor of Rbfox-regulated alternative splicing. Morphology and development of single morphant embryos was strikingly normal; however, muscle development in double morphants was severely disrupted. Defects in cardiac muscle were marked by reduced heart rate and in skeletal muscle by complete paralysis. The predominance of wavy myofibers and abnormal thick and thin filaments in skeletal muscle revealed that myofibril assembly is defective and disorganized in double morphants. Ultra-structural analysis revealed that although sarcomeres with electron dense M- and Z-bands are present in muscle fibers of rbfox1l/rbox2 morphants, they are substantially reduced in number and alignment. Importantly, splicing changes and morphological defects were rescued by expression of morpholino-resistant rbfox cDNA. Additionally, a target-blocking MO complementary to a single UGCAUG motif adjacent to an rbfox target exon of fxr1 inhibited inclusion in a similar manner to rbfox knockdown, providing evidence that Rbfox regulates the splicing of target exons via direct binding to intronic regulatory motifs. We conclude that Rbfox proteins regulate an alternative splicing program essential for vertebrate heart and skeletal muscle function. PMID:21925157

  17. Rbfox-regulated alternative splicing is critical for zebrafish cardiac and skeletal muscle functions.

    Science.gov (United States)

    Gallagher, Thomas L; Arribere, Joshua A; Geurts, Paul A; Exner, Cameron R T; McDonald, Kent L; Dill, Kariena K; Marr, Henry L; Adkar, Shaunak S; Garnett, Aaron T; Amacher, Sharon L; Conboy, John G

    2011-11-15

    Rbfox RNA binding proteins are implicated as regulators of phylogenetically-conserved alternative splicing events important for muscle function. To investigate the function of rbfox genes, we used morpholino-mediated knockdown of muscle-expressed rbfox1l and rbfox2 in zebrafish embryos. Single and double morphant embryos exhibited changes in splicing of overlapping sets of bioinformatically-predicted rbfox target exons, many of which exhibit a muscle-enriched splicing pattern that is conserved in vertebrates. Thus, conservation of intronic Rbfox binding motifs is a good predictor of Rbfox-regulated alternative splicing. Morphology and development of single morphant embryos were strikingly normal; however, muscle development in double morphants was severely disrupted. Defects in cardiac muscle were marked by reduced heart rate and in skeletal muscle by complete paralysis. The predominance of wavy myofibers and abnormal thick and thin filaments in skeletal muscle revealed that myofibril assembly is defective and disorganized in double morphants. Ultra-structural analysis revealed that although sarcomeres with electron dense M- and Z-bands are present in muscle fibers of rbfox1l/rbox2 morphants, they are substantially reduced in number and alignment. Importantly, splicing changes and morphological defects were rescued by expression of morpholino-resistant rbfox cDNA. Additionally, a target-blocking MO complementary to a single UGCAUG motif adjacent to an rbfox target exon of fxr1 inhibited inclusion in a similar manner to rbfox knockdown, providing evidence that Rbfox regulates the splicing of target exons via direct binding to intronic regulatory motifs. We conclude that Rbfox proteins regulate an alternative splicing program essential for vertebrate heart and skeletal muscle functions. Published by Elsevier Inc.

  18. Being active when you have heart disease

    Science.gov (United States)

    ... regular exercise when you have heart disease is important. Exercise can make your heart muscle stronger. It may ... exercise program. You need to make sure the exercise you would like to do is safe for you. This is especially important if: You recently had a heart attack. You ...

  19. Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength

    Science.gov (United States)

    Paoli, Antonio; Gentil, Paulo; Moro, Tatiana; Marcolin, Giuseppe; Bianco, Antonino

    2017-01-01

    The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ) or multi-joint exercises (MJ) on VO2max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group (n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years) exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc.) and MJ group (n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years) with only MJ exercises (e.g., bench press, squat, etc.). The total work volume (repetitions × sets × load) was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO2max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA) was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO2max (5.1 and 12.5% for SJ and MJ), bench press 1 RM (8.1 and 10.9% for SJ and MJ), knee extension 1 RM (12.4 and 18.9% for SJ and MJ) and squat 1 RM (8.3 and 13.8% for SJ and MJ). In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition. PMID:29312007

  20. Adaptation in properties of skeletal muscle to coronary artery occlusion/reperfusion in rats

    Energy Technology Data Exchange (ETDEWEB)

    Ogoh, Shigehiko [Univ. of North Texas, Fort Worth, TX (United States). Health Science Center; Hirai, Taku [Kyoto Univ. (Japan). Graduate School of Medicine; Nohara, Ryuuji [Kitano Hospital, Osaka (Japan); Taguchi, Sadayoshi [Kyoto Univ. (Japan). Graduate School of Human and Environmental Studies

    2002-10-01

    The present study was designed to determine if changes in function and metabolism of heart muscle induce alterations in characteristics of skeletal muscle. We investigated the histochemical and biochemical properties of soleus (SOL) and extensor digitorum longus (EDL) muscles in Wistar rats at the chronic phase after coronary artery occlusion/reperfusion. The size of myocardial infarct region was evaluated using a high resolution pinhole single photo emission computed tomography (SPECT) system. 4wk after left coronary artery occlusion/reperfusion, the SOL and EDL of hindlimb were dissected out and immersed in isopentane cooled with liquid nitrogen for subsequent histochemical and biochemical analysis. From SPECT imaging, the blood circulation was recovered, but the recovery of fatty acid metabolism was not observed in infarct region of heart. Citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD) activities in infarct region of heart were lower in the myocardial infarction (MI, n=6) group compared with that of age-matched sham-operated (Sham, n=6) group. In addition, heart muscle hypertrophy caused by the dysfunction in MI group was observed. In skeletal muscle, the atrophy and transition of fiber type distribution in MI group, reported in previous studies of heart failure, were not observed. However, the succinate dehydrogenase (SDH) activity in the slow twitch oxidative (SO) from SOL of MI group decreased by 9.8% and in the fast twitch oxidative glycolytic fibers (FOG), 8.0% as compared with sham group. Capillary density of the SO fibers from SOL of MI group also reduced by 18.5% and in the FOG fibers, 18.2% as compared with Sham group. Decreased capillary density in this study related significantly to decreased SDH activity of single muscle fibers in chronic phase of perfusion after surgical infarction. Our results make it clear that there is a difference in the reaction of skeletal muscle to coronary artery occlusion/reperfusion compared with chronic

  1. Adaptation in properties of skeletal muscle to coronary artery occlusion/reperfusion in rats

    International Nuclear Information System (INIS)

    Ogoh, Shigehiko; Taguchi, Sadayoshi

    2002-01-01

    The present study was designed to determine if changes in function and metabolism of heart muscle induce alterations in characteristics of skeletal muscle. We investigated the histochemical and biochemical properties of soleus (SOL) and extensor digitorum longus (EDL) muscles in Wistar rats at the chronic phase after coronary artery occlusion/reperfusion. The size of myocardial infarct region was evaluated using a high resolution pinhole single photo emission computed tomography (SPECT) system. 4wk after left coronary artery occlusion/reperfusion, the SOL and EDL of hindlimb were dissected out and immersed in isopentane cooled with liquid nitrogen for subsequent histochemical and biochemical analysis. From SPECT imaging, the blood circulation was recovered, but the recovery of fatty acid metabolism was not observed in infarct region of heart. Citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD) activities in infarct region of heart were lower in the myocardial infarction (MI, n=6) group compared with that of age-matched sham-operated (Sham, n=6) group. In addition, heart muscle hypertrophy caused by the dysfunction in MI group was observed. In skeletal muscle, the atrophy and transition of fiber type distribution in MI group, reported in previous studies of heart failure, were not observed. However, the succinate dehydrogenase (SDH) activity in the slow twitch oxidative (SO) from SOL of MI group decreased by 9.8% and in the fast twitch oxidative glycolytic fibers (FOG), 8.0% as compared with sham group. Capillary density of the SO fibers from SOL of MI group also reduced by 18.5% and in the FOG fibers, 18.2% as compared with Sham group. Decreased capillary density in this study related significantly to decreased SDH activity of single muscle fibers in chronic phase of perfusion after surgical infarction. Our results make it clear that there is a difference in the reaction of skeletal muscle to coronary artery occlusion/reperfusion compared with chronic

  2. Ex vivo gene editing of the dystrophin gene in muscle stem cells mediated by peptide nucleic acid single stranded oligodeoxynucleotides induces stable expression of dystrophin in a mouse model for Duchenne muscular dystrophy.

    Science.gov (United States)

    Nik-Ahd, Farnoosh; Bertoni, Carmen

    2014-07-01

    Duchenne muscular dystrophy (DMD) is a fatal disease caused by mutations in the dystrophin gene, which result in the complete absence of dystrophin protein throughout the body. Gene correction strategies hold promise to treating DMD. Our laboratory has previously demonstrated the ability of peptide nucleic acid single-stranded oligodeoxynucleotides (PNA-ssODNs) to permanently correct single-point mutations at the genomic level. In this study, we show that PNA-ssODNs can target and correct muscle satellite cells (SCs), a population of stem cells capable of self-renewing and differentiating into muscle fibers. When transplanted into skeletal muscles, SCs transfected with correcting PNA-ssODNs were able to engraft and to restore dystrophin expression. The number of dystrophin-positive fibers was shown to significantly increase over time. Expression was confirmed to be the result of the activation of a subpopulation of SCs that had undergone repair as demonstrated by immunofluorescence analyses of engrafted muscles using antibodies specific to full-length dystrophin transcripts and by genomic DNA analysis of dystrophin-positive fibers. Furthermore, the increase in dystrophin expression detected over time resulted in a significant improvement in muscle morphology. The ability of transplanted cells to return into quiescence and to activate upon demand was confirmed in all engrafted muscles following injury. These results demonstrate the feasibility of using gene editing strategies to target and correct SCs and further establish the therapeutic potential of this approach to permanently restore dystrophin expression into muscle of DMD patients. © 2014 AlphaMed Press.

  3. Haemodynamic consequences of targeted single- and dual-site right ventricular pacing in adults with congenital heart disease undergoing surgical pulmonary valve replacement

    Science.gov (United States)

    Plymen, Carla M.; Finlay, Malcolm; Tsang, Victor; O'leary, Justin; Picaut, Nathalie; Cullen, Shay; Walker, Fiona; Deanfield, John E; Hsia, T.Y.; Bolger, Aidan P.; Lambiase, Pier D.

    2015-01-01

    Aims The purpose of this study was to create an epicardial electroanatomic map of the right ventricle (RV) and then apply post-operative-targeted single- and dual-site RV temporary pacing with measurement of haemodynamic parameters. Cardiac resynchronization therapy is an established treatment for symptomatic left ventricular (LV) dysfunction. In congenital heart disease, RV dysfunction is a common cause of morbidity—little is known regarding the potential benefits of CRT in this setting. Methods and results Sixteen adults (age = 32 ± 8 years; 6 M, 10 F) with right bundle branch block (RBBB) and repaired tetralogy of Fallot (n = 8) or corrected congenital pulmonary stenosis (n = 8) undergoing surgical pulmonary valve replacement (PVR) for pulmonary regurgitation underwent epicardial RV mapping and haemodynamic assessment of random pacing configurations including the site of latest RV activation. The pre-operative pulmonary regurgitant fraction was 49 ± 10%; mean LV end-diastolic volume (EDV) 85 ± 19 mL/min/m2 and RVEDV 183 ± 89 mL/min/m2 on cardiac magnetic resonance imaging. The mean pre-operative QRS duration is 136 ± 26 ms. The commonest site of latest activation was the RV free wall and DDD pacing here alone or combined with RV apical pacing resulted in significant increases in cardiac output (CO) vs. AAI pacing (P < 0.01 all measures). DDDRV alternative site pacing significantly improved CO by 16% vs. AAI (P = 0.018), and 8.5% vs. DDDRV apical pacing (P = 0.02). Conclusion Single-site RV pacing targeted to the region of latest activation in patients with RBBB undergoing PVR induces acute improvements in haemodynamics and supports the concept of ‘RV CRT’. Targeted pacing in such patients has therapeutic potential both post-operatively and in the long term. PMID:25371427

  4. Effect of single intraoperative dose of amiodarone in patients with rheumatic valvular heart disease and atrial fibrillation undergoing valve replacement surgery

    Directory of Open Access Journals (Sweden)

    Selvaraj Thiruvenkadam

    2009-01-01

    Full Text Available Maintenance of sinus rhythm (SR is superior to rate control in atrial fibrillation (AF. In order to achieve SR, we administered single-dose intravenous amiodarone intraoperatively and evaluated its effect on conversion of rheumatic AF to SR in patients undergoing valvular heart surgery. Patients were randomly assigned to amiodarone ( n = 42 or control ( n = 40 group in a double blind manner. The amiodarone group received amiodarone (3 mg/kg intravenously prior to the institution of cardiopulmonary bypass and the control group received the same volume of normal saline. In the amiodarone group, the initial rhythm after the release of aortic cross clamp was noted to be AF in 14.3% ( n = 6 and remained so in 9.5% ( n = 4 of patients till the end of surgery. In the control group, the rhythm soon after the release of aortic cross clamp was AF in 37.5% ( n = 15 ( p = 0.035 and remained so in 32.5% ( n = 13 of patients till the end of surgery ( p = 0.01. At the end of first post-operative day 21.4% ( n = 9 of patients in amiodarone group and 55% ( n = 22 of patients in control group were in AF ( p = 0.002. The requirement of cardioversion/defibrillation was 1.5 (±0.54 in amiodarone group and 2.26 (±0.73 in the control group ( p = 0.014, and the energy needed was 22.5 (±8.86 joules in the amiodarone group and 40.53 (±16.5 in the control group ( p = 0.008. A single intraoperative dose of intravenous amiodarone increased the conversion rate of AF to normal sinus rhythm, reduced the need and energy required for cardioversion/defibrillation and reduced the recurrence of AF within one day.

  5. Rapid radiotracer washout from the heart: effect on image quality in SPECT performed with a single-headed gamma camera system.

    Science.gov (United States)

    O'Connor, M K; Cho, D S

    1992-06-01

    Technetium-99m-teboroxime demonstrates high extraction and rapid washout from the myocardium. To evaluate the feasibility of performing SPECT with this agent using a single-headed gamma camera system, a series of phantom studies were performed that simulated varying degrees of washout from normal and "ischemic" regions of the myocardium. In the absence of ischemic regions, short axis profiles were relatively unaffected by washout of less than 50% of activity over the duration of a SPECT acquisition. However, significant corruption of the SPECT data was observed when large (greater than a factor of 2) differences existed in the washout of activity from normal and "ischemic" myocardium. This corruption was observed with 30%-40% washout of activity from normal regions of the heart. Based on published washout rates, these results indicate that clinical studies with 99mTc-teboroxime may need to be completed within 2-4 min to order to prevent degradation of image quality due to differential washout effects.

  6. Do neonatal mouse hearts regenerate following heart apex resection?

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Ganesalingam, Suganya; Jensen, Charlotte Harken

    2014-01-01

    strains and found no evidence of complete regeneration. Ideally, new functional cardiomyocytes, endothelial cells, and vascular smooth muscle cells should be formed in the necrotic area of the damaged heart. Here, damaged hearts were 9.8% shorter and weighed 14% less than sham controls. In addition......, the resection border contained a massive fibrotic scar mainly composed of nonmyocytes and collagen disposition. Furthermore, there was a substantial reduction in the number of proliferating cardiomyocytes in AR hearts. Our results thus question the usefulness of the AR model for identifying molecular mechanisms...... underlying regeneration of the adult heart after damage....

  7. 18F-fluorodeoxyglucose accumulation in the heart, brain and skeletal muscle of rats; the influence of time after injection, depressed lipid metabolism and glucose-insulin

    International Nuclear Information System (INIS)

    Kasalicky, J.; Konopkova, M.; Melichar, F.

    2001-01-01

    To study the effect of lipid depressing drugs on 18 FDG myocardial concentration. The changes of 18 FDG uptake in myocardium, brain and skeletal muscle of rats were compared as influenced by acipimox, tyloxapol and glucose with insulin. 5.55 MBq of 18 FDG were administered to Wistar rats. Control rats were killed 15, 30, 45 and 60 minutes following intravenous injection and the radioactivity concentration (cpm/g of tissue) in relation to injected cpm was determined in a well crystal adjusted to 511 KeV in order to check the time of maximal 18 FDG tissue uptake. The radioactivity in myocardium, skeletal muscle and brain in intact animals was compared with that of rats treated with tyloxapol (tritton WR 1339, 125 mg intravenously immediately before 18 FDG injection), acipimox (nicotinic acid derivative, 25 mg by stomach cannula 15 minutes before 18 FDG), or glucose with insulin (intravenous injection of 0.04 g and 0.04 UI immediately before 18 FDG). The animals were killed 45 minutes following 18 FDG injection. Tyloxapol and acipimox significantly elevated myocardial 18 FDG concentration (tyloxapol +37% and acipimox +48%), but the increase in 18 FDG concentration after glucose and insulin was slight and insignificant. The changes in skeletal muscle after lipid depressing agents were quite contrasting; the decrease in 18 FDG concentration was -74% after tyloxapol and -44% following acipimox administration. The accumulation of 18 FDG in brain was not influenced markedly by the drugs used or by glucose with insulin. The highest 18 FDG uptake in myocardium could be achieved by depressing the lipid metabolism and not by administration of glucose with insulin only. A marked increase in glucose accumulation in myocardium is not possible without previous shift from the utilisation of fatty acids. This finding is fully in agreement with present knowledge about energetic metabolism of myocardium. (author)

  8. Heart Failure

    Science.gov (United States)

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  9. Angiogenesis in hepatocellular carcinoma: correlation of single-level dynamic spiral CT scans in arterial phase and expression of α-smooth muscle actin

    International Nuclear Information System (INIS)

    Liu Yan; Min Pengqiu; Chen Weixia; Zhang Lin

    2005-01-01

    Objective: To investigate the correlation between the single-level dynamic spiral CT scans (SDCT) of hepatocellular carcinoma (HCC) in arterial phase (AP) and the immunohistochemistry expression of α-smooth muscle actin (ASMA). Methods: 33 cases of suspected HCC undergoing spiral CT plain scan of the whole liver, the single-level dynamic scan of the target level of lesion in AP and finally the whole liver scan in portal-venous phase before operations and proved after were included into the study. After the SDCT, a time-density curve (T-DC) was drawn according to the density change of the region of interest (ROI) of the tumor parenchyma with some parameters calculated, and signs of enhancement evaluated. Slices of post-operation specimen underwent hemotoxylin-eosin (HE) and ASMA immunohistochemistry staining. Then the slices were evaluated with emphases on the ASMA-positive neovasculatures in the parenchyma and mesenchyma of carcinomas, and the average count in a low microscopic field (x 100) was recorded (5 low microscopic field were observed and then an average was calculated.). Finally the immunohistochemistry and histologic results were correlated with image findings. Results: According to the PV of the tumor parenchyma, T-DC was divided into type I, II and III in which the criteria were PV>80, 40 HU< PV< 80 HU and PV<40 HU respectively. In the 33 cases, type I, II and III of T-DC were 3, 17 and 13 cases with PV of 103.30, 57.65 and 33.55 HU respectively. In ASMA immunohistochemistry study, ASMA-positive neovasculatures were devided into type A with a thick wall and B with a thin wall. The mean count of neovasculatures of tumor parenchyma in type I, II and III of T-DC were 10, 4.59 and 1 respectively. Statistically, different types of T-DC were significantly correlated with the count of neovasculatures in the parenchyma of carcinomas (r=-0.567, P<0.01). Homogeneous and inhomogeneous enhancement of carcinomas during SDCT in AP were correlated with the

  10. The Acute Effects of Unilateral Ankle Plantar Flexors Static- Stretching on Postural Sway and Gastrocnemius Muscle Activity During Single-Leg Balance Tasks

    Directory of Open Access Journals (Sweden)

    Bráulio N. Lima, Paulo R.G. Lucareli, Willy A. Gomes, Josinaldo J. Silva, Andre S. Bley, Erin H. Hartigan, Paulo H. Marchetti

    2014-09-01

    Full Text Available The aim of this study was to investigate the acute effects of unilateral ankle plantar flexors static- stretching on surface electromyography (sEMG and the center of pressure (COP during a single-leg balance task in both lower limbs. Fourteen young healthy, non-athletic individuals performed unipodal quiet standing for 30s before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch a unilateral ankle plantar flexor static- stretching protocol [6 sets of 45s/15s, 70-90% point of discomfort (POD]. Postural sway was described using the COP area, COP speed (antero-posterior and medio-lateral directions and COP frequency (antero-posterior and medio-lateral directions. Surface EMG (EMG integral [IEMG] and Median frequency[FM] was used to describe the muscular activity of gastrocnemius lateralis. Ankle dorsiflexion passive range of motion increased in the stretched limb before and after the static-stretching protocol (mean ± SD: 15.0° ± 6.0 and 21.5° ± 7.0 [p < 0.001]. COP area and IEMG increased in the stretch limb between pre-stretching and immediately post-stretching (p = 0.015 and p = 0.036, respectively. In conclusion, our static- stretching protocol effectively increased passive ankle ROM. The increased ROM appears to increase postural sway and muscle activity; however these finding were only a temporary or transient effect.

  11. Long-term safety and stability of angiogenesis induced by balanced single-vector co-expression of PDGF-BB and VEGF164 in skeletal muscle

    Science.gov (United States)

    Gianni-Barrera, Roberto; Burger, Maximilian; Wolff, Thomas; Heberer, Michael; Schaefer, Dirk J.; Gürke, Lorenz; Mujagic, Edin; Banfi, Andrea

    2016-01-01

    Therapeutic angiogenesis by growth factor delivery is an attractive treatment strategy for ischemic diseases, yet clinical efficacy has been elusive. The angiogenic master regulator VEGF-A can induce aberrant angiogenesis if expressed above a threshold level. Since VEGF remains localized in the matrix around expressing cells, homogeneous dose distribution in target tissues is required, which is challenging. We found that co-expression of the pericyte-recruiting factor PDGF-BB at a fixed ratio with VEGF from a single bicistronic vector ensured normal angiogenesis despite heterogeneous high VEGF levels. Taking advantage of a highly controlled gene delivery platform, based on monoclonal populations of transduced myoblasts, in which every cell stably produces the same amount of each factor, here we rigorously investigated a) the dose-dependent effects, and b) the long-term safety and stability of VEGF and PDGF-BB co-expression in skeletal muscle. PDGF-BB co-expression did not affect the normal angiogenesis by low and medium VEGF doses, but specifically prevented vascular tumors by high VEGF, yielding instead normal and mature capillary networks, accompanied by robust arteriole formation. Induced angiogenesis persisted unchanged up to 4 months, while no tumors appeared. Therefore, PDGF-BB co-expression is an attractive strategy to improve safety and efficacy of therapeutic angiogenesis by VEGF gene delivery. PMID:26882992

  12. A Single CRISPR-Cas9 Deletion Strategy that Targets the Majority of DMD Patients Restores Dystrophin Function in hiPSC-Derived Muscle Cells.

    Science.gov (United States)

    Young, Courtney S; Hicks, Michael R; Ermolova, Natalia V; Nakano, Haruko; Jan, Majib; Younesi, Shahab; Karumbayaram, Saravanan; Kumagai-Cresse, Chino; Wang, Derek; Zack, Jerome A; Kohn, Donald B; Nakano, Atsushi; Nelson, Stanley F; Miceli, M Carrie; Spencer, Melissa J; Pyle, April D

    2016-04-07

    Mutations in DMD disrupt the reading frame, prevent dystrophin translation, and cause Duchenne muscular dystrophy (DMD). Here we describe a CRISPR/Cas9 platform applicable to 60% of DMD patient mutations. We applied the platform to DMD-derived hiPSCs where successful deletion and non-homologous end joining of up to 725 kb reframed the DMD gene. This is the largest CRISPR/Cas9-mediated deletion shown to date in DMD. Use of hiPSCs allowed evaluation of dystrophin in disease-relevant cell types. Cardiomyocytes and skeletal muscle myotubes derived from reframed hiPSC clonal lines had restored dystrophin protein. The internally deleted dystrophin was functional as demonstrated by improved membrane integrity and restoration of the dystrophin glycoprotein complex in vitro and in vivo. Furthermore, miR31 was reduced upon reframing, similar to observations in Becker muscular dystrophy. This work demonstrates the feasibility of using a single CRISPR pair to correct the reading frame for the majority of DMD patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Heart Anatomy

    Science.gov (United States)

    ... kilometers), which is far enough to circle the earth more than twice! See also on other sites: ... For the Public Heart Information Center Project Heart Women’s Heart Health Clinical Trials 6770 Bertner Avenue Houston, ...

  14. Know the Warning Signs of a Heart Attack

    Science.gov (United States)

    ... No. 22 Know the Warning Signs of a Heart Attack What is a heart attack? Aheart attack happens when the blood vessels that ... hurting your heart muscle. Another name for a heart attack is myocardial infarction, or MI. If you have ...

  15. Pulse pressure as a haemodynamic variable in systolic heart failure

    NARCIS (Netherlands)

    Petrie, Colin James

    2016-01-01

    In patients with heart failure, the heart is unable to pump enough blood to satisfy the requirements of the body. Explanations for this include heart muscle damage after a heart attack. This could be very recently, or in the past, sometimes dating back many years. In other cases the explanation for

  16. Aging changes in the heart and blood vessels

    Science.gov (United States)

    ... vessels URL of this page: //medlineplus.gov/ency/article/004006.htm Aging changes in the heart and blood vessels To ... changes in the heart include deposits of the "aging pigment," lipofuscin . The heart muscle cells degenerate slightly. The valves inside the heart, which ...

  17. Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength

    Directory of Open Access Journals (Sweden)

    Antonio Paoli

    2017-12-01

    Full Text Available The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ or multi-joint exercises (MJ on VO2max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group (n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc. and MJ group (n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years with only MJ exercises (e.g., bench press, squat, etc.. The total work volume (repetitions × sets × load was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO2max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO2max (5.1 and 12.5% for SJ and MJ, bench press 1 RM (8.1 and 10.9% for SJ and MJ, knee extension 1 RM (12.4 and 18.9% for SJ and MJ and squat 1 RM (8.3 and 13.8% for SJ and MJ. In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition.

  18. Effects of calcium, inorganic phosphate, and pH on isometric force in single skinned cardiomyocytes from donor and failing human hearts

    NARCIS (Netherlands)

    van der Velden, J.; Klein, L. J.; Zaremba, R.; Boontje, N. M.; Huybregts, M. A.; Stooker, W.; Eijsman, L.; de Jong, J. W.; Visser, C. A.; Visser, F. C.; Stienen, G. J.

    2001-01-01

    During ischemia, the intracellular calcium and inorganic phosphate (P(i)) concentrations rise and pH falls. We investigated the effects of these changes on force development in donor and failing human hearts to determine if altered contractile protein composition during heart failure changes the

  19. Quantitative assessment of muscle in dogs using a vertebral epaxial muscle score.

    Science.gov (United States)

    Freeman, Lisa M; Sutherland-Smith, James; Prantil, Lori R; Sato, Amy F; Rush, John E; Barton, Bruce A

    2017-10-01

    Muscle loss associated with disease (cachexia) or with aging (sarcopenia) is common in dogs, but clinically relevant methods for quantifying muscle loss are needed. We previously validated an ultrasound method of quantifying muscle size in dogs in a single breed. The goal of this study was to assess the variability and reproducibility of the Vertebral Epaxial Muscle Score (VEMS) in other dog breeds. Static ultrasound images were obtained from 38 healthy, neutered dogs of 5 different breeds between 1- and 5-years-old. The maximal transverse right epaxial muscle height and area at the level of the 13th thoracic vertebra (T13) were measured. Length of the 4th thoracic vertebra (T4) was measured from thoracic radiography. Ratios of the muscle height and area to vertebral length (height/T4 and area/T4, respectively) were calculated to account for differences in body size among breeds. Reproducibility testing was performed on 2 dogs of each breed (26% of the total) to determine intra- and inter-investigator reproducibility, as well as intra-class correlation. Mean height/T4 = 1.02 ± 0.18 and mean area/T4 = 3.32 ± 1.68. There was no significant difference for height/T4 ( P = 0.10) among breeds, but breeds were significantly different in area/T4 ( P dogs of different sizes and body conformations. Studies assessing this technique in dogs with congestive heart failure and other diseases associated with muscle loss are warranted.

  20. Radiochemicals used to scan the heart

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Techniques for heart scanning using 201 Tl and /sup 99m/Tc pyrophosphate are discussed. Thallium-201, produced artificially in a cyclotron, concentrates in normal heart muscle but not in abnormal tissue. Technetium-99m is deposited in mitochondria of heart cells that are irreversibly damaged. The combined use of 201 Tl and /sup 99m/Tc makes it possible to identify regions of recent heart damage as well as older heart damage. Advantages of using 129 Cs for heart scanning are also discussed

  1. Muscle Deoxygenation Causes Muscle Fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D.

    1999-01-01

    Muscle fatigue is a common musculoskeletal disorder in the work place, and may be a harbinger for more disabling cumulative trauma disorders. Although the cause of fatigue is multifactorial, reduced blood flow and muscle oxygenation may be the primary factor in causing muscle fatigue during low intensity muscle exertion. Muscle fatigue is defined as a reduction in muscle force production, and also occurs among astronauts who are subjected to postural constraints while performing lengthy, repetitive tasks. The objectives of this research are to: 1) develop an objective tool to study the role of decreased muscle oxygenation on muscle force production, and 2) to evaluate muscle fatigue during prolonged glovebox work.

  2. A single intracoronary injection of midkine reduces ischemia/reperfusion injury in swine hearts: a novel therapeutic approach for acute coronary syndrome

    Directory of Open Access Journals (Sweden)

    Hisaaki eIshiguro

    2011-06-01

    Full Text Available Several growth factors are effective for salvaging myocardium and limiting infarct size in experimental studies with small animals. Their benefit in large animals and feasibility in clinical practice remains to be elucidated. We investigate the cardioprotective effect of midkine (MK in swine subjected to ischemia/reperfusion (I/R. I/R was created in swine by left anterior descending coronary artery occlusion for 45 min using a percutaneous over-the-wire balloon catheter. MK protein was injected as a bolus through the catheter at the initiation of reperfusion (midkine injected group; MKT. Saline was injected in controls (CONT. Survival rate 24h after I/R was significantly higher in MKT than in CONT, whereas infarct size/area at risk was almost 5 times smaller. Echocardiography in MKT revealed a significantly higher percent wall thickening of the interventricular septum, a higher % fractional shortening and a lower E/e’ compared with CONT. LV catheterization in MKT showed a lower LVEDP, and a higher dP/dtmax compared with CONT. TUNEL-positive myocytes and CD45-positive cell infiltration in the peri-infarct area were significantly less in MKT than in CONT. Here, we showed that a single intracoronary injection of MK protein in swine hearts at the onset of reperfusion dramatically reduces infarct size and mortality and ameliorates systolic/diastolic LV function. This beneficial effect is associated with a reduction of apoptotic and inflammatory reactions. MK application during percutaneous coronary intervention may become a promising adjunctive therapy in acute coronary syndromes.

  3. A Single Nucleotide Polymorphism in the Stromal Cell-Derived Factor 1 Gene Is Associated with Coronary Heart Disease in Chinese Patients

    Directory of Open Access Journals (Sweden)

    Lei Feng

    2014-06-01

    Full Text Available Coronary heart disease (CHD is highly prevalent globally and a major cause of mortality. Genetic predisposition is a non-modifiable risk factor associated with CHD. Eighty-four Chinese patients with CHD and 253 healthy Chinese controls without CHD were recruited. Major clinical data were collected, and a single nucleotide polymorphism (SNP in the stromal cell-derived factor 1 (SDF-1 gene at position 801 (G to A, rs1801157 in the 3'-untranslated region was identified. The correlation between rs1801157 genotypes and CHD was evaluated by a multivariate logistic regression analysis. The allele frequency in the CHD and control groups was in Hardy-Weinberg equilibrium (HWE (p > 0.05. The frequency of the GG genotype in the CHD group (59.5% was significantly higher than that in the control group (49.8% (p = 0.036. A number of variables, including male sex, age, presence of hypertension, and the levels of low-density lipoprotein cholesterol (LDL-C, high-density lipoprotein cholesterol (HDL-C, triglycerides (TG, uric acid, and total bilirubin, were associated with CHD in a primary univariate analysis. In a multivariable logistic regression analysis, the GG genotype (GG:AA, odds ratio (OR = 2.31, 95% confidence interval (CI = 1.21–5.23, male sex, advanced age (≥60 years, presence of hypertension, LDL-C level ≥ 3.33 mg/dL, HDL-C level < 1.03 mg/dL, and TG level ≥ 1.7 mg/dL were independent risk factors for CHD.

  4. A single-dose, open-label, parallel, randomized, dose-proportionality study of paliperidone after intramuscular injections of paliperidone palmitate in the deltoid or gluteal muscle in patients with schizophrenia.

    Science.gov (United States)

    Cleton, Adriaan; Rossenu, Stefaan; Crauwels, Herta; Berwaerts, Joris; Hough, David; Gopal, Srihari; Eerdekens, Marielle; Vandebosch, An; Remmerie, Bart; De Meulder, Marc; Rosso, Clara M

    2014-09-01

    Paliperidone palmitate (PP) is a long-acting injectable (LAI) antipsychotic, developed for monthly intramuscular (i.m.) administration into deltoid/gluteal muscle, approved for the treatment of schizophrenia in many countries. To assess the options for i.m. injection sites, dose-proportionality of PP was investigated after injection of a single dose (25-150 mg eq.) of PP in either gluteal (n = 106) or deltoid (n = 95) muscle of schizophrenic patients. Overall, mean (geometric) area under plasma concentration-time curve from time zero to infinity (AUC∞ ) of paliperidone increased proportionally with increasing PP doses, regardless of injection site. Mean maximum plasma concentration (Cmax ) was slightly less than dose-proportional for both injection sites at PP doses >50 mg eq. Mean Cmax was higher after injection in the deltoid compared with the gluteal muscle, except for the 100 mg eq. dose, while AUC∞ for both injection sites was comparable at all doses. Median time to reach Cmax (tmax ) ranged from 13-14 days after deltoid and 13-17 days after gluteal injection across all doses. Single PP injections in deltoid and gluteal muscles in the dose range of 25-150 mg eq. were generally tolerable both locally and systemically. © 2014, The American College of Clinical Pharmacology.

  5. Heart Attack

    Science.gov (United States)

    Each year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly ... it's important to know the symptoms of a heart attack and call 9-1-1 if you or ...

  6. Heart Transplantation

    Science.gov (United States)

    A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the last resort for people with heart failure when all other treatments have failed. The ...

  7. Heart Diseases

    Science.gov (United States)

    ... re like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. ... disability. There are many different forms of heart disease. The most common cause of heart disease is ...

  8. A single-center retrospective clinicopathologic study of endomyocardial biopsies after heart transplant at Baskent University Hospital in Ankara, 1993-2014.

    Science.gov (United States)

    Terzi, Ayşen; Sezgin, Atilla; Tunca, Zeynep; Deniz, Ebru; Ayva, Ebru Şebnem; Haberal Reyhan, Nihan; Müderrisoğlu, Haldun; Özdemir, Binnaz Handan

    2015-04-01

    The purpose of this study was to investigate the frequency and prognostic importance of acute cellular rejection after heart transplant. All 84 heart transplant patients at our center from January 1993 to January 2014, including all 576 endomyocardial biopsies, were evaluated with retrospective review of clinical records and endomyocardial biopsies. Routine and clinically indicated endomyocardial biopsies after heart transplant were graded for acute cellular rejection (2005 International Society for Heart and Lung Transplantation Working Formulation). Survival analysis was performed using Kaplan-Meier method. There were 61 male (73%) and 23 female recipients. Median age at heart transplant was 29 years (range, 1-62 y). Posttransplant early mortality rate was 17.9% (15 patients). In the other 69 patients, 23 patients died and 46 patients (66.7%) were alive at mean 69.3 ± 7.2 months after heart transplant. Mean follow-up was 35.4 ± 29.8 months (range, 0.07-117.5 mo). Mean 8.4 ± 4.2 endomyocardial biopsies (range, 1-19 biopsies) were performed per patient. Median first biopsy time was 7 days (range, 1-78 d). The frequency of posttransplant acute cellular rejection was 63.8% (44 of 69 patients) by histopathology; 86% patients experienced the first episode of acute cellular rejection within 6 months after transplant. There were 18 patients with acute cellular rejection ≥ grade 2R on ≥ 1 endomyocardial biopsy in 44 patients with acute cellular rejection. No significant difference was observed between survival rates of patients with grade 1R or ≥ grade 2R acute cellular rejection, or between survival rates of patients with or without diagnosis of any grade of acute cellular rejection. Acute cellular rejection was not related to any prognostic risk factor. Acute cellular rejection had no negative effect on heart recipient long-term survival, but it was a frequent complication after heart transplant, especially within the first 6 months.

  9. Combined heart-kidney transplantation after total artificial heart insertion.

    Science.gov (United States)

    Ruzza, A; Czer, L S C; Ihnken, K A; Sasevich, M; Trento, A; Ramzy, D; Esmailian, F; Moriguchi, J; Kobashigawa, J; Arabia, F

    2015-01-01

    We present the first single-center report of 2 consecutive cases of combined heart and kidney transplantation after insertion of a total artificial heart (TAH). Both patients had advanced heart failure and developed dialysis-dependent renal failure after implantation of the TAH. The 2 patients underwent successful heart and kidney transplantation, with restoration of normal heart and kidney function. On the basis of this limited experience, we consider TAH a safe and feasible option for bridging carefully selected patients with heart and kidney failure to combined heart and kidney transplantation. Recent FDA approval of the Freedom driver may allow outpatient management at substantial cost savings. The TAH, by virtue of its capability of providing pulsatile flow at 6 to 10 L/min, may be the mechanical circulatory support device most likely to recover patients with marginal renal function and advanced heart failure. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Volumetric Single-Beat Coronary Computed Tomography Angiography: Relationship of Image Quality, Heart Rate, and Body Mass Index. Initial Patient Experience With a New Computed Tomography Scanner.

    Science.gov (United States)

    Latif, Muhammad Aamir; Sanchez, Frank W; Sayegh, Karl; Veledar, Emir; Aziz, Muhammad; Malik, Rehan; Haider, Imran; Agatston, Arthur S; Batlle, Juan C; Janowitz, Warren; Peña, Constantino; Ziffer, Jack A; Nasir, Khurram; Cury, Ricardo C

    2016-01-01

    Cardiac computed tomography (CT) image quality (IQ) is very important for accurate diagnosis. We propose to evaluate IQ expressed as Likert scale, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) from coronary CT angiography images acquired with a new volumetric single-beat CT scanner on consecutive patients and assess the IQ dependence on heart rate (HR) and body mass index (BMI). We retrospectively analyzed the data of the first 439 consecutive patients (mean age, 55.13 [SD, 12.1] years; 51.47% male), who underwent noninvasive coronary CT angiography in a new single-beat volumetric CT scanner (Revolution CT) to evaluate chest pain at West Kendall Baptist Hospital. Based on patient BMI (mean, 29.43 [SD, 5.81] kg/m), the kVp (kilovolt potential) value and tube current were adjusted within a range of 80 to 140 kVp and 122 to 720 mA, respectively. Each scan was performed in a single-beat acquisition within 1 cardiac cycle, regardless of the HR. Motion correction software (SnapShot Freeze) was used for correcting motion artifacts in patients with higher HRs. Autogating was used to automatically acquire systolic and diastolic phases for higher HRs with electrocardiographic milliampere dose modulation. Image quality was assessed qualitatively by Likert scale and quantitatively by SNR and CNR for the 4 major vessels right coronary, left main, left anterior descending, and left circumflex arteries on axial and multiplanar reformatted images. Values for Likert scale were as follows: 1, nondiagnostic; 2, poor; 3, good; 4, very good; and 5, excellent. Signal-to-noise ratio and CNR were calculated from the average 2 CT attenuation values within regions of interest placed in the proximal left main and proximal right coronary artery. For contrast comparison, a region of interest was selected from left ventricular wall at midcavity level using a dedicated workstation. We divided patients in 2 groups related to the HR: less than or equal to 70 beats/min (bpm) and

  11. Muscle pain

    African Journals Online (AJOL)

    Key Summary Points. • Muscle pain, known as myalgia, can be in one targeted area or across many muscles, occurring with overexertion or overuse of these muscles. • Pain can be classified as acute or chronic pain and further categorized as nociceptive or neuropathic. • Causes of muscle pain include stress, physical ...

  12. Enhanced skeletal muscle ribosome biogenesis, yet attenuated mTORC1 and ribosome biogenesis-related signalling, following short-term concurrent versus single-mode resistance training

    OpenAIRE

    Fyfe, Jackson J.; Bishop, David J.; Bartlett, Jonathan D.; Hanson, Erik D.; Anderson, Mitchell J.; Garnham, Andrew P.; Stepto, Nigel K.

    2018-01-01

    Combining endurance training with resistance training (RT) may attenuate skeletal muscle hypertrophic adaptation versus RT alone; however, the underlying mechanisms are unclear. We investigated changes in markers of ribosome biogenesis, a process linked with skeletal muscle hypertrophy, following concurrent training versus RT alone. Twenty-three males underwent eight weeks of RT, either performed alone (RT group, n = 8), or combined with either high-intensity interval training (HIT+RT group, ...

  13. Single molecular image of cytosolic free Ca2+ of skeletal muscle cells in rats pre- and post-exercise-induced fatigue

    Science.gov (United States)

    Liu, Yi; Zhang, Heming; Zhao, Yanping; Liu, Zhiming

    2009-08-01

    A growing body of literature indicated the cytosolic free Ca2+ concentration of skeletal muscle cells changes significantly during exercise-induced fatigue. But it is confusing whether cytosolic free Ca2+ concentration increase or decrease. Furthermore, current researches mainly adopt muscle tissue homogenate as experiment material, but the studies based on cellular and subcellular level is seldom. This study is aimed to establish rat skeletal muscle cell model of exercise-induced fatigue, and confirm the change of cytosolic free Ca2+ concentration of skeletal muscle cells in rats preand post- exercise-induced fatigue. In this research, six male Wistar rats were randomly divided into two groups: control group (n=3) and exercise-induced fatigue group (n=3). The former group were allowed to freely move and the latter were forced to loaded swimming to exhaustive. Three days later, all the rats were sacrificed, the muscle tissue from the same site of skeletal muscle were taken out and digested to cells. After primary culture of the two kinds of skeletal muscle cells from tissue, a fluorescent dye-Fluo-3 AM was used to label the cytosolic free Ca2+. The fluorescent of Ca2+ was recorded by confocal laser scanning microscopy. The results indicated that, the Ca2+ fluorescence intensity of cells from the rat of exercise-induced fatigue group was significantly higher than those in control group. In conclusion, cytosolic free Ca2+ concentration of skeletal muscle cells has a close relation with exercise-induced fatigue, and the increase of cytosolic free Ca2+ concentration may be one of the important factors of exercise-induced fatigue.

  14. Striated Muscle Function, Regeneration, and Repair

    Science.gov (United States)

    Shadrin, I.Y.; Khodabukus, A.; Bursac, N.

    2016-01-01

    As the only striated muscle tissues in the body, skeletal and cardiac muscle share numerous structural and functional characteristics, while exhibiting vastly different size and regenerative potential. Healthy skeletal muscle harbors a robust regenerative response that becomes inadequate after large muscle loss or in degenerative pathologies and aging. In contrast, the mammalian heart loses its regenerative capacity shortly after birth, leaving it susceptible to permanent damage by acute injury or chronic disease. In this review, we compare and contrast the physiology and regenerative potential of native skeletal and cardiac muscles, mechanisms underlying striated muscle dysfunction, and bioengineering strategies to treat muscle disorders. We focus on different sources for cellular therapy, biomaterials to augment the endogenous regenerative response, and progress in engineering and application of mature striated muscle tissues in vitro and in vivo. Finally, we discuss the challenges and perspectives in translating muscle bioengineering strategies to clinical practice. PMID:27271751

  15. Detecting 22q11.2 deletion in Chinese children with conotruncal heart defects and single nucleotide polymorphisms in the haploid TBX1 locus

    Directory of Open Access Journals (Sweden)

    Xu Yue-Juan

    2011-12-01

    Full Text Available Abstract Background Conotruncal heart defects (CTDs are present in 75-85% of patients suffering from the 22q11.2 deletion syndrome. To date, no consistent phenotype has been consistently correlated with the 22q11.2 deletions. Genetic studies have implicated TBX1 as a critical gene in the pathogenesis of the syndrome. The aim of study was to determine the incidence of the 22q11.2 deletion in Chinese patients with CTDs and the possible mechanism for pathogenesis of CTDs. Methods We enrolled 212 patients with CTDs and 139 unrelated healthy controls. Both karyotypic analysis and multiplex ligation-dependent probe amplification were performed for all CTDs patients. Fluorescence in situ hybridization was performed for the patients with genetic deletions and their relatives. The TBX1 gene was sequenced for all patients and healthy controls. The χ2 and Fisher's exact test were used in the statistical analysis. Results Thirteen of the 212 patients with CTDs (6.13% were found to have the 22q11.2 deletion syndrome. Of the 13 cases, 11 presented with a hemizygous interstitial microdeletion from CLTCL1 to LZTR1; one presented with a regional deletion from CLTCL1 to DRCR8; and one presented with a regional deletion from CDC45L to LZTR1. There were eight sequence variants in the haploid TBX1 genes of the del22q11 CTDs patients. The frequency of one single nucleotide polymorphism (SNP in the del22q11 patients was different from that of the non-del patients (P P Conclusions CTDs, especially pulmonary atresia with ventricular septal defect and tetralogy of Fallot, are the most common disorders associated with the 22q11.2 deletion syndrome. Those patients with both CTDs and 22q11.2 deletion generally have a typical or atypical deletion region within the TBX1 gene. Our results indicate that TBX1 genetic variants may be associated with CTDs.

  16. [Effects of yiqi huoxue compound combined with exercise therapy on MMP-1 and collagen type III expressions of cardiac muscle in chronic heart failure rats].

    Science.gov (United States)

    Li, Hai; Zhang, Yan; Ma, Jin

    2011-07-01

    To study the effects and mechanisms of Yiqi Huoxue Compound combined with exercise therapy on the ventricular remodeling of chronic heart failure (CHF) rats after myocardial infarction. Eight rats were selected from sixty healthy SD rats as the blank control group, and the rest was used to prepare CHF rat model by coronary artery ligation in combination with exhausted swimming and food reducing. The successfully modeled rats were randomly divided into five groups, i. e., the model group (n = 8), the Chinese medicine group (n = 8), the Western medicine group (n = 8), the Chinese medicine + exercise group (n = 10), and the exercise group (n = 10). Routine gastrogavage of equal volume distilled water was given to rats in the blank control group and the model group respectively, 3 mL each time. Yiqi Huoxue Compound was given by gastrogavage to rats in the Chinese medicine group and the Chinese medicine + exercise group at the daily dose of 9.2 g crude drug/kg. Lisinopril was given by gastrogavage to rats in the Western medicine group at the daily dose of 1.5 mg crude drug/kg. The medication was administered twice daily for six successive weeks. The Chinese medicine + exercise group and the exercise group adopted exercise therapy, once daily. The myocardial tissue of rats' non-infarcted left ventricle was taken out. mRNA and protein contents of matrix metalloproteinase-1 (MMP-1) and collagen type III were detected by Real-time fluorescent quantitation PCR. Compared with the blank control group, the mRNA expression and the average gray value of MMP-1 increased, while those of collagen type III decreased in the model group, showing statistical difference (Pexercise group, showing statistical significance (Pexercise group. The mRNA expression and the average gray value of collagen type III increased in the Western medicine group and the Chinese medicine + exercise group, showing statistical difference (Pexercise therapy could attenuate the ventricular remodeling degree

  17. Eligibility of sacubitril-valsartan in a real-world heart failure population: a community-based single-centre study.

    Science.gov (United States)

    Norberg, Helena; Bergdahl, Ellinor; Lindmark, Krister

    2018-04-01

    This study aims to investigate the eligibility of the Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor (ARNI) with ACE inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) study to a real-world heart failure population. Medical records of all heart failure patients living within the catchment area of Umeå University Hospital were reviewed. This district consists of around 150 000 people. Out of 2029 patients with a diagnosis of heart failure, 1924 (95%) had at least one echocardiography performed, and 401 patients had an ejection fraction of ≤35% at their latest examination. The major PARADIGM-HF criteria were applied, and 95 patients fulfilled all enrolment criteria and thus were eligible for sacubitril-valsartan. This corresponds to 5% of the overall heart failure population and 24% of the population with ejection fraction ≤ 35%. The eligible patients were significantly older (73.2 ± 10.3 vs. 63.8 ± 11.5 years), had higher blood pressure (128 ± 17 vs. 122 ± 15 mmHg), had higher heart rate (77 ± 17 vs. 72 ± 12 b.p.m.), and had more atrial fibrillation (51.6% vs. 36.2%) than did the PARADIGM-HF population. Only 24% of our real-world heart failure and reduced ejection fraction population was eligible for sacubitril-valsartan, and the real-world heart failure and reduced ejection fraction patients were significantly older than the PARADIGM-HF population. The lack of data on a majority of the patients that we see in clinical practice is a real problem, and we are limited to extrapolation of results on a slightly different population. This is difficult to address, but perhaps registry-based randomized clinical trials will help to solve this issue. © 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  18. Construction of predictive models for recurrence and progression in >1000 patients with non-muscle-invasive bladder cancer (NMIBC) from a single centre.

    Science.gov (United States)

    Ali-El-Dein, Bedeir; Sooriakumaran, Prasanna; Trinh, Quoc-Dien; Barakat, Tamer S; Nabeeh, Adel; Ibrahiem, El-Housseiny I

    2013-06-01

    To construct predictive models based on the objectively calculated risks of progression and recurrence of non-muscle-invasive bladder cancer (NMIBC) in a large cohort of patients from a single centre. Between October 1984 and March 2009 a cohort of 1019 patients (877 males; 142 females; median age 44 years) with histologically confirmed NMIBC was included in this study. Among these patients, 74% received bacillus Calmette-Guérin (BCG)-based therapy. Complete transurethral resection of bladder tumour of all visible tumours was carried out in all patients, and the stage and grade were determined. Univariate analysis and multivariate Cox regression were used to identify predictors of recurrence and progression. The studied predictors included age, sex, stage, grade, associated carcinoma in situ, tumour size, multiplicity, macroscopic appearance of the tumour, history of recurrence and type of adjuvant intravesical therapy. Multivariate logistic regression models were used to develop the 12- and 60-month recurrence and progression predictive models. The predictive accuracy of the models was assessed for discrimination as well as calibration. The median (range) follow-up was 44 (6-254) months. On multivariate analysis, stage, multiplicity, history of recurrence and adjuvant intravesical therapy were significantly associated with recurrence, whereas for progression only tumour grade and size were significant independent predictors. The constructed nomograms had a 64.9% and 69.4% chance of correctly distinguishing between two patients, one destined to have a recurrence and one not at 12 and 60 months, respectively. The constructed nomograms had a 70.2% and 73.5% chance of correctly distinguishing between two patients, one destined to progress and one not at 12 and 60 months, respectively. All predictive models were well calibrated. Based on multivariate analysis of the studied prognostic factors nomograms for predicting recurrence and progression in NMIBC were

  19. Aspects on muscle properties and use in competitive Alpine skiing.

    Science.gov (United States)

    Tesch, P A

    1995-03-01

    This brief report describes the physiological demands in competitive Alpine skiing as well as the physiological profile of elite skiers. Maximal heart rate is typically attained by the end of either of the four Alpine ski disciplines. The giant slalom probably calls for the largest reliance upon aerobic energy metabolism and oxygen uptake may increase to 75%-100% of maximal aerobic power. Although high caliber skiers typically show increased maximal aerobic power, it is unlikely that this is an important factor determining success in skiing. Also, anaerobic energy provision accounts for more than half of the total energy yield. Accordingly, plasma and muscle lactate accumulation is substantial after a single race. Similarly, during skiing there is a high rate of glycogen utilization that eventually may result in depletion of muscle glycogen stores by the end of a day of intense skiing. Muscles of Alpine skiers do not possess a distinct fiber type composition and, if anything, skiers tend to show a preponderance of slow twitch fibers. This concords with the recruitment of both muscle fiber types during slalom or giant slalom. Elite skiers show increased knee extensor strength. This seems warranted because there is great reliance upon slow and forceful eccentric muscle actions when performing turns in the giant slalom or slalom.

  20. Deep soft-tissue massage applied to healthy calf muscle has no effect on passive mechanical properties: a randomized, single-blind, cross-over study.

    Science.gov (United States)

    Thomson, Daniel; Gupta, Amitabh; Arundell, Jesica; Crosbie, Jack

    2015-01-01

    Massage is often applied with the intention of improving flexibility or reducing stiffness in musculotendinous tissue. There is, however, a lack of supporting evidence that such mechanical effects occur. The purpose of the study was to investigate the effect of massage on the passive mechanical properties of the calf muscle complex. Twenty nine healthy volunteers aged between 18 and 45 years of age had their calf muscle compliance and ankle joint dorsiflexion range of motion (ROM) measured using an instrumented footplate before, immediately and 30 minutes after a ten minute application of deep massage or superficial heating to the calf muscle complex. Repeated measures analysis of variance was used to determine differences between testing sessions and the types of intervention. Reliability testing for the measurement method was conducted using analysis of variance both within and between testing sessions. There was no significant change in calf muscle stiffness or ankle dorsiflexion range of motion with or without the application of calf massage. Inter- and intra-session reliability were very high, ICC > 0.88 (p calf muscle complex. The findings of this study suggest that the use of massage to increase tissue flexibility prior to activity is not justified.

  1. Heart Failure

    DEFF Research Database (Denmark)

    Jorsal, Anders; Wiggers, Henrik; McMurray, John J V

    2018-01-01

    This article briefly discusses the epidemiology of heart failure and diabetes and summarizes the key findings from the recent cardiovascular outcome trials in patients with type 2 diabetes, with a focus on heart failure as an endpoint.......This article briefly discusses the epidemiology of heart failure and diabetes and summarizes the key findings from the recent cardiovascular outcome trials in patients with type 2 diabetes, with a focus on heart failure as an endpoint....

  2. A persistent increase in insulin-stimulated glucose uptake by both fast-twitch and slow-twitch skeletal muscles after a single exercise session by old rats.

    Science.gov (United States)

    Xiao, Yuanyuan; Sharma, Naveen; Arias, Edward B; Castorena, Carlos M; Cartee, Gregory D

    2013-06-01

    Exercise has been demonstrated to enhance subsequent insulin-stimulated glucose uptake (GU) by predominantly type II (fast-twitch) muscle of old rats, but previous research has not evaluated exercise effects on GU by type I (slow-twitch) muscle from old rats. Accordingly, we studied male Fischer 344/Brown Norway rats (24 months old) and determined GU (0, 100, 200, and 5,000 μU/ml insulin) of isolated soleus (predominantly type I) and epitrochlearis (predominantly type II) muscles after one exercise session. Epitrochlearis (100, 200, and 5,000 μU/ml insulin) and soleus (100 and 200 μU/ml insulin) GU were greater at 3-h postexercise vs. age-matched sedentary controls. Insulin receptor tyrosine phosphorylation (Tyr1162/1163) was unaltered by exercise in either muscle. Akt phosphorylation (pAkt) was greater for exercised vs. sedentary rats in the epitrochlearis (Ser473 and Thr308 with 100 and 200 μU/ml, respectively) and soleus (Ser473 with 200 μU/ml). AS160 phosphorylation (pAS160) was greater for exercised vs. sedentary rats in the epitrochlearis (Thr642 with 100 μU/ml), but not the soleus. Exercised vs. sedentary rats did not differ for total protein abundance of insulin receptor, Akt, AS160, or GLUT4 in either muscle. These results demonstrate that both predominantly type I and type II muscles from old rats are susceptible to exercise-induced improvement in insulin-mediated GU by mechanisms that are independent of enhanced insulin receptor tyrosine phosphorylation or altered abundance of important signaling proteins or GLUT4. Exercise-induced elevation in pAkt, and possibly pAS160, may contribute to this effect in the epitrochlearis of old rats, but other mechanisms are likely important for the soleus.

  3. Heart attack

    Science.gov (United States)

    ... part in support groups for people with heart disease . Outlook (Prognosis) After a heart attack, you have a higher ... P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, PA: Elsevier Saunders; 2014: ...

  4. MUSCLE ACTIVITY RESPONSE TO EXTERNAL MOMENT DURING SINGLE-LEG DROP LANDING IN YOUNG BASKETBALL PLAYERS: THE IMPORTANCE OF BICEPS FEMORIS IN REDUCING INTERNAL ROTATION OF KNEE DURING LANDING

    Directory of Open Access Journals (Sweden)

    Meguru Fujii

    2012-06-01

    Full Text Available Internal tibial rotation with the knee close to full extension combined with valgus collapse during drop landing generally results in non-contact anterior cruciate ligament (ACL injury. The purpose of this study was to investigate the relationship between internal rotation of the knee and muscle activity from internal and external rotator muscles, and between the internal rotation of knee and externally applied loads on the knee during landing in collegiate basketball players. Our hypothesis was that the activity of biceps femoris muscle would be an important factor reducing internal knee rotation during landing. The subjects were 10 collegiate basketball students: 5 females and 5 males. The subjects performed a single-leg drop landing from a 25-cm height. Femoral and tibial kinematics were measured using a 3D optoelectronic tracking system during the drop landings, and then the knee angular motions were determined. Ground reaction forces and muscle activation patterns (lateral hamstring and medial hamstring were simultaneously measured and computed. Results indicated that lower peak internal tibial rotation angle at the time of landing was associated with greater lateral hamstring activity (r = -0.623, p < 0.001. When gender was considered, the statistically significant correlation remained only in females. There was no association between the peak internal tibial rotation angle and the knee internal rotation moment. Control of muscle activity in the lateral to medial hamstring would be an important factor in generating sufficient force to inhibit excessive internal rotation during landing. Strengthening the biceps femoris might mitigate the higher incidence of non-contact ACL injury in female athletes

  5. Impact of the International Quality Improvement Collaborative on outcomes after congenital heart surgery: a single center experience in a developing economy.

    Science.gov (United States)

    Balachandran, Rakhi; Kappanayil, Mahesh; Sen, Amitabh Chanchal; Sudhakar, Abhish; Nair, Suresh G; Sunil, G S; Raj, R Benedict; Kumar, Raman Krishna

    2015-01-01

    The International Quality Improvement Collaborative (IQIC) for Congenital Heart Surgery in Developing Countries was initiated to decrease mortality and major complications after congenital heart surgery in the developing world. We sought to assess the impact of IQIC on postoperative outcomes after congenital heart surgery at our institution. The key components of the IQIC program included creation of a robust worldwide database on key outcome measures and nurse education on quality driven best practices using telemedicine platforms. We evaluated 1702 consecutive patients ≤18 years undergoing congenital heart surgery in our institute from January 2010-December 2012 using the IQIC database. Preoperative variables included age, gender, weight at surgery and surgical complexity as per the RACHS-1 model. The outcome variables included, in- hospital mortality, duration of ventilation, intensive care unit (ICU) stay, bacterial sepsis and surgical site infection. The 1702 patients included 771(45.3%) females. The median age was 8 months (0.03-216) and the median weight was 6.1Kg (1-100). The overall in-hospital mortality was 3.1%, Over the three years there was a significant decline in bacterial sepsis (from 15.1%, to 9.6%, P < 0.001), surgical site infection (11.1% to 2.4%, P < 0.001) and duration of ICU stay from 114(8-999) hours to 72 (18-999) hours (P < 0.001) The decline in mortality from (4.3% to 2.2%) did not reach statistical significance. The inclusion of our institution in the IQIC program was associated with improvement in key outcome measures following congenital heart surgery over a three year period.

  6. Impact of the International Quality Improvement Collaborative on outcomes after congenital heart surgery: A single center experience in a developing economy

    Directory of Open Access Journals (Sweden)

    Rakhi Balachandran

    2015-01-01

    Full Text Available Background: The International Quality Improvement Collaborative (IQIC for Congenital Heart Surgery in Developing Countries was initiated to decrease mortality and major complications after congenital heart surgery in the developing world. Objective: We sought to assess the impact of IQIC on postoperative outcomes after congenital heart surgery at our institution. Methods: The key components of the IQIC program included creation of a robust worldwide database on key outcome measures and nurse education on quality driven best practices using telemedicine platforms. We evaluated 1702 consecutive patients ≤18 years undergoing congenital heart surgery in our institute from January 2010-December 2012 using the IQIC database. Preoperative variables included age, gender, weight at surgery and surgical complexity as per the RACHS-1 model. The outcome variables included, in- hospital mortality, duration of ventilation, intensive care unit (ICU stay, bacterial sepsis and surgical site infection. Results: The 1702 patients included 771(45.3% females. The median age was 8 months (0.03-216 and the median weight was 6.1Kg (1-100. The overall in-hospital mortality was 3.1%, Over the three years there was a significant decline in bacterial sepsis (from 15.1%, to 9.6%, P < 0.001, surgical site infection (11.1% to 2.4%, P < 0.001 and duration of ICU stay from 114(8-999 hours to 72 (18-999 hours (P < 0.001 The decline in mortality from (4.3% to 2.2% did not reach statistical significance. Conclusions: The inclusion of our institution in the IQIC program was associated with improvement in key outcome measures following congenital heart surgery over a three year period.

  7. Separation of myoglobin and hemoglobin in isolated perfused pig heart

    Science.gov (United States)

    Rauh, Robert; Hiller, Michael; Trinks, Tobias; Kessler, Manfred D.

    2001-10-01

    For the quantitative determination of hemoglobin concentration in heart muscle it is important to distinguish between myoglobin and hemoglobin, two dyes with very similar optical absorption properties. With an isolated perfused pig heart model and EMPHO II SSK we measured tissue spectra in the visible range before and after adding erythrocytes to the perfusate. By calculating light intensity differences we were able to show spatial hemoglobin distribution in heart muscle.

  8. Sustained AS160 and TBC1D1 phosphorylations in human skeletal muscle 30 minutes after a single bout of exercise

    DEFF Research Database (Denmark)

    Vendelbo, Mikkel Holm; Møller, Andreas Buch; Treebak, Jonas Thue

    2014-01-01

    muscle after aerobic exercise followed by a hyperinsulinemic euglycemic clamp. Design: Eight healthy males were studied on two occasions: 1) in the resting state and 2) in the hours after a one-hour bout of ergometer-cycling. A hyperinsulinemic euglycemic clamp was initiated 240 minutes after exercise...

  9. Effect of cleft palate repair on the susceptibility to contraction-induced injury of single permeabilized muscle fibers from congenitally-clefted goat palates.

    Science.gov (United States)

    Despite cleft palate repair, velopharyngeal competence is not achieved in ~ 15% of patients, often necessitating secondary surgical correction. Velopharyngeal competence postrepair may require the conversion of levator veli palatini muscle fibers from injury-susceptible type 2 fibers to injury-resi...

  10. The contribution of inspiratory muscles function to exercise limitation in heart failure: pathophysiological mechanisms Contribuição da musculatura inspiratória na limitação ao exercício na insuficiência cardíaca: mecanismos fisiopatológicos

    Directory of Open Access Journals (Sweden)

    Jorge P. Ribeiro

    2012-08-01

    Full Text Available BACKGROUND: Heart failure induces histological, metabolic and functional adaptations in the inspiratory muscles. This inspiratory muscle weakness, which occurs in 30% to 50% of the heart failure patients, is associated with reduction in the functional capacity, reduction in the quality of life and with a poor prognosis in these individuals. OBJECTIVES: The objective of this review was to discuss the pathophysiological mechanisms that may explain the role of the inspiratory muscles in the exercise limitation with focus in the reflexes that control the ventilation and the circulation during the exercise. METHOD: We performed searches in the PUBMED database using the terms "inspiratory muscles", "inspiratory muscle training", "metaboreflex" and chemoreflex" and including studies published since 1980. RESULTS: Inspiratory muscle weakness is associated with exercise intolerance and with an exaggerated inspiratory chemoreflex and metaboreflex in heart failure. The inspiratory metaboreflex may be attenuated by the inspiratory muscle training or by the aerobic exercise training improving the exercise performance. CONCLUSIONS: Patients with heart failure may present changes in the inspiratory muscle function associated with inspiratory chemoreflex and metaboreflex hyperactivity, which exacerbate the exercise intolerance.CONTEXTUALIZAÇÃO: A insuficiência cardíaca (IC acarreta alterações histológicas, metabólicas e funcionais dos músculos inspiratórios. A fraqueza dos músculos inspiratórios, que ocorre em 30% a 50% dos pacientes com IC, associa-se com a redução da capacidade funcional, prejuízos para a qualidade de vida e piora no prognóstico desses indivíduos. OBJETIVOS: Discutir os mecanismos fisiopatológicos que potencialmente explicam o papel da musculatura inspiratória na limitação ao exercício, abordando-se os reflexos que controlam a ventilação e a circulação durante o exercício. MÉTODO: Foram realizadas pesquisas na base

  11. Increased type I collagen content and DNA binding activity of a single-stranded, cytosine-rich sequence in the high-salt buffer protein extract of the copper-deficient rat heart.

    Science.gov (United States)

    Zeng, Huawei; Saari, Jack T

    2004-11-01

    Dietary copper (Cu) deficiency not only causes a hypertrophic cardiomyopathy but also increases cancer risk in rodent models. However, a possible alteration in gene expression has not been fully examined. The present study was undertaken to determine the effect of Cu deficiency on protein profiles in rat heart tissue. Male Sprague-Dawley rats were fed diets that were either a Cu-adequate diet (6.0 microg Cu/g diet, n = 6) or a Cu-deficient diet (0.3 microg Cu/g diet, n = 6) for 5 weeks. The high-salt buffer (HSB) protein extract from heart tissue of Cu-deficient, but not Cu-adequate rats showed a 132 kDa protein band by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. This protein band stained pink with Coomassie Blue, suggesting the presence of collagens or other proline-rich proteins. Dot immunoblotting demonstrated that total type I collagen was increased by 110% in HSB protein extract from Cu-deficient, relative to Cu-adequate, rats. Liquid chromatography with mass spectrometry analysis indicated that the 132 kDa protein band contained a collagen alpha (I) chain precursor as well as a leucine-rich protein 130 (LRP130) in HSB protein extract from Cu-deficient but not Cu-adequate rats. A gel shift assay showed that HSB protein extract from Cu-deficient rats bound to a single-stranded cytosine-rich DNA with higher affinity than the extract of Cu-adequate rats, similar to reports of an increase in LRP130 single-stranded DNA binding activity in several types of tumor cells. Collectively, these results not only suggest an additional feature of altered collagen metabolism with Cu deficiency but also demonstrate for the first time an increase in single-stranded cytosine-rich DNA binding in Cu-deficient rat heart.

  12. Dystrophic calcification in muscles of legs in calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia syndrome: Accurate evaluation of the extent with (99m)Tc-methylene diphosphonate single photon emission computed tomography/computed tomography.

    Science.gov (United States)

    Chakraborty, Partha Sarathi; Karunanithi, Sellam; Dhull, Varun Singh; Kumar, Kunal; Tripathi, Madhavi

    2015-01-01

    We present the case of a 35-year-old man with calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly and telangiectasia variant scleroderma who presented with dysphagia, Raynaud's phenomenon and calf pain. (99m)Tc-methylene diphosphonate bone scintigraphy was performed to identify the extent of the calcification. It revealed extensive dystrophic calcification in the left thigh and bilateral legs which was involving the muscles and was well-delineated on single photon emission computed tomography/computed tomography. Calcinosis in scleroderma usually involves the skin but can be found in deeper periarticular tissues. Myopathy is associated with a poor prognosis.

  13. Prenatal Detection of Congenital Heart Diseases: One-Year Survey Performing a Screening Protocol in a Single Reference Center in Brazil

    Directory of Open Access Journals (Sweden)

    Luciane Alves Rocha

    2014-01-01

    Full Text Available Objective. To describe the experience of a tertiary center in Brazil to which patients are referred whose fetuses are at increased risk for congenital heart diseases (CHDs. Methods. This was a cross-sectional observational study. The data was collected prospectively, during the year 2012, through a screening protocol of the fetal heart adapted from the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG guideline. We performed a fetal echocardiogram screening for all pregnant women who were referred to the fetal cardiology outpatient obstetrics clinic of a university hospital. The exams were classified as normal or abnormal. The cases considered abnormal were undergone to a postnatal echocardiogram. We categorized the abnormal fetal heart according to severity in “complex,” “significant,” “minor,” and “others.” Results. We performed 271 fetal heart screening. The incidence of abnormal screenings was 9.96% (27 fetuses. The structural CHD when categorized due to severity showed 48.1% (n=13 of “complex” cases, 18.5% (n=5 “significant” cases, and 7.4% (n=2 “minor” cases. The most common referral reason was by maternal causes (67% followed by fetal causes (33%. The main referral indication was maternal metabolic disease (30%, but there was just one fetus with CHD in such cases (1.2%. CHDs were found in 19/29 fetuses with suspicion of some cardiac abnormality by obstetrician (65.5%. Conclusion. We observed a high rate of CHD in our population. We also found that there was higher incidence of complex cases.

  14. Water and Muscle Contraction

    Directory of Open Access Journals (Sweden)

    Enrico Grazi

    2008-08-01

    Full Text Available The interaction between water and the protein of the contractile machinery as well as the tendency of these proteins to form geometrically ordered structures provide a link between water and muscle contraction. Protein osmotic pressure is strictly related to the chemical potential of the contractile proteins, to the stiffness of muscle structures and to the viscosity of the sliding of the thin over the thick filaments. Muscle power output and the steady rate of contraction are linked by modulating a single parameter, a viscosity coefficient. Muscle operation is characterized by working strokes of much shorter length and much quicker than in the classical model. As a consequence the force delivered and the stiffness attained by attached cross-bridges is much larger than usually believed.

  15. Does giving segmental muscle vibration alter the response to botulinum toxin injections in the treatment of spasticity in people with multiple sclerosis? A single-blind randomized controlled trial.

    Science.gov (United States)

    Paoloni, Marco; Giovannelli, Morena; Mangone, Massimiliano; Leonardi, Laura; Tavernese, Emanuela; Di Pangrazio, Elisabetta; Bernetti, Andrea; Santilli, Valter; Pozzilli, Carlo

    2013-09-01

    To determine if segmental muscle vibration and botulinum toxin-A injection, either alone or in combination, reduces spasticity in a sample of patients with multiple sclerosis. Single-blind, randomized controlled trial. Physical medicine and rehabilitation outpatients service. Forty-two patients affected by the secondary progressive form of multiple sclerosis randomized to group A (30 minutes of 120 Hz segmental muscle vibration over the rectus femoris and gastrocnemius medial and lateral, three per week, over a period of four weeks), group B (botulinum toxin in the rectus femoris, gastrocnemius medial and lateral and soleus, and segmental muscle vibration) and group C (botulinum toxin). Modified Ashworth Scale at knee and ankle, and Fatigue Severity Scale. All the measurements were performed at baseline (T0), 10 weeks (T1) and 22 weeks (T2) postallocation. Modified Ashworth Scale at knee and ankle significantly decreased over time (p spasticity at T2 when compared with T1 (p spasticity and improves fatigue in the medium-term follow-up in patients with multiple sclerosis.

  16. RNA sequencing for global gene expression associated with muscle growth in a single male modern broiler line compared to a foundational Barred Plymouth Rock chicken line.

    Science.gov (United States)

    Kong, Byung-Whi; Hudson, Nicholas; Seo, Dongwon; Lee, Seok; Khatri, Bhuwan; Lassiter, Kentu; Cook, Devin; Piekarski, Alissa; Dridi, Sami; Anthony, Nicholas; Bottje, Walter

    2017-01-13

    Modern broiler chickens exhibit very rapid growth and high feed efficiency compared to unselected chicken breeds. The improved production efficiency in modern broiler chickens was achieved by the intensive genetic selection for meat production. This study was designed to investigate the genetic alterations accumulated in modern broiler breeder lines during selective breeding conducted over several decades. To identify genes important in determining muscle growth and feed efficiency in broilers, RNA sequencing (RNAseq) was conducted with breast muscle in modern pedigree male (PeM) broilers (n = 6 per group), and with an unselected foundation broiler line (Barred Plymouth Rock; BPR). The RNAseq analysis was carried out using Ilumina Hiseq (2 x 100 bp paired end read) and raw reads were assembled with the galgal4 reference chicken genome. With normalized RPM values, genes showing >10 average read counts were chosen and genes showing 1.3 fold change were considered as differentially expressed (DE) between PeM and BPR. DE genes were subjected to Ingenuity Pathway Analysis (IPA) for bioinformatic functional interpretation. The results indicate that 2,464 DE genes were identified in the comparison between PeM and BPR. Interestingly, the expression of genes encoding mitochondrial proteins in chicken are significantly biased towards the BPR group, suggesting a lowered mitochondrial content in PeM chicken muscles compared to BPR chicken. This result is inconsistent with more slow muscle fibers bearing a lower mitochondrial content in the PeM. The molecular, cellular and physiological functions of DE genes in the comparison between PeM and BPR include organismal injury, carbohydrate metabolism, cell growth/proliferation, and skeletal muscle system development, indicating that cellular mechanisms in modern broiler lines are tightly associated with rapid growth and differential muscle fiber contents compared to the unselected BPR line. Particularly, PDGF (platelet derived

  17. Enhanced skeletal muscle ribosome biogenesis, yet attenuated mTORC1 and ribosome biogenesis-related signalling, following short-term concurrent versus single-mode resistance training.

    Science.gov (United States)

    Fyfe, Jackson J; Bishop, David J; Bartlett, Jonathan D; Hanson, Erik D; Anderson, Mitchell J; Garnham, Andrew P; Stepto, Nigel K

    2018-01-12

    Combining endurance training with resistance training (RT) may attenuate skeletal muscle hypertrophic adaptation versus RT alone; however, the underlying mechanisms are unclear. We investigated changes in markers of ribosome biogenesis, a process linked with skeletal muscle hypertrophy, following concurrent training versus RT alone. Twenty-three males underwent eight weeks of RT, either performed alone (RT group, n = 8), or combined with either high-intensity interval training (HIT+RT group, n = 8), or moderate-intensity continuous training (MICT+RT group, n = 7). Muscle samples (vastus lateralis) were obtained before training, and immediately before, 1 h and 3 h after the final training session. Training-induced changes in basal expression of the 45S ribosomal RNA (rRNA) precursor (45S pre-rRNA), and 5.8S and 28S mature rRNAs, were greater with concurrent training versus RT. However, during the final training session, RT further increased both mTORC1 (p70S6K1 and rps6 phosphorylation) and 45S pre-rRNA transcription-related signalling (TIF-1A and UBF phosphorylation) versus concurrent training. These data suggest that when performed in a training-accustomed state, RT induces further increases mTORC1 and ribosome biogenesis-related signalling in human skeletal muscle versus concurrent training; however, changes in ribosome biogenesis markers were more favourable following a period of short-term concurrent training versus RT performed alone.

  18. Power Production and Biochemical Markers of Metabolic Stress and Muscle Damage Following a Single Bout of Short-Sprint and Heavy Strength Exercise in Well-Trained Cyclists

    Directory of Open Access Journals (Sweden)

    Morten Kristoffersen

    2018-03-01

    Full Text Available Purpose: Although strength and sprint training are widely used methods in competitive cycling, no previous studies have compared the acute responses and recovery rates following such sessions among highly trained cyclists. The primary aim of the current study was to compare power production and biochemical markers of metabolic stress and muscle damage following a session of heavy strength (HS and short-sprint training (SS.Methods: Eleven well-trained male cyclists (18 ± 2 years with maximal oxygen uptake of 67.2 ± 5.0 mL·kg−1·min−1 completed one HS session and one SS session in a randomized order, separated by 48 h. Power production and biochemical variables were measured at baseline and at different time points during the first 45 h post exercise.Results: Lactate and human growth hormone were higher 5 min, 30 min and 1 h post the SS compared to the HS session (all p ≤ 0.019. Myoglobin was higher following the HS than the SS session 5 min, 30 min and 1 h post exercise (all p ≤ 0.005, while creatine kinase (CK was higher following the HS session 21 and 45 h post exercise (p ≤ 0.038. Counter movement jump and power production during 4 sec sprint returned to baseline levels at 23 and 47 h with no difference between the HS and SS session, whereas the delayed muscle soreness score was higher 45 h following the HS compared to the SS session (p = 0.010.Conclusion: Our findings indicate that SS training provides greater metabolic stress than HS training, whereas HS training leads to more muscle damage compared to that caused by SS training. The ability to produce power remained back to baseline already 23 h after both training sessions, indicating maintained performance levels although higher CK level and muscle soreness were present 45 h post the HS training session.

  19. Improved Muscle Function in Duchenne Muscular Dystrophy through L-Arginine and Metformin: An Investigator-Initiated, Open-Label, Single-Center, Proof-Of-Concept-Study.

    Science.gov (United States)

    Hafner, Patricia; Bonati, Ulrike; Erne, Beat; Schmid, Maurice; Rubino, Daniela; Pohlman, Urs; Peters, Thomas; Rutz, Erich; Frank, Stephan; Neuhaus, Cornelia; Deuster, Stefanie; Gloor, Monika; Bieri, Oliver; Fischmann, Arne; Sinnreich, Michael; Gueven, Nuri; Fischer, Dirk

    2016-01-01

    Altered neuronal nitric oxide synthase function in Duchenne muscular dystrophy leads to impaired mitochondrial function which is thought to be one cause of muscle damage in this disease. The study tested if increased intramuscular nitric oxide concentration can improve mitochondrial energy metabolism in Duchenne muscular dystrophy using a novel therapeutic approach through the combination of L-arginine with metformin. Five ambulatory, genetically confirmed Duchenne muscular dystrophy patients aged between 7–10 years were treated with L-arginine (3 x 2.5 g/d) and metformin (2 x 250 mg/d) for 16 weeks. Treatment effects were assessed using mitochondrial protein expression analysis in muscular biopsies, indirect calorimetry, Dual-Energy X-Ray Absorptiometry, quantitative thigh muscle MRI, and clinical scores of muscle performance. There were no serious side effects and no patient dropped out. Muscle biopsy results showed pre-treatment a significantly reduced mitochondrial protein expression and increased oxidative stress in Duchenne muscular dystrophy patients compared to controls. Post-treatment a significant elevation of proteins of the mitochondrial electron transport chain was observed as well as a reduction in oxidative stress. Treatment also decreased resting energy expenditure rates and energy substrate use shifted from carbohydrates to fatty acids. These changes were associated with improved clinical scores. In conclusion pharmacological stimulation of the nitric oxide pathway leads to improved mitochondria function and clinically a slowing of disease progression in Duchenne muscular dystrophy. This study shall lead to further development of this novel therapeutic approach into a real alternative for Duchenne muscular dystrophy patients. ClinicalTrials.gov NCT02516085.

  20. Comparison of the effects of knee and hip and single knee muscles strengthening/ stretching exercises on pain intensity and function in athletes with patellofemoral pain syndrome

    Directory of Open Access Journals (Sweden)

    Vahid Mazloum

    2016-08-01

    Full Text Available Background: Patellofemoral pain syndrome (PFPS is a common musculoskeletal condition among athletes. The evidence emphasizes on the importance of hip musculature strengthening exercises for such patients. Objective: To investigate the effects of strengthening-stretching knee muscles exercises and hip posterolateral musculature exercises in athletes with PFPS. Methods: In this clinical trial, 28 athletes with age average of 22.7±2.4 years with PFPS were allocated into conventional knee muscles exercises (CKME (n=14 and posterolateral hip muscles exercises (PHME (n=14. The subjects of both groups performed the supervised exercise protocols in 12 sessions. The Visual Analogue Scale and 6-minute walking tests were administrated respectively to evaluate pain intensity and function. The data were analyzed using Shapiro-wilk test, Independent-sample t test, and Repeated Measure ANOVA test. Findings: Demographic, pain intensity, and physical function data were similar between groups at baseline. Both groups significantly improved in pain intensity and function following a 4-week exercise program. Additionally, the athletes in PHME group had higher level of decreased pain intensity and improved function in follow-up assessment than the subjects in CKME group. Conclusion: Using hip posterolateral musculature exercises in addition to the knee conventional exercises is more effective for athletes with PFPS.

  1. Mechanics of Vascular Smooth Muscle.

    Science.gov (United States)

    Ratz, Paul H

    2015-12-15

    Vascular smooth muscle (VSM; see Table 1 for a list of abbreviations) is a heterogeneous biomaterial comprised of cells and extracellular matrix. By surrounding tubes of endothelial cells, VSM forms a regulated network, the vasculature, through which oxygenated blood supplies specialized organs, permitting the development of large multicellular organisms. VSM cells, the engine of the vasculature, house a set of regulated nanomotors that permit rapid stress-development, sustained stress-maintenance and vessel constriction. Viscoelastic materials within, surrounding and attached to VSM cells, comprised largely of polymeric proteins with complex mechanical characteristics, assist the engine with countering loads imposed by the heart pump, and with control of relengthening after constriction. The complexity of this smart material can