Aerobic exercise and respiratory muscle strength in patients with cystic fibrosis.

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Dassios, Theodore; Katelari, Anna; Doudounakis, Stavros; Dimitriou, Gabriel

2013-05-01

The beneficial role of exercise in maintaining health in patients with cystic fibrosis (CF) is well described. Few data exist on the effect of exercise on respiratory muscle function in patients with CF. Our objective was to compare respiratory muscle function indices in CF patients that regularly exercise with those CF patients that do not. This cross-sectional study assessed nutrition, pulmonary function and respiratory muscle function in 37 CF patients that undertook regular aerobic exercise and in a control group matched for age and gender which consisted of 44 CF patients that did not undertake regular exercise. Respiratory muscle function in CF was assessed by maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax) and pressure-time index of the respiratory muscles (PTImus). Median Pimax and Pemax were significantly higher in the exercise group compared to the control group (92 vs. 63 cm H2O and 94 vs. 64 cm H2O respectively). PTImus was significantly lower in the exercise group compared to the control group (0.089 vs. 0.121). Upper arm muscle area (UAMA) and mid-arm muscle circumference were significantly increased in the exercise group compared to the control group (2608 vs. 2178 mm2 and 23 vs. 21 cm respectively). UAMA was significantly related to Pimax in the exercising group. These results suggest that CF patients that undertake regular aerobic exercise maintain higher indices of respiratory muscle strength and lower PTImus values, while increased UAMA values in exercising patients highlight the importance of muscular competence in respiratory muscle function in this population. Copyright © 2013 Elsevier Ltd. All rights reserved.

Respiratory muscle strength is not decreased in patients undergoing cardiac surgery.

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Urell, Charlotte; Emtner, Margareta; Hedenstrom, Hans; Westerdahl, Elisabeth

2016-03-31

Postoperative pulmonary impairments are significant complications after cardiac surgery. Decreased respiratory muscle strength could be one reason for impaired lung function in the postoperative period. The primary aim of this study was to describe respiratory muscle strength before and two months after cardiac surgery. A secondary aim was to describe possible associations between respiratory muscle strength and lung function. In this prospective observational study 36 adult cardiac surgery patients (67 ± 10 years) were studied. Respiratory muscle strength and lung function were measured before and two months after surgery. Pre- and postoperative respiratory muscle strength was in accordance with predicted values; MIP was 78 ± 24 cmH2O preoperatively and 73 ± 22 cmH2O at two months follow-up (p = 0.19). MEP was 122 ± 33 cmH2O preoperatively and 115 ± 38 cmH2O at two months follow-up (p = 0.18). Preoperative lung function was in accordance with predicted values, but was significantly decreased postoperatively. At two-months follow-up there was a moderate correlation between MIP and FEV1 (r = 0.43, p = 0.009). Respiratory muscle strength was not impaired, either before or two months after cardiac surgery. The reason for postoperative lung function alteration is not yet known. Interventions aimed at restore an optimal postoperative lung function should focus on other interventions then respiratory muscle strength training.

Physical activity and respiratory muscle strength in elderly: a systematic review

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Fabio Dutra Pereira

Full Text Available Introduction The aging will inevitably bring some kind of functional decline in elderly, sarcopenia in this sense stands out because it damages the muscle function and extend also to the respiratory muscles. Objective Systematically review studies that have sought to compare the strength of respiratory muscles between sedentary and physically active elderly in training programs nonspecific respiratory musculature. Materials and methods From the descriptors motor activity, respiratory muscles and elderly, the databases LILACS, MedLine, Cochrane, PEDro, Scirus and Redalyc were consulted. Results Of 1.263 experiments available in said databases, 12 were recovered and 6 were selected due they meet all the inclusion criteria and selection requirements. Conclusion Physical activity programs offered by the selected studies led physically active elderly to have respiratory muscle strength statistically higher than the sedentary. However, this condition did not expressed itself as security to these elderly to present strength levels above of the minimum predictive of normality.

Respiratory muscle weakness and respiratory muscle training in severely disabled multiple sclerosis patients.

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Gosselink, R; Kovacs, L; Ketelaer, P; Carton, H; Decramer, M

2000-06-01

To evaluate the contribution of respiratory muscle weakness (part 1) and respiratory muscle training (part 2) to pulmonary function, cough efficacy, and functional status in patients with advanced multiple sclerosis (MS). Survey (part 1) and randomized controlled trial (part 2). Rehabilitation center for MS. Twenty-eight bedridden or wheelchair-bound MS patients (part 1); 18 patients were randomly assigned to a training group (n = 9) or a control group (n = 9) (part 2). The training group (part 2) performed three series of 15 contractions against an expiratory resistance (60% maximum expiratory pressure [PEmax]) two times a day, whereas the control group performed breathing exercises to enhance maximal inspirations. Forced vital capacity (FVC), inspiratory, and expiratory muscle strength (PImax and PEmax), neck flexion force (NFF), cough efficacy by means of the Pulmonary Index (PI), and functional status by means of the Extended Disability Status Scale (EDSS). Part 1 revealed a significantly reduced FVC (43% +/- 26% predicted), PEmax (18% +/- 8% predicted), and PImax (27% +/- 11% predicted), whereas NFF was only mildly reduced (93% +/- 26% predicted). The PI (median score, 10) and EDSS (median score, 8.5) were severely reduced. PEmax was significantly correlated to FVC, EDSS, and PI (r = .77, -.79, and -.47, respectively). In stepwise multiple regression analysis. PEmax was the only factor contributing to the explained variance in FVC (R2 = .60), whereas body weight (R2 = .41) was the only factor for the PI. In part 2, changes in PImax and PEmax tended to be higher in the training group (p = .06 and p = .07, respectively). The PI was significantly improved after 3 months of training compared with the control group (p functional status. Expiratory muscle training tended to enhance inspiratory and expiratory muscle strength. In addition, subjectively and objectively rated cough efficacy improved significantly and lasted for 3 months after training cessation.

Activation of respiratory muscles during weaning from mechanical ventilation.

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Walterspacher, Stephan; Gückler, Julia; Pietsch, Fabian; Walker, David Johannes; Kabitz, Hans-Joachim; Dreher, Michael

2017-04-01

Respiratory muscle dysfunction is a key component of weaning failure. Balancing respiratory muscle loading and unloading by applying different ventilation modes along with spontaneous breathing episodes are established weaning strategies. However, the effects of body positioning on the respiratory muscles during weaning remains unclear. This study aimed at assessing respiratory drive by surface electromyography (EMG) of the diaphragm (EMG dia ) and parasternal muscles (EMG para ) in tracheotomized patients during prolonged weaning in 3 randomized body positions-supine, 30° semirecumbent, and 80° sitting-during mechanical ventilation and spontaneous breathing. Nine patients were included for analysis. Cardiorespiratory parameters (heart rate, blood pressure, arterial oxygen saturation, dyspnea) did not change under each condition (all P>.05). EMG para and EMG dia did not change under mechanical ventilation (both P>.05). EMG dia changed under spontaneous breathing from supine to sitting (0.45±0.26 vs 0.32±0.19; P=.012) and between semirecumbent to sitting (0.41±0.23 vs 0.32±0.19; P=.039), whereas EMG para did not change. This is the first study to show that body positioning influences respiratory drive to the diaphragm in tracheotomized patients with prolonged weaning from mechanical ventilation during unassisted breathing. Sitting position reduces respiratory drive compared with semirecumbent and supine positioning and might therefore be favored during spontaneous breathing trials. Copyright © 2016 Elsevier Inc. All rights reserved.

Respiratory muscle function and exercise limitation in patients with chronic obstructive pulmonary disease: a review.

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Charususin, Noppawan; Dacha, Sauwaluk; Gosselink, Rik; Decramer, Marc; Von Leupoldt, Andreas; Reijnders, Thomas; Louvaris, Zafeiris; Langer, Daniel

2018-01-01

Respiratory muscle dysfunction is common and contributes to dyspnea and exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Improving dynamic function of respiratory muscles during exercise might help to reduce symptoms and improve exercise capacity. Areas covered: The aims of this review are to 1) summarize physiological mechanisms linking respiratory muscle dysfunction to dyspnea and exercise limitation; 2) provide an overview of available therapeutic approaches to better maintain load-capacity balance of respiratory muscles during exercise; and 3) to summarize current knowledge on potential mechanisms explaining effects of interventions aimed at optimizing dynamic respiratory muscle function with a special focus on inspiratory muscle training. Expert commentary: Several mechanisms which are potentially linking improvements in dynamic respiratory muscle function to symptomatic and functional benefits have not been studied so far in COPD patients. Examples of underexplored areas include the study of neural processes related to the relief of acute dyspnea and the competition between respiratory and peripheral muscles for limited energy supplies during exercise. Novel methodologies are available to non-invasively study these mechanisms. Better insights into the consequences of dynamic respiratory muscle dysfunction will hopefully contribute to further refine and individualize therapeutic approaches in patients with COPD.

Respiratory muscle stretch gymnastics in patients with post coronary artery bypass grafting pain : Impact on respiratory muscle function, activity, mood and exercise capacity

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會田, 信子; 渋谷, 優子; 吉野, 克樹; Komoda, Masaji; 井上, 智子

2002-01-01

A new rehabilitation (New-RH) program including respiratory muscle stretch gymnastics (RMSG) was developed to alleviate post-coronary artery bypass grafting pain (PCP). Effects on respiratory muscle function, pain, activities of daily living (ADL), mood and exercise capacity were investigated. Subjects were 16 consecutive patients undergoing median full sternotomy coronary artery bypass grafting (CABG), and were randomly divided into equal New-RH (S-group) and conventional therapy (C-group) g...

Respiratory muscle training for multiple sclerosis

NARCIS (Netherlands)

Rietberg, Marc B.; Veerbeek, Janne M.; Gosselink, Rik; Kwakkel, Gert; van Wegen, Erwin E.H.

2017-01-01

Background: Multiple sclerosis (MS) is a chronic disease of the central nervous system, affecting approximately 2.5 million people worldwide. People with MS may experience limitations in muscular strength and endurance - including the respiratory muscles, affecting functional performance and

Respiratory muscle function in infants with spinal muscular atrophy type I.

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Finkel, Richard S; Weiner, Daniel J; Mayer, Oscar H; McDonough, Joseph M; Panitch, Howard B

2014-12-01

To determine the feasibility and safety of respiratory muscle function testing in weak infants with a progressive neuromuscular disorder. Respiratory insufficiency is the major cause of morbidity and mortality in infants with spinal muscular atrophy type I (SMA-I). Tests of respiratory muscle strength, endurance, and breathing patterns can be performed safely in SMA-I infants. Useful data can be collected which parallels the clinical course of pulmonary function in SMA-I. An exploratory study of respiratory muscle function testing and breathing patterns in seven infants with SMA-I seen in our neuromuscular clinic. Measurements were made at initial study visit and, where possible, longitudinally over time. We measured maximal inspiratory (MIP) and transdiaphragmatic pressures, mean transdiaphragmatic pressure, airway occlusion pressure at 100 msec of inspiration, inspiratory and total respiratory cycle time, and aspects of relative thoracoabdominal motion using respiratory inductive plethysmography (RIP). The tension time index of the diaphragm and of the respiratory muscles, phase angle (Φ), phase relation during the total breath, and labored breathing index were calculated. Age at baseline study was 54-237 (median 131) days. Reliable data were obtained safely for MIP, phase angle, labored breathing index, and the invasive and non-invasive tension time indices, even in very weak infants. Data obtained corresponded to the clinical estimate of severity and predicted the need for respiratory support. The testing employed was both safe and feasible. Measurements of MIP and RIP are easily performed tests that are well tolerated and provide clinically useful information for infants with SMA-I. © 2014 Wiley Periodicals, Inc.

Effectiveness of water-based Liuzijue exercise on respiratory muscle strength and peripheral skeletal muscle function in patients with COPD

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Wu W

2018-05-01

Full Text Available Weibing Wu,1,* Xiaodan Liu,2,* Jingxin Liu,1 Peijun Li,1 Zhenwei Wang3 1Department of Sports Medicine, Shanghai University of Sport, 2School of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine, 3Department of Respiratory Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Objects: The purpose of this study was to quantitatively assess the effects of water-based Liuzijue exercise on patients with COPD and compare it with land-based Liuzijue exercise.Materials and methods: Participants were randomly allocated to one of three groups: the water-based Liuzijue exercise group (WG, the land-based Liuzijue exercise group (LG, and the control group (CG. CG participants accepted no exercise intervention, while training groups performed Liuzijue exercise according to Health Qigong Liuzijue (People’s Republic of China in different environments for 60-min sessions twice a week for 3 months.Results: Of the 50 patients enrolled, 45 (90% completed the 3-month intervention. The CG showed decreased expiratory muscle strength, extensor and flexor endurance ratio (ER of the elbow joints and flexor peak torque (PT, total work (TW, and ER of the knee joints (p<0.05. Both training groups showed improved respiratory muscle strength, which differed from the CG (p<0.001. In addition, extensor and flexor TW of the elbow joints in the training groups were increased (p<0.01, and the WG differed from the CG in extensor TW and ER and flexor TW (p<0.01, while the LG differed from the CG in flexor TW and extensor ER (p<0.05. PT, PT/body weight (BW, and TW in the knee joint extensor in the training groups were increased as well (PT and PT/BW: p<0.05, TW: p<0.01, and the WG differed from the CG in terms of knee joints outcomes, while the LG differed from the CG in flexor TW only (p<0.05.Conclusion: Water-based Liuzijue exercise has

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

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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

Hippotherapy and respiratory muscle strength in children and adolescents with Down syndrome

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Valéria Sovat de Freitas Costa

Full Text Available Introduction Individuals with Down syndrome may have decreased respiratory muscle strength due to hypotonia, a common characteristic in this population. Objective To analyze the effects of a hippotherapy program on respiratory muscle strength in individuals with Down syndrome. Materials and methods The study included 41 subjects, 20 of which were in the hippotherapy practicing group (PG and 21 of which were in the non-practicing group (NPG. Study subjects were of both sexes, aged 7-13 years, and all diagnosed with Down syndrome. A manovacuometer was used to measure respiratory muscle strength, following the protocol proposed by Black and Hyatt (23. Statistical analysis was performed by means of descriptive distribution. After verifying normality and homoscedasticity of the variables, the Mann-Whitney test was used to determine differences between the means of the two groups (PG and NPG, and the Spearman’s rank correlation coefficient test was used to view possible relationships with age and time practicing hippotherapy. Significance was set at p < 0.05. Results and discussion Individuals who practiced hippotherapy showed improvements in both inspiratory and expiratory respiratory muscle strength, although no significant difference was demonstrated. Conclusion This study demonstrates that hippotherapy benefits respiratory muscle strength in individuals with Down syndrome, and that the youngest subjects had the best results.

Respiratory muscle strength of patients with esophagus and stomach neoplasms

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Evelyn Aline Boscolo Ruivo

Full Text Available Abstract Introduction: In cancer patients, the reduced food intake causes weight loss and promotes protein-calorie malnutrition. This results in loss of lean body mass, which affects both skeletal muscles and respiratory muscles. Objective: Evaluate and compare the respiratory muscle strength of patients with esophageal and stomach neoplasia during the preoperative period. Methods: This is a cross-sectional study carried out with 24 patients of both genders hospitalized in a teaching hospital. They underwent a physical therapy evaluation composed of anthropometric data and measurement of respiratory muscle strength through manovacuometry. Paired and unpaired t-tests were used to compare the values obtained with the predicted equations. Results: Regarding the disease prevalence, 66.66%(16 of the individuals had stomach neoplasm and 33.33%(8 esophageal neoplasm. Of the patients with esophageal neoplasm, 100% were men with a mean age of 63 ± 9.16 years. Of those with stomach neoplasm, 68.75% were men with a mean age of 69.36 ± 10.92 years. Female patients with stomach neoplasm had significantly higher BMI (p = 0.01 than male patients, and they were classified as overweight. Both neoplasms had significantly lower real values (p ≤ 0.05 than predicted values at the maximal expiratory pressure. Conclusion: Patients with esophageal and stomach neoplasms in the preoperative period present reduction in the expiratory muscle strength. There were no statistically significant differences, when we compared the maximum respiratory pressures between the two types of neoplasms investigated.

DiapHRaGM: A mnemonic to describe the work of breathing in patients with respiratory failure.

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Aiman Tulaimat

Full Text Available The assessment of the work of breathing in the definitions of respiratory failure is vague and variable.Identify a parsimonious set of signs to describe the work of breathing in hypoxemic, acutely ill patients.We examined consecutive medical ICU patients receiving oxygen with a mask, non-invasive ventilation, or T-piece. A physician inspected each patient for 10 seconds, rated the level of respiratory distress, and then examined the patient for vital signs and 17 other physical signs. We used the rating of distress as a surrogate for measuring the work of breathing, constructed three multivariate models to identify the one with the smallest number of signs and largest explained variance, and validated it with bootstrap analysis.We performed 402 observations on 240 patients. Respiratory distress was absent in 78, mild in 157, moderate in 107, and severe in 60. Respiratory rate, hypoxia, heart rate, and frequency of most signs increased as distress increased. Respiratory rate and hypoxia explained 43% of the variance in respiratory distress. Diaphoresis, gasping, and contraction of the sternomastoid explained an additional 28%. Heart rate, blood pressure, alertness, agitation, body posture, nasal flaring, audible breathing, cyanosis, tracheal tug, retractions, paradox, scalene or abdominal muscles contraction did not increase the explained variance in respiratory distress.Most of the variance is respiratory distress can be explained by five signs summarized by the mnemonic DiapHRaGM (diaphoresis, hypoxia, respiratory rate, gasping, accessory muscle. This set of signs may allow for efficient, standardized assessments of the work of breathing of hypoxic patients.

Decreased Respiratory Muscle Function Is Associated with Impaired Trunk Balance among Chronic Stroke Patients: A Cross-sectional Study.

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Lee, Kyeongbong; Cho, Ji-Eun; Hwang, Dal-Yeon; Lee, WanHee

2018-06-01

The abdominal muscles play a role in trunk balance. Abdominal muscle thickness is asymmetrical in stroke survivors, who also have decreased respiratory muscle function. We compared the thickness of the abdominal muscles between the affected and less affected sides in stroke survivors. In addition, the relationship between respiratory muscle function and trunk balance was evaluated. Chronic stroke patients (18 men, 15 women; mean age, 58.94 ± 12.30 years; Mini-Mental Status Examination score ≥ 24) who could sit without assist were enrolled. Abdominal muscle thickness during rest and contraction was measured with ultrasonography, and the thickening ratio was calculated. Respiratory muscle function assessment included maximum respiratory pressure, peak flow, and air volume. Trunk function was evaluated using the Trunk Impairment Scale, and trunk balance was estimated based on the center of pressure velocity and path length within the limit of stability in sitting posture. Abdominal muscles were significantly thinner on the affected side, and the thickening ratio was lower in the affected side (P respiratory muscle function was significantly correlated with higher level of trunk function and balance in stroke patients (P respiratory muscle function has positive correlation with trunk function and balance. We propose that respiratory muscle training should be included as part of trunk balance training in chronic stroke patients.

Assessment of breathing patterns and respiratory muscle recruitment during singing and speech in quadriplegia.

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Tamplin, Jeanette; Brazzale, Danny J; Pretto, Jeffrey J; Ruehland, Warren R; Buttifant, Mary; Brown, Douglas J; Berlowitz, David J

2011-02-01

To explore how respiratory impairment after cervical spinal cord injury affects vocal function, and to explore muscle recruitment strategies used during vocal tasks after quadriplegia. It was hypothesized that to achieve the increased respiratory support required for singing and loud speech, people with quadriplegia use different patterns of muscle recruitment and control strategies compared with control subjects without spinal cord injury. Matched, parallel-group design. Large university-affiliated public hospital. Consenting participants with motor-complete C5-7 quadriplegia (n=6) and able-bodied age-matched controls (n=6) were assessed on physiologic and voice measures during vocal tasks. Not applicable. Standard respiratory function testing, surface electromyographic activity from accessory respiratory muscles, sound pressure levels during vocal tasks, the Voice Handicap Index, and the Perceptual Voice Profile. The group with quadriplegia had a reduced lung capacity (vital capacity, 71% vs 102% of predicted; P=.028), more perceived voice problems (Voice Handicap Index score, 22.5 vs 6.5; P=.046), and greater recruitment of accessory respiratory muscles during both loud and soft volumes (P=.028) than the able-bodied controls. The group with quadriplegia also demonstrated higher accessory muscle activation in changing from soft to loud speech (P=.028). People with quadriplegia have impaired vocal ability and use different muscle recruitment strategies during speech than the able-bodied. These findings will enable us to target specific measurements of respiratory physiology for assessing functional improvements in response to formal therapeutic singing training. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Respiratory muscle training with enzyme replacement therapy improves muscle strength in late - onset Pompe disease.

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Jevnikar, Mitja; Kodric, Metka; Cantarutti, Fabiana; Cifaldi, Rossella; Longo, Cinzia; Della Porta, Rossana; Bembi, Bruno; Confalonieri, Marco

2015-12-01

Pompe disease is an autosomal recessive metabolic disorder caused by the deficiency of the lysosomal enzyme acid α-glucosidase. This deficiency leads to glycogen accumulation in the lysosomes of muscle tissue causing progressive muscular weakness particularly of the respiratory system. Enzyme replacement therapy (ERT) has demonstrated efficacy in slowing down disease progression in infants. Despite the large number of studies describing the effects of physical training in juvenile and adult late onset Pompe disease (LOPD). There are very few reports that analyze the benefits of respiratory muscle rehabilitation or training. The effectiveness of respiratory muscle training was investigated using a specific appliance with adjustable resistance (Threshold). The primary endpoint was effect on respiratory muscular strength by measurements of MIP and MEP. Eight late-onset Pompe patients (aged 13 to 58 years; 4 female, 4 male) with respiratory muscle deficiency on functional respiratory tests were studied. All patients received ERT at the dosage of 20 mg/kg/every 2 weeks and underwent training with Threshold at specified pressures for 24 months. A significant increase in MIP was observed during the follow-up of 24 month: 39.6 cm H 2 O (+ 25.0%) at month 3; 39.5 cm H 2 O (+ 24.9%) at month 6; 39.1 cm H 2 O (+ 23.7%) at month 9; 37.3 cm H 2 O (+ 18.2%) at month 12; and 37.3 cm H 2 O (+ 17.8%) at month 24. Median MEP values also showed a significant increase during the first 9 months: 29.8 cm H 2 O, (+ 14.3%) at month 3; 31.0 cm H 2 O (+ 18.6) at month 6; and 29.5 cm H 2 O (+ 12.9) at month 9. MEP was then shown to be decreased at months 12 and 24; median MEP was 27.2 cm H 2 O (+ 4.3%) at 12 months and 26.6 cm H 2 O (+ 1.9%) at 24 months. The FVC remain stable throughout the study. An increase in respiratory muscular strength was demonstrated with Threshold training when used in combination with ERT.

The Effect of Renal Transplantation on Respiratory Muscle Strength in Patients with End Stage Renal Disease

OpenAIRE

Tavana, Sasan; Mirzaei, Samaneh

2016-01-01

Background: There is evidence of musculoskeletal and respiratory involvement in patients with chronic kidney disease (CKD). This is attributed to protein calorie imbalance that is caused by the disease process, and hemodialysis and is generally referred to as uremic myopathy. This results in calcification of respiratory muscles such as diaphragm and intercostal muscles. There are limited data about respiratory muscle strength in patients with CKD. We intended to evaluate the effect of kidney ...

Respiratory muscle decline in Duchenne muscular dystrophy.

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Khirani, Sonia; Ramirez, Adriana; Aubertin, Guillaume; Boulé, Michèle; Chemouny, Chrystelle; Forin, Véronique; Fauroux, Brigitte

2014-05-01

Duchenne muscular dystrophy (DMD) causes progressive respiratory muscle weakness. The aim of the study was to analyze the trend of a large number of respiratory parameters to gain further information on the course of the disease. Retrospective study. 48 boys with DMD, age range between 6 and 19 year old, who were followed in our multidisciplinary neuromuscular clinic between 2001 and 2011. Lung function, blood gases, respiratory mechanics, and muscle strength were measured during routine follow-up over a 10-year period. Only data from patients with at least two measurements were retained. The data of 28 patients were considered for analysis. Four parameters showed an important decline with age. Gastric pressure during cough (Pgas cough) was below normal in all patients with a mean decline of 5.7 ± 3.8 cmH2 O/year. Sniff nasal inspiratory pressure (SNIP) tended to increase first followed by a rapid decline (mean decrease 4.8 ± 4.9 cmH2 O; 5.2 ± 4.4% predicted/year). Absolute forced vital capacity (FVC) values peaked around the age of 13-14 years and remained mainly over 1 L but predicted values showed a mean 4.1 ± 4.4% decline/year. Diaphragmatic tension-time index (TTdi) increased above normal values after the age of 14 years with a mean increase of 0.04 ± 0.04 point/year. This study confirms the previous findings that FVC and SNIP are among the most important parameters to monitor the evolution of DMD. Expiratory muscle strength, assessed by Pgas cough, and the endurance index, TTdi, which are reported for the first time in a large cohort, appeared to be informative too, even though measured through an invasive method. © 2013 Wiley Periodicals, Inc.

F-18 FDG uptake in respiratory muscle mimicking metastasis in patients with gastric cancer

International Nuclear Information System (INIS)

Choi, Seung Jin; Hyun, In Young; Kim, Jeong Ho

2006-01-01

A 67-year-old man with a history of chronic obstructive pulmonary disease (COPD) underwent F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for staging of gastric cancer. The projection images of F-18 FDG PET/CT showed intensely increased F-18 FDG uptake in the anterior neck, chest wall, and upper abdomen. We suspected distant metastases of cervical lymph nodes, ribs, and peritoneum in gastric cancer. However, the transaxial images of F-18 FDG PET/CT showed abnormal F-18 FDG uptake in scalene muscles of anterior neck, intercostal muscles of chest wall, and diaphragm of upper abdomen. Patients with COPD use respiratory muscles extensively on the resting condition. These excessive physiologic use of respiratory muscles causes increased F-18 FDG uptake as a result of increased glucose metabolism. The F-18 FDG uptake in respiratory muscles of gastric cancer patient with COPD mimicked distant metastases in cervical lymph nodes, ribs, and peritoneum

[Electromyographic determination of the fatigability of respiratory and leg muscles before and after aortocoronary bypass operation].

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Worth, H; Grundmann, C; Goeckenjan, G; Smidt, U; Irlich, G; Loogen, F

1984-01-01

To study the effect of postoperative confinement to bed on respiratory muscle fatigue, 31 male subjects (age, 34-66 years) undergoing coronary artery revascularization were examined. Fatigue of both respiratory muscles (musculi intercostales externi) and leg muscles (musculus gastrocnemius) was determined by electromyography prior to and 7 and 12 days after operation. Additionally, oscillatory resistance to breathing and phase angle were measured. Pre- and postoperative routine lung function tests were performed. A comparison between preoperative and postoperative measurements reveals that respiratory as well as leg muscle fatigue occurred at higher loads during the preoperative and the second postoperative than during the first postoperative determination. After surgery vital capacity, total lung capacity, 1-second capacity, and, to a lower extent, thoracic gas volume were diminished, while specific airway conductance, oscillatory resistance to breathing, phase angle, residual volume, and relative 1-second capacity remained unchanged. The constancy of the latter parameters indicates that neither airway obstruction nor a significant restriction of the lung and/or thorax occurred due to surgery. Therefore, the increase of respiratory muscle fatigue after surgery may more probably be attributed to a lack of training of respiratory muscles which may contribute to limitation of ventilation in bedridden patients.

Evaluation of Respiratory Muscles Activity by means of Cross Mutual Information Function at Different Levels of Ventilatory Effort

OpenAIRE

Alonso López, Joan Francesc; Mañanas Villanueva, Miguel Ángel; Hoyer, Dirk; Bruce, Eugene N.; Zbigniew L., Topor

2007-01-01

Analysis of respiratory muscles activity is an effective technique for the study of pulmonary diseases such as obstructive sleep apnea syndrome (OSAS). Respiratory diseases, especially those associated with changes in the mechanical properties of the respiratory apparatus, are often associated with disruptions of the normally highly coordinated contractions of respiratory muscles. Due to the complexity of the respiratory control, the assessment of OSAS related dysfunctions by linear ...

Respiratory muscle endurance is limited by lower ventilatory efficiency in post-myocardial infarction patients

OpenAIRE

Neves,Laura M. T.; Karsten,Marlus; Neves,Victor R.; Beltrame,Thomas; Borghi-Silva,Audrey; Catai,Aparecida M.

2014-01-01

Background: Reduced respiratory muscle endurance (RME) contributes to increased dyspnea upon exertion in patients with cardiovascular disease. Objective: The objective was to characterize ventilatory and metabolic responses during RME tests in post-myocardial infarction patients without respiratory muscle weakness. Method: Twenty-nine subjects were allocated into three groups: recent myocardial infarction group (RG, n=9), less-recent myocardial infarction group (LRG, n=10), and contr...

Acute exercise induces biphasic increase in respiratory mRNA in skeletal muscle

International Nuclear Information System (INIS)

Ikeda, Shin-ichi; Kizaki, Takako; Haga, Shukoh; Ohno, Hideki; Takemasa, Tohru

2008-01-01

Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) promotes the expression of oxidative enzymes in skeletal muscle. We hypothesized that activation of the p38 MAPK (mitogen-activated protein kinase) in response to exercise was associated with exercise-induced PGC-1α and respiratory enzymes expression and aimed to demonstrate this under the physiological level. We subjected mice to a single bout of treadmill running and found that the exercise induced a biphasic increase in the expression of respiratory enzymes mRNA. The second phase of the increase was accompanied by an increase in PGC-1α protein, but the other was not. Administration of SB203580 (SB), an inhibitor of p38 MAPK, suppressed the increase in PGC-1α expression and respiratory enzymes mRNA in both phases. These data suggest that p38 MAPK is associated with the exercise-induced expression of PGC-1α and biphasic increase in respiratory enzyme mRNAs in mouse skeletal muscle under physiological conditions

Contribution of Respiratory Muscle Oxygen Consumption to Breathing Limitation and Cyspnea

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Pere Casan

1997-01-01

Full Text Available During exercise, the sustainable activity of large muscle groups is limited by oxygen delivery. The purpose of this study was to see whether the oxygen consumption of the respiratory muscles reaches a similar critical value under maximal resistive loading and hyperventilation. A secondary objective was to see whether dyspnea (estimated discomfort experienced with breathing using the Borg 0-10 scale and the oxygen consumption of the respiratory muscles are closely related across conditions. This would be expected if intramuscular sensory nerve fibres stimulated as a consequence of metabolic events contributed to this sensation. In six normal subjects the respiratory muscles were progressively activated by the addition of incremental inspiratory resistive loads to a maximum of 300 cm H20×s/L (SD=66.4, and incremental dead space to a maximum of 2638 mL (SD=452, associated with an increase in ventilation to 75.1 L/min (SD=29.79. Each increment was maintained for 5 mins to allow the measurement of oxygen uptake in a steady state. During resistive loading total oxygen consumption increased from 239 mL/min (SD=38.2 to 299 mL/min (SD=52.3 and dyspnea increased to "very severe" (Borg scale 7.5, SD=1.55. During dead space loading total oxygen consumption increased from 270 mL/min (SD=20.2 to 426 mL/min (SD=81.9 and dyspnea increased to "very severe" (7.1, SD=0.66. Oxygen cost of inspiratory muscle power was 25 mL/watt (95% confidence limits 16.7 to 34.3 with dead space loading and 91 mL/watt (95% confidence limits 54 to 128 with resistive loading. Oxygen consumption did not reach a critical common value in the two types of loading, 60 mL/min (SD 22.3 during maximal resistive loading and 156 mL/min (SD 82.4 during maximal dead space loading (P<0.05. Physiological factors limiting the respiratory muscles are not uniquely related to oxygen consumption and appear to be expressed through the activation of sensory structures, perceptually manifested as

Effects of respiratory muscle endurance training on wheelchair racing performance in athletes with paraplegia: a pilot study.

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Muller, G.; Perret, C.; Hopman, M.T.E.

2008-01-01

OBJECTIVE: Respiratory muscle endurance training (RMET) has been shown to improve both respiratory muscle and cycling exercise endurance in able-bodied subjects. Since effects of RMET on upper extremity exercise performance have not yet been investigated, we evaluated the effects of RMET on 10-km

Does treadmill running performance, heart rate and breathing rate response during maximal graded exercise improve after volitional respiratory muscle training?

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Radhakrishnan, K; Sharma, V K; Subramanian, S K

2017-05-10

Maximal physical exertion in sports usually causes fatigue in the exercising muscles, but not in the respiratory muscles due to triggering of the Respiratory muscle metabo-reflex, a sympathetic vasoconstrictor response leading to preferential increment in blood flow to respiratory muscles. 1 We planned to investigate whether a six week yogic pranayama based Volitional Respiratory Muscle Training (VRMT) can improve maximal Graded Exercise Treadmill Test (GXTT) performance in healthy adult recreational sportspersons. Consecutive, consenting healthy adult recreational sportspersons aged 20.56±2.49 years (n=30), volunteered to 'baseline recording' of resting heart rate (HR), blood pressure (BP), respiratory rate (RR), and Bruce ramp protocol maximal GXTT until volitional exhaustion providing total test time (TTT), derived VO2max, Metabolic Equivalent of Task (METs), HR and BP response during maximal GXTT and drop in recovery HR data. After six weeks of observation, they underwent 'pre-intervention recording' followed by supervised VRMT intervention for 6 weeks (30 minutes a day; 5 days a week) and then 'post-intervention recording'. Repeated measures ANOVA with pairwise t statistical comparison was used to analyse the data. After supervised VRMT, we observed significant decrease in their resting supine RR (prespiratory muscle aerobic capacity, attenuation of respiratory muscle metabo-reflex, increase in cardiac stroke volume and autonomic resetting towards parasympatho-dominance. Yogic Pranayama based VRMT can be used in sports conditioning programme of athletes to further improve their maximal exercise performance, and as part of rehabilitation training during return from injury.

Does respiratory muscle training increase physical performance?

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Sperlich, Billy; Fricke, Hannes; de Marées, Markus; Linville, John W; Mester, Joachim

2009-09-01

Special force units and military personnel undergo demanding physical exercise and might benefit from high-intensity respiratory muscle training (RMT) by increasing their endurance performance. This study examined the effects of a 6-week high-intensity RMT on running performance and oxygen uptake (VO2max) in a group of German Special Force Squad members. 17 participants were randomly assigned to a training or control group. Baseline and post-testing included a ramp test, as well as an incremental test on a treadmill, performed to physical exhaustion. VO2, respiratory exchange ratio, and heart rate were measured breath by breath. Furthermore, maximum running speed (V(max)), 4 mmol x 1(-1) lactate threshold (V4) and perception of respiratory effort were determined. During pulmonary testing, sustained maximum inspiratory and expiratory pressure (PI(max) and PE(max)) were obtained. RMT was performed daily at approximately 90% PI(max) for 6 weeks with 2 x 30 breath cycles using an Ultrabreathe lung trainer. No statistical differences were detected between the groups for any parameter after RMT. High-intensity RMT did not show any benefits on VO2max and endurance performance and are unlikely to be of benefit to military or paramilitary training programs for an increase in endurance performance.

Sildenafil reduces respiratory muscle weakness and fibrosis in the mdx mouse model of Duchenne muscular dystrophy.

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Percival, Justin M; Whitehead, Nicholas P; Adams, Marvin E; Adamo, Candace M; Beavo, Joseph A; Froehner, Stanley C

2012-09-01

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy caused by mutations in the dystrophin gene. Loss of dystrophin initiates a progressive decline in skeletal muscle integrity and contractile capacity which weakens respiratory muscles including the diaphragm, culminating in respiratory failure, the leading cause of morbidity and mortality in DMD patients. At present, corticosteroid treatment is the primary pharmacological intervention in DMD, but has limited efficacy and adverse side effects. Thus, there is an urgent need for new safe, cost-effective, and rapidly implementable treatments that slow disease progression. One promising new approach is the amplification of nitric oxide-cyclic guanosine monophosphate (NO-cGMP) signalling pathways with phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors serve to amplify NO signalling that is attenuated in many neuromuscular diseases including DMD. We report here that a 14-week treatment of the mdx mouse model of DMD with the PDE5 inhibitor sildenafil (Viagra(®), Revatio(®)) significantly reduced mdx diaphragm muscle weakness without impacting fatigue resistance. In addition to enhancing respiratory muscle contractility, sildenafil also promoted normal extracellular matrix organization. PDE5 inhibition slowed the establishment of mdx diaphragm fibrosis and reduced matrix metalloproteinase-13 (MMP-13) expression. Sildenafil also normalized the expression of the pro-fibrotic (and pro-inflammatory) cytokine tumour necrosis factor α (TNFα). Sildenafil-treated mdx diaphragms accumulated significantly less Evans Blue tracer dye than untreated controls, which is also indicative of improved diaphragm muscle health. We conclude that sildenafil-mediated PDE5 inhibition significantly reduces diaphragm respiratory muscle dysfunction and pathology in the mdx mouse model of Duchenne muscular dystrophy. This study provides new insights into the therapeutic utility of targeting defects in NO

Six-minute walk test and respiratory muscle strength in patients with uncontrolled severe asthma: a pilot study.

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Pereira, Luiz Fernando Ferreira; Mancuzo, Eliane Viana; Rezende, Camila Farnese; Côrrea, Ricardo de Amorim

2015-01-01

To evaluate respiratory muscle strength and six-minute walk test (6MWT) variables in patients with uncontrolled severe asthma (UCSA). This was a cross-sectional study involving UCSA patients followed at a university hospital. The patients underwent 6MWT, spirometry, and measurements of respiratory muscle strength, as well as completing the Asthma Control Test (ACT). The Mann-Whitney test was used in order to analyze 6MWT variables, whereas the Kruskal-Wallis test was used to determine whether there was an association between the use of oral corticosteroids and respiratory muscle strength. We included 25 patients. Mean FEV1 was 58.8 ± 21.8% of predicted, and mean ACT score was 14.0 ± 3.9 points. No significant difference was found between the median six-minute walk distance recorded for the UCSA patients and that predicted for healthy Brazilians (512 m and 534 m, respectively; p = 0.14). During the 6MWT, there was no significant drop in SpO2. Mean MIP and MEP were normal (72.9 ± 15.2% and 67.6 ± 22.2%, respectively). Comparing the patients treated with at least four courses of oral corticosteroids per year and those treated with three or fewer, we found no significant differences in MIP (p = 0.15) or MEP (p = 0.45). Our findings suggest that UCSA patients are similar to normal subjects in terms of 6MWT variables and respiratory muscle strength. The use of oral corticosteroids has no apparent impact on respiratory muscle strength.

Reduction of cervical and respiratory muscle strength in patients with chronic nonspecific neck pain and having moderate to severe disability.

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López-de-Uralde-Villanueva, Ibai; Sollano-Vallez, Ernesto; Del Corral, Tamara

2017-06-11

To investigate whether patients with chronic nonspecific neck pain and having moderate to severe disability have a greater cervical motor function impairment and respiratory disturbances compared with patients with chronic nonspecific neck pain having mild disability and asymptomatic subjects; and the association between these outcomes in patients with chronic nonspecific neck pain and healthy controls. Cross-sectional study, 44 patients with chronic nonspecific neck pain and 31 healthy subjects participated. The neck disability index was used to divide the patients into 2 groups: 1) mild disability group (scores between 5 and 14 points); and 2) moderate to severe disability group (scores >14 points). Cervical motor function was measured by cervical range of motion, forward head posture, neck flexor, and extensor muscle strength. Respiratory function and maximum respiratory pressures were also measured. Statistically differences were found between the patients with chronic nonspecific neck pain having a moderate to severe disability and the asymptomatic subjects for cervical and respiratory muscle strength. Comparisons between chronic nonspecific neck pain and the asymptomatic groups showed differences for all the variables, except for forward head posture. The regression model determined that strength of cervical flexion explained 36.4 and 45.6% of the variance of maximum inspiratory pressures and maximum expiratory pressures, respectively. Only the chronic nonspecific neck pain group with moderate to severe disability showed differences compared with the healthy subjects. Neck muscle strength could be a good predictor of respiratory muscle function. Implications for rehabilitation Neck pain severity could be closely associated with decreased respiratory pressure in patients with chronic nonspecific neck pain. These findings suggest a new therapeutic approach for patients with moderate to severe disability, such as respiratory muscle training. The regression

The Gross Morphology and Histochemistry of Respiratory Muscles in Bottlenose Dolphins, Tursiops truncatus

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Cotten, Pamela B.; Piscitelli, Marina A.; McLellan, William A.; Rommel, Sentiel A.; Dearolf, Jennifer L.; Pabst, D. Ann

2011-01-01

Most mammals possess stamina because their locomotor and respiratory (i.e., ventilatory) systems are mechanically coupled. These systems are decoupled, however, in bottlenose dolphins (Tursiops truncatus) as they swim on a breath-hold. Locomotion and ventilation are coupled only during their brief surfacing event, when they respire explosively (up to 90% of total lung volume in approximately 0.3s) (Ridgway et al., 1969). The predominantly slow-twitch fiber profile of their diaphragm (Dearolf, 2003) suggests that this muscle does not likely power their rapid ventilatory event. Based upon Bramble's (1989) biomechanical model of locomotor-respiratory coupling in galloping mammals, it was hypothesized that locomotor muscles function to power ventilation in bottlenose dolphins. It was further hypothesized that these muscles would be composed predominantly of fast-twitch fibers to facilitate the bottlenose dolphin's rapid ventilation. The gross morphology of cranio-cervical (scalenus, sternocephalicus, sternohyoid), thoracic (intercostals, transverse thoracis), and lumbo-pelvic (hypaxialis, rectus abdominis, abdominal obliques) muscles (n=7) and the fiber-type profiles (n=6) of selected muscles (scalenus, sternocephalicus, sternohyoid, rectus abdominis) of bottlenose dolphins were investigated. Physical manipulations of excised thoracic units were carried out to investigate potential actions of these muscles. Results suggest that the cranio-cervical muscles act to draw the sternum and associated ribs cranio-dorsally, which flares the ribs laterally, and increases the thoracic cavity volume required for inspiration. The lumbo-pelvic muscles act to draw the sternum and caudal ribs caudally, which decreases the volumes of the thoracic and abdominal cavities required for expiration. All muscles investigated were composed predominantly of fast-twitch fibers (range 61-88% by area) and appear histochemically poised for rapid contraction. These combined results suggest that

Aspiration pneumonia induces muscle atrophy in the respiratory, skeletal, and swallowing systems.

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Komatsu, Riyo; Okazaki, Tatsuma; Ebihara, Satoru; Kobayashi, Makoto; Tsukita, Yoko; Nihei, Mayumi; Sugiura, Hisatoshi; Niu, Kaijun; Ebihara, Takae; Ichinose, Masakazu

2018-05-22

Repetition of the onset of aspiration pneumonia in aged patients is common and causes chronic inflammation. The inflammation induces proinflammatory cytokine production and atrophy in the muscles. The proinflammatory cytokines induce muscle proteolysis by activating calpains and caspase-3, followed by further degradation by the ubiquitin-proteasome system. Autophagy is another pathway of muscle atrophy. However, little is known about the relationship between aspiration pneumonia and muscle. For swallowing muscles, it is not clear whether they produce cytokines. The main objective of this study was to determine whether aspiration pneumonia induces muscle atrophy in the respiratory (the diaphragm), skeletal (the tibialis anterior, TA), and swallowing (the tongue) systems, and their possible mechanisms. We employed a mouse aspiration pneumonia model and computed tomography (CT) scans of aged pneumonia patients. To induce aspiration pneumonia, mice were inoculated with low dose pepsin and lipopolysaccharide solution intra-nasally 5 days a week. The diaphragm, TA, and tongue were isolated, and total RNA, proteins, and frozen sections were stored. Quantitative real-time polymerase chain reaction determined the expression levels of proinflammatory cytokines, muscle E3 ubiquitin ligases, and autophagy related genes. Western blot analysis determined the activation of the muscle proteolysis pathway. Frozen sections determined the presence of muscle atrophy. CT scans were used to evaluate the muscle atrophy in aged aspiration pneumonia patients. The aspiration challenge enhanced the expression levels of proinflammatory cytokines in the diaphragm, TA, and tongue. Among muscle proteolysis pathways, the aspiration challenge activated caspase-3 in all the three muscles examined, whereas calpains were activated in the diaphragm and the TA but not in the tongue. Activation of the ubiquitin-proteasome system was detected in all the three muscles examined. The aspiration challenge

Severe Chronic Obstructive Pulmonary Disease : assessment of respiratory muscle activity and the benefits of noninvasive ventilation

NARCIS (Netherlands)

Duiverman, Marieke Leontine

2008-01-01

This thesis deals with two main topics. First, we investigated respiratory muscle function in Chronic Obstructive Pulmonary Disease (COPD) by surface electromyography. Second, we focused on the benefits of noninvasive ventilation in patients with respiratory failure, both in restrictive pulmonary

Effect of upper extremity proprioceptive neuromuscular facilitation combined with elastic resistance bands on respiratory muscle strength: a randomized controlled trial

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Guilherme P. T. Areas

2013-12-01

Full Text Available BACKGROUND: Elastic resistance bands (ERB combined with proprioceptive neuromuscular facilitation (PNF are often used in resistance muscle training programs, which have potential effects on peripheral muscle strength. However, the effects of the combination of ERB and PNF on respiratory muscle strength warrant further investigation. OBJECTIVES: The assessment of the effects of PNF combined with ERB on respiratory muscle strength. METHOD: Twenty healthy, right-handed females were included. Subjects were randomized to either the resistance training program group (TG, n=10 or the control group (CG, n=10. Maximal expiratory pressure (MEP and inspiratory pressure (MIP were measured before and after four weeks of an upper extremity resistance training program. The training protocol consisted of upper extremity PNF combined with ERB, with resistance selected from 1 repetition maximum protocol. RESULTS: PNF combined with ERB showed significant increases in MIP and MEP (p<0.05. In addition, there were significant differences between the TG and CG regarding ∆MIP (p=0.01 and ∆MEP (p=0.04. CONCLUSIONS: PNF combined with ERB can have a positive impact on respiratory muscle strength. These results may be useful with respect to cardiopulmonary chronic diseases that are associated with reduced respiratory muscle strength.

Relationship between PPARα mRNA expression and mitochondrial respiratory function and ultrastructure of the skeletal muscle of patients with COPD.

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Zhang, Jian-Qing; Long, Xiang-Yu; Xie, Yu; Zhao, Zhi-Huan; Fang, Li-Zhou; Liu, Ling; Fu, Wei-Ping; Shu, Jing-Kui; Wu, Jiang-Hai; Dai, Lu-Ming

2017-11-02

Peripheral muscle dysfunction is an important complication in patients with chronic obstructive pulmonary disease (COPD). The objective of this study was to explore the relationship between the levels of peroxisome proliferator-activated receptor α (PPARα) mRNA expression and the respiratory function and ultrastructure of mitochondria in the vastus lateralis of patients with COPD. Vastus lateralis biopsies were performed on 14 patients with COPD and 6 control subjects with normal lung function. PPARα mRNA levels in the muscle tissue were detected by real-time PCR. A Clark oxygen electrode was used to assess mitochondrial respiratory function. Mitochondrial number, fractional area in skeletal muscle cross-sections, and Z-line width were observed via transmission electron microscopy. The PPARα mRNA expression was significantly lower in COPD patients with low body mass index (BMIL) than in both COPD patients with normal body mass index (BMIN) and controls. Mitochondrial respiratory function (assessed by respiratory control ratio) was impaired in COPD patients, particularly in BMIL. Compared with that in the control group, mitochondrial number and fractional area were lower in the BMIL group, but were maintained in the BMIN group. Further, the Z-line became narrow in the BMIL group. PPARα mRNA expression was positively related to mitochondrial respiratory function and volume density. In COPD patients with BMIN, mitochondria volume density was maintained, while respiratory function decreased, whereas both volume density and respiratory function decreased in COPD patients with BMIL. PPARα mRNA expression levels are associated with decreased mitochondrial respiratory function and volume density, which may contribute to muscle dysfunction in COPD patients.

Physical fitness and mitochondrial respiratory capacity in horse skeletal muscle.

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Dominique-Marie Votion

Full Text Available BACKGROUND: Within the animal kingdom, horses are among the most powerful aerobic athletic mammals. Determination of muscle respiratory capacity and control improves our knowledge of mitochondrial physiology in horses and high aerobic performance in general. METHODOLOGY/PRINCIPAL FINDINGS: We applied high-resolution respirometry and multiple substrate-uncoupler-inhibitor titration protocols to study mitochondrial physiology in small (1.0-2.5 mg permeabilized muscle fibres sampled from triceps brachii of healthy horses. Oxidative phosphorylation (OXPHOS capacity (pmol O(2 • s(-1 • mg(-1 wet weight with combined Complex I and II (CI+II substrate supply (malate+glutamate+succinate increased from 77 ± 18 in overweight horses to 103 ± 18, 122 ± 15, and 129 ± 12 in untrained, trained and competitive horses (N = 3, 8, 16, and 5, respectively. Similar to human muscle mitochondria, equine OXPHOS capacity was limited by the phosphorylation system to 0.85 ± 0.10 (N = 32 of electron transfer capacity, independent of fitness level. In 15 trained horses, OXPHOS capacity increased from 119 ± 12 to 134 ± 37 when pyruvate was included in the CI+II substrate cocktail. Relative to this maximum OXPHOS capacity, Complex I (CI-linked OXPHOS capacities were only 50% with glutamate+malate, 64% with pyruvate+malate, and 68% with pyruvate+malate+glutamate, and ~78% with CII-linked succinate+rotenone. OXPHOS capacity with glutamate+malate increased with fitness relative to CI+II-supported ETS capacity from a flux control ratio of 0.38 to 0.40, 0.41 and 0.46 in overweight to competitive horses, whereas the CII/CI+II substrate control ratio remained constant at 0.70. Therefore, the apparent deficit of the CI- over CII-linked pathway capacity was reduced with physical fitness. CONCLUSIONS/SIGNIFICANCE: The scope of mitochondrial density-dependent OXPHOS capacity and the density-independent (qualitative increase of CI-linked respiratory capacity with increased

Respiratory muscle stretch gymnastics in patients with post coronary artery bypass grafting pain: impact on respiratory muscle function, activity, mood and exercise capacity.

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Aida, Nobuko; Shibuya, Masako; Yoshino, Katsuki; Komoda, Masaji; Inoue, Tomoko

2002-12-01

A new rehabilitation (New-RH) program including respiratory muscle stretch gymnastics (RMSG) was developed to alleviate post-coronary artery bypass grafting pain (PCP). Effects on respiratory muscle function, pain, activities of daily living (ADL), mood and exercise capacity were investigated. Subjects were 16 consecutive patients undergoing median full sternotomy coronary artery bypass grafting (CABG), and were randomly divided into equal New-RH (S-group) and conventional therapy (C-group) groups. Rib cage dominant breathing was observed postoperatively in both groups. With preoperative tan deltaVrc/deltaVab, increases at 1-week postoperatively and decreases at discharge for S-group tended to exceed those of C-group (p > .05). Decreased maximum inspiratory and expiratory pressure status for functional residual capacity and percent forced expiratory volume in one second at discharge again only tended to be smaller for S-group (p > .05). S-group displayed significantly reduced pain around both scapulas at discharge (p = .049), and increased mean overall ADL and profile of mood states (POMS)/Vigor scores (p = .031 and p = .018, respectively). POMS/Tension-Anxiety scores at discharge for S-group were significantly smaller than those preoperatively (p = .025), and S-group displayed significantly increased distance walked over 6-minutes at discharge than C-group (p = .029). New-RH improves patient participation in exercise therapy and increases exercise capacity by reducing PCP, relieving anxiety and tension, and improving ADL.

Two weeks of one-leg immobilization decreases skeletal muscle respiratory capacity equally in young and elderly men

DEFF Research Database (Denmark)

Gram, Martin; Vigelsø Hansen, Andreas; Yokota, Takashi

2014-01-01

Physical inactivity affects human skeletal muscle mitochondrial oxidative capacity but the influence of aging combined with physical inactivity is not known. This study investigates the effect of two weeks of immobilization followed by six weeks of supervised cycle training on muscle oxidative...... capacity in 17 young (23±1years) and 15 elderly (68±1years) healthy men. We applied high-resolution respirometry in permeabilized fibers from muscle biopsies at inclusion after immobilization and training. Furthermore, protein content of mitochondrial complexes I-V, mitochondrial heat shock protein 70 (mt......HSP70) and voltage dependent anion channel (VDAC) were measured in skeletal muscle by Western blotting. The elderly men had lower content of complexes I-V and mtHSP70 but similar respiratory capacity and content of VDAC compared to the young. In both groups the respiratory capacity and protein content...

Inhaled β-agonist therapy and respiratory muscle fatigue as under-recognised causes of lactic acidosis.

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Lau, Emily; Mazer, Jeffrey; Carino, Gerardo

2013-10-14

A 49-year-old man with chronic obstructive pulmonary disease (COPD) presented with significant tachypnoea, fevers, productive cough and increased work of breathing for the previous 4 days. Laboratory data showed elevated lactate of 3.2 mEq/L. Continuous inhaled ipratropium and albuterol nebuliser treatments were administered. Lactate levels increased to 5.5 and 3.9 mEq/L, at 6 and 12 h, respectively. No infectious source was found and the lactic acidosis cleared as the patient improved. The lactic acidosis was determined to be secondary to respiratory muscle fatigue and inhaled β-agonist therapy, two under-recognised causes of lactic acidosis in patients presenting with respiratory distress. Lactic acidosis is commonly used as a clinical marker for sepsis and shock, but in the absence of tissue hypoperfusion and severe hypoxia, alternative aetiologies for elevated levels should be sought to avoid unnecessary and potentially harmful medical interventions.

Respiratory muscle endurance is limited by lower ventilatory efficiency in post-myocardial infarction patients

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Laura M. T. Neves

2014-03-01

Full Text Available Background: Reduced respiratory muscle endurance (RME contributes to increased dyspnea upon exertion in patients with cardiovascular disease. Objective: The objective was to characterize ventilatory and metabolic responses during RME tests in post-myocardial infarction patients without respiratory muscle weakness. Method: Twenty-nine subjects were allocated into three groups: recent myocardial infarction group (RG, n=9, less-recent myocardial infarction group (LRG, n=10, and control group (CG, n=10. They underwent two RME tests (incremental and constant pressure with ventilatory and metabolic analyses. One-way ANOVA and repeated measures one-way ANOVA, both with Tukey post-hoc, were used between groups and within subjects, respectively. Results: Patients from the RG and LRG presented lower metabolic equivalent and ventilatory efficiency than the CG on the second (50± 06, 50± 5 vs. 42± 4 and third part (50± 11, 51± 10 vs. 43± 3 of the constant pressure RME test and lower metabolic equivalent during the incremental pressure RME test. Additionally, at the peak of the incremental RME test, RG patients had lower oxygen uptake than the CG. Conclusions : Post-myocardial infarction patients present lower ventilatory efficiency during respiratory muscle endurance tests, which appears to explain their inferior performance in these tests even in the presence of lower pressure overload and lower metabolic equivalent.

Effects of aerobic training combined with respiratory muscle stretching on the functional exercise capacity and thoracoabdominal kinematics in patients with COPD: a randomized and controlled trial

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Wada JT

2016-10-01

Full Text Available Juliano T Wada,1 Erickson Borges-Santos,1 Desiderio Cano Porras,1 Denise M Paisani,1 Alberto Cukier,2 Adriana C Lunardi,1 Celso RF Carvalho1 1Department of Physical Therapy, 2Department of Cardiopneumology, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil Background: Patients with COPD present a major recruitment of the inspiratory muscles, predisposing to chest incoordination, increasing the degree of dyspnea and impairing their exercise capacity. Stretching techniques could decrease the respiratory muscle activity and improve their contractile capacity; however, the systemic effects of stretching remain unknown.Objective: The aim of this study was to evaluate the effects of aerobic training combined with respiratory muscle stretching on functional exercise capacity and thoracoabdominal kinematics in patients with COPD.Design: This study was a randomized and controlled trial.Participants: A total of 30 patients were allocated to a treatment group (TG or a control group (CG; n=15, each group.Intervention: The TG was engaged in respiratory muscle stretching and the CG in upper and lower limb muscle stretching. Both groups performed 24 sessions (twice a week, 12 weeks of aerobic training.Evaluations: Functional exercise capacity (6-minute walk test, thoracoabdominal kinematics (optoelectronic plethysmography, and respiratory muscle activity (surface electromyography were evaluated during exercise. Analysis of covariance was used to compare the groups at a significance level of 5%.Results: After the intervention, the TG showed improved abdominal (ABD contribution, compartmental volume, mobility, and functional exercise capacity with decreased dyspnea when compared with the CG (P<0.01. The TG also showed a decreased respiratory muscle effort required to obtain the same pulmonary volume compared to the CG (P<0.001.Conclusion: Our results suggest that aerobic training combined with respiratory muscle stretching increases the functional

High-resolution respirometry of fine-needle muscle biopsies in pre-manifest Huntington's disease expansion mutation carriers shows normal mitochondrial respiratory function.

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Eva Buck

Full Text Available Alterations in mitochondrial respiration are an important hallmark of Huntington's disease (HD, one of the most common monogenetic causes of neurodegeneration. The ubiquitous expression of the disease causing mutant huntingtin gene raises the prospect that mitochondrial respiratory deficits can be detected in skeletal muscle. While this tissue is readily accessible in humans, transgenic animal models offer the opportunity to cross-validate findings and allow for comparisons across organs, including the brain. The integrated respiratory chain function of the human vastus lateralis muscle was measured by high-resolution respirometry (HRR in freshly taken fine-needle biopsies from seven pre-manifest HD expansion mutation carriers and nine controls. The respiratory parameters were unaffected. For comparison skeletal muscle isolated from HD knock-in mice (HdhQ111 as well as a broader spectrum of tissues including cortex, liver and heart muscle were examined by HRR. Significant changes of mitochondrial respiration in the HdhQ knock-in mouse model were restricted to the liver and the cortex. Mitochondrial mass as quantified by mitochondrial DNA copy number and citrate synthase activity was stable in murine HD-model tissue compared to control. mRNA levels of key enzymes were determined to characterize mitochondrial metabolic pathways in HdhQ mice. We demonstrated the feasibility to perform high-resolution respirometry measurements from small human HD muscle biopsies. Furthermore, we conclude that alterations in respiratory parameters of pre-manifest human muscle biopsies are rather limited and mirrored by a similar absence of marked alterations in HdhQ skeletal muscle. In contrast, the HdhQ111 murine cortex and liver did show respiratory alterations highlighting the tissue specific nature of mutant huntingtin effects on respiration.

Effects of inspiratory muscle training on respiratory function and repetitive sprint performance in wheelchair basketball players.

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Goosey-Tolfrey, V; Foden, E; Perret, C; Degens, H

2010-07-01

There is considerable evidence that respiratory muscle training improves pulmonary function, quality of life and exercise performance in healthy athletic populations. The benefits for wheelchair athletes are less well understood. Therefore, in the present study, influence of inspiratory muscle training (IMT) on respiratory function and repetitive propulsive sprint performance in wheelchair basketball players was examined. Using a placebo-controlled design, 16 wheelchair athletes were divided to an experimental (IMT; n=8) or placebo (sham-IMT; n=8) group based on selective grouping criteria. 30 dynamic breaths were performed by the IMT group twice daily at a resistance equivalent to 50% maximum inspiratory pressure (MIP), and 60 slow breaths were performed by the sham-IMT group once a day at 15% MIP for a period of 6 weeks. In the IMT group, both MIP and maximum expiratory pressure (17% and 23%, respectively; ptraining device suggested "less breathlessness" and "less tightness in the chest during the training". Although there was no improvement in sprint performance, an improved respiratory muscle function and quality of life were reported by participants in both the IMT and sham-IMT groups.

The influence of respiratory acid-base changes on muscle performance and excitability of the sarcolemma during strenuous intermittent hand grip exercise.

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Hilbert, M; Shushakov, V; Maassen, N

2012-02-01

Acidification has been reported to provide protective effects on force production in vitro. Thus, in this study, we tested if respiratory acid-base changes influence muscle function and excitability in vivo. Nine subjects performed strenuous, intermittent hand grip exercises (10 cycles of 15 s of work/45 s of rest) under respiratory acidosis by CO(2) rebreathing, alkalosis by hyperventilation, or control. The Pco(2), pH, K(+) concentration ([K(+)]), and Na(+) concentration were measured in venous and arterialized blood. Compound action potentials (M-wave) were elicited to examine the excitability of the sarcolemma. The surface electromyogram (EMG) was recorded to estimate the central drive to the muscle. The lowest venous pH during the exercise period was 7.24 ± 0.03 in controls, 7.31 ± 0.05 with alkalosis, and 7.17 ± 0.04 with acidosis (P alkalosis, and, after the second cycle, it was smaller with acidosis than with the control condition (P Respiratory alkalosis stabilized the M-wave area without influencing performance. Thus, we did not find a direct link between performance and alteration of excitability of the sarcolemma due to changes in pH in vivo.

Aging augments the impact of influenza respiratory tract infection on mobility impairments, muscle-localized inflammation, and muscle atrophy.

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Bartley, Jenna M; Pan, Sarah J; Keilich, Spencer R; Hopkins, Jacob W; Al-Naggar, Iman M; Kuchel, George A; Haynes, Laura

2016-04-01

Although the influenza virus only infects the respiratory system, myalgias are commonly experienced during infection. In addition to a greater risk of hospitalization and death, older adults are more likely to develop disability following influenza infection; however, this relationship is understudied. We hypothesized that upon challenge with influenza, aging would be associated with functional impairments, as well as upregulation of skeletal muscle inflammatory and atrophy genes. Infected young and aged mice demonstrated decreased mobility and altered gait kinetics. These declines were more prominent in hind limbs and in aged mice. Skeletal muscle expression of genes involved in inflammation, as well as muscle atrophy and proteolysis, increased during influenza infection with an elevated and prolonged peak in aged mice. Infection also decreased expression of positive regulators of muscle mass and myogenesis components to a greater degree in aged mice. Gene expression correlated to influenza-induced body mass loss, although evidence did not support direct muscle infection. Overall, influenza leads to mobility impairments with induction of inflammatory and muscle degradation genes and downregulation of positive regulators of muscle. These effects are augmented and prolonged with aging, providing a molecular link between influenza infection, decreased resilience and increased risk of disability in the elderly.

Immediate effect of manual therapy on respiratory functions and inspiratory muscle strength in patients with COPD

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Yilmaz Yelvar GD

2016-06-01

Full Text Available Gul Deniz Yilmaz Yelvar,1 Yasemin Çirak,2 Yasemin Parlak Demir,3 Murat Dalkilinç,1 Bülent Bozkurt4 1Department of Musculoskeletal Physiotherapy, 2Department of Cardiopulmonary Physiotherapy, 3Department of Neurological Rehabilitation, School of Physiotherapy and Rehabilitation, 4Department of Respiratory Medicine, Faculty of Medicine, Turgut Özal University, Ankara, Turkey Objective: The objective of this study was to investigate the immediate effect of manual therapy (MT on respiratory functions and inspiratory muscle strength in patients with COPD.Participants and methods: Thirty patients with severe COPD (eight females and 22 males; mean age 62.4±6.8 years referred to pulmonary physiotherapy were included in this study. The patients participated in a single session of MT to measure the short-term effects. The lung function was measured using a portable spirometer. An electronic pressure transducer was used to measure respiratory muscle strength. Heart rate, breathing frequency, and oxygen saturation were measured with a pulse oximeter. For fatigue and dyspnea perception, the modified Borg rating of perceived exertion scale was used. All measurements were taken before and immediately after the first MT session. The ease-of-breathing visual analog scale was used for rating patients’ symptoms subjectively during the MT session.Results: There was a significant improvement in the forced expiratory volume in the first second, forced vital capacity, and vital capacity values (P<0.05. The maximal inspiratory pressure and maximal expiratory pressure values increased significantly after MT, compared to the pre-MT session (P<0.05. There was a significant decrease in heart rate, respiratory rate (P<0.05, and dyspnea and fatigue perception (P<0.05.Conclusion: A single MT session immediately improved pulmonary function, inspiratory muscle strength, and oxygen saturation and reduced dyspnea, fatigue, and heart and respiratory rates in patients with

Genetic deficiency of GABA differentially regulates respiratory and non-respiratory motor neuron development.

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Matthew J Fogarty

Full Text Available Central nervous system GABAergic and glycinergic synaptic activity switches from postsynaptic excitation to inhibition during the stage when motor neuron numbers are being reduced, and when synaptic connections are being established onto and by motor neurons. In mice this occurs between embryonic (E day 13 and birth (postnatal day 0. Our previous work on mice lacking glycinergic transmission suggested that altered motor neuron activity levels correspondingly regulated motor neuron survival and muscle innervation for all respiratory and non respiratory motor neuron pools, during this period of development [1]. To determine if GABAergic transmission plays a similar role, we quantified motor neuron number and the extent of muscle innervation in four distinct regions of the brain stem and spinal cord; hypoglossal, phrenic, brachial and lumbar motor pools, in mice lacking the enzyme GAD67. These mice display a 90% drop in CNS GABA levels ( [2]; this study. For respiratory-based motor neurons (hypoglossal and phrenic motor pools, we have observed significant drops in motor neuron number (17% decline for hypoglossal and 23% decline for phrenic and muscle innervations (55% decrease. By contrast for non-respiratory motor neurons of the brachial lateral motor column, we have observed an increase in motor neuron number (43% increase and muscle innervations (99% increase; however for more caudally located motor neurons within the lumbar lateral motor column, we observed no change in either neuron number or muscle innervation. These results show in mice lacking physiological levels of GABA, there are distinct regional changes in motor neuron number and muscle innervation, which appear to be linked to their physiological function and to their rostral-caudal position within the developing spinal cord. Our results also suggest that for more caudal (lumbar regions of the spinal cord, the effect of GABA is less influential on motor neuron development compared to

Voltage-dependent amplification of synaptic inputs in respiratory motoneurones

DEFF Research Database (Denmark)

Enríquez Denton, M; Wienecke, Jacob; Zhang, Mengliang

2012-01-01

time, the likely amplifying processes at work in respiratory motoneurones. In phrenic motoneurones, which control the most important respiratory muscle, the diaphragm, we found that the mechanism most favoured by investigations in other motoneurones, the activation of persistent inward currents via...

Effects of bedding systems selected by manual muscle testing on sleep and sleep-related respiratory disturbances.

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Tsai, Ling-Ling; Liu, Hau-Min

2008-03-01

In this study, we investigated the feasibility of applying manual muscle testing (MMT) for bedding selection and examined the bedding effect on sleep. Four lay testers with limited training in MMT performed muscle tests for the selection of the bedding systems from five different mattresses and eight different pillows for 14 participants with mild sleep-related respiratory disturbances. For each participant individually, two bedding systems-one inducing stronger muscle forces and the other inducing weaker forces-were selected. The tester-participant pairs showed 85% and 100% agreement, respectively, for the selection of mattresses and pillows that induced the strongest muscle forces. The firmness of the mattress and the height of the pillow were significantly correlated with the body weight and body mass index of the participants for the selected strong bedding system but not for the weak bedding system. Finally, differences were observed between the strong and the weak bedding systems with regard to sleep-related respiratory disturbances and the percentage of slow-wave sleep. It was concluded that MMT can be performed by inexperienced testers for the selection of bedding systems.

Effects of wheelchair sports on respiratory muscle strength and thoracic mobility of individuals with spinal cord injury.

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Moreno, Marlene Aparecida; Zamunér, Antonio Roberto; Paris, Juliana Viana; Teodori, Rosana Macher; Barros, Ricardo M L

2012-06-01

The aim of this study was to evaluate the effects of wheelchair sports on respiratory muscle strength and the thoracic mobility of individuals with spinal cord injury. Thirty male subjects with chronic spinal cord injury (American Spinal Injury Association Impairment Scale grade A) took part in the study and were divided into four groups: sedentary subjects with quadriplegia (S-QUAD, n = 7), wheelchair rugby athletes with quadriplegia (A-QUAD, n = 8), sedentary subjects with paraplegia (S-PARA, n = 6), and wheelchair basketball athletes with paraplegia (A-PARA, n = 9). The main outcome measures were maximal inspiratory and expiratory pressure and the respiratory coefficients at the axillary and xiphoid levels. A-QUAD group presented values significantly higher for all respiratory variables studied compared with the S-QUAD group. No significant differences in any of the respiratory variables were observed between S-PARA and A-PARA groups. There was a negative correlation between spinal cord injury level and respiratory variables for the S-QUAD and S-PARA groups. There were positive correlations in the A-QUAD group between time of training and maximal inspiratory pressure (adjusted R = 0.84; P = 0.001) and respiratory coefficients at the axillary level (adjusted R = 0.80; P = 0.002). Physical training seems to have a positive influence on respiratory muscle strength and thoracic mobility, especially in subjects with quadriplegia.

Effect of respiratory muscle training on exercise performance in healthy individuals: a systematic review and meta-analysis.

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Illi, Sabine K; Held, Ulrike; Frank, Irène; Spengler, Christina M

2012-08-01

Two distinct types of specific respiratory muscle training (RMT), i.e. respiratory muscle strength (resistive/threshold) and endurance (hyperpnoea) training, have been established to improve the endurance performance of healthy individuals. We performed a systematic review and meta-analysis in order to determine the factors that affect the change in endurance performance after RMT in healthy subjects. A computerized search was performed without language restriction in MEDLINE, EMBASE and CINAHL and references of original studies and reviews were searched for further relevant studies. RMT studies with healthy individuals assessing changes in endurance exercise performance by maximal tests (constant load, time trial, intermittent incremental, conventional [non-intermittent] incremental) were screened and abstracted by two independent investigators. A multiple linear regression model was used to identify effects of subjects' fitness, type of RMT (inspiratory or combined inspiratory/expiratory muscle strength training, respiratory muscle endurance training), type of exercise test, test duration and type of sport (rowing, running, swimming, cycling) on changes in performance after RMT. In addition, a meta-analysis was performed to determine the effect of RMT on endurance performance in those studies providing the necessary data. The multiple linear regression analysis including 46 original studies revealed that less fit subjects benefit more from RMT than highly trained athletes (6.0% per 10 mL · kg⁻¹ · min⁻¹ decrease in maximal oxygen uptake, 95% confidence interval [CI] 1.8, 10.2%; p = 0.005) and that improvements do not differ significantly between inspiratory muscle strength and respiratory muscle endurance training (p = 0.208), while combined inspiratory and expiratory muscle strength training seems to be superior in improving performance, although based on only 6 studies (+12.8% compared with inspiratory muscle strength training, 95% CI 3

Effects of respiratory alkalosis on human skeletal muscle metabolism at the onset of submaximal exercise.

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LeBlanc, P J; Parolin, M L; Jones, N L; Heigenhauser, G J F

2002-10-01

The purpose of this study was to examine the effects of respiratory alkalosis on human skeletal muscle metabolism at rest and during submaximal exercise. Subjects exercised on two occasions for 15 min at 55 % of their maximal oxygen uptake while either hyperventilating (R-Alk) or breathing normally (Con). Muscle biopsies were taken at rest and after 1 and 15 min of exercise. At rest, no effects on muscle metabolism were observed in response to R-Alk. In the first minute of exercise, there was a delayed activation of pyruvate dehydrogenase (PDH) in R-Alk compared with Con, resulting in a reduced rate of pyruvate oxidation. Also, glycogenolysis was higher in R-Alk compared with Con, which was attributed to a higher availability of the monoprotonated form of inorganic phosphate (P(i)), resulting in an elevated rate of pyruvate production. The mismatch between pyruvate production and its oxidation resulted in net lactate accumulation. These effects were not seen after 15 min of exercise, with no further differences in muscle metabolism between conditions. The results from the present study suggest that respiratory alkalosis may play an important role in lactate accumulation during the transition from rest to exercise in acute hypoxic conditions, but that other factors mediate lactate accumulation during steady-state exercise.

High-fat feeding inhibits exercise-induced increase in mitochondrial respiratory flux in skeletal muscle

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Skovbro, Mette; Boushel, Robert Christopher; Hansen, Christina Neigaard

2011-01-01

) and intramyocellular triacylglycerol content did not change with the intervention in either group. Indexes of mitochondrial density were similar across the groups and intervention. Mitochondrial respiratory rates, measured in permeabilized muscle fibers, showed a 31 ± 11 and 26 ± 9% exercise-induced increase (P

Increased intrinsic mitochondrial respiratory capacity in skeletal muscle from rats with streptozotocin-induced hyperglycemia

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Larsen, Steen; Scheede-Bergdahl, Celena; Whitesell, Thomas

2015-01-01

the groups when evaluating the more physiol. complex I and II linked OXPHOS capacity. These findings indicate that chronic hyperglycemia results in an elevated intrinsic mitochondrial respiratory capacity in both soleus and, at varying degree, plantaris muscle, findings that are consistent with human T1DM...

Effects of inspiratory muscle training on pulmonary function, respiratory muscle strength and functional capacity in patients with atrial fibrillation: a randomized controlled trial.

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Zeren, Melih; Demir, Rengin; Yigit, Zerrin; Gurses, Hulya N

2016-12-01

To investigate the effects of inspiratory muscle training on pulmonary function, respiratory muscle strength and functional capacity in patients with atrial fibrillation. Prospective randomized controlled single-blind study. Cardiology department of a university hospital. A total of 38 patients with permanent atrial fibrillation were randomly allocated to either a treatment group (n = 19; age 66.2 years (8.8)) or a control group (n = 19; age 67.1 years (6.4)). The training group received inspiratory muscle training at 30% of maximal inspiratory pressure for 15 minutes twice a day, 7 days a week, for 12 weeks alongside the standard medical treatment. The control group received standard medical treatment only. Spirometry, maximal inspiratory and expiratory pressures and 6-minute walking distance was measured at the beginning and end of the study. There was a significant increase in maximal inspiratory pressure (27.94 cmH 2 O (8.90)), maximal expiratory pressure (24.53 cmH 2 O (10.34)), forced vital capacity (10.29% (8.18) predicted), forced expiratory volume in one second (13.88% (13.42) predicted), forced expiratory flow 25%-75% (14.82% (12.44) predicted), peak expiratory flow (19.82% (15.62) predicted) and 6-minute walking distance (55.53 m (14.13)) in the training group (p  0.05). Inspiratory muscle training can improve pulmonary function, respiratory muscle strength and functional capacity in patients with atrial fibrillation. © The Author(s) 2016.

Analysis of respiratory mechanomyographic signals by means of the empirical mode decomposition

International Nuclear Information System (INIS)

Torres, A; Jane, R; Fiz, J A; Laciar, E; Galdiz, J B; Gea, J; Morera, J

2007-01-01

The study of the mechanomyographic (MMG) signals of respiratory muscles is a promising technique in order to evaluate the respiratory muscles effort. A critical point in MMG studies is the selection of the cut-off frequency in order to separate the low frequency (LF) component (basically due to gross movement of the muscle or of the body) and the high frequency (HF) component (related with the vibration of the muscle fibres during contraction). In this study, we propose to use the Empirical Mode Decomposition method in order to analyze the Intrinsic Mode Functions of MMG signals of the diaphragm muscle, acquired by means of a capacitive accelerometer applied on the costal wall. The method was tested on an animal model, with two incremental respiratory protocols performed by two non anesthetized mongrel dogs. The proposed EMD based method seems to be a useful tool to eliminate the low frequency component of MMG signals. The obtained correlation coefficients between respiratory and MMG parameters were higher than the ones obtained with a Wavelet multiresolution decomposition method utilized in a previous work

Respiratory Muscle Training and Cognitive Function Exercising at Altitude.

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Quackenbush, Joseph; Duquin, Aubrey; Helfer, Samuel; Pendergast, David R

2016-01-01

Hiking and trekking often occur at altitudes up to 12,000 ft altitude. The hypoxia-induced hyperventilation at altitude paradoxically reduces arterial CO2 (Paco2). A reduction in Paco2 results in vasoconstriction of the blood vessels of the brain and thus in local hypoxia. The local hypoxia likely affects cognitive function, which may result in reduced performance and altitude accidents. Recent publications have demonstrated that voluntary isocapnic hyperventilatory training of the respiratory muscles (VIHT) can markedly enhance exercise endurance as it is associated with reduced ventilation and its energy cost. VIHT may be useful in blunting the altitude-induced hyperventilation leading to higher Paco2 and improved cognitive function. This study examined the effects of VIHT, compared to control (C) and placebo (PVIHT) groups, on selected measures of executive functioning, including working memory and processing speed (i.e., Stroop Test, Symbol Digit Modalities Test, and Digit Span Forward) at simulated altitude up to 12,000 ft. Associated physiological parameters were also measured. The Digit Span Forward Test did not show improvements after VIHT in any group. The VIHT group, but not C or PVIHT groups, improved significantly (17-30%) on the Stroop Test. Similarly the VIHT group, but not the C and PVIHT groups, improved correct responses (26%) and number of attempts (24%) on the Symbol Digit Modalities Test. In addition, reaction time was also improved (16%). VIHT improved processing speed and working memory during exercise at altitude.

Efficacy of respiratory muscle training in weaning of mechanical ventilation in patients with mechanical ventilation for 48hours or more: A Randomized Controlled Clinical Trial.

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Sandoval Moreno, L M; Casas Quiroga, I C; Wilches Luna, E C; García, A F

2018-02-02

To evaluate the efficacy of respiratory muscular training in the weaning of mechanical ventilation and respiratory muscle strength in patients on mechanical ventilation of 48hours or more. Randomized controlled trial of parallel groups, double-blind. Ambit: Intensive Care Unit of a IV level clinic in the city of Cali. 126 patients in mechanical ventilation for 48hours or more. The experimental group received daily a respiratory muscle training program with treshold, adjusted to 50% of maximal inspiratory pressure, additional to standard care, conventional received standard care of respiratory physiotherapy. MAIN INTEREST VARIABLES: weaning of mechanical ventilation. Other variables evaluated: respiratory muscle strength, requirement of non-invasive mechanical ventilation and frequency of reintubation. intention-to-treat analysis was performed with all variables evaluated and analysis stratified by sepsis condition. There were no statistically significant differences in the median weaning time of the MV between the groups or in the probability of extubation between groups (HR: 0.82 95% CI: 0.55-1.20 P=.29). The maximum inspiratory pressure was increased in the experimental group on average 9.43 (17.48) cmsH20 and in the conventional 5.92 (11.90) cmsH20 (P=.48). The difference between the means of change in maximal inspiratory pressure was 0.46 (P=.83 95%CI -3.85 to -4.78). respiratory muscle training did not demonstrate efficacy in the reduction of the weaning period of mechanical ventilation nor in the increase of respiratory muscle strength in the study population. Registered study at ClinicalTrials.gov (NCT02469064). Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

Subxyphoid pleural drain confers lesser impairment in respiratory muscle strength, oxygenation and lower chest pain after off-pump coronary artery bypass grafting: a randomized controlled trial.

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Cancio, Andreia S A; Guizilini, Solange; Bolzan, Douglas W; Dauar, Renato B; Succi, José E; de Paola, Angelo A V; Carvalho, Antonio C de Camargo; Gomes, Walter J

2012-01-01

To evaluate respiratory muscle strength, oxygenation and chest pain in patients undergoing off-pump coronary artery bypass (OPCAB) using internal thoracic artery grafts comparing pleural drain insertion site at the subxyphoid region versus the lateral region. Forty patients were randomized into two groups in accordance with the pleural drain site. Group II (n = 19) -pleural drain exteriorized in the intercostal space; group (SI) (n = 21) chest tube exteriorized at the subxyphoid region. All patients underwent assessment of respiratory muscle strength (inspiratory and expiratory) on the pre, 1, 3 and 5 postoperative days (POD). Arterial blood gas analysis was collected on the pre and POD1. The chest pain sensation was measured 1, 3 and 5 POD. A significant decrease in respiratory muscle strength (inspiratory and expiratory) was seen in both groups until POD5 (P pleural drainage showed less decrease in respiratory muscle strength, better preservation of blood oxygenation and reduced thoracic pain compared to patients with intercostal drain on early OPCAB postoperative.

Abdominal Muscle Activity during Mechanical Ventilation Increases Lung Injury in Severe Acute Respiratory Distress Syndrome.

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Xianming Zhang

Full Text Available It has proved that muscle paralysis was more protective for injured lung in severe acute respiratory distress syndrome (ARDS, but the precise mechanism is not clear. The purpose of this study was to test the hypothesis that abdominal muscle activity during mechanically ventilation increases lung injury in severe ARDS.Eighteen male Beagles were studied under mechanical ventilation with anesthesia. Severe ARDS was induced by repetitive oleic acid infusion. After lung injury, Beagles were randomly assigned into spontaneous breathing group (BIPAPSB and abdominal muscle paralysis group (BIPAPAP. All groups were ventilated with BIPAP model for 8h, and the high pressure titrated to reached a tidal volume of 6ml/kg, the low pressure was set at 10 cmH2O, with I:E ratio 1:1, and respiratory rate adjusted to a PaCO2 of 35-60 mmHg. Six Beagles without ventilator support comprised the control group. Respiratory variables, end-expiratory volume (EELV and gas exchange were assessed during mechanical ventilation. The levels of Interleukin (IL-6, IL-8 in lung tissue and plasma were measured by qRT-PCR and ELISA respectively. Lung injury scores were determined at end of the experiment.For the comparable ventilator setting, as compared with BIPAPSB group, the BIPAPAP group presented higher EELV (427±47 vs. 366±38 ml and oxygenation index (293±36 vs. 226±31 mmHg, lower levels of IL-6(216.6±48.0 vs. 297.5±71.2 pg/ml and IL-8(246.8±78.2 vs. 357.5±69.3 pg/ml in plasma, and lower express levels of IL-6 mRNA (15.0±3.8 vs. 21.2±3.7 and IL-8 mRNA (18.9±6.8 vs. 29.5±7.9 in lung tissues. In addition, less lung histopathology injury were revealed in the BIPAPAP group (22.5±2.0 vs. 25.2±2.1.Abdominal muscle activity during mechanically ventilation is one of the injurious factors in severe ARDS, so abdominal muscle paralysis might be an effective strategy to minimize ventilator-induce lung injury.

Abdominal Muscle Activity during Mechanical Ventilation Increases Lung Injury in Severe Acute Respiratory Distress Syndrome.

Science.gov (United States)

Zhang, Xianming; Wu, Weiliang; Zhu, Yongcheng; Jiang, Ying; Du, Juan; Chen, Rongchang

2016-01-01

It has proved that muscle paralysis was more protective for injured lung in severe acute respiratory distress syndrome (ARDS), but the precise mechanism is not clear. The purpose of this study was to test the hypothesis that abdominal muscle activity during mechanically ventilation increases lung injury in severe ARDS. Eighteen male Beagles were studied under mechanical ventilation with anesthesia. Severe ARDS was induced by repetitive oleic acid infusion. After lung injury, Beagles were randomly assigned into spontaneous breathing group (BIPAPSB) and abdominal muscle paralysis group (BIPAPAP). All groups were ventilated with BIPAP model for 8h, and the high pressure titrated to reached a tidal volume of 6ml/kg, the low pressure was set at 10 cmH2O, with I:E ratio 1:1, and respiratory rate adjusted to a PaCO2 of 35-60 mmHg. Six Beagles without ventilator support comprised the control group. Respiratory variables, end-expiratory volume (EELV) and gas exchange were assessed during mechanical ventilation. The levels of Interleukin (IL)-6, IL-8 in lung tissue and plasma were measured by qRT-PCR and ELISA respectively. Lung injury scores were determined at end of the experiment. For the comparable ventilator setting, as compared with BIPAPSB group, the BIPAPAP group presented higher EELV (427±47 vs. 366±38 ml) and oxygenation index (293±36 vs. 226±31 mmHg), lower levels of IL-6(216.6±48.0 vs. 297.5±71.2 pg/ml) and IL-8(246.8±78.2 vs. 357.5±69.3 pg/ml) in plasma, and lower express levels of IL-6 mRNA (15.0±3.8 vs. 21.2±3.7) and IL-8 mRNA (18.9±6.8 vs. 29.5±7.9) in lung tissues. In addition, less lung histopathology injury were revealed in the BIPAPAP group (22.5±2.0 vs. 25.2±2.1). Abdominal muscle activity during mechanically ventilation is one of the injurious factors in severe ARDS, so abdominal muscle paralysis might be an effective strategy to minimize ventilator-induce lung injury.

Sarcopenia and frailty in chronic respiratory disease

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Bone, Anna E; Hepgul, Nilay; Kon, Samantha

2017-01-01

Sarcopenia and frailty are geriatric syndromes characterized by multisystem decline, which are related to and reflected by markers of skeletal muscle dysfunction. In older people, sarcopenia and frailty have been used for risk stratification, to predict adverse outcomes and to prompt intervention aimed at preventing decline in those at greatest risk. In this review, we examine sarcopenia and frailty in the context of chronic respiratory disease, providing an overview of the common assessments tools and studies to date in the field. We contrast assessments of sarcopenia, which consider muscle mass and function, with assessments of frailty, which often additionally consider social, cognitive and psychological domains. Frailty is emerging as an important syndrome in respiratory disease, being strongly associated with poor outcome. We also unpick the relationship between sarcopenia, frailty and skeletal muscle dysfunction in chronic respiratory disease and reveal these as interlinked but distinct clinical phenotypes. Suggested areas for future work include the application of sarcopenia and frailty models to restrictive diseases and population-based samples, prospective prognostic assessments of sarcopenia and frailty in relation to common multidimensional indices, plus the investigation of exercise, nutritional and pharmacological strategies to prevent or treat sarcopenia and frailty in chronic respiratory disease. PMID:27923981

Effects of non-fatiguing respiratory muscle loading induced by expiratory flow limitation during strenuous incremental cycle exercise on metabolic stress and circulating natural killer cells.

Science.gov (United States)

Rolland-Debord, Camille; Morelot-Panzini, Capucine; Similowski, Thomas; Duranti, Roberto; Laveneziana, Pierantonio

2017-12-01

Exercise induces release of cytokines and increase of circulating natural killers (NK) lymphocyte during strong activation of respiratory muscles. We hypothesised that non-fatiguing respiratory muscle loading during exercise causes an increase in NK cells and in metabolic stress indices. Heart rate (HR), ventilation (VE), oesophageal pressure (Pes), oxygen consumption (VO 2 ), dyspnoea and leg effort were measured in eight healthy humans (five men and three women, average age of 31 ± 4 years and body weight of 68 ± 10 kg), performing an incremental exercise testing on a cycle ergometer under control condition and expiratory flow limitation (FL) achieved by putting a Starling resistor. Blood samples were obtained at baseline, at peak of exercise and at iso-workload corresponding to that reached at the peak of FL exercise during control exercise. Diaphragmatic fatigue was evaluated by measuring the tension time index of the diaphragm. Respiratory muscle overloading caused an earlier interruption of exercise. Diaphragmatic fatigue did not occur in the two conditions. At peak of flow-limited exercise compared to iso-workload, HR, peak inspiratory and expiratory Pes, NK cells and norepinephrine were significantly higher. The number of NK cells was significantly related to ΔPes (i.e. difference between the most and the less negative Pes) and plasmatic catecholamines. Loading of respiratory muscles is able to cause an increase of NK cells provided that activation of respiratory muscles is intense enough to induce a significant metabolic stress.

Respiratory muscle endurance training reduces chronic neck pain: A pilot study.

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Wirth, B; Ferreira, T Duarte; Mittelholzer, M; Humphreys, B K; Boutellier, U

2016-11-21

Patients with chronic neck pain show also respiratory dysfunctions. To investigate the effects of respiratory muscle endurance training (RMET) on chronic neck pain. In this pilot study (single-subject design: 3 baseline measurements, 4 measurements during RMET), 15 neck patients (49.3 ± 13.7 years; 13 females) conducted 20 sessions of home-based RMET using a SpiroTiger® (normocapnic hyperpnoea). Maximal voluntary ventilation (MVV), maximal inspiratory (Pimax) and expiratory (Pemax) pressure were measured before and after RMET. Neck flexor endurance, cervical and thoracic mobility, forward head posture, chest wall expansion and self-assessed neck disability [Neck Disability Index (NDI), Bournemouth questionnaire] were weekly assessed. Repeated measure ANOVA (Bonferroni correction) compared the first and last baseline and the last measurement after RMET. RMET significantly increased MVV (p= 0.025), Pimax (p= 0.001) and Pemax (pneck pain. The underlying mechanisms, including blood gas analyses, need further investigation in a randomized controlled study.

Back muscle strength, lifting, and stooped working postures.

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Poulsen, E; Jørgensen, K

1971-09-01

When lifting loads and working in a forward stooped position, the muscles of the back rather than the ligaments and bony structures of the spine should overcome the gravitational forces. Formulae, based on measurements of back muscle strength, for prediction of maximal loads to be lifted, and for the ability to sustain work in a stooped position, have been worked out and tested in practical situations. From tests with 50 male and female subjects the simplest prediction formulae for maximum loads were: max. load = 1.10 x isometric back muscle strength for men; and max. load = 0.95 x isometric back muscle strength - 8 kg for women. Some standard values for maximum lifts and permissible single and repeated lifts have been calculated for men and women separately and are given in Table 1. From tests with 65 rehabilitees it was found that the maximum isometric strength of the back muscles measured at shoulder height should exceed 2/3 of the body weight, if fatigue and/or pain in the back muscles is to be avoided during work in a standing stooped position.

Formoterol attenuates increased oxidative stress and myosin protein loss in respiratory and limb muscles of cancer cachectic rats

Directory of Open Access Journals (Sweden)

Anna Salazar-Degracia

2017-12-01

Full Text Available Muscle mass loss and wasting are characteristic features of patients with chronic conditions including cancer. Therapeutic options are still scarce. We hypothesized that cachexia-induced muscle oxidative stress may be attenuated in response to treatment with beta2-adrenoceptor-selective agonist formoterol in rats. In diaphragm and gastrocnemius of tumor-bearing rats (108 AH-130 Yoshida ascites hepatoma cells inoculated intraperitoneally with and without treatment with formoterol (0.3 mg/kg body weight/day for seven days, daily subcutaneous injection, redox balance (protein oxidation and nitration and antioxidants and muscle proteins (1-dimensional immunoblots, carbonylated proteins (2-dimensional immunoblots, inflammatory cells (immunohistochemistry, and mitochondrial respiratory chain (MRC complex activities were explored. In the gastrocnemius, but not the diaphragm, of cancer cachectic rats compared to the controls, protein oxidation and nitration levels were increased, several functional and structural proteins were carbonylated, and in both study muscles, myosin content was reduced, inflammatory cell counts were greater, while no significant differences were seen in MRC complex activities (I, II, and IV. Treatment of cachectic rats with formoterol attenuated all the events in both respiratory and limb muscles. In this in vivo model of cancer-cachectic rats, the diaphragm is more resistant to oxidative stress. Formoterol treatment attenuated the rise in oxidative stress in the limb muscles, inflammatory cell infiltration, and the loss of myosin content seen in both study muscles, whereas no effects were observed in the MRC complex activities. These findings have therapeutic implications as they demonstrate beneficial effects of the beta2 agonist through decreased protein oxidation and inflammation in cachectic muscles, especially the gastrocnemius.

The effect of ventilatory muscle training on respiratory function and capacity in ambulatory and bed-ridden patients with neuromuscular disease.

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Gross, D; Meiner, Z

1993-08-01

Most patients with neuromuscular disease develop muscle weakness, including the ventilatory muscles leading to respiratory difficulty and, at times, respiratory insufficiency. We studied the effect of ventilatory muscle training on the ventilatory function and capacity of patients with various types of neuromuscular disease. The ambulatory patients were divided into three major groups. Group I (n = 6) patients with motor neuron disease (MND), such as amyotrophic latera sclerosis; Group II (n = 11) patients with myoneural junction disease (MNJ), such as myasthenia gravis and: Group III (n = 7) patients with muscle diseases such as progressive muscular disease. Patients were evaluated for their neuromuscular diagnosis and status of the disease. A complete physical examination and the various neuromuscular tests were performed. A complete respiratory evaluation was applied: pulmonary function tests (PFT), maximum inspiratory pressure (MIP). Patients then started ventilatory muscle training by resistive breathing, as a prophylactic treatment, for 10 min, three times daily, with a resistance which would induce fatigue. All tests were repeated every six weeks, and the results were as follow: forced vital capacity (FVC) changed from 38.8 +/- 12.3 to 53.2 +/- 9.6% (NS) of predicted value in group I, from 49.8 +/- 8.7 to 66.1 +/- 7.5% (p < 0.002) in group II, and from 47.0 +/- 7.5 to 53.3 +/- 7.6% (p < 0.04) in group III. Forced expiratory volume in one second (FEV1) was 34.8 +/- 11.0, 46.3 +/- 5, and 45.1 +/- 9% for the three groups, respectively, and did not change with training.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of transections and electrical coagulations in the medulla oblongata upon the activities in the respiratory muscles of the crucian carp (author's transl)].

Science.gov (United States)

Fukuda, H

1975-06-01

The following conclusions may be drawn from the results in this work. The respiratory cycles are formed by the neuronal machinery in the reticular formation under the posterior part of the vagal motor nucleus. The motor neurones or the neuronal networks composing the motor nucleus of the respiratory muscles tonically discharge the action potentials, when the neurones or the networks are released from the inhibitory influences of the interneurones connecting the neuronal machinery to the motor neurones. Furthermore, the interneurones probably generate the tonic discharges after removing the inhibitory influences of the other interneurones or the neuronal machinery on them. A reflex mouth closing is elicited by a mechanical stimulus applying on the upper lip. The motor neurones of the m. adductor mandibulae are activated via only one synapse in the reflex. The reflex action potentials recorded from the motor nerve reduce in amplitude at the resting phase of the nerve in the respiratory cycles. These results suggest that the respiratory motor neurones are by nature spontaneous generators of the tonic action potentials and, in the time of the normal breathing, the tonic activity is interrupted by an inhibitory influence of the neuronal machinery generating the respiratory cycles.

Management of respiratory symptoms in ALS.

LENUS (Irish Health Repository)

Hardiman, Orla

2012-02-01

Respiratory insufficiency is a frequent feature of ALS and is present in almost all cases at some stage of the illness. It is the commonest cause of death in ALS. FVC is used as important endpoint in many clinical trials, and in decision-making events for patients with ALS, although there are limitations to its predictive utility. There are multiple causes of respiratory muscle failure, all of which act to produce a progressive decline in pulmonary function. Diaphragmatic fatigue and weakness, coupled with respiratory muscle weakness, lead to reduced lung compliance and atelectasis. Increased secretions increase the risk of aspiration pneumonia, which further compromises respiratory function. Bulbar dysfunction can lead to nutritional deficiency, which in turn increases the fatigue of respiratory muscles. Early recognition of respiratory decline and symptomatic intervention, including non-invasive ventilation can significantly enhance both quality of life and life expectancy in ALS. Patients with respiratory failure should be advised to consider an advance directive to avoid emergency mechanical ventilation.

Management of respiratory symptoms in ALS.

LENUS (Irish Health Repository)

Hardiman, Orla

2011-03-01

Respiratory insufficiency is a frequent feature of ALS and is present in almost all cases at some stage of the illness. It is the commonest cause of death in ALS. FVC is used as important endpoint in many clinical trials, and in decision-making events for patients with ALS, although there are limitations to its predictive utility. There are multiple causes of respiratory muscle failure, all of which act to produce a progressive decline in pulmonary function. Diaphragmatic fatigue and weakness, coupled with respiratory muscle weakness, lead to reduced lung compliance and atelectasis. Increased secretions increase the risk of aspiration pneumonia, which further compromises respiratory function. Bulbar dysfunction can lead to nutritional deficiency, which in turn increases the fatigue of respiratory muscles. Early recognition of respiratory decline and symptomatic intervention, including non-invasive ventilation can significantly enhance both quality of life and life expectancy in ALS. Patients with respiratory failure should be advised to consider an advance directive to avoid emergency mechanical ventilation.

Predictive equations for respiratory muscle strength according to international and Brazilian guidelines

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Isabela M. B. S. Pessoa

2014-10-01

Full Text Available Background: The maximum static respiratory pressures, namely the maximum inspiratory pressure (MIP and maximum expiratory pressure (MEP, reflect the strength of the respiratory muscles. These measures are simple, non-invasive, and have established diagnostic and prognostic value. This study is the first to examine the maximum respiratory pressures within the Brazilian population according to the recommendations proposed by the American Thoracic Society and European Respiratory Society (ATS/ERS and the Brazilian Thoracic Association (SBPT. Objective: To establish reference equations, mean values, and lower limits of normality for MIP and MEP for each age group and sex, as recommended by the ATS/ERS and SBPT. Method: We recruited 134 Brazilians living in Belo Horizonte, MG, Brazil, aged 20-89 years, with a normal pulmonary function test and a body mass index within the normal range. We used a digital manometer that operationalized the variable maximum average pressure (MIP/MEP. At least five tests were performed for both MIP and MEP to take into account a possible learning effect. Results: We evaluated 74 women and 60 men. The equations were as follows: MIP=63.27-0.55 (age+17.96 (gender+0.58 (weight, r2 of 34% and MEP= - 61.41+2.29 (age - 0.03(age2+33.72 (gender+1.40 (waist, r2 of 49%. Conclusion: In clinical practice, these equations could be used to calculate the predicted values of MIP and MEP for the Brazilian population.

Evidence towards improved estimation of respiratory muscle effort from diaphragm mechanomyographic signals with cardiac vibration interference using sample entropy with fixed tolerance values.

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Leonardo Sarlabous

Full Text Available The analysis of amplitude parameters of the diaphragm mechanomyographic (MMGdi signal is a non-invasive technique to assess respiratory muscle effort and to detect and quantify the severity of respiratory muscle weakness. The amplitude of the MMGdi signal is usually evaluated using the average rectified value or the root mean square of the signal. However, these estimations are greatly affected by the presence of cardiac vibration or mechanocardiographic (MCG noise. In this study, we present a method for improving the estimation of the respiratory muscle effort from MMGdi signals that is robust to the presence of MCG. This method is based on the calculation of the sample entropy using fixed tolerance values (fSampEn, that is, with tolerance values that are not normalized by the local standard deviation of the window analyzed. The behavior of the fSampEn parameter was tested in synthesized mechanomyographic signals, with different ratios between the amplitude of the MCG and clean mechanomyographic components. As an example of application of this technique, the use of fSampEn was explored also in recorded MMGdi signals, with different inspiratory loads. The results with both synthetic and recorded signals indicate that the entropy parameter is less affected by the MCG noise, especially at low signal-to-noise ratios. Therefore, we believe that the proposed fSampEn parameter could improve estimates of respiratory muscle effort from MMGdi signals with the presence of MCG interference.

Respiratory muscle strength in relation to sarcopenia in elderly cardiac patients.

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Izawa, Kazuhiro P; Watanabe, Satoshi; Oka, Koichiro; Kasahara, Yusuke; Morio, Yuji; Hiraki, Koji; Hirano, Yasuyuki; Omori, Yutaka; Suzuki, Norio; Kida, Keisuke; Suzuki, Kengo; Akashi, Yoshihiro J

2016-12-01

Little information exists on the relation between respiratory muscle strength such as maximum inspiratory muscle pressure (MIP) and sarcopenia in elderly cardiac patients. The present study aimed to determine the differences in MIP, and cutoff values for MIP according to sarcopenia in elderly cardiac patients. We enrolled 63 consecutive elderly male patients aged ≥65 years with cardiac disease in this cross-sectional study. Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People algorithm, and, accordingly, the patients were divided into two groups: the sarcopenia group (n = 24) and non-sarcopenia group (n = 39). The prevalence of sarcopenia in cardiac patients and MIP in the patients with and without sarcopenia were assessed to determine cutoff values of MIP. After adjustment for body mass index, the MIP in the sarcopenia group was significantly lower than that in the non-sarcopenia group (54.7 ± 36.8 cmH 2 O; 95 % CI 42.5-72.6 vs. 80.7 ± 34.7 cmH 2 O; 95 % CI 69.5-92.0; F = 4.89, p = 0.029). A receiver-operating characteristic curve analysis of patients with and without sarcopenia identified a cutoff value for MIP of 55.6 cmH 2 O, with a sensitivity of 0.76, 1-specificity of 0.37, and AUC of 0.70 (95 % CI 0.56-0.83; p = 0.01) in the study patients. Compared with elderly cardiac patients without sarcopenia, MIP in those with sarcopenia may be negatively affected. The MIP cutoff value reported here may be a useful minimum target value for identifying elderly male cardiac patients with sarcopenia.

Lung volume recruitment acutely increases respiratory system compliance in individuals with severe respiratory muscle weakness

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Yannick Molgat-Seon

2017-03-01

Full Text Available The aim of the present study was to determine whether lung volume recruitment (LVR acutely increases respiratory system compliance (Crs in individuals with severe respiratory muscle weakness (RMW. Individuals with RMW resulting from neuromuscular disease or quadriplegia (n=12 and healthy controls (n=12 underwent pulmonary function testing and the measurement of Crs at baseline, immediately after, 1 h after and 2 h after a single standardised session of LVR. The LVR session involved 10 consecutive supramaximal lung inflations with a manual resuscitation bag to the highest tolerable mouth pressure or a maximum of 50 cmH2O. Each LVR inflation was followed by brief breath-hold and a maximal expiration to residual volume. At baseline, individuals with RMW had lower Crs than controls (37±5 cmH2O versus 109±10 mL·cmH2O−1, p0.05. LVR had no significant effect on measures of pulmonary function at any time point in either group (all p>0.05. During inflations, mean arterial pressure decreased significantly relative to baseline by 10.4±2.8 mmHg and 17.3±3.0 mmHg in individuals with RMW and controls, respectively (both p<0.05. LVR acutely increases Crs in individuals with RMW. However, the high airway pressures during inflations cause reductions in mean arterial pressure that should be considered when applying this technique.

Increased respiratory neural drive and work of breathing in exercise-induced laryngeal obstruction.

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Walsted, Emil S; Faisal, Azmy; Jolley, Caroline J; Swanton, Laura L; Pavitt, Matthew J; Luo, Yuan-Ming; Backer, Vibeke; Polkey, Michael I; Hull, James H

2018-02-01

Exercise-induced laryngeal obstruction (EILO), a phenomenon in which the larynx closes inappropriately during physical activity, is a prevalent cause of exertional dyspnea in young individuals. The physiological ventilatory impact of EILO and its relationship to dyspnea are poorly understood. The objective of this study was to evaluate exercise-related changes in laryngeal aperture on ventilation, pulmonary mechanics, and respiratory neural drive. We prospectively evaluated 12 subjects (6 with EILO and 6 healthy age- and gender-matched controls). Subjects underwent baseline spirometry and a symptom-limited incremental exercise test with simultaneous and synchronized recording of endoscopic video and gastric, esophageal, and transdiaphragmatic pressures, diaphragm electromyography, and respiratory airflow. The EILO and control groups had similar peak work rates and minute ventilation (V̇e) (work rate: 227 ± 35 vs. 237 ± 35 W; V̇e: 103 ± 20 vs. 98 ± 23 l/min; P > 0.05). At submaximal work rates (140-240 W), subjects with EILO demonstrated increased work of breathing ( P respiratory neural drive ( P respiratory mechanics and diaphragm electromyography with endoscopic video, we demonstrate, for the first time, increased work of breathing and respiratory neural drive in association with the development of EILO. Future detailed investigations are now needed to understand the role of upper airway closure in causing exertional dyspnea and exercise limitation. NEW & NOTEWORTHY Exercise-induced laryngeal obstruction is a prevalent cause of exertional dyspnea in young individuals; yet, how laryngeal closure affects breathing is unknown. In this study we synchronized endoscopic video with respiratory physiological measurements, thus providing the first detailed commensurate assessment of respiratory mechanics and neural drive in relation to laryngeal closure. Laryngeal closure was associated with increased work of breathing and respiratory neural drive preceded by an

Work related perceived stress and muscle activity during standardized computer work among female computer users

DEFF Research Database (Denmark)

Larsman, P; Thorn, S; Søgaard, K

2009-01-01

The current study investigated the associations between work-related perceived stress and surface electromyographic (sEMG) parameters (muscle activity and muscle rest) during standardized simulated computer work (typing, editing, precision, and Stroop tasks). It was part of the European case......-control study, NEW (Neuromuscular assessment in the Elderly Worker). The present cross-sectional study was based on a questionnaire survey and sEMG measurements among Danish and Swedish female computer users aged 45 or older (n=49). The results show associations between work-related perceived stress...... and trapezius muscle activity and rest during standardized simulated computer work, and provide partial empirical support for the hypothesized pathway of stress induced muscle activity in the association between an adverse psychosocial work environment and musculoskeletal symptoms in the neck and shoulder....

Time-courses of lung function and respiratory muscle pressure generating capacity after spinal cord injury : a prospective cohort study

NARCIS (Netherlands)

Mueller, Gabi; de Groot, Sonja; van der Woude, Lucas; Hopman, Maria T E

OBJECTIVE: To investigate the time-courses of lung function and respiratory muscle pressure generating capacity after spinal cord injury. DESIGN: Multi-centre, prospective cohort study. SUBJECTS: One hundred and nine subjects with recent, motor complete spinal cord injury. METHODS: Lung function and

High prevalence of respiratory muscle weakness in hospitalized acute heart failure elderly patients.

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Pedro Verissimo

Full Text Available Respiratory Muscle Weakness (RMW has been defined when the maximum inspiratory pressure (MIP is lower than 70% of the predictive value. The prevalence of RMW in chronic heart failure patients is 30 to 50%. So far there are no studies on the prevalence of RMW in acute heart failure (AHF patients.Evaluate the prevalence of RMW in patients admitted because of AHF and the condition of respiratory muscle strength on discharge from the hospital.Sixty-three patients had their MIP measured on two occasions: at the beginning of the hospital stay, after they had reached respiratory, hemodynamic and clinical stability and before discharge from the hospital. The apparatus and technique to measure MIP were adapted because of age-related limitations of the patients. Data on cardiac ejection fraction, ECG, brain natriuretic peptide (BNP levels and on the use of noninvasive ventilation (NIV were collected.The mean age of the 63 patients under study was 75 years. On admission the mean ejection fraction was 33% (95% CI: 31-35 and the BNP hormone median value was 726.5 pg/ml (range: 217 to 2283 pg/ml; 65% of the patients used NIV. The median value of MIP measured after clinical stabilization was -52.7 cmH2O (range: -20 to -120 cmH2O; 76% of the patients had MIP values below 70% of the predictive value. On discharge, after a median hospital stay of 11 days, the median MIP was -53.5 cmH2O (range:-20 to -150 cmH2O; 71% of the patients maintained their MIP values below 70% of the predictive value. The differences found were not statistically significant.Elderly patients admitted with AHF may present a high prevalence of RMW on admission; this condition may be maintained at similar levels on discharge in a large percentage of these patients, even after clinical stabilization of the heart condition.

Assessment of respiratory muscle strength in children according to the classification of body mass index

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George Jung da Rosa

2014-06-01

Full Text Available OBJECTIVE: To assess and compare the respiratory muscle strength among eutrophic, overweight and obese school children, as well as to identify anthropometric and respiratory variables related to the results.METHODS: Cross-sectional survey with healthy schoolchildren aged 7-9 years old, divided into three groups: Normal weight, Overweight and Obese. The International Study of Asthma and Allergies in Childhood (ISAAC questionnaire was applied. The body mass index (BMI was evaluated, as well as the forced expiratory volume in one second (FEV1 with a portable digital device. The maximal inspiratory and expiratory pressures (MIP and MEP were measured by a digital manometer. Comparisons between the groups were made by Kruskal-Wallis test. Spearman's correlation coefficient was used to analyze the correlations among the variables.RESULTS: MIP of eutrophic school children was higher than MIP found in overweight (p=0.043 and obese (p=0.013 children. MIP was correlated with BMI percentile and weight classification (r=-0.214 and r=-0.256 and MEP was correlated with height (r=0.328. Both pressures showed strong correlation with each other in all analyses (r≥0.773, and less correlation with FEV1 (MIP - r=0.362 and MEP - r=0.494. FEV1 correlated with MEP in all groups (r: 0.429 - 0.569 and with MIP in Obese Group (r=0.565. Age was correlated with FEV1 (r=0.578, MIP (r=0.281 and MEP (r=0.328.CONCLUSIONS: Overweight and obese children showed lower MIP values, compared to eutrophic ones. The findings point to the influence of anthropometric variables on respiratory muscle strength in children.

Neuromuscular disease and respiratory physiology in children: putting lung function into perspective.

Science.gov (United States)

Fauroux, Brigitte; Khirani, Sonia

2014-08-01

Neuromuscular diseases represent a heterogeneous group of disorders of the muscle, nerve or neuromuscular junction. The respiratory muscles are rarely spared in neuromuscular diseases even if the type of muscle involvement, severity and time course greatly varies among the different diseases. Diagnosis of respiratory muscle weakness is crucial because of the importance of respiratory morbidity and mortality. Presently, routine respiratory evaluation is based on non-invasive volitional tests, such as the measurement of lung volumes, spirometry and the maximal static pressures, which may be difficult or impossible to obtain in some young children. Other tools or parameters are thus needed to assess the respiratory muscle weakness and its consequences in young children. The measurement of oesogastric pressures can be helpful as they allow the diagnosis and quantification of paradoxical breathing, as well as the assessment of the strength of the inspiratory and expiratory muscles by means of the oesophageal pressure during a maximal sniff and of the gastric pressure during a maximal cough. Sleep assessment should also be part of the respiratory evaluation of children with neuromuscular disease with at least the recording of nocturnal gas exchange if polysomnography is not possible or unavailable. This improvement in the assessment of respiratory muscle performance may increase our understanding of the respiratory pathophysiology of the different neuromuscular diseases, improve patient care, and guide research and innovative therapies by identifying and validating respiratory parameters. © 2014 Asian Pacific Society of Respirology.

Motor function and respiratory capacity in patients with late-onset pompe disease

DEFF Research Database (Denmark)

Illes, Zsolt; Mike, Andrea; Trauninger, Anita

2014-01-01

Introduction: The relationship between skeletal muscle strength and respiratory dysfunction in Pompe disease has not been examined by quantitative methods. We investigated correlations among lower extremity proximal muscle strength, respiratory function, and motor performance. Methods: Concentric...... strength of the knee extensor and flexor muscles were measured with a dynamometer, and pulmonary function was evaluated using spirometry in 7 adult patients. The six-minute walk test and the four-step stair-climb test were used for assessing aerobic endurance and anaerobic power, respectively. Results......: Anaerobic motor performance correlated with strength of both thigh muscles. Respiratory function did not correlate with either muscle strength or motor function performance. Conclusions: Respiratory and lower extremity proximal muscles could be differentially affected by the disease in individual patients...

Work behaviors of artificial muscle based on cation driven polypyrrole.

Science.gov (United States)

Fujisue, Hisashi; Sendai, Tomokazu; Yamato, Kentaro; Takashima, Wataru; Kaneto, Keiichi

2007-06-01

A soft actuator mimicking natural muscles (artificial muscle) has been developed using a flexible conducting polymer of polypyrrole films, which were driven by electrical stimulus in a saline solution. The work characteristics were studied under various load stresses and found to behave like natural muscles. The artificial muscles shrunk and stiffened by the positive electrical stimulus by 2-3% at the maximum force of 5 MPa, and relaxed by application of negative voltages. At larger load stresses, the artificial muscle shrunk slowly as natural muscles do. The driving current also lasted longer at larger loads, indicating that the muscle sensed the magnitude of the load stress. During contraction of the muscle, the conversion efficiency from the electrical input and mechanical output energies was estimated to be around 0.06%. The maximum volumetric work was approximately estimated to be 100 kJ m(-3). These figures are unexpectedly small compared with those of natural muscles.

Reliability and validity of the test of incremental respiratory endurance measures of inspiratory muscle performance in COPD

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Formiga MF

2018-05-01

Full Text Available Magno F Formiga,1,2 Kathryn E Roach,1 Isabel Vital,3 Gisel Urdaneta,3 Kira Balestrini,3 Rafael A Calderon-Candelario,3,4 Michael A Campos,3,4,* Lawrence P Cahalin1,* 1Department of Physical Therapy, University of Miami Miller School of Medicine, Coral Gables, FL, USA; 2CAPES Foundation, Ministry of Education of Brazil, Brasilia, Brazil; 3Pulmonary Section, Miami Veterans Administration Medical Center, Miami, FL, USA; 4Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, University of Miami Miller School of Medicine, Miami, FL, USA *These authors contributed equally to this work Purpose: The Test of Incremental Respiratory Endurance (TIRE provides a comprehensive assessment of inspiratory muscle performance by measuring maximal inspiratory pressure (MIP over time. The integration of MIP over inspiratory duration (ID provides the sustained maximal inspiratory pressure (SMIP. Evidence on the reliability and validity of these measurements in COPD is not currently available. Therefore, we assessed the reliability, responsiveness and construct validity of the TIRE measures of inspiratory muscle performance in subjects with COPD. Patients and methods: Test–retest reliability, known-groups and convergent validity assessments were implemented simultaneously in 81 male subjects with mild to very severe COPD. TIRE measures were obtained using the portable PrO2 device, following standard guidelines. Results: All TIRE measures were found to be highly reliable, with SMIP demonstrating the strongest test–retest reliability with a nearly perfect intraclass correlation coefficient (ICC of 0.99, while MIP and ID clustered closely together behind SMIP with ICC values of about 0.97. Our findings also demonstrated known-groups validity of all TIRE measures, with SMIP and ID yielding larger effect sizes when compared to MIP in distinguishing between subjects of different COPD status. Finally, our analyses confirmed convergent validity for both SMIP

Effects of visually demanding near work on trapezius muscle activity.

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Zetterberg, C; Forsman, M; Richter, H O

2013-10-01

Poor visual ergonomics is associated with visual and neck/shoulder discomfort, but the relation between visual demands and neck/shoulder muscle activity is unclear. The aims of this study were to investigate whether trapezius muscle activity was affected by: (i) eye-lens accommodation; (ii) incongruence between accommodation and convergence; and (iii) presence of neck/shoulder discomfort. Sixty-six participants (33 controls and 33 with neck pain) performed visually demanding near work under four different trial-lens conditions. Results showed that eye-lens accommodation per se did not affect trapezius muscle activity significantly. However, when incongruence between accommodation and convergence was present, a significant positive relationship between eye-lens accommodation and trapezius muscle activity was found. There were no significant group-differences. It was concluded that incongruence between accommodation and convergence is an important factor in the relation between visually demanding near work and trapezius muscle activity. The relatively low demands on accommodation and convergence in the present study imply that visually demanding near work may contribute to increased muscle activity, and over time to the development of near work related neck/shoulder discomfort. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Risk factors for respiratory work disability in a cohort of pulp mill workers exposed to irritant gases

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Torén Kjell

2011-09-01

Full Text Available Abstract Background The association between chronic respiratory diseases and work disability has been demonstrated a number of times over the past 20 years, but still little is known about work disability in occupational cohorts of workers exposed to respiratory irritants. This study investigated job or task changes due to respiratory problems as an indicator of work disability in pulp mill workers occupationally exposed to irritants. Methods Data about respiratory symptoms and disease diagnoses, socio-demographic variables, occupational exposures, gassing episodes, and reported work changes due to respiratory problems were collected using a questionnaire answered by 3226 pulp mill workers. Information about work history and departments was obtained from personnel files. Incidence and hazard ratios for respiratory work disability were calculated with 95% confidence intervals (CI. Results The incidence of respiratory work disability among these pulp mill workers was 1.6/1000 person-years. The hazard ratios for respiratory work disability were increased for workers reporting gassings (HR 5.3, 95% CI 2.7-10.5 and for those reporting physician-diagnosed asthma, chronic bronchitis, and chronic rhinitis, when analyzed in the same model. Conclusions This cohort study of pulp mill workers found that irritant peak exposure during gassing episodes was a strong predictor of changing work due to respiratory problems, even after adjustment for asthma, chronic bronchitis, and chronic rhinitis.

[Undernutrition in chronic respiratory diseases].

Science.gov (United States)

Zielonka, Tadeusz M; Hadzik-Błaszczyk, Małgorzata

2015-01-01

Respiratory diseases such as asthma, COPD, lung cancer, infections, including also tuberculosis constitute the most frequent diseases in the word. Undernutrition frequently accompanies these diseases. Early diagnosis of malnutrition and implementation of appropriate treatment is very important. A nutritional interview and anthropometric examinations, such as body mass index, fat free mass and fat mass are used to diagnose it. Nutritional therapy affects the course and prognosis of these diseases. Diet should be individually adjusted to the calculated caloric intake that increases during exacerbation of disease, because of increased respiratory effort. Too large supply of energy can cause increase metabolism, higher oxygen consumption and PaCO2 increase each dangerous for patients with respiratory insufficiency. Main source of carbohydrates for these patients should be products with low glycemic index and with high dietary fiber contents. Large meals should be avoided since they cause rapid satiety, abdominal discomfort and have negative impact on the work of the respiratory muscles, especially of the diaphragm. Dietary supplements can be used in case of ineffectiveness of diet or for the patients with severe undernutrition.

Respiratory health effects associated with restoration work in post-Hurricane Katrina New Orleans.

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Rando, Roy J; Lefante, John J; Freyder, Laurie M; Jones, Robert N

2012-01-01

This study examines prevalence of respiratory conditions in New Orleans-area restoration workers after Hurricane Katrina. Between 2007 and 2010, spirometry and respiratory health and occupational questionnaire were administered to 791 New Orleans-area adults who mostly worked in the building construction and maintenance trades or custodial services. The associations between restoration work hours and lung function and prevalence of respiratory symptoms were examined by multiple linear regression, χ², or multiple logistic regression. 74% of participants performed post-Katrina restoration work (median time: 620 hours). Symptoms reported include episodes of transient fever/cough (29%), sinus symptoms (48%), pneumonia (3.7%), and new onset asthma (4.5%). Prevalence rate ratios for post-Katrina sinus symptoms (PRR = 1.3; CI: 1.1, 1.7) and fever and cough (PRR = 1.7; CI: 1.3, 2.4) were significantly elevated overall for those who did restoration work and prevalence increased with restoration work hours. Prevalence rate ratios with restoration work were also elevated for new onset asthma (PRR = 2.2; CI: 0.8, 6.2) and pneumonia (PRR = 1.3; CI: 0.5, 3.2) but were not statistically significant. Overall, lung function was slightly depressed but was not significantly different between those with and without restoration work exposure. Post-Katrina restoration work is associated with moderate adverse effects on respiratory health, including sinusitis and toxic pneumonitis.

Evaluation of lung volumes, vital capacity and respiratory muscle strength after cervical, thoracic and lumbar spinal surgery.

Science.gov (United States)

Oliveira, Marcio Aparecido; Vidotto, Milena Carlos; Nascimento, Oliver Augusto; Almeida, Renato; Santoro, Ilka Lopes; Sperandio, Evandro Fornias; Jardim, José Roberto; Gazzotti, Mariana Rodrigues

2015-01-01

Studies have shown that physiopathological changes to the respiratory system can occur following thoracic and abdominal surgery. Laminectomy is considered to be a peripheral surgical procedure, but it is possible that thoracic spinal surgery exerts a greater influence on lung function. The aim of this study was to evaluate the pulmonary volumes and maximum respiratory pressures of patients undergoing cervical, thoracic or lumbar spinal surgery. Prospective study in a tertiary-level university hospital. Sixty-three patients undergoing laminectomy due to diagnoses of tumors or herniated discs were evaluated. Vital capacity, tidal volume, minute ventilation and maximum respiratory pressures were evaluated preoperatively and on the first and second postoperative days. Possible associations between the respiratory variables and the duration of the operation, surgical diagnosis and smoking status were investigated. Vital capacity and maximum inspiratory pressure presented reductions on the first postoperative day (20.9% and 91.6%, respectively) for thoracic surgery (P = 0.01), and maximum expiratory pressure showed reductions on the first postoperative day in cervical surgery patients (15.3%; P = 0.004). The incidence of pulmonary complications was 3.6%. There were reductions in vital capacity and maximum respiratory pressures during the postoperative period in patients undergoing laminectomy. Surgery in the thoracic region was associated with greater reductions in vital capacity and maximum inspiratory pressure, compared with cervical and lumbar surgery. Thus, surgical manipulation of the thoracic region appears to have more influence on pulmonary function and respiratory muscle action.

Partial muscle carnitine palmitoyltransferase-A deficiency

Energy Technology Data Exchange (ETDEWEB)

Ross, N.S.; Hoppel, C.L.

1987-01-02

After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event.

Partial muscle carnitine palmitoyltransferase-A deficiency

International Nuclear Information System (INIS)

Ross, N.S.; Hoppel, C.L.

1987-01-01

After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event

Respiratory disorders in patients with polymyositis/dermatomyositis

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Olga Alekseyevna Antelava

2014-01-01

Full Text Available Idiopathic inflammatory myopathies (IIM are rare disorders characterized by inflammatory lesions in skeletal muscles. These diseases include polymyositis (PM, dermatomyositis (DM, and inclusion body myositis, which exhibit clinicoimmunological heterogeneity and give different response to therapy. The most frequent manifestation in PM/DM patients is respiratory system dysfunction. The developing respiratory disorders are varied and may outpace the presentation of muscle pathology.

The occurrence of respiratory events in young subjects with a frequent rhythmic masticatory muscle activity: a pilot study.

Science.gov (United States)

Tsujisaka, Akiko; Haraki, Shingo; Nonoue, Shigeru; Mikami, Akira; Adachi, Hiroyoshi; Mizumori, Takahiro; Yatani, Hirofumi; Yoshida, Atsushi; Kato, Takafumi

2018-02-21

Concomitant occurrence of respiratory events can be often overlooked in the clinical practice of SB. This study assessed physiological characteristics of rhythmic masticatory muscle activity (RMMA) and concomitant respiratory events in young SB subjects asymptomatic to obstructive sleep apnea (OSA). Twenty-two subjects (age: 24.1±1.9years; F 8: M 14; BMI: 20.2±1.9kg/m 2 ) were polysomnographically diagnosed as moderate-severe SB. Sleep architecture, oromotor (RMMA and non-specific masseter activity [NSMA]) and apnea/hypopnea events were scored. All subjects showed normal sleep architecture whereas 6 exhibited respiratory events at a mild level of OSA. In all subjects, RMMA predominantly occurred in Stage N1+N2 while NSMA occurred in Stage N1+N2 (approximately 60 %) and in Stage R (up to 30 %). Up to 50% of respiratory events were scored in Stage R. RMMA occurred more frequently in close association (e.g., within 10s) with respiratory events in 6 subjects with OSA than those without. The percentage of RMMA occurring closely to respiratory events was positively correlated with apnea-hypopnea index (AHI) in Stage N1+N2 only while that of NSMA was positively correlated with AHI in Stage N1+N2 and Stage R. A sub-analysis in 6 subjects with OSA, RMMA after respiratory events was followed to arousals while those before respiratory events were mostly associated with central apnea. A subpopulation of young SB subjects can show concomitant respiratory events. Further large sample studies are needed to demonstrate that the occurrence of subclinical respiratory events represents a clinical subtype of SB. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Neurological Respiratory Failure

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Mohan Rudrappa

2018-01-01

Full Text Available West Nile virus infection in humans is mostly asymptomatic. Less than 1% of neuro-invasive cases show a fatality rate of around 10%. Acute flaccid paralysis of respiratory muscles leading to respiratory failure is the most common cause of death. Although the peripheral nervous system can be involved, isolated phrenic nerve palsy leading to respiratory failure is rare and described in only two cases in the English literature. We present another case of neurological respiratory failure due to West Nile virus-induced phrenic nerve palsy. Our case reiterates the rare, but lethal, consequences of West Nile virus infection, and the increase of its awareness among physicians.

Muscle diseases with prominent joint contractures: Main entities and diagnostic strategy.

Science.gov (United States)

Eymard, B; Ferreiro, A; Ben Yaou, R; Stojkovic, T

2013-01-01

Muscle diseases may have various clinical manifestations including muscle weakness, atrophy or hypertrophy and joint contractures. A spectrum of non-muscular manifestations (cardiac, respiratory, cutaneous, central and peripheral nervous system) may be associated. Few of these features are specific. Limb joint contractures or spine rigidity, when prevailing over muscle weakness in ambulant patients, are of high diagnostic value for diagnosis orientation. Within this context, among several disorders, four groups of diseases should systematically come to mind including the collagen VI-related myopathies, the Emery-Dreifuss muscular dystrophies, the SEPN1 and FHL1 related myopathies. More rarely other genetic or acquired myopathies may present with marked contractures. Diagnostic work-up should include a comprehensive assessment including family history, neurological, cardiologic and respiratory evaluations. Paraclinical investigations should minimally include muscle imaging and electromyography. Muscle and skin biopsies as well as protein and molecular analyses usually help to reach a precise diagnosis. We will first describe the main muscle and neuromuscular junction diseases where contractures are typically a prominent symptom of high diagnostic value for diagnosis orientation. In the following chapters, we will present clues for the diagnostic strategy and the main measures to be taken when, at the end of the diagnostic work-up, no definite muscular disease has been identified. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Working experiences of nurses during the Middle East respiratory syndrome outbreak.

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Kang, Hee Sun; Son, Ye Dong; Chae, Sun-Mi; Corte, Colleen

2018-05-30

To explore working experiences of nurses during Middle East respiratory syndrome outbreak. Since the first case of Middle East respiratory syndrome was reported on May 20, 2015 in South Korea, 186 people, including health care workers, were infected, and 36 died. A qualitative descriptive study. Seven focus groups and 3 individual in-depth interviews were conducted from August to December 2015. Content analysis was used. The following 4 major themes emerged: "experiencing burnout owing to the heavy workload," "relying on personal protective equipment for safety," "being busy with catching up with the new guidelines related to Middle East respiratory syndrome," and "caring for suspected or infected patients with caution." Participants experienced burnout because of the high volume of work and expressed safety concerns about being infected. Unclear and frequently changing guidelines were 1 of the common causes of confusion. Participants expressed that they need to be supported while caring for suspected or infected patients. This study showed that creating a supportive and safe work environment is essential by ensuring adequate nurse staffing, supplying best-quality personal protective equipment, and improving communication to provide the quality of care during infection outbreak. © 2018 John Wiley & Sons Australia, Ltd.

Effects of Aging on the Respiratory System.

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Levitzky, Michael G.

1984-01-01

Relates alterations in respiratory system functions occurring with aging to changes in respiratory system structure during the course of life. Main alterations noted include loss of alveolar elastic recoil, alteration in chest wall structure and decreased respiratory muscle strength, and loss of surface area and changes in pulmonary circulation.…

Respiratory mechanics

CERN Document Server

Wilson, Theodore A

2016-01-01

This book thoroughly covers each subfield of respiratory mechanics: pulmonary mechanics, the respiratory pump, and flow. It presents the current understanding of the field and serves as a guide to the scientific literature from the golden age of respiratory mechanics, 1960 - 2010. Specific topics covered include the contributions of surface tension and tissue forces to lung recoil, the gravitational deformation of the lung, and the interdependence forces that act on pulmonary airways and blood vessels. The geometry and kinematics of the ribs is also covered in detail, as well as the respiratory action of the external and internal intercostal muscles, the mechanics of the diaphragm, and the quantitative compartmental models of the chest wall is also described. Additionally, flow in the airways is covered thoroughly, including the wave-speed and viscous expiratory flow-limiting mechanisms; convection, diffusion and the stationary front; and the distribution of ventilation. This is an ideal book for respiratory ...

Effect of Aerobic Exercise Training on Ventilatory Efficiency and Respiratory Drive in Obese Subjects.

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Chlif, Mehdi; Chaouachi, Anis; Ahmaidi, Said

2017-07-01

Obese patients show a decline in exercise capacity and diverse degrees of dyspnea in association with mechanical abnormalities, increased ventilatory requirements secondary to the increased metabolic load, and a greater work of breathing. Consequently, obese patients may be particularly predisposed to the development of respiratory muscle fatigue during exercise. The aim of this study was to assess inspiratory muscle performance during incremental exercise in 19 obese male subjects (body mass index 41 ± 6 kg/m 2 ) after aerobic exercise training using the noninvasive, inspiratory muscle tension-time index (T T0.1 ). Measurements performed included anthropometric parameters, lung function assessed by spirometry, rate of perceived breathlessness with the modified Borg dyspnea scale (0-10), breathing pattern, maximal exercise capacity, and inspiratory muscle performance with a breath-by-breath automated exercise metabolic system during an incremental exercise test. T T0.1 was calculated using the equation, T T0.1 = P 0.1 /P Imax × T I /T tot (where P 0.1 represents mouth occlusion pressure, P Imax is maximal inspiratory pressure, and T I /T tot is the duty cycle). At rest, there was no statistically significant difference for spirometric parameters and cardiorespiratory parameters between pre- and post-training. At maximal exercise, the minute ventilation, the rate of exchange ratio, the rate of perceived breathlessness, and the respiratory muscle performance parameters were not significantly different pre- and post-training; in contrast, tidal volume ( P = .037, effect size = 1.51), breathing frequency ( P = .049, effect size = 0.97), power output ( P = .048, effect size = 0.79), peak oxygen uptake ( P = .02, effect size = 0.92) were significantly higher after training. At comparable work load, training induces lower minute ventilation, mouth occlusion pressure, ratio of occlusion pressure to maximal inspiratory pressure, T T0.1 , and rate of perceived

Aerobic metabolism of human quadriceps muscle: in vivo data parallel measurements on isolated mitochondria

DEFF Research Database (Denmark)

Rasmussen, U.F.; Rasmussen, H.N.; Krustrup, Peter

2001-01-01

The aim of the present study was to examine whether parameters of isolated mitochondria could account for the in vivo maximum oxygen uptake ( O2 max) of human skeletal muscle. O2 max and work performance of the quadriceps muscle of six volunteers were measured in the knee extensor model (range 10......-18 mmol O2 · min 1 · kg 1 at work rates of 22-32 W/kg). Mitochondria were isolated from the same muscle at rest. Strong correlations were obtained between O2 max and a number of mitochondrial parameters (mitochondrial protein, cytochrome aa3, citrate synthase, and respiratory activities). The activities...... of citrate synthase, succinate dehydrogenase, and pyruvate dehydrogenase, measured in isolated mitochondria, corresponded to, respectively, 15, 3, and 1.1 times the rates calculated from O2 max. The respiratory chain activity also appeared sufficient. Fully coupled in vitro respiration, which is limited...

Coordinated Respiratory Motor Activity in Nerves Innervating the Upper Airway Muscles in Rats.

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Satoshi Tachikawa

Full Text Available Maintaining the patency of the upper airway during breathing is of vital importance. The activity of various muscles is related to the patency of the upper airway. In the present study, we examined the respiratory motor activity in the efferent nerves innervating the upper airway muscles to determine the movements of the upper airway during respiration under normocapnic conditions (pH = 7.4 and in hypercapnic acidosis (pH = 7.2. Experiments were performed on arterially perfused decerebrate rats aged between postnatal days 21-35. We recorded the efferent nerve activity in a branch of the cervical spinal nerve innervating the infrahyoid muscles (CN, the hypoglossal nerve (HGN, the external branch of the superior laryngeal nerve (SLN, and the recurrent laryngeal nerve (RLN with the phrenic nerve (PN. Inspiratory nerve discharges were observed in all these nerves under normocapnic conditions. The onset of inspiratory discharges in the CN and HGN was slightly prior to those in the SLN and RLN. When the CO2 concentration in the perfusate was increased from 5% to 8% to prepare for hypercapnic acidosis, the peak amplitudes of the inspiratory discharges in all the recorded nerves were increased. Moreover, hypercapnic acidosis induced pre-inspiratory discharges in the CN, HGN, SLN, and RLN. The onset of pre-inspiratory discharges in the CN, HGN, and SLN was prior to that of discharges in the RLN. These results suggest that the securing of the airway that occurs a certain time before dilation of the glottis may facilitate ventilation and improve hypercapnic acidosis.

Work-Related Respiratory Symptoms and Airway Disease in Hairdressers

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GI Skoufi

2013-04-01

Full Text Available Background: Hairdressers are occupationally exposed to a number of agents in their workplace that result in respiratory symptoms and changes in pulmonary function. Objective: To evaluate associations between occupational exposure and respiratory function and reported symptoms in a group of hairdressers compared to a control group. Methods: A questionnaire on respiratory symptoms and workplace characteristics was completed by 94 hairdressers and 39 age- and sex-matched controls. Spirometry and exhaled nitric oxide (FeNO measurements were also performed. Results: Hairdressers reported more severe dyspnea (p=0.03 and eye (p=0.001 and throat (p=0.007 irritation, compared to the control group, at the workplace; no differences were noted at home. Lower FEV1/FVC (p<0.001 and higher FeNO values (p=0.012 were observed in hairdressers. A larger working area and presence of window ventilation were associated with better pulmonary function. Conclusion: Worsening of symptoms and pulmonary function at workplace, and alleviating the symptoms at home, indicate that they may be related to occupational exposure.

Partnering for optimal respiratory home care: physicians working with respiratory therapists to optimally meet respiratory home care needs.

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Spratt, G; Petty, T L

2001-05-01

The need for respiratory care services continues to increase, reimbursement for those services has decreased, and cost-containment measures have increased the frequency of home health care. Respiratory therapists are well qualified to provide home respiratory care, reduce misallocation of respiratory services, assess patient respiratory status, identify problems and needs, evaluate the effect of the home setting, educate the patient on proper equipment use, monitor patient response to and complications of therapy, monitor equipment functioning, monitor for appropriate infection control procedures, make recommendations for changes to therapy regimen, and adjust therapy under the direction of the physician. Teamwork benefits all parties and offers cost and time savings, improved data collection and communication, higher job satisfaction, and better patient monitoring, education, and quality of life. Respiratory therapists are positioned to optimize treatment efficacy, maximize patient compliance, and minimize hospitalizations among patients receiving respiratory home care.

Upper airway muscles awake and asleep.

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Sériès, Frédéric

2002-06-01

Upper airway (UA) structures are involved in different respiratory and non-respiratory tasks. The coordination of agonist and antagonist UA dilators is responsible for their mechanical function and their ability to maintain UA patency throughout the respiratory cycle. The activity of these muscles is linked with central respiratory activity but also depends on UA pressure changes and is greatly influenced by sleep. UA muscles are involved in determining UA resistance and stability (i.e. closing pressure), and the effect of sleep on these variables may be accounted for by its effect on tonic and phasic skeletal muscle activities. The mechanical effects of UA dilator contraction also depend on their physiological properties (capacity to generate tension in vitro, activity of the anaerobic enzymatic pathway, histo-chemical characteristics that may differ between subjects who may or may not have sleep-related obstructive breathing disorders). These characteristics may represent an adaptive process to an increased resistive loading of these muscles. The apparent discrepancy between the occurrence of UA closure and an increased capacity to generate tension in sleep apnea patients may be due to a reduction in the effectiveness of UA muscle contraction in these patients; such an increase in tissue stiffness could be accounted for by peri-muscular tissue characteristics. Therefore, understanding of UA muscle physiological characteristics should take into account its capacity for force production and its mechanical coupling with other UA tissues. Important research goals for the future will be to integrate these issues with other physiological features of the disease, such as UA size and dimension, histological characteristics of UA tissues and the effect of sleep on muscle function. Such integration will better inform understanding of the role of pharyngeal UA muscles in the pathophysiology of the sleep apnea/hypopnea syndrome.

Building-related risk factors and work-related lower respiratory symptoms in 80 office buildings

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Mendell, M.J.; Naco, G.M.; Wilcox, T.G.; Sieber, W.K.

2002-01-01

We assessed building-related risk factors for lower respiratory symptoms in office workers. The National Institute for Occupational Safety and Health in 1993 collected data during indoor environmental health investigations of workplaces. We used multivariate logistic regression analyses to assess relationships between lower respiratory symptoms in office workers and risk factors plausibly related to microbiologic contamination. Among 2,435 occupants in 80 office buildings, frequent, work-related multiple lower respiratory symptoms were strongly associated, in multivariate models, with two risk factors for microbiologic contamination: poor pan drainage under cooling coils and debris in outside air intake. Associations tended to be stronger among those with a history of physician-diagnosed asthma. These findings suggest that adverse lower respiratory health effects from indoor work environments, although unusual, may occur in relation to poorly designed or maintained ventilation systems, particularly among previously diagnosed asthmatics. These findings require confirmation in more representative buildings.

Building-related risk factors and work-related lower respiratory symptoms in 80 office buildings

International Nuclear Information System (INIS)

Mendell, M.J.; Naco, G.M.; Wilcox, T.G.; Sieber, W.K.

2002-01-01

We assessed building-related risk factors for lower respiratory symptoms in office workers. The National Institute for Occupational Safety and Health in 1993 collected data during indoor environmental health investigations of workplaces. We used multivariate logistic regression analyses to assess relationships between lower respiratory symptoms in office workers and risk factors plausibly related to microbiologic contamination. Among 2,435 occupants in 80 office buildings, frequent, work-related multiple lower respiratory symptoms were strongly associated, in multivariate models, with two risk factors for microbiologic contamination: poor pan drainage under cooling coils and debris in outside air intake. Associations tended to be stronger among those with a history of physician-diagnosed asthma. These findings suggest that adverse lower respiratory health effects from indoor work environments, although unusual, may occur in relation to poorly designed or maintained ventilation systems, particularly among previously diagnosed asthmatics. These findings require confirmation in more representative buildings

Current issues in the respiratory care of patients with amyotrophic lateral sclerosis

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Marco Orsini

2015-10-01

Full Text Available Amyotrophic lateral sclerosis is a progressive neuromuscular disease, resulting in respiratory muscle weakness, reduced pulmonary volumes, ineffective cough, secretion retention, and respiratory failure. Measures as vital capacity, maximal inspiratory and expiratory pressures, sniff nasal inspiratory pressure, cough peak flow and pulse oximetry are recommended to monitor the respiratory function. The patients should be followed up by a multidisciplinary team, focused in improving the quality of life and deal with the respiratory symptoms. The respiratory care approach includes airway clearance techniques, mechanically assisted cough and noninvasive mechanical ventilation. Vaccination and respiratory pharmacological support are also recommended. To date, there is no enough evidence supporting the inspiratory muscle training and diaphragmatic pacing.

Longitudinal association between respiratory muscle strength and cough capacity in persons with spinal cord injury: : An explorative analysis of data from a randomized controlled trial

NARCIS (Netherlands)

Postma, Karin; Vlemmix, Lonneke Y.; Haisma, Janneke A.; de Groot, Sonja; Sluis, Tebbe A. R.; Stam, Henk J.; Bussmann, Johannes B. J.

Objective: To assess the longitudinal association between respiratory muscle strength and cough capacity in persons with recent spinal cord injury. Design: Longitudinal analyses. Subjects: Forty persons with recent spinal cord injury and impaired pulmonary function. Methods: Measurements were

[Effects of noninvasive proportional assist vs pressure support ventilation on respiratory work in chronic obstructive pulmonary disease patients with hypercapnia].

Science.gov (United States)

Zhang, J H; Luo, Q; Zhang, H J; Chen, R C

2017-06-12

Objective: To investigate the effect of noninvasive proportional assist ventilation (PAV) on respiratory work in chronic obstructive pulmonary disease(COPD) patients, in comparison to noninvasive pressure support ventilation(PSV). Methods: Ten severe COPD patients with hypercapnia during acute exacerbation were examined. The baseline inspiratory pressure of PSV (PS) and the assistance level of PAV(PA) were titrated by patients' tolerance. In addition to the baseline PS and PA, an additional decrease by 25% (PS-=75% PS, PA-=75% PA) or increase by 25% (PS+ =125% PS, PA+ =125% PA) of the assist level were applied to the patients. After the assessment of unassisted spontaneous breathing (SB), the patient was placed on the 6 levels of noninvasive-PSV and noninvasive-PAV in random sequence. Each level lasted at least 20 minutes. Respiratory rate (RR), tidal volume (Vt), and respiratory work(Wex, Wip and Wv) were measured. Asynchrony index (AI) was calculated. Results: During ventilation, Vt was significantly higher with each assist level than with SB. The Vt was significant increased with PS+ than with PA+ . An increase in expiratory work(Wex) and decrease in inspiratory work(Wip) were observed respectively, with the increasing assist level. The inspiratory muscles assessed by Wip were more unloaded at PS compared with PA [PS: (1.59±1.27) J/min vs PA: (4.99±3.48) J/min P increased with the increasing assist level of PSV [PS-: (0.46±0.57)%, PS: (1.36±1.24)% PS+ : (5.26±4.77)]. No asynchrony events were observed at PA- and PA. "Runaway" (expiratory asynchrony) was observed during PA+ [AI: (2.62±2.72)%]. Conclusions: Noninvasive-PAV can increase the Vt and decrease the Wip of the COPD patients with hypercapnia and avoid the over-assistance. The "Runaway" will occur at assist level higher than that set by tolerance. Physiological data can monitor the patient's responses and the ventilator-patient interaction, which may provide objective criteria for ventilator setting.

Respiratory Management in the Patient with Spinal Cord Injury

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Rita Galeiras Vázquez

2013-01-01

Full Text Available Spinal cord injuries (SCIs often lead to impairment of the respiratory system and, consequently, restrictive respiratory changes. Paresis or paralysis of the respiratory muscles can lead to respiratory insufficiency, which is dependent on the level and completeness of the injury. Respiratory complications include hypoventilation, a reduction in surfactant production, mucus plugging, atelectasis, and pneumonia. Vital capacity (VC is an indicator of overall pulmonary function; patients with severely impaired VC may require assisted ventilation. It is best to proceed with intubation under controlled circumstances rather than waiting until the condition becomes an emergency. Mechanical ventilation can adversely affect the structure and function of the diaphragm. Early tracheostomy following short orotracheal intubation is probably beneficial in selected patients. Weaning should start as soon as possible, and the best modality is progressive ventilator-free breathing (PVFB. Appropriate candidates can sometimes be freed from mechanical ventilation by electrical stimulation. Respiratory muscle training regimens may improve patients’ inspiratory function following a SCI.

Predictors for return to work for those with occupational respiratory disease: clinical and structural factors.

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Zoeckler, Jeanette M; Cibula, Donald A; Morley, Christopher P; Lax, Michael B

2013-12-01

Few occupational researchers have examined "return to work" among patients with work-related respiratory diseases. In addition, prior studies have emphasized individual patient characteristics rather than a more multi-dimensional approach that includes both clinical and structural factors. A retrospective chart review identified patients with occupational respiratory diseases in the Occupational Health Clinical Center, Syracuse, NY between 1991 and 2009. We assessed predictors of work status using an exploratory, sequential mixed methods research design, multinomial (n = 188) and Cox regressions (n = 130). The findings suggest that patients with an increased number of diagnoses, non-union members, and those who took more than a year before clinical presentation had significantly poorer work status outcomes, after adjusting for age, education level, and relevant diagnoses. Efforts to prevent slow return to work after developing occupational respiratory disease should recognize the importance of timely access to occupational health services, disease severity, union membership, and smoking status. © 2013 Wiley Periodicals, Inc.

Work-Related Health Effects in Swine Building Workers After Respiratory Protection Use

DEFF Research Database (Denmark)

Bønløkke, Jakob Hjort; Veillette, Marc; Mériaux, Anne

2012-01-01

OBJECTIVE:To compare inflammation and lung function in swine workers after periods with and without respiratory protection during work. METHODS:Twenty-three workers were examined before and after two nonprotected work shifts. One shift was preceded by a period with diminished exposure by use...

Diagnostic methods to assess inspiratory and expiratory muscle strength

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Pedro Caruso

2015-04-01

Full Text Available Impairment of (inspiratory and expiratory respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation; and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength.

The Clinical Utilisation of Respiratory Elastance Software (CURE Soft): a bedside software for real-time respiratory mechanics monitoring and mechanical ventilation management.

Science.gov (United States)

Szlavecz, Akos; Chiew, Yeong Shiong; Redmond, Daniel; Beatson, Alex; Glassenbury, Daniel; Corbett, Simon; Major, Vincent; Pretty, Christopher; Shaw, Geoffrey M; Benyo, Balazs; Desaive, Thomas; Chase, J Geoffrey

2014-09-30

Real-time patient respiratory mechanics estimation can be used to guide mechanical ventilation settings, particularly, positive end-expiratory pressure (PEEP). This work presents a software, Clinical Utilisation of Respiratory Elastance (CURE Soft), using a time-varying respiratory elastance model to offer this ability to aid in mechanical ventilation treatment. CURE Soft is a desktop application developed in JAVA. It has two modes of operation, 1) Online real-time monitoring decision support and, 2) Offline for user education purposes, auditing, or reviewing patient care. The CURE Soft has been tested in mechanically ventilated patients with respiratory failure. The clinical protocol, software testing and use of the data were approved by the New Zealand Southern Regional Ethics Committee. Using CURE Soft, patient's respiratory mechanics response to treatment and clinical protocol were monitored. Results showed that the patient's respiratory elastance (Stiffness) changed with the use of muscle relaxants, and responded differently to ventilator settings. This information can be used to guide mechanical ventilation therapy and titrate optimal ventilator PEEP. CURE Soft enables real-time calculation of model-based respiratory mechanics for mechanically ventilated patients. Results showed that the system is able to provide detailed, previously unavailable information on patient-specific respiratory mechanics and response to therapy in real-time. The additional insight available to clinicians provides the potential for improved decision-making, and thus improved patient care and outcomes.

Work-related psychosocial stress as a risk factor for asthma, allergy, and respiratory infections in the Swedish workforce.

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Runeson-Broberg, Roma; Norbäck, Dan

2014-04-01

This study examined the association between work-related psychosocial stress and asthma, atopy, and respiratory infections. 532 randomly selected occupationally active people (272 men, 260 women; M age = 41 yr., SD = 13) in Sweden participated. Information on history of asthma, atopy, and respiratory infections was collected by a postal self-report questionnaire. Work stress was assessed based on the demands-control-support model. Current asthma and respiratory infections were associated with work-related psychosocial stress. When stratified for sex, these associations were only found in men. Associations between low control, low support, and current asthma were found among young participants ( 40 years) low supervisor support was associated with frequent respiratory infections.

Mitochondrial function in human skeletal muscle following high-altitude exposure

DEFF Research Database (Denmark)

Jacobs, Robert A; Boushel, Robert; Wright-Paradis, Cynthia

2013-01-01

Studies regarding mitochondrial modifications in human skeletal muscle following acclimatization to high altitude are conflicting, and these inconsistencies may be due to the prevalence of representing mitochondrial function through static and isolated measurements of specific mitochondrial...... characteristics. The aim of this study, therefore, was to investigate mitochondrial function in response to high-altitude acclimatization through measurements of respiratory control in the vastus lateralis muscle. Skeletal muscle biopsies were obtained from 10 lowland natives prior to and again after a total of 9......-11 days of exposure to 4559 m. High-resolution respirometry was performed on the muscle samples to compare respiratory chain function and respiratory capacities. Respirometric analysis revealed that mitochondrial function was largely unaffected, because high-altitude exposure did not affect the capacity...

Simple artificial training device for respiratory muscle strength and lung volumes in healthy young male and female subjects: A pilot study.

Science.gov (United States)

Leelarungrayub, Jirakrit; Pinkaew, Decha; Yankai, Araya; Chautrakoon, Busaba; Kuntain, Rungtiwa

2017-10-01

The aim of this study was to evaluate the efficiency of a simple artificial device for respiratory muscle strength training and lung volumes using either combined or non-combined exercise with elastic bands in healthy young participants. Forty healthy young participants (20 male and 20 female) aged 19-24 years old were randomized into two main experiments with four sub-groups; (1) artificial device (n = 10) & standard device (n = 10) training, and (2) artificial device training combined with elastic band (EB) exercise (n = 10) & standard device training combined with EB (n = 10) exercise. Respiratory muscle strength with maximal peak inspiratory pressure (PImax), and lung volumes; tidal volume (TV), inspiratory reserve volume (IRV), expiratory reserve volume (ERV) and vital capacity (VC) were evaluated before and after training once daily for 3 weeks. Moreover, the peak dyspnea score and vital sign parameters were compared between the experimental groups after final training. All parameters had no statistical differences (p > 0.5) between the training devices alone and those combined with EB exercise prior to any experiments. Results from the first experiment showed that training with an artificial device increased all parameters (PImax, VC, IRV, ERV) significantly (p artificial device training combined with EB exercise showed a significant increase in all parameters, except for TV, and they were the same as the increased results in training with the standard device combined with EB exercise. There was no significant difference of data between these groups after the training period. Finally, the results of peak dyspnea score and all vital sign parameters from using the artificial device, with or without EB exercise, showed no statistical difference when compared to use of the standard device. This study proposed that a simple artificial device can be used to train the respiratory muscle with or without elastic band exercise in healthy young subjects

M19 modulates skeletal muscle differentiation and insulin secretion in pancreatic β-cells through modulation of respiratory chain activity.

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Linda Cambier

Full Text Available Mitochondrial dysfunction due to nuclear or mitochondrial DNA alterations contributes to multiple diseases such as metabolic myopathies, neurodegenerative disorders, diabetes and cancer. Nevertheless, to date, only half of the estimated 1,500 mitochondrial proteins has been identified, and the function of most of these proteins remains to be determined. Here, we characterize the function of M19, a novel mitochondrial nucleoid protein, in muscle and pancreatic β-cells. We have identified a 13-long amino acid sequence located at the N-terminus of M19 that targets the protein to mitochondria. Furthermore, using RNA interference and over-expression strategies, we demonstrate that M19 modulates mitochondrial oxygen consumption and ATP production, and could therefore regulate the respiratory chain activity. In an effort to determine whether M19 could play a role in the regulation of various cell activities, we show that this nucleoid protein, probably through its modulation of mitochondrial ATP production, acts on late muscle differentiation in myogenic C2C12 cells, and plays a permissive role on insulin secretion under basal glucose conditions in INS-1 pancreatic β-cells. Our results are therefore establishing a functional link between a mitochondrial nucleoid protein and the modulation of respiratory chain activities leading to the regulation of major cellular processes such as myogenesis and insulin secretion.

[Detection of respiratory tract diseases among rural population during the team-work mass screening].

Science.gov (United States)

Abramson, E Z; Galkin, V B; Stepanova, G Ia

1990-01-01

A screening complex for the examination of the rural population has been worked out to detect bronchopulmonary pathology and form groups of risk for respiratory diseases. The complex of methods included compulsory questionnaires and ++fluoro-functional examination, spirometry if indicated and bacterial tests. Out of 1, 131 persons examined, 328 were found to have respiratory diseases. Chronic non-specific respiratory diseases were detected in 103 subjects, including 62 of them having obstructive bronchitis. A risk group developing chronic non-specific respiratory diseases, including 202 persons with disturbed ventilation activity of the lungs, post-tuberculous inadequate changes and other pathology. Pulmonary tuberculosis was registered in 7 subjects. The given data indicate the necessity of a complex examination of the population.

Inspiratory muscle training in bronchiectasis patients: a prospective randomized controlled study.

Science.gov (United States)

Liaw, Mei-Yun; Wang, Yi-Hsi; Tsai, Yu-Chin; Huang, Kuo-Tung; Chang, Pei-Wen; Chen, Yung-Che; Lin, Meng-Chih

2011-06-01

To investigate the efficacy and feasibility of home-based inspiratory muscle training in patients with bronchiectasis. A prospective, single-blind, randomized, controlled study. Outpatient clinic of a tertiary care medical centre. Twenty-six patients with bronchiectasis were randomly divided into inspiratory muscle training and control groups. In the inspiratory muscle training group (n = 13), the training programme started with an intensity of 30% maximal inspiratory pressure (MIP), which was increased by 2 cmH(2)O each week, for 30 minutes daily, 5 days a week for eight weeks. The control group (n = 13) did not receive inspiratory muscle training. Main outcome measures included spirometry, resting oxyhaemoglobin saturation by pulse oximetry (SpO(2)), lowest SpO(2) and Borg Scale during 6-minute walking tests, 6-minute walking distance (6MWD), 6-minute walking work (6M(work)), MIP, maximal expiratory pressure (MEP) and St George's Respiratory Questionnaire. There were significant differences in change from baseline in 6MWD (411.9 (133.5) vs. 473.2 (117.2) m, P = 0.021), 6M(work) (21 051.0 (8286.7) vs. 23 915.5 (8343.0) kg-m, P = 0.022), MIP (60.8 (21.8) vs. 84.6 (29.0) cmH(2)O, P = 0.004), and MEP (72.3 (31.1) vs. 104.2 (35.7) cmH(2)O, P = 0.004) in the inspiratory muscle training group. Significant improvements in both MIP (23.8 (25.3) vs. 2.3 (16.4) cmH(2)O, adjusted P-value = 0.005) and MEP (31.9 (30.8) vs. 11.5 (20.8) cmH(2)O, adjusted P-value = 0.038) levels after adjusting for age by linear regression analysis were observed between groups. An eight-week home-based inspiratory muscle training is feasible and effective in improving both inspiratory and expiratory muscle strength, but has no effect on respiratory function and quality of life in patients with bronchiectasis.

New Combined Scoring System for Predicting Respiratory Failure in Iraqi Patients with Guillain-Barré Syndrome

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Zaki Noah Hasan

2010-09-01

Full Text Available The Guillain-Barré syndrome (GBS is an acute post-infective autoimmune polyradiculoneuropathy, it is the commonest peripheral neuropathy causing respiratory failure. The aim of the study is to use the New Combined Scoring System in anticipating respiratory failure in order to perform elective measures without waiting for emergency situations to occur.
Patients and methods: Fifty patients with GBS were studied. Eight clinical parameters (including progression of patients to maximum weakness, respiratory rate/minute, breath holding
count (the number of digits the patient can count in holding his breath, presence of facial muscle weakness (unilateral or bilateral, presence of weakness of the bulbar muscle, weakness of the neck flexor muscle, and limbs weakness were assessed for each patient and a certain score was given to
each parameter, a designed combined score being constructed by taking into consideration all the above mentioned clinical parameters. Results and discussion: Fifteen patients (30% that were enrolled in our study developed respiratory failure. There was a highly significant statistical association between the development of respiratory failure and the lower grades of (bulbar muscle weakness score, breath holding count scores, neck muscle weakness score, lower limbs and upper limbs weakness score , respiratory rate score and the total sum score above 16 out of 30 (p-value=0.000 . No significant statistical difference was found regarding the progression to maximum weakness (p-value=0.675 and facial muscle weakness (p-value=0.482.
Conclusion: The patients who obtained a combined score (above 16’30 are at great risk of having respiratory failure.

Cycle ergometer and inspiratory muscle training offer modest benefit compared with cycle ergometer alone: a comprehensive assessment in stable COPD patients

Directory of Open Access Journals (Sweden)

Wang K

2017-09-01

Full Text Available Kai Wang,1,* Guang-qiao Zeng,2,* Rui Li,1,* Yu-wen Luo,1 Mei Wang,1 Yu-he Hu,1 Wen-hui Xu,1 Lu-qian Zhou,2 Rong-chang Chen,2 Xin Chen1 1Department of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China; 2Department of Respiratory Medicine, The State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China *These authors contributed equally to this work Background: Cycle ergometer training (CET has been shown to improve exercise performance of the quadriceps muscles in patients with COPD, and inspiratory muscle training (IMT may improve the pressure-generating capacity of the inspiratory muscles. However, the effects of combined CET and IMT remain unclear and there is a lack of comprehensive assessment.Materials and methods: Eighty-one patients with COPD were randomly allocated to three groups: 28 received 8 weeks of CET + IMT (combined training group, 27 received 8 weeks of CET alone (CET group, and 26 only received 8 weeks of free walking (control group. Comprehensive assessment including respiratory muscle strength, exercise capacity, pulmonary function, dyspnea, quality of life, emotional status, nutritional status, and body mass index, airflow obstruction, and exercise capacity index were measured before and after the pulmonary rehabilitation program.Results: Respiratory muscle strength, exercise capacity, inspiratory capacity, dyspnea, quality of life, depression and anxiety, and nutritional status were all improved in the combined training and CET groups when compared with that in the control group (P<0.05 after pulmonary rehabilitation program. Inspiratory muscle strength increased significantly in the combined training group when compared with that in the CET group (ΔPImax [maximal inspiratory pressure] 5.20±0.89 cmH2O vs 1.32±0.91 cmH2O

Respiratory muscle hemodynamic and metabolic adaptations to 16 weeks of training in varsity soccer players: near-infrared spectroscopy measurements during lung function tests (Conference Presentation)

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Harris, R. Luke; Grob, Tanya; Sandhu, Komal; Schwab, Timothy

2017-02-01

The purpose of this study was to test the hypothesis that mobile, wireless near-infrared spectroscopy (NIRS) instruments can be used during standard lung function tests to measure adaptations in respiratory muscle metabolism over weeks to months. In eight varsity soccer players at 0 weeks and after 16 weeks of routine training, commercially available mobile, wireless NIRS instruments were used to measure oxygenation and hemodynamics in the sternocleidomastoid (SCM, accessory inspiration muscle). During maximal expiratory pressure (MEP) and forced vital capacity (FVC) maneuvers we determined peak or antipeak changes relative to baseline in oxygenation and hemodynamics: Δ%Sat (muscle oxygen saturation), ΔtHb (total hemoglobin), ΔO2Hb (oxygenated hemoglobin), and ΔHHb (deoxygenated hemoglobin). Subjects reported that the average training load was 13.3 h/week during the 16 study weeks, compared to 10.4 h/week during 12 prior weeks. After 16 weeks of training compared to 0 weeks we found statistically significant increases in SCM Δ%Sat (57.7%), ΔtHb (55.3%), and ΔO2Hb (56.7%) during MEP maneuvers, and in SCM Δ%Sat (64.8%), ΔtHb (29.4%), and ΔO2Hb (51.6%) during FVC maneuvers. Our data provide preliminary evidence that NIRS measurements during standard lung function tests are sufficiently sensitive to detect improvements or declines in respiratory muscle metabolism over periods of weeks to months due to training, disease, and rehabilitation exercise.

Biofeedback effectiveness to reduce upper limb muscle activity during computer work is muscle specific and time pressure dependent

DEFF Research Database (Denmark)

Vedsted, Pernille; Søgaard, Karen; Blangsted, Anne Katrine

2011-01-01

trapezius (TRA) can reduce bilateral TRA activity but not extensor digitorum communis (EDC) activity; (2) biofeedback from EDC can reduce activity in EDC but not in TRA; (3) biofeedback is more effective in no time constraint than in the time constraint working condition. Eleven healthy women performed......Continuous electromyographic (EMG) activity level is considered a risk factor in developing muscle disorders. EMG biofeedback is known to be useful in reducing EMG activity in working muscles during computer work. The purpose was to test the following hypotheses: (1) unilateral biofeedback from...... computer work during two different working conditions (time constraint/no time constraint) while receiving biofeedback. Biofeedback was given from right TRA or EDC through two modes (visual/auditory) by the use of EMG or mechanomyography as biofeedback source. During control sessions (no biofeedback), EMG...

Breath-taking jobs: a case–control study of respiratory work disability by occupation in Norway

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Fell, AKM; Abrahamsen, R; Henneberger, PK; Svendsen, MV; Andersson, E; Torén, K; Kongerud, J

2016-01-01

Background The current knowledge on respiratory work disability is based on studies that used crude categories of exposure. This may lead to a loss of power, and does not provide sufficient information to allow targeted workplace interventions and follow-up of patients with respiratory symptoms. Objectives The aim of this study was to identify occupations and specific exposures associated with respiratory work disability. Methods In 2013, a self-administered questionnaire was mailed to a random sample of the general population, aged 16–50, in Telemark County, Norway. We defined respiratory work disability as a positive response to the survey question: ‘Have you ever had to change or leave your job because it affected your breathing?’ Occupational exposures were assessed using an asthma-specific job-exposure matrix, and comparison of risks was made for cases and a median of 50 controls per case. Results 247 workers had changed their work because of respiratory symptoms, accounting for 1.7% of the respondents ever employed. The ‘breath-taking jobs’ were cooks/chefs: adjusted OR 3.6 (95% CI 1.6 to 8.0); welders: 5.2 (2.0 to 14); gardeners: 4.5 (1.3 to 15); sheet metal workers: 5.4 (2.0 to 14); cleaners: 5.0 (2.2 to 11); hairdressers: 6.4 (2.5 to 17); and agricultural labourers: 7.4 (2.5 to 22). Job changes were also associated with a variety of occupational exposures, with some differences between men and women. Conclusions Self-report and job-exposure matrix data showed similar findings. For the occupations and exposures associated with job change, preventive measures should be implemented. PMID:27365181

Functional and histopathological identification of the respiratory failure in a DMSXL transgenic mouse model of myotonic dystrophy

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Petrica-Adrian Panaite

2013-05-01

Acute and chronic respiratory failure is one of the major and potentially life-threatening features in individuals with myotonic dystrophy type 1 (DM1. Despite several clinical demonstrations showing respiratory problems in DM1 patients, the mechanisms are still not completely understood. This study was designed to investigate whether the DMSXL transgenic mouse model for DM1 exhibits respiratory disorders and, if so, to identify the pathological changes underlying these respiratory problems. Using pressure plethysmography, we assessed the breathing function in control mice and DMSXL mice generated after large expansions of the CTG repeat in successive generations of DM1 transgenic mice. Statistical analysis of breathing function measurements revealed a significant decrease in the most relevant respiratory parameters in DMSXL mice, indicating impaired respiratory function. Histological and morphometric analysis showed pathological changes in diaphragmatic muscle of DMSXL mice, characterized by an increase in the percentage of type I muscle fibers, the presence of central nuclei, partial denervation of end-plates (EPs and a significant reduction in their size, shape complexity and density of acetylcholine receptors, all of which reflect a possible breakdown in communication between the diaphragmatic muscles fibers and the nerve terminals. Diaphragm muscle abnormalities were accompanied by an accumulation of mutant DMPK RNA foci in muscle fiber nuclei. Moreover, in DMSXL mice, the unmyelinated phrenic afferents are significantly lower. Also in these mice, significant neuronopathy was not detected in either cervical phrenic motor neurons or brainstem respiratory neurons. Because EPs are involved in the transmission of action potentials and the unmyelinated phrenic afferents exert a modulating influence on the respiratory drive, the pathological alterations affecting these structures might underlie the respiratory impairment detected in DMSXL mice. Understanding

Ciguatera fish poisoning with elevated muscle enzymes and abnormal spinal MRI.

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Wasay, Mohammad; Sarangzai, Amanullah; Siddiqi, Ather; Nizami, Qamaruddin

2008-03-01

We report three cases of ciguatera fish poisoning. One patient died secondary to respiratory failure. Two patients showed elevated muscle enzymes and one patients had an abnormal cervical spinal MRI. MRI findings have not been previously described. MRI findings explain the mechanism of the L'hermitte phenomenon (a common complaint) among these patients. Respiratory failure is rare in ciguatera fish poisoning. Our findings suggest this could be related to respiratory muscles involvement.

Breath-taking jobs: a case-control study of respiratory work disability by occupation in Norway.

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Fell, A K; Abrahamsen, R; Henneberger, P K; Svendsen, M V; Andersson, E; Torén, K; Kongerud, J

2016-09-01

The current knowledge on respiratory work disability is based on studies that used crude categories of exposure. This may lead to a loss of power, and does not provide sufficient information to allow targeted workplace interventions and follow-up of patients with respiratory symptoms. The aim of this study was to identify occupations and specific exposures associated with respiratory work disability. In 2013, a self-administered questionnaire was mailed to a random sample of the general population, aged 16-50, in Telemark County, Norway. We defined respiratory work disability as a positive response to the survey question: 'Have you ever had to change or leave your job because it affected your breathing?' Occupational exposures were assessed using an asthma-specific job-exposure matrix, and comparison of risks was made for cases and a median of 50 controls per case. 247 workers had changed their work because of respiratory symptoms, accounting for 1.7% of the respondents ever employed. The 'breath-taking jobs' were cooks/chefs: adjusted OR 3.6 (95% CI 1.6 to 8.0); welders: 5.2 (2.0 to 14); gardeners: 4.5 (1.3 to 15); sheet metal workers: 5.4 (2.0 to 14); cleaners: 5.0 (2.2 to 11); hairdressers: 6.4 (2.5 to 17); and agricultural labourers: 7.4 (2.5 to 22). Job changes were also associated with a variety of occupational exposures, with some differences between men and women. Self-report and job-exposure matrix data showed similar findings. For the occupations and exposures associated with job change, preventive measures should be implemented. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

The energetic benefits of tendon springs in running: is the reduction of muscle work important?

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Holt, Natalie C; Roberts, Thomas J; Askew, Graham N

2014-12-15

The distal muscle-tendon units of cursorial species are commonly composed of short muscle fibres and long, compliant tendons. It is assumed that the ability of these tendons to store and return mechanical energy over the course of a stride, thus avoiding the cyclic absorption and regeneration of mechanical energy by active muscle, offers some metabolic energy savings during running. However, this assumption has not been tested directly. We used muscle ergometry and myothermic measurements to determine the cost of force production in muscles acting isometrically, as they could if mechanical energy was stored and returned by tendon, and undergoing active stretch-shorten cycles, as they would if mechanical energy was absorbed and regenerated by muscle. We found no detectable difference in the cost of force production in isometric cycles compared with stretch-shorten cycles. This result suggests that replacing muscle stretch-shorten work with tendon elastic energy storage and recovery does not reduce the cost of force production. This calls into question the assumption that reduction of muscle work drove the evolution of long distal tendons. We propose that the energetic benefits of tendons are derived primarily from their effect on muscle and limb architecture rather than their ability to reduce the cyclic work of muscle. © 2014. Published by The Company of Biologists Ltd.

A dynamic population-based model for the development of work-related respiratory health effects among bakery workers.

NARCIS (Netherlands)

Warren, N.; Meijster, T.; Heederik, D.; Tielemans, E.

2009-01-01

OBJECTIVES: This paper presents a dynamic population-based model for the development of sensitisation and respiratory symptoms in bakery workers. The model simulates a population of individual workers longitudinally and tracks the development of work-related sensitisation and respiratory symptoms in

A dynamic population-based model for the development of work-related respiratory health effects among bakery workers

NARCIS (Netherlands)

Warren, N.; Meijster, T.; Heederik, D.; Tielemans, E.

2009-01-01

Objectives: This paper presents a dynamic population-based model for the development of sensitisation and respiratory symptoms in bakery workers. The model simulates a population of individual workers longitudinally and tracks the development of work-related sensitisation and respiratory symptoms in

Muscle Deoxygenation Causes Muscle Fatigue

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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.

Diaphragmatic mobility: relationship with lung function, respiratory muscle strength, dyspnea, and physical activity in daily life in patients with COPD.

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Rocha, Flávia Roberta; Brüggemann, Ana Karla Vieira; Francisco, Davi de Souza; Medeiros, Caroline Semprebom de; Rosal, Danielle; Paulin, Elaine

2017-01-01

To evaluate diaphragmatic mobility in relation to lung function, respiratory muscle strength, dyspnea, and physical activity in daily life (PADL) in patients with COPD. We included 25 patients with COPD, classified according to the Global Initiative for Chronic Obstructive Lung Disease criteria, and 25 healthy individuals. For all of the participants, the following were evaluated: anthropometric variables, spirometric parameters, respiratory muscle strength, diaphragmatic mobility (by X-ray), PADL, and the perception of dyspnea. In the COPD group, diaphragmatic mobility was found to correlate with lung function variables, inspiratory muscle strength, and the perception of dyspnea, whereas it did not correlate with expiratory muscle strength or PADL. In patients with COPD, diaphragmatic mobility seems to be associated with airway obstruction and lung hyperinflation, as well as with ventilatory capacity and the perception of dyspnea, although not with PADL. Avaliar a relação da mobilidade diafragmática com a função pulmonar, força muscular respiratória, dispneia e atividade física de vida diária (AFVD) em pacientes com DPOC. Foram avaliados 25 pacientes com diagnóstico de DPOC, classificados de acordo com critérios da Global Initiative for Chronic Obstructive Lung Disease, e 25 indivíduos saudáveis. Todos foram submetidos às seguintes avaliações: mensuração antropométrica, espirometria, força muscular respiratória, mobilidade diafragmática (por radiografia), AFVD e percepção de dispneia. No grupo DPOC, houve correlações da mobilidade diafragmática com variáveis de função pulmonar, força muscular inspiratória e percepção de dispneia. Não houve correlações da mobilidade diafragmática com força muscular expiratória e AFVD. A mobilidade diafragmática parece estar associada tanto com a obstrução das vias aéreas quanto com a hiperinsuflação pulmonar em pacientes com DPOC, assim como com a capacidade ventilatória e percep

Poultry Processing Work and Respiratory Health of Latino Men and Women in North Carolina

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Mirabelli, Maria C.; Chatterjee, Arjun B.; Arcury, Thomas A.; Mora, Dana C.; Blocker, Jill N.; Grzywacz, Joseph G.; Chen, Haiying; Marín, Antonio J.; Schulz, Mark R.; Quandt, Sara A.

2015-01-01

Objective To evaluate associations between poultry processing work and respiratory health among working Latino men and women in North Carolina. Methods Between May 2009 and November 2010, 402 poultry processing workers and 339 workers in a comparison population completed interviewer-administered questionnaires. Of these participants, 279 poultry processing workers and 222 workers in the comparison population also completed spirometry testing to provide measurements of forced expiratory volume in 1 second and forced vital capacity. Results Nine percent of poultry processing workers and 10% of workers in the comparison population reported current asthma. Relative to the comparison population, adjusted mean forced expiratory volume in 1 second and forced vital capacity were lower in the poultry processing population, particularly among men who reported sanitation job activities. Conclusions Despite the low prevalence of respiratory symptoms reported, poultry processing work may affect lung function. PMID:22237034

Morphological and ultrastructural evaluation of the golden retriever muscular dystrophy trachea, lungs, and diaphragm muscle.

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Lessa, Thais Borges; de Abreu, Dilayla Kelly; Rodrigues, Márcio Nogueira; Brólio, Marina Pandolphi; Miglino, Maria Angélica; Ambrósio, Carlos Eduardo

2014-11-01

Duchenne muscular dystrophy (DMD) is a genetic disease, characterized by atrophy and muscle weakness. The respiratory failure is a common cause of early death in patients with DMD. Golden retriever muscular dystrophy (GRMD) is a canine model which has been extensively used for many advances in therapeutics applications. As the patients with DMD, the GRMD frequently died from cardiac and respiratory failure. Observing the respiratory failure in DMD is one of the major causes of mortality we aimed to describe the morphological and ultrastructural data of trachea, lungs (conductive and respiratory portion of the system), and diaphragm muscle using histological and ultrastructural analysis. The diaphragm muscle showed discontinuous fibers architecture, with different diameter; a robust perimysium inflammatory infiltrate and some muscle cells displayed central nuclei. GRMD trachea and lungs presented collagen fibers and in addition, the GRMD lungs showed higher of levels collagen fibers that could limit the alveolar ducts and alveoli distension. Therefore, the most features observed were the collagen areas and fibrosis. We suggested in this study that the collagen remodeling in the trachea, lungs, and diaphragm muscle may increase fibrosis and affect the trachea, lungs, and diaphragm muscle function that can be a major cause of respiratory failure that occur in patients with DMD. © 2014 Wiley Periodicals, Inc.

Respiratory muscle dysfunction in congestive heart failure: clinical correlation and prognostic significance.

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Meyer, F J; Borst, M M; Zugck, C; Kirschke, A; Schellberg, D; Kübler, W; Haass, M

2001-05-01

In congestive heart failure (CHF), the prognostic significance of impaired respiratory muscle strength has not been established. Maximal inspiratory pressure (Pi(max)) was prospectively determined in 244 consecutive patients (207 men) with CHF (ischemic, n=75; idiopathic dilated cardiomyopathy, n=169; age, 54+/-11 years; left ventricular ejection fraction [LVEF], 22+/-10%). Pi(max) was lower in the 244 patients with CHF than in 25 control subjects (7.6+/-3.3 versus 10.5+/-3.7 kPa; P=0.001). The 57 patients (23%) who died during follow-up (23+/-16 months; range, 1 to 48 months) had an even more reduced Pi(max) (6.3+/-3.2 versus 8.1+/-3.2 kPa in survivors; P=0.001). Kaplan-Meier survival curves differentiated between patients subdivided according to quartiles for Pi(max) (P=0.014). Pi(max) was a strong risk predictor in both univariate (P=0.001) and multivariate Cox proportional hazard analyses (P=0.03); multivariate analyses also included NYHA functional class, LVEF, peak oxygen consumption (peak VO(2)), and norepinephrine plasma concentration. The areas under the receiver-operating characteristic curves for prediction of 1-year survival were comparable for Pi(max) and peak VO(2) (area under the curve [AUC], 0.68 versus 0.73; P=0.28), and they improved with the triple combination of Pi(max), peak VO(2), and LVEF (AUC, 0.82; P=0.004 compared with AUC of Pi(max)). In patients with CHF, inspiratory muscle strength is reduced and emerges as a novel, independent predictor of prognosis. Because testing for Pi(max) is simple in clinical practice, it might serve as an additional factor to improve risk stratification and patient selection for cardiac transplantation.

Skeletal, cardiac, and respiratory muscle function and histopathology in the P448Lneo- mouse model of FKRP-deficient muscular dystrophy.

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Yu, Qing; Morales, Melissa; Li, Ning; Fritz, Alexander G; Ruobing, Ren; Blaeser, Anthony; Francois, Ershia; Lu, Qi-Long; Nagaraju, Kanneboyina; Spurney, Christopher F

2018-04-06

Fukutin-related protein (FKRP) mutations are the most common cause of dystroglycanopathies known to cause both limb girdle and congenital muscular dystrophy. The P448Lneo- mouse model has a knock-in mutation in the FKRP gene and develops skeletal, respiratory, and cardiac muscle disease. We studied the natural history of the P448Lneo- mouse model over 9 months and the effects of twice weekly treadmill running. Forelimb and hindlimb grip strength (Columbus Instruments) and overall activity (Omnitech Electronics) assessed skeletal muscle function. Echocardiography was performed using VisualSonics Vevo 770 (FujiFilm VisualSonics). Plethysmography was performed using whole body system (ADInstruments). Histological evaluations included quantification of inflammation, fibrosis, central nucleation, and fiber size variation. P448Lneo- mice had significantly increased normalized tissue weights compared to controls at 9 months of age for the heart, gastrocnemius, soleus, tibialis anterior, quadriceps, and triceps. There were no significant differences seen in forelimb or hindlimb grip strength or activity monitoring in P448Lneo- mice with or without exercise compared to controls. Skeletal muscles demonstrated increased inflammation, fibrosis, central nucleation, and variation in fiber size compared to controls (p muscular dystrophies.

Active biofeedback changes the spatial distribution of upper trapezius muscle activity during computer work

DEFF Research Database (Denmark)

Samani, Afshin; Holtermann, Andreas; Søgaard, Karen

2010-01-01

The aim of this study was to investigate the spatio-temporal effects of advanced biofeedback by inducing active and passive pauses on the trapezius activity pattern using high-density surface electromyography (HD-EMG). Thirteen healthy male subjects performed computer work with superimposed...... benefit of superimposed muscle contraction in relation to the spatial organization of muscle activity during computer work....

Locomotor-Respiratory Coupling in Wheelchair Racing Athletes: A Pilot Study.

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Perret, Claudio; Wenger, Martin; Leicht, Christof A; Goosey-Tolfrey, Victoria L

2016-01-01

In wheelchair racing, respiratory muscles of the rib cage are concomitantly involved in non-ventilatory functions during wheelchair propulsion. However, the relationship between locomotor-respiratory coupling (LRC: the ratio between push and breathing frequency), respiratory parameters and work efficiency is unknown. Therefore, the aim of the present study was to investigate the LRC in wheelchair racers over different race distances. Eight trained and experienced wheelchair racers completed three time-trials over the distances of 400, 800, and 5000 m on a training roller in randomized order. During the time trials, ventilatory and gas exchange variables as well as push frequency were continuously registered to determine possible LRC strategies. Four different coupling ratios were identified, namely 1:1; 2:1, 3:1 as well as a 1:1/2:1 alternating type, respectively. The 2:1 coupling was the most dominant type. The 1:1/2:1 alternating coupling type was found predominantly during the 400 m time-trial. Longer race distances tended to result in an increased coupling ratio (e.g., from 1:1 toward 2:1), and an increase in coupling ratio toward a more efficient respiration was found over the 5000 m distance. A significant correlation (r = 0.80, p respiratory frequency and the respiratory equivalent for oxygen was found for the 400 m and the 800 m time-trials. These findings suggest that a higher coupling ratio indicates enhanced breathing work efficiency with a concomitant deeper and slower respiration during wheelchair racing. Thus, the selection of an appropriate LRC strategy may help to optimize wheelchair racing performance.

Metal Dust Exposure and Respiratory Health of Male Steel Work¬ers in Terengganu, Malaysia

OpenAIRE

Nurul Ainun HAMZAH; Shamsul Bahri MOHD TAMRIN; Noor Hassim ISMAIL

2015-01-01

Background: This cross sectional study was carried out to determine the relationship between metal dust exposure and respiratory health in male steel workers in Terengganu, Malaysia.Methods: Subjects were interviewed using a structured questionnaire from British Medical Research Council (BMRC) Questionnaire regarding respiratory symptoms and were examined their lung function using spirometer.Results: The mean trace metal dusts concentration TWA8 for cobalt and chromium in most of work unit ex...

Amla Enhances Mitochondrial Spare Respiratory Capacity by Increasing Mitochondrial Biogenesis and Antioxidant Systems in a Murine Skeletal Muscle Cell Line

Directory of Open Access Journals (Sweden)

Hirotaka Yamamoto

2016-01-01

Full Text Available Amla is one of the most important plants in Indian traditional medicine and has been shown to improve various age-related disorders while decreasing oxidative stress. Mitochondrial dysfunction is a proposed cause of aging through elevated oxidative stress. In this study, we investigated the effects of Amla on mitochondrial function in C2C12 myotubes, a murine skeletal muscle cell model with abundant mitochondria. Based on cell flux analysis, treatment with an extract of Amla fruit enhanced mitochondrial spare respiratory capacity, which enables cells to overcome various stresses. To further explore the mechanisms underlying these effects on mitochondrial function, we analyzed mitochondrial biogenesis and antioxidant systems, both proposed regulators of mitochondrial spare respiratory capacity. We found that Amla treatment stimulated both systems accompanied by AMPK and Nrf2 activation. Furthermore, we found that Amla treatment exhibited cytoprotective effects and lowered reactive oxygen species (ROS levels in cells subjected to t-BHP-induced oxidative stress. These effects were accompanied by increased oxygen consumption, suggesting that Amla protected cells against oxidative stress by using enhanced spare respiratory capacity to produce more energy. Thus we identified protective effects of Amla, involving activation of mitochondrial function, which potentially explain its various effects on age-related disorders.

Trapezius muscle activity increases during near work activity regardless of accommodation/vergence demand level.

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Richter, H O; Zetterberg, C; Forsman, M

2015-07-01

To investigate if trapezius muscle activity increases over time during visually demanding near work. The vision task consisted of sustained focusing on a contrast-varying black and white Gabor grating. Sixty-six participants with a median age of 38 (range 19-47) fixated the grating from a distance of 65 cm (1.5 D) during four counterbalanced 7-min periods: binocularly through -3.5 D lenses, and monocularly through -3.5 D, 0 D and +3.5 D. Accommodation, heart rate variability and trapezius muscle activity were recorded in parallel. General estimating equation analyses showed that trapezius muscle activity increased significantly over time in all four lens conditions. A concurrent effect of accommodation response on trapezius muscle activity was observed with the minus lenses irrespective of whether incongruence between accommodation and convergence was present or not. Trapezius muscle activity increased significantly over time during the near work task. The increase in muscle activity over time may be caused by an increased need of mental effort and visual attention to maintain performance during the visual tasks to counteract mental fatigue.

[A case of respiratory dyskinesia due to clebopride malate].

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Kawasaki, H; Yamamoto, M; Okayasu, H; Wakayama, Y

1991-08-01

Clebopride malate is therapeutically used for the treatment of peptic ulcer. This drug has potent antidopaminergic activity that causes acute dystonic reaction, parkinsonism and tardive dyskinesia as adverse effects. Here, we have reported an 86-year-old man who developed abnormal involuntary movement of respiratory muscles and lower limb muscles after this drug had been given for four months. This involuntary movement appeared spontaneously at resting state and disappeared during sleep. Surface EMG demonstrated a synchronous grouping discharge in m. orbicularis oris, m. sternocleidomastoideus and m. interstales which synchronized with diaphragmatic movement on cinefluorography. Involuntary movement of the lower limbs was synchronous bilaterally and had little relationship with diaphragmatic movement. This involuntary movement was irregular not only in rhythm but also in duration. According to this irregular nature, we diagnosed this involuntary movement as respiratory dyskinesia with limb dyskinesia that belongs to tardive dyskinesia. After cessation of clebopride malate limb dyskinesia disappeared rapidly and respiratory dyskinesia markedly decreased. We emphasize that respiratory dyskinesia should be differentiated from psychogenic hyperventilation as easily misdiagnosed on initial examination.

How Insect Flight Steering Muscles Work

OpenAIRE

Walker, Simon M.; Schwyn, Daniel A.; Mokso, Rajmund; Wicklein, Martina; Müller, Tonya; Doube, Michael; Stampanoni, Marco; Krapp, Holger G.; Taylor, Graham K.

2014-01-01

Dipteran flies are amongst the smallest and most agile of flying animals. Their wings are driven indirectly by large power muscles, which cause cyclical deformations of the thorax that are amplified through the intricate wing hinge. Asymmetric flight manoeuvres are controlled by 13 pairs of steering muscles acting directly on the wing articulations. Collectively the steering muscles account for

Dental restorative materials from a work environmental perspective

OpenAIRE

Lönnroth, Emma-Christin

1999-01-01

The main occupational health hazard for dental personnel is muscle-skeletal problem, followed by symptoms caused by exposure to chemicals. Clinical dental work includes exposure to a number of products like soap, detergents, disinfectants, amalgam, mono- and oligomers, catalysts, inhibitors, solvents and adhesives. Some are chemically very active. The aims of this thesis have been to survey the occurrence of symptoms from skin, eyes and respiratory tract among dental personnel working in gene...

Respiratory Failure

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Respiratory failure happens when not enough oxygen passes from your lungs into your blood. Your body's organs, ... brain, need oxygen-rich blood to work well. Respiratory failure also can happen if your lungs can' ...

Respiratory impairment and the aging lung: a novel paradigm for assessing pulmonary function.

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Vaz Fragoso, Carlos A; Gill, Thomas M

2012-03-01

Older persons have an increased risk of developing respiratory impairment because the aging lung is likely to have experienced exposures to environmental toxins as well as reductions in physiological capacity. Systematic review of risk factors and measures of pulmonary function that are most often considered when defining respiratory impairment in aging populations. Across the adult life span, there are frequent exposures to environmental toxins, including tobacco smoke, respiratory infections, air pollution, and occupational dusts. Concurrently, there are reductions in physiological capacity that may adversely affect ventilatory control, respiratory muscle strength, respiratory mechanics, and gas exchange. Recent work has provided a strong rationale for defining respiratory impairment as an age-adjusted reduction in spirometric measures of pulmonary function that are independently associated with adverse health outcomes. Specifically, establishing respiratory impairment based on spirometric Z-scores has been shown to be strongly associated with respiratory symptoms, frailty, and mortality. Alternatively, respiratory impairment may be defined by the peak expiratory flow, as measured by a peak flow meter. The peak expiratory flow, when expressed as a Z-score, has been shown to be strongly associated with disability and mortality. However, because it has a reduced diagnostic accuracy, peak expiratory flow should only define respiratory impairment when spirometry is not readily available or an older person cannot adequately perform spirometry. Aging is associated with an increased risk of developing respiratory impairment, which is best defined by spirometric Z-scores. Alternatively, in selected cases, respiratory impairment may be defined by peak expiratory flow, also expressed as a Z-score.

Can exposure variation be promoted in the shoulder girdle muscles by modifying work pace and inserting pauses during simulated assembly work?

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Januario, Leticia Bergamin; Madeleine, Pascal; Cid, Marina Machado; Samani, Afshin; Oliveira, Ana Beatriz

2018-01-01

This study investigated the acute effects of changing the work pace and implementing two pause types during an assembly task. Eighteen healthy women performed a simulated task in four different conditions: 1) slow or 2) fast work pace with 3) passive or 4) active pauses every two minutes. The root mean square (RMS) and exposure variation analysis (EVA) from the trapezius and serratus anterior muscles, as well as the rate of perceived exertion (RPE) from the neck-shoulder region, were observed. Decreased RMS and RPE as well as more variable muscle activity (EVA) were observed in the slow work pace compared with the fast one. The pause types had a limited effect, but active pauses resulted in increased RMS of the clavicular trapezius. The findings revealed the importance of work pace in the reduction of perceived exertion and promotion of variation in muscle activation during assembly tasks. However, the pause types had no important effect on the evaluated outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Angiotensin II Infusion Induces Marked Diaphragmatic Skeletal Muscle Atrophy

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Rezk, Bashir M.; Yoshida, Tadashi; Semprun-Prieto, Laura; Higashi, Yusuke; Sukhanov, Sergiy; Delafontaine, Patrice

2012-01-01

Advanced congestive heart failure (CHF) and chronic kidney disease (CKD) are characterized by increased angiotensin II (Ang II) levels and are often accompanied by significant skeletal muscle wasting that negatively impacts mortality and morbidity. Both CHF and CKD patients have respiratory muscle dysfunction, however the potential effects of Ang II on respiratory muscles are unknown. We investigated the effects of Ang II on diaphragm muscle in FVB mice. Ang II induced significant diaphragm muscle wasting (18.7±1.6% decrease in weight at one week) and reduction in fiber cross-sectional area. Expression of the E3 ubiquitin ligases atrogin-1 and muscle ring finger-1 (MuRF-1) and of the pro-apoptotic factor BAX was increased after 24 h of Ang II infusion (4.4±0.3 fold, 3.1±0.5 fold and 1.6±0.2 fold, respectively, compared to sham infused control) suggesting increased muscle protein degradation and apoptosis. In Ang II infused animals, there was significant regeneration of injured diaphragm muscles at 7 days as indicated by an increase in the number of myofibers with centralized nuclei and high expression of embryonic myosin heavy chain (E-MyHC, 11.2±3.3 fold increase) and of the satellite cell marker M-cadherin (59.2±22.2% increase). Furthermore, there was an increase in expression of insulin-like growth factor-1 (IGF-1, 1.8±0.3 fold increase) in Ang II infused diaphragm, suggesting the involvement of IGF-1 in diaphragm muscle regeneration. Bone-marrow transplantation experiments indicated that although there was recruitment of bone-marrow derived cells to the injured diaphragm in Ang II infused mice (267.0±74.6% increase), those cells did not express markers of muscle stem cells or regenerating myofibers. In conclusion, Ang II causes marked diaphragm muscle wasting, which may be important for the pathophysiology of respiratory muscle dysfunction and cachexia in conditions such as CHF and CKD. PMID:22276172

Angiotensin II infusion induces marked diaphragmatic skeletal muscle atrophy.

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Bashir M Rezk

Full Text Available Advanced congestive heart failure (CHF and chronic kidney disease (CKD are characterized by increased angiotensin II (Ang II levels and are often accompanied by significant skeletal muscle wasting that negatively impacts mortality and morbidity. Both CHF and CKD patients have respiratory muscle dysfunction, however the potential effects of Ang II on respiratory muscles are unknown. We investigated the effects of Ang II on diaphragm muscle in FVB mice. Ang II induced significant diaphragm muscle wasting (18.7±1.6% decrease in weight at one week and reduction in fiber cross-sectional area. Expression of the E3 ubiquitin ligases atrogin-1 and muscle ring finger-1 (MuRF-1 and of the pro-apoptotic factor BAX was increased after 24 h of Ang II infusion (4.4±0.3 fold, 3.1±0.5 fold and 1.6±0.2 fold, respectively, compared to sham infused control suggesting increased muscle protein degradation and apoptosis. In Ang II infused animals, there was significant regeneration of injured diaphragm muscles at 7 days as indicated by an increase in the number of myofibers with centralized nuclei and high expression of embryonic myosin heavy chain (E-MyHC, 11.2±3.3 fold increase and of the satellite cell marker M-cadherin (59.2±22.2% increase. Furthermore, there was an increase in expression of insulin-like growth factor-1 (IGF-1, 1.8±0.3 fold increase in Ang II infused diaphragm, suggesting the involvement of IGF-1 in diaphragm muscle regeneration. Bone-marrow transplantation experiments indicated that although there was recruitment of bone-marrow derived cells to the injured diaphragm in Ang II infused mice (267.0±74.6% increase, those cells did not express markers of muscle stem cells or regenerating myofibers. In conclusion, Ang II causes marked diaphragm muscle wasting, which may be important for the pathophysiology of respiratory muscle dysfunction and cachexia in conditions such as CHF and CKD.

Myosin phosphorylation potentiates steady-state work output without altering contractile economy of mouse fast skeletal muscles.

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Gittings, William; Bunda, Jordan; Vandenboom, Rene

2018-01-30

Skeletal myosin light chain kinase (skMLCK)-catalyzed phosphorylation of the myosin regulatory light chain (RLC) increases (i.e. potentiates) mechanical work output of fast skeletal muscle. The influence of this event on contractile economy (i.e. energy cost/work performed) remains controversial, however. Our purpose was to quantify contractile economy of potentiated extensor digitorum longus (EDL) muscles from mouse skeletal muscles with (wild-type, WT) and without (skMLCK ablated, skMLCK -/- ) the ability to phosphorylate the RLC. Contractile economy was calculated as the ratio of total work performed to high-energy phosphate consumption (HEPC) during a period of repeated isovelocity contractions that followed a potentiating stimulus (PS). Consistent with genotype, the PS increased RLC phosphorylation measured during, before and after isovelocity contractions in WT but not in skMLCK -/- muscles (i.e. 0.65 and 0.05 mol phosphate mol -1 RLC, respectively). In addition, although the PS enhanced work during repeated isovelocity contractions in both genotypes, the increase was significantly greater in WT than in skMLCK -/- muscles (1.51±0.03 versus 1.10±0.05, respectively; all data P economy calculated for WT muscles was similar to that calculated for skMLCK -/- muscles (i.e. 5.74±0.67 and 4.61±0.71 J kg -1  μmol -1 P, respectively ( P economy. © 2018. Published by The Company of Biologists Ltd.

Respiratory muscle strength and pulmonary function in children with rhinitis and asthma after a six-minute walk test.

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Soares, Ana Alice de Almeida; Barros, Camila Moraes; Santos, Cássia Giulliane Costa; Dos Santos, Maria Renata Aragão; Silva, José Rodrigo Santos; Silva Junior, Walderi Monteiro da; Simões, Silvia de Magalhães

2018-03-01

Rhinitis and asthma decrease quality of life. Few studies have assessed the performance of children with asthma or rhinitis under submaximal exercise. We evaluated maximal respiratory pressures, spirometric parameters, and ability to sustain submaximal exercise in these children before and after the 6-minute walk test (6MWT), compared to healthy children. This cross-sectional, analytical study included 89 children aged 6-12 years in outpatient follow-up: 27 healthy (H), 31 with rhinitis (R), and 31 with mild asthma under control (A). Pulmonary function parameters and maximal respiratory pressures were measured before and 5, 10, and 30 minutes after the 6MWT. Wilcoxon test was used to compare numerical numerical variables between two groups and analysis of variance or Kruskal-Wallis test for comparison among three groups. Total distance traveled in the 6MWT was similar among the three groups. Compared to pre-test values, VEF1 (Forced Expiratory Volume in 1 second), VEF0.75 (Forced Expiratory Volume in 0.75 second), and FEF25-75 (Forced Expiratory Flow 25-75% of the Forced Vital Capacity - CVF - curve) decreased significantly after the 6MWT in group A, and VEF0.75, FEF25-75, and VEF1/CVF decreased significantly in group R. Groups A and R had lower Maximum Inspiratory Pressure values than group H before and after the 6MWT at all time points assessed. The findings suggest that children with rhinitis and mild asthma present with alterations in respiratory muscle strength and pulmonary function not associated with clinical complaints, reinforcing the concept of the united airways.

Residual curarization and postoperative respiratory complications following laparoscopic sleeve gastrectomy. The effect of reversal agents: sugammadex vs. neostigmine

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Ezri Tiberiu

2015-04-01

Full Text Available Background: Incomplete muscle relaxant reversal or re-curarization may be associated with postoperative respiratory complications. In this retrospective study we compared the incidence of postoperative residual curarization and respiratory complications in association with the type of muscle relaxant reversal agent, sugammadex or neostigmine, in patients undergoing laparoscopic sleeve gastrectomy.

Muscle glycogen depletion patterns during draught work in Standardbred horses.

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Gottlieb, M

1989-03-01

Muscle fibre recruitment was investigated during draught loaded exercise by studying glycogen depletion patterns from histochemical stains of muscle biopsies from the gluteus and semitendinosus muscles. Three Standardbred trotters performed several intervals of draught loaded exercise on a treadmill with 34 kp at a trot (7 m/sec) and with 34 and 80 kp, respectively at a walk (2m/sec). Exercise was continued until the horses were unwilling to continue. Glycogen depletion was seen in all three fibre types when trotting with 34 kp for 5 or 10 mins. When an equal weight resistance was pulled at a walk, glycogen depletion was first seen in type I fibres only, then followed by a small percentage of type IIA fibres after at least 1 h. When 80 kp was pulled at a walk both type I and IIA fibres showed glycogen depletion, and after at least 30 mins exercise a small percentage of type IIB fibres was also depleted. These results indicate that the muscle fibres are depleted, in order, from type I through IIA to IIB as the intensity or duration of draught work increases.

The influence of altered working-side occlusal guidance on masticatory muscles and related jaw movement.

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Belser, U C; Hannam, A G

1985-03-01

The effect of four different occlusal situations (group function, canine guidance, working side occlusal interference, and hyperbalancing occlusal interference) on EMG activity in jaw elevator muscles and related mandibular movement was investigated on 12 subjects. With a computer-based system, EMG and displacement signals were collected simultaneously during specific functional (unilateral chewing) and parafunctional tasks (mandibular gliding movements and various tooth clenching efforts) and analyzed quantitatively. When a naturally acquired group function was temporarily and artificially changed into a dominant canine guidance, a significant general reduction of elevator muscle activity was observed when subjects exerted full isometric tooth-clenching efforts in a lateral mandibular position. The original muscular coordination pattern (relative contraction from muscle to muscle) remained unaltered during this test. With respect to unilateral chewing, no significant alterations in the activity or coordination of the muscles occurred when an artificial canine guidance was introduced. Introduction of a hyperbalancing occlusal contact caused significant alterations in muscle activity and coordination during maximal tooth clenching in a lateral mandibular position. A marked shift of temporal muscle EMG activity toward the side of the interference and unchanged bilateral activity of the two masseter muscles were observed. The results suggest that canine-protected occlusions do not significantly alter muscle activity during mastication but significantly reduce muscle activity during parafunctional clenching. They also suggest that non-working side contacts dramatically alter the distribution of muscle activity during parafunctional clenching, and that this redistribution may affect the nature of reaction forces at the temporomandibular joints.

Memories of early work on muscle contraction and regulation in the 1950's and 1960's

International Nuclear Information System (INIS)

Huxley, Hugh E.

2008-01-01

Professor Ebashi's epic work on the biochemistry of the regulation of muscle contraction began in the early 1950's, during the same period that work on the molecular basis of force production in muscle was also beginning. The latter work started in two MRC Research Units in the UK, and was continued jointly by the two workers from those Units who had, independently, gone to MIT to learn the new techniques of electron microscopy and to apply them to muscle. In a somewhat similar fashion, Professor Ebashi also spent one or two years in the USA, continuing his work on the role of calcium in muscle regulation in Lippman's laboratory, before returning to Japan to achieve the great breakthroughs in this work during the 1960's. Hanson and Huxley, after putting forward the overlapping actin and myosin filament arrays model for the striated muscle sarcomere, and subsequently the sliding filament model of muscle contraction (simultaneously with A.F Huxley and R. Niedergerke), returned to the UK to pursue detailed structural studies in separate Research Units, in a mixture of consultation, collaboration, and competition, during the later 1950's and throughout the 1960's. However, the path to enlightenment described here in some detail was somewhat more tortuous than the standard literature perhaps reveals. Nevertheless, by the time of the Cold Spring Harbor Symposium on Muscle Contraction in 1972, the two lines of enquiry on regulation itself, and on the tilting cross-bridge model of force production, had arrived at a good deal of common ground, and indeed the identification of troponin and its periodic distribution along the actin filaments had helped resolve a long-standing puzzle in the interpretation of the low angle X-ray diagram. Since then, an enormous amount of remarkable new work has been necessary to establish troponin regulation and the tilting cross-bridge mechanism in molecular detail, but the work in the 1950's and 1960's has provided a firm and accurate basis

Noninvasive Respiratory Management of Patients With Neuromuscular Disease.

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Bach, John R

2017-08-01

This review article describes definitive noninvasive respiratory management of respiratory muscle dysfunction to eliminate need to resort to tracheotomy. In 2010 clinicians from 22 centers in 18 countries reported 1,623 spinal muscular atrophy type 1 (SMA1), Duchenne muscular dystrophy (DMD), and amyotrophic lateral sclerosis users of noninvasive ventilatory support (NVS) of whom 760 required it continuously (CNVS). The CNVS sustained their lives by over 3,000 patient-years without resort to indwelling tracheostomy tubes. These centers have now extubated at least 74 consecutive ventilator unweanable patients with DMD, over 95% of CNVS-dependent patients with SMA1, and hundreds of others with advanced neuromuscular disorders (NMDs) without resort to tracheotomy. Two centers reported a 99% success rate at extubating 258 ventilator unweanable patients without resort to tracheotomy. Patients with myopathic or lower motor neuron disorders can be managed noninvasively by up to CNVS, indefinitely, despite having little or no measurable vital capacity, with the use of physical medicine respiratory muscle aids. Ventilator-dependent patients can be decannulated of their tracheostomy tubes.

Practical approach to management of respiratory complications in neurological disorders

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Mangera Z

2012-03-01

Full Text Available Zaheer Mangera, Kirat Panesar, Himender MakkerRespiratory Medicine, North Middlesex University Hospital, London, UKAbstract: Patients with certain neurological diseases are at increased risk of developing chest infections as well as respiratory failure due to muscular weakness. In particular, patients with certain neuromuscular disorders are at higher risk. These conditions are often associated with sleep disordered breathing. It is important to identify patients at risk of respiratory complications early in the course of their disease, although patients with neuromuscular disorders often present in the acute setting with respiratory involvement. This review of the respiratory complications of neurological disorders, with a particular focus on neuromuscular disorders, explores why this happens and looks at how to recognize, investigate, and manage these patients effectively.Keywords: respiratory failure, respiratory muscle weakness

Regulation of skeletal muscle oxidative capacity and muscle mass by SIRT3.

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Ligen Lin

Full Text Available We have previously reported that the expression of mitochondrial deacetylase SIRT3 is high in the slow oxidative muscle and that the expression of muscle SIRT3 level is increased by dietary restriction or exercise training. To explore the function of SIRT3 in skeletal muscle, we report here the establishment of a transgenic mouse model with muscle-specific expression of the murine SIRT3 short isoform (SIRT3M3. Calorimetry study revealed that the transgenic mice had increased energy expenditure and lower respiratory exchange rate (RER, indicating a shift towards lipid oxidation for fuel usage, compared to control mice. The transgenic mice exhibited better exercise performance on treadmills, running 45% further than control animals. Moreover, the transgenic mice displayed higher proportion of slow oxidative muscle fibers, with increased muscle AMPK activation and PPARδ expression, both of which are known regulators promoting type I muscle fiber specification. Surprisingly, transgenic expression of SIRT3M3 reduced muscle mass up to 30%, likely through an up-regulation of FOXO1 transcription factor and its downstream atrophy gene MuRF-1. In summary, these results suggest that SIRT3 regulates the formation of oxidative muscle fiber, improves muscle metabolic function, and reduces muscle mass, changes that mimic the effects of caloric restriction.

[Two patients with mitochondrial respiratory chain disease].

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Bangma, H R; Smit, G P A; Kuks, J B M; Grevink, R G; Wolffenbuttel, B H R

2008-10-18

A 23-year-old woman and a 13-year-old boy were diagnosed with mitochondrial respiratory chain disease. The woman had muscle pain, fatigue and bilateral ophthalmoplegia--symptoms consistent with Kearns-Sayre syndrome. The boy had aspecific symptoms; eventually, reduced activity of complex 1 was found to be the cause of the mitochondrial respiratory chain disease in the boy and his mother, who had suffered from unexplained fatigue and muscle pain for 15 years. Mitochondrial diseases often involve several organ systems. Diagnosis can be difficult, because laboratory tests such as serum and urinary lactate and creatine kinase have low sensitivity and specificity. Biochemical assessment of muscle biopsy can reveal reduced oxidation ATP synthesis and sometimes specific abnormalities in individual protein complexes. DNA analysis may be helpful in demonstrating mitochondrial or nuclear mutations or deletions. The goal of treatment is to increase mitochondrial ATP production, improve clinical symptoms and enhance stamina. Replacement of the following substances (also referred to as cofactors) may be attempted: co-enzyme Q10, antioxidants (lipoic acid, vitamins C and E), riboflavin, thiamine, creatine and carnitine. Evidence regarding the optimal treatment approach is lacking; one usually has to rely on observing effects in the individual patient.

Rib cage deformities alter respiratory muscle action and chest wall function in patients with severe osteogenesis imperfecta.

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Antonella LoMauro

Full Text Available BACKGROUND: Osteogenesis imperfecta (OI is an inherited connective tissue disorder characterized by bone fragility, multiple fractures and significant chest wall deformities. Cardiopulmonary insufficiency is the leading cause of death in these patients. METHODS: Seven patients with severe OI type III, 15 with moderate OI type IV and 26 healthy subjects were studied. In addition to standard spirometry, rib cage geometry, breathing pattern and regional chest wall volume changes at rest in seated and supine position were assessed by opto-electronic plethysmography to investigate if structural modifications of the rib cage in OI have consequences on ventilatory pattern. One-way or two-way analysis of variance was performed to compare the results between the three groups and the two postures. RESULTS: Both OI type III and IV patients showed reduced FVC and FEV(1 compared to predicted values, on condition that updated reference equations are considered. In both positions, ventilation was lower in OI patients than control because of lower tidal volume (p<0.01. In contrast to OI type IV patients, whose chest wall geometry and function was normal, OI type III patients were characterized by reduced (p<0.01 angle at the sternum (pectus carinatum, paradoxical inspiratory inward motion of the pulmonary rib cage, significant thoraco-abdominal asynchronies and rib cage distortions in supine position (p<0.001. CONCLUSIONS: In conclusion, the restrictive respiratory pattern of Osteogenesis Imperfecta is closely related to the severity of the disease and to the sternal deformities. Pectus carinatum characterizes OI type III patients and alters respiratory muscles coordination, leading to chest wall and rib cage distortions and an inefficient ventilator pattern. OI type IV is characterized by lower alterations in the respiratory function. These findings suggest that functional assessment and treatment of OI should be differentiated in these two forms of the

[Management and treatment of respiratory failure associated with amyotrophic lateral sclerosis].

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Danel-Brunaud, V; Perez, T; Just, N; Destée, A

2005-04-01

In amyotrophic lateral sclerosis (ALS), respiratory muscle involvement is highly predictive of survival and quality of life (QOL). There is compelling evidence that non invasive ventilation (NIV) prolongs survival by several months and improves QOL more than any other currently available treatment. Frequent testing of pulmonary function and regular evaluations are recommended since 1999 by the American Academy of Neurology in order to take appropriate treatment decisions. There are numerous tests available to evaluate respiratory status in ALS and it is important to know their sensitivity and specificity to recognize clinical risk situations. Some recent data suggest that sniff nasal pressure and maximal inspiratory pressure (MIP) can be performed reliably by most ALS patients and are more sensitive to decrements in inspiratory muscle strength than spirometry or arterial blood gasometry. Airway obstruction caused by ineffective coughing is the principal cause of intolerance to NIV. Several factors other than respiratory muscle strength may affect pulmonary function: postural changes, nutritional status, infectious disease, drugs. The neurologist has to coordinate multidisciplinary care, with attention to individual patient preferences, and with a frank and compassionate discussion between the patient, the family, the physicians and the caregivers.

Repeated static contractions increase mitochondrial vulnerability toward oxidative stress in human skeletal muscle

DEFF Research Database (Denmark)

Sahlin, Kent; Nielsen, Jens Steen; Mogensen, Martin

2006-01-01

Repeated static contractions (RSC) induce large fluctuations in tissue oxygen tension and increase the generation of reactive oxygen species (ROS). This study investigated the effect of RSC on muscle contractility, mitochondrial respiratory function, and in vitro sarcoplasmic reticulum (SR) Ca(2......+) kinetics in human muscle. Ten male subjects performed five bouts of static knee extension with 10-min rest in between. Each bout of RSC (target torque 66% of maximal voluntary contraction torque) was maintained to fatigue. Muscle biopsies were taken preexercise and 0.3 and 24 h postexercise from vastus...... lateralis. Mitochondria were isolated and respiratory function measured after incubation with H(2)O(2) (HPX) or control medium (Con). Mitochondrial function was not affected by RSC during Con. However, RSC exacerbated mitochondrial dysfunction during HPX, resulting in decreased respiratory control index...

Responses of algesic and metabolic substances to 8h of repetitive manual work in myalgic human trapezius muscle

DEFF Research Database (Denmark)

Larsson, B.; Rosendal, L.; Kristiansen, J.

2008-01-01

The trapezius muscle often develops pain as the result of repetitive and stressful work tasks although it is unclear to what extent this pain is due to alterations in muscle concentrations of algesic/nociceptive substances. Twenty women with chronic neck- and shoulder pain (TM) whose work required...... highly repetitive work tasks and 20 pain-free female colleagues (CON) were studied during and after a full 8-hour workday. We collected microdialysates from their dominant/most painful trapezius muscle; concentrations of serotonin, glutamate, lactate, pyruvate, potassium, bradykinin, and cytokines...... muscles. TM had higher concentrations of glutamate (71+/-42 vs. 36+/-15mumoll(-1)) and pyruvate (187+/-89 vs. 125+/-63mumoll(-1)) than CON. Interstitial serotonin was higher in TM (before work: 10.6+/-10.8 vs. 2.2+/-1.2nM; after work: 9.2+/-8.3 vs. 1.5+/-2.9nM). The trapezius blood flow during the working...

Exercise training and work task induced metabolic and stress-related mRNA and protein responses in myalgic muscles

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Sjøgaard, Gisela; Zebis, Mette Kreutzfeldt; Kiilerich, Kristian

2013-01-01

healthy controls. Those with myalgia performed similar to 7 hrs repetitive stressful work and were subsequently randomized to 10 weeks of specific strength training, general fitness training, or reference intervention. Muscles biopsies were taken from the trapezius muscle at baseline, after work and after...... 10 weeks intervention. The main findings are that the capacity of carbohydrate oxidation was reduced in myalgic compared with healthy muscle. Repetitive stressful work increased mRNA content for heat shock proteins and decreased levels of key regulators for growth and oxidative metabolism......The aim was to assess mRNA and/or protein levels of heat shock proteins, cytokines, growth regulating, and metabolic proteins in myalgic muscle at rest and in response to work tasks and prolonged exercise training. A randomized controlled trial included 28 females with trapezius myalgia and 16...

On the respiratory flow in the cuttlefish sepia officinalis.

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Bone, Q; Brown, E; Travers, G

1994-09-01

The respiratory flow of water over the gills of the cuttlefish Sepia officinalis at rest is produced by the alternate activity of the radial muscles of the mantle and the musculature of the collar flaps; mantle circular muscle fibres are not involved. Inspiration takes place as the radial fibres contract, thinning the mantle and expanding the mantle cavity. The rise in mantle cavity pressure (up to 0.15 kPa), expelling water via the siphon during expiration, is brought about by inward movement of the collar flaps and (probably) mainly by elastic recoil of the mantle connective tissue network 'wound up' by radial fibre contraction during inspiration. Sepia also shows a second respiratory pattern, in which mantle cavity pressures during expiration are greater (up to 0.25 kPa). Here, the mantle circular fibres are involved, as they are during the large pressure transients (up to 10 kPa) seen during escape jetting. Active contraction of the muscles of the collar flaps is seen in all three patterns of expulsion of water from the mantle cavity, electrical activity increasing with increasing mantle cavity pressures. Respiratory expiration in the resting squid Loligo vulgaris is probably driven as in Sepia, whereas in the resting octopus Eledone cirrhosa, the mantle circular musculature is active during expiration. The significance of these observations is discussed.

Effects of acute respiratory and metabolic acidosis on diaphragm muscle obtained from rats.

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Michelet, Pierre; Carreira, Serge; Demoule, Alexandre; Amour, Julien; Langeron, Olivier; Riou, Bruno; Coirault, Catherine

2015-04-01

Acute respiratory acidosis is associated with alterations in diaphragm performance. The authors compared the effects of respiratory acidosis and metabolic acidosis in the rat diaphragm in vitro. Diaphragmatic strips were stimulated in vitro, and mechanical and energetic variables were measured, cross-bridge kinetics calculated, and the effects of fatigue evaluated. An extracellular pH of 7.00 was obtained by increasing carbon dioxide tension (from 25 to 104 mmHg) in the respiratory acidosis group (n = 12) or lowering bicarbonate concentration (from 24.5 to 5.5 mM) in the metabolic acidosis group (n = 12) and the results compared with a control group (n = 12, pH = 7.40) after 20-min exposure. Respiratory acidosis induced a significant decrease in maximum shortening velocity (-33%, P Respiratory acidosis impaired more relaxation than contraction, as shown by impairment in contraction-relaxation coupling under isotonic (-26%, P acidosis group. In rat diaphragm, acute (20 min) respiratory acidosis induced a marked decrease in the diaphragm contractility, which was not observed in metabolic acidosis.

Role of skeletal muscle in lung development.

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Baguma-Nibasheka, Mark; Gugic, Dijana; Saraga-Babic, Mirna; Kablar, Boris

2012-07-01

Skeletal (striated) muscle is one of the four basic tissue types, together with the epithelium, connective and nervous tissues. Lungs, on the other hand, develop from the foregut and among various cell types contain smooth, but not skeletal muscle. Therefore, during earlier stages of development, it is unlikely that skeletal muscle and lung depend on each other. However, during the later stages of development, respiratory muscle, primarily the diaphragm and the intercostal muscles, execute so called fetal breathing-like movements (FBMs), that are essential for lung growth and cell differentiation. In fact, the absence of FBMs results in pulmonary hypoplasia, the most common cause of death in the first week of human neonatal life. Most knowledge on this topic arises from in vivo experiments on larger animals and from various in vitro experiments. In the current era of mouse mutagenesis and functional genomics, it was our goal to develop a mouse model for pulmonary hypoplasia. We employed various genetically engineered mice lacking different groups of respiratory muscles or lacking all the skeletal muscle and established the criteria for pulmonary hypoplasia in mice, and therefore established a mouse model for this disease. We followed up this discovery with systematic subtractive microarray analysis approach and revealed novel functions in lung development and disease for several molecules. We believe that our approach combines elements of both in vivo and in vitro approaches and allows us to study the function of a series of molecules in the context of lung development and disease and, simultaneously, in the context of lung's dependence on skeletal muscle-executed FBMs.

Cardio-respiratory response of young adult Indian male subjects to stress: Effects of progressive muscle relaxation

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Arunima Chaudhuri

2014-01-01

Full Text Available Background: Stress and anxiety have become an integral part of our lives. Of late, this has resulted in the increase in incidence of hypertension and coronary heart disease. Objectives: To assess the effect of progressive muscle relaxation (PMR on young adult males and its role in the modulation of cardio-respiratory response on exposure to stress. Materials and Methods: This prospective cross-sectional study was conducted in a tertiary care referral hospital. Undergraduate male students under stress were chosen for the study. Fasting blood samples were drawn to analyze sugar and lipid profile, followed by anthropometric measurements and ECG. In the resting condition, blood pressure, pulse rate, and spirometric parameters; forced vital capacities (FVC, and forced expiratory volume in 1 sec (FEV 1 % were measured. Then, they were made to exercise with bicycle ergometer and post exercise, the vital parameters were recorded. All subjects were given a training of Jacobson′s Progressive Muscular Relaxation and asked to practice this technique for 3 months. All parameters were re-evaluated. Results: Significant decreases in resting heart rate, systolic blood pressure and diastolic blood pressure, total cholesterol, triglyceride, and low density lipoprotein (LDL cholesterol levels of subjects were seen after PMR training. Exercise-induced rise in heart rate and blood pressure were also significantly less in subjects following PMR training. Conclusion: Progressive muscle relaxation helps in modulation of heart rate, blood pressure, and lipid profile in healthy normal adult male individuals.

Termination of respiratory events with and without cortical arousal in obstructive sleep apnea.

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Jordan, Amy S; Eckert, Danny J; Wellman, Andrew; Trinder, John A; Malhotra, Atul; White, David P

2011-11-15

A total of 20-30% of respiratory events in obstructive sleep apnea are terminated without clear arousal. Arousals are thought to predispose to further events by promoting hyperventilation, hypocapnia, and upper-airway dilator muscle hypotonia. Therefore, events terminated without arousal may promote stable breathing. To compare physiologic changes at respiratory event termination with American Sleep Disorders Association (ASDA) Arousal to No Arousal, and determine whether secondary respiratory events are less common and have higher dilator muscle activity after No Arousal compared with ASDA Arousal. Patients with obstructive sleep apnea wore sleep staging, genioglossus (EMG(GG)), and tensor palatini (EMG(TP)) electrodes plus a nasal mask and pneumotachograph. During stable sleep, continuous positive airway pressure (CPAP) was lowered for 3-minute periods to induce respiratory events. Physiologic variables were compared between events terminated with (1) ASDA Arousal, (2) No Arousal, or (3) sudden CPAP increase (CPAPinc, control). Sixteen subjects had adequate data. EMG(GG), EMG(TP), and heart rate increased after ASDA Arousal (340 ± 57%, 215 ± 28%, and 110.7 ± 2.3%) and No Arousal (185 ± 32%, 167 ± 15%, and 108.5 ± 1.6%) but not CPAPinc (90 ± 10%, 94 ± 11%, and 102.1 ± 1%). Ventilation increased more after ASDA Arousal than No Arousal and CPAPinc, but not after accounting for the severity of respiratory event. Fewer No Arousals were followed by secondary events than ASDA Arousals. However, low dilator muscle activity did not occur after ASDA Arousal or No Arousal (EMG(GG) rose from 75 ± 5 to 125 ± 7%) and secondary events were less severe than initial events (ventilation rose 4 ± 0.4 to 5.5 ± 0.51 L/min). Respiratory events that were terminated with ASDA Arousal were more severely flow-limited, had enhanced hyperventilation after event termination, and were more often followed by secondary events than No arousal. However, secondary events were not

Lipid-storage myopathy and respiratory insufficiency due to ETFQO mutations in a patient with late-onset multiple acyl-CoA dehydrogenation deficiency

DEFF Research Database (Denmark)

Olsen, Rikke Katrine Jentoft; Pourfarzam, M; Morris, A A M

2004-01-01

response to treatment, she developed respiratory insufficiency at age 14 years and has required long-term overnight ventilation. Thus, MADD is one of the few conditions that can cause a myopathy with weakness of the respiratory muscles out of proportion to the limb muscles. Udgivelsesdato: 2004-null...

Respiration-related discharge of hyoglossus muscle motor units in the rat.

Science.gov (United States)

Powell, Gregory L; Rice, Amber; Bennett-Cross, Seres J; Fregosi, Ralph F

2014-01-01

Although respiratory muscle motor units have been studied during natural breathing, simultaneous measures of muscle force have never been obtained. Tongue retractor muscles, such as the hyoglossus (HG), play an important role in swallowing, licking, chewing, breathing, and, in humans, speech. The HG is phasically recruited during the inspiratory phase of the respiratory cycle. Moreover, in urethane anesthetized rats the drive to the HG waxes and wanes spontaneously, providing a unique opportunity to study motor unit firing patterns as the muscle is driven naturally by the central pattern generator for breathing. We recorded tongue retraction force, the whole HG muscle EMG and the activity of 38 HG motor units in spontaneously breathing anesthetized rats under low-force and high-force conditions. Activity in all cases was confined to the inspiratory phase of the respiratory cycle. Changes in the EMG were correlated significantly with corresponding changes in force, with the change in EMG able to predict 53-68% of the force variation. Mean and peak motor unit firing rates were greater under high-force conditions, although the magnitude of discharge rate modulation varied widely across the population. Changes in mean and peak firing rates were significantly correlated with the corresponding changes in force, but the correlations were weak (r(2) = 0.27 and 0.25, respectively). These data indicate that, during spontaneous breathing, recruitment of HG motor units plays a critical role in the control of muscle force, with firing rate modulation playing an important but lesser role.

Severe Respiratory Failure in the Coexistence of Polymyositis and Hypothyroidism: A Case Report

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Fatih Yildiz

2013-08-01

Full Text Available Polymyositis is a systemic, inflammatory muscle disease. Respiratory insufficiency as a result of respiratory muscle involvement could also be observed. Here we report a fortyone-year-old man who attended to the hospital with the complaints of shortness of breath and chest pain that have suddenly started. Physical examination has revealed proximal muscle weakness. Serum creatinine phosphokinase level has increased, ANA was positive and the electromyographic examination has revealed myopathic changes. Deltoid muscle biopsy was in accordance with polymyositis. Methyl-prednisolone 1 gram iv pulse therapy was given during the first 5 days. He was started with 25 mg/week parenteral methotrexate. Laboratory tests suggested hypothyroidism and levothyroxine replacement therapy was started. The clinical findings have improved concomitant with the reduction in the muscle enzymes and thyroid stimulant hormone levels into the normal ranges. He was discharged with the recommendation of the NIMV device application during night-time. The clinical symptoms are more severe in the presence of alveolar hypoventilation due to polymyositis and coincidantal hypothyroidism. [Cukurova Med J 2013; 38(4.000: 744-750

Fires. A Joint Publication for U.S. Artillery Professionals. November - December 2009

Science.gov (United States)

2009-11-01

called respiratory alkalosis . If the pH is low, the blood is more acidic. Respiratory alkalosis . Respiratory alkalosis helps offset hypo- baric... Respiratory alkalosis allows more oxygen to be carried to working tissue such as muscle to fuel work. However, respiratory alkalosis also makes unload...ing oxygen to working muscle more difficult. Eventually, the hypoxic drive (the need for oxygen) overrides respiratory alkalosis due to the

Extrapulmonary features of bronchiectasis: muscle function, exercise capacity, fatigue, and health status

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Ozalp Ozge

2012-06-01

Full Text Available Abstract Background There are limited number of studies investigating extrapulmonary manifestations of bronchiectasis. The purpose of this study was to compare peripheral muscle function, exercise capacity, fatigue, and health status between patients with bronchiectasis and healthy subjects in order to provide documented differences in these characteristics for individuals with and without bronchiectasis. Methods Twenty patients with bronchiectasis (43.5 ± 14.1 years and 20 healthy subjects (43.0 ± 10.9 years participated in the study. Pulmonary function, respiratory muscle strength (maximal expiratory pressure – MIP - and maximal expiratory pressure - MEP, and dyspnea perception using the Modified Medical Research Council Dyspnea Scale (MMRC were determined. A six-minute walk test (6MWT was performed. Quadriceps muscle, shoulder abductor, and hand grip strength (QMS, SAS, and HGS, respectively using a hand held dynamometer and peripheral muscle endurance by a squat test were measured. Fatigue perception and health status were determined using the Fatigue Severity Scale (FSS and the Leicester Cough Questionnaire (LCQ, respectively. Results Number of squats, 6MWT distance, and LCQ scores as well as lung function testing values and respiratory muscle strength were significantly lower and MMRC and FSS scores were significantly higher in patients with bronchiectasis than those of healthy subjects (p p p p p  Conclusions Peripheral muscle endurance, exercise capacity, fatigue and health status were adversely affected by the presence of bronchiectasis. Fatigue was associated with dyspnea and health status. Respiratory muscle strength was related to peripheral muscle strength and health status, but not to fatigue, peripheral muscle endurance or exercise capacity. These findings may provide insight for outcome measures for pulmonary rehabilitation programs for patients with bronchiectasis.

Role of the medial medullary reticular formation in relaying vestibular signals to the diaphragm and abdominal muscles

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Mori, R. L.; Bergsman, A. E.; Holmes, M. J.; Yates, B. J.

2001-01-01

Changes in posture can affect the resting length of respiratory muscles, requiring alterations in the activity of these muscles if ventilation is to be unaffected. Recent studies have shown that the vestibular system contributes to altering respiratory muscle activity during movement and changes in posture. Furthermore, anatomical studies have demonstrated that many bulbospinal neurons in the medial medullary reticular formation (MRF) provide inputs to phrenic and abdominal motoneurons; because this region of the reticular formation receives substantial vestibular and other movement-related input, it seems likely that medial medullary reticulospinal neurons could adjust the activity of respiratory motoneurons during postural alterations. The objective of the present study was to determine whether functional lesions of the MRF affect inspiratory and expiratory muscle responses to activation of the vestibular system. Lidocaine or muscimol injections into the MRF produced a large increase in diaphragm and abdominal muscle responses to vestibular stimulation. These vestibulo-respiratory responses were eliminated following subsequent chemical blockade of descending pathways in the lateral medulla. However, inactivation of pathways coursing through the lateral medulla eliminated excitatory, but not inhibitory, components of vestibulo-respiratory responses. The simplest explanation for these data is that MRF neurons that receive input from the vestibular nuclei make inhibitory connections with diaphragm and abdominal motoneurons, whereas a pathway that courses laterally in the caudal medulla provides excitatory vestibular inputs to these motoneurons.

Targeted overexpression of mitochondrial catalase protects against cancer chemotherapy-induced skeletal muscle dysfunction.

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Gilliam, Laura A A; Lark, Daniel S; Reese, Lauren R; Torres, Maria J; Ryan, Terence E; Lin, Chien-Te; Cathey, Brook L; Neufer, P Darrell

2016-08-01

The loss of strength in combination with constant fatigue is a burden on cancer patients undergoing chemotherapy. Doxorubicin, a standard chemotherapy drug used in the clinic, causes skeletal muscle dysfunction and increases mitochondrial H2O2 We hypothesized that the combined effect of cancer and chemotherapy in an immunocompetent breast cancer mouse model (E0771) would compromise skeletal muscle mitochondrial respiratory function, leading to an increase in H2O2-emitting potential and impaired muscle function. Here, we demonstrate that cancer chemotherapy decreases mitochondrial respiratory capacity supported with complex I (pyruvate/glutamate/malate) and complex II (succinate) substrates. Mitochondrial H2O2-emitting potential was altered in skeletal muscle, and global protein oxidation was elevated with cancer chemotherapy. Muscle contractile function was impaired following exposure to cancer chemotherapy. Genetically engineering the overexpression of catalase in mitochondria of muscle attenuated mitochondrial H2O2 emission and protein oxidation, preserving mitochondrial and whole muscle function despite cancer chemotherapy. These findings suggest mitochondrial oxidants as a mediator of cancer chemotherapy-induced skeletal muscle dysfunction. Copyright © 2016 the American Physiological Society.

Circulatory and muscle metabolic responses to draught work compared to increasing trotting velocities.

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Gottlieb, M; Essén-Gustavsson, B; Lindholm, A; Persson, S G

1988-11-01

Circulatory and muscle metabolic responses were studied in 10 horses which all performed incremental draught work at a low trotting speed on a treadmill (D-test) and also exercise with gradually increasing velocities (S-test). Exercise was continued until the horses could no longer maintain the weights above the floor or maintain speed trotting without changing gait to a gallop. Muscle biopsies were taken from the gluteus and the semitendinosus muscles before, and immediately after, exercise. The heart rate (HR) increased linearly with both increasing draught resistance and velocity and reached mean values of 212 and 203 beats/min, respectively. Blood lactate levels increased exponentially to mean values of 12.9 and 7.9 mmol/litre in the two tests. Both HR and blood lactate levels were significantly higher at the cessation of work in the D-test compared to the S-test. The relationship between HR and blood lactate response in the S-test was similar to that in the D-test. The red cell volume was determined after a standardised exercise tolerance test and was significantly correlated both to the weightloading and to the velocity, producing a HR of 200 beats/min. The changes seen in muscle glycogen and glucose-6-phosphate were similar in the two tests, whereas significantly higher lactate levels and lower creatine phosphate and adenosine triphosphate levels were seen in the D-test compared to the S-test. It was concluded that high oxidative capacity is of importance both for fast trotting and for draught work.(ABSTRACT TRUNCATED AT 250 WORDS)

Muscle fiber population and biochemical properties of whole body muscles in Thoroughbred horses.

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Kawai, Minako; Minami, Yoshio; Sayama, Yukiko; Kuwano, Atsutoshi; Hiraga, Atsushi; Miyata, Hirofumi

2009-10-01

We examine the muscle fiber population and metabolic properties of skeletal muscles from the whole body in Thoroughbred horses. Postmortem samples were taken from 46 sites in six Thoroughbred horses aged between 3 and 6 years. Fiber type population was determined on muscle fibers stained with monoclonal antibody to each myosin heavy chain isoform and metabolic enzyme activities were determined spectrophotometrically. Histochemical analysis demonstrated that most of the muscles had a high percentage of Type IIa fibers. In terms of the muscle characteristic in several parts of the horse body, the forelimb muscles had a higher percentage of Type IIa fiber and a significantly lower percentage of Type IIx fiber than the hindlimb muscles. The muscle fiber type populations in the thoracic and trunk portion were similar to those in the hindlimb portion. Biochemical analysis indicated high succinate dehydrogenase activity in respiratory-related muscle and high phosphofructokinase activity in hindlimbs. We suggested that the higher percentage of Type IIa fibers in Thoroughbred racehorses is attributed to training effects. To consider further the physiological significance of each part of the body, data for the recruitment pattern of each muscle fiber type during exercise are needed. The muscle fiber properties in this study combined with the recruitment data would provide fundamental information for physiological and pathological studies in Thoroughbred horses.

EFFECT OF UPPER-LIMB AND THORACIC MUSCLE STRENGTH ON 6-MIN WALK DISTANCE IN COPD PATIENTS

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D Varalakshmi

2014-06-01

Full Text Available Background: Chronic obstructive pulmonary disease (COPD is the only cause of death from chronic disease that will increase worldwide until 2020 and it represents a big burden for patients and society. Patients with COPD characteristically show poor exercise performance indicated by a marked reduction in both peak pulmonary 02 uptake and work rate at peak exercise. The sequelae of exercise intolerance include increased difficulty in performing daily tasks, etc. The objective of the study is to investigate the influence of thoracic and upper limb muscle function on 6-min walk distance (6MWD in patients with COPD. Method: Thirty eight COPD patients were included if they fulfilled the criteria for COPD according to the Global Initiative for Chronic Obstructive Lung Disease guidelines. Prospective, cross-sectional design with sample size of 38 patients. All patients performed 6MWD and 1RM exercises. Results: To study the correlation between variables, Pearson or Spearman coefficients of correlation were used with the level of statistical significance set at 5%.Results of this study suggested for the first time that thoracic muscle strength is a predictor of 6MWD in COPD patients. It also confirms the influence of respiratory muscle strength (Pimax, dyspnea, on the 6MWD of these patients. Conclusion: It is concluded that peripheral muscle strength, respiratory muscle strength, and the sensation of dyspnea all have an influence on the capacity of COPD patients to perform exercises.

The effects of work surface hardness on mechanical stress, muscle activity, and wrist postures.

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Kim, Jeong Ho; Aulck, Lovenoor; Trippany, David; Johnson, Peter W

2015-01-01

Contact pressure is a risk factor which can contribute to musculoskeletal disorders. The objective of the present study was to determine whether a work surface with a soft, pliable front edge could reduce contact pressure, muscle activity, and subjective musculoskeletal comfort, and improve wrist posture relative to a conventional, hard work surface. In a repeated-measures blinded experiment with eighteen subjects (8 females and 10 males), contact pressure, wrist posture, typing productivity, perceived fatigue, wrist and shoulder muscle activity, and subjective comfort were compared between the two different work surfaces during keyboard use, mouse use and mixed mouse and keyboard use. The results showed that across the three modes of computer work, the contact pressure was lower on the soft-edge work surface compared to the conventional work surface (p's work surfaces. Given the significant reduction in contact pressure and corresponding lower ratings in perceived fatigue, the soft-edge work surface subjectively and objectively improved measures of contact stress which may reduce physical exposures associated with the onset and development of musculoskeletal disorders.

Skeletal muscle and hormonal adaptation to physical training in the rat

DEFF Research Database (Denmark)

Henriksson, J; Svedenhag, J; Richter, Erik

1985-01-01

The main purpose of the present study was to test the hypothesis that adrenergic stimulation of muscle fibres during exercise is a major stimulus for the training-induced enhancement of skeletal muscle respiratory capacity. Therefore, Sprague-Dawley rats either underwent bilateral surgical ablati...

Unusual Respiratory Manifestations in Two Young Adults with Duchenne Muscular Dystrophy

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Julie Lemay

2012-01-01

Full Text Available Adult respirologists are often involved in the evaluation and treatment of young adult patients with Duchenne muscular dystrophy. In this context, the most frequent respiratory complication is nocturnal and daytime hypoventilation related to respiratory muscle weakness. The present article describes cases of Duchenne muscular dystrophy involving two brothers, 17 and 19 years of age, respectively, who presented with less frequently reported respiratory complications of their disease: obstructive sleep apnea and Cheyne-Stokes respiration with central apnea, which were believed to be partially or completely related to congestive cardiomyopathy.

Non-invasive assessment of exercise performance in children with cystic fibrosis (CF) and non-cystic fibrosis bronchiectasis: is there a CF specific muscle defect?

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Rosenthal, Mark; Narang, Indra; Edwards, Liz; Bush, Andrew

2009-03-01

Peripheral muscle dysfunction is increasingly recognized as complicating respiratory disease, but this is difficult to measure non-invasively. Can skeletal muscle function and efficiency be measured during exercise non-invasively using respiratory mass spectrometry (RMS); and is the known exercise dysfunction in cystic fibrosis (CF) children related in part to a disease specific defect of skeletal muscle, or a non-specific manifestation of chronic airway infection and inflammation. Calculations of effective pulmonary blood flow and stroke volume, blood oxygen content and oxygen dispatch from the lungs, skeletal muscle oxygen extraction and consumption, anerobic threshold and capacity, and gross, net and work efficiency in 106 controls and 36 children (18 CF) with bronchiectasis, all aged from 8 to 17 years. Normal values for control subjects are tabulated. CF and non-CF bronchiectatic subjects had similar physiology, and skeletal muscle abnormalities could not be detected. Reduced oxygen dispatch from the lungs, due to an inability to raise stroke volume, without an increase in functional residual capacity was the major factor in reduced exercise ability. Non-invasive RMS can be used to determine skeletal muscle function in children. The changes observed in CF subjects were very similar to non-CF bronchiectatic subjects and thus a CF specific defect was not demonstrated.

The role of eccentric regime of leg muscle work in alpine skiing

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Ropret Robert

2017-01-01

Full Text Available Alpine skiing is characterized by a great number of leg movements with muscle contractions in eccentric regime. The role of these movements is to absorb gravitation and inertial forces, manage skis more precisely and maintain balance. Recent studies have determined the volume, duration and intenisty of eccentric contractions as well as the basic characteristics of movement amplitudes and velocities. Based on the previous findings the experiments involving eccentric training using a bicycle ergometer confirmed a positive impact that this kind of training has on increasing maximum power, strength, endurance, coordination, injury prevention, metabolic work efficiency, more efficient work with longer muscle length and its role in miming skiers' movements. This paper is an review of the studies so far in the field of kinematics, skiing dynamics and the effect of eccentric training on the development of athletes' performances.

Reliability and validity of the test of incremental respiratory endurance measures of inspiratory muscle performance in COPD.

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Formiga, Magno F; Roach, Kathryn E; Vital, Isabel; Urdaneta, Gisel; Balestrini, Kira; Calderon-Candelario, Rafael A; Campos, Michael A; Cahalin, Lawrence P

2018-01-01

The Test of Incremental Respiratory Endurance (TIRE) provides a comprehensive assessment of inspiratory muscle performance by measuring maximal inspiratory pressure (MIP) over time. The integration of MIP over inspiratory duration (ID) provides the sustained maximal inspiratory pressure (SMIP). Evidence on the reliability and validity of these measurements in COPD is not currently available. Therefore, we assessed the reliability, responsiveness and construct validity of the TIRE measures of inspiratory muscle performance in subjects with COPD. Test-retest reliability, known-groups and convergent validity assessments were implemented simultaneously in 81 male subjects with mild to very severe COPD. TIRE measures were obtained using the portable PrO2 device, following standard guidelines. All TIRE measures were found to be highly reliable, with SMIP demonstrating the strongest test-retest reliability with a nearly perfect intraclass correlation coefficient (ICC) of 0.99, while MIP and ID clustered closely together behind SMIP with ICC values of about 0.97. Our findings also demonstrated known-groups validity of all TIRE measures, with SMIP and ID yielding larger effect sizes when compared to MIP in distinguishing between subjects of different COPD status. Finally, our analyses confirmed convergent validity for both SMIP and ID, but not MIP. The TIRE measures of MIP, SMIP and ID have excellent test-retest reliability and demonstrated known-groups validity in subjects with COPD. SMIP and ID also demonstrated evidence of moderate convergent validity and appear to be more stable measures in this patient population than the traditional MIP.

Transient hypoxic respiratory failure in a patient with severe hypophosphatemia.

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Oud, Lavi

2009-03-01

Respiratory failure in severely hypophosphatemic patients has been attributed to respiratory muscle weakness, leading to ventilatory failure. While frequently documenting hypercarbic respiratory failure, previous reports of hypophosphatemia-related respiratory failure in patients otherwise free of pulmonary or airway disease often did not provide sufficient information on gas exchange and pulmonary function, precluding inference on alternative or additional sources of respiratory dysfunction in this population. We report a case of acute hypoxic respiratory failure in a 26 year-old bulimic woman with severe hypophosphatemia. The patient presented with acute onset of dyspnea, paresthesias, limb shaking, and severe hyperventilation. SpO2 was 74%, requiring administration of 100% O2, with normal chest radiograph. Serum phosphate was <0.3 mmol/liter (1.0 mg/dL). Further evaluation did not support pulmonary, vascular, neurogenic or external exposure-related causes of hypoxic respiratory failure, which rapidly resolved with parenteral correction of hypophosphatemia. To date, hypoxic respiratory failure has not been reported in association with hypophosphatemia. Increased awareness and further investigations can help elucidate the mechanisms of hypophosphatemia-associated hypoxemia.

Validity, prognostic value and optimal cutoff of respiratory muscle strength in patients with chronic heart failure changes with beta-blocker treatment.

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Frankenstein, Lutz; Nelles, Manfred; Meyer, F Joachim; Sigg, Caroline; Schellberg, Dieter; Remppis, B Andrew; Katus, Hugo A; Zugck, Christian

2009-08-01

Training studies frequently use maximum inspiratory mouth occlusion pressure (PImax) as a therapeutic target and surrogate marker. For patients on beta-blocker (BBL), prognostic data allowing this extrapolation do not exist. Furthermore, the effects of BBL, mainstay of modern chronic heart failure therapy, on respiratory muscle function remain controversial. Finally, no proper separate cutoff according to treatment exists. Prospective, observational inclusion of patients with stable systolic chronic heart failure and recording of 1 year and all-time mortality for endpoint analysis. In 686 patients, 81% men, 494 patients on BBL, PImax was measured along with clinical evaluation. The median follow-up was 50 months (interquartile range: 26-75 months). Patients with or without BBL did not differ significantly for PImax, percentage of predicted PImax or other marker of disease severity. PImax was a significant (hazard ratio: 0.925; 95% confidence interval: 0.879-0.975; chi(2): 8.62) marker of adverse outcome, independent of BBL-status or aetiology. Percentage of predicted PImax was not independent of PImax. The cutoff identified through receiver-operated characteristics for 1-year mortality was 4.14 kPa for patients on BBL and 7.29 kPa for patients not on BBL. When separated accordingly, 1-year mortality was 8.5 versus 21.4%, P=0.02, for patients not on BBL and 4.3 versus 16.2%, P<0.001, for patients on BBL. This study fills the gap between trials targeting respiratory muscle on a functional basis and the resultant prognostic information with regard to BBL. BBL lowered the optimal PImax cutoff values for risk stratification without changing the measured values of PImax. This should be considered at inclusion and evaluation of trials and interpretation of exercise parameters.

Effects of an aquatic versus non-aquatic respiratory exercise program on the respiratory muscle strength in healthy aged persons Efeitos de um programa de cinesioterapia respiratória desenvolvido em dois meios diferentes - aquático e solo - na força muscular respiratória de idosos saudáveis

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Maiza Ritomy Ide

2005-04-01

Full Text Available Aging of the worldwide population is a concern of most governmental entities, spanning practically all areas of prevention and rehabilitation. Aging leads to physiological alterations that result in adverse social and financial effects. There is a trend to emphasize prevention, which is less expensive and socially more desirable than therapeutic intervention. PURPOSE: To assess the effect of a program of aquatic versus non-aquatic respiratory exercises on respiratory muscle strength in healthy aged persons. METHODS: The respiratory muscle strength was measured in 81 subjects between 60 and 65 years, 59 of which completed the program. Subjects were randomized into 3 groups. Gaquatic undertook a program of respiratory exercise in an aquatic environment. Gnon-aquatic undertook the same program in a non-aquatic environment. Gcontrol acted as the negative control. Programs were applied three times a week for 10 consecutive weeks. Subsequently, subjects were reevaluated, and results compared to each individual's pre-treatment own result and between the groups. The data were statistically analyzed using the paired t test and the Sign test. Comparisons between the groups were performed through parametric and nonparametric variance. A comparison of Gaquatic and Gnon-aquatic versus Gcontrol was performed using the Dunnett test. RESULTS: A significant improvement in the inspiratory muscle strength in the Gaquatic group compared to the Gcontrol, group was found, suggesting beneficial effects mediated by the aquatic exercise. The expiratory muscles did not show significant alterations. CONCLUSION: Aquatic respiratory exercise improves the inspiratory muscle strength of healthy aged persons. However, neither aquatic nor non-aquatic respiratory exercise influences the expiratory muscle strength.O envelhecimento da população mundial é uma preocupação para grande parte das entidades governamentais. Acarreta alterações fisiológicas em todo o organismo e

Complex myograph allows the examination of complex muscle contractions for the assessment of muscle force, shortening, velocity, and work in vivo

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Ruhschulte Hainer

2008-07-01

Full Text Available Abstract Background The devices used for in vivo examination of muscle contractions assess only pure force contractions and the so-called isokinetic contractions. In isokinetic experiments, the extremity and its muscle are artificially moved with constant velocity by the measuring device, while a tetanic contraction is induced in the muscle, either by electrical stimulation or by maximal voluntary activation. With these systems, experiments cannot be performed at pre-defined, constant muscle length, single contractions cannot be evaluated individually and the separate examination of the isometric and the isotonic components of single contractions is not possible. Methods The myograph presented in our study has two newly developed technical units, i.e. a. a counterforce unit which can load the muscle with an adjustable, but constant force and b. a length-adjusting unit which allows for both the stretching and the contraction length to be infinitely adjustable independently of one another. The two units support the examination of complex types of contraction and store the counterforce and length-adjusting settings, so that these conditions may be accurately reapplied in later sessions. Results The measurement examples presented show that the muscle can be brought to every possible pre-stretching length and that single isotonic or complex isometric-isotonic contractions may be performed at every length. The applied forces act during different phases of contraction, resulting into different pre- and after-loads that can be kept constant – uninfluenced by the contraction. Maximal values for force, shortening, velocity and work may be obtained for individual muscles. This offers the possibility to obtain information on the muscle status and to monitor its changes under non-invasive measurement conditions. Conclusion With the Complex Myograph, the whole spectrum of a muscle's mechanical characteristics may be assessed.

Cardiac, skeletal, and smooth muscle mitochondrial respiration: are all mitochondria created equal?

Science.gov (United States)

Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I; Trinity, Joel D; Hyngstrom, John R; Garten, Ryan S; Diakos, Nikolaos A; Ives, Stephen J; Dela, Flemming; Larsen, Steen; Drakos, Stavros; Richardson, Russell S

2014-08-01

Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial respiration. Therefore, the present study examined mitochondrial respiratory rates in smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscles. Cardiac, skeletal, and smooth muscles were harvested from a total of 22 subjects (53 ± 6 yr), and mitochondrial respiration was assessed in permeabilized fibers. Complex I + II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac to skeletal to smooth muscles (54 ± 1, 39 ± 4, and 15 ± 1 pmol·s(-1)·mg(-1), P respiration rates were normalized by CS (respiration per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, complex I state 2 normalized for CS activity, an index of nonphosphorylating respiration per mitochondrial content, increased progressively from cardiac to skeletal to smooth muscles, such that the respiratory control ratio, state 3/state 2 respiration, fell progressively from cardiac to skeletal to smooth muscles (5.3 ± 0.7, 3.2 ± 0.4, and 1.6 ± 0.3 pmol·s(-1)·mg(-1), P respiration highlight the existence of intrinsic functional differences between these muscle mitochondria. This likely influences the efficiency of oxidative phosphorylation and could potentially alter ROS production.

Respiratory exercise in amyotrophic lateral sclerosis.

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Pinto, Susana; Swash, Michael; de Carvalho, Mamede

2012-01-01

We have evaluated the potential role of respiratory exercise by implementing specific inspiratory muscle training in a selected population of early-affected amyotrophic lateral sclerosis (ALS) patients. We studied 26 patients with ALS with normal respiratory function using two groups of patients in a parallel, control-group, randomized, delayed-start design. Patients in the first group (G1) started the active inspiratory exercise programme at entry and were followed for eight months, while the second group (G2) of patients followed a placebo exercise programme for the first four months and then active exercise for the second four-month period. The primary outcome measure was the ALSFRS. Respiratory tests, neurophysiological measurements, fatigue and quality of life scales were secondary outcomes. Analysis of covariance was used to compare changes between and within groups. Results showed that there was no significant difference between the two patient groups. Within-group analysis suggested that inspiratory exercise promotes a transient improvement in the respiratory subscore and in the maximal voluntary ventilation, peak expiratory flow, and sniff inspiratory pressure. In conclusion, there was no clear positive or negative outcome of the respiratory exercise protocol we have proposed, but we cannot rule out a minor positive effect. Exercise regimes merit more detailed clinical evaluation in ALS.

Functional Magnetic Stimulation of Inspiratory and Expiratory Muscles in Subjects With Tetraplegia.

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Zhang, Xiaoming; Plow, Ela; Ranganthan, Vinoth; Huang, Honglian; Schmitt, Melissa; Nemunaitis, Gregory; Kelly, Clay; Frost, Frederick; Lin, Vernon

2016-07-01

Respiratory complications are major causes of morbidity and mortality in persons with a spinal cord injury, partly because of respiratory muscle paralysis. Earlier investigation has demonstrated that functional magnetic stimulation (FMS) can be used as a noninvasive technology for activating expiratory muscles, thus producing useful expiratory functions (simulated cough) in subjects with spinal cord injury. To evaluate the effectiveness of FMS for conditioning inspiratory and expiratory muscles in persons with tetraplegia. A prospective before and after trial. FMS Laboratory, Louis Stokes Cleveland VA Medical Center, Cleveland, OH. Six persons with tetraplegia. Each subject participated in a 6-week FMS protocol for conditioning the inspiratory and expiratory muscles. A magnetic stimulator was used with the center of a magnetic coil placed at the C7-T1 and T9-T10 spinous processes, respectively. Pulmonary function tests were performed before, during, and after the protocol. Respiratory variables included maximal inspiratory pressure (MIP), inspiratory reserve volume (IRV), peak inspiratory flow (PIF), maximal expiratory pressure (MEP), expiratory reserve volume (ERV), and peak expiratory flow (PEF). After 6 weeks of conditioning, the main outcome measurements (mean ± standard error) were as follows: MIP, 89.6 ± 7.3 cm H2O; IRV, 1.90 ± 0.34 L; PIF, 302.4 ± 36.3 L/min; MEP, 67.4 ± 11.1 cm H2O; ERV, 0.40 ± 0.06 L; and PEF, 372.4 ± 31.9 L/min. These values corresponded to 117%, 107%, 136%, 109%, 130%, and 124% of pre-FMS conditioning values, respectively. Significant improvements were observed in MIP (P = .022), PIF (P = .0001), and PEF (P = .0006), respectively. When FMS was discontinued for 4 weeks, these values showed decreases from their values at the end of the conditioning protocol, which suggests that continual FMS may be necessary to maintain improved respiratory functions. FMS conditioning of the inspiratory and expiratory muscles improved

Effect of pilates method on inspiratory and expiratory muscle strength in the elderly

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Beatriz Mendes Tozim

2018-03-01

Full Text Available With aging, the respiratory muscle strength decreases and the pilates method is a technique that uses respiration as one of its principles. The present study has the aim of analyzing the influence of the pilates method on respiratory muscle strength in older women. For the evaluation of respiratory muscle strength (inspiratory and expiratory, manovacuometer was used. Thirty-one older women were divided into two groups: 14 participated in the pilates group and 17 in the control group. Participants of the pilates group performed 16 sessions of pilates method with an hour of training, twice week for eight weeks. The control group participated in four educational lectures for eight weeks. For statistical analysis, Shapiro-Wilk, ANOVA for repeated measures (p <0.05 and Cohen’s D index were performed. The results showed significant difference and the mean effect for the Cohen’s D index expiratory muscle strength of the pilates group when comparing before (69.71 ± 25.48 and after (85.23 ± 22.21 training (p<0.05 with an increase of 23%. The results of inspiratory muscle strength were not significant but presented an average effect for the Cohen’s D index for the pilates group before (69.71 ± 35.46 and after (88.00 ± 34.87 training, with an increase of 27%. The control group did not present significant differences for the variables evaluated. It could be concluded that the pilates method is effective in improving expiratory muscle strength and provides positive effects on the increase in inspiratory muscle strength.

Respiratory chain deficiency in aged spinal motor neurons☆

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Rygiel, Karolina A.; Grady, John P.; Turnbull, Doug M.

2014-01-01

Sarcopenia, muscle wasting, and strength decline with age, is an important cause of loss of mobility in the elderly individuals. The underlying mechanisms are uncertain but likely to involve defects of motor nerve, neuromuscular junction, and muscle. Loss of motor neurons with age and subsequent denervation of skeletal muscle has been recognized as one of the contributing factors. This study investigated aspects of mitochondrial biology in spinal motor neurons from elderly subjects. We found that protein components of complex I of mitochondrial respiratory chain were reduced or absent in a proportion of aged motor neurons–a phenomenon not observed in fetal tissue. Further investigation showed that complex I-deficient cells had reduced mitochondrial DNA content and smaller soma size. We propose that mitochondrial dysfunction in these motor neurons could lead to the cell loss and ultimately denervation of muscle fibers. PMID:24684792

Effects of electromyographic and mechanomyographic biofeedback on upper trapezius muscle activity during standardized computer work

DEFF Research Database (Denmark)

Madeleine, Pascal; Vedsted, Pernille; Blangsted, Anne Katrine

2006-01-01

The purpose of this laboratory study was to investigate the effects of surface electromyography (EMG)- and mechanomyography (MMG)-based audio and visual biofeedback during computer work. Standardized computer work was performed for 3 min with/without time constraint and biofeedback in a randomize...... alternative to EMG in ergonomics. A lowering of the trapezius muscle activity may contribute to diminish the risk of work related musculoskeletal disorders development.......The purpose of this laboratory study was to investigate the effects of surface electromyography (EMG)- and mechanomyography (MMG)-based audio and visual biofeedback during computer work. Standardized computer work was performed for 3 min with/without time constraint and biofeedback in a randomized......) values as well as the work performance in terms of number of completed graph/mouse clicks/errors, the rating of perceived exertion (RPE) and the usefulness of the biofeedback were assessed. The duration of muscle activity above the threshold was significantly lower with MMG compared with EMG as source...

Feasibility For Measuring Transverse Area Ratios And Asymmetry Of Lumbosacral Region Paraspinal Muscles In Working Dogs Using Computed Tomography

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Bethany eCain

2016-05-01

Full Text Available Objectives: Describe computed tomographic (CT anatomy of canine lumbosacral paraspinal muscles, a method for measuring paraspinal muscle transverse area ratios and asymmetry using CT, and application of this method in a small sample of working dogs with versus without lumbosacral pain.Methods: Published anatomy references and atlases were reviewed and discrepancies resolved by examination of anatomic specimens and multi-planar reformatted images to describe transverse CT anatomy of lumbosacral region paraspinal muscles. Sixteen Belgian malinois military working dogs were retrospectively recruited and assigned to lumbosacral pain positive versus negative groups based on medical record entries. A single observer unaware of dog group measured CT transverse areas of paraspinal muscles and adjacent vertebral bodies, in triplicate, for L5-S1 vertebral locations. A statistician compared muscle transverse area ratios and asymmetry at each vertebral location between groups. Results: The relative co-efficient of variation for triplicate CT area measurements averaged 2.15% (N=16. Multifidus lumborum (L6-7, psoas/iliopsoas (L5-6, L6-7, and sacrocaudalis dorsalis lateralis (L6-7, L7-S1 transverse area ratios were significantly smaller in dogs with lumbosacral pain (n=11 vs. without lumbosacral pain (n=5 (p< 0.05. Muscle asymmetry values were not significantly greater in dogs with vs. without lumbosacral pain. Clinical relevance: Computed tomographic morphometry of lumbosacral region paraspinal muscles is a feasible objective method for use in future evidence-based research studies in working dogs. Potential future research applications include determining whether decreased paraspinal muscle area ratios and/or increased paraspinal muscle asymmetry could be used as markers for preclinical lumbosacral pain in stoic dogs or risk factors for other injuries in high performance canine athletes; or determining whether core muscle strengthening exercise prescriptions

Hereditary myopathies with early respiratory insufficiency in adults.

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Naddaf, Elie; Milone, Margherita

2017-11-01

Hereditary myopathies with early respiratory insufficiency as a predominant feature of the clinical phenotype are uncommon and underestimated in adults. We reviewed the clinical and laboratory data of patients with hereditary myopathies who demonstrated early respiratory insufficiency before the need for ambulatory assistance. Only patients with disease-causing mutations or a specific histopathological diagnosis were included. Patients with cardiomyopathy were excluded. We identified 22 patients; half had isolated respiratory symptoms at onset. The diagnosis of the myopathy was often delayed, resulting in delayed ventilatory support. The most common myopathies were adult-onset Pompe disease, myofibrillar myopathy, multi-minicore disease, and myotonic dystrophy type 1. Single cases of laminopathy, MELAS (mitochondrial encephalomyopathy with lactic acidosis and strokelike events), centronuclear myopathy, and cytoplasmic body myopathy were identified. We highlighted the most common hereditary myopathies associated with early respiratory insufficiency as the predominant clinical feature, and underscored the importance of a timely diagnosis for patient care. Muscle Nerve 56: 881-886, 2017. © 2017 Wiley Periodicals, Inc.

Adipose triglyceride lipase plays a key role in the supply of the working muscle with fatty acids

DEFF Research Database (Denmark)

Schoiswohl, Gabriele; Schweiger, Martina; Schreiber, Renate

2010-01-01

Fatty acids (FA) are mobilized from triglyceride (TG) stores during exercise to supply the working muscle with energy. Mice deficient for adipose triglyceride lipase (ATGLko)exhibit defective lipolysis and accumulate TG in adipose tissue and muscle suggesting that ATGL deficiency affects energy a...

A closed-loop model of the respiratory system: focus on hypercapnia and active expiration.

Directory of Open Access Journals (Sweden)

Yaroslav I Molkov

Full Text Available Breathing is a vital process providing the exchange of gases between the lungs and atmosphere. During quiet breathing, pumping air from the lungs is mostly performed by contraction of the diaphragm during inspiration, and muscle contraction during expiration does not play a significant role in ventilation. In contrast, during intense exercise or severe hypercapnia forced or active expiration occurs in which the abdominal "expiratory" muscles become actively involved in breathing. The mechanisms of this transition remain unknown. To study these mechanisms, we developed a computational model of the closed-loop respiratory system that describes the brainstem respiratory network controlling the pulmonary subsystem representing lung biomechanics and gas (O2 and CO2 exchange and transport. The lung subsystem provides two types of feedback to the neural subsystem: a mechanical one from pulmonary stretch receptors and a chemical one from central chemoreceptors. The neural component of the model simulates the respiratory network that includes several interacting respiratory neuron types within the Bötzinger and pre-Bötzinger complexes, as well as the retrotrapezoid nucleus/parafacial respiratory group (RTN/pFRG representing the central chemoreception module targeted by chemical feedback. The RTN/pFRG compartment contains an independent neural generator that is activated at an increased CO2 level and controls the abdominal motor output. The lung volume is controlled by two pumps, a major one driven by the diaphragm and an additional one activated by abdominal muscles and involved in active expiration. The model represents the first attempt to model the transition from quiet breathing to breathing with active expiration. The model suggests that the closed-loop respiratory control system switches to active expiration via a quantal acceleration of expiratory activity, when increases in breathing rate and phrenic amplitude no longer provide sufficient

Dysrhythmias of the respiratory oscillator

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Paydarfar, David; Buerkel, Daniel M.

1995-03-01

Breathing is regulated by a central neural oscillator that produces rhythmic output to the respiratory muscles. Pathological disturbances in rhythm (dysrhythmias) are observed in the breathing pattern of children and adults with neurological and cardiopulmonary diseases. The mechanisms responsible for genesis of respiratory dysrhythmias are poorly understood. The present studies take a novel approach to this problem. The basic postulate is that the rhythm of the respiratory oscillator can be altered by a variety of stimuli. When the oscillator recovers its rhythm after such perturbations, its phase may be reset relative to the original rhythm. The amount of phase resetting is dependent upon stimulus parameters and the level of respiratory drive. The long-range hypothesis is that respiratory dysrhythmias can be induced by stimuli that impinge upon or arise within the respiratory oscillator with certain combinations of strength and timing relative to the respiratory cycle. Animal studies were performed in anesthetized or decerebrate preparations. Neural respiratory rhythmicity is represented by phrenic nerve activity, allowing use of open-loop experimental conditions which avoid negative chemical feedback associated with changes in ventilation. In animal experiments, respiratory dysrhythmias can be induced by stimuli having specific combinations of strength and timing. Newborn animals readily exhibit spontaneous dysrhythmias which become more prominent at lower respiratory drives. In human subjects, swallowing was studied as a physiological perturbation of respiratory rhythm, causing a pattern of phase resetting that is characterized topologically as type 0. Computational studies of the Bonhoeffer-van der Pol (BvP) equations, whose qualitative behavior is representative of many excitable systems, supports a unified interpretation of these experimental findings. Rhythmicity is observed when the BvP model exhibits recurrent periods of excitation alternating with

Human skeletal muscle mitochondrial capacity.

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Rasmussen, U F; Rasmussen, H N

2000-04-01

Under aerobic work, the oxygen consumption and major ATP production occur in the mitochondria and it is therefore a relevant question whether the in vivo rates can be accounted for by mitochondrial capacities measured in vitro. Mitochondria were isolated from human quadriceps muscle biopsies in yields of approximately 45%. The tissue content of total creatine, mitochondrial protein and different cytochromes was estimated. A number of activities were measured in functional assays of the mitochondria: pyruvate, ketoglutarate, glutamate and succinate dehydrogenases, palmitoyl-carnitine respiration, cytochrome oxidase, the respiratory chain and the ATP synthesis. The activities involved in carbohydrate oxidation could account for in vivo oxygen uptakes of 15-16 mmol O2 min-1 kg-1 or slightly above the value measured at maximal work rates in the knee-extensor model of Saltin and co-workers, i.e. without limitation from the cardiac output. This probably indicates that the maximal oxygen consumption of the muscle is limited by the mitochondrial capacities. The in vitro activities of fatty acid oxidation corresponded to only 39% of those of carbohydrate oxidation. The maximal rate of free energy production from aerobic metabolism of glycogen was calculated from the mitochondrial activities and estimates of the DeltaG or ATP hydrolysis and the efficiency of the actin-myosin reaction. The resultant value was 20 W kg-1 or approximately 70% of the maximal in vivo work rates of which 10-20% probably are sustained by the anaerobic ATP production. The lack of aerobic in vitro ATP synthesis might reflect termination of some critical interplay between cytoplasm and mitochondria.

Skeletal muscle substrate metabolism during exercise: methodological considerations

DEFF Research Database (Denmark)

Van Hall, Gerrit; González-Alonso, J; Sacchetti, M

1999-01-01

and the respiratory exchange ratio. However, if the aim is to quantify limb or muscle metabolism, invasive measurements have to be carried out, such as the determination of blood flow, arterio-venous (a-v) difference measurements for O2 and relevant substrates, and biopsies of the active muscle. As many substrates...... substrates. There are several methodological concerns to be aware of when studying the metabolic response to exercise in human subjects. These concerns include: (1) the muscle mass involved in the exercise is largely unknown (bicycle or treadmill). Moreover, whether the muscle sample obtained from a limb......; (3) the use of net limb glycerol release to estimate lipolysis is probably not valid (triacylglycerol utilization by muscle), since glycerol can be metabolized in skeletal muscle; (4) the precision of blood-borne substrate concentrations during exercise measured by a-v difference is hampered since...

Respiratory mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Mostert, J.W. (Pretoria Univ. (South Africa). Dept. of Anesthesiology)

1983-06-01

The high degree of technical perfection of the respiratory mass spectrometer has rendered the instrument feasible for routine monitoring of anesthetized patients. It is proposed that the difference between inspired and expired oxygen tension in mm Hg be equated with whole body oxygen consumption in ml/min/M/sup 2/ body-surface area at STPD, by the expedient of multiplying tension-differences by a factor of 2. Years of experience have confirmed the value of promptly recognizing sudden drops in this l/E tension difference below 50 mm Hg indicative of metabolic injury from hypovolemia or respiratory depression. Rises in l/E tension-differences were associated with shivering as well as voluntary muscle activity. Tension differences of less than 25 mm Hg (equated with a whole-body O/sub 2/ consumption of less than 50 ml O/sub 2//min/M/sup 2/) occurred in a patient in the sitting position for posterior fossa exploration without acidosis, hypoxia or hypotension for several hours prior to irreversible cardiac arrest. The value of clinical monitoring by mass spectrometry is especially impressive in open-heart surgery.

Respiratory care management information systems.

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Ford, Richard M

2004-04-01

Hospital-wide computerized information systems evolved from the need to capture patient information and perform billing and other financial functions. These systems, however, have fallen short of meeting the needs of respiratory care departments regarding work load assessment, productivity management, and the level of outcome reporting required to support programs such as patient-driven protocols. The respiratory care management information systems (RCMIS) of today offer many advantages over paper-based systems and hospital-wide computer systems. RCMIS are designed to facilitate functions specific to respiratory care, including assessing work demand, assigning and tracking resources, charting, billing, and reporting results. RCMIS incorporate mobile, point-of-care charting and are highly configurable to meet the specific needs of individual respiratory care departments. Important and substantial benefits can be realized with an RCMIS and mobile, wireless charting devices. The initial and ongoing costs of an RCMIS are justified by increased charge capture and reduced costs, by way of improved productivity and efficiency. It is not unusual to recover the total cost of an RCMIS within the first year of its operation. In addition, such systems can facilitate and monitor patient-care protocols and help to efficiently manage the vast amounts of information encountered during the practitioner's workday. Respiratory care departments that invest in RCMIS have an advantage in the provision of quality care and in reducing expenses. A centralized respiratory therapy department with an RCMIS is the most efficient and cost-effective way to monitor work demand and manage the hospital-wide allocation of respiratory care services.

Prognostic factors for respiratory sickness absence and return to work among blue collar workers and office personnel

NARCIS (Netherlands)

E.C. Alexopoulos (Evangelos); A. Burdorf (Alex)

2001-01-01

textabstractOBJECTIVES: To analyze factors that determine the occurrence of sickness absence due to respiratory disorders and the time it takes to return to work. METHODS: A longitudinal study with 2 year follow up was conducted among 326 male blue collar and white

Poison hemlock-induced respiratory failure in a toddler.

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West, Patrick L; Horowitz, B Zane; Montanaro, Marc T; Lindsay, James N

2009-11-01

The ingestion of poison hemlock, or Conium maculatum, is described in a 2-year-old boy. He had the onset of abdominal pain and weakness after being fed C. maculatum picked by his sister from the roadside 2 hours earlier. He had a rapidly progressive muscular weakness and was intubated for respiratory failure. His symptoms completely resolved within 24 hours of the ingestion. Conium maculatum is a common weed that causes toxicity by its primary toxin, coniine, which stimulates nicotinic receptors and causes a syndrome of rapidly progressive muscle weakness and paralysis. We describe the course of a benign-appearing plant ingestion resulting in respiratory failure.

Cardio-respiratory and plasma lactate responses to exercise with low draught resistances in standardbred trotters.

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Gottlieb-Vedi, M; Essén-Gustavsson, B; Lindholm, A

1996-12-01

Five Standardbred trotters performed treadmill exercise with incrementally increasing trotting velocities for 2 min intervals in three different tests until fatigue. Each test was performed with draught loads of either 10, 20 or 30 kilopond (kp). Each trotting interval was followed by 2 min periods at a walk without draught load. Recordings were made of heart rate (HR), respiratory rate (RR), plasma lactate (PLA) and stride frequency (SF) at the end of each trotting interval. The HR increased to average values of 191 +/- 10,203 +/- 10 and 214 +/- 7 bpm and PLA increased to 3.8 +/- 0.7, 7.3 +/- 3.8 and 10.8 +/- 6.4 mmol/l at 9 m/s in the three tests, respectively. The HR response to exercise was significantly higher with increasing draught loads, and PLA was significantly higher with 30 kp compared to 10 kp draught resistance. The lowest respiratory rate was seen in the test with 30 kp loading. Peak oxygen uptake (VO2peak) was measured in a separate test on a sloped treadmill with increasing velocities without draught load and averaged 70.4 +/- 9.11/min. Muscle biopsies were taken from the gluteus muscle. Individual variations were seen in VO2peak, muscle fibre composition and HR and PLA responses to exercise. In conclusion, at a certain velocity a small increase in draught resistance from 10 to 30 kp significantly increases both the HR and PLA responses. At comparable work intensities the horses differed in circulatory and metabolic responses to exercise.

Use of Respiratory Mask and Influencing Factors among Workers Who Worked in Welding Department at Automotive Sector

Directory of Open Access Journals (Sweden)

Melek Nihal Esin,A. Dilek Yilmaz

2012-06-01

Full Text Available AIM: This study was designed in a cross sectional pattern in order to determine workers’ behaviors about respiratory mask use and the factors involved. METHOD: The study was conducted with 100 workers in the welding department of a factory operating in automotive sector and employing approximately 1000 people. The data in the study was collected by means of ‘Form for the Assessment of Descriptive Features of Employees’ and ‘Respiratory Mask Use Behaviors Form”, developed by the researchers; the Multidimensional Health Locus of Control Scale, developed by Wallston and De Wellis; Self-Actualization Scale and Health Responsibility Scale, developed by Walker, Sechrist and Pender. RESULTS: It was found out that a majority of the workers are aged between 26 and 33 (32%, 76% of them are married, 37% are primary school graduates and 58% of them have been working for more than 11 years. It was also determined that 60% of the workers regularly wear respiratory mask. 14% of those using masks irregularly stated that they “used a respiratory mask for a short time” and 26% of them stated that they “never wore a respiratory mask”. The findings from the study showed that factors like the physical formation of the respiratory mask, the level of information about the mask, and the cognitive perceptual factors related to the employee’s health influenced respiratory mask use. Two variables with significant odds ratios were identified thorough logistic regression analysis. Worker who reported that they had inability to breathe when wearing a mask were over 9 times (OR= 9,48, %95 CI= 1,86- 16,52 and “the time spent putting on and removing a mask” were over 4 times (OR= 4,85, %95 CI= 0,03-8,81 more likely to have never wear a respiratory mask than those who used regularly wear mask . CONCLUSION: It is considered that the results from this study could form a set of basic data for “respiratory mask use improvement programs” to be designed by

Changes in muscle strength in patients with statin myalgia.

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Panza, Gregory A; Taylor, Beth A; Roman, William; Thompson, Paul D

2014-10-15

Statins can produce myalgia or muscle pain, which may affect medication adherence. We measured the effects of statins on muscle strength in patients with previous statin myalgia. Leg isokinetic extension average power at 60° per second (-8.8 ± 10.5N-M, p = 0.02) and average peak torque at 60° per second (-14.0 ± 19.7N-M, p = 0.04) decreased slightly with statin use, but 8 of 10 other variables for leg strength did not change (all p >0.13). Handgrip, muscle pain, respiratory exchange ratio, and daily activity also did not change (all p >0.09). In conclusion, statin myalgia is not associated with reduced muscle strength or muscle performance. Published by Elsevier Inc.

Efficacy of Interventions to Improve Respiratory Function After Stroke.

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Menezes, Kênia Kp; Nascimento, Lucas R; Avelino, Patrick R; Alvarenga, Maria Tereza Mota; Teixeira-Salmela, Luci F

2018-07-01

The aim of this study was to systematically review all current interventions that have been utilized to improve respiratory function and activity after stroke. Specific searches were conducted. The experimental intervention had to be planned, structured, repetitive, purposive, and delivered with the aim of improving respiratory function. Outcomes included respiratory strength (maximum inspiratory pressure [P Imax ], maximum expiratory pressure [P Emax ]) and endurance, lung function (FVC, FEV 1 , and peak expiratory flow [PEF]), dyspnea, and activity. The quality of the randomized trials was assessed by the PEDro scale using scores from the Physiotherapy Evidence Database (www.pedro.org.au), and risk of bias was assessed in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. The 17 included trials had a mean PEDro score of 5.7 (range 4-8) and involved 616 participants. Meta-analyses showed that respiratory muscle training significantly improved all outcomes of interest: P Imax (weighted mean difference 11 cm H 2 O, 95% CI 7-15, I 2 = 0%), P Emax (8 cm H 2 O, 95% CI 2-15, I 2 = 65%), FVC (0.25 L, 95% CI 0.12-0.37, I 2 = 29%), FEV 1 (0.24 L, 95% CI 0.17-0.30, I 2 = 0%), PEF (0.51 L/s, 95% CI 0.10-0.92, I 2 = 0%), dyspnea (standardized mean difference -1.6 points, 95% CI -2.2 to -0.9; I 2 = 0%), and activity (standardized mean difference 0.78, 95% CI 0.22-1.35, I 2 = 0%). Meta-analyses found no significant results for the effects of breathing exercises on lung function. For the remaining interventions (ie, aerobic and postural exercises) and the addition of electrical stimulation, meta-analyses could not be performed. This systematic review reports 5 possible interventions used to improve respiratory function after stroke. Respiratory muscle training proved to be effective for improving inspiratory and expiratory strength, lung function, and dyspnea, and benefits were carried over to activity. However, there is still no evidence to accept or

How Lungs Work

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... Diseases > How Lungs Work How Lungs Work The Respiratory System Your lungs are part of the respiratory system, ... your sense of smell. The Parts of the Respiratory System and How They Work Airways SINUSES are hollow ...

Runners maintain locomotor-respiratory coupling following isocapnic voluntary hyperpnea to task failure.

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Stickford, Abigail S L; Stickford, Jonathon L; Tanner, David A; Stager, Joel M; Chapman, Robert F

2015-11-01

Evidence has long suggested that mammalian ventilatory and locomotor rhythms are linked, yet determinants and implications of locomotor-respiratory coupling (LRC) continue to be investigated. Anecdotally, respiratory muscle fatigue seen at the end of heavy exercise may result in an uncoupling of movement-ventilation rhythms; however, there is no scientific evidence to substantiate this claim. We sought to determine whether or not fatigue of the respiratory muscles alters locomotor-respiratory coupling patterns typically observed in highly trained individuals while running. A related query was to examine the relationship between the potential changes in LRC and measures of running economy. Twelve male distance runners ran at four submaximal workloads (68-89 % VO2peak) on two separate days while LRC was quantified. One LRC trial served as a control (CON), while the other was performed following an isocapnic voluntary hyperpnea to task failure to induce respiratory muscle fatigue (FT+). LRC was assessed as stride-to-breathing frequency ratios (SF/fB) and degree of LRC (percentage of breaths occurring during the same decile of the step cycle). Hyperpnea resulted in significant declines in maximal voluntary inspiratory (MIP) and expiratory (MEP) mouth pressures (ΔMIP = -10 ± 12 cm H2O; ΔMEP = -6 ± 9 cm H2O). There were no differences in minute ventilation between CON and FT+ (CON, all speeds pooled = 104 ± 25 L min(-1); FT+ pooled = 106 ± 23 L min(-1)). Stride frequency was not different between trials; however, breathing frequency was significantly greater during FT+ compared to CON at all speeds (CON pooled = 47 ± 10 br min(-1); FT+ pooled = 52 ± 9 br min(-1)), resulting in smaller corresponding SF/fB. Yet, the degree of LRC was the same during CON and FT+ (CON pooled = 63 ± 15 %; FT+ pooled = 64 ± 18 %). The results indicate that trained runners are able to continue entraining breath and step cycles, despite marked changes in exercise breathing frequency

[Aging of the respiratory system: anatomical changes and physiological consequences].

Science.gov (United States)

Ketata, W; Rekik, W K; Ayadi, H; Kammoun, S

2012-10-01

The respiratory system undergoes progressive involution with age, resulting in anatomical and functional changes that are exerted on all levels. The rib cage stiffens and respiratory muscles weaken. Distal bronchioles have reduced diameter and tend to be collapsed. Mobilized lung volumes decrease with age while residual volume increases. Gas exchanges are modified with a linear decrease of PaO(2) up to the age of 70 years and a decreased diffusing capacity of carbon monoxide. Ventilatory responses to hypercapnia, hypoxia and exercise decrease in the elderly. Knowledge of changes in the respiratory system related to advancing age is a medical issue of great importance in order to distinguish the effects of aging from those of diseases. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Systematic Review of Inspiratory Muscle Training After Cerebrovascular Accident.

Science.gov (United States)

Martín-Valero, Rocío; De La Casa Almeida, Maria; Casuso-Holgado, Maria Jesus; Heredia-Madrazo, Alfonso

2015-11-01

This systematic review examines levels of evidence and recommendation grades of various therapeutic interventions of inspiratory muscle training in people who have had a stroke. Benefits from different levels of force and resistance in respiratory muscles are shown in this population. This review was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) directives and was completed in November 2014. The search limits were studies published in English between 2004 and 2014. Relevant studies were searched for in MEDLINE, PEDro, OAIster, Scopus, PsycINFO, Web of Knowledge, CINAHL, SPORTDiscus, DOAJ, Cochrane, Embase, Academic Search Complete, Fuente Académica, and MedicLatina. Initially, 20 articles were identified. After analyzing all primary documents, 14 studies were excluded. Only 6 studies were relevant to this review. Three different types of interventions were found (maximum inspiratory training, controlled training, and nonintervention) in 3 different groups. One specific study compared 3 inspiratory muscle training groups with a group of breathing exercises (diaphragmatic exercises with pursed lips) and a control group. Future long-term studies with larger sample sizes are needed. It is necessary to apply respiratory muscle training as a service of the national health system and to consider its inclusion in the conventional neurological program. Copyright © 2015 by Daedalus Enterprises.

Effect of inspiratory muscle training with load compared with sham training on blood pressure in individuals with hypertension: study protocol of a double-blind randomized clinical trial.

Science.gov (United States)

Posser, Simone Regina; Callegaro, Carine Cristina; Beltrami-Moreira, Marina; Moreira, Leila Beltrami

2016-08-02

Hypertension is a complex chronic condition characterized by elevated arterial blood pressure. Management of hypertension includes non-pharmacologic strategies, which may include techniques that effectively reduce autonomic sympathetic activity. Respiratory exercises improve autonomic control over cardiovascular system and attenuate muscle metaboreflex. Because of these effects, respiratory exercises may be useful to lower blood pressure in subjects with hypertension. This randomized, double-blind clinical trial will test the efficacy of inspiratory muscle training in reducing blood pressure in adults with essential hypertension. Subjects are randomly allocated to intervention or control groups. Intervention consists of inspiratory muscle training loaded with 40 % of maximum inspiratory pressure, readjusted weekly. Control sham intervention consists of unloaded exercises. Systolic and diastolic blood pressures are co-primary endpoint measures assessed with 24 h ambulatory blood pressure monitoring. Secondary outcome measures include cardiovascular autonomic control, inspiratory muscle metaboreflex, cardiopulmonary capacity, and inspiratory muscle strength and endurance. Previously published work suggests that inspiratory muscle training reduces blood pressure in persons with hypertension, but the effectiveness of this intervention is yet to be established. We propose an adequately sized randomized clinical trial to test this hypothesis rigorously. If an effect is found, this study will allow for the investigation of putative mechanisms to mediate this effect, including autonomic cardiovascular control and metaboreflex. ClinicalTrials.gov NCT02275377 . Registered on 30 September 2014.

Myopathy in Childhood Muscle-Specific Kinase Myasthenia Gravis.

Science.gov (United States)

Kirzinger, Lukas; Khomenko, Andrei; Schulte-Mattler, Wilhelm; Backhaus, Roland; Platen, Sabine; Schalke, Berthold

2016-12-01

Adult and pediatric patients suffering from MuSK (muscle-specific kinase) -antibody positive myasthenia gravis exhibit similar features to individuals with acetylcholine receptor (AChR) antibodies, but they differ in several characteristics such as a predominant bulbar, respiratory and neck weakness, a generally worse disease severity and a tendency to develop muscle atrophy. Muscle atrophy is a rare phenomenon that is usually restricted to the facial muscles. We describe a girl with MuSK-antibody positive myasthenia gravis who developed a myopathy with severe generalized muscular weakness, muscle atrophy, and myopathic changes on electromyography. This is the first published example of a generalized myopathic syndrome in myasthenia gravis. We review the relevant literature and discuss the hypothesis of a mitochondrial myopathy as a pathogenic mechanism in MuSK-antibody positive myasthenia gravis. Copyright © 2016 Elsevier Inc. All rights reserved.

Non-invasive ventilation abolishes the IL-6 response to exercise in muscle-wasted COPD patients: a pilot study.

Science.gov (United States)

Hannink, J D C; van Hees, H W H; Dekhuijzen, P N R; van Helvoort, H A C; Heijdra, Y F

2014-02-01

Systemic inflammation in patients with chronic obstructive pulmonary disease (COPD) has been related to the development of comorbidities. The level of systemic inflammatory mediators is aggravated as a response to exercise in these patients. The aim of this study was to investigate whether unloading of the respiratory muscles attenuates the inflammatory response to exercise in COPD patients. In a cross-over design, eight muscle-wasted stable COPD patients performed 40 W constant work-rate cycle exercise with and without non-invasive ventilation support (NIV vs control). Patients exercised until symptom limitation for maximally 20 min. Blood samples were taken at rest and at isotime or immediately after exercise. Duration of control and NIV-supported exercise was similar, both 12.9 ± 2.8 min. Interleukin- 6 (IL-6) plasma levels increased significantly by 25 ± 9% in response to control exercise, but not in response to NIV-supported exercise. Leukocyte concentrations increased similarly after control and NIV-supported exercise by ∼15%. Plasma concentrations of C-reactive protein, carbonylated proteins, and production of reactive oxygen species by blood cells were not affected by both exercise modes. This study demonstrates that NIV abolishes the IL-6 response to exercise in muscle-wasted patients with COPD. These data suggest that the respiratory muscles contribute to exercise-induced IL-6 release in these patients. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Is There a Link between Mitochondrial Reserve Respiratory Capacity and Aging?

DEFF Research Database (Denmark)

Hansen, Thomas Lau; Rasmussen, Lene Juel; Madsen, Claus Desler

2012-01-01

Oxidative phosphorylation is an indispensable resource of ATP in tissues with high requirement of energy. If the ATP demand is not met, studies suggest that this will lead to senescence and cell death in the affected tissue. The term reserve respiratory capacity or spare respiratory capacity...... is used to describe the amount of extra ATP that can be produced by oxidative phosphorylation in case of a sudden increase in energy demand. Depletion of the reserve respiratory capacity has been related to a range of pathologies affecting high energy requiring tissues. During aging of an organism......, and as a result of mitochondrial dysfunctions, the efficiency of oxidative phosphorylation declines. Based on examples from the energy requiring tissues such as brain, heart, and skeletal muscle, we propose that the age-related decline of oxidative phosphorylation decreases the reserve respiratory capacity...

Mechanism and Clinical Importance of Respiratory Failure Induced by Anticholinesterases

Directory of Open Access Journals (Sweden)

Ivosevic Anita

2017-12-01

Full Text Available Respiratory failure is the predominant cause of death in humans and animals poisoned with anticholinesterases. Organophosphorus and carbamate anticholinesterases inhibit acetylcholinesterase irreversibly and reversibly, respectively. Some of them contain a quaternary atom that makes them lipophobic, limiting their action at the periphery, i.e. outside the central nervous system. They impair respiratory function primarily by inducing a desensitization block of nicotinic receptors in the neuromuscular synapse. Lipophilic anticholinesterases inhibit the acetylcholinesterase both in the brain and in other tissues, including respiratory muscles. Their doses needed for cessation of central respiratory drive are significantly less than doses needed for paralysis of the neuromuscular transmission. Antagonist of muscarinic receptors atropine blocks both the central and peripheral muscarinic receptors and effectively antagonizes the central respiratory depression produced by anticholinesterases. To manage the peripheral nicotinic receptor hyperstimulation phenomena, oximes as acetylcholinesterase reactivators are used. Addition of diazepam is useful for treatment of seizures, since they are cholinergic only in their initial phase and can contribute to the occurrence of central respiratory depression. Possible involvement of central nicotinic receptors as well as the other neurotransmitter systems – glutamatergic, opioidergic – necessitates further research of additional antidotes.

Long-term skeletal muscle mitochondrial dysfunction is associated with hypermetabolism in severely burned children

Science.gov (United States)

The long-term impact of burn trauma on skeletal muscle bioenergetics remains unknown. Here, we determined respiratory capacity and function of skeletal muscle mitochondria in healthy individuals and in burn victims for up to two years post-injury. Biopsies were collected from the m. vastus lateralis...

Mitochondrial respiratory capacity remains stable despite a comprehensive and sustained increase in insulin sensitivity in obese patients undergoing gastric bypass surgery

DEFF Research Database (Denmark)

Lund, M T; Larsen, S; Hansen, M

2018-01-01

will correlate with a corresponding change in mitochondrial respiratory capacity over the same time period. METHODS: Insulin sensitivity was evaluated using the hyperinsulinaemic-euglycaemic clamp technique, and skeletal muscle mitochondrial respiratory capacity was evaluated by high-resolution respirometry...

Comparison of the Hamstring Muscle Activity and Flexion-Relaxation Ratio between Asymptomatic Persons and Computer Work-related Low Back Pain Sufferers.

Science.gov (United States)

Kim, Min-Hee; Yoo, Won-Gyu

2013-05-01

[Purpose] The purpose of this study was to compare the hamstring muscle (HAM) activities and flexion-relaxation ratios of an asymptomatic group and a computer work-related low back pain (LBP) group. [Subjects] For this study, we recruited 10 asymptomatic computer workers and 10 computer workers with work-related LBP. [Methods] We measured the RMS activity of each phase (flexion, full-flexion, and re-extension phase) of trunk flexion and calculated the flexion-relaxation (FR) ratio of the muscle activities of the flexion and full-flexion phases. [Results] In the computer work-related LBP group, the HAM muscle activity increased during the full-flexion phase compared to the asymptomatic group, and the FR ration was also significantly higher. [Conclusion] We thought that prolonged sitting of computer workers might cause the change in their HAM muscle activity pattern.

Aerobic fitness in patients with fibrositis. A controlled study of respiratory gas exchange and 133-xenon clearance from exercising muscle

International Nuclear Information System (INIS)

Bennett, R.M.; Clark, S.R.; Goldberg, L.; Nelson, D.; Bonafede, R.P.; Porter, J.; Specht, D.

1989-01-01

Aerobic fitness was evaluated in 25 women with fibrositis, by having them exercise to volitional exhaustion on an electronically braked cycle ergometer. Compared with published standards, greater than 80% of the fibrositis patients were not physically fit, as assessed by maximal oxygen uptake. Compared with matched sedentary controls, fibrositis patients accurately perceived their level of exertion in relation to oxygen consumption and attained a similar level of lactic acidosis, as assessed by their respiratory quotient and ventilatory threshold. Exercising muscle blood flow was estimated by 133-xenon clearance in a subgroup of 16 fibrositis patients and compared with that in 16 matched sedentary controls; the fibrositis patients exhibited reduced 133-xenon clearance. These results indicate a need to include aerobic fitness as a matched variable in future controlled studies of fibrositis and suggest that the detraining phenomenon may be of relevance to the etiopathogenesis of the disease

Respiratory insufficiency with preserved diaphragmatic function in amyotrophic lateral sclerosis.

Science.gov (United States)

Yamauchi, Rika; Imai, Tomihiro; Tsuda, Emiko; Hozuki, Takayoshi; Yamamoto, Daisuke; Shimohama, Shun

2014-01-01

We performed a longitudinal study to elucidate the correlation between respiratory insufficiency and respiratory biomarkers, including diaphragmatic compound muscle action potential (DCMAP), at the initiation of noninvasive ventilation (NIV) in patients with amyotrophic lateral sclerosis (ALS). The patients were assessed at least every six months. Additional assessments were performed at the start of respiratory therapy when the patients met the criteria for the initiation of NIV. Each assessment consisted of a full neurological examination, a phrenic nerve conduction study, respiratory function tests, and nocturnal pulsed oximetry. We enrolled 43 patients with either definite or probable ALS as defined by the revised El Escorial criteria. The patients were divided into two groups according to the timing of the initiation of respiratory therapy. Seventeen patients (group A) met the criteria for NIV initiation when their DCMAP remained normal. Twenty-six patients (group B) met the criteria when their DCMAP decreased below normal limits. Although respiratory function parameters were significantly worse in group B compared with group A at NIV initiation, more than 80% of the patients in both groups developed nocturnal desaturation during sleep. DCMAP is not always a reliable indicator for determining the optimal timing for NIV initiation during the progression of respiratory insufficiency in ALS. Physicians should be aware of the risk of respiratory insufficiency during sleep in patients with ALS.

Rehabilitation of patients admitted to a respiratory intensive care unit.

Science.gov (United States)

Nava, S

1998-07-01

Pulmonary rehabilitation has been shown to be of benefit to clinically stable patients with chronic obstructive pulmonary disease (COPD). This study examined the effect of pulmonary rehabilitation on some physiologic variables in COPD patients recovering from an episode of acute respiratory failure. A prospective, randomized study. A respiratory intensive care unit (RICU). Eighty COPD patients recovering from an episode of acute respiratory failure were randomized in a 3:1 fashion to receive stepwise pulmonary rehabilitation (group A, n=60 patients) or standard medical therapy (group B, n=20 patients). Improvements in exercise tolerance, sense of breathlessness, respiratory muscle function, and pulmonary function test values were measured, respectively, by exercise capacity (6-minute walking distance [6MWD]), dyspnea score (Visual Analog Scale [VAS]), maximal inspiratory pressure (MIP), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC). Group A received pulmonary rehabilitation that consisted of passive mobilization (step I), early deambulation (step II), respiratory and lower skeletal muscle training (step III), and if the patients were able, complete lower extremity training on a treadmill (step IV). Group B received standard medical therapy plus a basic deambulation program. Sixty-one of 80 patients were mechanically ventilated at admission to the unit and most of them were bedridden. Twelve of the 60 group A patients and 4 of the 20 group B patients died during their RICU stay, and 9 patients required invasive mechanical ventilation at home after their discharge. The total length of RICU stay was 38+/-14 days for patients in group A versus 33.2+/-11 days for those in group B. Most patients from both groups regained the ability to walk, either unaided or aided. At discharge, 6 MWD results were significantly improved (p respiratory failure and who, in most cases, required mechanical ventilation benefited from comprehensive early

Hyperventilation of pregnancy presenting with flaccid quadriparesis due to hypokalaemia secondary to respiratory alkalosis.

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Santra, Gouranga; Paul, Rudrajit; Das, Shubhabrata; Pradhan, Sourav

2014-06-01

Hyperventilation in pregnancy is a cause of chronic respiratory alkalosis. Alkalosis either metabolic or respiratory may cause intracellular shift of potassium ions that may lead to hypokalaemia. However, the resultant hypokalaemia in respiratory alkalosis is usually mild and does not cause much clinical features. A five-months-pregnant female of the age 25 years presented with sudden onset flaccid weakness of both lower limbs associated with thigh muscle pain followed by weakness of both upper limbs within three days. Subsequent investigation revealed severe hypokalaemia due to acute exacerbation of chronic respiratory alkalosis secondary to hyperventilation of pregnancy, other causes of hypokalaemia being ruled out. Respiratory alkalosis causes tetany and other clinical manifestations. But hypokalaemia and such weakness is rarely found. Thisis probably the first report of this type from India.

Manual muscle testing: a method of measuring extremity muscle strength applied to critically ill patients.

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Ciesla, Nancy; Dinglas, Victor; Fan, Eddy; Kho, Michelle; Kuramoto, Jill; Needham, Dale

2011-04-12

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge. Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. (7, 8) This video demonstrates a protocol for MMT, which has been taught to ≥ 43 research staff who have performed >800 assessments on >280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale. Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. (1,2).

Muscle strength, working capacity and effort in patients with fibromyalgia

DEFF Research Database (Denmark)

Nørregaard, J; Bülow, P M; Lykkegaard, J J

1997-01-01

exercise capacity, work status and psychometric scoring (SCL-90-R) were correlated. The fibromyalgia patients exhibited significant reduction in voluntary muscle strength of the knee and elbow, flexors and extensors in the order of 20-30%. However, the coefficient of variation was higher among patients......, thus indicating lower effort. The physical performance during an ergometer test corresponded to a maximal oxygen consumption of 21 ml/kg-1 x min-1. The maximal increase in heart rate was only 63% (44-90%) of the predicted increase. Degree of effort or physical capacity did not correlate to psychometric...... scores. Work status was related to psychometric scoring, but not to physical capacity or effort. In conclusion, we found a low degree of effort but near normal physical capacity in the fibromyalgia patients....

Toluene inducing acute respiratory failure in a spray paint sniffer.

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Peralta, Diego P; Chang, Aymara Y

2012-01-01

Toluene, formerly known as toluol, is an aromatic hydrocarbon that is widely used as an industrial feedstock and as a solvent. Like other solvents, toluene is sometimes also used as an inhalant drug for its intoxicating properties. It has potential to cause multiple effects in the body including death. I report a case of a 27-year-old male, chronic spray paint sniffer, who presented with severe generalized muscle weakness and developed acute respiratory failure requiring ventilatory support. Toluene toxicity was confirmed with measurement of hippuric acid of 8.0 g/L (normal <5.0 g/L). Acute respiratory failure is a rare complication of chronic toluene exposure that may be lethal if it is not recognized immediately. To our knowledge, this is the second case of acute respiratory failure due to toluene exposure.

Diaphragm remodeling and compensatory respiratory mechanics in a canine model of Duchenne muscular dystrophy.

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Mead, A F; Petrov, M; Malik, A S; Mitchell, M A; Childers, M K; Bogan, J R; Seidner, G; Kornegay, J N; Stedman, H H

2014-04-01

Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.

Cerium oxide nanozyme modulate the ‘exercise’ redox biology of skeletal muscle

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Arya, Aditya; Sethy, Niroj Kumar; Gangwar, Anamika; Bhargava, Neelima; Dubey, Amarish; Roy, Manas; Srivastava, Gaurav; Singh, Sushil Kumar; Das, Mainak; Bhargava, Kalpana

2017-05-01

‘Exercise’ is a double-edged sword for the skeletal muscle. Small amount of ROS generated during mild exercise, is essential for normal force generation; whereas large quantity of ROS generated during intense exercise, may cause contractile dysfunction, resulting in muscle weakness and fatigue. One of the key question in skeletal muscle physiology is ‘could antioxidant therapy improve the skeletal muscle endurance? A question, which has resulted in contradictory experimental findings till this date. This work has addressed this ‘very question’ using a synthetic, inorganic, antioxidant nano-material viz., ‘cerium oxide nanozyme’ (CON). It has been introduced in the rat by intramuscular injection, and the skeletal muscle endurance has been evaluated. Intramuscular injections of CON, concurrent with exercise, enhanced muscle mass, glycogen and ATP content, type I fiber ratio, thus resulting in significantly higher muscle endurance. Electron microscope studies confirmed the presence of CON in the vicinity of muscle mitochondria. There was an increase in the number and size of the muscle mitochondria in the CON treated muscle, following exercise, as compared to the untreated group with only exercised muscle. Quantitative proteomics data and subsequent biological network analysis studies, identified higher levels of oxidative phosphorylation, TCA cycle output and glycolysis in CON supplemented exercised muscle over only exercised muscle. This was further associated with significant increase in the mitochondrial respiratory capacity and muscle contraction, primarily due to higher levels of electron transport chain proteins like NDUFA9, SDHA, ATP5B and ATP5D, which were validated by real-time PCR and western blotting. Along with this, persistence of CON in muscle was evaluated with ICP-MS analysis, which revealed clearance of the particles after 90 d, without exhibiting any inflammation or adverse affects on the health of the experimental animals. Thus a

Electromyography-Guided Botulinum Toxin Injection Into the Cricothyroid Muscles in Bilateral Vocal Fold Abductor Paralysis

OpenAIRE

Sahin, Mustafa; Aydogdu, Ibrahim; Akyildiz, Serdar; Erdinc, Munevver; Ozturk, Kerem; Ogut, Fatih

2016-01-01

Objectives Bilateral vocal fold abductor paralysis (BVFAP) both deteriorates quality of life and may cause life-threatening respiratory problems. The aim of this study was to reduce respiratory symptoms in BVFAP patients using cricothyroid (CT) botulinum toxin (BTX) injection. Methods Before and 2 weeks and 4 months after bilateral BTX injection into the CT muscles under electromyography; alterations in respiratory, acoustic, aerodynamic and quality of life parameters were evaluated in BVFAP ...

Effects of inspiratory muscle training on dynamic hyperinflation in patients with COPD

Directory of Open Access Journals (Sweden)

Petrovic M

2012-11-01

Full Text Available Milos Petrovic,1 Michael Reiter,2 Harald Zipko,3 Wolfgang Pohl,1 Theodor Wanke11Pulmonary Department and Karl Landsteiner Institute for Clinical and Experimental Pulmology, Hietzing Hospital, Vienna, Austria; 2Department of Respiratory and Critical Care Medicine, Otto Wagner Hospital, Vienna, Austria; 3FH Campus Vienna, University of Applied Sciences – Health Department, Vienna, AustriaAbstract: Dynamic hyperinflation has important clinical consequences in patients with chronic obstructive pulmonary disease (COPD. Given that most of these patients have respiratory and peripheral muscle weakness, dyspnea and functional exercise capacity may improve as a result of inspiratory muscle training (IMT. The aim of the study was to analyze the effects of IMT on exercise capacity, dyspnea, and inspiratory fraction (IF during exercise in patients with COPD. Daily inspiratory muscle strength and endurance training was performed for 8 weeks in 10 patients with COPD GOLD II and III. Ten patients with COPD II and III served as a control group. Maximal inspiratory pressure (Pimax and endurance time during resistive breathing maneuvers (tlim served as parameter for inspiratory muscle capacity. Before and after training, the patients performed an incremental symptom limited exercise test to maximum and a constant load test on a cycle ergometer at 75% of the peak work rate obtained in the pretraining incremental test. ET was defined as the duration of loaded pedaling. Following IMT, there was a statistically significant increase in inspiratory muscle performance of the Pimax from 7.75 ± 0.47 to 9.15 ± 0.73 kPa (P < 0.01 and of tlim from 348 ± 54 to 467 ± 58 seconds (P < 0.01. A significant increase in IF, indicating decreased dynamic hyperinflation, was observed during both exercise tests. Further, the ratio of breathing frequency to minute ventilation (bf/V'E decreased significantly, indicating an improved breathing pattern. A significant decrease in

The respiratory mass spectrometer

International Nuclear Information System (INIS)

Mostert, J.W.

1983-01-01

The high degree of technical perfection of the respiratory mass spectrometer has rendered the instrument feasible for routine monitoring of anesthetized patients. It is proposed that the difference between inspired and expired oxygen tension in mm Hg be equated with whole body oxygen consumption in ml/min/M 2 body-surface area at STPD, by the expedient of multiplying tension-differences by a factor of 2. Years of experience have confirmed the value of promptly recognizing sudden drops in this l/E tension difference below 50 mm Hg indicative of metabolic injury from hypovolemia or respiratory depression. Rises in l/E tension-differences were associated with shivering as well as voluntary muscle activity. Tension differences of less than 25 mm Hg (equated with a whole-body O 2 consumption of less than 50 ml O 2 /min/M 2 ) occurred in a patient in the sitting position for posterior fossa exploration without acidosis, hypoxia or hypotension for several hours prior to irreversible cardiac arrest. The value of clinical monitoring by mass spectrometry is especially impressive in open-heart surgery

Evaluation of Respiratory Muscle Strength in the Acute Phase of Stroke: The Role of Aging and Anthropometric Variables.

Science.gov (United States)

Luvizutto, Gustavo José; Dos Santos, Maria Regina Lopes; Sartor, Lorena Cristina Alvarez; da Silva Rodrigues, Josiela Cristina; da Costa, Rafael Dalle Molle; Braga, Gabriel Pereira; de Oliveira Antunes, Letícia Cláudia; Souza, Juli Thomaz; de Carvalho Nunes, Hélio Rubens; Bazan, Silméia Garcia Zanati; Bazan, Rodrigo

2017-10-01

During hospitalization, stroke patients are bedridden due to neurologic impairment, leading to loss of muscle mass, weakness, and functional limitation. There have been few studies examining respiratory muscle strength (RMS) in the acute phase of stroke. This study aimed to evaluate the RMS of patients with acute stroke compared with predicted values and to relate this to anthropometric variables, risk factors, and neurologic severity. This is a cross-sectional study in the acute phase of stroke. After admission, RMS was evaluated by maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP); anthropometric data were collected; and neurologic severity was evaluated by the National Institutes of Health Stroke Scale. The analysis of MIP and MEP with predicted values was performed by chi-square test, and the relationship between anthropometric variables, risk factors, and neurologic severity was determined through multiple linear regression followed by residue analysis by the Shapiro-Wilk test; P < .05 was considered statistically significant. In the 32 patients studied, MIP and MEP were reduced when compared with the predicted values. MIP declined significantly by 4.39 points for each 1 kg/m 2 increase in body mass index (BMI), and MEP declined significantly by an average of 3.89 points for each 1 kg/m 2 increase in BMI. There was no statistically significant relationship between MIP or MEP and risk factors, and between MIP or MIP and neurologic severity in acute phase of stroke. There is a reduction of RMS in the acute phase of stroke, and RMS was lower in individuals with increased age and BMI. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Hypokalemic paralysis and respiratory failure due to excessive intake of licorice syrup

Directory of Open Access Journals (Sweden)

Mehmet Oguzhan Ay

2014-04-01

Full Text Available Licorice is the root of Glycyrrhiza glabra, which has a herbal ingredient, glycyrrhizic acid. Excessive intake of licorice may cause a hypermineralocorticoidism-like syndrome characterized by sodium and water retention, hypokalemia, hypertension, metabolic alkalosis, low-renin activity, and hypoaldosteronism. In this paper, an 34 years old man who admitted to the emergency department with respiratory failure and marked muscle weakness of all extremities that progressed to paralysis after excessive intake of licorice syrup was presented. It was aimed to draw attention to the necessity of questioning whether there is excessive intake of licorice or not in patients who admitted to emergency department with paralysis and dyspnea. Plasma potassium concentration of the patient was 1.4 mmol/L. The patient\\'s respiratory distress and loss of muscle strength recovered completely after potassium replacement. [Cukurova Med J 2014; 39(2.000: 387-391

Increased mitochondrial energy efficiency in skeletal muscle after long-term fasting: its relevance to animal performance.

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Bourguignon, Aurore; Rameau, Anaïs; Toullec, Gaëlle; Romestaing, Caroline; Roussel, Damien

2017-07-01

In the final stage of fasting, skeletal muscle mass and protein content drastically decrease when the maintenance of efficient locomotor activity becomes crucial for animals to reactivate feeding behaviour and survive a very long period of starvation. As mitochondrial metabolism represents the main physiological link between the endogenous energy store and animal performance, the aim of this study was to determine how a very long, natural period of fasting affected skeletal muscle mitochondrial bioenergetics in king penguin ( Aptenodytes patagonicus ) chicks. Rates of mitochondrial oxidative phosphorylation were measured in pectoralis permeabilized fibres and isolated mitochondria. Mitochondrial ATP synthesis efficiency and the activities of respiratory chain complexes were measured in mitochondria isolated from pectoralis muscle. Results from long-term (4-5 months) naturally fasted chicks were compared with those from short-term (10 day) fasted birds. The respiratory activities of muscle fibres and isolated mitochondria were reduced by 60% and 45%, respectively, on average in long-term fasted chicks compared with short-term fasted birds. Oxidative capacity and mitochondrial content of pectoralis muscle were lowered by long-term fasting. Bioenergetic analysis of pectoralis muscle also revealed that mitochondria were, on average, 25% more energy efficient in the final stage of fasting (4-5 months) than after 10 days of fasting (short-term fasted birds). These results suggest that the strong reduction in respiratory capacity of pectoralis muscle was partly alleviated by increased mitochondrial ATP synthesis efficiency. Such oxidative phosphorylation optimization can impact animal performance, e.g. the metabolic cost of locomotion or the foraging efficiency. © 2017. Published by The Company of Biologists Ltd.

Respiratory Protection Behavior and Respiratory Indices among Poultry House Workers on Small, Family-Owned Farms in North Carolina: A Pilot Project.

Science.gov (United States)

Kearney, Gregory D; Gallagher, Barbara; Shaw, Robert

2016-01-01

The aim of this pilot study was to evaluate respiratory behavior and respiratory indices of poultry workers on family-owned, poultry farms with 10 or less employees in North Carolina. A field study was conducted to collect data on participants (N = 24) using spirometry, fractional exhaled nitric oxide (Feno), and an interviewer-administered questionnaire. The majority of workers (76%) ranked respiratory protection as being important, yet 48% reported never or rarely wearing respiratory protection when working in dusty conditions. A large percent of workers reported eye (55%) and nasal (50%) irritation and dry cough (50%). On average, pulmonary lung function and Feno tests were normal among nonsmokers. In bivariate analysis, significant associations were identified between working 7 days on the farm (P = .01), with eye irritation, and working 5 or fewer years in poultry farming (P = .01). Poultry workers on family-owned farms spend a considerable amount of work time in poultry houses and report acute respiratory-related health symptoms. Administrative controls among small, family-owned poultry farms are necessary to improve and promote safety and health to its employees.

Chronic Dosing with Membrane Sealant Poloxamer 188 NF Improves Respiratory Dysfunction in Dystrophic Mdx and Mdx/Utrophin-/- Mice.

Directory of Open Access Journals (Sweden)

Bruce E Markham

Full Text Available Poloxamer 188 NF (national formulary (NF grade of P-188 improves cardiac muscle function in the mdx mouse and golden retriever muscular dystrophy models. However in vivo effects on skeletal muscle have not been reported. We postulated that P-188 NF might protect diaphragm muscle membranes from contraction-induced injury in mdx and mdx/utrophin-/- (dko muscular dystrophy models. In the first study 7-month old mdx mice were treated for 22 weeks with subcutaneous (s.c. injections of saline or P-188 NF at 3 mg/Kg. In the second, dkos were treated with saline or P-188 NF (1 mg/Kg for 8 weeks beginning at age 3 weeks. Prednisone was the positive control in both studies. Respiratory function was monitored using unrestrained whole body plethysmography. P-188 NF treatment affected several respiratory parameters including tidal volume/BW and minute volume/BW in mdx mice. In the more severe dko model, P-188 NF (1 mg/Kg significantly slowed the decline in multiple respiratory parameters compared with saline-treated dko mice. Prednisone's effects were similar to those seen with P-188 NF. Diaphragms from P-188 NF or prednisone treated mdx and dko mice showed signs of muscle fiber protection including less centralized nuclei, less variation in fiber size, greater fiber density, and exhibited a decreased amount of collagen deposition. P-188 NF at 3 mg/Kg s.c. also improved parameters of systolic and diastolic function in mdx mouse hearts. These results suggest that P-188 NF may be useful in treating respiratory and cardiac dysfunction, the leading causes of death in Duchenne muscular dystrophy patients.

[Muscle biopsy in children: Usefulness in 2012].

Science.gov (United States)

Cuisset, J-M; Maurage, C-A; Carpentier, A; Briand, G; Thévenon, A; Rouaix, N; Vallée, L

2013-01-01

Muscle biopsy is a mainstay diagnostic tool for investigating neuromuscular disorders in children. We report the yield of pediatric muscle biopsy in a population of 415 children by a retrospective study of 419 biopsies performed between 1/01/2000 and 31/12/2009 in a neuropediatric department, including mitochondrial respiratory chain analysis for 87 children. Two hundred and fifty-five biopsies were from boys (61%) 164 from girls (39%). Their mean age at biopsy was 6.5years; 155 (37%) biopsies were obtained before the child was 5years old. Final histopathological diagnoses were: congenital myopathy (n=193, including 15 structural congenital myopathies); progressive muscular dystrophy (n=75 [18%] including 57 dystrophinopathies); congenital muscular dystrophy (n=17, including six primary merosinopathies); dermatomyositis (n=11); spinal muscular atrophy (n=9, including six atypical spinal muscular atrophies); metabolic myopathy (n=32, including 19 mitochondrial myopathies); encephalomyopathy (n=53 [13%], including 27 with a mitochondrial respiratory chain defect). Pathological diagnosis remained undetermined in 16 cases. In 184 patients (44%), the muscle biopsy revealed specific histopathological anomalies (dystrophic process; specific ultrastructural abnormalities; perifascicular atrophy; neurogenic atrophy; metabolic anomalies) enabling a precise etiological diagnosis. For 85% of progressive muscular dystrophies, the biopsy resulted in a genetic diagnosis after identification of the protein defect. In 15% of the congenital myopathies, histopathological anomalies focused attention on one or several genes. Concerning dystrophinopathies, quantification of dystrophin deficiency on the biopsy specimen contributed to the definition of the clinical phenotype: Duchenne, or Becker. In children with a myopathy, muscle biopsy is often indispensable to establish the etiological diagnosis. Based on the results from this series, muscle biopsy can provide a precise

Severe metabolic alkalosis, hypokalemia, and respiratory acidosis induced by the Chinese herbal medicine yokukansan in an elderly patient with muscle weakness and drowsiness.

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Yamada, Shunsuke; Tokumoto, Masanori; Kansui, Yasuo; Wakisaka, Yoshinobu; Uchizono, Yuji; Tsuruya, Kazuhiko; Ooboshi, Hiroaki

2013-05-01

Yokukansan is a Chinese herbal medicine containing licorice that has been shown to alleviate the behavioral and psychological symptoms of Alzheimer's disease, with few adverse effects. Increasing numbers of patients with Alzheimer's disease in Japan are now being treated with this drug. However, yokukansan should be used with caution because of its potential to induce pseudoaldosteronism through the inhibition of 11-beta-hydroxysteroid dehydrogenase type 2, which metabolizes cortisol into cortisone. We present the case of an 88-year-old woman with a history of Alzheimer's disease who was transferred to our emergency department because of drowsiness, anorexia, and muscle weakness. Her blood pressure was 168/90 mmHg. Laboratory data showed serum potassium of 1.9 mmol/l, metabolic alkalosis (pH 7.54; HCO 3 - , 50.5 mmol/l; chloride, 81 mmol/l; sodium, 140 mmol/l), and respiratory disorders (pCO 2 , 60.5 mmHg; pO 2 , 63.8 mmHg). Plasma renin activity and aldosterone concentration were suppressed, and urinary potassium excretion was 22 mmol/l (calculated transtubular potassium gradient 12.9). An electrocardiogram showed flat T-waves and U-waves with ventricular premature contractions. Echocardiography denied volume depletion. Medical interview disclosed that she had been treated with a Chinese herbal medicine (yokukansan) containing licorice. The final diagnosis was pseudoaldosteronism and respiratory acidosis induced by licorice. Hypokalemia, metabolic alkalosis, and respiratory acidosis all subsided shortly after the discontinuation of yokukansan and initiation of intravenous potassium replacement. This case highlights the need for nephrologists to consider the possible involvement of Chinese herbal medicines, including yokukansan, when they encounter hypokalemia in elderly patients.

Gender differences in respiratory symptoms-does occupation matter?

Science.gov (United States)

Dimich-Ward, Helen; Camp, Patricia G; Kennedy, Susan M

2006-06-01

Little attention has been given to gender differences in respiratory health, particularly in occupational settings. The purpose of this paper was to evaluate gender differences in respiratory morbidity based on surveys of hospitality workers, radiographers, and respiratory therapists. Data were available from mail surveys of 850 hospitality industry workers (participation rate 73.9%; 52.6% female), 586 radiographers (participation rate 63.6%; 85% female), and 275 respiratory therapists (participation rate 64.1%; 58.6% female). Cross-tabulations by gender were evaluated by chi(2) analysis and logistic regression with adjustment for personal and work characteristics. Women consistently had greater respiratory morbidity for symptoms associated with shortness of breath, whereas men usually had a higher prevalence of phlegm. There were few differences in work exposures apart from perception of exposure to ETS among hospitality workers. Gender differences in symptoms were often reduced after adjustment for personal and work characteristics but for respiratory therapists there were even greater gender disparities for asthma attack and breathing trouble. Population health findings of elevated symptoms among women were only partially supported by these occupational respiratory health surveys. The influence of differential exposures and personal factors should be considered when interpreting gender differences in health outcomes.

Gender differences in respiratory symptoms-Does occupation matter?

International Nuclear Information System (INIS)

Dimich-Ward, Helen; Camp, Patricia G.; Kennedy, Susan M.

2006-01-01

Little attention has been given to gender differences in respiratory health, particularly in occupational settings. The purpose of this paper was to evaluate gender differences in respiratory morbidity based on surveys of hospitality workers, radiographers, and respiratory therapists. Data were available from mail surveys of 850 hospitality industry workers (participation rate 73.9%; 52.6% female), 586 radiographers (participation rate 63.6%; 85% female), and 275 respiratory therapists (participation rate 64.1%; 58.6% female). Cross-tabulations by gender were evaluated by χ 2 analysis and logistic regression with adjustment for personal and work characteristics. Women consistently had greater respiratory morbidity for symptoms associated with shortness of breath, whereas men usually had a higher prevalence of phlegm. There were few differences in work exposures apart from perception of exposure to ETS among hospitality workers. Gender differences in symptoms were often reduced after adjustment for personal and work characteristics but for respiratory therapists there were even greater gender disparities for asthma attack and breathing trouble. Population health findings of elevated symptoms among women were only partially supported by these occupational respiratory health surveys. The influence of differential exposures and personal factors should be considered when interpreting gender differences in health outcomes

Microvascular oxygen partial pressure during hyperbaric oxygen in diabetic rat skeletal muscle.

Science.gov (United States)

Yamakoshi, Kohei; Yagishita, Kazuyoshi; Tsuchimochi, Hirotsugu; Inagaki, Tadakatsu; Shirai, Mikiyasu; Poole, David C; Kano, Yutaka

2015-12-15

Hyperbaric oxygen (HBO) is a major therapeutic treatment for ischemic ulcerations that perforate skin and underlying muscle in diabetic patients. These lesions do not heal effectively, in part, because of the hypoxic microvascular O2 partial pressures (PmvO2 ) resulting from diabetes-induced cardiovascular dysfunction, which alters the dynamic balance between O2 delivery (Q̇o2) and utilization (V̇o2) rates. We tested the hypothesis that HBO in diabetic muscle would exacerbate the hyperoxic PmvO2 dynamics due, in part, to a reduction or slowing of the cardiovascular, sympathetic nervous, and respiratory system responses to acute HBO exposure. Adult male Wistar rats were divided randomly into diabetic (DIA: streptozotocin ip) and healthy (control) groups. A small animal hyperbaric chamber was pressurized with oxygen (100% O2) to 3.0 atmospheres absolute (ATA) at 0.2 ATA/min. Phosphorescence quenching techniques were used to measure PmvO2 in tibialis anterior muscle of anesthetized rats during HBO. Lumbar sympathetic nerve activity (LSNA), heart rate (HR), and respiratory rate (RR) were measured electrophysiologically. During the normobaric hyperoxia and HBO, DIA tibialis anterior PmvO2 increased faster (mean response time, CONT 78 ± 8, DIA 55 ± 8 s, P < 0.05) than CONT. Subsequently, PmvO2 remained elevated at similar levels in CONT and DIA muscles until normobaric normoxic recovery where the DIA PmvO2 retained its hyperoxic level longer than CONT. Sympathetic nervous system and cardiac and respiratory responses to HBO were slower in DIA vs. CONT. Specifically the mean response times for RR (CONT: 6 ± 1 s, DIA: 29 ± 4 s, P < 0.05), HR (CONT: 16 ± 1 s, DIA: 45 ± 5 s, P < 0.05), and LSNA (CONT: 140 ± 16 s, DIA: 247 ± 34 s, P < 0.05) were greater following HBO onset in DIA than CONT. HBO treatment increases tibialis anterior muscle PmvO2 more rapidly and for a longer duration in DIA than CONT, but not to a greater level. Whereas respiratory, cardiovascular

Respiratory guiding system for respiratory motion management in respiratory gated radiotherapy

International Nuclear Information System (INIS)

Kang, Seong Hee; Kim, Dong Su; Kim, Tae Ho; Suh, Tae Suk

2013-01-01

Respiratory guiding systems have been shown to improve the respiratory regularity. This, in turn, improves the efficiency of synchronized moving aperture radiation therapy, and it reduces the artifacts caused by irregular breathing in imaging techniques such as four-dimensional computed tomography (4D CT), which is used for treatment planning in RGRT. We have previously developed a respiratory guiding system that incorporates an individual-specific guiding waveform, which is easy to follow for each volunteer, to improve the respiratory regularity. The present study evaluates the application of this system to improve the respiratory regularity for respiratory-gated radiation therapy (RGRT). In this study, we evaluated the effectiveness of an in-house-developed respiratory guiding system incorporating an individual specific guiding waveform to improve the respiratory regularity for RGRT. Most volunteers showed significantly less residual motion at each phase during guided breathing owing to the improvement in respiratory regularity. Therefore, the respiratory guiding system can clearly reduce the residual, or respiratory, motion in each phase. From the result, the CTV and the PTV margins during RGRT can be reduced by using the respiratory guiding system, which reduces the residual motions, thus improving the accuracy of RGRT

Assessment of work-related muscle strain by using surface EMG during test contractions interposed between work periods of simulateted mushroom picking

DEFF Research Database (Denmark)

Ohashi, Jun-Ya; Blangsted, Anne Katrine; Nielsen, Pernille Kofoed

2010-01-01

Surface electromyograms(EMG) during test contractions (TCs) were studied to assess the muscle strain in simulated mushroom picking. Additionally, the duration of the TC for the effective assessment was investigated. Nine female subjects performed standardized shoulder abduction and a stooped...... posture for one minute as TCs. Each experiment consisted of a 60-min rest, three work periods (W1-W3), a 30-min rest, and two work periods (W4 and W5) separated by a 30-min rest period. The duration of each work period was about 20 min. A total of 18 TCs was performed between the work periods and every 10...

Respiratory Illness and Allergy Related to Work and Home Environment among Commercial Pilots.

Science.gov (United States)

Fu, Xi; Lindgren, Torsten; Wieslander, Gunilla; Janson, Christer; Norbäck, Dan

2016-01-01

The aim was to study associations between work and home environment and prevalence and incidence of respiratory health and a history of atopy in a 3-y cohort of commercial pilots. A questionnaire was mailed in 1997 to all pilots in a Scandinavian airline company (N = 622); 577 (93%) participated. The same questionnaire was sent to the participants 3 years later, 436 participated (76%). There were questions on asthma, respiratory symptoms and infections, allergies, the cabin environment, psychosocial environment and the home environment. Associations were analyzed by multiple logistic regression, calculating odds ratios (OR) with 95% confidence intervals (95%CI). The incidence of doctors' diagnosed asthma and atopy were 2.4 and 16.6 per 1000 person years, respectively. Pilots changing type of flight during follow-up got more airway infections (OR = 11.27; 95% CI 2.39-53.14). Those reporting decreased work control (OR = 1.85; 95% CI 1.03-3.31 for 1 unit change) and those with environmental tobacco smoke (ETS) at home (OR = 3.73; 95% CI 1.09-12.83) had a higher incidence of atopy during follow up. Dampness or mould at home was associated with a higher prevalence of asthma symptoms (OR = 3.55; 95% CI 1.43-8.82) and airway infections (OR = 3.12 95% CI 1.27-7.68). Window pane condensation in winter at home, reported at baseline, was associated with increased incidence of asthma symptoms (OR = 4.14; 95% CI 1.32-12.97) and pilots living in newer buildings at baseline had a higher incidence of airway infections (OR = 5.23; 95% CI 1.43-19.10). In conclusion, lack of work control and ETS at home can be a risk factors for development of allergic symptoms in pilots. Window pane condensation at home can be a risk factor for incidence of asthma symptoms. Dampness and mould at home can be a risk factor for prevalence of asthma symptoms and airway infections and living in newer buildings can be a risk factor for incidence of airway infections.

On the mechanism by which dietary nitrate improves human skeletal muscle function

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Charles eAffourtit

2015-07-01

Full Text Available Inorganic nitrate is present at high levels in beetroot and celery, and in green leafy vegetables such as spinach and lettuce. Though long believed inert, nitrate can be reduced to nitrite in the human mouth and, further, under hypoxia and/or low pH, to nitric oxide. Dietary nitrate has thus been associated favourably with nitric-oxide-regulated processes including blood flow and energy metabolism. Indeed, the therapeutic potential of dietary nitrate in cardiovascular disease and metabolic syndrome – both ageing-related medical disorders – has attracted considerable recent research interest. We and others have shown that dietary nitrate supplementation lowers the oxygen cost of human exercise, as less respiratory activity appears to be required for a set rate of skeletal muscle work. This striking observation predicts that nitrate benefits the energy metabolism of human muscle, increasing the efficiency of either mitochondrial ATP synthesis and/or of cellular ATP-consuming processes. In this mini-review, we evaluate experimental support for the dietary nitrate effects on muscle bioenergetics and we critically discuss the likelihood of nitric oxide as the molecular mediator of such effects.

Muscle mitochondrial capacity exceeds maximal oxygen delivery in humans

DEFF Research Database (Denmark)

Boushel, Robert Christopher; Gnaiger, Erich; Calbet, Jose A L

2011-01-01

Across a wide range of species and body mass a close matching exists between maximal conductive oxygen delivery and mitochondrial respiratory rate. In this study we investigated in humans how closely in-vivo maximal oxygen consumption (VO(2) max) is matched to state 3 muscle mitochondrial respira...

Combined effect of repetitive work and cold on muscle function and fatigue.

Science.gov (United States)

Oksa, Juha; Ducharme, Michel B; Rintamäki, Hannu

2002-01-01

This study compared the effect of repetitive work in thermoneutral and cold conditions on forearm muscle electromyogram (EMG) and fatigue. We hypothesize that cold and repetitive work together cause higher EMG activity and fatigue than repetitive work only, thus creating a higher risk for overuse injuries. Eight men performed six 20-min work bouts at 25 degrees C (W-25) and at 5 degrees C while exposed to systemic (C-5) and local cooling (LC-5). The work was wrist flexion-extension exercise at 10% maximal voluntary contraction. The EMG activity of the forearm flexors and extensors was higher during C-5 (31 and 30%, respectively) and LC-5 (25 and 28%, respectively) than during W-25 (P forearm flexors at the end of W-25 was 15%. The corresponding values at the end of C-5 and LC-5 were 37% (P < 0.05 in relation to W-25) and 20%, respectively. Thus repetitive work in the cold causes higher EMG activity and fatigue than repetitive work in thermoneutral conditions.

29 CFR 1926.103 - Respiratory protection.

Science.gov (United States)

2010-07-01

... 29 Labor 8 2010-07-01 2010-07-01 false Respiratory protection. 1926.103 Section 1926.103 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1926.103 Respiratory protection. Note: The requirements applicable to construction work under this...

Effects of breathing exercises on lung capacity and muscle activities of elderly smokers

Science.gov (United States)

Jun, Hyun-Ju; Kim, Ki-Jong; Nam, Ki-Won; Kim, Chang-Heon

2016-01-01

[Purpose] Elderly smokers have a reduced chest diameter due to weakening of the respiratory muscles, and this results in decreased ventilation, leading to a vicious circle. Therefore, the present study investigated the effects of an intervention program to enhance the pulmonary function and muscle activity of elderly smokers. [Subjects and Methods] Participants were randomly assigned to one of two experimental groups or a control (CG) group. The experimental groups performed exercises three times per week for six weeks, whereas the CG performed no exercises. One of the experimental groups performed a Feedback Breathing Exercise (FBE) for 15 minutes, and the other repeated three sets of Balloon-Blowing Exercises (BBE) with sufficient rest of more than one minute between sets. [Results] In the experimental groups, FVC, FEV1/FVC, PEF and muscle activity of the rectus abdominis significantly improved after four weeks, but no significant differences were observed in FEV1 or VC after six weeks. [Conclusion] The results show that FBE and BBE improved the pulmonary functions of elderly smokers, demonstrating the potential benefits of the development of various training methods using balloons, and group programs, including recreational factors, for increasing respiratory muscles strength. PMID:27390394

Effects of breathing exercises on lung capacity and muscle activities of elderly smokers.

Science.gov (United States)

Jun, Hyun-Ju; Kim, Ki-Jong; Nam, Ki-Won; Kim, Chang-Heon

2016-06-01

[Purpose] Elderly smokers have a reduced chest diameter due to weakening of the respiratory muscles, and this results in decreased ventilation, leading to a vicious circle. Therefore, the present study investigated the effects of an intervention program to enhance the pulmonary function and muscle activity of elderly smokers. [Subjects and Methods] Participants were randomly assigned to one of two experimental groups or a control (CG) group. The experimental groups performed exercises three times per week for six weeks, whereas the CG performed no exercises. One of the experimental groups performed a Feedback Breathing Exercise (FBE) for 15 minutes, and the other repeated three sets of Balloon-Blowing Exercises (BBE) with sufficient rest of more than one minute between sets. [Results] In the experimental groups, FVC, FEV1/FVC, PEF and muscle activity of the rectus abdominis significantly improved after four weeks, but no significant differences were observed in FEV1 or VC after six weeks. [Conclusion] The results show that FBE and BBE improved the pulmonary functions of elderly smokers, demonstrating the potential benefits of the development of various training methods using balloons, and group programs, including recreational factors, for increasing respiratory muscles strength.

Effects of pretension on work and power output of the muscle-tendon complex in dynamic elbow flexion.

Science.gov (United States)

Wakayama, Akinobu; Nagano, Akinori; Hay, Dean; Fukashiro, Senshi

2005-06-01

The purpose of the present study was to investigate the effects of pretension on work and power output of the muscle-tendon complex during dynamic elbow flexion under several submaximal and maximal conditions. The subjects were 10 healthy female students. Randomized trials from 0% to 100% maximal voluntary contraction (MVC) pretension (PT) at 60 degrees elbow flexion were conducted. After about 3 s of static PT, subjects maximally flexed the elbow joint to 90 degrees using a quick release method. The weight was individually selected for each subject to provide an optimal load for the development of maximal power. A Hill-type model was utilized to analyze the performance of the elbow muscle-tendon complex (MTC). PT 0, 30, 60 and 90% MVC data were used for comparison, and all data were expressed as the mean and standard deviation. Multiple paired comparisons between the value of PT 0% MVC and that of the other PT levels were performed post-hoc using Dunnett's method. The work of the series elastic component (SEC) increased gradually with the PT level because elastic energy was stored in the PT phase. However, the work of the contractile component (CC) decreased gradually with an increase in PT level. Moreover, the work of the MTC also decreased, closely related to the CC work decrement. The phenomenon of CC work decrement was caused by force depression and was not related to either the force-length or force-velocity relationships of the CC. EMG activity (agonist and antagonist) showed no significant differences. Muscle geometry changes or intracellular chemical shifts may have occurred in the PT phase.

The relationship of muscle perfusion and metabolism with cardiovascular variables before and after detomidine injection during propofol-ketamine anaesthesia in horses.

Science.gov (United States)

Edner, Anna; Nyman, Görel; Essén-Gustavsson, Birgitta

2002-10-01

To study in horses (1) the relationship between cardiovascular variables and muscle perfusion during propofol-ketamine anaesthesia, (2) the physiological effects of a single intravenous (IV) detomidine injection, (3) the metabolic response of muscle to anaesthesia, and (4) the effects of propofol-ketamine infusion on respiratory function. Prospective experimental study. Seven standardbred trotters, 5-12 years old, 416-581 kg. Anaesthesia was induced with intravenous (IV) guaifenesin and propofol (2 mg kg -1 ) and maintained with a continuous IV infusion of propofol (0.15 mg kg -1 minute -1 ) and ketamine (0.05 mg kg -1 minute -1 ) with horses positioned in left lateral recumbency. After 1 hour, detomidine (0.01 mg kg -1 ) was administered IV and 40-50 minutes later anaesthesia was discontinued. Cardiovascular and respiratory variables (heart rate, cardiac output, systemic and pulmonary artery blood pressures, respiratory rate, tidal volume, and inspiratory and expiratory O 2 and CO 2 ) and muscle temperature were measured at pre-determined times. Peripheral perfusion was measured continuously in the gluteal muscles and skin using laser Doppler flowmetry (LDF). Muscle biopsy samples from the left and right gluteal muscles were analysed for glycogen, creatine phosphate, creatine, adenine nucleotides, inosine monophosphate and lactate. Arterial blood was analysed for PO 2 , PCO 2 , pH, oxygen saturation and HCO 3 . Mixed venous blood was analysed for PO 2 , PCO 2 , pH, oxygen saturation, HCO 3 , cortisol, lactate, uric acid, hypoxanthine, xanthine, creatine kinase, creatinine, aspartate aminotransferase, electrolytes, total protein, haemoglobin, haematocrit and white blood cell count. Circulatory function was preserved during propofol-ketamine anaesthesia. Detomidine caused profound hypertension and bradycardia and decreased cardiac output and muscle perfusion. Ten minutes after detomidine injection muscle perfusion had recovered to pre-injection levels, although

Assessment and management of respiratory function in patients with Duchenne muscular dystrophy: current and emerging options

Science.gov (United States)

LoMauro, Antonella; D’Angelo, Maria Grazia; Aliverti, Andrea

2015-01-01

Duchenne muscular dystrophy (DMD) is an X-linked myopathy resulting in progressive weakness and wasting of all the striated muscles including the respiratory muscles. The consequences are loss of ambulation before teen ages, cardiac involvement and breathing difficulties, the main cause of death. A cure for DMD is not currently available. In the last decades the survival of patients with DMD has improved because the natural history of the disease can be changed thanks to a more comprehensive therapeutic approach. This comprises interventions targeted to the manifestations and complications of the disease, particularly in the respiratory care. These include: 1) pharmacological intervention, namely corticosteroids and idebenone that significantly reduce the decline of spirometric parameters; 2) rehabilitative intervention, namely lung volume recruitment techniques that help prevent atelectasis and slows the rate of decline of pulmonary function; 3) scoliosis treatment, namely steroid therapy that is used to reduce muscle inflammation/degeneration and prolong ambulation in order to delay the onset of scoliosis, being an additional contribution to the restrictive lung pattern; 4) cough assisted devices that improve airway clearance thus reducing the risk of pulmonary infections; and 5) non-invasive mechanical ventilation that is essential to treat nocturnal hypoventilation, sleep disordered breathing, and ultimately respiratory failure. Without any intervention death occurs within the first 2 decades, however, thanks to this multidisciplinary therapeutic approach life expectancy of a newborn with DMD nowadays can be significantly prolonged up to his fourth decade. This review is aimed at providing state-of-the-art methods and techniques for the assessment and management of respiratory function in DMD patients. PMID:26451113

Skeletal muscle mitochondrial respiration in AMPKa2 kinase dead mice

DEFF Research Database (Denmark)

Larsen, Steen; Kristensen, Jonas Møller; Stride, Nis

2012-01-01

AIM: To study if the phenotypical characteristics (exercise intolerance; reduced spontaneous activity) of the AMPKa2 kinase-dead (KD) mice can be explained by a reduced mitochondrial respiratory flux rates (JO(2) ) in skeletal muscle. Secondly, the effect of the maturation process on JO(2...

Fast-twitch glycolytic skeletal muscle is predisposed to age-induced impairments in mitochondrial function

DEFF Research Database (Denmark)

Jacobs, Robert A; Díaz, Víctor; Soldini, Lavinia

2013-01-01

The etiology of mammalian senescence is suggested to involve the progressive impairment of mitochondrial function; however, direct observations of age-induced alterations in actual respiratory chain function are lacking. Accordingly, we assessed mitochondrial function via high-resolution respirom......The etiology of mammalian senescence is suggested to involve the progressive impairment of mitochondrial function; however, direct observations of age-induced alterations in actual respiratory chain function are lacking. Accordingly, we assessed mitochondrial function via high......-resolution respirometry and mitochondrial protein expression in soleus, quadricep, and lateral gastrocnemius skeletal muscles, which represent type 1 slow-twitch oxidative muscle (soleus) and type 2 fast-twitch glycolytic muscle (quadricep and gastrocnemius), respectively, in young (10-12 weeks) and mature (74-76 weeks......) mice. Electron transport through mitochondrial complexes I and III increases with age in quadricep and gastrocnemius, which is not observed in soleus. Mitochondrial coupling efficiency during respiration through complex I also deteriorates with age in gastrocnemius and shows a tendency (p = .085...

Muscle physiology changes induced by every other day feeding and endurance exercise in mice: effects on physical performance.

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Elizabeth Rodríguez-Bies

Full Text Available Every other day feeding (EOD and exercise induce changes in cell metabolism. The aim of the present work was to know if both EOD and exercise produce similar effects on physical capacity, studying their physiological, biochemical and metabolic effects on muscle. Male OF-1 mice were fed either ad libitum (AL or under EOD. After 18 weeks under EOD, animals were also trained by using a treadmill for another 6 weeks and then analyzed for physical activity. Both, EOD and endurance exercise increased the resistance of animals to extenuating activity and improved motor coordination. Among the groups that showed the highest performance, AL and EOD trained animals, ALT and EODT respectively, only the EODT group was able to increase glucose and triglycerides levels in plasma after extenuating exercise. No high effects on mitochondrial respiratory chain activities or protein levels neither on coenzyme Q levels were found in gastrocnemius muscle. However, exercise and EOD did increase β-oxidation activity in this muscle accompanied by increased CD36 levels in animals fed under EOD and by changes in shape and localization of mitochondria in muscle fibers. Furthermore, EOD and training decreased muscle damage after strenuous exercise. EOD also reduced the levels of lipid peroxidation in muscle. Our results indicate that EOD improves muscle performance and resistance by increasing lipid catabolism in muscle mitochondria at the same time that prevents lipid peroxidation and muscle damage.

Relação da função muscular respiratória e de membros inferiores de idosos comunitários com a capacidade funcional avaliada por teste de caminhada Relationship between functional capacity assessed by walking test and respiratory and lower limb muscle function in community-dwelling elders

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Leonardo A. Simões

2010-02-01

Full Text Available CONTEXTUALIZAÇÃO: A sarcopenia é considerada o fator mais significativo na redução da força muscular periférica e respiratória e pode ocasionar incapacidades progressivas, perda de independência e interferir na capacidade funcional dos idosos. OBJETIVOS: Caracterizar a força dos músculos respiratórios (pressão inspiratória máxima - PImax e pressão expiratória máxima - PEmax e de membros inferiores (MMII, bem como as possíveis correlações existentes com a capacidade funcional dos idosos. MÉTODOS: Sessenta e cinco idosos, com 71,7±4,9 anos; foram avaliados por dinamometria isocinética para flexores e extensores dos joelhos, manovacuometria analógica para os músculos respiratórios pelo teste de caminhada de 6 minutos para capacidade funcional. Foram utilizados os testes Mann-Whitney e t de Student para comparação entre os gêneros. As correlações foram calculadas pelo coeficiente de correlação de Pearson. Para todos os testes foi considerado pBACKGROUND: Sarcopenia is the most significant factor in the decline of peripheral and respiratory muscle strength. It can lead to progressive disability, loss of independence and impaired functional capacity. OBJECTIVES: To determine the strength of respiratory muscles (maximal inspiratory pressure - MIP and maximal expiratory pressure - MEP and lower limb muscles, and to explore the possible relationships between these variables and the functional capacity of the elderly. METHODS: Sixty-five elderly patients (71.7±4.9 years old took part in the study. Isokinetic dynamometry was used to assess the knee flexors and extensors, an analog vacuum manometer was used to assess the respiratory muscles, and the six-minute walking test was used as an outcome of functional capacity. The Mann-Whitney test and Student's t-test were used for gender comparison. The relationships were investigated using Pearson's correlation. The significance level was p<0.05. RESULTS: The lower limb and

The relationship between exercise-induced muscle fatigue, arterial blood flow and muscle perfusion after 56 days local muscle unloading.

Science.gov (United States)

Weber, Tobias; Ducos, Michel; Mulder, Edwin; Beijer, Åsa; Herrera, Frankyn; Zange, Jochen; Degens, Hans; Bloch, Wilhelm; Rittweger, Jörn

2014-05-01

In the light of the dynamic nature of habitual plantar flexor activity, we utilized an incremental isokinetic exercise test (IIET) to assess the work-related power deficit (WoRPD) as a measure for exercise-induced muscle fatigue before and after prolonged calf muscle unloading and in relation to arterial blood flow and muscle perfusion. Eleven male subjects (31 ± 6 years) wore the HEPHAISTOS unloading orthosis unilaterally for 56 days. It allows habitual ambulation while greatly reducing plantar flexor activity and torque production. Endpoint measurements encompassed arterial blood flow, measured in the femoral artery using Doppler ultrasound, oxygenation of the soleus muscle assessed by near-infrared spectroscopy, lactate concentrations determined in capillary blood and muscle activity using soleus muscle surface electromyography. Furthermore, soleus muscle biopsies were taken to investigate morphological muscle changes. After the intervention, maximal isokinetic torque was reduced by 23·4 ± 8·2% (Pflow, tissue oxygenation, lactate concentrations and EMG median frequency kinematics during the exercise test were comparable before and after the intervention, whereas the increase of RMS in response to IIET was less following the intervention (P = 0·03). In conclusion, following submaximal isokinetic muscle work exercise-induced muscle fatigue is unaffected after prolonged local muscle unloading. The observation that arterial blood flow was maintained may underlie the unchanged fatigability. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Visual aided pacing in respiratory maneuvers

Energy Technology Data Exchange (ETDEWEB)

Rambaudi, L R [Laboratorio de Biofisica y Fisiologia ' Antonio Sadi Frumento' (Argentina); Rossi, E [Catedra de Bioingenieria II (Argentina); Mantaras, M C [Catedra de Bioingenieria II (Argentina); Perrone, M S [Laboratorio de Biofisica y Fisiologia ' Antonio Sadi Frumento' (Argentina); Siri, L Nicola [Catedra de Bioingenieria II (Argentina)

2007-11-15

A visual aid to pace self-controlled respiratory cycles in humans is presented. Respiratory manoeuvres need to be accomplished in several clinic and research procedures, among others, the studies on Heart Rate Variability. Free running respiration turns to be difficult to correlate with other physiologic variables. Because of this fact, voluntary self-control is asked from the individuals under study. Currently, an acoustic metronome is used to pace respiratory frequency, its main limitation being the impossibility to induce predetermined timing in the stages within the respiratory cycle. In the present work, visual driven self-control was provided, with separate timing for the four stages of a normal respiratory cycle. This visual metronome (ViMet) was based on a microcontroller which power-ON and -OFF an eight-LED bar, in a four-stage respiratory cycle time series handset by the operator. The precise timing is also exhibited on an alphanumeric display.

Visual aided pacing in respiratory maneuvers

International Nuclear Information System (INIS)

Rambaudi, L R; Rossi, E; Mantaras, M C; Perrone, M S; Siri, L Nicola

2007-01-01

A visual aid to pace self-controlled respiratory cycles in humans is presented. Respiratory manoeuvres need to be accomplished in several clinic and research procedures, among others, the studies on Heart Rate Variability. Free running respiration turns to be difficult to correlate with other physiologic variables. Because of this fact, voluntary self-control is asked from the individuals under study. Currently, an acoustic metronome is used to pace respiratory frequency, its main limitation being the impossibility to induce predetermined timing in the stages within the respiratory cycle. In the present work, visual driven self-control was provided, with separate timing for the four stages of a normal respiratory cycle. This visual metronome (ViMet) was based on a microcontroller which power-ON and -OFF an eight-LED bar, in a four-stage respiratory cycle time series handset by the operator. The precise timing is also exhibited on an alphanumeric display

Expiratory muscle control during vomiting - Role of brain stem expiratory neurons

Science.gov (United States)

Miller, A. D.; Tan, L. K.

1987-01-01

The neural mechanisms controlling the muscles involved during vomiting were examined using decerebrated cats. In one experiment, the activity of the ventral respiratory group (VRG) expiratory (E) neurons was recorded during induced 'fictive vomiting' (i.e., a series of bursts of coactivation of abdominal and phrenic nerves that would be expected to produce expulsion in unparalyzed animals) and vomiting. In a second, abdominal muscle electromyographic and nerve activity were compared before and after sectioning the axons of descending VRG E neurons as they cross the midline between C1 and the obex (the procedure that is known to abolish expiratory modulation of internal intercostal muscle activity). The results of the study indicate that the abdominal muscles are controlled differently during respiration and vomiting.

[Great depth pneumatic caisson and its load work involved with the efficiency of respiratory protection].

Science.gov (United States)

Shibayama, M; Oda, S; Takeuchi, J; Ikeda, Y; Yamamura, I; Mano, Y

1989-07-01

Pneumatic caisson work in Japan has been in operation since 1924. Afterward, this technique of compressed air work has been utilized in the constructions like as foundation works, the basements, and shafts of the bottom tunnel or shields for subway and so forth. While, it means for people to be exposed to hyperbaric environment that they use compressed air work, this technique has risks to be suffered from not only decompression sickness (DCS) but toxicity of poisonous gas or oxygen deficiency. However, this technique is necessary for urban civil engineering and recent compressed air works over than 1.0 kg/cm2 has been increased in 1.5 times more than in 1970's and the higher compressed air work more than 4.0 kg/cm2 will be actually planned in near future. So unmanned caisson work is considered as a better technique for such high pressure work, even though people must enter into hyperbaric working fields for maintenance or repair of unmanned operated machinery and materials. This research is to establish the safety work under hyperbaric environment within 7 kg/cm2. It is necessary for us to establish the system not only to keep safety but to maintain working efficiency. According to obtain the purpose, the effect of respiratory protection has been investigated and work load under hyperbaric caisson work has also been studied.

Respiratory Responses to Stimulation of Branchial Vagus Nerve Ganglia of a Teleost Fish

NARCIS (Netherlands)

Ballintijn, C.M.; Luiten, P.G.M.

1983-01-01

The effects of electrical stimulation of epibranchial vagus ganglia upon respiration of the carp were investigated. Single shocks evoked fast twitch responses in a number of respiratory muscles with latencies around 18 msec to the beginning and 30-35 msec to the peak of activity. Shocks given during

Muscle contraction duration and fibre recruitment influence blood flow and oxygen consumption independent of contractile work during steady-state exercise in humans.

Science.gov (United States)

Richards, Jennifer C; Crecelius, Anne R; Kirby, Brett S; Larson, Dennis G; Dinenno, Frank A

2012-06-01

We tested the hypothesis that, among conditions of matched contractile work, shorter contraction durations and greater muscle fibre recruitment result in augmented skeletal muscle blood flow and oxygen consumption ( ) during steady-state exercise in humans. To do so, we measured forearm blood flow (FBF; Doppler ultrasound) during 4 min of rhythmic hand-grip exercise in 24 healthy young adults and calculated forearm oxygen consumption ( ) via blood samples obtained from a catheter placed in retrograde fashion into a deep vein draining the forearm muscle. In protocol 1 (n = 11), subjects performed rhythmic isometric hand-grip exercise at mild and moderate intensities during conditions in which time-tension index (isometric analogue of work) was held constant but contraction duration was manipulated. In this protocol, shorter contraction durations led to greater FBF (184 ± 25 versus 164 ± 25 ml min(-1)) and (23 ± 3 versus 17 ± 2 ml min(-1); both P flow. Our collective data indicate that, among matched workloads, shorter contraction duration and greater muscle fibre recruitment augment FBF and during mild-intensity forearm exercise, and that muscle blood flow is more closely related to metabolic cost ( ) rather than contractile work per se during steady-state exercise in humans.

Força muscular respiratória e capacidade funcional em idosas hipertensas com sonolência diurna excessiva Respiratory muscle strength and physical fitness in hypertensive elderly women with excessive daytime sleepiness

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Rafaela Pedrosa

2010-06-01

Full Text Available O objetivo do estudo foi verificar se a sonolência diurna excessiva (SDE afeta a capacidade funcional (CF e força muscular respiratória entre idosas hipertensas. O estudo avaliou 32 idosas hipertensas, divididas em dois grupos (com SDE, n=17, 64,9±5,3 anos; e sem SDE, n=15, 65,9±5,5 anos, quanto a: força muscular respiratória, por manovacuometria; CF, pelo Questionário para avaliação de limitação das atividades e por testes de aptidão funcional; nível de atividade física, pelo questionário internacional de atividade física IPAQ; grau de SDE, pela escala de sonolência de Epworth; qualidade do sono, pelo índice de qualidade do sono de Pittsburgh; e intensidade do ronco, pela escala de ronco de Stanford. Os dois grupos, homogêneos quanto a características antropométricas e da hipertensão, foram comparados estatisticamente quanto a parâmetros de sono, pressões respiratórias máximas, nível de atividade física e CF. Foi encontrada diferença significativa na qualidade do sono (p=0,03, tendo as hipertensas com SDE qualidade de sono muito ruim; porém não foram encontradas diferenças significativas entre os grupos nas pressões inspiratória e expiratória máximas, nem quanto aos testes de CF. Conclui-se que a força dos músculos respiratórios não sofre alteração em decorrência da presença de SDE em idosas hipertensas e que essa sonolência não interfere na capacidade funcional.The purpose of the study was to inquire whether excessive daytime sleepiness (EDS affects functional capacity (FC and respiratory muscle strength in elderly hypertensive patients. Thirty-two elderly hypertensive female patients were divided into two groups (with EDS, n=17, mean age 64.9±5.3; without EDS, n=15, mean age 65.9±5.5 and were assessed as to respiratory muscle strength by spirometry; FC, by the Questionnaire on limitations in physical activities and by functional fitness tests; physical activity level, by the International

Determinants of Chronic Respiratory Symptoms among Pharmaceutical Factory Workers

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Sahle Asfaw

2018-01-01

Full Text Available Background. Chronic respiratory symptoms including chronic cough, chronic phlegm, wheezing, shortness of breath, and chest pain are manifestations of respiratory problems which are mainly evolved as a result of occupational exposures. This study aims to assess determinants of chronic respiratory symptoms among pharmaceutical factory workers. Methods. A case control study was carried out among 453 pharmaceutical factory workers with 151 cases and 302 controls. Data was collected using pretested and structured questionnaire. The data was analyzed using descriptive statistics and bivariate and multivariate analysis. Result. Previous history of chronic respiratory diseases (AOR = 3.36, 95% CI = 1.85–6.12, family history of chronic respiratory diseases (AOR = 2.55, 95% CI = 1.51–4.32, previous dusty working environment (AOR = 2.26, 95% CI = 1.07–4.78, ever smoking (AOR = 3.66, 95% CI = 1.05–12.72, and service years (AOR = 1.86, 95% CI = 1.16–2.99 showed statistically significant association with chronic respiratory symptoms. Conclusion. Previous history of respiratory diseases, family history of chronic respiratory diseases, previous dusty working environment, smoking, and service years were determinants of chronic respiratory symptoms. Public health endeavors to prevent the burden of chronic respiratory symptoms among pharmaceutical factory workers should target the reduction of adverse workplace exposures and discouragement of smoking.

[The changes of physiological reactivity of cardiorespiratory system to respiratory homeostasis with the use of complex stimulation of special work capacity].

Science.gov (United States)

Lysenko, O M

2012-01-01

We present the influence of the program of special additional stimulation of work capacity of high-performance athletes on the sensitivity of cardiorespiratory system to hypercapnic and hypoxic shifts in respiratory homeostasis. We found that under the influence of the pre-start complex a decrease in the sensitivity of ventilator responses to CO2-H+ stimuli in combination with a reduction in the thresholds of the reaction take place. This creates conditions for increased mobilization properties of the cardiorespiratory system and economization of its reaction under conditions of changes of respiratory homeostasis characteristic of intense training and competitive loads in the sport.

Does caffeine alter muscle carbohydrate and fat metabolism during exercise?

DEFF Research Database (Denmark)

Graham, Terry E; Battram, Danielle S; Dela, Flemming

2008-01-01

and carbohydrate metabolism. While caffeine certainly mobilizes fatty acids from adipose tissue, rarely have measures of the respiratory exchange ratio indicated an increase in fat oxidation. However, this is a difficult measure to perform accurately during exercise, and small changes could be physiologically...... important. The few studies examining human muscle metabolism directly have also supported the fact that there is no change in fat or carbohydrate metabolism, but these usually have had a small sample size. We combined the data from muscle biopsy analyses of several similar studies to generate a sample size...

The influence of a fentanyl and dexmedetomidine combination on external respiratory functions in acute hemorrhage model

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Nikolay G. Vengerovich

2017-01-01

Full Text Available Background. The synthetic opioid analgesic fentanyl is widely used for prophylaxis and therapy of traumatic shock associated with massive bleeding. Its side effects – skeletal muscle rigidity and respiratory center depression – are especially pronounced with repeated administration. It is rational to apply fentanyl in diminished doses in combination with non-opioid analgesics in order to reduce respiratory disturbances risk.Aim. The aim of the work is to justify the influence of opioid analgesic fentanyl and α2 -adrenomimetic dexmedetomidine combination on external respiratory functions in acute hemorrhage model.Materials and methods. Acute loss of 35–40% of circulating blood volume was modeled in experiments on 75 white mongrel male rats. The external respiratory functions (respiratory rate, respiratory volume, breath volume per minute were estimated in animals of 5 groups: 1 – rats without analgesic help (controls; 2–3 – rats receiving a single fentanyl intramuscular injection (ED99 98,96 mcg/kg or fentanyl together with dexme detomidine (ED99 of combination 67,94 mcg/kg 15 min after acute blood loss; 4–5 – rats receiving the same drugs 15 min, 30, 45 and 60 min later.Results. In experimental acute loss of 35–40% of circulating blood volume, 15 min later a secondary acute respiratory failure developed with a drop of respiratory rate, respiratory volume and volume of breath per minute by 30%, 21 and 47% (p < 0,05. The external respiratory functions recoverеd after 4 h mainly due to the increase of respiratory volume. A single intramuscular injection of fentanyl caused respiratory depression 15 min after experimental blood loss which resulted in the decrease of breath volume per minute to 30–61% (p < 0,05 for 90 min. Four intramuscular injections of fentanyl 15 min, 30, 45 and 60 min after hemorrhage caused a severe respiratory dysfunction, accompanied by apnea periods and Biot’s respiration. Respiratory rate was reduced

Actovegin, a non-prohibited drug increases oxidative capacity in human skeletal muscle

DEFF Research Database (Denmark)

Søndergård, Stine D; Dela, Flemming; Helge, Jørn W

2016-01-01

Actovegin, a deproteinized haemodialysate of calf blood, is suggested to have ergogenic properties, but this potential effect has never been investigated in human skeletal muscle. To investigate this purported ergogenic effect, we measured the mitochondrial respiratory capacity in permeabilized h...

Prospective exploratory muscle biopsy, imaging, and functional assessment in patients with late-onset Pompe disease treated with alglucosidase alfa: The EMBASSY Study

NARCIS (Netherlands)

A.T. van der Ploeg (Ans); Carlier, P.G. (Pierre G.); Carlier, R.-Y. (Robert-Yves); Kissel, J.T. (John T.); B. Schoser; Wenninger, S. (Stephan); Pestronk, A. (Alan); Barohn, R.J. (Richard J.); Dimachkie, M.M. (Mazen M.); Goker-Alpan, O. (Ozlem); Mozaffar, T. (Tahseen); Pena, L.D.M. (Loren D.M.); Simmons, Z. (Zachary); V. Straub; Guglieri, M. (Michela); Young, P. (Peter); Boentert, M. (Matthias); Baudin, P.-Y. (Pierre-Yves); S.C.A. Wens (Stephan); Shafi, R. (Raheel); Bjartmar, C. (Carl); B. Thurberg

2016-01-01

textabstractBackground Late-onset Pompe disease is characterized by progressive skeletal myopathy followed by respiratory muscle weakness, typically leading to loss of ambulation and respiratory failure. In this population, enzyme replacement therapy (ERT) with alglucosidase alfa has been shown to

Effects of inspiratory muscle exercise in the pulmonary function, autonomic modulation, and hemodynamic variables in older women with metabolic syndrome

Science.gov (United States)

Feriani, Daniele Jardim; Coelho, Hélio José; Scapini, Kátia Bilhar; de Moraes, Oscar Albuquerque; Mostarda, Cristiano; Ruberti, Olivia Moraes; Uchida, Marco Carlos; Caperuto, Érico Chagas; Irigoyen, Maria Cláudia; Rodrigues, Bruno

2017-01-01

The aim of the present study was to investigate the effects of inspiratory muscle exercise (IME) on metabolic and hemodynamic parameters, cardiac autonomic modulation and respiratory function of older women with metabolic syndrome (MS). For this, sixteen older women with MS and 12 aged-matched controls participated of the present study. Two days before and 2 days after the main experiment, fasting blood samples (i.e., total cholesterol, triglycerides and blood glucose), cardiac autonomic modulation (i.e., heart rate variability), and respiratory muscle function were obtained and evaluated. The sessions of physical exercise was based on a IME, which was performed during 7 days. Each session of IME was performed during 20 min, at 30% of maximal static inspiratory pressure. In the results, MS group presented higher levels of triglycerides, blood glucose, and systolic blood pressure when compared to control group. IME was not able to change these variables. However, although MS group showed impaired respiratory muscle strength and function, as well as cardiac autonomic modulation, IME was able to improve these parameters. Thus, the data showed that seven days of IME are capable to improve respiratory function and cardiac autonomic modulation of older women with MS. These results indicate that IME can be a profitable therapy to counteracting the clinical markers of MS, once repeated sessions of acute IME can cause chronical alterations on respiratory function and cardiac autonomic modulation. PMID:28503537

Healthy Muscles Matter

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... or lying down, and faster when you’re running or playing sports and your skeletal muscles need more blood to help them do their work. What can go wrong? Injuries Almost everyone has had sore muscles after exercising ...

The influence of flow redistribution on working rat muscle oxygenation.

NARCIS (Netherlands)

Hoofd, L.J.C.; Degens, H.

2009-01-01

We applied a theoretical model of muscle tissue O2 transport to investigate the effects of flow redistribution on rat soleus muscle oxygenation. The situation chosen was the anaerobic threshold where redistribution of flow is expected to have the largest impact. In the basic situation all

Perceived Competence and Comfort in Respiratory Protection

Science.gov (United States)

Burgel, Barbara J.; Novak, Debra; Burns, Candace M.; Byrd, Annette; Carpenter, Holly; Gruden, MaryAnn; Lachat, Ann; Taormina, Deborah

2015-01-01

In response to the Institute of Medicine (2011) report Occupational Health Nurses and Respiratory Protection: Improving Education and Training, a nationwide survey was conducted in May 2012 to assess occupational health nurses’ educational preparation, roles, responsibilities, and training needs in respiratory protection. More than 2,000 occupational health nurses responded; 83% perceived themselves as competent, proficient, or expert in respiratory protection, reporting moderate comfort with 12 respiratory program elements. If occupational health nurses had primary responsibility for the respiratory protection program, they were more likely to perceive higher competence and more comfort in respiratory protection, after controlling for occupational health nursing experience, highest education, occupational health nursing certification, industry sector, Association of Occupational Health Professionals in Healthcare membership, taking a National Institute for Occupational Safety and Health spirometry course in the prior 5 years, and perceiving a positive safety culture at work. These survey results document high perceived competence and comfort in respiratory protection. These findings support the development of targeted educational programs and interprofessional competencies for respiratory protection. PMID:23429638

Mask-wearing and respiratory infection in healthcare workers in Beijing, China

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Peng Yang

Full Text Available OBJECTIVES: The aim of the study was to determine rates of mask-wearing, of respiratory infection and the factors associated with mask-wearing and of respiratory infection in healthcare workers (HCWs in Beijing during the winter of 2007/2008. METHODS: We conducted a survey of 400 HCWs working in eight hospitals in Beijing by face to face interview using a standardized questionnaire. RESULTS: We found that 280/400 (70.0% of HCWs were compliant with mask-wearing while in contact with patients. Respiratory infection occurred in 238/400 (59.5% subjects from November, 2007 through February, 2008. Respiratory infection was higher among females (odds ratio [OR], 2.00 [95% confidence interval {CI}, 1.16-3.49] and staff working in larger hospitals (OR, 1.72 [95% CI, 1.092.72], but was lower among subjects with seasonal influenza vaccination (OR, 0.46 [95% CI, 0.280.76], wearing medical masks (reference: cotton-yarn; OR, 0.60 [95% CI, 0.39-0.91] or with good mask-wearing adherence (OR, 0.60 [95% CI, 0.37-0.98]. The risk of respiratory infection of HCWs working in low risk areas was similar to that of HCWs in high risk area. CONCLUSION: Our data suggest that female HCWs and staffs working in larger hospitals are the focus of prevention and control of respiratory infection in Beijing hospitals. Mask-wearing and seasonal influenza vaccination are protective for respiratory infection in HCWs; the protective efficacy of medical masks is better than that of cotton yarn ones; respiratory infection of HCWs working in low risk areas should also be given attention.

Life-threatening hypokalemia following rapid correction of respiratory acidosis.

Science.gov (United States)

Hammond, Kendra; You, David; Collins, Eileen G; Leehey, David J; Laghi, Franco

2013-01-01

A 56-year-old woman with a history of paraplegia and chronic pain due to neuromyelitis optica (Devic's syndrome) was admitted to a spinal cord injury unit for management of a sacral decubitus ulcer. During the hospitalization, she required emergency transfer to the intensive care unit (ICU) because of progressive deterioration of respiratory muscle function, severe respiratory acidosis, obtundation and hypotension. Upon transfer to the ICU, arterial blood gas revealed severe acute-on-chronic respiratory acidosis (pH 7.00, PCO2 120 mm Hg, PO2 211 mm Hg). The patient was immediately intubated and mechanically ventilated. Intravenous fluid boluses of normal saline (10.5 L in about 24 h) and vasopressors were started with rapid correction of hypotension. In addition, she was given hydrocortisone. Within 40 min of initiation of mechanical ventilation, there was improvement in acute respiratory acidosis. Sixteen hours later, however, the patient developed life-threatening hypokalemia (K(+) of 2.1 mEq/L) and hypomagnesemia (Mg of 1.4 mg/dL). Despite aggressive potassium supplementation, hypokalemia continued to worsen over the next several hours (K(+) of 1.7 mEq/L). Urine studies revealed renal potassium wasting. We reason that the recalcitrant life-threatening hypokalemia was caused by several mechanisms including total body potassium depletion (chronic respiratory acidosis), a shift of potassium from the extracellular to intracellular space (rapid correction of respiratory acidosis with mechanical ventilation), increased sodium delivery to the distal nephron (normal saline resuscitation), hyperaldosteronism (secondary to hypotension plus administration of hydrocortisone) and hypomagnesemia. We conclude that rapid correction of respiratory acidosis, especially in the setting of hypotension, can lead to life-threatening hypokalemia. Serum potassium levels must be monitored closely in these patients, as failure to do so can lead to potentially lethal consequences

Intermittent hypoxia, respiratory plasticity and sleep apnea in humans: present knowledge and future investigations.

Science.gov (United States)

Mateika, Jason H; Syed, Ziauddin

2013-09-15

This review examines the role that respiratory plasticity has in the maintenance of breathing stability during sleep in individuals with sleep apnea. The initial portion of the review considers the manner in which repetitive breathing events may be initiated in individuals with sleep apnea. Thereafter, the role that two forms of respiratory plasticity, progressive augmentation of the hypoxic ventilatory response and long-term facilitation of upper airway and respiratory muscle activity, might have in modifying breathing events in humans is examined. In this context, present knowledge regarding the initiation of respiratory plasticity in humans during wakefulness and sleep is addressed. Also, published findings which reveal that exposure to intermittent hypoxia promotes breathing instability, at least in part, because of progressive augmentation of the hypoxic ventilatory response and the absence of long-term facilitation, are considered. Next, future directions are presented and are focused on the manner in which forms of plasticity that stabilize breathing might be promoted while diminishing destabilizing forms, concurrently. These future directions will consider the potential role of circadian rhythms in the promotion of respiratory plasticity and the role of respiratory plasticity in enhancing established treatments for sleep apnea. Published by Elsevier B.V.

Intermittent hypoxia, respiratory plasticity and sleep apnea in humans; present knowledge and future investigations

Science.gov (United States)

Mateika, Jason H.; Syed, Ziauddin

2013-01-01

This review examines the role that respiratory plasticity has in the maintenance of breathing stability during sleep in individuals with sleep apnea. The initial portion of the review considers the manner in which repetitive breathing events may be initiated in individuals with sleep apnea. Thereafter, the role that two forms of respiratory plasticity, progressive augmentation of the hypoxic ventilatory response and long-term facilitation of upper airway and respiratory muscle activity, might have in modifying breathing events in humans is examined. In this context, present knowledge regarding the initiation of respiratory plasticity in humans during wakefulness and sleep is addressed. Also, published findings which reveal that exposure to intermittent hypoxia promotes breathing instability, at least in part, because of progressive augmentation of the hypoxic ventilatory response and the absence of long-term facilitation, are considered. Next, future directions are presented and are focused on the manner in which forms of plasticity that stabilize breathing might be promoted while diminishing destabilizing forms, concurrently. These future directions will consider the potential role of circadian rhythms in the promotion of respiratory plasticity and the role of respiratory plasticity in enhancing established treatments for sleep apnea. PMID:23587570

Modification of working conditions based on ergo THK reducing workload, muscle tension, and fatigue of rice milling workers in J village

Science.gov (United States)

Ruliati, L. P.; Adiputra, N.; Sutjana, I. D. P.; Sutajaya, I. M.

2017-11-01

Rice mill is one of the businesses in informal sector. From the rice milling process, ergonomic problems arise when employees work with bent position that done repeatedly to lift grain sacks to be transferred to peeler machine. This situation will affect the comfort of work, thus increasing the workload, muscle tension, and fatigue. The consequence will certainly affect the health and productivity of workers. In this study introduces ergo Tri Hita Karana (ergo THK) as an ergonomics intervention model which solves ergonomics problems of the cultural aspects of THK. The study aim is to determine the modification of working conditions based Ergo THK to reduce workload, muscle tension and fatigue. This research uses Randomized Pretest and Posttest Control Group Design experimental design. The subjects were 30 male rice mill workers with an age range of 16 until 56 years, and then divided into 15 subjects in the control group and 15 subjects in the treatment group. The results showed that the average posttest workloads in the control group are 136.950 more less 0.297 and in the treatment group are 107.60 more less 0.396. Significance analysis showed that after the two groups done their activities, the average workload significantly different p less than 0.005. The amount of reduction in the workload between the two groups was 21.43 percent. In muscle tension posttest showed that the mean score of the muscle tension in the control group was 62.67 more less 7.31 and the treatment group was 20.96 more less 2.96. Significance analysis showed that both groups mean muscle-tension results were significantly different p less than 0.005. The amount of reduction in tension between the control group and the treatment group while working was 66.55 percent. At fatigue posttest showed that the mean score of fatigue in the control group was 76.40 more less 13.51 and the treatment group was 55.53 more less 9.51. Significant analysis showed that the mean fatigue of both groups

Computerized Respiratory Sounds: Novel Outcomes for Pulmonary Rehabilitation in COPD.

Science.gov (United States)

Jácome, Cristina; Marques, Alda

2017-02-01

Computerized respiratory sounds are a simple and noninvasive measure to assess lung function. Nevertheless, their potential to detect changes after pulmonary rehabilitation (PR) is unknown and needs clarification if respiratory acoustics are to be used in clinical practice. Thus, this study investigated the short- and mid-term effects of PR on computerized respiratory sounds in subjects with COPD. Forty-one subjects with COPD completed a 12-week PR program and a 3-month follow-up. Secondary outcome measures included dyspnea, self-reported sputum, FEV 1 , exercise tolerance, self-reported physical activity, health-related quality of life, and peripheral muscle strength. Computerized respiratory sounds, the primary outcomes, were recorded at right/left posterior chest using 2 stethoscopes. Air flow was recorded with a pneumotachograph. Normal respiratory sounds, crackles, and wheezes were analyzed with validated algorithms. There was a significant effect over time in all secondary outcomes, with the exception of FEV 1 and of the impact domain of the St George Respiratory Questionnaire. Inspiratory and expiratory median frequencies of normal respiratory sounds in the 100-300 Hz band were significantly lower immediately (-2.3 Hz [95% CI -4 to -0.7] and -1.9 Hz [95% CI -3.3 to -0.5]) and at 3 months (-2.1 Hz [95% CI -3.6 to -0.7] and -2 Hz [95% CI -3.6 to -0.5]) post-PR. The mean number of expiratory crackles (-0.8, 95% CI -1.3 to -0.3) and inspiratory wheeze occupation rate (median 5.9 vs 0) were significantly lower immediately post-PR. Computerized respiratory sounds were sensitive to short- and mid-term effects of PR in subjects with COPD. These findings are encouraging for the clinical use of respiratory acoustics. Future research is needed to strengthen these findings and explore the potential of computerized respiratory sounds to assess the effectiveness of other clinical interventions in COPD. Copyright © 2017 by Daedalus Enterprises.

Respiratory Diseases in Children: studies in general practice

NARCIS (Netherlands)

J.H.J.M. Uijen (Hans)

2011-01-01

textabstractThe work presented in this thesis covers various aspects of the epidemiology, diagnosis and management of various respiratory symptoms and diseases in children frequently encountered in general practice. These respiratory tract symptoms and diseases can be categorized into symptoms and

Short-term respiratory effects of cleaning exposures in female domestic cleaners.

Science.gov (United States)

Medina-Ramón, M; Zock, J P; Kogevinas, M; Sunyer, J; Basagaña, X; Schwartz, J; Burge, P S; Moore, V; Antó, J M

2006-06-01

Symptoms of obstructive lung disease in domestic cleaners have been related to the use of bleach and other irritant cleaning products. The short-term effects of cleaning exposures on respiratory symptoms and peak expiratory flow (PEF) were investigated in domestic cleaners with respiratory disorders. In a panel study, 43 female domestic cleaners with a recent history of asthma and/or chronic bronchitis completed a 2-week diary, collecting information on respiratory symptoms, PEF and cleaning exposures. Mixed regression models were used to assess daily changes in symptoms and PEF associated with specific cleaning exposures. The probability of having work-related asthma was individually assessed by a computerised diagnostic system and an occupational asthma expert. Lower respiratory tract symptoms were more common on working days and were predominantly associated with exposure to diluted bleach, degreasing sprays/atomisers and air fresheners. Associations with upper respiratory tract symptoms and PEF were less apparent. Eleven (30%) subjects scored positively for work-related asthma. It is concluded that exposure to certain irritant cleaning products aggravates lower respiratory tract symptoms in female domestic cleaners with asthma or chronic bronchitis.

Oral Gingival Cell Cigarette Smoke Exposure Induces Muscle Cell Metabolic Disruption

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Andrea C. Baeder

2016-01-01

Full Text Available Cigarette smoke exposure compromises health through damaging multiple physiological systems, including disrupting metabolic function. The purpose of this study was to determine the role of oral gingiva in mediating the deleterious metabolic effects of cigarette smoke exposure on skeletal muscle metabolic function. Using an in vitro conditioned medium cell model, skeletal muscle cells were incubated with medium from gingival cells treated with normal medium or medium containing suspended cigarette smoke extract (CSE. Following incubation of muscle cells with gingival cell conditioned medium, muscle cell mitochondrial respiration and insulin signaling and action were determined as an indication of overall muscle metabolic health. Skeletal muscle cells incubated with conditioned medium of CSE-treated gingival cells had a profound reduction in mitochondrial respiration and respiratory control. Furthermore, skeletal muscle cells had a greatly reduced response in insulin-stimulated Akt phosphorylation and glycogen synthesis. Altogether, these results provide a novel perspective on the mechanism whereby cigarette smoke affects systemic metabolic function. In conclusion, we found that oral gingival cells treated with CSE create an altered milieu that is sufficient to both disrupted skeletal muscle cell mitochondrial function and insulin sensitivity.

Active pauses induce more variable electromyographic pattern of the trapezius muscle activity during computer work

DEFF Research Database (Denmark)

Samani, Afshin; Holtermann, Andreas; Søgaard, Karen

2009-01-01

, with passive (relax) and active (30% maximum voluntary contraction of shoulder elevation) pauses given every 2 min at two different work paces (low/high). Bipolar SEMG from four parts of the trapezius muscle was recorded. The relative rest time was higher for the lower parts compared with the upper......The aim of this laboratory study was to evaluate effects of active and passive pauses and investigate the distribution of the trapezius surface electromyographic (SEMG) activity during computer mouse work. Twelve healthy male subjects performed four sessions of computer work for 10 min in one day...... of the trapezius (pwork with active pause compared with passive one (p

Influence of mental workload on muscle endurance, fatigue, and recovery during intermittent static work.

Science.gov (United States)

Mehta, Ranjana K; Agnew, Michael J

2012-08-01

Most occupational tasks involve some level of mental/cognitive processing in addition to physical work; however, the etiology of work-related musculoskeletal disorders (WMSDs) due to these demands remains unclear. The aim of this study was to quantify the interactive effects of physical and mental workload on muscle endurance, fatigue, and recovery during intermittent work. Twelve participants, balanced by gender, performed intermittent static shoulder abductions to exhaustion at 15, 35, and 55% of individual maximal voluntary contraction (MVC), in the absence (control) and presence (concurrent) of a mental arithmetic task. Changes in muscular capacity were determined using endurance time, strength decline, electromyographic (EMG) fatigue indicators, muscle oxygenation, and heart rate measures. Muscular recovery was quantified through changes in strength and physiological responses. Mental workload was associated with shorter endurance times, specifically at 35% MVC, and greater strength decline. EMG and oxygenation measures showed similar changes during fatigue manifestation during concurrent conditions compared to the control, despite shorter endurance times. Moreover, decreased heart rate variability during concurrent demand conditions indicated increased mental stress. Although strength recovery was not influenced by mental workload, a slower heart rate recovery was observed after concurrent demand conditions. The findings from this study provide fundamental evidence that physical capacity (fatigability and recovery) is adversely affected by mental workload. Thus, it is critical to determine or evaluate occupational demands based on modified muscular capacity (due to mental workload) to reduce risk of WMSD development.

Early Life Exposure to Chronic Intermittent Hypoxia Primes Increased Susceptibility to Hypoxia-Induced Weakness in Rat Sternohyoid Muscle During Adulthood

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Fiona B Mcdonald

2016-03-01

Full Text Available Intermittent hypoxia is a feature of apnea of prematurity, chronic lung disease and sleep apnea. Despite the clinical relevance, the long-term effects of hypoxic exposure in early life on respiratory control are not well defined. We recently reported that exposure to chronic intermittent hypoxia (CIH during postnatal development (pCIH causes upper airway muscle weakness in both sexes, which persists for several weeks. We sought to examine if there are persistent sex-dependent effects of pCIH on respiratory muscle function into adulthood and/or increased susceptibility to re-exposure to CIH in adulthood in animals previously exposed to CIH during postnatal development. We hypothesized that pCIH would cause long-lasting muscle impairment and increased susceptibility to subsequent hypoxia. Within 24 hours of delivery, pups and their respective dams were exposed to CIH: 90s of hypoxia reaching 5% O2 at nadir; once every 5 min, 8 hrs per day for 3 weeks. Sham groups were exposed to normoxia in parallel. Three groups were studied: sham; pCIH; and pCIH combined with adult CIH (p+aCIH, where a subset of the pCIH-exposed pups were re-exposed to the same CIH paradigm beginning at 13 weeks. Following gas exposures, sternohyoid and diaphragm muscle isometric contractile and endurance properties were examined ex vivo. There was no apparent lasting effect of pCIH on respiratory muscle function in adults. However, in both males and females, re-exposure to CIH in adulthood in pCIH-exposed animals caused sternohyoid (but not diaphragm weakness. Exposure to this paradigm of CIH in adulthood alone had no effect on muscle function. Persistent susceptibility in pCIH-exposed airway dilator muscle to subsequent hypoxic insult may have implications for the control of airway patency in adult humans exposed to intermittent hypoxic stress during early life.

Early life exposure to chronic intermittent Hypoxia Primes Increased Susceptibility to Hypoxia-Induced Weakness in Rat Sternohyoid Muscle during adulthood.

LENUS (Irish Health Repository)

McDonald, Fiona B

2016-03-01

Intermittent hypoxia is a feature of apnea of prematurity (AOP), chronic lung disease, and sleep apnea. Despite the clinical relevance, the long-term effects of hypoxic exposure in early life on respiratory control are not well defined. We recently reported that exposure to chronic intermittent hypoxia (CIH) during postnatal development (pCIH) causes upper airway muscle weakness in both sexes, which persists for several weeks. We sought to examine if there are persistent sex-dependent effects of pCIH on respiratory muscle function into adulthood and\\/or increased susceptibility to re-exposure to CIH in adulthood in animals previously exposed to CIH during postnatal development. We hypothesized that pCIH would cause long-lasting muscle impairment and increased susceptibility to subsequent hypoxia. Within 24 h of delivery, pups and their respective dams were exposed to CIH: 90 s of hypoxia reaching 5% O2 at nadir; once every 5 min, 8 h per day for 3 weeks. Sham groups were exposed to normoxia in parallel. Three groups were studied: sham; pCIH; and pCIH combined with adult CIH (p+aCIH), where a subset of the pCIH-exposed pups were re-exposed to the same CIH paradigm beginning at 13 weeks. Following gas exposures, sternohyoid and diaphragm muscle isometric contractile and endurance properties were examined ex vivo. There was no apparent lasting effect of pCIH on respiratory muscle function in adults. However, in both males and females, re-exposure to CIH in adulthood in pCIH-exposed animals caused sternohyoid (but not diaphragm) weakness. Exposure to this paradigm of CIH in adulthood alone had no effect on muscle function. Persistent susceptibility in pCIH-exposed airway dilator muscle to subsequent hypoxic insult may have implications for the control of airway patency in adult humans exposed to intermittent hypoxic stress during early life.

Shedding light on restoring respiratory function after spinal cord injury

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Warren J Alilain

2009-10-01

Full Text Available Loss of respiratory function is one of the leading causes of death following spinal cord injury. Because of this, much work has been done in studying ways to restore respiratory function following SCI - including pharmacological and regeneration strategies. With the emergence of new and powerful tools from molecular neuroscience, new therapeutically relevant alternatives to these approaches have become available, including expression of light sensitive proteins called channelrhodopsins. In this article we briefly review the history of various attempts to restore breathing after C2 hemisection, and focus on our recent work using the activation of light sensitive channels to restore respiratory function after experimental spinal cord injury. We also discuss how such light induced activity can help shed light on the inner workings of the central nervous system respiratory circuitry that controls diaphragmatic function.

The anti-malarial drug Mefloquine disrupts central autonomic and respiratory control in the working heart brainstem preparation of the rat

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Lall Varinder K

2012-12-01

Full Text Available Abstract Background Mefloquine is an anti-malarial drug that can have neurological side effects. This study examines how mefloquine (MF influences central nervous control of autonomic and respiratory systems using the arterially perfused working heart brainstem preparation (WHBP of the rat. Recordings of nerve activity were made from the thoracic sympathetic chain and phrenic nerve, while heart rate (HR and perfusion pressure were also monitored in the arterially perfused, decerebrate, rat WHBP. MF was added to the perfusate at 1 μM to examine its effects on baseline parameters as well as baroreceptor and chemoreceptor reflexes. Results MF caused a significant, atropine resistant, bradycardia and increased phrenic nerve discharge frequency. Chemoreceptor mediated sympathoexcitation (elicited by addition of 0.1 ml of 0.03% sodium cyanide to the aortic cannula was significantly attenuated by the application of MF to the perfusate. Furthermore MF significantly decreased rate of return to resting HR following chemoreceptor induced bradycardia. An increase in respiratory frequency and attenuated respiratory-related sympathetic nerve discharge during chemoreceptor stimulation was also elicited with MF compared to control. However, MF did not significantly alter baroreceptor reflex sensitivity. Conclusions These studies indicate that in the WHBP, MF causes profound alterations in autonomic and respiratory control. The possibility that these effects may be mediated through actions on connexin 36 containing gap junctions in central neurones controlling sympathetic nervous outflow is discussed.

Nanotechnology: Advancing the translational respiratory research

OpenAIRE

Dua, Kamal; Shukla, Shakti Dhar; de Jesus Andreoli Pinto, Terezinha; Hansbro, Philip Michael

2017-01-01

Considering the various limitations associated with the conventional dosage forms, nanotechnology is gaining increased attention in drug delivery particularly in respiratory medicine and research because of its advantages like targeting effects, improved pharmacotherapy, and patient compliance. This paper provides a quick snapshot about the recent trends and applications of nanotechnology to various translational and formulation scientists working on various respiratory diseases, which can he...

Measurements of respiratory illness among construction painters.

Science.gov (United States)

White, M C; Baker, E L

1988-08-01

The prevalence of different measurements of respiratory illness among construction painters was examined and the relation between respiratory illness and employment as a painter assessed in a cross sectional study of current male members of two local affiliates of a large international union of painters. Respiratory illness was measured by questionnaire and spirometry. Longer employment as a painter was associated with increased prevalence of chronic obstructive disease and an interactive effect was observed for smoking and duration of employment as a painter. Multiple regression analysis showed a significant association between years worked as a painter and a decrement in FEV1 equal to about 11 ml for each year worked. This association was larger among painters who had smoked. The prevalence of chronic bronchitis was significantly associated with increased use of spray application methods.

Role of PARP activity in lung cancer-induced cachexia: Effects on muscle oxidative stress, proteolysis, anabolic markers, and phenotype.

Science.gov (United States)

Chacon-Cabrera, Alba; Mateu-Jimenez, Mercè; Langohr, Klaus; Fermoselle, Clara; García-Arumí, Elena; Andreu, Antoni L; Yelamos, Jose; Barreiro, Esther

2017-12-01

Strategies to treat cachexia are still at its infancy. Enhanced muscle protein breakdown and ubiquitin-proteasome system are common features of cachexia associated with chronic conditions including lung cancer (LC). Poly(ADP-ribose) polymerases (PARP), which play a major role in chromatin structure regulation, also underlie maintenance of muscle metabolism and body composition. We hypothesized that protein catabolism, proteolytic markers, muscle fiber phenotype, and muscle anabolism may improve in respiratory and limb muscles of LC-cachectic Parp-1-deficient (Parp-1 -/- ) and Parp-2 -/- mice. In diaphragm and gastrocnemius of LC (LP07 adenocarcinoma) bearing mice (wild type, Parp-1 -/- , and Parp-2 -/- ), PARP activity (ADP-ribose polymers, pADPr), redox balance, muscle fiber phenotype, apoptotic nuclei, tyrosine release, protein ubiquitination, muscle-specific E3 ligases, NF-κB signaling pathway, markers of muscle anabolism (Akt, mTOR, p70S6K, and mitochondrial DNA) were evaluated along with body and muscle weights, and limb muscle force. Compared to wild type cachectic animals, in both respiratory and limb muscles of Parp-1 -/- and Parp-2 -/- cachectic mice: cancer induced-muscle wasting characterized by increased PARP activity, protein oxidation, tyrosine release, and ubiquitin-proteasome system (total protein ubiquitination, atrogin-1, and 20S proteasome C8 subunit) were blunted, the reduction in contractile myosin and atrophy of the fibers was attenuated, while no effects were seen in other structural features (inflammatory cells, internal or apoptotic nuclei), and markers of muscle anabolism partly improved. Activation of either PARP-1 or -2 is likely to play a role in muscle protein catabolism via oxidative stress, NF-κB signaling, and enhanced proteasomal degradation in cancer-induced cachexia. Therapeutic potential of PARP activity inhibition deserves attention. © 2017 Wiley Periodicals, Inc.

Evaluation of respiratory pattern during respiratory-gated radiotherapy

International Nuclear Information System (INIS)

Dobashi, Suguru; Mori, Shinichiro

2014-01-01

The respiratory cycle is not strictly regular, and generally varies in amplitude and period from one cycle to the next. We evaluated the characteristics of respiratory patterns acquired during respiratory gating treatment in more than 300 patients. A total 331 patients treated with respiratory-gated carbon-ion beam therapy were selected from a group of patients with thoracic and abdominal conditions. Respiratory data were acquired for a total of 3,171 fractions using an external respiratory sensing monitor and evaluated for respiratory cycle, duty cycle, magnitude of baseline drift, and intrafractional/interfractional peak inhalation/exhalation positional variation. Results for the treated anatomical sites and patient positioning were compared. Mean ± SD respiratory cycle averaged over all patients was 4.1 ± 1.3 s. Mean ± SD duty cycle averaged over all patients was 36.5 ± 7.3 %. Two types of baseline drift were seen, the first decremental and the second incremental. For respiratory peak variation, the mean intrafractional variation in peak-inhalation position relative to the amplitude in the first respiratory cycle (15.5 ± 9.3 %) was significantly larger than that in exhalation (7.5 ± 4.6 %). Interfractional variations in inhalation (17.2 ± 18.5 %) were also significantly greater than those in exhalation (9.4 ± 10.0 %). Statistically significant differences were observed between patients in the supine position and those in the prone position in mean respiratory cycle, duty cycle, and intra-/interfractional variations. We quantified the characteristics of the respiratory curve based on a large number of respiratory data obtained during treatment. These results might be useful in improving the accuracy of respiratory-gated treatment.

[Overactive muscles: it can be more serious than common myalgia or cramp].

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Molenaar, Joery P F; Snoeck, Marc M J; Voermans, Nicol C; van Engelen, Baziel G M

2016-01-01

Positive muscle phenomena are due to muscle overactivity. Examples are cramp, myalgia, and stiffness. These manifestations have mostly acquired causes, e.g. side-effects of medication, metabolic disorders, vitamin deficiency, excessive caffeine intake or neurogenic disorders. We report on three patients with various positive muscle phenomena, to illustrate the clinical signs that indicate an underlying myopathy. Patient A, a 56-year-old man, was diagnosed with muscle cramp in the context of excessive coffee use and previous lumbosacral radiculopathy. Patient B, a 71-year-old man, was shown to have RYR1-related myopathy. Patient C, a 42-year-old man, suffered from Brody myopathy. We propose for clinicians to look out for a number of 'red flags' that can point to an underlying myopathy, and call for referral to neurology if indicated. Red flags include second wind phenomenon, familial occurrence of similar complaints, marked muscle stiffness, myotonia, muscle weakness, muscle hypertrophy, and myoglobinuria. Establishing a correct diagnosis is important for proper treatment. Certain myopathies call for cardiac or respiratory screening.

The Pleiotropic Effect of Physical Exercise on Mitochondrial Dynamics in Aging Skeletal Muscle

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Elena Barbieri

2015-01-01

Full Text Available Decline in human muscle mass and strength (sarcopenia is one of the principal hallmarks of the aging process. Regular physical exercise and training programs are certain powerful stimuli to attenuate the physiological skeletal muscle alterations occurring during aging and contribute to promote health and well-being. Although the series of events that led to these muscle adaptations are poorly understood, the mechanisms that regulate these processes involve the “quality” of skeletal muscle mitochondria. Aerobic/endurance exercise helps to maintain and improve cardiovascular fitness and respiratory function, whereas strength/resistance-exercise programs increase muscle strength, power development, and function. Due to the different effect of both exercises in improving mitochondrial content and quality, in terms of biogenesis, dynamics, turnover, and genotype, combined physical activity programs should be individually prescribed to maximize the antiaging effects of exercise.

Maximal respiratory pressures and pulmonary function in male runners.

OpenAIRE

Cordain, L; Glisan, B J; Latin, R W; Tucker, A; Stager, J M

1987-01-01

To determine the effects of long term exercise on respiratory muscle strength, maximal inspiratory (Pl max) and expiratory (PE max) pressures, pulmonary volumes and capacities and anthropometric parameters were measured in a group of 101 male runners aged 16 to 58 years. The runners exhibited significantly (p less than 0.05) lower PE max (202 +/- 41 cm H2O and significantly greater residual lung volumes (RV) (2.08 +/- 0.49 L) than predicted values for normal subjects of similar height and age...

Asthma and respiratory symptoms in hospital workers related to dampness and biological contaminants.

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Cox-Ganser, J M; Rao, C Y; Park, J-H; Schumpert, J C; Kreiss, K

2009-08-01

The National Institute for Occupational Safety and Health investigated respiratory symptoms and asthma in relation to damp indoor environments in employees of two hospitals. A cluster of six work-related asthma cases from one hospital department, whose symptoms arose during a time of significant water incursions, led us to conduct a survey of respiratory health in 1171/1834 employees working in the sentinel cases hospital and a nearby hospital without known indoor environmental concerns. We carried out observational assessment of dampness, air, chair, and floor dust sampling for biological contaminants, and investigation of exposure-response associations for about 500 participants. Many participants with post-hire onset asthma reported diagnosis dates in a period of water incursions and renovations. Post-hire asthma and work-related lower respiratory symptoms were positively associated with the dampness score. Work-related lower respiratory symptoms showed monotonically increasing odds ratios with ergosterol, a marker of fungal biomass. Other fungal and bacterial indices, particle counts, cat allergen and latex allergen were associated with respiratory symptoms. Our data imply new-onset of asthma in relation to water damage, and indicate that work-related respiratory symptoms in hospital workers may be associated with diverse biological contaminants. In healthcare facilities with indoor dampness and microbial contamination, possible associations between such conditions and respiratory health effects should be considered. Good building maintenance and housekeeping procedures should lead to improvements in employee respiratory health.

Changed activation, oxygenation, and pain response of chronically painful muscles to repetitive work after training interventions: a randomized controlled trial

DEFF Research Database (Denmark)

Søgaard, Karen; Blangsted, Anne Katrine; Nielsen, Pernille Kofoed

2012-01-01

The aim of this randomized controlled trial was to assess changes in myalgic trapezius activation, muscle oxygenation, and pain intensity during repetitive and stressful work tasks in response to 10 weeks of training. In total, 39 women with a clinical diagnosis of trapezius myalgia were randomly...... levels of pain. SST lowered the relative EMG amplitude by 36%, and decreased pain during resting and working conditions by 52 and 38%, respectively, without affecting trapezius oxygenation. In conclusion, GFT performed as leg-bicycling decreased pain development during repetitive work tasks, possibly due...... assigned to: (1) general fitness training performed as leg-bicycling (GFT); (2) specific strength training of the neck/shoulder muscles (SST) or (3) reference intervention without physical exercise. Electromyographic activity (EMG), tissue oxygenation (near infrared spectroscopy), and pain intensity were...

Identification and Characterization of MicroRNAs from Longitudinal Muscle and Respiratory Tree in Sea Cucumber (Apostichopus japonicus) Using High-Throughput Sequencing.

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Wang, Hongdi; Liu, Shikai; Cui, Jun; Li, Chengze; Hu, Yucai; Zhou, Wei; Chang, Yaqing; Qiu, Xuemei; Liu, Zhanjiang; Wang, Xiuli

2015-01-01

MicroRNAs (miRNAs), as a family of non-coding small RNAs, play important roles in the post-transcriptional regulation of gene expression. Sea cucumber (Apostichopus japonicus) is an important economic species which is widely cultured in East Asia. The longitudinal muscle (LTM) and respiratory tree (RPT) are two important tissues in sea cucumber, playing important roles such as respiration and movement. In this study, we identified and characterized miRNAs in the LTM and RPT of sea cucumber (Apostichopus japonicus) using Illumina HiSeq 2000 platform. A total of 314 and 221 conserved miRNAs were identified in LTM and RPT, respectively. In addition, 27 and 34 novel miRNAs were identified in the LTM and RPT, respectively. A set of 58 miRNAs were identified to be differentially expressed between LTM and RPT. Among them, 9 miRNAs (miR-31a-3p, miR-738, miR-1692, let-7a, miR-72a, miR-100b-5p, miR-31b-5p, miR-429-3p, and miR-2008) in RPT and 7 miRNAs (miR-127, miR-340, miR-381, miR-3543, miR-434-5p, miR-136-3p, and miR-300-3p) in LTM were differentially expressed with foldchange value being greater than 10. A total of 14,207 and 12,174 target genes of these miRNAs were predicted, respectively. Functional analysis of these target genes of miRNAs were performed by GO analysis and pathway analysis. This result provided in this work will be useful for understanding biological characteristics of the LTM and RPT of sea cucumber and assisting molecular breeding of sea cucumber for aquaculture.

Identification and Characterization of MicroRNAs from Longitudinal Muscle and Respiratory Tree in Sea Cucumber (Apostichopus japonicus Using High-Throughput Sequencing.

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Hongdi Wang

Full Text Available MicroRNAs (miRNAs, as a family of non-coding small RNAs, play important roles in the post-transcriptional regulation of gene expression. Sea cucumber (Apostichopus japonicus is an important economic species which is widely cultured in East Asia. The longitudinal muscle (LTM and respiratory tree (RPT are two important tissues in sea cucumber, playing important roles such as respiration and movement. In this study, we identified and characterized miRNAs in the LTM and RPT of sea cucumber (Apostichopus japonicus using Illumina HiSeq 2000 platform. A total of 314 and 221 conserved miRNAs were identified in LTM and RPT, respectively. In addition, 27 and 34 novel miRNAs were identified in the LTM and RPT, respectively. A set of 58 miRNAs were identified to be differentially expressed between LTM and RPT. Among them, 9 miRNAs (miR-31a-3p, miR-738, miR-1692, let-7a, miR-72a, miR-100b-5p, miR-31b-5p, miR-429-3p, and miR-2008 in RPT and 7 miRNAs (miR-127, miR-340, miR-381, miR-3543, miR-434-5p, miR-136-3p, and miR-300-3p in LTM were differentially expressed with foldchange value being greater than 10. A total of 14,207 and 12,174 target genes of these miRNAs were predicted, respectively. Functional analysis of these target genes of miRNAs were performed by GO analysis and pathway analysis. This result provided in this work will be useful for understanding biological characteristics of the LTM and RPT of sea cucumber and assisting molecular breeding of sea cucumber for aquaculture.

Prevalence of Occupational Asthma and Respiratory Symptoms in Foundry Workers

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Servet Kayhan

2013-01-01

Full Text Available This cross-sectional study was conducted in a foundry factory to assess the prevalence of respiratory symptoms and occupational asthma in foundry workers. Physical examination, spirometric evaluation, chest radiograph, and a questionnaire related to respiratory symptoms were performed. Monitoring of peak expiratory flow rates, spirometric reversibility test, and high-resolution computed tomographies were performed for the participants having respiratory symptoms and/or impaired respiratory function test. A total of 347 participants including 286 workers from production department and 61 subjects who worked in nonproduction departments were enrolled in this study. It is found that phlegm (n: 71, 20.46% and cough (n: 52, 14.98% were the most frequent symptoms. The other symptoms were breathlessness (n: 28, 8.06%, chest tightness (n: 14, 4.03%, and wheezing (n: 7, 2.01% . The prevalence of occupational asthma was found to be more frequent among the subjects who worked in the production department (n: 48, 16.78% than the other persons who worked in the nonproduction department (n: 3, 4.91% by chi-square test (P: 0.001. To prevent hazardous respiratory effects of the foundry production, an early diagnosis of occupational asthma is very important. Cessation of cigarette smoking and using of protective masks during the working time should be encouraged.

Severe acute respiratory syndrome in a doctor working at the Prince of Wales Hospital.

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Wong, R S M

2003-06-01

Severe acute respiratory syndrome is a new disease that is highly contagious and is spreading in the local community and worldwide. This report is of a hospital medical officer with severe acute respiratory syndrome. He presented with sudden onset of fever, chills, myalgia, headache, and dizziness in early March 2003. He developed progressive respiratory symptoms and bilateral pulmonary infiltrates during the second week of his illness. Blood tests showed lymphopenia, mild thrombocytopenia, and prolonged activated partial thromboplastin time with normal d-dimer level. His chest condition gradually responded to ribavirin and corticosteroids, and serial chest X-ray showed resolving pulmonary infiltrates. The importance of early diagnosis lies in the potential for early treatment, leading to better response.

Interaction of metabolic and respiratory acidosis with α and β-adrenoceptor stimulation in rat myocardium.

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Biais, Matthieu; Jouffroy, Romain; Carillion, Aude; Feldman, Sarah; Jobart-Malfait, Aude; Riou, Bruno; Amour, Julien

2012-12-01

The effects of acute respiratory versus metabolic acidosis on the myocardium and their consequences on adrenoceptor stimulation remain poorly described. We compared the effects of metabolic and respiratory acidosis on inotropy and lusitropy in rat myocardium and their effects on the responses to α- and β-adrenoceptor stimulations. The effects of acute respiratory and metabolic acidosis (pH 7.10) and their interactions with α and β-adrenoceptor stimulations were studied in isolated rat left ventricular papillary muscle (n=8 per group). Intracellular pH was measured using confocal microscopy and a pH-sensitive fluorophore in isolated rat cardiomyocytes. Data are mean percentages of baseline±SD. Respiratory acidosis induced more pronounced negative inotropic effects than metabolic acidosis did both in isotonic (45±3 versus 63±6%, Prespiratory or metabolic acidosis. The inotropic response to β-adrenergic stimulation was impaired only in metabolic acidosis (137±12 versus 200±33%, Pacidosis. The lusitropic response to β-adrenergic stimulation was not modified by respiratory or metabolic acidosis. Acute metabolic and respiratory acidosis induce different myocardial effects related to different decreases in intracellular pH. Only metabolic acidosis impairs the positive inotropic effect of β-adrenergic stimulation.

Alterations to mitochondrial fatty-acid use in skeletal muscle after chronic exposure to hypoxia depend on metabolic phenotype.

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Malgoyre, Alexandra; Chabert, Clovis; Tonini, Julia; Koulmann, Nathalie; Bigard, Xavier; Sanchez, Hervé

2017-03-01

We investigated the effects of chronic hypoxia on the maximal use of and sensitivity of mitochondria to different substrates in rat slow-oxidative (soleus, SOL) and fast-glycolytic (extensor digitorum longus, EDL) muscles. We studied mitochondrial respiration in situ in permeabilized myofibers, using pyruvate, octanoate, palmitoyl-carnitine (PC), or palmitoyl-coenzyme A (PCoA). The hypophagia induced by hypoxia may also alter metabolism. Therefore, we used a group of pair-fed rats (reproducing the same caloric restriction, as observed in hypoxic animals), in addition to the normoxic control fed ad libitum. The resting respiratory exchange ratio decreased after 21 days of exposure to hypobaric hypoxia (simulated elevation of 5,500 m). The respiration supported by pyruvate and octanoate were unaffected. In contrast, the maximal oxidative respiratory rate for PCoA, the transport of which depends on carnitine palmitoyltransferase 1 (CPT-1), decreased in the rapid-glycolytic EDL and increased in the slow-oxidative SOL, although hypoxia improved affinity for this substrate in both muscle types. PC and PCoA were oxidized similarly in normoxic EDL, whereas chronic hypoxia limited transport at the CPT-1 step in this muscle. The effects of hypoxia were mediated by caloric restriction in the SOL and by hypoxia itself in the EDL. We conclude that improvements in mitochondrial affinity for PCoA, a physiological long-chain fatty acid, would facilitate fatty-acid use at rest after chronic hypoxia independently of quantitative alterations of mitochondria. Conversely, decreasing the maximal oxidation of PCoA in fast-glycolytic muscles would limit fatty-acid use during exercise. NEW & NOTEWORTHY Affinity for low concentrations of long-chain fatty acids (LCFA) in mitochondria skeletal muscles increases after chronic hypoxia. Combined with a lower respiratory exchange ratio, this suggests facility for fatty acid utilization at rest. This fuel preference is related to caloric

Heliox reduces respiratory system resistance in respiratory syncytial virus induced respiratory failure

NARCIS (Netherlands)

Kneyber, Martin C. J.; van Heerde, Marc; Twisk, Jos W. R.; Plotz, Frans B.; Markhors, Dick G.

2009-01-01

Introduction Respiratory syncytial virus (RSV) lower respiratory tract disease is characterised by narrowing of the airways resulting in increased airway resistance, air-trapping and respiratory acidosis. These problems might be overcome using helium-oxygen gas mixture. However, the effect of

Heliox reduces respiratory system resistance in respiratory syncytial virus induced respiratory failure

NARCIS (Netherlands)

Kneijber, M.C.J.; van Heerde, M.; Twisk, J.W.R.; Plotz, F.; Markhorst, D.G.

2009-01-01

Introduction: Respiratory syncytial virus (RSV) lower respiratory tract disease is characterised by narrowing of the airways resulting in increased airway resistance, air-trapping and respiratory acidosis. These problems might be overcome using helium-oxygen gas mixture. However, the effect of

Respiratory diseases and their effects on respiratory function and exercise capacity.

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Van Erck-Westergren, E; Franklin, S H; Bayly, W M

2013-05-01

Given that aerobic metabolism is the predominant energy pathway for most sports, the respiratory system can be a rate-limiting factor in the exercise capacity of fit and healthy horses. Consequently, respiratory diseases, even in mild forms, are potentially deleterious to any athletic performance. The functional impairment associated with a respiratory condition depends on the degree of severity of the disease and the equestrian discipline involved. Respiratory abnormalities generally result in an increase in respiratory impedance and work of breathing and a reduced level of ventilation that can be detected objectively by deterioration in breathing mechanics and arterial blood gas tensions and/or lactataemia. The overall prevalence of airway diseases is comparatively high in equine athletes and may affect the upper airways, lower airways or both. Diseases of the airways have been associated with a wide variety of anatomical and/or inflammatory conditions. In some instances, the diagnosis is challenging because conditions can be subclinical in horses at rest and become clinically relevant only during exercise. In such cases, an exercise test may be warranted in the evaluation of the patient. The design of the exercise test is critical to inducing the clinical signs of the problem and establishing an accurate diagnosis. Additional diagnostic techniques, such as airway sampling, can be valuable in the diagnosis of subclinical lower airway problems that have the capacity to impair performance. As all these techniques become more widely used in practice, they should inevitably enhance veterinarians' diagnostic capabilities and improve their assessment of treatment effectiveness and the long-term management of equine athletes. © 2013 EVJ Ltd.

Mitochondrial Function in an In Vitro Model of Skeletal Muscle of Patients With Protracted Critical Illness and Intensive Care Unit-Acquired Weakness.

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Jiroutková, Kateřina; Krajčová, Adéla; Žiak, Jakub; Fric, Michal; Gojda, Jan; Džupa, Valér; Kalous, Martin; Tůmová, Jana; Trnka, Jan; Duška, František

2017-09-01

Functional mitochondria in skeletal muscle of patients with protracted critical illness and intensive care unit-acquired weakness are depleted, but remaining mitochondria have increased functional capacities of respiratory complexes II and III. This can be an adaptation to relative abundancy of fatty acid over glucose caused by insulin resistance. We hypothesized that the capacity of muscle mitochondria to oxidize fatty acid is increased in protracted critical illness. We assessed fatty acid oxidation (FAO) and mitochondrial functional indices in vitro by using extracellular flux analysis in cultured myotubes obtained by isolating and culturing satellite cells from vastus lateralis muscle biopsy samples from patients with ICU-acquired weakness (n = 6) and age-matched healthy controls (n = 7). Bioenergetic measurements were performed at baseline and after 6 days of exposure to free fatty acids (FFAs). Mitochondrial density in myotubes from ICU patients was 69% of healthy controls ( P = .051). After adjustment to mitochondrial content, there were no differences in adenosine triphosphate (ATP) synthesis or the capacity and coupling of the respiratory chain. FAO capacity in ICU patients was 157% of FAO capacity in controls ( P = .015). In myotubes of ICU patients, unlike healthy controls, the exposure to FFA significantly ( P = .009) increased maximum respiratory chain capacity. In an in vitro model of skeletal muscle of patients with protracted critical illness, we have shown signs of adaptation to increased FAO. Even in the presence of glucose and insulin, elevation of FFAs in the extracellular environment increased maximal capacity of the respiratory chain.

Hamstring muscle length and lumbar lordosis in subjects with different lifestyle and work setting: comparison between individuals with and without chronic low back pain.

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Arab, Amir Massoud; Nourbakhsh, Mohammad Reza

2014-01-01

Shortened hamstring muscle length has been noted in persons with low back pain (LBP). Prolonged sitting postures, such as those adopted during different work settings and sedentary lifestyle has been associated with hamstring shortness and LBP. The purpose of this study was to investigate the effect of lifestyle and work setting on hamstring length and lumbar lordosis in subjects with and without LBP and to identify the relationship between hamstring muscles length and lumbar lordosis in individuals with different lifestyle and work setting. A total of 508 subjects between the ages of 20 and 65 were selected. Subjects were categorized into two groups of individuals with and without LBP. A questionnaire was used to obtain information about the subjects' lifestyle and work setting. Hamstring muscle length and lumbar lordosis were measured in all subjects. The results showed no significant difference in the number of subjects with different work setting or lifestyle in individuals with and without LBP. Hamstring muscle length or lumbar lordosis was not affected by type of work setting and lifestyle. Our data showed significant difference in hamstring length and no significant difference in lumbar lordosis between subjects with and without LBP in all categories. Lumbar lordosis was not different between individuals with and without hamstring tightness in normal and LBP subjects with different work setting and lifestyle. The findings of this study did not support the assumption that work setting and sedentary lifestyle would lead to hamstring tightness in subjects with LBP. It seems that work setting and lifestyle was not a contributing factor for hamstring tightness in subjects with LBP.

The effects of a passive exoskeleton on muscle activity, discomfort and endurance time in forward bending work

NARCIS (Netherlands)

Bosch, T.; Eck, J. van; Knitel, K.; Looze, M.P. de

2016-01-01

Exoskeletons may form a new strategy to reduce the risk of developing low back pain in stressful jobs. In the present study we examined the potential of a so-called passive exoskeleton on muscle activity, discomfort and endurance time in prolonged forward-bended working postures.Eighteen subjects

Inspiratory muscle training in patients with Amyotrophic Lateral Sclerosis: A systematic review.

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Eidenberger, Margit; Nowotny, Silvia

2014-01-01

Amyotrophic Lateral Sclerosis is a neurodegenerative disease with rapid involvement of the inspiratory muscles, leading to respiratory insufficiency. Death often occurs by aspiration and pneumonia. Endurance- and strength therapy within ALS are discussed controversially. To review the current literature to assess the efficacy of inspiratory muscle training for ALS. Systematic review, using databases as PubMed, PEDro, Cochrane and Google Scholar. Inspiratory muscle training vs. sham training or inspiratory muscle training alone. Inspiratory muscle strength, dyspnoea, quality of life and survival time. Four studies could be included in this review, two RCT's, one pre-experimental study and one with a historical control group. In total 73 patients underwent inspiratory muscle training. Studies varied in onset of the training, the training protocol and the outcomes measured. At time, there is limited evidence that inspiratory muscle training leads to strengthening of inspiratory muscles in ALS. Improvements made were minor, in only a few parameters and also in control groups. Survival time was significantly longer in the experimental group in one study. Interesting suppositions (diaphragm training vs. other IM training, improvement of chest wall and lung compliance) need to be examined in robustly designed future trials, defining exact therapeutic windows and interventions.

Partial rupture of the quadriceps muscle in a child

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Aydemir Gokhan

2010-09-01

Full Text Available Abstract Background The quadriceps femoris muscle ruptures usually occur in the middle-aged population. We present a 4-year-old patient with partial rupture of the quadriceps femoris muscle. To our knowledge, this is the youngest patient reported with a quadriceps femoris muscle rupture. Case Presentation A 4-year-old girl admitted to our clinic with left knee pain and limitation in knee movements. Her father reported that she felt pain while jumping on sofa. There was no direct trauma to thigh or knee. We located a palpable soft tissue swelling at distal anterolateral side of thigh. The history revealed that 10 days ago the patient was treated for upper tract respiratory infection with intramuscular Clindamycin for 7 days. When we consulted the patient with her previous doctor and nurse, we learnt that multiple daily injections might be injected to same side of left thigh. MRI showed a partial tear of vastus lateralis muscle matching with the injection sites. The patient treated with long leg half-casting for three weeks. Clinical examination and knee flexion had good results with conservative treatment. Conclusions Multiple intramuscular injections may contribute to damage muscles and make prone to tears with muscle contractions. Doctors and nurses must be cautious to inject from different parts of both thighs.

Physical inactivity and muscle oxidative capacity in humans.

Science.gov (United States)

Gram, Martin; Dahl, Rannvá; Dela, Flemming

2014-01-01

Physical inactivity is associated with a high prevalence of type 2 diabetes and is an independent predictor of mortality. It is possible that the detrimental effects of physical inactivity are mediated through a lack of adequate muscle oxidative capacity. This short review will cover the present literature on the effects of different models of inactivity on muscle oxidative capacity in humans. Effects of physical inactivity include decreased mitochondrial content, decreased activity of oxidative enzymes, changes in markers of oxidative stress and a decreased expression of genes and contents of proteins related to oxidative phosphorylation. With such a substantial down-regulation, it is likely that a range of adenosine triphosphate (ATP)-dependent pathways such as calcium signalling, respiratory capacity and apoptosis are affected by physical inactivity. However, this has not been investigated in humans, and further studies are required to substantiate this hypothesis, which could expand our knowledge of the potential link between lifestyle-related diseases and muscle oxidative capacity. Furthermore, even though a large body of literature reports the effect of physical training on muscle oxidative capacity, the adaptations that occur with physical inactivity may not always be opposite to that of physical training. Thus, it is concluded that studies on the effect of physical inactivity per se on muscle oxidative capacity in functional human skeletal muscle are warranted.

Respiratory symptoms and lung function in bauxite miners.

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Beach, J R; de Klerk, N H; Fritschi, L; Sim, M R; Musk, A W; Benke, G; Abramson, M J; McNeil, J J

2001-09-01

To determine whether cumulative bauxite exposure is associated with respiratory symptoms or changes in lung function in a group of bauxite miners. Current employees at three bauxite mines in Australia were invited to participate in a survey comprising: questionnaire on demographic details, respiratory symptoms, and work history; skin prick tests for four common aeroallergens; and spirometry. A task exposure matrix was constructed for bauxite exposure in all tasks in all jobs based on monitoring data. Data were examined for associations between cumulative bauxite exposure, and respiratory symptoms and lung function, by regression analyses. The participation rate was 86%. Self-reported work-related respiratory symptoms were reported by relatively few subjects (1.5%-11.8%). After adjustment for age and smoking no significant differences in the prevalence of respiratory symptoms were identified between subjects, in the quartiles of cumulative bauxite exposure distribution. The forced expiratory volume in I s (FEV1) of the exposed group was found to be significantly lower than that for the unexposed group. After adjustment for age, height, and smoking there were no statistically significant differences between quartiles in FEVI, forced vital capacity (FVC) and FEVl/FVC ratio. These data provide little evidence of a serious adverse effect on respiratory health associated with exposure to bauxite in an open-cut bauxite mine in present day conditions.

Selective muscle fiber loss and molecular compensation in mitochondrial myopathy due to TK2 deficiency.

Science.gov (United States)

Vilà, Maya R; Villarroya, Joan; García-Arumí, Elena; Castellote, Amparo; Meseguer, Anna; Hirano, Michio; Roig, Manuel

2008-04-15

A 12-year-old patient with mitochondrial DNA (mtDNA) depletion syndrome due to TK2 gene mutations has been evaluated serially over the last 10 years. We observed progressive muscle atrophy with selective loss of type 2 muscle fibers and, despite severe depletion of mtDNA, normal activities of respiratory chain (RC) complexes and levels of COX II mitochondrial protein in the remaining muscle fibers. These results indicate that compensatory mechanisms account for the slow progression of the disease. Identification of factors that ameliorate mtDNA depletion may reveal new therapeutic targets for these devastating disorders.

Human Respiratory Syncytial Virus and Human Metapneumovirus

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Luciana Helena Antoniassi da Silva

2009-08-01

Full Text Available The human respiratory syncytial virus (hRSV and the human metapneumovírus (hMPV are main etiological agents of acute respiratory infections (ARI. The ARI is an important cause of childhood morbidity and mortality worldwide.  hRSV and hMPV are members of the Paramyxoviridae. They are enveloped, non-segmented viruses, with negative-sense single stranded genomes. Respiratory syncytial virus (hRSV is the best characterized agent viral of this group, associated with respiratory diseases in lower respiratory tract. Recently, a new human pathogen belonging to the subfamily Pneumovirinae was identified, the human metapneumovirus (hMPV, which is structurally similar to the hRSV, in genomic organization, viral structure, antigenicity and clinical symptoms.  The subfamily Pneumovirinae contains two genera: genus Pneumovirus contains hRSV, the bovine (bRSV, as well as the ovine and caprine respiratory syncytial virus and pneumonia virus of mice, the second genus Metapneumovirus, consists of avian metapneumovirus (aMPV and human metapneumovirus (hMPV. In this work, we present a brief narrative review of the literature on important aspects of the biology, epidemiology and clinical manifestations of infections by two respiratory viruses.

Muscles and their myokines

DEFF Research Database (Denmark)

Pedersen, Bente Klarlund

2011-01-01

In the past, the role of physical activity as a life-style modulating factor has been considered as that of a tool to balance energy intake. Although it is important to avoid obesity, physical inactivity should be discussed in a much broader context. There is accumulating epidemiological evidence...... or endocrine effects should be classified as 'myokines'. Given that skeletal muscle is the largest organ in the human body, our discovery that contracting skeletal muscle secretes proteins sets a novel paradigm: skeletal muscle is an endocrine organ producing and releasing myokines, which work in a hormone......-like fashion, exerting specific endocrine effects on other organs. Other myokines work via paracrine mechanisms, exerting local effects on signalling pathways involved in muscle metabolism. It has been suggested that myokines may contribute to exercise-induced protection against several chronic diseases....

Force encoding in muscle spindles during stretch of passive muscle.

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Kyle P Blum

2017-09-01

Full Text Available Muscle spindle proprioceptive receptors play a primary role in encoding the effects of external mechanical perturbations to the body. During externally-imposed stretches of passive, i.e. electrically-quiescent, muscles, the instantaneous firing rates (IFRs of muscle spindles are associated with characteristics of stretch such as length and velocity. However, even in passive muscle, there are history-dependent transients of muscle spindle firing that are not uniquely related to muscle length and velocity, nor reproduced by current muscle spindle models. These include acceleration-dependent initial bursts, increased dynamic response to stretch velocity if a muscle has been isometric, and rate relaxation, i.e., a decrease in tonic IFR when a muscle is held at a constant length after being stretched. We collected muscle spindle spike trains across a variety of muscle stretch kinematic conditions, including systematic changes in peak length, velocity, and acceleration. We demonstrate that muscle spindle primary afferents in passive muscle fire in direct relationship to muscle force-related variables, rather than length-related variables. Linear combinations of whole muscle-tendon force and the first time derivative of force (dF/dt predict the entire time course of transient IFRs in muscle spindle Ia afferents during stretch (i.e., lengthening of passive muscle, including the initial burst, the dynamic response to lengthening, and rate relaxation following lengthening. Similar to acceleration scaling found previously in postural responses to perturbations, initial burst amplitude scaled equally well to initial stretch acceleration or dF/dt, though later transients were only described by dF/dt. The transient increase in dF/dt at the onset of lengthening reflects muscle short-range stiffness due to cross-bridge dynamics. Our work demonstrates a critical role of muscle cross-bridge dynamics in history-dependent muscle spindle IFRs in passive muscle

Force encoding in muscle spindles during stretch of passive muscle.

Science.gov (United States)

Blum, Kyle P; Lamotte D'Incamps, Boris; Zytnicki, Daniel; Ting, Lena H

2017-09-01

Muscle spindle proprioceptive receptors play a primary role in encoding the effects of external mechanical perturbations to the body. During externally-imposed stretches of passive, i.e. electrically-quiescent, muscles, the instantaneous firing rates (IFRs) of muscle spindles are associated with characteristics of stretch such as length and velocity. However, even in passive muscle, there are history-dependent transients of muscle spindle firing that are not uniquely related to muscle length and velocity, nor reproduced by current muscle spindle models. These include acceleration-dependent initial bursts, increased dynamic response to stretch velocity if a muscle has been isometric, and rate relaxation, i.e., a decrease in tonic IFR when a muscle is held at a constant length after being stretched. We collected muscle spindle spike trains across a variety of muscle stretch kinematic conditions, including systematic changes in peak length, velocity, and acceleration. We demonstrate that muscle spindle primary afferents in passive muscle fire in direct relationship to muscle force-related variables, rather than length-related variables. Linear combinations of whole muscle-tendon force and the first time derivative of force (dF/dt) predict the entire time course of transient IFRs in muscle spindle Ia afferents during stretch (i.e., lengthening) of passive muscle, including the initial burst, the dynamic response to lengthening, and rate relaxation following lengthening. Similar to acceleration scaling found previously in postural responses to perturbations, initial burst amplitude scaled equally well to initial stretch acceleration or dF/dt, though later transients were only described by dF/dt. The transient increase in dF/dt at the onset of lengthening reflects muscle short-range stiffness due to cross-bridge dynamics. Our work demonstrates a critical role of muscle cross-bridge dynamics in history-dependent muscle spindle IFRs in passive muscle lengthening conditions

Differentiated muscles are mandatory for gas-filling of the Drosophila airway system

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Yiwen Wang

2015-12-01

Full Text Available At the end of development, organs acquire functionality, thereby ensuring autonomy of an organism when it separates from its mother or a protective egg. In insects, respiratory competence starts when the tracheal system fills with gas just before hatching of the juvenile animal. Cellular and molecular mechanisms of this process are not fully understood. Analyses of the phenotype of Drosophila embryos with malformed muscles revealed that they fail to gas-fill their tracheal system. Indeed, we show that major regulators of muscle formation like Lame duck and Blown fuse are important, while factors involved in the development of subsets of muscles including cardiac and visceral muscles are dispensable for this process, suggesting that somatic muscles (or parts of them are essential to enable tracheal terminal differentiation. Based on our phenotypic data, we assume that somatic muscle defect severity correlates with the penetrance of the gas-filling phenotype. This argues that a limiting molecular or mechanical muscle-borne signal tunes tracheal differentiation. We think that in analogy to the function of smooth muscles in vertebrate lungs, a balance of physical forces between muscles and the elasticity of tracheal walls may be decisive for tracheal terminal differentiation in Drosophila.

Respiratory symptoms as health status indicators in workers at ceramics manufacturing facilities.

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Rondon, Edilaura Nunes; Silva, Regina Maria Veras Gonçalves da; Botelho, Clovis

2011-01-01

To assess the prevalence of respiratory symptoms and their association with sociodemographic variables and with the characteristics of the work environment. A cross-sectional study comprising 464 workers employed at ceramics manufacturing facilities located in the city of Várzea Grande, Brazil. Data were collected by means of a questionnaire comprising questions regarding sociodemographic variables, work environment characteristics, and respiratory symptoms. Data were analyzed by means of prevalence ratios and their respective 95% CIs between the dependent variable (respiratory symptoms) and the other explanatory variables. In the multivariate analysis, two hierarchical models were built, the response variables being "all respiratory symptoms" and "severe respiratory symptoms". In the sample studied, the prevalence of "all respiratory symptoms" was 78%, whereas that of "severe respiratory symptoms" was 35%. The factors associated with "all respiratory symptoms" were gender, age bracket, level of education, type of occupation, exposure to dust, and exposure to chemical products. The factors associated with "severe respiratory symptoms" were level of education, exposure to dust, and exposure to chemical products. Our results indicate the presence of upper and lower airway disease in the population studied.

Cardio-respiratory interactions and relocation of heartbeats within the respiratory cycle during spontaneous and paced breathing

International Nuclear Information System (INIS)

Lopes, T C; Beda, A; Granja-Filho, P C N; Jandre, F C; Giannella-Neto, A

2011-01-01

The capability of respiratory sinus arrhythmia (RSA) to generate privileged locations for the occurrence of R-peaks within the respiratory cycle has been questioned in recent works, challenging the hypothesis that RSA might play a role in improving pulmonary gas exchange. We assessed such a capability submitting healthy humans to spontaneous and paced breathing (SB and PB) protocols, estimating the fraction of beats occurring during inspiration, at low, medium, and high respiratory volumes, and during the first and second half of inspiration and expiration. Then, the same fractions were computed assuming a random uniform distribution of heartbeats, and the differences were compared. The results found are as follows: (1) during PB at 6 rpm, heartbeats redistribute toward inspiration; (2) during SB and PB at 12 rpm, heartbeats tend to cluster when respiratory volume is high; (3) since such redistributions are limited in magnitude, it is possible that its physiological relevance is marginal, for instance, in terms of within-cycle variations in lung perfusion; (4) two groups of subjects with considerably different levels of RSA showed similar redistribution of heartbeats, suggesting that this phenomenon might be an underlying effect of the overall cardio-respiratory interactions, and not directly of RSA

Respiratory chain complex I deficiency due to NDUFA12 mutations as a new cause of Leigh syndrome

DEFF Research Database (Denmark)

Ostergaard, Elsebet; Rodenburg, Richard J; van den Brand, Mariël

2011-01-01

This study investigated a girl with Leigh syndrome born to first-cousin parents of Pakistani descent with an isolated respiratory chain complex I deficiency in muscle and fibroblasts. Her early development was delayed, and from age 2 years she started losing motor abilities. Cerebral MRI showed...

Effect of physiotherapy in respiratory diseases during healing stays

OpenAIRE

Schneebergerová, Jana

2013-01-01

Title: Effect of physiotherapy in respiratory diseases during healing stays Objective: The main objective of this work is to analyze the importance of physiotherapy as one of the treatments used in the care of pediatric patients with bronchial asthma. Method: In the theoretic part of the dissertation anatomy and physiology of the respiratory tract, respiratory biomechanics, problems of asthma bronchiale, possibilities of asthma treatment, prevention and improvement of quality of life in child...

Tei index in neonatal respiratory distress and perinatal asphyxia

OpenAIRE

Ahmed Anwer Attia Khattab

2015-01-01

Cardiovascular compromise is a common complication of neonatal respiratory distress and perinatal asphyxia. Tei index is a Doppler-derived index for the assessment of overall left ventricular function that combines systolic and diastolic time intervals. Aim: Assess the role of MPI versus cardiac troponin I as early indicator of hypoxic cardiac damage in neonates with respiratory distress or perinatal asphyxia. The present work was conducted on forty neonates, 15 with neonatal respiratory dist...

Respiratory mechanics in infants with severe bronchiolitis on controlled mechanical ventilation.

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Cruces, Pablo; González-Dambrauskas, Sebastián; Quilodrán, Julio; Valenzuela, Jorge; Martínez, Javier; Rivero, Natalia; Arias, Pablo; Díaz, Franco

2017-10-06

Analysis of respiratory mechanics during mechanical ventilation (MV) is able to estimate resistive, elastic and inertial components of the working pressure of the respiratory system. Our aim was to discriminate the components of the working pressure of the respiratory system in infants on MV with severe bronchiolitis admitted to two PICU's. Infants younger than 1 year old with acute respiratory failure caused by severe bronchiolitis underwent neuromuscular blockade, tracheal intubation and volume controlled MV. Shortly after intubation studies of pulmonary mechanics were performed using inspiratory and expiratory breath hold. The maximum inspiratory and expiratory flow (QI and QE) as well as peak inspiratory (PIP), plateau (PPL) and total expiratory pressures (tPEEP) were measured. Inspiratory and expiratory resistances (RawI and RawE) and Time Constants (K TI and K TE ) were calculated. We included 16 patients, of median age 2.5 (1-5.8) months. Bronchiolitis due to respiratory syncytial virus was the main etiology (93.8%) and 31.3% had comorbidities. Measured respiratory pressures were PIP 29 (26-31), PPL 24 (20-26), tPEEP 9 [8-11] cmH2O. Elastic component of the working pressure was significantly higher than resistive and both higher than threshold (tPEEP - PEEP) (P mechanics of infants with severe bronchiolitis receiving MV shows that the elastic component of the working pressure of the respiratory system is the most important. The elastic and resistive components in conjunction with flow profile are characteristic of restrictive diseases. A better understanding of lung mechanics in this group of patients may lead to change the traditional ventilatory approach to severe bronchiolitis.

Stereotypic Laryngeal and Respiratory Motor Patterns Generate Different Call Types in Rat Ultrasound Vocalization

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RIEDE, TOBIAS

2014-01-01

Rodents produce highly variable ultrasound whistles as communication signals unlike many other mammals, who employ flow-induced vocal fold oscillations to produce sound. The role of larynx muscles in controlling sound features across different call types in ultrasound vocalization (USV) was investigated using laryngeal muscle electromyographic (EMG) activity, subglottal pressure measurements and vocal sound output in awake and spontaneously behaving Sprague–Dawley rats. Results support the hypothesis that glottal shape determines fundamental frequency. EMG activities of thyroarytenoid and cricothyroid muscles were aligned with call duration. EMG intensity increased with fundamental frequency. Phasic activities of both muscles were aligned with fast changing fundamental frequency contours, for example in trills. Activities of the sternothyroid and sternohyoid muscles, two muscles involved in vocal production in other mammals, are not critical for the production of rat USV. To test how stereotypic laryngeal and respiratory activity are across call types and individuals, sets of ten EMG and subglottal pressure parameters were measured in six different call types from six rats. Using discriminant function analysis, on average 80% of parameter sets were correctly assigned to their respective call type. This was significantly higher than the chance level. Since fundamental frequency features of USV are tightly associated with stereotypic activity of intrinsic laryngeal muscles and muscles contributing to build-up of subglottal pressure, USV provide insight into the neurophysiological control of peripheral vocal motor patterns. PMID:23423862

Nonshivering thermogenesis in king penguin chicks. I. Role of skeletal muscle.

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Duchamp, C; Barré, H; Rouanet, J L; Lanni, A; Cohen-Adad, F; Berne, G; Brebion, P

1991-12-01

In cold-acclimatized (CA) king penguin chicks exhibiting nonshivering thermogenesis (NST), protein content and cytochrome oxidase (CO) activity of tissue homogenates were measured together with protein content, CO, and respiration rates of isolated mitochondria from skeletal muscle (gastrocnemius and pectoralis) and liver. The comparison was made with chicks reared at thermoneutrality (TN) for at least 3 wk. In CA chicks showing a NST despite the lack of brown adipose tissue, an increase in thermogenic capacity was observed in skeletal muscle in which the oxidative capacity rose (+28% and +50% in gastrocnemius and pectoralis muscles, respectively), whereas no change occurred in the liver. Oxidative capacity of skeletal muscle increased together with the development of mitochondrial inner membrane plus cristae in muscles of CA chicks contrary to their TN littermates (+30 to +50%). Subsarcolemmal mitochondria of CA chicks had a higher protein content (+65% in gastrocnemius muscle) and higher oxidative capacities than in controls. The lower respiratory control ratio of these mitochondria might result from a low ADP phosphorylation rate. No change occurred in the intermyofibrillar fraction nor in liver mitochondria. These findings together with earlier results obtained in cold-acclimated ducklings indicate the marked and suited adaptation of skeletal muscle and in particular of subsarcolemmal mitochondria allowing them to play a role in NST.

Effect of singing on respiratory function, voice, and mood after quadriplegia: a randomized controlled trial.

Science.gov (United States)

Tamplin, Jeanette; Baker, Felicity A; Grocke, Denise; Brazzale, Danny J; Pretto, Jeffrey J; Ruehland, Warren R; Buttifant, Mary; Brown, Douglas J; Berlowitz, David J

2013-03-01

To explore the effects of singing training on respiratory function, voice, mood, and quality of life for people with quadriplegia. Randomized controlled trial. Large, university-affiliated public hospital, Victoria, Australia. Participants (N=24) with chronic quadriplegia (C4-8, American Spinal Injury Association grades A and B). The experimental group (n=13) received group singing training 3 times weekly for 12 weeks. The control group (n=11) received group music appreciation and relaxation for 12 weeks. Assessments were conducted pre, mid-, immediately post-, and 6-months postintervention. Standard respiratory function testing, surface electromyographic activity from accessory respiratory muscles, sound pressure levels during vocal tasks, assessments of voice quality (Perceptual Voice Profile, Multidimensional Voice Profile), and Voice Handicap Index, Profile of Mood States, and Assessment of Quality of Life instruments. The singing group increased projected speech intensity (P=.028) and maximum phonation length (P=.007) significantly more than the control group. Trends for improvements in respiratory function, muscle strength, and recruitment were also evident for the singing group. These effects were limited by small sample sizes with large intersubject variability. Both groups demonstrated an improvement in mood (P=.002), which was maintained in the music appreciation and relaxation group after 6 months (P=.017). Group music therapy can have a positive effect on not only physical outcomes, but also can improve mood, energy, social participation, and quality of life for an at-risk population, such as those with quadriplegia. Specific singing therapy can augment these general improvements by improving vocal intensity. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Postoperative inspiratory muscle training in addition to breathing exercises and early mobilization improves oxygenation in high-risk patients after lung cancer surgery: a randomized controlled trial.

Science.gov (United States)

Brocki, Barbara Cristina; Andreasen, Jan Jesper; Langer, Daniel; Souza, Domingos Savio R; Westerdahl, Elisabeth

2016-05-01

The aim was to investigate whether 2 weeks of inspiratory muscle training (IMT) could preserve respiratory muscle strength in high-risk patients referred for pulmonary resection on the suspicion of or confirmed lung cancer. Secondarily, we investigated the effect of the intervention on the incidence of postoperative pulmonary complications. The study was a single-centre, parallel-group, randomized trial with assessor blinding and intention-to-treat analysis. The intervention group (IG, n = 34) underwent 2 weeks of postoperative IMT twice daily with 2 × 30 breaths on a target intensity of 30% of maximal inspiratory pressure, in addition to standard postoperative physiotherapy. Standard physiotherapy in the control group (CG, n = 34) consisted of breathing exercises, coughing techniques and early mobilization. We measured respiratory muscle strength (maximal inspiratory/expiratory pressure, MIP/MEP), functional performance (6-min walk test), spirometry and peripheral oxygen saturation (SpO2), assessed the day before surgery and again 3-5 days and 2 weeks postoperatively. Postoperative pulmonary complications were evaluated 2 weeks after surgery. The mean age was 70 ± 8 years and 57.5% were males. Thoracotomy was performed in 48.5% (n = 33) of cases. No effect of the intervention was found regarding MIP, MEP, lung volumes or functional performance at any time point. The overall incidence of pneumonia was 13% (n = 9), with no significant difference between groups [IG 6% (n = 2), CG 21% (n = 7), P = 0.14]. An improved SpO2 was found in the IG on the third and fourth postoperative days (Day 3: IG 93.8 ± 3.4 vs CG 91.9 ± 4.1%, P = 0.058; Day 4: IG 93.5 ± 3.5 vs CG 91 ± 3.9%, P = 0.02). We found no association between surgical procedure (thoracotomy versus thoracoscopy) and respiratory muscle strength, which was recovered in both groups 2 weeks after surgery. Two weeks of additional postoperative IMT, compared with standard physiotherapy alone, did not preserve

Molecular Mechanisms for Age-Associated Mitochondrial Deficiency in Skeletal Muscle

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Akira Wagatsuma

2012-01-01

Full Text Available The abundance, morphology, and functional properties of mitochondria decay in skeletal muscle during the process of ageing. Although the precise mechanisms remain to be elucidated, these mechanisms include decreased mitochondrial DNA (mtDNA repair and mitochondrial biogenesis. Mitochondria possess their own protection system to repair mtDNA damage, which leads to defects of mtDNA-encoded gene expression and respiratory chain complex enzymes. However, mtDNA mutations have shown to be accumulated with age in skeletal muscle. When damaged mitochondria are eliminated by autophagy, mitochondrial biogenesis plays an important role in sustaining energy production and physiological homeostasis. The capacity for mitochondrial biogenesis has shown to decrease with age in skeletal muscle, contributing to progressive mitochondrial deficiency. Understanding how these endogenous systems adapt to altered physiological conditions during the process of ageing will provide a valuable insight into the underlying mechanisms that regulate cellular homeostasis. Here we will summarize the current knowledge about the molecular mechanisms responsible for age-associated mitochondrial deficiency in skeletal muscle. In particular, recent findings on the role of mtDNA repair and mitochondrial biogenesis in maintaining mitochondrial functionality in aged skeletal muscle will be highlighted.

Chronic intrinsic transient tracheal occlusion elicits diaphragmatic muscle fiber remodeling in conscious rodents.

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Barbara K Smith

Full Text Available BACKGROUND: Although the prevalence of inspiratory muscle strength training has increased in clinical medicine, its effect on diaphragm fiber remodeling is not well-understood and no relevant animal respiratory muscle strength training-rehabilitation experimental models exist. We tested the postulate that intrinsic transient tracheal occlusion (ITTO conditioning in conscious animals would provide a novel experimental model of respiratory muscle strength training, and used significant increases in diaphragmatic fiber cross-sectional area (CSA as the primary outcome measure. We hypothesized that ITTO would increase costal diaphragm fiber CSA and further hypothesized a greater duration and magnitude of occlusions would amplify remodeling. METHODOLOGY/PRINCIPAL FINDINGS: Sprague-Dawley rats underwent surgical placement of a tracheal cuff and were randomly assigned to receive daily either 10-minute sessions of ITTO, extended-duration, 20-minute ITTO (ITTO-20, partial obstruction with 50% of cuff inflation pressure (ITTO-PAR or observation (SHAM over two weeks. After the interventions, fiber morphology, myosin heavy chain composition and CSA were examined in the crural and ventral, medial, and dorsal costal regions. In the medial costal diaphragm, with ITTO, type IIx/b fibers were 26% larger in the medial costal diaphragm (p<0.01 and 24% larger in the crural diaphragm (p<0.05. No significant changes in fiber composition or morphology were detected. ITTO-20 sessions also yielded significant increases in medial costal fiber cross-sectional area, but the effects were not greater than those elicited by 10-minute sessions. On the other hand, ITTO-PAR resulted in partial airway obstruction and did not generate fiber hypertrophy. CONCLUSIONS/SIGNIFICANCE: The results suggest that the magnitude of the load was more influential in altering fiber cross-sectional area than extended-duration conditioning sessions. The results also indicated that ITTO was

Effects of the workplace health promotion activities soccer and zumba on muscle pain, work ability and perceived physical exertion among female hospital employees

DEFF Research Database (Denmark)

Barene, Svein; Krustrup, Peter; Holtermann, Andreas

2014-01-01

-randomized into two training groups, and a control group. The training was conducted outside working hours as two-three 1-h sessions per week for the first 12 weeks, and continued as one-two 1-h sessions per week for the last 28 weeks. Muscle pain intensity and duration, work ability, and RPE during work were......Objectives: This 40-week workplace physical training RCT investigated the effect of soccer and Zumba, respectively, on muscle pain intensity and duration, work ability, and rating of perceived exertion (RPE) during work among female hospital employees. Methods: 107 hospital employees were cluster...... group (-1.9, 95% CI, -3.2, -0.7, P=0.002, eta squared=0.092) showed a reduction after 40 weeks referencing the control group. After 40 weeks, both the soccer (-16.4 days, 95% CI, -29.6, -3.2, P4.2, P

Muscle activity pattern dependent pain development and alleviation.

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Sjøgaard, Gisela; Søgaard, Karen

2014-12-01

Muscle activity is for decades considered to provide health benefits irrespectively of the muscle activity pattern performed and whether it is during e.g. sports, transportation, or occupational work tasks. Accordingly, the international recommendations for public health-promoting physical activity do not distinguish between occupational and leisure time physical activity. However, in this body of literature, attention has not been paid to the extensive documentation on occupational physical activity imposing a risk of impairment of health - in particular musculoskeletal health in terms of muscle pain. Focusing on muscle activity patterns and musculoskeletal health it is pertinent to elucidate the more specific aspects regarding exposure profiles and body regional pain. Static sustained muscle contraction for prolonged periods often occurs in the neck/shoulder area during occupational tasks and may underlie muscle pain development in spite of rather low relative muscle load. Causal mechanisms include a stereotype recruitment of low threshold motor units (activating type 1 muscle fibers) characterized by a lack of temporal as well as spatial variation in recruitment. In contrast during physical activities at leisure and sport the motor recruitment patterns are more dynamic including regularly relatively high muscle forces - also activating type 2 muscles fibers - as well as periods of full relaxation even of the type 1 muscle fibers. Such activity is unrelated to muscle pain development if adequate recovery is granted. However, delayed muscle soreness may develop following intensive eccentric muscle activity (e.g. down-hill skiing) with peak pain levels in thigh muscles 1-2 days after the exercise bout and a total recovery within 1 week. This acute pain profile is in contrast to the chronic muscle pain profile related to repetitive monotonous work tasks. The painful muscles show adverse functional, morphological, hormonal, as well as metabolic characteristics. Of

Exercise is more than medicine:The working age population’s well-being and productivity

Institute of Scientific and Technical Information of China (English)

Gisela Sjøgaard; Jeanette Reffstrup Christensen; Just Bendix Justesen; Mike Murray; Tina Dalager; Gitte Hansen Fredslund; Karen Søgaard

2016-01-01

Background: Physical activity (PA) includes muscle activity during exercise, manual work, and leisure time activities including sport. Conflicting results exist regarding health effects of PA that may deteriorate with manual work and elite sports, but improve when performed in moderation in accordance with international guidelines and may additionally enhance well-being and productivity. Methods: In Denmark 15 randomized controlled trials have been conducted, introducing exercise at the workplace enrolling>3500 workers. The interventions lasted from 10 to 52 weeks and offered~1 h weekly supervised exercise during working hours according to the concept of intelligent physical exercise training (IPET) that is based on evidenced sports sciences training principles and tailored to work exposure, employee health status, and physical capacity. Questionnaire surveys and health checks including blood and muscle sampling were performed at baseline and follow-up. The job groups included: office and computer workers, dentists, industrial technicians, cleaning personnel, health care workers, construction workers, and fighter/helicopter pilots. Results: In all job groups significant improvements were documented regarding health outcomes. These were job group specific:neck pain was reduced among office and computer workers, dentists, industrial laboratory technicians, health care workers as well as fighter pilots. Cardio-respiratory fitness—a health risk indicator for cardio-metabolic diseases—was improved among office and computer workers, health care workers, and construction workers. Additionally, other improvements were evidenced such as increased muscle strength and balance control. Importantly, productivity increased with improved muscle strength and decreased body mass index. Conclusion: IPET does enhance health if an exercise program with evidenced efficacy is implemented by expert trainees with support of the employer. Accordingly, in every study group outcomes of

Acute effects of inspiratory muscle warm-up on pulmonary function in healthy subjects.

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Özdal, Mustafa

2016-06-15

The acute effects of inspiratory muscle warm-up on pulmonary functions were examined in 26 healthy male subjects using the pulmonary function test (PFT) in three different trials. The control trial (CON) did not involve inspiratory muscle warm-up, while the placebo (IMWp) and experimental (IMW) trials involved inspiratory muscle warm-up. There were no significant changes between the IMWp and CON trials (p>0.05). All the PFT measurements, including slow vital capacity, inspiratory vital capacity, forced vital capacity, forced expiratory volume in one second, maximal voluntary ventilation, and maximal inspiratory pressure were significantly increased by 3.55%, 12.52%, 5.00%, 2.75%, 2.66%, and 7.03% respectively, in the subjects in the IMW trial than those in the CON trial (pcooperation of the upper thorax, neck, and respiratory muscles, and increased level of reactive O2 species in muscle tissue, and potentially improvement of muscle O2 delivery-to-utilization. However, further investigation is required to determine the precise mechanisms responsible from among these candidates. Copyright © 2016 Elsevier B.V. All rights reserved.

Muscle-specific expression of hypoxia-inducible factor in human skeletal muscle

DEFF Research Database (Denmark)

Mounier, Rémi; Pedersen, Bente Klarlund; Plomgaard, Peter

2010-01-01

fibres that possess unique patterns of protein and gene expression, producing different capillarization and energy metabolism systems. In this work, we analysed HIF-1alpha mRNA and protein expression related to the fibre-type composition in untrained human skeletal muscle by obtaining muscle biopsies...... from triceps brachii (characterized by a high proportion of type II fibres), from soleus (characterized by a high proportion of type I fibres) and from vastus lateralis (characterized by an equal proportion of type I and II fibres). The hypothesis was that type I muscle fibres would have lower HIF-1......alpha protein level. Interestingly, none of the HIF-1alpha target genes, like the most studied angiogenic factor involved in muscle angiogenesis, vascular endothelial growth factor (VEGF), exhibited a muscle fibre-specific-related mRNA expression at rest in normoxia. However, soleus presented...

Inter-fraction variations in respiratory motion models

Energy Technology Data Exchange (ETDEWEB)

McClelland, J R; Modat, M; Ourselin, S; Hawkes, D J [Centre for Medical Image Computing, University College London (United Kingdom); Hughes, S; Qureshi, A; Ahmad, S; Landau, D B, E-mail: j.mcclelland@cs.ucl.ac.uk [Department of Oncology, Guy' s and St Thomas' s Hospitals NHS Trust, London (United Kingdom)

2011-01-07

Respiratory motion can vary dramatically between the planning stage and the different fractions of radiotherapy treatment. Motion predictions used when constructing the radiotherapy plan may be unsuitable for later fractions of treatment. This paper presents a methodology for constructing patient-specific respiratory motion models and uses these models to evaluate and analyse the inter-fraction variations in the respiratory motion. The internal respiratory motion is determined from the deformable registration of Cine CT data and related to a respiratory surrogate signal derived from 3D skin surface data. Three different models for relating the internal motion to the surrogate signal have been investigated in this work. Data were acquired from six lung cancer patients. Two full datasets were acquired for each patient, one before the course of radiotherapy treatment and one at the end (approximately 6 weeks later). Separate models were built for each dataset. All models could accurately predict the respiratory motion in the same dataset, but had large errors when predicting the motion in the other dataset. Analysis of the inter-fraction variations revealed that most variations were spatially varying base-line shifts, but changes to the anatomy and the motion trajectories were also observed.

Muscles and their myokines.

Science.gov (United States)

Pedersen, Bente Klarlund

2011-01-15

In the past, the role of physical activity as a life-style modulating factor has been considered as that of a tool to balance energy intake. Although it is important to avoid obesity, physical inactivity should be discussed in a much broader context. There is accumulating epidemiological evidence that a physically active life plays an independent role in the protection against type 2 diabetes, cardiovascular diseases, cancer, dementia and even depression. For most of the last century, researchers sought a link between muscle contraction and humoral changes in the form of an 'exercise factor', which could be released from skeletal muscle during contraction and mediate some of the exercise-induced metabolic changes in other organs such as the liver and the adipose tissue. We have suggested that cytokines or other peptides that are produced, expressed and released by muscle fibres and exert autocrine, paracrine or endocrine effects should be classified as 'myokines'. Given that skeletal muscle is the largest organ in the human body, our discovery that contracting skeletal muscle secretes proteins sets a novel paradigm: skeletal muscle is an endocrine organ producing and releasing myokines, which work in a hormone-like fashion, exerting specific endocrine effects on other organs. Other myokines work via paracrine mechanisms, exerting local effects on signalling pathways involved in muscle metabolism. It has been suggested that myokines may contribute to exercise-induced protection against several chronic diseases.

Respiratory acidosis

Science.gov (United States)

Ventilatory failure; Respiratory failure; Acidosis - respiratory ... Causes of respiratory acidosis include: Diseases of the airways (such as asthma and COPD ) Diseases of the lung tissue (such as ...

Physical inactivity and muscle oxidative capacity in humans

DEFF Research Database (Denmark)

Gram, Martin; Dahl, Rannvá; Dela, Flemming

2014-01-01

Physical inactivity is associated with a high prevalence of type 2 diabetes and is an independent predictor of mortality. It is possible that the detrimental effects of physical inactivity are mediated through a lack of adequate muscle oxidative capacity. This short review will cover the present...... literature on the effects of different models of inactivity on muscle oxidative capacity in humans. Effects of physical inactivity include decreased mitochondrial content, decreased activity of oxidative enzymes, changes in markers of oxidative stress and a decreased expression of genes and contents...... of proteins related to oxidative phosphorylation. With such a substantial down-regulation, it is likely that a range of adenosine triphosphate (ATP)-dependent pathways such as calcium signalling, respiratory capacity and apoptosis are affected by physical inactivity. However, this has not been investigated...

Sugammadex use in difficult intubation due to ankylosing spondylitis and severe restrictive respiratory disease

Directory of Open Access Journals (Sweden)

Yakup Tomak

2012-09-01

Full Text Available We describe anesthesia management of a 50-year-old man scheduled for thoracic spinal reconstruction, presenting with severe restrictive respiratory disease and difficult airway due to ankylosing spondilitis. The patient was unable to extend his head, had difficulty in breathing and sleeping in supine position due to thoracal deformities. The patient was intubated using intubating laryngeal mask airway to overcome the difficulties of limited mouth opening and head extension. He was extubated following administration of sugammadex to obtain optimal conditions in terms of respiratory muscle function and to prevent hypersecretion and bronchospasm. J Clin Exp Invest 2012; 3 (3: 398-400Key words: Restrictive lung disease, airway management, laryngeal masks, sugammadex, ankylosing spondylitis

Respiratory Manifestations of Hypothyroidism: A Systematic Review.

Science.gov (United States)

Sorensen, Jesper Roed; Winther, Kristian Hillert; Bonnema, Steen Joop; Godballe, Christian; Hegedüs, Laszlo

2016-11-01

Hypothyroidism has been associated with increased pulmonary morbidity and overall mortality. A systematic review was conducted to identify the prevalence and underlying mechanisms of respiratory problems among patients with thyroid insufficiency. PubMed and EMBASE databases were searched for relevant literature from January 1950 through January 2015 with the following study eligibility criteria: English-language publications; adult subclinical or overt hypothyroid patients; intervention, observational, or retrospective studies; and respiratory manifestations. The Preferred Reporting Items for Systematic reviews and Meta-Analyses statement was followed, and Cochrane's risk of bias tool was used. A total of 1699 papers were screened by two independent authors for relevant titles. Of 109 relevant abstracts, 28 papers underwent full-text analyses, of which 22 were included in the review. Possible mechanisms explaining respiratory problems at multiple physiological levels were identified, such as the ventilator control system, diaphragmatic muscle function, pulmonary gas exchange, goiter caused upper airway obstruction, decreased capacity for energy transduction, and reduced glycolytic activity. Obstructive sleep apnea syndrome was found among 30% of newly diagnosed patients with overt hypothyroidism, and demonstrated reversibility following treatment. The evidence for or against a direct effect on pulmonary function was ambiguous. However, each of the above-mentioned areas was only dealt with in a limited number of studies. Therefore, it is not possible to draw any strong conclusions on any of these themes. Moreover, most studies were hampered by considerable risk of bias due for example to small numbers of patients, lack of control groups, randomization and blinding, and differences in body mass index, sex, and age between subjects and controls. Mechanistic data linking hypothyroidism and respiratory function are at best limited. This area of research is therefore

Evaluation of Work Fatigue in Loading Workers Using Muscle Fatigue Assessment Method (MFA: A Case Study in a Brick Factory

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Haji Omid Kalte

2016-09-01

Full Text Available Introduction and purpose: Work fatigue is one of the main causes of workrelated musculoskeletal disorders and reduced productivity in industry. Therefore, it is vital to evaluate work fatigue, especially muscle fatigue, to determine the permissible workload. This study aimed to evaluate muscle fatigue of brick field workers. Methods: This cross-sectional study was conducted on transportation sector workers in Pey Dezh Brick Production Company, Golestan, Iran in 2015. In this research, the qualitative of Muscle Fatigue Assessment (MFA method was used to assess the level of fatigue. Duration of each task and frequency of efforts were determined using the level of effort to obtain a numerical result for comparison with the standard level. Results: The evaluated task was to remove paired bricks from the conveyor and transfer them to trailer truck by workers. The final results revealed that lower back tolerated the most amount of pressure (score=323, followed by the shoulders and wrist of the right hand (scores=313, which were assigned to the fatigue level. Therefore, the highest total fatigue of workload was imposed on these body parts. Conclusion: According to the results of this study, the upper limbs of workers incurred the highest burden in lifting bricks, and there was a in risk of WMSDS due to high workload. Therefore, it is recommended that working systems be improved through rotating work and reducing the number of transferred bricks to avoid risks caused by accumulation of fatigue.

Increased mitochondrial substrate sensitivity in skeletal muscle of patients with type 2 diabetes

DEFF Research Database (Denmark)

Larsen, S; Stride, N; Hey-Mogensen, Martin

2011-01-01

AIMS/HYPOTHESIS: Mitochondrial respiration has been linked to insulin resistance. We studied mitochondrial respiratory capacity and substrate sensitivity in patients with type 2 diabetes (patients), and obese and lean control participants. METHODS: Mitochondrial respiration was measured.......4). Substrate sensitivity for octanoyl-carnitine did not differ between groups. CONCLUSIONS/INTERPRETATION: Increased mitochondrial substrate sensitivity is seen in skeletal muscle from type 2 diabetic patients and is confined to non-lipid substrates. Respiratory capacity per mitochondrion is not decreased...... and maximal oxygen uptake (VO2) were also determined. Insulin sensitivity was determined with the isoglycaemic-hyperinsulinaemic clamp technique. RESULTS: Insulin sensitivity was different (p

Illness Severity and Work Productivity Loss Among Working Adults With Medically Attended Acute Respiratory Illnesses: US Influenza Vaccine Effectiveness Network 2012-2013.

Science.gov (United States)

Petrie, Joshua G; Cheng, Caroline; Malosh, Ryan E; VanWormer, Jeffrey J; Flannery, Brendan; Zimmerman, Richard K; Gaglani, Manjusha; Jackson, Michael L; King, Jennifer P; Nowalk, Mary Patricia; Benoit, Joyce; Robertson, Anne; Thaker, Swathi N; Monto, Arnold S; Ohmit, Suzanne E

2016-02-15

Influenza causes significant morbidity and mortality, with considerable economic costs, including lost work productivity. Influenza vaccines may reduce the economic burden through primary prevention of influenza and reduction in illness severity. We examined illness severity and work productivity loss among working adults with medically attended acute respiratory illnesses and compared outcomes for subjects with and without laboratory-confirmed influenza and by influenza vaccination status among subjects with influenza during the 2012-2013 influenza season. Illnesses laboratory-confirmed as influenza (ie, cases) were subjectively assessed as more severe than illnesses not caused by influenza (ie, noncases) based on multiple measures, including current health status at study enrollment (≤7 days from illness onset) and current activity and sleep quality status relative to usual. Influenza cases reported missing 45% more work hours (20.5 vs 15.0; P productivity as impeded to a greater degree (6.0 vs 5.4; P productivity loss were noted for vaccinated subjects. Influenza illnesses were more severe and resulted in more missed work hours and productivity loss than illnesses not confirmed as influenza. Modest reductions in illness severity for vaccinated cases were observed. These findings highlight the burden of influenza illnesses and illustrate the importance of laboratory confirmation of influenza outcomes in evaluations of vaccine effectiveness. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Mitochondrial respiration is decreased in skeletal muscle of patients with type 2 diabetes

DEFF Research Database (Denmark)

Hey-Mogensen, Martin; Sahlin, Kent; Fernström, Maria

2007-01-01

, and the proportion of type 2X fibers correlated with markers of insulin resistance (P type 2X fibers in muscle of type 2 diabetic patients. These alterations may contribute to the development......We tested the hypothesis of a lower respiratory capacity per mitochondrion in skeletal muscle of type 2 diabetic patients compared with obese subjects. Muscle biopsies obtained from 10 obese type 2 diabetic and 8 obese nondiabetic male subjects were used for assessment of 3-hydroxy....... Maximal ADP-stimulated respiration (state 3) with pyruvate plus malate and respiration through the electron transport chain (ETC) were reduced in type 2 diabetic patients, and the proportion of type 2X fibers were higher in type 2 diabetic patients compared with obese subjects (all P

Regulatory mechanisms of skeletal muscle protein turnover during exercise

DEFF Research Database (Denmark)

Rose, Adam John; Richter, Erik

2009-01-01

Skeletal muscle protein turnover is a relatively slow metabolic process that is altered by various physiological stimuli such as feeding/fasting and exercise. During exercise, catabolism of amino acids contributes very little to ATP turnover in working muscle. With regards to protein turnover......, there is now consistent data from tracer studies in rodents and humans showing that global protein synthesis is blunted in working skeletal muscle. Whether there is altered skeletal muscle protein breakdown during exercise remains unclear. The blunting of protein synthesis is believed to be mediated...... downstream of changes in intracellular Ca(2+) and energy turnover. In particular, a signaling cascade involving Ca(2+)-calmodulin-eEF2 kinase-eEF2 is implicated. The possible functional significance of altered protein turnover in working skeletal muscle during exercise is discussed. Further work...

Muscle mitochondrial metabolism and calcium signaling impairment in patients treated with statins

Energy Technology Data Exchange (ETDEWEB)

Sirvent, P., E-mail: pascal.sirvent@univ-bpclermont.fr [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France); Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l' Exercice en conditions Physiologiques et Pathologiques (AME2P), BP 80026, F-63171 Aubière cedex (France); Fabre, O.; Bordenave, S. [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France); Hillaire-Buys, D. [CHRU Montpellier, 34295 Montpellier (France); Raynaud De Mauverger, E.; Lacampagne, A.; Mercier, J. [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France)

2012-03-01

The most common and problematic side effect of statins is myopathy. To date, the patho-physiological mechanisms of statin myotoxicity are still not clearly understood. In previous studies, we showed that acute application in vitro of simvastatin caused impairment of mitochondrial function and dysfunction of calcium homeostasis in human and rat healthy muscle samples. We thus evaluated in the present study, mitochondrial function and calcium signaling in muscles of patients treated with statins, who present or not muscle symptoms, by oxygraphy and recording of calcium sparks, respectively. Patients treated with statins showed impairment of mitochondrial respiration that involved mainly the complex I of the respiratory chain and altered frequency and amplitude of calcium sparks. The muscle problems observed in statin-treated patients appear thus to be related to impairment of mitochondrial function and muscle calcium homeostasis, confirming the results we previously reported in vitro. -- Highlights: ► The most common and problematic side effect of statins is myopathy. ► Patients treated with statins showed impairment of mitochondrial respiration. ► Statins-treated patients showed altered frequency and amplitude of calcium sparks.

Muscle mitochondrial metabolism and calcium signaling impairment in patients treated with statins

International Nuclear Information System (INIS)

Sirvent, P.; Fabre, O.; Bordenave, S.; Hillaire-Buys, D.; Raynaud De Mauverger, E.; Lacampagne, A.; Mercier, J.

2012-01-01

The most common and problematic side effect of statins is myopathy. To date, the patho-physiological mechanisms of statin myotoxicity are still not clearly understood. In previous studies, we showed that acute application in vitro of simvastatin caused impairment of mitochondrial function and dysfunction of calcium homeostasis in human and rat healthy muscle samples. We thus evaluated in the present study, mitochondrial function and calcium signaling in muscles of patients treated with statins, who present or not muscle symptoms, by oxygraphy and recording of calcium sparks, respectively. Patients treated with statins showed impairment of mitochondrial respiration that involved mainly the complex I of the respiratory chain and altered frequency and amplitude of calcium sparks. The muscle problems observed in statin-treated patients appear thus to be related to impairment of mitochondrial function and muscle calcium homeostasis, confirming the results we previously reported in vitro. -- Highlights: ► The most common and problematic side effect of statins is myopathy. ► Patients treated with statins showed impairment of mitochondrial respiration. ► Statins-treated patients showed altered frequency and amplitude of calcium sparks.

The Angiotensin Converting Enzyme Insertion/Deletion Polymorphism Modifies Exercise-Induced Muscle Metabolism.

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David Vaughan

Full Text Available A silencer region (I-allele within intron 16 of the gene for the regulator of vascular perfusion, angiotensin-converting enzyme (ACE, is implicated in phenotypic variation of aerobic fitness and the development of type II diabetes. We hypothesised that the reportedly lower aerobic performance in non-carriers compared to carriers of the ACE I-allele, i.e. ACE-DD vs. ACE-ID/ACE-II genotype, is associated with alterations in activity-induced glucose metabolism and capillarisation in exercise muscle.Fifty-three, not-specifically trained Caucasian men carried out a one-legged bout of cycling exercise to exhaustion and/or participated in a marathon, the aim being to identify and validate genotype effects on exercise metabolism. Respiratory exchange ratio (RER, serum glucose and lipid concentration, glycogen, and metabolite content in vastus lateralis muscle based on ultra-performance lipid chromatography-mass spectrometry (UPLC-MS, were assessed before and after the cycling exercise in thirty-three participants. Serum metabolites were measured in forty subjects that completed the marathon. Genotype effects were assessed post-hoc.Cycling exercise reduced muscle glycogen concentration and this tended to be affected by the ACE I-allele (p = 0.09. The ACE-DD genotype showed a lower maximal RER and a selective increase in serum glucose concentration after exercise compared to ACE-ID and ACE-II genotypes (+24% vs. +2% and -3%, respectively. Major metabolites of mitochondrial metabolism (i.e. phosphoenol pyruvate, nicotinamide adenine dinucleotide phosphate, L-Aspartic acid, glutathione were selectively affected in vastus lateralis muscle by exercise in the ACE-DD genotype. Capillary-to-fibre ratio was 24%-lower in the ACE-DD genotype. Individuals with the ACE-DD genotype demonstrated an abnormal increase in serum glucose to 7.7 mM after the marathon.The observations imply a genetically modulated role for ACE in control of glucose import and oxidation in

Respiratory risks in broiler production workers

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M do CB de Alencar

2004-03-01

Full Text Available There are many situations that involve health risks to the Brazilian rural worker, and animal production is just one of them. Inhalation of organic dust, which has many microorganisms, leads in general to respiratory allergic reactions in some individuals, "asthma-like syndrome", and mucous membrane inflammation syndrome, that is a complex of nasal, eye, and throat complaints. Furthermore, workers might have farmer's hypersensitivity pneumonia, that is a respiratory health risk along the years. The objective of this study was to evaluate the potential pulmonary health risks in poultry production workers in the region of Curitiba, PR, Brazil. Interviews using a pre-elaborated questionnaire with 40 questions were made with 37 broiler production workers, which were submitted to a pulmonary function test. Results of restrictive function with lower FEV1 (the maximum respiratory potential, the forced expiratory volume in the first second of exhalation and FVC (forced vital capacity represented 24.32% of the total of workers, and severe obstruction represented 2.70%. Other symptoms were found in 67.57% of the workers as well. The results showed that those who work more than 4 years and within more than one poultry house, exceeding 5 hours per day of work, presented higher pulmonary health risks. It is concluded that the activities within broiler houses may induce allergic respiratory reaction in workers. The use of IPE (individual protection equipment besides special attention to the air quality inside the housing may be advised in a preventive way.

Respiratory alkalosis

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Alkalosis - respiratory ... leads to shortness of breath can also cause respiratory alkalosis (such as pulmonary embolism and asthma). ... Treatment is aimed at the condition that causes respiratory alkalosis. Breathing into a paper bag -- or using ...

Metallic Muscles at Work : High Rate Actuation in Nanoporous Gold/Polyaniline Composites

NARCIS (Netherlands)

Detsi, Eric; Onck, Patrick; De Hosson, Jeff Th. M.

Metallic muscles made of nanoporous metals suffer from serious drawbacks caused by the usage of an aqueous electrolyte for actuation. An aqueous electrolyte prohibits metallic muscles from operating in dry environments and hampers a high actuation rate due to the low ionic conductivity of

Nasally administered Lactobacillus rhamnosus strains differentially modulate respiratory antiviral immune responses and induce protection against respiratory syncytial virus infection.

Science.gov (United States)

Tomosada, Yohsuke; Chiba, Eriko; Zelaya, Hortensia; Takahashi, Takuya; Tsukida, Kohichiro; Kitazawa, Haruki; Alvarez, Susana; Villena, Julio

2013-08-15

Some studies have shown that nasally administered immunobiotics had the potential to improve the outcome of influenza virus infection. However, the capacity of immunobiotics to improve protection against respiratory syncytial virus (RSV) infection was not investigated before. The aims of this study were: a) to evaluate whether the nasal administration of Lactobacillus rhamnosus CRL1505 (Lr05) and L. rhamnosus CRL1506 (Lr06) are able to improve respiratory antiviral defenses and beneficially modulate the immune response triggered by TLR3/RIG-I activation; b) to investigate whether viability of Lr05 or Lr06 is indispensable to modulate respiratory immunity and; c) to evaluate the capacity of Lr05 and Lr06 to improve the resistance of infant mice against RSV infection. Nasally administered Lr05 and Lr06 differentially modulated the TLR3/RIG-I-triggered antiviral respiratory immune response. Lr06 administration significantly modulated the production of IFN-α, IFN-β and IL-6 in the response to poly(I:C) challenge, while nasal priming with Lr05 was more effective to improve levels of IFN-γ and IL-10. Both viable Lr05 and Lr06 strains increased the resistance of infant mice to RSV infection while only heat-killed Lr05 showed a protective effect similar to those observed with viable strains. The present work demonstrated that nasal administration of immunobiotics is able to beneficially modulate the immune response triggered by TLR3/RIG-I activation in the respiratory tract and to increase the resistance of mice to the challenge with RSV. Comparative studies using two Lactobacillus rhamnosus strains of the same origin and with similar technological properties showed that each strain has an specific immunoregulatory effect in the respiratory tract and that they differentially modulate the immune response after poly(I:C) or RSV challenges, conferring different degree of protection and using distinct immune mechanisms. We also demonstrated in this work that it is possible

Comparison of Mitochondrial Reactive Oxygen Species Production of Ectothermic and Endothermic Fish Muscle

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Lilian Wiens

2017-09-01

Full Text Available Recently we demonstrated that the capacity of isolated muscle mitochondria to produce reactive oxygen species, measured as H2O2 efflux, is temperature-sensitive in isolated muscle mitochondria of ectothermic fish and the rat, a representative endothermic mammal. However, at physiological temperatures (15° and 37°C for the fish and rat, respectively, the fraction of total mitochondrial electron flux that generated H2O2, the fractional electron leak (FEL, was far lower in the rat than in fish. Those results suggested that the elevated body temperatures associated with endothermy may lead to a compensatory decrease in mitochondrial ROS production relative to respiratory capacity. To test this hypothesis we compare slow twitch (red muscle mitochondria from the endothermic Pacific bluefin tuna (Thunnus orientalis with mitochondria from three ectothermic fishes [rainbow trout (Oncorhynchus mykiss, common carp (Cyprinus carpio, and the lake sturgeon (Acipenser fulvescens] and the rat. At a common assay temperature (25°C rates of mitochondrial respiration and H2O2 efflux were similar in tuna and the other fishes. The thermal sensitivity of fish mitochondria was similar irrespective of ectothermy or endothermy. Comparing tuna to the rat at a common temperature, respiration rates were similar, or lower depending on mitochondrial substrates. FEL was not different across fish species at a common assay temperature (25°C but was markedly higher in fishes than in rat. Overall, endothermy and warming of Pacific Bluefin tuna red muscle may increase the potential for ROS production by muscle mitochondria but the evolution of endothermy in this species is not necessarily associated with a compensatory reduction of ROS production relative to the respiratory capacity of mitochondria.

GH and cortisol responses following an acute session of respiratory muscle endurance training in severely obese patients.

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Sartorio, A; Agosti, F; Patrizi, A; Gattico, A; Tringali, G; Giunta, M; Muller, E E; Rigamonti, A E

2013-03-01

It is well established that obese patients are hypo-responsive to classical GH-releasing stimuli, including aerobic exercise. Recently, we have demonstrated that whole body vibration was able to markedly stimulate GH secretion in obese patients, thus suggesting that this refractoriness is not absolute but dependent on the GH-releasing stimulus. Furthermore, we have shown the ability of a respiratory muscle endurance training (RMET) to stimulate GH and cortisol secretion in healthy subjects. The objective of this study was to evaluate the effects of RMET on GH and cortisol responses in severely obese patients. Eight severely obese patients (4 M/4 F, mean age±SEM: 22.8±1.6 years, body mass index, BMI: 39.9±1.1 kg/m2) underwent an incremental progressive RMET protocol of 11 daily sessions, obtained through the use of a specifically designed respiratory device (Spiro Tiger®). The 12th session of RMET (15 min duration: 1 min at a respiration rate of 28 acts/min, 5 min at 32 acts/min, 5 min at 34 acts/min, 4 min at 36 acts/min) was associated with blood samplings for determination of GH, cortisol, and lactate (LA) levels. An age- and sex-matched normal-weighted control group (n=7, 4 M/3 F, age: 26.1±3.1 years, BMI: 22.4±0.6 kg/m2) was also recruited. In both normal-weighted subjects and obese patients, GH secretion significantly increased after a 15-min RMET session. Although serum GH levels at 30 min were higher in normal-weighted subjects than in obese patients, there was no statistically significant difference in either GH peaks or net GH areas under the curve between the 2 groups. RMET significantly increased serum cortisol levels in normal-weighted subjects, but was associated to a progressive cortisol decline in obese patients. RMET stimulated LA production, with no significant differences in normal-weighted subjects and in obese patients. A 15-min RMET session was capable to induce a GH response in severely obese patients, which was comparable to that

Electrical stimulation for physiologic measurement of neuromuscular function and respiratory support during anticholinesterase poisoning. Annual report, October 1983-September 1984

Energy Technology Data Exchange (ETDEWEB)

Yodlowski, E.H.

1984-10-01

The purpose of this research is to develop the techniques necessary for providing short-term respiratory support for personnel poisoned by organophosphate agents. Following acute exposure to organophosphate compounds, respiration ceases before cardiovascular collapse occurs. Military personnel exposed to these compounds in the field are most likely to die from asphyxiation. By virtue of their ability to cross the blood-brain barrier and inhibit cholinesterase activity the organophosphates are capable of interrupting control of respiration either centrally (i.e. within the central nervous system) or peripherally by blocking neuromuscular transmission or contraction coupling at the peripheral muscles. We hypothesize that it will be possible to overcome organophosphate induced respiratory arrest by providing artificial respiratory pacing. This research is aimed at producing a means of respiratory support via electronic stimulation of the phrenic nerve (s) that can be used when central respiratory drive has become blocked by organophosphate agents. Animal experiments have been conducted to implement and evaluate the transesophageal electrophrenic stimulation technique (TEST) for respiratory pacing and to determine appropriate stimulation parameters to produce effective and efficient respirations.

Pelvic floor muscle training for female urinary incontinence: Does it work?

Science.gov (United States)

Singh, Nilanjana; Rashid, Mumtaz; Bayliss, Lorna; Graham, Penny

2016-06-01

Supervised pelvic floor muscle training in patients of stress and mixed urinary incontinence has been recommended. Our aim was to assess the utilisation and effectiveness of our supervised pelvic floor muscle training service and assess the impact of incontinence scores before physiotherapy on the subsequent results of physiotherapy. All 271 patients referred to physiotherapy for symptoms of incontinence filled out the International Consultation on Incontinence Modular Questionnaire-Female Lower Urinary Tract Symptoms before starting treatment. Depending on pelvic floor muscle assessment, plans for exercises and follow up were made. If the strength of pelvic floor muscles was poor, electrical stimulation was offered. If awareness of the pelvic floor muscle contraction was poor, bio feedback was offered. Group sessions and vaginal cones were also used. Depending on the response to the treatment; patients were either discharged, referred to Urogynaecology clinic or continued physiotherapy. All patients who were discharged or referred for surgery were given a post treatment questionnaire to fill out. 79 (56 %) of 132 women with stress, 49 (51 %) of 98 with mixed and 27 (66 %) of 41 with urge incontinence reported successful control of symptoms (overall success 54 %). However, 65 % of women with incontinence scores of 0-5 before physiotherapy, 64 % with 6-10, 42 % with 11-15 and mere 28 % with 16-20 achieved success with physiotherapy. 27 (10 %) were lost to follow up. 1 in 2 women referred to physiotherapy for incontinence, achieved successful control of symptoms without the need for invasive investigations or surgery. However, poor incontinence scores before the start of physiotherapy is a poor prognostic indicator for success. 90 % women utilised the service.

A new mitochondrial point mutation in the transfer RNA(Lys) gene associated with progressive external ophthalmoplegia with impaired respiratory regulation.

Science.gov (United States)

Wolf, Joachim; Obermaier-Kusser, Bert; Jacobs, Martina; Milles, Cornelia; Mörl, Mario; von Pein, Harald D; Grau, Armin J; Bauer, Matthias F

2012-05-15

We report a novel heteroplasmic point mutation G8299A in the gene for mitochondrial tRNA(Lys) in a patient with progressive external ophthalmoplegia complicated by recurrent respiratory insufficiency. Biochemical analysis of respiratory chain complexes in muscle homogenate showed a combined complex I and IV deficiency. The transition does not represent a known neutral polymorphism and affects a position in the tRNA acceptor stem which is conserved in primates, leading to a destabilization of this functionally important domain. In vitro analysis of an essential maturation step of the tRNA transcript indicates the probable pathogenicity of this mutation. We hypothesize that there is a causal relationship between the novel G8299A transition and progressive external ophthalmoplegia with recurrent respiratory failure due to a depressed respiratory drive. Copyright © 2012 Elsevier B.V. All rights reserved.

The effects of a passive exoskeleton on muscle activity, discomfort and endurance time in forward bending work.

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Bosch, Tim; van Eck, Jennifer; Knitel, Karlijn; de Looze, Michiel

2016-05-01

Exoskeletons may form a new strategy to reduce the risk of developing low back pain in stressful jobs. In the present study we examined the potential of a so-called passive exoskeleton on muscle activity, discomfort and endurance time in prolonged forward-bended working postures. Eighteen subjects performed two tasks: a simulated assembly task with the trunk in a forward-bended position and static holding of the same trunk position without further activity. We measured the electromyography for muscles in the back, abdomen and legs. We also measured the perceived local discomfort. In the static holding task we determined the endurance, defined as the time that people could continue without passing a specified discomfort threshold. In the assembly task we found lower muscle activity (by 35-38%) and lower discomfort in the low back when wearing the exoskeleton. Additionally, the hip extensor activity was reduced. The exoskeleton led to more discomfort in the chest region. In the task of static holding, we observed that exoskeleton use led to an increase in endurance time from 3.2 to 9.7 min, on average. The results illustrate the good potential of this passive exoskeleton to reduce the internal muscle forces and (reactive) spinal forces in the lumbar region. However, the adoption of an over-extended knee position might be, among others, one of the concerns when using the exoskeleton. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Respiratory symptoms in insect breeders.

Science.gov (United States)

Harris-Roberts, J; Fishwick, D; Tate, P; Rawbone, R; Stagg, S; Barber, C M; Adisesh, A

2011-08-01

A number of specialist food suppliers in the UK breed and distribute insects and insect larvae as food for exotic pets, such as reptiles, amphibians and invertebrates. To investigate the extent of work-related (WR) symptoms and workplace-specific serum IgE in workers potentially exposed to a variety of biological contaminants, including insect and insect larvae allergens, endotoxin and cereal allergens at a UK specialist insect breeding facility. We undertook a study of respiratory symptoms and exposures at the facility, with subsequent detailed clinical assessment of one worker. All 32 workers were assessed clinically using a respiratory questionnaire and lung function. Eighteen workers consented to provide serum for determination of specific IgE to workplace allergens. Thirty-four per cent (11/32) of insect workers reported WR respiratory symptoms. Sensitization, as judged by specific IgE, was found in 29% (4/14) of currently exposed workers. Total inhalable dust levels ranged from 1.2 to 17.9 mg/m(3) [mean 4.3 mg/m(3) (SD 4.4 mg/m(3)), median 2.0 mg/m(3)] and endotoxin levels of up to 29435 EU/m(3) were recorded. Exposure to organic dusts below the levels for which there are UK workplace exposure limits can result in respiratory symptoms and sensitization. The results should alert those responsible for the health of similarly exposed workers to the potential for respiratory ill-health and the need to provide a suitable health surveillance programme.

Motor unit recruitment in human genioglossus muscle in response to hypercapnia.

Science.gov (United States)

Nicholas, Christian L; Bei, Bei; Worsnop, Christopher; Malhotra, Atul; Jordan, Amy S; Saboisky, Julian P; Chan, Julia K M; Duckworth, Ella; White, David P; Trinder, John

2010-11-01

single motor unit recordings of the genioglossus (GG) muscle indicate that GG motor units have a variety of discharge patterns, including units that have higher discharge rates during inspiration (inspiratory phasic and inspiratory tonic), or expiration (expiratory phasic and expiratory tonic), or do not modify their rate with respiration (tonic). Previous studies have shown that an increase in GG muscle activity is a consequence of increased activity in inspiratory units. However, there are differences between studies as to whether this increase is primarily due to recruitment of new motor units (motor unit recruitment) or to increased discharge rate of already active units (rate coding). Sleep-wake state studies in humans have suggested the former, while hypercapnia experiments in rats have suggested the latter. In this study, we investigated the effect of hypercapnia on GG motor unit activity in humans during wakefulness. sleep research laboratory. sixteen healthy men. each participant was administered at least 6 trials with P(et)CO(2) being elevated 8.4 (SD = 1.96) mm Hg over 2 min following a 30-s baseline. Subjects were instrumented for GG EMG and respiratory measurements with 4 fine wire electrodes inserted subcutaneously into the muscle. One hundred forty-one motor units were identified during the baseline: 47% were inspiratory modulated, 29% expiratory modulated, and 24% showed no respiratory related modulation. Sixty-two new units were recruited during hypercapnia. The distribution of recruited units was significantly different from the baseline distribution, with 84% being inspiratory modulated (P units active during baseline, nor new units recruited during hypercapnia, increased their discharge rate as P(et)CO(2) increased (P > 0.05 for all comparisons). increased GG muscle activity in humans occurs because of recruitment of previously inactive inspiratory modulated units.

Mitochondrial dysfunction in human skeletal muscle biopsies of lipid storage disorder.

Science.gov (United States)

Debashree, Bandopadhyay; Kumar, Manish; Keshava Prasad, Thottethodi Subrahmanya; Natarajan, Archana; Christopher, Rita; Nalini, Atchayaram; Bindu, Parayil Sankaran; Gayathri, Narayanappa; Srinivas Bharath, Muchukunte Mukunda

2018-02-09

Mitochondria regulate the balance between lipid metabolism and storage in the skeletal muscle. Altered lipid transport, metabolism and storage influence the bioenergetics, redox status and insulin signalling, contributing to cardiac and neurological diseases. Lipid storage disorders (LSDs) are neurological disorders which entail intramuscular lipid accumulation and impaired mitochondrial bioenergetics in the skeletal muscle causing progressive myopathy with muscle weakness. However, the mitochondrial changes including molecular events associated with impaired lipid storage have not been completely understood in the human skeletal muscle. We carried out morphological and biochemical analysis of mitochondrial function in muscle biopsies of human subjects with LSDs (n = 7), compared to controls (n = 10). Routine histology, enzyme histochemistry and ultrastructural analysis indicated altered muscle cell morphology and mitochondrial structure. Protein profiling of the muscle mitochondria from LSD samples (n = 5) (vs. control, n = 5) by high-throughput mass spectrometric analysis revealed that impaired metabolic processes could contribute to mitochondrial dysfunction and ensuing myopathy in LSDs. We propose that impaired fatty acid and respiratory metabolism along with increased membrane permeability, elevated lipolysis and altered cristae entail mitochondrial dysfunction in LSDs. Some of these mechanisms were unique to LSD apart from others that were common to dystrophic and inflammatory muscle pathologies. Many differentially regulated mitochondrial proteins in LSD are linked with other human diseases, indicating that mitochondrial protection via targeted drugs could be a treatment modality in LSD and related metabolic diseases. © 2018 International Society for Neurochemistry.

Insulin resistance and mitochondrial function in skeletal muscle

DEFF Research Database (Denmark)

Dela, Flemming; Helge, Jørn Wulff

2013-01-01

are used in the attempt to resolve the mechanisms of insulin resistance. In this context, a dysfunction of mitochondria in the skeletal muscle has been suggested to play a pivotal role. It has been postulated that a decrease in the content of mitochondria in the skeletal muscle can explain the insulin...... resistance. Complementary to this also specific defects of components in the respiratory chain in the mitochondria have been suggested to play a role in insulin resistance. A key element in these mechanistic suggestions is inability to handle substrate fluxes and subsequently an accumulation of ectopic...... intramyocellular lipids, interfering with insulin signaling. In this review we will present the prevailing view-points and argue for the unlikelihood of this scenario being instrumental in human insulin resistance. This article is part of a Directed Issue entitled: Bioenergetic dysfunction....

Diaphragm Muscle Weakness Following Acute Sustained Hypoxic Stress in the Mouse Is Prevented by Pretreatment with N-Acetyl Cysteine

Directory of Open Access Journals (Sweden)

Andrew J. O’Leary

2018-01-01

Full Text Available Oxygen deficit (hypoxia is a major feature of cardiorespiratory diseases characterized by diaphragm dysfunction, yet the putative role of hypoxic stress as a driver of diaphragm dysfunction is understudied. We explored the cellular and functional consequences of sustained hypoxic stress in a mouse model. Adult male mice were exposed to 8 hours of normoxia, or hypoxia (FiO2 = 0.10 with or without antioxidant pretreatment (N-acetyl cysteine, 200 mg/kg i.p.. Ventilation and metabolism were measured. Diaphragm muscle contractile function, myofibre size and distribution, gene expression, protein signalling cascades, and oxidative stress (TBARS were determined. Hypoxia caused pronounced diaphragm muscle weakness, unrelated to increased respiratory muscle work. Hypoxia increased diaphragm HIF-1α protein content and activated MAPK, mTOR, Akt, and FoxO3a signalling pathways, largely favouring protein synthesis. Hypoxia increased diaphragm lipid peroxidation, indicative of oxidative stress. FoxO3 and MuRF-1 gene expression were increased. Diaphragm 20S proteasome activity and muscle fibre size and distribution were unaffected by acute hypoxia. Pretreatment with N-acetyl cysteine substantially enhanced cell survival signalling, prevented hypoxia-induced diaphragm oxidative stress, and prevented hypoxia-induced diaphragm dysfunction. Hypoxia is a potent driver of diaphragm weakness, causing myofibre dysfunction without attendant atrophy. N-acetyl cysteine protects the hypoxic diaphragm and may have application as a potential adjunctive therapy.

Perturbations of NAD+ salvage systems impact mitochondrial function and energy homeostasis in mouse myoblasts and intact skeletal muscle

DEFF Research Database (Denmark)

Andersen, Marianne Agerholm; Dall, Morten; Jensen, Benjamin Anderschou Holbech

2018-01-01

Nicotinamide adenine dinucleotide (NAD+) can be synthesized by nicotinamide phosphoribosyltransferase (NAMPT). We aimed to determine the role of NAMPT for maintaining NAD+ levels, mitochondrial function, and metabolic homeostasis in skeletal muscle cells. We generated stable Nampt knockdown (sh......Nampt KD) C2C12 cells using a shRNA lentiviral approach. Moreover, we applied gene electrotransfer to express cre recombinase in tibialis anterior muscle of floxed Nampt mice. In shNampt KD C2C12 myoblasts, Nampt and NAD+ levels were reduced by 70% and 50%, respectively, and maximal respiratory capacity...... was reduced by 25%. Moreover, anaerobic glycolytic flux increased by 55% and 2-deoxyglucose uptake increased by 25% in shNampt KD cells. Treatment with the NAD+ precursor nicotinamide riboside restored NAD+ levels in shNampt cells and increased maximal respiratory capacity by 18% and 32% in control and sh...

Maternal high fat diet alters skeletal muscle mitochondrial catalytic activity in adult male rat offspring.

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Chantal Anne Pileggi

2016-11-01

Full Text Available A maternal high-fat (HF diet during pregnancy can lead to metabolic compromise such as insulin resistance in adult offspring. Skeletal muscle mitochondrial dysfunction is one mechanism contributing to metabolic impairments in insulin resistant states. Therefore, the present study aimed to investigate whether mitochondrial dysfunction is evident in metabolically compromised offspring born to HF-fed dams. Sprague-Dawley dams were randomly assigned to receive a purified control diet (CD; 10% kcal from fat or a high fat diet (HFD; 45% kcal from fat for 10 days prior to mating, throughout pregnancy and during lactation. From weaning, all male offspring received a standard chow diet and soleus muscle was collected at day 150. Expression of the mitochondrial transcription factors nuclear respiratory factor-1 (NRF1 and mitochondrial transcription factor A (mtTFA were downregulated in HF offspring. Furthermore, genes encoding the mitochondrial electron transport system (ETS respiratory complex subunits were supressed in HF offspring. Moreover, protein expression of the complex I subunit, NDUFB8, was downregulated in HF offspring (36%, which was paralleled by decreased maximal catalytic linked activity of complex I and III (40%. Together, these results indicate that exposure to a maternal HF diet during development may elicit lifelong mitochondrial alterations in offspring skeletal muscle.

Respiratory

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The words "respiratory" and "respiration" refer to the lungs and breathing. ... Boron WF. Organization of the respiratory system. In: Boron WF, Boulpaep EL, eds. Medical Physiology . 3rd ed. Philadelphia, PA: Elsevier; 2017:chap 26.

Respiratory symptoms and functions in barn workers

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Ege Gulec Balbay

2014-03-01

Full Text Available Introduction and aim. The presented study was undertaken to investigate the respiratory health problems in family barns with one or more cows and at least one family member working in the barn. Methods. 150 workers (128 female, 22 male from 4 villages of Yığılca district near the city of Düzce in north-west Turkey were enrolled in this study between October – December 2011. An Occupational and Environmental Chest Diseases questionnaire developed by the American Thoracic Society, pulmonary function test, physical examination and investigation for nasal eosinophil were performed in all subjects. Results. The mean age of workers was 47.7 ± 14.2 years. Cough was present in 24% of subjects. The rates of phlegm, wheezing, chest tightness and dyspnea were 13.3%, 6%, 6% and 27.3%, respectively. Obstructive ventilatory pattern was observed in 37 workers (24.6%. 43 workers (28.6% showed restrictive ventilatory pattern. Nasal eosinophilia was detected in 47.3% (71/150 of the subjects. Pulmonary functions of workers with nasal eosinophilia did not differ from the other workers. There were statistically significant negative correlations between the duration of working in barns and respiratory functions. Conclusions. Pulmonary functions of barn workers have been found to be decreased related to the duration of barn working. Furthermore, respiratory symptoms increased in relation with both barn working and biomass consumption. Precautions should therefore be taken to ventilate both barns and houses.

The respiratory microbiome and respiratory infections

NARCIS (Netherlands)

Unger, Stefan A.; Bogaert, Debby

2017-01-01

Despite advances over the past ten years lower respiratory tract infections still comprise around a fifth of all deaths worldwide in children under five years of age with the majority in low- and middle-income countries. Known risk factors for severe respiratory infections and poor chronic

Respiratory Disorders Among Workers in Slaughterhouses

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Abbasali Kasaeinasab

2017-03-01

Conclusion: The prevalence of respiratory disorders was significantly higher among workers in slaughterhouses. Thus, the significant reduction in the percentage predicted lung function among workers in slaughterhouses might be associated with exposure to bioaerosols in their work environment.

Zebrafish: a model animal for analyzing the impact of environmental pollutants on muscle and brain mitochondrial bioenergetics.

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Bourdineaud, Jean-Paul; Rossignol, R; Brèthes, D

2013-01-01

Mercury, anthropogenic release of uranium (U), and nanoparticles constitute hazardous environmental pollutants able to accumulate along the aquatic food chain with severe risk for animal and human health. The impact of such pollutants on living organisms has been up to now approached by classical toxicology in which huge doses of toxic compounds, environmentally irrelevant, are displayed through routes that never occur in the lifespan of organisms (for instance injecting a bolus of mercury to an animal although the main route is through prey and fish eating). We wanted to address the effect of such pollutants on the muscle and brain mitochondrial bioenergetics under realistic conditions, at unprecedented low doses, using an aquatic model animal, the zebrafish Danio rerio. We developed an original method to measure brain mitochondrial respiration: a single brain was put in 1.5 mL conical tube containing a respiratory buffer. Brains were gently homogenized by 13 strokes with a conical plastic pestle, and the homogenates were immediately used for respiration measurements. Skinned muscle fibers were prepared by saponin permeabilization. Zebrafish were contaminated with food containing 13 μg of methylmercury (MeHg)/g, an environmentally relevant dose. In permeabilized muscle fibers, we observed a strong inhibition of both state 3 mitochondrial respiration and cytochrome c oxidase activity after 49 days of MeHg exposure. We measured a dramatic decrease in the rate of ATP release by skinned muscle fibers. Contrarily to muscles, brain mitochondrial respiration was not modified by MeHg exposure although brain accumulated twice as much MeHg than muscles. When zebrafish were exposed to 30 μg/L of waterborne U, the basal mitochondrial respiratory control ratio was decreased in muscles after 28 days of exposure. This was due to an increase of the inner mitochondrial membrane permeability. The impact of a daily ration of food containing gold nanoparticles of two sizes (12 and