Sample records for adductor policis muscle

  1. Hip adductor muscle function in forward skating.

    PubMed

    Chang, Ryan; Turcotte, Rene; Pearsall, David

    2009-09-01

    Adductor strain injuries are prevalent in ice hockey. It has long been speculated that adductor muscular strains may be caused by repeated eccentric contractions which decelerate the leg during a stride. The purpose of this study was to investigate the relationship of skating speed with muscle activity and lower limb kinematics, with a particular focus on the role of the hip adductors. Seven collegiate ice hockey players consented to participate. Surface electromyography (EMG) and kinematics of the lower extremities were measured at three skating velocities 3.33 m/s (slow), 5.00 m/s (medium) and 6.66 m/s (fast). The adductor magnus muscle exhibited disproportionately larger increases in peak muscle activation and significantly prolonged activation with increased speed. Stride rate and stride length also increased significantly with skating velocity, in contrast, hip, knee and ankle total ranges of motion did not. To accommodate for the increased stride rate with higher skating speeds, the rate of hip abduction increased significantly in concert with activations of adductor magnus indicating a substantial eccentric contraction. In conclusion, these findings highlight the functional importance of the adductor muscle group and hip abduction-adduction in skating performance as well as indirectly support the notion that groin strain injury potential increases with skating speed.

  2. Isokinetic imbalance of adductor-abductor hip muscles in professional soccer players with chronic adductor-related groin pain.

    PubMed

    Belhaj, K; Meftah, S; Mahir, L; Lmidmani, F; Elfatimi, A

    2016-11-01

    This study aims to compare the isokinetic profile of hip abductor and adductor muscle groups between soccer players suffering from chronic adductor-related groin pain (ARGP), soccer players without ARGP and healthy volunteers from general population. Study included 36 male professional soccer players, who were randomly selected and followed-up over two years. Of the 21 soccer players eligible to participate in the study, 9 players went on to develop chronic ARGP and 12 players did not. Ten healthy male volunteers were randomly selected from the general population as a control group. Comparison between the abductor and adductor muscle peak torques for players with and without chronic ARGP found a statistically significant difference on the dominant and non-dominant sides (p < .005), with the abductor muscle significantly stronger than the adductor muscle. In the group of healthy volunteers, the adductor muscle groups were significantly stronger than the abductor muscle groups on both dominant and non-dominant sides (p < .05). For the group of players who had developed chronic ARGP, abductor-adductor torque ratios were significantly higher on the affected side (p = .008). The adductor muscle strength was also significantly decreased on the affected side. This imbalance appears to be a risk factor for adductor-related groin injury. Therefore, restoring the correct relationship between these two agonist and antagonist hip muscles may be an important preventative measure that should be a primary concern of training and rehabilitation programmes.

  3. Activation of the hip adductor muscles varies during a simulated weight-bearing task.

    PubMed

    Hides, Julie A; Beall, Paula; Franettovich Smith, Melinda M; Stanton, Warren; Miokovic, Tanja; Richardson, Carolyn

    2016-01-01

    To investigate the pattern of muscle activation of the individual hip adductor muscles using a standardised simulated unilateral weight-bearing task. A repeated measures design. Laboratory. 20 healthy individuals (11 females, 9 males) participated in the study. Age ranged from 20 to 25 years. Surface electromyography recordings from adductor magnus and adductor longus muscles were taken at levels representing 10-50% of body weight during a simulated weight-bearing task. Electromyography (EMG) data were normalised to maximal voluntary isometric contraction. The adductor magnus was recruited at significantly higher levels than the adductor longus muscle during a simulated weight-bearing task performed across 10-50% of body weight (p < 0.01). Adductor magnus and adductor longus muscles are recruited to different extents during a simulated weight-bearing task. This information should be considered when selecting exercises for management and prevention of groin strains. Closed chain exercises with weight-bearing through the lower limb are more likely to recruit the adductor magnus muscle over the adductor longus muscle. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. The hip adductor muscle group in caviomorph rodents: anatomy and homology.

    PubMed

    García-Esponda, César M; Candela, Adriana M

    2015-06-01

    Anatomical comparative studies including myological data of caviomorph rodents are relatively scarce, leading to a lack of use of muscular features in cladistic and morphofunctional analyses. In rodents, the hip adductor muscles constitute an important group of the hindlimb musculature, having an important function during the beginning of the stance phase. These muscles are subdivided in several distinct ways in the different clades of rodents, making the identification of their homologies hard to establish. In this contribution we provide a detailed description of the anatomical variation of the hip adductor muscle group of different genera of caviomorph rodents and identify the homologies of these muscles in the context of Rodentia. On this basis, we identify the characteristic pattern of the hip adductor muscles in Caviomorpha. Our results indicate that caviomorphs present a singular pattern of the hip adductor musculature that distinguishes them from other groups of rodents. They are characterized by having a single m. adductor brevis that includes solely its genicular part. This muscle, together with the m. gracilis, composes a muscular sheet that is medial to all other muscles of the hip adductor group. Both muscles probably have a synergistic action during locomotion, where the m. adductor brevis reinforces the multiple functions of the m. gracilis in caviomorphs. Mapping of analyzed myological characters in the context of Rodentia indicates that several features are recovered as potential synapomorphies of caviomorphs. Thus, analysis of the myological data described here adds to the current knowledge of caviomorph rodents from anatomical and functional points of view, indicating that this group has features that clearly differentiate them from other rodents. Copyright © 2015 Elsevier GmbH. All rights reserved.

  5. The adequate rocuronium dose required for complete block of the adductor muscles of the thigh.

    PubMed

    Fujimoto, M; Kawano, K; Yamamoto, T

    2018-03-01

    Rocuronium can prevent the obturator jerk during transurethral resection of bladder tumors. We investigated the adequate rocuronium dose required for complete block of the thigh adductor muscles, and its correlation with individual responses of the adductor pollicis muscle to rocuronium. Eleven patients scheduled for transurethral resection of bladder tumors under general anesthesia were investigated. After general anesthesia induction, neuromuscular monitoring of the adductor pollicis muscle and ultrasonography-guided stimulation of the obturator nerve was commenced. Rocuronium, 0.15 mg/kg, was repeatedly administered intravenously. The adequate rocuronium dose required for complete block of the thigh muscles, defined as the cumulative dose of rocuronium administered until that time, and its correlation with the first twitch response of the adductor pollicis muscle on train-of-four stimulation after initial rocuronium administration was analyzed. The rocuronium dose found adequate for complete block of the thigh muscles was 0.30 mg/kg in seven patients and 0.45 mg/kg in the remaining four patients, which did not correlate with the first twitch response. At the time of complete block of the thigh muscles, the neuromuscular blockade level of the adductor pollicis muscle varied greatly, although the level was never more profound than a post-tetanic count of 1. Although the response of the adductor pollicis muscle to rocuronium cannot be used to determine the adequate rocuronium dose required for complete block of the thigh muscles, intense blockade, with maintenance of post-tetanic count at ≤ 1 in the adductor pollicis muscle is essential to prevent the obturator jerk. © 2017 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  6. EMG of the hip adductor muscles in six clinical examination tests.

    PubMed

    Lovell, Gregory A; Blanch, Peter D; Barnes, Christopher J

    2012-08-01

    To assess activation of muscles of hip adduction using EMG and force analysis during standard clinical tests, and compare athletes with and without a prior history of groin pain. Controlled laboratory study. 21 male athletes from an elite junior soccer program. Bilateral surface EMG recordings of the adductor magnus, adductor longus, gracilis and pectineus as well as a unilateral fine-wire EMG of the pectineus were made during isometric holds in six clinical examination tests. A load cell was used to measure force data. Test type was a significant factor in the EMG output for all four muscles (all muscles p < 0.01). EMG activation was highest in Hips 0 or Hips 45 for adductor magnus, adductor longus and gracilis. EMG activation for pectineus was highest in Hips 90. Injury history was a significant factor in the EMG output for the adductor longus (p < 0.05), pectineus (p < 0.01) and gracilis (p < 0.01) but not adductor magnus. For force data, clinical test type was a significant factor (p < 0.01) with Hips 0 being significantly stronger than Hips 45, Hips 90 and Side lay. BMI (body mass index) was a significant factor (p < 0.01) for producing a higher force. All other factors had no significant effect on the force outputs. Hip adduction strength assessment is best measured at hips 0 (which produced most force) or 45° flexion (which generally gave the highest EMG output). Muscle EMG varied significantly with clinical test position. Athletes with previous groin injury had a significant fall in some EMG outputs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Scaling and Accommodation of Jaw Adductor Muscles in Canidae

    PubMed Central

    Kemp, Graham J.; Jeffery, Nathan

    2016-01-01

    ABSTRACT The masticatory apparatus amongst closely related carnivoran species raises intriguing questions about the interplay between allometry, function, and phylogeny in defining interspecific variations of cranial morphology. Here we describe the gross structure of the jaw adductor muscles of several species of canid, and then examine how the muscles are scaled across the range of body sizes, phylogenies, and trophic groups. We also consider how the muscles are accommodated on the skull, and how this is influenced by differences of endocranial size. Data were collected for a suite of morphological metrics, including body mass, endocranial volume, and muscle masses and we used geometric morphometric shape analysis to reveal associated form changes. We find that all jaw adductor muscles scale isometrically against body mass, regardless of phylogeny or trophic group, but that endocranial volume scales with negative allometry against body mass. These findings suggest that head shape is partly influenced by the need to house isometrically scaling muscles on a neurocranium scaling with negative allometry. Principal component analysis suggests that skull shape changes, such as the relatively wide zygomatic arches and large sagittal crests seen in species with higher body masses, allow the skull to accommodate a relative enlargement of the jaw adductors compared with the endocranium. Anat Rec, 299:951–966, 2016. © 2016 The Authors The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc. PMID:27103346

  8. Improved adductor function after canine recurrent laryngeal nerve injury and repair using muscle progenitor cells.

    PubMed

    Paniello, Randal C; Brookes, Sarah; Bhatt, Neel K; Bijangi-Vishehsaraei, Khadijeh; Zhang, Hongji; Halum, Stacey

    2017-12-08

    Muscle progenitor cells (MPCs) can be isolated from muscle samples and grown to a critical mass in culture. They have been shown to survive and integrate when implanted into rat laryngeal muscles. In this study, the ability of MPC implants to enhance adductor function of reinnervated thyroarytenoid muscles was tested in a canine model. Animal study. Sternocleidomastoid muscle samples were harvested from three canines. Muscle progenitor cells were isolated and cultured to 10 7 cells over 4 to 5 weeks, then implanted into right thyroarytenoid muscles after ipsilateral recurrent laryngeal nerve transection and repair. The left sides underwent the same nerve injury, but no cells were implanted. Laryngeal adductor force was measured pretreatment and again 6 months later, and the muscles were harvested for histology. Muscle progenitor cells were successfully cultured from all dogs. Laryngeal adductor force measurements averaged 60% of their baseline pretreatment values in nonimplanted controls, 98% after implantation with MPCs, and 128% after implantation with motor endplate-enhanced MPCs. Histology confirmed that the implanted MPCs survived, became integrated into thyroarytenoid muscle fibers, and were in close contact with nerve endings, suggesting functional innervation. Muscle progenitor cells were shown to significantly enhance adductor function in this pilot canine study. Patient-specific MPC implantation could potentially be used to improve laryngeal function in patients with vocal fold paresis/paralysis, atrophy, and other conditions. Further experiments are planned. NA. Laryngoscope, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  9. The Jaw Adductor Muscle Complex in Teleostean Fishes: Evolution, Homologies and Revised Nomenclature (Osteichthyes: Actinopterygii)

    PubMed Central

    Datovo, Aléssio; Vari, Richard P.

    2013-01-01

    The infraclass Teleostei is a highly diversified group of bony fishes that encompasses 96% of all species of living fishes and almost half of extant vertebrates. Evolution of various morphological complexes in teleosts, particularly those involving soft anatomy, remains poorly understood. Notable among these problematic complexes is the adductor mandibulae, the muscle that provides the primary force for jaw adduction and mouth closure and whose architecture varies from a simple arrangement of two segments to an intricate complex of up to ten discrete subdivisions. The present study analyzed multiple morphological attributes of the adductor mandibulae in representatives of 53 of the 55 extant teleostean orders, as well as significant information from the literature in order to elucidate the homologies of the main subdivisions of this muscle. The traditional alphanumeric terminology applied to the four main divisions of the adductor mandibulae – A1, A2, A3, and Aω – patently fails to reflect homologous components of that muscle across the expanse of the Teleostei. Some features traditionally used as landmarks for identification of some divisions of the adductor mandibulae proved highly variable across the Teleostei; notably the insertion on the maxilla and the position of muscle components relative to the path of the ramus mandibularis trigeminus nerve. The evolutionary model of gain and loss of sections of the adductor mandibulae most commonly adopted under the alphanumeric system additionally proved ontogenetically incongruent and less parsimonious than a model of subdivision and coalescence of facial muscle sections. Results of the analysis demonstrate the impossibility of adapting the alphanumeric terminology so as to reflect homologous entities across the spectrum of teleosts. A new nomenclatural scheme is proposed in order to achieve congruence between homology and nomenclature of the adductor mandibulae components across the entire Teleostei. PMID

  10. A Preliminary Study on the Pattern, the Physiological Bases and the Molecular Mechanism of the Adductor Muscle Scar Pigmentation in Pacific Oyster Crassostrea gigas

    PubMed Central

    Yu, Wenchao; He, Cheng; Cai, Zhongqiang; Xu, Fei; Wei, Lei; Chen, Jun; Jiang, Qiuyun; Wei, Na; Li, Zhuang; Guo, Wen; Wang, Xiaotong

    2017-01-01

    The melanin pigmentation of the adductor muscle scar and the outer surface of the shell are among attractive features and their pigmentation patterns and mechanism still remains unknown in the Pacific oyster Crassostrea gigas. To study these pigmentation patterns, the colors of the adductor muscle scar vs. the outer surface of the shell on the same side were compared. No relevance was found between the colors of the adductor muscle scars and the corresponding outer surface of the shells, suggesting that their pigmentation processes were independent. Interestingly, a relationship between the color of the adductor muscle scars and the dried soft-body weight of Pacific oysters was found, which could be explained by the high hydroxyl free radical scavenging capacity of the muscle attached to the black adductor muscle scar. After the transcriptomes of pigmented and unpigmented adductor muscles and mantles were studied by RNAseq and compared, it was found that the retinol metabolism pathway were likely to be involved in melanin deposition on the adductor muscle scar and the outer surface of the shell, and that the different members of the tyrosinase or Cytochrome P450 gene families could play a role in the independent pigmentation of different organs. PMID:28955252

  11. Power of performance of the thumb adductor muscles: effect of laterality and gender.

    PubMed

    Gutnik, Boris; Nash, Derek; Ricacho, Norberto; Hudson, Grant; Skirius, Jonas

    2006-01-01

    The aim of this work was to originally measure mechanical power output of the thumb adductor muscles during fast adduction of the thumb in the horizontal plane. This information will contribute to biomechanical guidelines to help clinicians, sport medicine and rehabilitation specialists in the objective functional evaluation of abnormalities of thumb adductors. Participants performed 20 fast adductions in response to audio signals. Maximum and average angular velocity and angular acceleration were measured. Tangential components of these parameters were then derived. The force of adduction was obtained from the tangential acceleration and the mass of the rotational system. The power was then calculated as the product of the force of adduction and average tangential velocity during the acceleration phase of adduction. All young and untrained males and females were strictly right handed. There was no significant difference in power between dominant and nondominant muscles for either males or females, but males developed significantly more power than females. Because adduction was performed at maximal speed, these data may be explained by the influence of parallel and series elastic elements in the muscle, as well as by influence of fast twitch fibers. Power may be used as a clinical index of the effectiveness of muscle contraction. The similarity of power outputs from dominant and nondominant thumb adductor muscles of right-handers can suggest a classical Bernstein approach. This theoretical approach purports that peripheral factors can distort central commands projected to dominant and nondominant extremities.

  12. Interarytenoid muscle botox injection for treatment of adductor spasmodic dysphonia with vocal tremor.

    PubMed

    Kendall, Katherine A; Leonard, Rebecca J

    2011-01-01

    Up to one-third of patients presenting with adductor spasmodic dysphonia will have an associated vocal tremor. These patients may not respond fully to treatment using thyroarytenoid (TA) muscle botulinum toxin (Botox) injection. Treatment failures are attributed to the involvement of multiple muscle groups in the tremor. This study evaluates the results of combined interarytenoid (IA) and TA muscle Botox injection in a group of 27 patients with adductor spasmodic dysphonia and vocal tremor and in four patients with severe vocal tremor alone. Patient-satisfaction data were reviewed retrospectively. Pre- and postinjection acoustic data were collected prospectively. Acoustic measures of fundamental frequency and cycle-by-cycle variability in frequency (jitter) and intensity (shimmer) were obtained from 15 patients' sustained vowel productions. Measures were collected after TA muscle injection, alone, and after combined TA and IA (TA+IA) muscle injections. In addition, two experienced voice clinicians blindly assessed tremor severity from recordings made for each patient in the two conditions. Patients were also queried regarding their satisfaction with the results of the injections and whether they desired to continue receiving TA+IA treatment. Significant improvement in all acoustic measures except for % jitter was observed after the TA+IA muscle injections. Listeners identified voice samples after TA+IA muscle injections as demonstrating less tremor in 73% of the paired comparisons. Sixty-seven percent of the patients with spasmodic dysphonia and vocal tremor wished to continue to receive IA muscle injections. Only one patient with severe vocal tremor wished to continue with injections. The addition of an IA muscle Botox injection to the treatment of patients with a combination adductor spasmodic dysphonia and vocal tremor may improve voice outcomes. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  13. Monitoring recovery from rocuronium-induced neuromuscular block using acceleromyography at the trapezius versus the adductor pollicis muscle: an observational trial.

    PubMed

    Soltesz, Stefan; Stark, Christian; Noé, Karl G; Anapolski, Michael; Mencke, Thomas

    2016-06-01

    Positioning for surgery can restrict access to the patient's hand, thereby limiting assessment of the response at the adductor pollicis muscle to ulnar nerve stimulation. We evaluated a novel site to assess neuromuscular block by stimulating the accessory nerve and measuring the acceleromyographic response at the trapezius muscle. In this prospective non-blinded observational study, we assessed neuromuscular transmission in anesthetized adult female patients undergoing elective laparoscopic gynecological surgery. We performed the assessment by simultaneous recording acceleromyographic responses with the TOF-Watch(®) SX monitor at both the right adductor pollicis and left trapezius muscles. The neuromuscular block was achieved using rocuronium 0.3 mg·kg(-1), and the repeatability, time course, and limits of agreement (Bland-Altman) of responses were compared at the two recording sites. The primary endpoint was the 90% train-of-four (TOF) recovery time with other endpoints included the onset time of the block, maximum T1 depression, time to 25% T1 recovery, and recovery time course of the T1 response and TOF ratio. Thirty-six patients were enrolled with responses obtained from 27 subjects. The variability of baseline responses recorded at the trapezius muscle was larger than that recorded at the adductor pollicis muscle, as determined by their mean (SD) repeatability coefficients [twitch height T1, 6.1 (1.9)% and 4.2 (1.6)%, respectively; P = 0.001; TOF ratio, 6.2 (2.1)% and 4.3 (1.7)%, respectively; P = 0.001]. The recorded responses showed relatively narrow limits of agreement. The onset time of the block was 0.3 min earlier at the trapezius muscle than at the adductor pollicis muscle [2.3 (0.8) min and 2.6 (0.7) min, respectively; P = 0.007], with limits of agreement ranging from 1.6 min earlier to 1.0 min later. The time to 25% T1 recovery was 1.8 min earlier at the trapezius muscle than at the adductor pollicis muscle [18.2 (5.7) min and 20.0 (5.2) min

  14. From untargeted LC-QTOF analysis to characterisation of opines in abalone adductor muscle: Theory meets practice.

    PubMed

    Venter, Leonie; Jansen van Rensburg, Peet J; Loots, Du Toit; Vosloo, Andre; Lindeque, Jeremie Zander

    2017-12-15

    Abalone have a unique ability to use pyruvate, various amino acids and dehydrogenases, to produce opines as means to prevent the accumulation of NADH during anaerobic conditions. In this study, the theoretical masses, formulae and fragment patterns of butylated opines were used to predict which of these compounds could be found in the abalone adductor muscle using untargeted liquid chromatography quadrupole time-of flight-mass spectrometry. These findings were validated using synthesised opine standards. In essence alanopine, lysopine, strombine and tauropine produced in abalone adductor muscle could be characterised using the highest identification confidence levels. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Temporal changes in sarcomere lesions of rat adductor longus muscles during hindlimb reloading

    NASA Technical Reports Server (NTRS)

    Krippendorf, B. B.; Riley, D. A.

    1994-01-01

    Focal sarcomere disruptions were previously observed in adductor longus muscles of rats flown approximately two weeks aboard the Cosmos 1887 and 2044 biosatellite flights. These lesions, characterized by breakage and loss of myofilaments and Z-line streaming, resembled damage induced by unaccustomed exercise that includes eccentric contractions in which muscles lengthen as they develop tension. We hypothesized that sarcomere lesions in atrophied muscles of space flow rats were not produced in microgravity by muscle unloading but resulted from muscle reloading upon re-exposure to terrestrial gravity. To test this hypothesis, we examined temporal changes in sarcomere integrity of adductor longus muscles from rats subjected to 12.5 days of hindlimb suspension unloading and subsequent reloading by return to vivarium cages for 0, 6, 12, or 48 hours of normal weightbearing. Our ultrastructural observations suggested that muscle unloading (0 h reloading) induced myofibril misalignment associated with myofiber atrophy. Muscle reloading for 6 hours induced focal sarcomere lesions in which cross striations were abnormally widened. Such lesions were electron lucent due to extensive myofilament loss. Lesions in reloaded muscles showed rapid restructuring. By 12 hours of reloading, lesions were moderately stained foci and by 48 hours darkly stained foci in which the pattern of cross striations was indistinct at the light and electron microscopic levels. These lesions were spanned by Z-line-like electron dense filamentous material. Our findings suggest a new role for Z-line streaming in lesion restructuring: rather than an antecedent to damage, this type of Z-line streaming may be indicative of rapid, early sarcomere repair.

  16. Cortical Silent Period Reveals Differences Between Adductor Spasmodic Dysphonia and Muscle Tension Dysphonia.

    PubMed

    Samargia, Sharyl; Schmidt, Rebekah; Kimberley, Teresa Jacobson

    2016-03-01

    The pathophysiology of adductor spasmodic dysphonia (AdSD), like other focal dystonias, is largely unknown. The purposes of this study were to determine (a) cortical excitability differences between AdSD, muscle tension dysphonia (MTD), and healthy controls; (b) distribution of potential differences in cranial or skeletal muscle; and (c) if cortical excitability measures assist in the differential diagnosis of AdSD and MTD. Ten participants with adductor spasmodic dysphonia, 8 with muscle tension dysphonia, and 10 healthy controls received single and paired pulse transcranial magnetic stimulation (TMS) to the primary motor cortex contralateral to tested muscles, first dorsal interosseus (FDI), and masseter. We tested the hypothesis that cortical excitability measures in AdSD would be significantly different from those in MTD and healthy controls. In addition, we hypothesized that there would be a correlation between cortical excitability measures and clinical voice severity in AdSD. Cortical silent period duration in masseter and FDI was significantly shorter in AdSD than MTD and healthy controls. Other measures failed to demonstrate differences. There are differences in cortical excitability between AdSD, MTD, and healthy controls. These differences in the cortical measure of both the FDI and masseter muscles in AdSD suggest widespread dysfunction of the GABAB mechanism may be a pathophysiologic feature of AdSD, similar to other forms of focal dystonia. Further exploration of the use of TMS to assist in the differential diagnosis of AdSD and MTD is warranted. © The Author(s) 2015.

  17. Cortical silent period reveals differences between adductor spasmodic dysphonia and muscle tension dysphonia

    PubMed Central

    Samargia, Sharyl; Schmidt, Rebekah; Kimberley, Teresa Jacobson

    2015-01-01

    Background The pathophysiology of adductor spasmodic dysphonia (AdSD), like other focal dystonias, is largely unknown. Objective The purposes of this study were to determine 1) cortical excitability differences between AdSD, muscle tension dysphonia (MTD) and healthy controls 2) distribution of potential differences in cranial or skeletal muscle, and 3) if cortical excitability measures assist in the differential diagnosis of AdSD and MTD. Methods 10 participants with adductor spasmodic dysphonia, 8 with muscle tension dysphonia and 10 healthy controls received single and paired pulse transcranial magnetic stimulation (TMS) to the primary motor cortex contralateral to tested muscles, first dorsal interosseus (FDI) and masseter. We tested the hypothesis that cortical excitability measures in AdSD would be significantly different than in MTD and healthy. In addition, we hypothesized there would be a correlation between cortical excitability measures and clinical voice severity in AdSD. Results Cortical silent period (CSP) duration in masseter and FDI was significantly shorter in AdSD than MTD and healthy controls. Other measures failed to demonstrate differences. Conclusion There are differences in cortical excitability between AdSD, MTD and healthy controls. These differences in the cortical measure of both the FDI and masseter muscles in AdSD suggest widespread dysfunction of the GABAB mechanism may be a pathophysiologic feature of AdSD, similar to other forms of focal dystonia. Further exploration of the use of TMS to assist in the differential diagnosis of AdSD and MTD is warranted. PMID:26089309

  18. Reversal of neuromuscular block with sugammadex: a comparison of the corrugator supercilii and adductor pollicis muscles in a randomized dose-response study.

    PubMed

    Yamamoto, S; Yamamoto, Y; Kitajima, O; Maeda, T; Suzuki, T

    2015-08-01

    Neuromuscular monitoring using the corrugator supercilii muscle is associated with a number of challenges. The aim of this study was to assess reversal of a rocuronium-induced neuromuscular blockade with sugammadex according to monitoring either using the corrugator supercilii muscle or the adductor pollicis muscle. We hypothesized that a larger dose of sugammadex would be required to obtain a train-of-four (TOF) ratio of 1.0 with the corrugator supercilii muscle than with the adductor pollicis muscle. Forty patients aged 20-60 years and 40 patients aged ≥ 70 years were enrolled. After induction of anesthesia, we recorded the corrugator supercilii muscle response to facial nerve stimulation and the adductor pollicis muscle response to ulnar nerve stimulation using acceleromyography. All patients received 1 mg/kg rocuronium. When the first twitch (T1) of TOF recovered to 10% of control values at the corrugator supercilii, rocuronium infusion was commenced to maintain a T1 of 10% of the control at the corrugator supercilii. Immediately after discontinuation of rocuronium infusion, 2 mg/kg or 4 mg/kg of sugammadex was administered. The time for recovery to a TOF ratio of 1.0 and the number of patients not reaching a TOF ratio of 1.0 by 5 min at each dose and muscle was recorded. When neuromuscular block at the corrugator supercilii was maintained at a T1 of 10% of control, that at the adductor pollicis was deep (post-tetanic count ≤ 5). Sugammadex 4 mg/kg completely antagonized neuromuscular block at both muscles within 5 min. The time to a TOF ratio of 1.0 at the adductor pollicis was significantly longer in the group ≥ 70 years than the group 20-60 years (mean (SD): 178 (42.8) s vs. 120 (9.4) s, P < 0.0001). In contrast, 2 mg/kg sugammadex reversed neuromuscular blockade at the corrugator supercilii but not at the adductor pollicis, with 10 patients in the group 20-60 years and 8 patients in the group ≥ 70 years requiring an additional

  19. Effect on laryngeal adductor function of vincristine block of posterior cricoarytenoid muscle 3 to 5 months after recurrent laryngeal nerve injury.

    PubMed

    Paniello, Randal C; Park, Andrea

    2015-06-01

    It has been shown in a canine model that a single injection of vincristine into the posterior cricoarytenoid (PCA) muscle at the time of recurrent laryngeal nerve (RLN) injury effectively blocks its reinnervation and results in improved adductor strength. But clinically, such injuries are usually diagnosed weeks or months after onset. Vincristine injection does not affect a muscle that is already innervated; thus, there is a limited time frame following RLN injury during which a vincristine injection could effectively improve ultimate laryngeal adductor functional recovery. A series of delayed injections was performed in a canine model and results assessed. Animal (canine) experiment. The RLN was transected and repaired, and vincristine (0.4 mg) was injected into the PCA muscle at the time of injury (n=12) or 3, 4, and 5 months later (n=8 each study group). Six months after RLN injury, laryngeal adductor function was measured. Results of vincristine injection without RLN injury (n=6) and longer-term (12 months) follow-up for time zero injections (n=4) are also reported. The animals injected at time zero had better adductor function than non-injected controls, as reported previously, and this result was further increased at 12 months. The 3-month delay gave results similar to the time zero group. The 5-month delay group showed no vincristine benefit, and the 4-month delay group gave an intermediate result. Vincristine to the PCA had no effect on adductor function when the RLN was left intact. Plasma levels showed 19% of injected vincristine reached systemic circulation, which was cleared within 69 hours. Vincristine injection of the PCA muscle after RLN injury, which blocks this antagonist muscle from synkinetic reinnervation, leads to improved laryngeal adductor functional recovery. The window of opportunity to apply this treatment closes by 4 months after RLN injury in the canine model. Human RLN recovery follows a similar time course and can reasonably be

  20. Effect on Laryngeal Adductor Function of Vincristine Block of Posterior Cricoarytenoid Muscle 3-5 Months After Recurrent Laryngeal Nerve Injury

    PubMed Central

    Paniello, Randal C.; Park, Andrea

    2015-01-01

    Objectives It has been shown, in a canine model, that a single injection of vincristine into the PCA muscle at the time of recurrent laryngeal nerve (RLN) injury effectively blocks its reinnervation and results in improved adductor strength. But clinically, such injuries are usually diagnosed weeks or months after onset. Vincristine injection does not affect a muscle that is already innervated; thus, there is a limited time frame following RLN injury during which a vincristine injection could effectively improve ultimate laryngeal adductor functional recovery. A series of delayed injections were performed in a canine model and results assessed. Study Design Animal (canine) experiment. Methods The RLN was transected and repaired, and vincristine (0.4 mg) was injected into the PCA muscle at the time of injury (n=12), or at 3, 4, and 5 months later (n=8 each study group). Six months after RLN injury, laryngeal adductor function was measured. Results of vincristine injection without RLN injury (n=6), and longer-term (12 months) follow-up for time zero injections (n=4), are also reported. Results The animals injected at time zero had better adductor function than non-injected controls, as reported previously, and this result was further increased at 12 months. The 3-month delay gave results similar to the time zero group. The 5-month delay group showed no vincristine benefit, and the 4-month delay group gave an intermediate result. Vincristine to the PCA had no effect on adductor function when the RLN was left intact. Plasma levels showed 19% of injected vincristine reached systemic circulation, which was cleared within 69 hours. Conclusions Vincristine injection of the PCA muscle after RLN injury, which blocks this functional recovery. The window of opportunity to apply this treatment closes by four months after RLN injury in the canine model. Human RLN recovery follows a similar time course and can reasonably be expected to have a similar therapeutic window. PMID

  1. Sports hernia repair with adductor tenotomy.

    PubMed

    Harr, J N; Brody, F

    2017-02-01

    Sports hernias, or athletic pubalgia, is common in athletes, and primarily involves injury to the fascia, muscles, and tendons of the inguinal region near their insertion onto the pubic bone. However, management varies widely, and rectus and adductor tenotomies have not been adequately described. The purpose of this manuscript is to demonstrate a suture repair and a rectus and adductor longus tenotomy technique for sports hernias. After magnetic-resonance-imaging confirmation of sports hernias with rectus and adductor tendonitis, 22 patients underwent a suture herniorrhaphy with adductor tenotomy. The procedure is performed through a 4-cm incision, and a fascial release of the rectus abdominis and adductor tenotomy is performed to relieve the opposing vector forces on the pubic bone. All 22 patients returned to their respective sports and regained their ability to perform at a high level, including professional status. No further surgery was required. In athletes with MRI confirmation of rectus and adductor longus injuries, tenotomies along with a herniorraphy may improve outcomes. A suture repair to reinforce the inguinal floor prevents mesh-related complications, especially in young athletes.

  2. "Pollical palmar interosseous muscle" (musculus adductor pollicis accessorius): attachments, innervation, variations, phylogeny, and implications for human evolution and medicine.

    PubMed

    Bello-Hellegouarch, Gaelle; Aziz, M Ashraf; Ferrero, Eva M; Kern, Michael; Francis, Nadia; Diogo, Rui

    2013-03-01

    Most atlases and textbooks dealing with human anatomy do not refer to the "pollical palmar interosseous" (PPI) muscle of Henle. In order to undertake a fresh and detailed study of this muscle and to thus better understand human comparative anatomy and evolution, we: 1) analyze the frequency of the PPI in a large sample of human hands; 2) describe the attachments, innervation and varieties of the PPI in these hands; 3) compare the data obtained with the information available in the literature; and 4) discuss the phylogenetic origin of the PPI and the implications of our observations and comparisons for medicine and for the understanding of human evolutionary history. Within the 72 hands dissected by us, the PPI is present in 67 hands (93%), commonly having a single muscular branch, originating from the medial side of the base of metacarpal I only, inserting onto the medial side of the base of the pollical proximal phalanx and/or surrounding structures (e.g., ulnar sesamoid bone, wing tendon of extensor apparatus), and passing at least partially, and usually mainly, medial to the princeps pollicis artery. A careful study of the human PPI, as well as a detailed comparison with other mammals, strongly suggest that the muscle is evolutionarily derived from the adductor pollicis, and namely from its oblique head. Therefore, we propose that PPI should be designated by the name musculus adductor pollicis accessorius, which indicates that the muscle is most likely a de novo structure derived from the adductor pollicis. Copyright © 2012 Wiley Periodicals, Inc.

  3. TVT ABBREVO: cadaveric study of tape position in foramen obturatum and adductor region.

    PubMed

    Hubka, Petr; Nanka, Ondrej; Masata, Jaromir; Martan, Alois; Svabik, Kamil

    2016-07-01

    The aim of the study was to describe fixation of the TVT ABBREVO and establish whether the tape penetrates through obturator muscles and membrane (obturator complex) into the adductor region and, if so, how far it penetrates. Eight formalin-embalmed female cadavers were used to simulate TVT ABBREVO surgery (totalling 16 insertions). Following tape insertion, dissection was performed and ends of the tape were identified. In cases of penetration, the length of tape penetrating into the adductor region was measured. Of the 16 cases, the tape ended in the obturator membrane in eight, in the internal obturator muscle in one, and penetrated through the obturator membrane into the external obturator muscle in five, where it remained. In two cases, it penetrated through the obturator internus muscle, obturator membrane and obturator externus muscle into the group of thigh adductors; one penetration was by 3 mm and the second by 10 mm. No contact with the obturator nerve or its branches was noted in any case. No TVT contact with the obturator nerve was noted; tape penetrated into the adductor region in two of the 16 cases.

  4. Proximate composition and nutritional evaluation of the adductor muscle of pen shell.

    PubMed

    Wu, Shengjun; Wu, Yuping

    2017-07-01

    The proximate composition of pen shell adductor muscle (PSAM) was determined, and its nutrition value was evaluated. Proximate composition analysis indicated that PSAM contained 91.07% (w/w) protein, 5.77% (w/w) ash, and 2.46% (w/w) fat. Calcium was the predominant mineral followed by zinc and then iron. The amino acid profile was in accordance with the recommended pattern of FAO/WHO except for histidine. At the same time, the first limiting amino acid was histidine. Fatty acid composition showed that docosahexaenoic acid was the major fatty acid, followed by palmitic, stearic, and arachidonic acids. Results indicated that PSAM was rich in nutrition and may be developed as a functional food.

  5. Evaluation of the thoraco-laryngeal reflex ('slap test') as an indicator of laryngeal adductor myopathy in the horse.

    PubMed

    Newton-Clarke, M J; Divers, T J; Valentine, B A

    1994-09-01

    A study was conducted over a 12 month period to assess the accuracy of the 'slap test' in the diagnosis of laryngeal adductor myopathy. The thoraco-laryngeal reflexes of 15 horses with no clinical signs of idiopathic laryngeal hemiplegia (ILH) were recorded using a video-endoscope. These 'slap test' responses were examined independently by 3 assessors. The horses were subsequently subjected to euthanasia and samples taken from the cricoarytenoideus lateralis (CAL) muscles for histopathological examination and assessment of denervation atrophy. Despite normal adductory responses, moderate to severe atrophy of the left CAL muscles was seen in 5 horses. The remaining horses had varying degrees of adductor myopathy, invariably worse in the left side of the larynx. The 'slap test' as performed in this study was therefore unable to differentiate between horses with moderate to severe muscle changes and those without, making it useless as a diagnostic test for adductor myopathy. The reason for the preservation in adductor function despite advanced histological atrophy of the muscle may lie in the degree of reinnervation found in the muscles.

  6. Functional reinnervation of vocal folds after selective laryngeal adductor denervation-reinnervation surgery for spasmodic dysphonia.

    PubMed

    DeConde, Adam S; Long, Jennifer L; Armin, Bob B; Berke, Gerald S

    2012-09-01

    Selective laryngeal adductor denervation-reinnervation surgery (SLAD-R) offers a viable surgical alternative for patients with adductor spasmodic dysphonia refractory to botulinum toxin injections. SLAD-R selectively denervates the symptomatic thyroarytenoid muscle by dividing the distal adductor branch of the recurrent laryngeal nerve (RLN), and preventing reinnervation, by the proximal RLN and maintaining vocal fold bulk and tone by reinnervating the distal RLN with the ansa cervicalis. We present a patient who had previously undergone successful SLAD-R but presented 10 years postoperatively with a new regional dystonia involving his strap muscles translocated to his reinnervated larynx by his previous ansa-RLN neurorraphy. The patient's symptomatic vocal fold adduction resolved completely on division of the ansa-RLN neurorraphy confirming successful selective functional reinnervation of vocal fold adductors by the ansa cervicalis. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  7. Clinical recovery of two hip adductor longus ruptures: a case-report of a soccer player

    PubMed Central

    2013-01-01

    Background Non-operative treatment of acute hip adductor longus ruptures in athletes has been described in the literature. However, very limited information concerning the recovery of this type of injury exists. This case represented a unique possibility to study the recovery of two acute adductor longus ruptures, using novel, reliable and validated assessment methods. Case presentation A 22-year old male soccer player (Caucasian) sustained two subsequent acute adductor longus ruptures, one in each leg. The injuries occurred 10 months apart, and were treated non-surgically in both situations. He was evaluated using hip-strength assessments, self-report and ultrasonography until complete muscle-strength recovery of the hip adductors had occurred. The player was able to participate in a full soccer training session without experiencing pain 15 weeks after the first rupture, and 12 weeks after the second rupture. Full hip adductor muscle-strength recovery was obtained 52 weeks after the first rupture and 10 weeks after the second rupture. The adductor longus injuries, as verified by initial ultrasonography (10 days post-injury), showed evidence of a complete tendon rupture in both cases, with an almost identical imaging appearance. It was only at 6 and 10 weeks ultrasonographic follow-up that the first rupture was found to include a larger anatomical area than the second rupture. Conclusion From this case we can conclude that two apparently similar hip adductor longus ruptures, verified by initial ultrasonography (10 days post-injury), can have very different hip adductor strength recovery times. Assessment of adductor strength recovery may therefore in the future be a useful and important additional measure for determining when soccer players with hip adductor longus ruptures can return safely to play. PMID:23693119

  8. Comparative biochemical composition in gonad and adductor muscle of triploid and diploid catarina scallop (Argopecten ventricosus Sowerby II, 1842).

    PubMed

    Ruiz-Verdugo, C A.; Racotta, I S.; Ibarra, A M.

    2001-05-15

    Biochemical components of gonad and adductor muscle for diploid and triploid catarina scallop, Argopecten ventricosus, were evaluated and compared at four periods in 1 year (January, April, June, and October). Two comparisons were done. The first one compared an untreated control (diploid) vs. a triploidy-treated group for which the percentage of triploids was 57%. The second comparison was done on a group derived from within the triploidy-treated group, separating diploids (internal control) from triploids ('putative triploids'). Regardless of which comparison, in the gonad diploid scallops had larger concentrations of proteins, carbohydrates, lipids, and acylglycerols than triploid scallops. This reflects the maturation processes in diploid scallops vs. the sterility seen in most triploid scallops, and it is particularly supported by the consistently larger concentration of acylglycerols in gonads of diploids than in triploids. The gonad index of the internal control (diploid) group was significantly larger than that seen in the putative triploid group at all sampling periods but October, when none of the gonad biochemical components were different between ploidy groups.Triploid scallops had a significantly larger muscle index than diploids from April to October. This can be caused by a larger gain in muscle tissue in triploids than diploids from January to June. However, there were no consistent differences in any of the biochemical components evaluated in adductor muscle of diploids and triploids. The use of freshly ingested food rather than reserve mobilization from muscle in diploids is suggested by these results. Nutrients derived from ingested food are apparently used for muscle growth in triploids, whereas in diploids those nutrients serve primarily for gonad development. The importance of freshly ingested food for maintenance and growth is suggested because the decline in biochemical components seen in October in both muscle and gonad was paired with a

  9. Features of Vocal Fold Adductor Paralysis and the Management of Posterior Muscle in Thyroplasty.

    PubMed

    Konomi, Ujimoto; Tokashiki, Ryoji; Hiramatsu, Hiroyuki; Motohashi, Ray; Sakurai, Eriko; Toyomura, Fumimasa; Nomoto, Masaki; Kawada, Yuri; Suzuki, Mamoru

    2016-03-01

    To present the pathologic characteristics of unilateral recurrent nerve adductor branch paralysis (AdBP), and to investigate the management of posterior cricoarytenoid (PCA) muscle on the basis of our experience of surgical treatment for AdBP. This is a retrospective review of clinical records Four cases of AdBP, in which surgical treatment was performed, are presented. AdBP shows disorders of vocal fold adduction because of paralysis of the thyroarytenoid and lateral cricoarytenoid muscles. The PCA muscle, dominated by the recurrent nerve PCA muscle branch, does not show paralysis. Thus, this type of partial recurrent nerve paresis retains the abductive function and is difficult to distinguish from arytenoid cartilage dislocation because of their similar endoscopic findings. The features include acute onset, and all cases were idiopathic etiology. Thyroarytenoid muscle paralysis was determined by electromyography and stroboscopic findings. The adduction and abduction of paralytic arytenoids were evaluated from 3 dimensional computed tomography (3DCT). In all cases, surgical treatments were arytenoid adduction combined with thyroplasty. When we adducted the arytenoid cartilage during inspiration, strong resistance was observed. In the two cases where we could cut the PCA muscle sufficiently, the maximum phonation time was improved to ≥30 seconds after surgery, from 2 to 3 seconds preoperatively, providing good postoperative voices. In contrast, in the two cases of insufficient resection, the surgical outcomes were poorer. Because the preoperative voice in AdBP patients is typically very coarse, surgical treatment is needed, as well as ordinary recurrent nerve paralysis. In our experience, adequate PCA muscle resection might be helpful in surgical treatment of AdBP. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  10. A New Option for the Reconstruction of Primary or Recurrent Ischial Pressure Sores: Hamstring-Adductor Magnus Muscle Advancement Flap and Direct Closure.

    PubMed

    Burm, Jin Sik; Hwang, Jungil; Lee, Yung Ki

    2018-04-01

    Owing to the high recurrence rates of ischial pressure sores, surgeons should consider the possibility of future secondary flap surgery during flap selection. The purpose of this article is to present a new surgical option for the reconstruction of primary or recurrent ischial pressure sores using a simple hamstring-adductor magnus advancement flap and direct closure. After horizontal fusiform skin excision, complete bursa excision and ischiectomy were performed. The tenomuscular origin of the adductor magnus and the conjoined tenomuscular origin of the biceps femoris long head and semitendinosus were isolated and completely detached from the inferior border of the ischial tuberosity. They were then advanced in a cephalad direction without detachment of the distal tendon or muscle and securely affixed to the sacrotuberous ligament. The wound was directly closed without further incision or dissection. Twelve ischial pressure sores (6 primary and 6 recurrent; 12 patients) were surgically corrected. The follow-up period was 12 to 65 months. All patients healed successfully without early postoperative complications, such as hematoma, seroma, infection, wound dehiscence, or partial necrosis. Late complications included wound disruption 5 weeks after surgery that spontaneously healed in 1 case and recurrence 3 years later in another case. The new surgical option presented herein, which involves hamstring-adductor magnus advancement flap and direct closure, is a simple and reliable method for providing sufficient muscle bulk to fill the dead space and proper padding to the bone stump while preserving the main vascular perforators and pedicles as well as future surgical options.

  11. Oestrogen status in relation to the early training responses in human thumb adductor muscles.

    PubMed

    Onambele, G N L; Bruce, S A; Woledge, R C

    2006-09-01

    The aims of this study were to identify the mechanisms for the early response to training in women of different oestrogen status and to determine whether any oestrogen and exercise effects on these would be additive. We monitored training (ten 5-s contractions per day for 12 weeks)-induced changes in the size, strength, voluntary activation capacity and index of crossbridge force state (i.e. rapid stretch to isometric torque ratio), in the thumb adductor muscles of postmenopausal [eight who had never used, and 14 who were using, hormone replacement therapy (HRT)] and seven premenopausal eumenorrhoeic women. The contralateral untrained muscle was used as a control. There was a significant effect of oestrogen status on the magnitude of training-induced strength increment, with the non-HRT postmenopausal group exhibiting the greatest benefits (28 +/- 6%, P = 0.024) from training. There were no significant or commensurate changes in either cross-sectional area or voluntary activation capacity. The index of crossbridge force state improved most in the no-HRT group (19 +/- 7%, P < 0.05). Presence, rather than absence of oestrogen, is associated with relatively higher muscle function which limits the potential for any further training-induced increments in muscle performance, as would be expected if the muscle strengthening actions of training and oestrogen share a common, partially saturable physiological pathway. The mechanism that is involved in the early training-induced strength increment in the three differing oestrogen groups cannot be due to increased size or recruitment. It would appear instead that increased motor unit firing frequency is involved.

  12. Vocal fold paralysis: improved adductor recovery by vincristine blockade of posterior cricoarytenoid.

    PubMed

    Paniello, Randal C

    2015-03-01

    A new treatment for acute unilateral vocal-fold paralysis (UVFP) was proposed in which a drug is injected into the posterior cricoarytenoid muscle (PCA) shortly after nerve injury, before the degree of natural recovery is known, to prevent antagonistic synkinetic reinnervation. This concept was tested in a series of canine experiments using vincristine as the blocking agent. Animal experiments. Laryngeal adductor function was measured at baseline and at 6 months following experimental recurrent laryngeal nerve (RLN) injuries, including complete transection, crush injury, and cautery. In the treatment animals, the PCA was injected with vincristine at the time of RLN injury. Adductor function in the vincristine-treated hemilarynges was significantly improved compared with injury-matched noninjected controls (total n = 43). Transection/repair controls recovered 56.1% of original adductor strength; vincristine-treated hemilarynges recovered to 73.1% (P = 0.002). Cautery injuries also improved with vincristine block (60.7% vs. 88.7%; P = 0.031). Crush injuries recovered well even without vincristine (104.8% vs. 111.2%; P = 0.35). These findings support a new paradigm of early, preemptive blockade of the antagonist muscle (PCA) to improve ultimate net adductor strength, which could potentially improve functional recovery in many UVFP patients and avoid the need for medialization procedures. Possible clinical aspects of this new approach are discussed. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  13. Adductor magnus: An EMG investigation into proximal and distal portions and direction specific action.

    PubMed

    Benn, Matthew L; Pizzari, Tania; Rath, Leanne; Tucker, Kylie; Semciw, Adam I

    2018-05-01

    Cadaveric studies indicate that adductor magnus is structurally partitioned into at least two regions. The aim of this study was to investigate the direction-specific actions of proximal and distal portions of adductor magnus, and in doing so determine if these segments have distinct functional roles. Fine-wire EMG electrodes were inserted into two portions of adductor magnus of 12 healthy young adults. Muscle activity was recorded during maximum voluntary isometric contractions (MVICs) across eight tests (hip flexion/extension, internal/external rotation, abduction, and adduction at 0°, 45°, and 90° hip flexion). Median activity within each action (normalized to peak) was compared between segments using repeated measures nonparametric tests (α = 0.05). An effect size (ES = z-score/√sample size) was calculated to determine the magnitude of difference between muscle segments. The relative contribution of each muscle segment differed significantly during internal rotation (P < 0.001; ES = 0.88) and external rotation (P = 0.003, ES = 0.79). The distal portion was most active during extension [median (interquartile range); 100(0)% MVIC)] and internal rotation [58(34)% MVIC]. The proximal portion was most active during extension [100(49)% MVIC] and adduction [59(64)%MVIC], with low level activity during external rotation [15(41)%MVIC]. This study suggests that adductor magnus has at least two functionally unique regions. Differences were most evident during rotation. The different direction-specific actions may imply that each segment performs separate roles in hip stability and movement. These findings may have implications on injury prevention and rehabilitation for adductor-related groin injuries, hamstring strain injury, and hip pathology. Clin. Anat. 31:535-543, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  14. Three dimensional digital reconstruction of the jaw adductor musculature of the extinct marsupial giant Diprotodon optatum

    PubMed Central

    2014-01-01

    The morphology and arrangement of the jaw adductor muscles in vertebrates reflects masticatory style and feeding processes, diet and ecology. However, gross muscle anatomy is rarely preserved in fossils and is, therefore, heavily dependent on reconstructions. An undeformed skull of the extinct marsupial, Diprotodon optatum, recovered from Pleistocene sediments at Bacchus Marsh in Victoria, represents the most complete and best preserved specimen of the species offering a unique opportunity to investigate functional anatomy. Computed tomography (CT) scans and digital reconstructions make it possible to visualise internal cranial anatomy and predict location and morphology of soft tissues, including muscles. This study resulted in a 3D digital reconstruction of the jaw adductor musculature of Diprotodon, revealing that the arrangement of muscles is similar to that of kangaroos and that the muscle actions were predominantly vertical. 3D digital muscle reconstructions provide considerable advantages over 2D reconstructions for the visualisation of the spatial arrangement of the individual muscles and the measurement of muscle properties (length, force vectors and volume). Such digital models can further be used to estimate muscle loads and attachment sites for biomechanical analyses. PMID:25165628

  15. [Effect of hypoxia on glycolysis in the adductor muscle and hepatopancreas of the marine mussel Mytilus galloprovincialis Lmk].

    PubMed

    Ibarguren, I; Villamarín, J A; Barcia, R; Ramos-Martínez, J I

    1989-12-01

    Concentrations of glycolytic intermediates and adenine nucleotides have been estimated in adductor muscle and hepatopancreas from the sea mussel Mytilus galloprovincialis Lmk. after various periods of valve closure. Mass action ratios of enzyme steps involved in the metabolism of these components are compared with their equilibrium constants. This reveals hexokinase, phosphofructokinase, pyruvate kinase and fructose-1,6-bisphosphatase catalyze non-equilibrium reactions. The changes in the concentrations of the glycolytic intermediates and in the rate M.A.R./Keq during hypoxia suggest that the carbon flow after valve closure is first controlled by phophofructokinase, but later on the rate of transformation of phosphoenolyruvate regulates this flow.

  16. Comparative anatomy of the cheek muscles within the Centromochlinae subfamily (Ostariophysi, Siluriformes, Auchenipteridae).

    PubMed

    Sarmento-Soares, Luisa Maria; Porto, Marcovan

    2006-02-01

    Glanidium melanopterum Miranda Ribeiro, a typical representative of the subfamily Centromochlinae (Siluriformes: Auchenipteridae), is herein described myologically and compared to other representative species within the group, Glanidium ribeiroi, G. leopardum, Tatia neivai, T. intermedia, T. creutzbergi, Centromochlus heckelii, and C. existimatus. The structure of seven pairs of striated cephalic muscles was compared anatomically: adductor mandibulae, levator arcus palatini, dilatator operculi, adductor arcus palatini, extensor tentaculi, retractor tentaculi, and levator operculi. We observed broad adductor mandibulae muscles in both Glanidium and Tatia, catfishes with depressed heads and smaller eyes. Similarities between muscles were observed: the presence of a large aponeurotic insertion for the levator arcus palatini muscle; an adductor arcus palatini muscle whose origin spread over the orbitosphenoid, pterosphenoid, and parasphenoid; and the extensor tentaculi muscle broadly attached to the autopalatine. There is no retractor tentaculi muscle in either the Glanidium or Tatia species. On the other hand, in Centromochlus, with forms having large eyes and the tallest head, the adductor mandibulae muscles are slim; there is a thin aponeurotic or muscular insertion for the levator arcus palatini muscle; the adductor arcus palatini muscle originates from a single osseous process, forming a keel on the parasphenoid; the extensor tentaculi muscle is loosely attached to the autopalatine, permitting exclusive rotating and sliding movements between this bone and the maxillary. The retractor tentaculi muscle is connected to the maxilla through a single tendon, so that both extensor and retractor tentaculi muscles contribute to a wide array of movements of the maxillary barbels. A discussion on the differences in autopalatine-maxillary movements among the analyzed groups is given. (c) 2005 Wiley-Liss, Inc.

  17. Comparison of the Effect of Continuous Femoral Nerve Block and Adductor Canal Block after Primary Total Knee Arthroplasty.

    PubMed

    Seo, Seung Suk; Kim, Ok Gul; Seo, Jin Hyeok; Kim, Do Hoon; Kim, Youn Gu; Park, Beyoung Yun

    2017-09-01

    This study aimed to compare the effects of femoral nerve block and adductor canal block on postoperative pain, quadriceps strength, and walking ability after primary total knee arthroplasty. Between November 2014 and February 2015, 60 patients underwent primary total knee arthroplasty. Thirty patients received femoral nerve block and the other 30 received adductor canal block for postoperative pain control. Before spinal anesthesia, the patients received nerve block via a catheter (20 mL 0.75% ropivacaine was administered initially, followed by intermittent bolus injection of 10 mL 0.2% ropivacaine every 6 hours for 3 days). The catheters were maintained in the exact location of nerve block in 24 patients in the femoral nerve block group and in 19 patients in the adductor canal block group. Data collection was carried out from these 43 patients. To evaluate postoperative pain control, the numerical rating scale scores at rest and 45° flexion of the knee were recorded. To evaluate quadriceps strength, manual muscle testing was performed. Walking ability was assessed using the Timed Up and Go test. We also evaluated analgesic consumption and complications of peripheral nerve block. No significant intergroup difference was observed in the numerical rating scale scores at rest and 45° flexion of the knee on postoperative days 1, 2, 3, and 7. The adductor canal block group had significantly greater quadriceps strength than did the femoral nerve block group, as assessed by manual muscle testing on postoperative days 1, 2, and 3. The 2 groups showed no difference in walking ability on postoperative day 1, but on postoperative days 2, 3, walking ability was significantly better in the adductor canal block group than in the femoral nerve block group. No significant intergroup difference was observed in analgesic consumption. The groups showed no difference in postoperative pain control. Adductor canal block was superior to femoral nerve block in preserving quadriceps

  18. Development of mandibular, hyoid and hypobranchial muscles in the zebrafish: homologies and evolution of these muscles within bony fishes and tetrapods

    PubMed Central

    Diogo, Rui; Hinits, Yaniv; Hughes, Simon M

    2008-01-01

    Background During vertebrate head evolution, muscle changes accompanied radical modification of the skeleton. Recent studies have suggested that muscles and their innervation evolve less rapidly than cartilage. The freshwater teleostean zebrafish (Danio rerio) is the most studied actinopterygian model organism, and is sometimes taken to represent osteichthyans as a whole, which include bony fishes and tetrapods. Most work concerning zebrafish cranial muscles has focused on larval stages. We set out to describe the later development of zebrafish head muscles and compare muscle homologies across the Osteichthyes. Results We describe one new muscle and show that the number of mandibular, hyoid and hypobranchial muscles found in four day-old zebrafish larvae is similar to that found in the adult. However, the overall configuration and/or the number of divisions of these muscles change during development. For example, the undivided adductor mandibulae of early larvae gives rise to the adductor mandibulae sections A0, A1-OST, A2 and Aω, and the protractor hyoideus becomes divided into dorsal and ventral portions in adults. There is not always a correspondence between the ontogeny of these muscles in the zebrafish and their evolution within the Osteichthyes. All of the 13 mandibular, hyoid and hypobranchial muscles present in the adult zebrafish are found in at least some other living teleosts, and all except the protractor hyoideus are found in at least some extant non-teleost actinopterygians. Of these muscles, about a quarter (intermandibularis anterior, adductor mandibulae, sternohyoideus) are found in at least some living tetrapods, and a further quarter (levator arcus palatini, adductor arcus palatini, adductor operculi) in at least some extant sarcopterygian fish. Conclusion Although the zebrafish occupies a rather derived phylogenetic position within actinopterygians and even within teleosts, with respect to the mandibular, hyoid and hypobranchial muscles it

  19. Laparoscopic hernia repair with adductor tenotomy for athletic pubalgia: an established procedure for an obscure entity.

    PubMed

    Rossidis, Georgios; Perry, Andrew; Abbas, Husain; Motamarry, Isaac; Lux, Tamara; Farmer, Kevin; Moser, Michael; Clugston, Jay; Caban, Angel; Ben-David, Kfir

    2015-02-01

    Athletic pubalgia is a syndrome of chronic lower abdomen and groin pain that occurs in athletes. It is the direct result of stress and microtears of the rectus abdominis inserting on the pubis from the antagonizing adductor longus muscles, and weakness of the posterior transversalis fascia and bulging of the inguinal floor. Under IRB approval, we conducted a retrospective review of our prospectively competitive athlete patients with athletic pubalgia from 2007 to 2013. A cohort of 54 patients was examined. Mean age was 22.4 years. Most patients were football players (n = 23), triathlon (n = 11), track and field (n = 6), soccer players (n = 5), baseball players (n = 4), swimmers (n = 3), golfer (n = 1), and tennis player (n = 1). Fifty one were males and three were females. All patients failed medical therapy with physiotherapy prior to surgery. 76 % of patients had an MRI performed with 26 % having a right rectus abdominis stripping injury with concomitant strain at the adductor longus musculotendinous junction. 7 % of patients had mild nonspecific edema in the distal bilateral rectus abdominis muscles without evidence of a tear. Twenty patients had no findings on their preoperative MRI, and only one patient was noted to have an inguinal hernia on MRI. All patients underwent laparoscopic totally extraperitoneal inguinal hernia repair with synthetic mesh and ipsilateral adductor longus tenotomy. All patients were able to return to full sports-related activity in 24 days (range 21-28 days). One patient experienced urinary retention and another sustained an adductor brevis hematoma 3 months after completion of rehabilitation and surgical intervention. Mean follow up was 18 months. Athletic pubalgia is a disease with a multifactorial etiology that can be treated surgically by a laparoscopic totally extraperitoneal hernia repair with synthetic mesh accompanied with an ipsilateral adductor longus tenotomy allowing patients to return to sports-related activity early with

  20. Hip adductor activations during run-to-cut maneuvers in compression shorts: Implications for return to sport after groin injury

    PubMed Central

    CHAUDHARI, AJIT M. W.; JAMISON, STEVEN T.; MCNALLY, MICHAEL P.; PAN, XUELIANG; SCHMITT, LAURA C.

    2014-01-01

    Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention or recovery from hip adductor strains. Large eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut maneuvers in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all p<0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts. PMID:24669858

  1. Hip adductor activations during run-to-cut manoeuvres in compression shorts: implications for return to sport after groin injury.

    PubMed

    Chaudhari, Ajit M W; Jamison, Steven T; McNally, Michael P; Pan, Xueliang; Schmitt, Laura C

    2014-01-01

    Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention of or recovery from hip adductor strains. Large, eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography (EMG) of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut manoeuvres in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all P < 0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts.

  2. Lateral Cricoarytenoid Release: Development of a Novel Surgical Treatment Option for Adductor Spasmodic Dysphonia in a Canine Laryngeal Model.

    PubMed

    Park, Andrea M; Paniello, Randal C

    2016-09-01

    To investigate the efficacy of a novel adductor muscle-releasing technique designed to decrease the force of vocal fold adduction, as a potential surgical therapy for patients with adductor spasmodic dysphonia (ADSD). Experimental animal study. A canine laryngeal model was used to assess the acute and sustained efficacy of a lateral cricoarytenoid (LCA) muscle release. A total of 34 canine hemilaryngeal preparations were divided among 7 experimental groups. The LCA muscle was separated from its cricoid cartilage origin via an open, anterior, submucosal approach. The laryngeal adductory pressures (LAP) were assessed pre- and post-muscle release via direct recurrent laryngeal nerve stimulation. Measurements were repeated at 1.5, 3, or 6 months postoperatively. Another study evaluated release of the thyroarytenoid (TA) muscle from its thyroid cartilage origin. Releasing the LCA muscle demonstrated a significant decrease in LAP acutely and was maintained at all 3 time points with the aid of a barrier (P < .05). Without the barrier, the LCA muscle reattached to the cricoid. Acute release of the TA muscle did not significantly decrease the LAP. The proposed LCA release procedure may provide patients with a permanent treatment option for ADSD. However, longer-term studies and human trials are needed. © The Author(s) 2016.

  3. Preseason Adductor Squeeze Strength in 303 Spanish Male Soccer Athletes: A Cross-sectional Study

    PubMed Central

    Esteve, Ernest; Rathleff, Michael Skovdal; Vicens-Bordas, Jordi; Clausen, Mikkel Bek; Hölmich, Per; Sala, Lluís; Thorborg, Kristian

    2018-01-01

    Background: Hip adductor muscle weakness and a history of groin injury both have been identified as strong risk factors for sustaining a new groin injury. Current groin pain and age have been associated with hip adductor strength. These factors could be related, but this has never been investigated. Purpose: To investigate whether soccer athletes with past-season groin pain and with different durations of past-season groin pain had lower preseason hip adductor squeeze strength compared with those without past-season groin pain. We also investigated whether differences in preseason hip adductor squeeze strength in relation to past-season groin pain and duration were influenced by current groin pain and age. Study Design: Cross-sectional study; Level of evidence, 3. Methods: In total, 303 male soccer athletes (mean age, 23 ± 4 years; mean weight, 74.0 ± 7.9 kg; mean height, 178.1 ± 6.3 cm) were included in this study. Self-reported data regarding current groin pain, past-season groin pain, and duration were collected. Hip adductor squeeze strength was obtained using 2 different reliable testing procedures: (1) the short-lever (resistance placed between the knees, feet at the examination bed, and 45° of hip flexion) and (2) the long-lever (resistance placed between the ankles and 0° of hip flexion) squeeze tests. Results: There was no difference between those with (n = 123) and without (n = 180) past-season groin pain for hip adductor squeeze strength when adjusting for current groin pain and age. However, athletes with past-season groin pain lasting longer than 6 weeks (n = 27) showed 11.5% and 15.3% lower values on the short-lever (P = .006) and long-lever (P < .001) hip adductor squeeze strength tests, respectively, compared with those without past-season groin pain. Conclusion: Male soccer athletes with past-season groin pain lasting longer than 6 weeks are likely to begin the next season with a high-risk groin injury profile, including a history of groin

  4. Saphenous and Infrapatellar Nerves at the Adductor Canal: Anatomy and Implications in Regional Anesthesia.

    PubMed

    Anagnostopoulou, Sofia; Anagnostis, George; Saranteas, Theodosios; Mavrogenis, Andreas F; Paraskeuopoulos, Tilemachos

    2016-01-01

    Conflicting data exist regarding the anatomical relationship of the saphenous and infrapatellar nerves at the adductor canal and the location of the superior foramen of the canal. Therefore, the authors performed a cadaveric study to detail the relationship and course of the saphenous and infrapatellar nerves and the level of the superior foramen of the canal. The adductor canal and subsartorial compartment were dissected in 17 human cadavers. The distance between the superior foramen of the canal and the mid-distance (MD) between the base of the patella and the anterior superior iliac crest were measured; the course of the saphenous and infrapatellar nerves and the level of origin of the infrapatellar branch were detailed. In 13 of 17 specimens, the superior foramen of the adductor canal was distal to the MD (mean, 6.5 cm); in the remaining specimens, it was proximal to the MD. In 12 of 17 specimens, the infrapatellar branch exited the canal separately from the saphenous nerve; in the remaining specimens, it originated caudally to the canal. In all dissections, the infrapatellar branch had a constant course in close proximity to the saphenous nerve within the canal and between the sartorious muscle and femoral artery caudally to the canal. Most commonly, the superior foramen of the adductor canal is located caudally to the MD; the infrapatellar branch originates from the saphenous nerve within the canal and has a constant course in close proximity to the saphenous nerve. These observations should be considered for regional anesthesia techniques at the adductor canal. Copyright 2016, SLACK Incorporated.

  5. Zilpaterol hydrochloride affects cellular muscle metabolism and lipid components of ten different muscles in feedlot heifers

    USDA-ARS?s Scientific Manuscript database

    This study determined if zilpaterol hydrochloride (ZH) altered muscle metabolism and lipid components of ten muscles. Crossbred heifers were either supplemented with ZH (n = 9) or not (Control; n = 10). Muscle tissue was collected (adductor femoris, biceps femoris, gluteus medius, infraspinatus, lat...

  6. New insights into dinosaur jaw muscle anatomy.

    PubMed

    Holliday, Casey M

    2009-09-01

    Jaw muscles are key components of the head and critical to testing hypotheses of soft-tissue homology, skull function, and evolution. Dinosaurs evolved an extraordinary diversity of cranial forms adapted to a variety of feeding behaviors. However, disparate evolutionary transformations in head shape and function among dinosaurs and their living relatives, birds and crocodylians, impair straightforward reconstructions of muscles, and other important cephalic soft tissues. This study presents the osteological correlates and inferred soft tissue anatomy of the jaw muscles and relevant neurovasculature in the temporal region of the dinosaur head. Hypotheses of jaw muscle homology were tested across a broad range archosaur and sauropsid taxa to more accurately infer muscle attachments in the adductor chambers of non-avian dinosaurs. Many dinosaurs likely possessed m. levator pterygoideus, a trait shared with lepidosaurs but not extant archosaurs. Several major clades of dinosaurs (e.g., Ornithopoda, Ceratopsidae, Sauropoda) eliminated the epipterygoid, thus impacting interpretations of m. pseudotemporalis profundus. M. pseudotemporalis superficialis most likely attached to the caudoventral surface of the laterosphenoid, a trait shared with extant archosaurs. Although mm. adductor mandibulae externus profundus and medialis likely attached to the caudal half of the dorsotemporal fossa and coronoid process, clear osteological correlates separating the individual bellies are rare. Most dinosaur clades possess osteological correlates indicative of a pterygoideus ventralis muscle that attaches to the lateral surface of the mandible, although the muscle may have extended as far as the jugal in some taxa (e.g., hadrosaurs, tyrannosaurs). The cranial and mandibular attachments of mm adductor mandibulae externus superficialis and adductor mandibulae posterior were consistent across all taxa studied. These new data greatly increase the interpretive resolution of head anatomy in

  7. Elbow joint adductor moment arm as an indicator of forelimb posture in extinct quadrupedal tetrapods

    PubMed Central

    Fujiwara, Shin-ichi; Hutchinson, John R.

    2012-01-01

    Forelimb posture has been a controversial aspect of reconstructing locomotor behaviour in extinct quadrupedal tetrapods. This is partly owing to the qualitative and subjective nature of typical methods, which focus on bony articulations that are often ambiguous and unvalidated postural indicators. Here we outline a new, quantitatively based forelimb posture index that is applicable to a majority of extant tetrapods. By determining the degree of elbow joint adduction/abduction mobility in several tetrapods, the carpal flexor muscles were determined to also play a role as elbow adductors. Such adduction may play a major role during the stance phase in sprawling postures. This role is different from those of upright/sagittal and sloth-like creeping postures, which, respectively, depend more on elbow extensors and flexors. Our measurements of elbow muscle moment arms in 318 extant tetrapod skeletons (Lissamphibia, Synapsida and Reptilia: 33 major clades and 263 genera) revealed that sprawling, sagittal and creeping tetrapods, respectively, emphasize elbow adductor, extensor and flexor muscles. Furthermore, scansorial and non-scansorial taxa, respectively, emphasize flexors and extensors. Thus, forelimb postures of extinct tetrapods can be qualitatively classified based on our quantitative index. Using this method, we find that Triceratops (Ceratopsidae), Anhanguera (Pterosauria) and desmostylian mammals are categorized as upright/sagittally locomoting taxa. PMID:22357261

  8. Clinical application of the right sidelying respiratory left adductor pull back exercise.

    PubMed

    Boyle, Kyndall L

    2013-06-01

    Lumbopelvic-femoral conditions are common and may be associated with asymmetrical musculoskeletal and respiratory impairments and postural mal-alignment called a Left Anterior Interior Chain (AIC) pattern. An inherent pattern of asymmetry involves the trunk/ribs/spine/pelvis/hip joints and includes the tendency to stand on the right leg and shift the center of gravity to the right which may result for example, in a tight left posterior hip capsule, poorly approximated left hip, long/weak left adductors, internal obliques (IO) and transverse abdominus (TA), short/strong/over active paraspinals and muscles on the right anterior outlet (adductors, levator ani and obturator internus), a left rib flare and a decreased respiratory diaphragm zone of apposition (ZOA). A therapeutic exercise technique that can address impairments associated with postural asymmetry may be beneficial in improving function, reducing and/or eliminating pain causation, and improving breathing. The Right Sidelying Left Respiratory Adductor Pull Back is an exercise designed to affect alignment of the lumbopelvic-femoral region by influencing the left posterior ischiofemoral ligament, ZOA and right anterior outlet and left anterior inlet (rectus femoris, sartorius), activating/shortening the left adductors, left IO/TA's and inhibiting/lengthening the paraspinals, bilaterally. The exercise technique is often used by Physical Therapists, Physical Therapist assistants and Athletic Trainers as an initial exercise to positively affect position/alignment of the lumbopelvic-femoral region, referred to as "repositioning," by clinicians who use it. Four published case studies have used similar exercises to address the above impairments associated with a Left AIC pattern and in each 100% improvement in function and pain intensity was described. This particular exercise technique is relatively new and warrants future research.

  9. Osteitis pubis and adductor tendinopathy in athletes: a novel arthroscopic pubic symphysis curettage and adductor reattachment.

    PubMed

    Hopp, Sascha Jörg; Culemann, Ulf; Kelm, Jens; Pohlemann, Tim; Pizanis, Antonius

    2013-07-01

    Various surgical treatment options have been described in athletes with degenerative osteitis pubis who fail to respond to conservative treatment modalities. Although adductor longus tendinopathy often represents an additional pain generator in chronic groin pain associated with osteitis pubis, this has not been acknowledged in the surgical literature, to our knowledge. We present the results of a novel surgical technique for combined degenerative lesions of the pubic symphysis joint and the adjacent adductor longus tendon in a series of athletes with osteitis pubis. During 2009 and 2010, five competitive non-professional soccer players with considerable groin and pubic pain were referred to our clinic, after conservative therapy over a period of at least 12 months had failed. According to our clinical protocol for patients with groin pain, physical examination, pelvic radiographs and arthrography of the pubic symphysis to detect microlesions of the adjacent adductor longus tendons were performed. The patients diagnosed with degenerative osteitis pubis and concomitant lesion of the adductor longus origin were indicated for surgery. Surgery consisted of resection of the degenerative soft and bone tissue and subsequent reattachment with suture anchors. With regard to stability of the symphysis pubis, a two-portal arthroscopic curettage of the degenerative fibrocartilaginous disc tissue was performed. The patients were followed prospectively at medium term with assessment of general pain level (VAS score) and sport activity with pain (NIPPS score) pre- and postoperatively. All patients recovered to full activity sports after an average period of 14.4 weeks. VAS and NIPPS scores markedly improved and overall satisfaction with the postoperative result was high. One intraoperative bleeding occurred, needing revision surgery. None of the patients developed pubic instability due to pubic symphysis curettage in the sequel. This novel surgical technique combines successfully

  10. Recovery of muscle function after deep neuromuscular block by means of diaphragm ultrasonography and adductor of pollicis acceleromyography with comparison of neostigmine vs. sugammadex as reversal drugs: study protocol for a randomized controlled trial.

    PubMed

    Cappellini, Iacopo; Picciafuochi, Fabio; Ostento, Daniele; Danti, Ginevra; De Gaudio, Angelo Raffaele; Adembri, Chiara

    2018-02-21

    The extensive use of neuromuscular blocking agents (NMBAs) during surgical procedures still leads to potential residual paralyzing effects in the postoperative period. Indeed, neuromuscular monitoring in an intra-operative setting is strongly advocated. Acetylcholinesterase inhibitors can reverse muscle block, but their short half-life may lead to residual curarization in the ward, especially when intermediate or long-acting NMBAs have been administered. Sugammadex is the first selective reversal drug for steroidal NMBAs; it has been shown to give full and rapid recovery of muscle strength, thus minimizing the occurrence of residual curarization. Acceleromyography of the adductor pollicis is the gold standard for detecting residual curarization, but it cannot be carried out on conscious patients. Ultrasonography of diaphragm thickness may reveal residual effects of NMBAs in conscious patients. This prospective, double-blind, single-center randomized controlled study will enroll patients (of American Society of Anesthesiologists physical status I-II, aged 18-80 years) who will be scheduled to undergo deep neuromuscular block with rocuronium for ear, nose, or throat surgery. The study's primary objective will be to compare the effects of neostigmine and sugammadex on postoperative residual curarization using two different tools: diaphragm ultrasonography and acceleromyography of the adductor pollicis. Patients will be extubated when the train-of-four ratio is > 0.9. Diaphragm ultrasonography will be used to evaluate the thickening fraction, which is the difference between the end expiratory thickness and the end inspiratory thickness, normalized to the end expiratory thickness. Ultrasonography will be performed before the initiation of general anesthesia, before extubation, and 10 and 30 min after discharging patients from the operating room. The secondary objective will be to compare the incidence of postoperative complications due to residual neuromuscular

  11. Effects of Plyometric Training on Muscle-Activation Strategies and Performance in Female Athletes

    PubMed Central

    Swanik, Kathleen A.; Swanik, C. Buz; Straub, Stephen J.

    2004-01-01

    Objective: To evaluate the effects of plyometric training on muscle-activation strategies and performance of the lower extremity during jumping exercises. Subjects: Twenty healthy National Collegiate Athletic Association Division I female athletes. Design and Setting: A pretest and posttest control group design was used. Experimental subjects performed plyometric exercises 2 times per week for 6 weeks. Measurements: We used surface electromyography to assess preparatory and reactive activity of the vastus medialis and vastus lateralis, medial and lateral hamstrings, and hip abductors and adductors. Vertical jump height and sprint speed were assessed with the VERTEC and infrared timing devices, respectively. Results: Multivariate analyses of variance revealed significant (P < .05) increases in firing of adductor muscles during the preparatory phase, with significant interactions for area, mean, and peak. A Tukey honestly significant difference post hoc analysis revealed significant increases in preparatory adductor area, mean, and peak for experimental group. A significant (P = .037) increase in preparatory adductor-to-abductor muscle coactivation in the experimental group was identified, as well as a trend (P = .053) toward reactive quadriceps-to- hamstring muscle coactivation in the experimental group. Pearson correlation coefficients revealed significant between-groups adaptations in muscle activity patterns pretest to posttest. Although not significant, experimental and control subjects had average increases of 5.8% and 2.0% in vertical jump height, respectively. Conclusions: The increased preparatory adductor activity and abductor-to-adductor coactivation represent preprogrammed motor strategies learned during the plyometric training. These data strongly support the role of hip-musculature activation strategies for dynamic restraint and control of lower extremity alignment at ground contact. Plyometric exercises should be incorporated into the training regimens

  12. Potential use of fatty acid profiles of the adductor muscle of cockles (Cerastoderma edule) for traceability of collection site

    PubMed Central

    Ricardo, Fernando; Pimentel, Tânia; Moreira, Ana S. P.; Rey, Felisa; Coimbra, Manuel A.; Rosário Domingues, M.; Domingues, Pedro; Costa Leal, Miguel; Calado, Ricardo

    2015-01-01

    Geographic traceability of seafood is key for controlling its quality and safeguarding consumers’ interest. The present study assessed if the fatty acid (FA) profile of the adductor muscle (AM) of fresh cockles (Cerastoderma edule) can be used to discriminate the origin of specimens collected in different bivalve capture/production areas legally defined within a coastal lagoon. Results suggest that this biochemical approach holds the potential to trace sampling locations with a spatial resolution <10 Km, even for areas with identical classification for bivalve production. Cockles further away from the inlet, i.e. in areas exposed to a higher saline variation, exhibited lower levels of saturated fatty acids, which are key for stabilizing the bilayer structure of cell membranes, and a higher percentage of polyunsaturated fatty acids, which enhance bilayer fluidity. Results suggest that the structural nature of the lipids present in the AM provides a stable fatty acid signature and holds potential for tracing the origin of bivalves to their capture/production areas. PMID:26084395

  13. CLINICAL APPLICATION OF THE RIGHT SIDELYING RESPIRATORY LEFT ADDUCTOR PULL BACK EXERCISE

    PubMed Central

    2013-01-01

    Problem: Lumbopelvic‐femoral conditions are common and may be associated with asymmetrical musculoskeletal and respiratory impairments and postural mal‐alignment called a Left Anterior Interior Chain (AIC) pattern. An inherent pattern of asymmetry involves the trunk/ribs/spine/pelvis/hip joints and includes the tendency to stand on the right leg and shift the center of gravity to the right which may result for example, in a tight left posterior hip capsule, poorly approximated left hip, long/weak left adductors, internal obliques (IO) and transverse abdominus (TA), short/strong/over active paraspinals and muscles on the right anterior outlet (adductors, levator ani and obturator internus), a left rib flare and a decreased respiratory diaphragm zone of apposition (ZOA). The Solution: A therapeutic exercise technique that can address impairments associated with postural asymmetry may be beneficial in improving function, reducing and/or eliminating pain causation, and improving breathing. The Right Sidelying Left Respiratory Adductor Pull Back is an exercise designed to affect alignment of the lumbopelvic‐femoral region by influencing the left posterior ischiofemoral ligament, ZOA and right anterior outlet and left anterior inlet (rectus femoris, sartorius), activating/shortening the left adductors, left IO/TA's and inhibiting/lengthening the paraspinals, bilaterally. Discussion: The exercise technique is often used by Physical Therapists, Physical Therapist assistants and Athletic Trainers as an initial exercise to positively affect position/alignment of the lumbopelvic‐femoral region, referred to as “repositioning,” by clinicians who use it. Four published case studies have used similar exercises to address the above impairments associated with a Left AIC pattern and in each 100% improvement in function and pain intensity was described. This particular exercise technique is relatively new and warrants future research. PMID:23772350

  14. Evolutionary Trends in the Jaw Adductor Mechanics of Ornithischian Dinosaurs.

    PubMed

    Nabavizadeh, Ali

    2016-03-01

    Jaw mechanics in ornithischian dinosaurs have been widely studied for well over a century. Most of these studies, however, use only one or few taxa within a given ornithischian clade as a model for feeding mechanics across the entire clade. In this study, mandibular mechanical advantages among 52 ornithischian genera spanning all subclades are calculated using 2D lever arm methods. These lever arm calculations estimate the effect of jaw shape and difference in adductor muscle line of action on relative bite forces along the jaw. Results show major instances of overlap between taxa in tooth positions at which there was highest mechanical advantage. A relatively low bite force is seen across the tooth row among thyreophorans (e.g., stegosaurs and ankylosaurs), with variation among taxa. A convergent transition occurs from a more evenly distributed bite force along the jaw in basal ornithopods and basal marginocephalians to a strong distal bite force in hadrosaurids and ceratopsids, respectively. Accordingly, adductor muscle vector angles show repeated trends from a mid-range caudodorsal orientation in basal ornithischians to a decrease in vector angles indicating more caudally oriented jaw movements in derived taxa (e.g., derived thyreophorans, basal ornithopods, lambeosaurines, pachycephalosaurs, and derived ceratopsids). Analyses of hypothetical jaw morphologies were also performed, indicating that both the coronoid process and lowered jaw joint increase moment arm length therefore increasing mechanical advantage of the jaw apparatus. Adaptive trends in craniomandibular anatomy show that ornithischians evolved more complex feeding apparatuses within different clades as well as morphological convergences between clades. © 2016 Wiley Periodicals, Inc.

  15. Myofiber turnover is used to retrofit frog jaw muscles during metamorphosis.

    PubMed

    Alley, K E

    1989-01-01

    Metamorphic reorganization of the head in anuran amphibians entails abrupt restructuring of the jaw complex as larval feeding structures are transformed into their adult configurations. In this morphometric study, light microscopy wa used to analyze the larval maturation and metamorphic transfiguration of the adductor jaw muscles in the leopard frog (Rana pipiens). Larval jaw muscles, first established during embryogenesis, continue to grow by fiber addition until prometamorphosis, stage XII. Thereafter, fiber number remains stable but additional muscle growth continues by hypertrophy of the individual fibers until metamorphic climax. During metamorphic stages XIX-XXIII, a complete involution of all larval myofibers occurs. Simultaneously, within the same muscle beds, a second wave of myogenesis produces myoblasts which are the precursors of adult jaw myofibers. New muscle fibers continue to be added to these muscles well after the completion of metamorphosis; however, the total duration of the postmetamorphic myogenic period has not been defined. These observations provide clear evidence that the entir population of primary myofibers used in larval oral activity disappears from the adductor muscle beds and is replaced by a second wave of myogenesis commencing during climax. These findings indicate that the adductor jaw muscles are prepared for adult feeding by a complicated cellular process that retrofits existing muscle beds with a completely new complement of myofibers.

  16. Anatomy and adaptations of the chewing muscles in Daubentonia (Lemuriformes).

    PubMed

    Perry, Jonathan M G; Macneill, Kristen E; Heckler, Amanda L; Rakotoarisoa, Gilbert; Hartstone-Rose, Adam

    2014-02-01

    The extractive foraging behavior in aye-ayes (Daubentonia madagascariensis) is unique among primates and likely has led to selection for a specialized jaw adductor musculature. Although this musculature has previously been examined in a subadult, until now, no one has reported the fascicle length, weight, and physiological cross-sectional area (PCSA) for these muscles in an adult aye-aye specimen. For the present study, we dissected an adult wild-born aye-aye from the Tsimbazaza Botanical and Zoological Park, Antananarivo, Madagascar. The aye-aye follows the general strepsirrhine pattern in its overall jaw adductor muscle anatomy, but has very large muscles and PCSA relative to body size. Fascicle length is also relatively great, but not nearly as much as in the juvenile aye-aye previously dissected. Perhaps chewing muscle fascicles begin relatively long, but shorten through use and growth as connective tissue sheets expand and allow for pinnation and increased PCSA. Alternately, it may be that aye-ayes develop fascicular adaptation to wide gapes early in ontogeny, only to increase PCSA through later development into adulthood. The functional demands related to their distinctive manner of extractive foraging are likely responsible for the great PCSA in the jaw adductor muscles of the adult aye-aye. It may be that great jaw adductor PCSA in the adult, as compared to the juvenile, is a means of increasing foraging efficiency in the absence of parental assistance. Anat Rec, 297:308-316, 2014. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc.

  17. Vocal Parameters and Self-Perception in Individuals With Adductor Spasmodic Dysphonia.

    PubMed

    Rojas, Gleidy Vannesa E; Ricz, Hilton; Tumas, Vitor; Rodrigues, Guilherme R; Toscano, Patrícia; Aguiar-Ricz, Lílian

    2017-05-01

    The study aimed to compare and correlate perceptual-auditory analysis of vocal parameters and self-perception in individuals with adductor spasmodic dysphonia before and after the application of botulinum toxin. This is a prospective cohort study. Sixteen individuals with a diagnosis of adductor spasmodic dysphonia were submitted to the application of botulinum toxin in the thyroarytenoid muscle, to the recording of a voice signal, and to the Voice Handicap Index (VHI) questionnaire before the application and at two time points after application. Two judges performed a perceptual-auditory analysis of eight vocal parameters with the aid of the Praat software for the visualization of narrow band spectrography, pitch, and intensity contour. Comparison of the vocal parameters before toxin application and on the first return revealed a reduction of oscillation intensity (P = 0.002), voice breaks (P = 0.002), and vocal tremor (P = 0.002). The same parameters increased on the second return. The degree of severity, strained-strangled voice, roughness, breathiness, and asthenia was unchanged. The total score and the emotional domain score of the VHI were reduced on the first return. There was a moderate correlation between the degree of voice severity and the total VHI score before application and on the second return, and a weak correlation on the first return. Perceptual-auditory analysis and self-perception proved to be efficient in the recognition of vocal changes and of the vocal impact on individuals with adductor spasmodic dysphonia under treatment with botulinum toxin, permitting the quantitation of changes along time. Copyright © 2017. Published by Elsevier Inc.

  18. Effectiveness of spinal anesthesia combined with obturator nerve blockade in preventing adductor muscle contraction during transurethral resection of bladder tumor

    PubMed Central

    Alavi, Cyrus Emir; Asgari, Seyed Alaeddin; Falahatkar, Siavash; Rimaz, Siamak; Naghipour, Mohammadreza; Khoshrang, Hossein; Jafari, Mehdi; Herfeh, Nadia

    2017-01-01

    Objective To determine whether spinal anesthesia combined with obturator nerve blockade (SOB) is effective in preventing obturator nerve stimulation, jerking and bladder perforation during transurethral resection of bladder tumor (TURBT). Material and methods In this clinical trial, 30 patients were randomly divided into two groups: spinal anesthesia (SA) and SOB. In SA group, 2.5 cc of 0.5% bupivacaine was injected intrathecally using a 25-gauge spinal needle and in SOB after spinal anesthesia, a classic obturator nerve blockade was performed by using nerve stimulation technique. Results There was a statistically significant difference between jerking in both groups (p=0.006). During the TURBT, surgeon satisfaction was significantly higher in SOB group compared to SA group (p=0.006). There was no significant correlation between sex, patient age and location of bladder tumor between the groups (p>0.05). Conclusion Obturator nerve blockade by using 15 cc lidocaine 1% is effective in preventing adductor muscle spasms during TURBT. PMID:29201516

  19. [Acoustic characteristics of adductor spasmodic dysphonia].

    PubMed

    Yang, Yang; Wang, Li-Ping

    2008-06-01

    To explore the acoustic characteristics of adductor spasmodic dysphonia. The acoustic characteristics, including acoustic signal of recorded voice, three-dimensional sonogram patterns and subjective assessment of voice, between 10 patients (7 women, 3 men) with adductor spasmodic dysphonia and 10 healthy volunteers (5 women, 5 men), were compared. The main clinical manifestation of adductor spasmodic dysphonia included the disorders of sound quality, rhyme and fluency. It demonstrated the tension dysphonia when reading, acoustic jitter, momentary fluctuation of frequency and volume, voice squeezing, interruption, voice prolongation, and losing normal chime. Among 10 patients, there were 1 mild dysphonia (abnormal syllable number < 25%), 6 moderate dysphonia (abnormal syllable number 25%-49%), 1 severe dysphonia (abnormal syllable number 50%-74%) and 2 extremely severe dysphonia (abnormal syllable number > or = 75%). The average reading time in 10 patients was 49 s, with reading time extension and aphasia area interruption in acoustic signals, whereas the average reading time in health control group was 30 s, without voice interruption. The aphasia ratio averaged 42%. The respective symptom syllable in different patients demonstrated in the three-dimensional sonogram. There were voice onset time prolongation, irregular, interrupted and even absent vowel formants. The consonant of symptom syllables displayed absence or prolongation of friction murmur in the block-friction murmur occasionally. The acoustic characteristics of adductor spasmodic dysphonia is the disorders of sound quality, rhyme and fluency. The three-dimensional sonogram of the symptom syllables show distinctive changes of proportional vowels or consonant phonemes.

  20. Changes in Adductor Strength After Competition in Academy Rugby Union Players.

    PubMed

    Roe, Gregory A B; Phibbs, Padraic J; Till, Kevin; Jones, Ben L; Read, Dale B; Weakley, Jonathon J; Darrall-Jones, Joshua D

    2016-02-01

    This study determined the magnitude of change in adductor strength after a competitive match in academy rugby union players and examined the relationship between locomotive demands of match-play and changes in postmatch adductor strength. A within-subject repeated measures design was used. Fourteen academy rugby union players (age, 17.4 ± 0.8 years; height, 182.7 ± 7.6 cm; body mass, 86.2 ± 11.6 kg) participated in the study. Each player performed 3 maximal adductor squeezes at 45° of hip flexion before and immediately, 24, 48, and 72 hours postmatch. Global positioning system was used to assess locomotive demands of match-play. Trivial decreases in adductor squeeze scores occurred immediately (-1.3 ± 2.5%; effect size [ES] = -0.11 ± 0.21; likely, 74%) and 24 hours after match (-0.7 ± 3%; ES = -0.06 ± 0.25; likely, 78%), whereas a small but substantial increase occurred at 48 hours (3.8 ± 1.9%; ES = 0.32 ± 0.16; likely, 89%) before reducing to trivial at 72 hours after match (3.1 ± 2.2%; ES = 0.26 ± 0.18; possibly, 72%). Large individual variation in adductor strength was observed at all time points. The relationship between changes in adductor strength and distance covered at sprinting speed (VO2max ≥ 81%) was large immediately postmatch (p = 0.056, r = -0.521), moderate at 24 hours (p = 0.094, r = -0.465), and very large at 48 hours postmatch (p = 0.005, r = -0.707). Players who cover greater distances sprinting may suffer greater adductor fatigue in the first 48 hours after competition. The assessment of adductor strength using the adductor squeeze test should be considered postmatch to identify players who may require additional rest before returning to field-based training.

  1. Distribution of Injectate and Sensory-Motor Blockade After Adductor Canal Block.

    PubMed

    Gautier, Philippe E; Hadzic, Admir; Lecoq, Jean-Pierre; Brichant, Jean Francois; Kuroda, Maxine M; Vandepitte, Catherine

    2016-01-01

    The analgesic efficacy reported for the adductor canal block may be related to the spread of local anesthetic outside the adductor canal. Fifteen patients undergoing knee surgery received ultrasound-guided injections of local anesthetic at the level of the adductor hiatus. Sensory-motor block and spread of contrast solution were assessed. Sensation was rated as "markedly diminished" or "absent" in the saphenous nerve distribution and "slightly diminished" in the sciatic nerve territory without motor deficits. Contrast solution was found in the popliteal fossa. The spread of injectate to the popliteal fossa may contribute to the analgesic efficacy of adductor canal block.

  2. Five myofibrillar lesion types in eccentrically challenged, unloaded rat adductor longus muscle--a test model

    NASA Technical Reports Server (NTRS)

    Thompson, J. L.; Balog, E. M.; Fitts, R. H.; Riley, D. A.

    1999-01-01

    Sarcomere disruptions are observed in the adductor longus (AL) muscles following voluntary reloading of spaceflown and hindlimb suspension unloaded (HSU) rat, which resemble lesions in eccentrically challenged muscle. We devised and tested an eccentric contraction (ECCON) test system for the 14-day HSU rat AL. Six to 7 hours following ECCON, ALs were fixed to allow immunostaining and electron microscopy (EM). Toluidine blue-stained histology semithin sections were screened for lesion density (#/mm2). Serial semithin sections from the ECCON group were characterized for myosin immunointensity of lesions. Five myofibrillar lesion types were identified in histological semithin sections: focal contractions; wide A-bands; opaque areas; missing A-bands; and hyperstretched sarcomeres. Lesion density by type was greater for ECCON than NonECCON ALs (P< or =0.05; focal contractions and opaque regions). Lesion density (#-of-all-five-types/mm2) was significantly different (ECCON: 23.91+/-10.58 vs. NonECCON: 5.48+/-1.28, P< or =0.05; ECCON vs. SHAM: 0.00+/-0.00; P< or = 0.025). PostECCON optimal tension decreased (Poi-drop, 17.84+/-4.22%) and was correlated to lesion density (R2=0.596), but prestretch tension demonstrated the highest correlation with lesion density (R2=0.994). In lesions, the darkly staining A-band lost the normally organized thick filament alignment to differing degrees across the different lesion types. Ranking the five lesion types by a measure of lesion length deformation (hypercontracted to hyperstretched) at the light microscopy level, related to the severity of thick filament registry loss across the lesion types at the electron microscopic level. This ranking suggested that the five lesion types seen in semithin sections at the light level represented a lesion progression sequence and paralleled myosin immunostaining loss as the distorted A-band filaments spread across the hyperlengthening lesion types. Lesion ultrastructure indicated damage involved

  3. Vocal aging and adductor spasmodic dysphonia: Response to botulinum toxin injection

    PubMed Central

    Cannito, Michael P; Kahane, Joel C; Chorna, Lesya

    2008-01-01

    Aging of the larynx is characterized by involutional changes which alter its biomechanical and neural properties and create a biological environment that is different from younger counterparts. Illustrative anatomical examples are presented. This natural, non-disease process appears to set conditions which may influence the effectiveness of botulinum toxin injection and our expectations for its success. Adductor spasmodic dysphonia, a type of laryngeal dystonia, is typically treated using botulinum toxin injections of the vocal folds in order to suppress adductory muscle spasms which are disruptive to production of speech and voice. A few studies have suggested diminished response to treatment in older patients with adductor spasmodic dysphonia. This retrospective study provides a reanalysis of existing pre-to-post treatment data as function of age. Perceptual judgments of speech produced by 42 patients with ADSD were made by two panels of professional listeners with expertise in voice or fluency of speech. Results demonstrate a markedly reduced positive response to botulinum toxin treatment in the older patients. Perceptual findings are further elucidated by means of acoustic spectrography. Literature on vocal aging is reviewed to provide a specific set of biological mechanisms that best account for the observed interaction of botulinum toxin treatment with advancing age. PMID:18488884

  4. Vocal aging and adductor spasmodic dysphonia: response to botulinum toxin injection.

    PubMed

    Cannito, Michael P; Kahane, Joel C; Chorna, Lesya

    2008-01-01

    Aging of the larynx is characterized by involutional changes which alter its biomechanical and neural properties and create a biological environment that is different from younger counterparts. Illustrative anatomical examples are presented. This natural, non-disease process appears to set conditions which may influence the effectiveness of botulinum toxin injection and our expectations for its success. Adductor spasmodic dysphonia, a type of laryngeal dystonia, is typically treated using botulinum toxin injections of the vocal folds in order to suppress adductory muscle spasms which are disruptive to production of speech and voice. A few studies have suggested diminished response to treatment in older patients with adductor spasmodic dysphonia. This retrospective study provides a reanalysis of existing pre-to-post treatment data as function of age. Perceptual judgments of speech produced by 42 patients with ADSD were made by two panels of professional listeners with expertise in voice or fluency of speech. Results demonstrate a markedly reduced positive response to botulinum toxin treatment in the older patients. Perceptual findings are further elucidated by means of acoustic spectrography. Literature on vocal aging is reviewed to provide a specific set of biological mechanisms that best account for the observed interaction of botulinum toxin treatment with advancing age.

  5. Gender differences in onabotulinum toxin A dosing for adductor spasmodic dysphonia.

    PubMed

    Lerner, Michael Z; Lerner, Benjamin A; Patel, Amit A; Blitzer, Andrew

    2017-05-01

    The objective of this study was to determine the influence of gender on onabotulinum toxin A dosing for the treatment of adductor spasmodic dysphonia symptoms. Retrospective review. A chart review of the senior author's database of botulinum toxin injections was performed. Patients diagnosed with adductor spasmodic dysphonia who received onabotulinum toxin A (BoNTA) injections to the thyroarytenoid muscle for at least 5 years were included for study. Patients who received alternate formulations of botulinum toxin (Myobloc, Dysport, or Xeomin) and patients with alternate diagnoses, such as abductor spasmodic dysphonia, tremor, and oromandibular dystonia, were excluded. The average BoNTA dose was calculated for each patient and statistical analysis was performed comparing the male and female groups. A total of 201 patients (52 males and 149 females) met inclusion criteria. The average follow-up times for the male and female groups were 10.2 ± 3.6 and 11.1 ± 4 years, respectively. The average BoNTA doses for the male and female groups were 0.6 ± 0.42 U and 1.3 ± 1.1 U, respectively. Statistical analysis was performed using an independent samples two-tailed t test yielding a P value of .0000000002. A large effect size was noted with Cohen's d = 0.85. The data from this retrospective chart review reveal a statistically and clinically significant correlation between female gender and higher average BoNTA dose for symptom control in adductor spasmodic dysphonia. Explanations for this observation are speculative and include a possible inverse relationship between optimal BoNTA dose and vocal fold mass and possibly greater neutralizing antibody formation among female patients. 4. Laryngoscope, 127:1131-1134, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  6. Automated acoustic analysis of task dependency in adductor spasmodic dysphonia versus muscle tension dysphonia.

    PubMed

    Roy, Nelson; Mazin, Alqhazo; Awan, Shaheen N

    2014-03-01

    Distinguishing muscle tension dysphonia (MTD) from adductor spasmodic dysphonia (ADSD) can be difficult. Unlike MTD, ADSD is described as "task-dependent," implying that dysphonia severity varies depending upon the demands of the vocal task, with connected speech thought to be more symptomatic than sustained vowels. This study used an acoustic index of dysphonia severity (i.e., the Cepstral Spectral Index of Dysphonia [CSID]) to: 1) assess the value of "task dependency" to distinguish ADSD from MTD, and to 2) examine associations between the CSID and listener ratings. Case-Control Study. CSID estimates of dysphonia severity for connected speech and sustained vowels of patients with ADSD (n = 36) and MTD (n = 45) were compared. The diagnostic precision of task dependency (as evidenced by differences in CSID-estimated dysphonia severity between connected speech and sustained vowels) was examined. In ADSD, CSID-estimated severity for connected speech (M = 39. 2, SD = 22.0) was significantly worse than for sustained vowels (M = 29.3, SD = 21.9), [P = .020]. Whereas in MTD, no significant difference in CSID-estimated severity was observed between connected speech (M = 55.1, SD = 23.8) and sustained vowels (M = 50.0, SD = 27.4), [P = .177]. CSID evidence of task dependency correctly identified 66.7% of ADSD cases (sensitivity) and 64.4% of MTD cases (specificity). CSID and listener ratings were significantly correlated. Task dependency in ADSD, as revealed by differences in acoustically-derived estimates of dysphonia severity between connected speech and sustained vowel production, is a potentially valuable diagnostic marker. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  7. Relationship between lower extremity isometric muscle strength and standing balance in patients with multiple sclerosis.

    PubMed

    Citaker, Seyit; Guclu-Gunduz, Arzu; Yazici, Gokhan; Bayraktar, Deniz; Nazliel, Bijen; Irkec, Ceyla

    2013-01-01

    Muscle strength and standing balance decrease in patients with Multiple Sclerosis (MS). The aim of the present study was to investigate the relationship between the lower extremity isometric muscle strength and standing balance in patients with MS. Forty-seven patients with MS and 10 healthy volunteers were included. Neurological disability level was assessed using Expanded Disability Status Scale (EDSS). Isometric strength of seven lower extremity muscles (hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor) was assessed using hand-held dynamometer. Duration of static one-leg standing balance was measured using digital chronometer. Hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor isometric muscle strength, and duration of one-leg standing balance were decreased in patients with MS when compared with controls (p < 0.05). All assessed lower extremity isometric muscle strength and EDSS level was related duration of one-leg standing balance in patients with MS. All assessed lower extremity isometric muscle strength (except ankle dorsal flexor) was related with EDSS. Hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor isometric muscle strength decreases in ambulatory MS patients. Lower extremity muscle weakness and neurological disability level are related with imbalance in MS population. Hip and knee region muscles weakness increases the neurological disability level. For the better balance and decrease neurological disability level whole lower extremity muscle strengthening should be included in rehabilitation programs.

  8. Homology of the jaw muscles in lizards and snakes-a solution from a comparative gnathostome approach.

    PubMed

    Johnston, Peter

    2014-03-01

    Homology or shared evolutionary origin of jaw adductor muscles in lizards and snakes has been difficult to establish, although snakes clearly arose within the lizard radiation. Lizards typically have temporal adductors layered lateral to medial, and in snakes the muscles are arranged in a rostral to caudal pattern. Recent work has suggested that the jaw adductor group in gnathostomes is arranged as a folded sheet; when this theory is applied to snakes, homology with lizard morphology can be seen. This conclusion revisits the work of S.B. McDowell, J Herpetol 1986; 20:353-407, who proposed that homology involves identity of m. levator anguli oris and the loss of m. adductor mandibulae externus profundus, at least in "advanced" (colubroid) snakes. Here I advance the folded sheet hypothesis across the whole snake tree using new and literature data, and provide a solution to this homology problem. Copyright © 2014 Wiley Periodicals, Inc.

  9. Effect of hindlimb suspension and clenbuterol treatment on polyamine levels in skeletal muscle

    NASA Technical Reports Server (NTRS)

    Abukhalaf, Imad K.; von Deutsch, Daniel A.; Wineski, Lawrence E.; Silvestrov, Natalia A.; Abera, Saare A.; Sahlu, Sinafikish W.; Potter, David E.; Thierry-Palmer, M. (Principal Investigator)

    2002-01-01

    Polyamines are unbiquitous, naturally occurring small aliphatic, polycationic, endogenous compounds. They are involved in many cellular processes and may serve as secondary or tertiary messengers to hormonal regulation. The relationship of polyamines and skeletal muscle mass of adductor longus, extensor digitorum longus, and gastrocnemius under unloading (hindlimb suspension) conditions was investigated. Unloading significantly affected skeletal muscle polyamine levels in a fiber-type-specific fashion. Under loading conditions, clenbuterol treatment increased all polyamine levels, whereas under unloading conditions, only the spermidine levels were consistently increased. Unloading attenuated the anabolic effects of clenbuterol in predominately slow-twitch muscles (adductor longus), but had little impact on clenbuterol's action as a countermeasure in fast- twitch muscles such as the extensor digitorum longus. Spermidine appeared to be the primary polyamine involved in skeletal muscle atrophy/hypertrophy. Copyright 2002 S. Karger AG, Basel.

  10. Influence of muscle groups' activation on proximal femoral growth tendency.

    PubMed

    Yadav, Priti; Shefelbine, Sandra J; Pontén, Eva; Gutierrez-Farewik, Elena M

    2017-12-01

    Muscle and joint contact force influence stresses at the proximal growth plate of the femur and thus bone growth, affecting the neck shaft angle (NSA) and femoral anteversion (FA). This study aims to illustrate how different muscle groups' activation during gait affects NSA and FA development in able-bodied children. Subject-specific femur models were developed for three able-bodied children (ages 6, 7, and 11 years) using magnetic resonance images. Contributions of different muscle groups-hip flexors, hip extensors, hip adductors, hip abductors, and knee extensors-to overall hip contact force were computed. Specific growth rate for the growth plate was computed, and the growth was simulated in the principal stress direction at each element in the growth front. The predicted growth indicated decreased NSA and FA (of about [Formula: see text] over a four-month period) for able-bodied children. Hip abductors contributed the most, and hip adductors, the least, to growth rate. All muscles groups contributed to a decrease in predicted NSA ([Formula: see text]0.01[Formula: see text]-0.04[Formula: see text] and FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]), except hip extensors and hip adductors, which showed a tendency to increase the FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]). Understanding influences of different muscle groups on long bone growth tendency can help in treatment planning for growing children with affected gait.

  11. Quantifying the aging response and nutrient composition for muscles of the beef round.

    PubMed

    Dixon, C L; Woerner, D R; Tokach, R J; Chapman, P L; Engle, T E; Tatum, J D; Belk, K E

    2012-03-01

    The objective of this study was to determine the optimal postmortem aging period and nutrient composition for Beef Value Cuts of the round. Forty USDA Select and 40 Premium USDA Choice beef carcasses were selected from a commercial beef packing plant in Colorado over a 12-wk period. The bottom and inside rounds were collected from both sides of each carcass for further fabrication into the following muscles: adductor, gastrocnemius, gracilis, pectineus, and superficial digital flexor. Each pair of muscles was cut into 7 steaks and randomly assigned to 1 of the following aging periods: 2, 4, 6, 10, 14, 21, and 28 d, and placed in refrigerated storage (2°C, never frozen). Upon completion of the designated aging period, steaks were removed from storage, cooked to a peak internal temperature of 72°C, and evaluated using Warner-Bratzler shear force (WBSF). A 2-way interaction was detected (P < 0.05) between individual muscle and postmortem aging period. The WBSF of all muscles except the superficial digital flexor decreased with increased time of postmortem aging. Quality grade did not affect (P > 0.05) WBSF values for the adductor, gastrocnemius, pectineus, and superficial digital flexor muscles. Exponential decay models were used to predict the change in WBSF from 2 to 28 d postmortem (aging response). The adductor, gastrocnemius, Select gracilis, Premium Choice gracilis, and pectineus required 21, 14, 23, 23, and 25 d, respectively, to complete the majority of the aging response. To determine the nutrient composition of the adductor, gastrocnemius, gracilis, pectineus, semimembranosus, and superficial digital flexor, bottom and inside rounds were collected from 10 USDA Select and 10 Premium USDA Choice carcasses and fabricated into the respective muscles, cut into 2.54-cm cubes, frozen (-20°C), and then homogenized. The adductor, gracilis, pectineus, semimembranosus, and superficial digital flexor were analyzed for DM, moisture, CP, and ash percentages. All

  12. Minithyrotomy with radiofrequency-induced thermotherapy for the treatment of adductor spasmodic dysphonia.

    PubMed

    Desai, Shaun C; Park, Andrea M; Chernock, Rebecca D; Paniello, Randal C

    2016-10-01

    A simple, safe and effective surgical alternative for treating adductor spasmodic dysphonia (ADSD) would appeal to many patients. This study evaluates a new option, using radiofrequency-induced thermotherapy (RFITT) of the thyroarytenoid muscle (TA) via the minithyrotomy approach to reduce the force of adduction. Fifteen dogs were used. In part 1, the optimal RFITT power settings, exposure time, probe location, and number of passes were determined. Part 2 compared laryngeal adductor pressures (LAPs) at baseline; immediately postintervention; and at 1, 3, or 6 months postintervention. Interventions included RFITT via the transcervical minithyrotomy approach (n = 15), transoral RFITT (n = 3), botulinum toxin (Botox) injection (n = 3), or no-intervention controls (n = 3). Postintervention induced phonation and histologic analyses were performed as well. In the minithyrotomy RFITT group, the mean LAP was 30.3% of baseline immediately posttreatment. At 1, 3, and 6 months postoperatively, the mean LAPs were 24.9%, 44.8%, and 43.5%, respectively. Transoral RFITT reduced LAP to 56.6% of baseline immediately posttreatment, but returned to normal in the 1 and 3 month animals. The Botox injections dropped the LAP to 57% of baseline at 1 month, but returned to normal at 3 months. Mucosal waves, based on induced phonation stroboscopy, were present at the terminal date in all animals. Thirteen of 15 transcervical RFITT preparations (87%) showed no injury to the lamina propria, whereas 80% showed evidence of TA muscle atrophy and fibrosis. Minithyrotomy RFITT is a feasible technique that shows encouraging long-term results for the potential treatment of patients with ADSD. N/A. Laryngoscope, 126:2325-2329, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  13. Effects of type II thyroplasty on adductor spasmodic dysphonia.

    PubMed

    Sanuki, Tetsuji; Yumoto, Eiji; Minoda, Ryosei; Kodama, Narihiro

    2010-04-01

    Type II thyroplasty, or laryngeal framework surgery, is based on the hypothesis that the effect of adductor spasmodic dysphonia (AdSD) on the voice is due to excessively tight closure of the glottis, hampering phonation. Most of the previous, partially effective treatments have aimed to relieve this tight closure, including recurrent laryngeal nerve section or avulsion, extirpation of the adductor muscle, and botulinum toxin injection, which is currently the most popular. The aim of this study was to assess the effects of type II thyroplasty on aerodynamic and acoustic findings in patients with AdSD. Case series. University hospital. Ten patients with AdSD underwent type II thyroplasty between August 2006 and December 2008. Aerodynamic and acoustic analyses were performed prior to and six months after surgery. Mean flow rates (MFRs) and voice efficiency were evaluated with a phonation analyzer. Jitter, shimmer, the harmonics-to-noise ratio (HNR), standard deviation of the fundamental frequency (SDF0), and degree of voice breaks (DVB) were measured from each subject's longest sustained phonation sample of the vowel /a/. Voice efficiency improved significantly after surgery. No significant difference was found in the MFRs between before and after surgery. Jitter, shimmer, HNR, SDF0, and DVB improved significantly after surgery. Treatment of AdSD with type II thyroplasty significantly improved aerodynamic and acoustic findings. The results of this study suggest that type II thyroplasty provides relief from voice strangulation in patients with AdSD. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  14. Region-Specific Responses of Adductor Longus Muscle to Gravitational Load-Dependent Activity in Wistar Hannover Rats

    PubMed Central

    Ohira, Takashi; Terada, Masahiro; Kawano, Fuminori; Nakai, Naoya; Ogura, Akihiko; Ohira, Yoshinobu

    2011-01-01

    Response of adductor longus (AL) muscle to gravitational unloading and reloading was studied. Male Wistar Hannover rats (5-wk old) were hindlimb-unloaded for 16 days with or without 16-day ambulation recovery. The electromyogram (EMG) activity in AL decreased after acute unloading, but that in the rostral region was even elevated during continuous unloading. The EMG levels in the caudal region gradually increased up to 6th day, but decreased again. Approximately 97% of fibers in the caudal region were pure type I at the beginning of experiment. Mean percentage of type I fibers in the rostral region was 61% and that of type I+II and II fiber was 14 and 25%, respectively. The percent type I fibers decreased and de novo appearance of type I+II was noted after unloading. But the fiber phenotype in caudal, not rostral and middle, region was normalized after 16-day ambulation. Pronounced atrophy after unloading and re-growth following ambulation was noted in type I fibers of the caudal region. Sarcomere length in the caudal region was passively shortened during unloading, but that in the rostral region was unchanged or even stretched slightly. Growth-associated increase of myonuclear number seen in the caudal region of control rats was inhibited by unloading. Number of mitotic active satellite cells decreased after unloading only in the caudal region. It was indicated that the responses of fiber properties in AL to unloading and reloading were closely related to the region-specific neural and mechanical activities, being the caudal region more responsive. PMID:21731645

  15. Contractility and supersensitivity to adrenaline in dystrophic muscle.

    PubMed Central

    Takamori, M

    1975-01-01

    In the adductor pollicis muscle of patients with limb-girdle and facioscapulohumeral muscular dystrophies and possible carriers of Duchenne type muscular dystrophy, abnormal active state properties were found at the time when there was no alteration of needle electromyography and evoked muscle action potentials. Adrenaline induced a marked reduction of incomplete tetanus via beta receptors without change in neuromuscular transmission. PMID:1151415

  16. Comparative jaw muscle anatomy in kangaroos, wallabies, and rat-kangaroos (marsupialia: macropodoidea).

    PubMed

    Warburton, Natalie Marina

    2009-06-01

    The jaw muscles were studied in seven genera of macropodoid marsupials with diets ranging from mainly fungi in Potorous to grass in Macropus. Relative size, attachments, and lamination within the jaw adductor muscles varied between macropodoid species. Among macropodine species, the jaw adductor muscle proportions vary with feeding type. The relative mass of the masseter is roughly consistent, but grazers and mixed-feeders (Macropus and Lagostrophus) had relatively larger medial pterygoids and smaller temporalis muscles than the browsers (Dendrolagus, Dorcopsulus, and Setonix). Grazing macropods show similar jaw muscle proportions to "ungulate-grinding" type placental mammals. The internal architecture of the jaw muscles also varies between grazing and browsing macropods, most significantly, the anatomy of the medial pterygoid muscle. Potoroines have distinctly different jaw muscle proportions to macropodines. The masseter muscle group, in particular, the superficial masseter is enlarged, while the temporalis group is relatively reduced. Lagostrophus fasciatus is anatomically distinct from other macropods with respect to its masticatory muscle anatomy, including enlarged superficial medial pterygoid and deep temporalis muscles, an anteriorly inflected masseteric process, and the shape of the mandibular condyle. The enlarged triangular pterygoid process of the sphenoid bone, in particular, is distinctive of Lagsotrophus. (c) 2009 Wiley-Liss, Inc.

  17. Unilateral versus bilateral thyroarytenoid Botulinum toxin injections in adductor spasmodic dysphonia: a prospective study

    PubMed Central

    Upile, Tahwinder; Elmiyeh, Behrad; Jerjes, Waseem; Prasad, Vyas; Kafas, Panagiotis; Abiola, Jesuloba; Youl, Bryan; Epstein, Ruth; Hopper, Colin; Sudhoff, Holger; Rubin, John

    2009-01-01

    Objectives In this preliminary prospective study, we compared unilateral and bilateral thyroarytenoid muscle injections of Botulinum toxin (Dysport) in 31 patients with adductor spasmodic dysphonia, who had undergone more than 5 consecutive Dysport injections (either unilateral or bilateral) and had completed 5 concomitant self-rated efficacy and complication scores questionnaires related to the previous injections. We also developed a Neurophysiological Scoring (NPS) system which has utility in the treatment administration. Method and materials Data were gathered prospectively on voice improvement (self-rated 6 point scale), length of response and duration of complications (breathiness, cough, dysphagia and total voice loss). Injections were performed under electromyography (EMG) guidance. NPS scale was used to describe the EMG response. Dose and unilateral/bilateral injections were determined by clinical judgment based on previous response. Time intervals between injections were patient driven. Results Low dose unilateral Dysport injection was associated with no significant difference in the patient's outcome in terms of duration of action, voice score (VS) and complication rate when compared to bilateral injections. Unilateral injections were not associated with any post treatment total voice loss unlike the bilateral injections. Conclusion Unilateral low dose Dysport injections are recommended in the treatment of adductor spasmodic dysphonia. PMID:19852852

  18. Do Australian Football players have sensitive groins? Players with current groin pain exhibit mechanical hyperalgesia of the adductor tendon.

    PubMed

    Drew, Michael K; Lovell, Gregory; Palsson, Thorvaldur S; Chiarelli, Pauline E; Osmotherly, Peter G

    2016-10-01

    This is the first study to evaluate the mechanical sensitivity, clinical classifications and prevalence of groin pain in Australian football players. Case-control. Professional (n=66) and semi-professional (n=9) Australian football players with and without current or previous groin injuries were recruited. Diagnoses were mapped to the Doha Agreement taxonomy. Point and career prevalence of groin pain was calculated. Pressure pain thresholds (PPTs) were assessed at regional and distant sites using handheld pressure algometry across four sites bilaterally (adductor longus tendon, pubic bone, rectus femoris, tibialis anterior muscle). To assess the relationship between current groin pain and fixed effects of hyperalgesia of each site and a history of groin pain, a mixed-effect logistic regression model was utilised. Receiver Operator Characteristic (ROC) curve were determined for the model. Point prevalence of groin pain in the preseason was 21.9% with a career prevalence of 44.8%. Adductor-related groin pain was the most prevalent classification in the pre-season period. Hyperalgesia was observed in the adductor longus tendon site in athletes with current groin pain (OR=16.27, 95% CI 1.86 to 142.02). The ROC area under the curve of the regression model was fair (AUC=0.76, 95% CI 0.54 to 0.83). Prevalence data indicates that groin pain is a larger issue than published incidence rates imply. Adductor-related groin pain is the most common diagnosis in pre-season in this population. This study has shown that hyperalgesia exists in Australian football players experiencing groin pain indicating the value of assessing mechanical pain sensitivity as a component of the clinical assessment. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. Differences in botulinum toxin dosing between patients with adductor spasmodic dysphonia and essential voice tremor.

    PubMed

    Orbelo, Diana M; Duffy, Joseph R; Hughes Borst, Becky J; Ekbom, Dale; Maragos, Nicolas E

    2014-01-01

    To explore possible dose differences in average botulinum toxin (BTX) given to patients with adductor spasmodic dysphonia (ADSD) compared with patients with essential voice tremor (EVT). A retrospective study compared the average BTX dose injected in equal doses to the thyroarytenoid (TA) muscles of 51 patients with ADSD with 52 patients with EVT. Those with ADSD received significantly higher total doses (6.80 ± 2.79 units) compared with those with EVT (5.02 ± 1.65 units). Dose at time of first injection, age at time of first injection, gender, year of first injection, and average time between injections were included in multivariate analysis but did not interact with total average dose findings. Patients with ADSD may need relatively higher doses of BTX injections to bilateral TA muscles compared with patients with EVT. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  20. Muscle MRI of classic infantile pompe patients: Fatty substitution and edema-like changes.

    PubMed

    Pichiecchio, Anna; Rossi, Marta; Cinnante, Claudia; Colafati, Giovanna Stefania; De Icco, Roberto; Parini, Rossella; Menni, Francesca; Furlan, Francesca; Burlina, Alberto; Sacchini, Michele; Donati, Maria Alice; Fecarotta, Simona; Casa, Roberto Della; Deodato, Federica; Taurisano, Roberta; Di Rocco, Maja

    2017-06-01

    The aim of this study was to evaluate the muscle MRI pattern of 9 patients (median age: 6.5 ± 2.74 years) affected by classic infantile-onset Pompe disease who were treated with enzyme replacement therapy. We performed and qualitatively scored T1-weighted (T1-w) sequences of the facial, shoulder girdle, paravertebral, and lower limb muscles and short-tau inversion recovery (STIR) sequences of the lower limbs using the Mercuri and Morrow scales, respectively. On T1-w images, mild (grade 1) or moderate (grade 2) involvement was found in the tongue in 6 of 6 patients and in the adductor magnus muscle in 6 of 9. STIR hyperintensity was detected in all areas examined and was categorized as limited to mild in 5 of 8 patients. On T1-w sequences, mild/moderate adipose substitution in the adductor magnus and tongue muscles was documented. STIR edema-like alterations of thigh and calf muscles are novel findings. Correlations with biopsy findings and clinical parameters are needed to fully understand these findings. Muscle Nerve 55: 841-848, 2017. © 2016 Wiley Periodicals, Inc.

  1. Selective lateral laser thyroarytenoid myotomy for adductor spasmodic dysphonia.

    PubMed

    Hussain, A; Shakeel, M

    2010-08-01

    Selective lateral laser thyroarytenoid myotomy is a conceptually sound, simple, minimally invasive, repeatable and predictable new surgical procedure for treating adductor spasmodic dysphonia. This paper aims to introduce and describe the surgical technique, and to present a clinical case series and its outcomes. A prospective, clinical case series treated with selective lateral laser thyroarytenoid myotomy, with follow up of 2.5 years. Pre- and post-operative data were collected prospectively for patients undergoing selective lateral laser thyroarytenoid myotomy. These data included patient demographics, previous interventions for adductor spasmodic dysphonia, technical aspects of surgery and clinical outcome. Outcome data included clinical assessment, voice handicap index, need for further intervention, and patient satisfaction assessed by subjective improvement (detailed subjectively by the patients themselves and objectively using the Glasgow benefit inventory). Four patients (two men and two women; mean age 65 years; age range 41-80 years) were included. The mean duration of adductor spasmodic dysphonia was 11 years. All patients had previously been treated with botulinum toxin A. All patients reported improvement in voice quality, fluency, sustainability and elimination of voice breaks over 2.5 years' follow up. Clinical assessment revealed no alteration in mucosal wave, and complete relief of hyperadduction was observed on phonation. No patients required supplementary botulinum toxin treatment during follow up. Selective lateral laser thyroarytenoid myotomy seems to represent a curative procedure for adductor spasmodic dysphonia, a chronic, debilitating condition. This procedure is conceptually simple, minimally invasive and repeatable. It also seems to offer a safe and lasting alternative to botulinum toxin therapy.

  2. Extending the use of the gracilis muscle flap in perineal reconstruction surgery.

    PubMed

    Goldie, Stephen J; Almasharqah, Riyadh; Fogg, Quentin A; Anderson, William

    2016-08-01

    Reconstruction of the perineum is required following oncological resections. Plastic surgical techniques can be used to restore the aesthetics and function of the perineum. The gracilis myocutaneous flap provides a substantial skin paddle, with minimal donor site morbidity. The flap is pedicled on a perforator from the medial circumflex femoral artery, giving it limited reach across the perineum. Tunnelling the flap under the adductor longus muscle may free up more of the arterial pedicle, increasing its reach. On three female cadavers, bilateral gracilis flaps were raised in the standard surgical manner, giving six flaps in total. With the flaps pedicled across the perineum, the distance from the tip of each flap was measured to the anterior superior iliac spine (ASIS). The flaps were then tunnelled under the adductor longus muscle. The distances to the ASIS were measured again. The average pedicle length was greater than 7 cm. Tunnelling the flap under the adductor longus muscle increased the reach by more than 4 cm on average. Cadaveric dissection has shown that tunnelling of the flap in a novel way increase its reach across the perineum. This additional flexibility improves its use clinically and is of benefit to plastic surgeons operating in perineal reconstruction. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Parrotfish grazing ability: interspecific differences in relation to jaw-lever mechanics and relative weight of adductor mandibulae on an Okinawan coral reef

    PubMed Central

    2016-01-01

    Parrotfishes (family Labridae: Scarini) are regarded to have important roles for maintaining the ecosystem balance in coral reefs due to their removal of organic matter and calcic substrates by grazing. The purpose of the present study was to clarify the interspecific differences in grazing ability of five parrotfish species (Chlorurus sordidus, C. bowersi, Scarus rivulatus, S. niger and S. forsteni) in relation to interspecific differences in jaw-lever mechanics and the relative weight of the adductor mandibulae (muscles operating jaw closing). The grazing ability was calculated by using stomach contents (CaCO3 weight/organic matter weight) defined as the grazing ability index (GAI). There were significant interspecific differences in GAI (C. sordidus = C. bowersi > S. rivulatus > S. niger = S. forsteni). Teeth of C. sordidus and C. bowersi were protrusive-shape whereas teeth of S. rivulatus, S. niger and S. forsteni were flat-shape. C. sordidus and C. bowersihave jaw-lever mechanics producing a greater biting force and have a larger weight of adductor mandibulae. S. rivulatus has jaw-lever mechanics producing a greater biting force but a smaller weight of adductor mandibulae that produce an intermediate biting force. In contrast, S. niger and S. forsteni have jaw-lever mechanics producing a lesser biting force and have a smaller weight of adductor mandibulae. Feeding rates and foray size of S. rivulatus, S. niger and S. forsteni were greater than C. sordidus and C. bowersi. The degree in bioerosion (GAI × feeding rate) was the largest for S. rivulatusand the smallest for S. forsteni. The degree in bioerosion for C. sordidus was larger than S. niger whereas relatively equal between C. bowersi and S. niger. These results suggest that interspecific difference in GAI was explained by interspecific differences in teeth shape, jaw-lever mechanics and relative weight of adductor mandibulae. The interspecific difference in the degree of bioerosion suggests the

  4. Parrotfish grazing ability: interspecific differences in relation to jaw-lever mechanics and relative weight of adductor mandibulae on an Okinawan coral reef.

    PubMed

    Nanami, Atsushi

    2016-01-01

    Parrotfishes (family Labridae: Scarini) are regarded to have important roles for maintaining the ecosystem balance in coral reefs due to their removal of organic matter and calcic substrates by grazing. The purpose of the present study was to clarify the interspecific differences in grazing ability of five parrotfish species (Chlorurus sordidus, C. bowersi, Scarus rivulatus, S. niger and S. forsteni) in relation to interspecific differences in jaw-lever mechanics and the relative weight of the adductor mandibulae (muscles operating jaw closing). The grazing ability was calculated by using stomach contents (CaCO3 weight/organic matter weight) defined as the grazing ability index (GAI). There were significant interspecific differences in GAI (C. sordidus = C. bowersi > S. rivulatus > S. niger = S. forsteni). Teeth of C. sordidus and C. bowersi were protrusive-shape whereas teeth of S. rivulatus, S. niger and S. forsteni were flat-shape. C. sordidus and C. bowersihave jaw-lever mechanics producing a greater biting force and have a larger weight of adductor mandibulae. S. rivulatus has jaw-lever mechanics producing a greater biting force but a smaller weight of adductor mandibulae that produce an intermediate biting force. In contrast, S. niger and S. forsteni have jaw-lever mechanics producing a lesser biting force and have a smaller weight of adductor mandibulae. Feeding rates and foray size of S. rivulatus, S. niger and S. forsteni were greater than C. sordidus and C. bowersi. The degree in bioerosion (GAI × feeding rate) was the largest for S. rivulatusand the smallest for S. forsteni. The degree in bioerosion for C. sordidus was larger than S. niger whereas relatively equal between C. bowersi and S. niger. These results suggest that interspecific difference in GAI was explained by interspecific differences in teeth shape, jaw-lever mechanics and relative weight of adductor mandibulae. The interspecific difference in the degree of bioerosion suggests the

  5. Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain

    PubMed Central

    Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

    2014-01-01

    Background: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. Purpose: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Results: Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P < .001). No other hip strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Conclusion: Large eccentric hip adduction strength deficits were found in soccer players with adductor

  6. Psychological aspects of adductor spasmodic dysphonia: a prospective population controlled questionnaire study.

    PubMed

    Kaptein, A A; Hughes, B M; Scharloo, M; Hondebrink, N; Langeveld, T P M

    2010-02-01

    To examine psychosocial concomitants, illness perceptions, and treatment perceptions in patients with adductor spasmodic dysphonia. Prospective controlled cohort study. A tertiary care facility. Forty-nine out-patients (38 women, 11 men; average age of 52 years) with adductor spasmodic dysphonia completed a battery of reliable and validated psychometric assessment instruments. Control patients' data were derived from scores in questionnaires by samples in the formal Manuals of the questionnaires used. Psychosocial functioning, illness perceptions, and treatment perceptions. Scores on psychosocial measures were elevated in male patients especially, indicating levels of psychological morbidity significantly above those seen in the general population. Assessments of illness perceptions and treatment perceptions indicated that patients perceive that they have a very low degree of control over the disorder, and experience a high emotional impact from it. Voice Handicap Index scores illustrated substantial degrees of perceived handicap. Adductor spasmodic dysphonia is associated with significant negative psychosocial concomitants, coupled with low perceived control over the condition. Future research should elucidate the implications of illness perceptions and treatment perceptions for the biopsychosocial care of persons with adductor spasmodic dysphonia in order to improve self-management and enhance quality of life.

  7. Progression and variation of fatty infiltration of the thigh muscles in Duchenne muscular dystrophy, a muscle magnetic resonance imaging study.

    PubMed

    Li, Wenzhu; Zheng, Yiming; Zhang, Wei; Wang, Zhaoxia; Xiao, Jiangxi; Yuan, Yun

    2015-05-01

    The purpose of this study was to assess the progression and variation of fatty infiltration of the thigh muscles of Duchenne muscular dystrophy patients. Muscle magnetic resonance imaging was used to measure the degree of fatty infiltration of the thigh muscles of 171 boys with Duchenne muscular dystrophy (mean age, 6.09 ± 2.30 years). Fatty infiltration was assigned using a modified Mercuri's scale 0-5 (normal-severe). The gluteus maximus and adductor magnus were affected in patients less than two years old, followed by the biceps femoris. Quadriceps and semimembranosus were first affected at the age of five to six years; the sartorius, gracilis and adductor longus remained apparently unaffected until seven years of age. Fatty infiltration of all the thigh muscles developed rapidly after seven years of age. The standard deviation of the fatty infiltration scores ranged from 2.41 to 4.87 before five years old, and from 6.84 to 11.66 between six and ten years old. This study provides evidence of highly variable degrees of fatty infiltration in children of different ages with Duchenne muscular dystrophy, and indicates that fatty infiltration progresses more quickly after seven years of age. These findings may be beneficial for the selection of therapeutic regimens and the analysis of future clinical trials. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. The precision and torque production of common hip adductor squeeze tests used in elite football.

    PubMed

    Light, N; Thorborg, K

    2016-11-01

    Decreased hip adductor strength is a known risk factor for groin injury in footballers, with clinicians testing adductor strength in various positions and using different protocols. Understanding how reliable and how much torque different adductor squeeze tests produce will facilitate choosing the most appropriate method for future testing. In this study, the reliability and torque production of three common adductor squeeze tests were investigated. Test-retest reliability and cross-sectional comparison. Twenty elite level footballers (16-33 years) without previous or current groin pain were recruited. Relative and absolute test-retest reliability, and torque production of three adductor squeeze tests (long-lever in abduction, short-lever in adduction and short-lever in abduction/external rotation) were investigated. Each participant performed a series of isometric strength tests measured by hand-held dynamometry in each position, on two test days separated by two weeks. No systematic variation was seen for any of the tests when using the mean of three measures (ICC=0.84-0.97, MDC%=6.6-19.5). The smallest variation was observed when taking the mean of three repetitions in the long-lever position (ICC=0.97, MDC%=6.6). The long-lever test also yielded the highest mean torque values, which were 69% and 11% higher than the short-lever in adduction test and short-lever in abduction/external rotation test respectively (p<0.001). All three tests described in this study are reliable methods of measuring adductor squeeze strength. However, the test performed in the long-lever position seems the most promising as it displays high test-retest precision and the highest adductor torque production. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  9. [Effects of surgery on muscles on clinical and radiographic findings in the hip joint region in cerebral palsy patients].

    PubMed

    Schejbalová, A; Havlas, V

    2008-10-01

    PURPOSE OF THE STUDY Isolated or combined surgical procedures on muscles around the hip joint are currently indicated by many authors. In cerebral palsy patients they are regarded as essential intervention. MATERIAL In the years 2005-2007, surgery in the hip joint region was essential for 150 children between 3 and 18 years of age. At the time of surgery, the patients' locomotion ranged from stage 1 to stage 7 of the Vojta system. METHODS The outcome was evaluated by clinical and radiographic examination at 2 and 6 months post-operatively and hip migration percentage and Wiberg's CE angle were measured. RESULTS The best clinical and radiographic outcomes were achieved in children younger than 6 years of age. On the other hand, isolated transfer of the distal rectus femoris muscle significantly affected pelvis anteflexion in adolescent patients. The most marked decrease in migration percentage was found after adductor tenotomy combined with surgery on the iliopsoas muscle (55.6 %) or when the two procedures were combined with distal rectus femoris transfer. DISCUSSION Combined surigical procedures, i.e., adductor tenotomy, surgery on the iliopsoas muscle or rectus femoris muscle and medial hamstrings, with fixation using an abduction modified Atlanta brace, are effective in patients with marked lateral hip migration who are younger that 6 years. Isolated adductor tenotomy and distal transfer of the rectus femoris muscle markedly improve standing position in walking patients. CONCLUSION An appropriate combination of surgical procedures on muscles in the hip region and on medial hamstrings can significantly improve the patient's locomotion and, if lateral migration is present, help to avoid surgery on bones.

  10. Speech Intelligibility in Severe Adductor Spasmodic Dysphonia

    ERIC Educational Resources Information Center

    Bender, Brenda K.; Cannito, Michael P.; Murry, Thomas; Woodson, Gayle E.

    2004-01-01

    This study compared speech intelligibility in nondisabled speakers and speakers with adductor spasmodic dysphonia (ADSD) before and after botulinum toxin (Botox) injection. Standard speech samples were obtained from 10 speakers diagnosed with severe ADSD prior to and 1 month following Botox injection, as well as from 10 age- and gender-matched…

  11. Adductor tenotomy: its role in the management of sports-related chronic groin pain.

    PubMed

    Atkinson, Henry Dushan E; Johal, Parminder; Falworth, Mark S; Ranawat, Vijai S; Dala-Ali, Benan; Martin, David K

    2010-08-01

    Chronic adductor-related groin pain in athletes is debilitating and is often challenging to treat. Little is published on the surgical treatment when conservative measures fail. This single center study reviews the outcomes of 48 patients (68 groins) who underwent percutaneous adductor tenotomy for sports-related chronic groin pain. Questionnaire assessments were made preoperatively and at a minimum follow-up of 25 months. Mean pre-injury Tegner activity scores of 8.8 reduced to 6.1 post-injury and these improved to 7.7 following surgery (p < 0.001). Sixty percent of patients regained or bettered their pre-injury Tegner activity scores after the adductor surgery; however, mean post-surgical Tegner scores still remained lower than pre-injury scores (p < 0.001). No patient had been able to engage in their chosen sport at their full ability pre-operatively, and 40% had been unable to participate in any sporting activity. The mean return to sports was at 18.5 weeks postoperatively, with 54% returning to their pre-injury activity levels, and only 8% still unable to perform athletic activities at latest follow-up. Seventy-three percent patients rated the outcome of their surgery as excellent or very satisfactory, and only three patients would not have wished to undergo the procedure again if symptoms recurred or developed on the opposite side. No patients reported their outcome as worse. A 78.1% mean improvement in function and an 86.5% mean improvement in pain were reported, and these two measures showed statistically significant correlation (p = 0.01). Groin disability scores improved from a mean of 11.8 to 3.9, post-operatively (p < 0.001). Bruising was seen in 37% of procedures, 3 patients developed a scrotal hematoma and 1 patient had a superficial wound infection. One patient developed recurrent symptoms following re-injury 26 months post-surgery, and fully recovered following a further adductor tenotomy. Adductor tenotomy provides good symptomatic and functional

  12. Differential Roles for the Thyroarytenoid and Lateral Cricoarytenoid Muscles in Phonation

    PubMed Central

    Chhetri, Dinesh K.; Neubauer, Juergen

    2015-01-01

    Objective Laryngeal adductor muscle dysfunction is common cause of voice disorders. Reconstitution of adductor muscle function is often the target of therapy, but the effects of these muscles on voice production remain to be fully understood. This study investigated the differential roles of thyroarytenoid (TA) and lateral cricoarytenoid (LCA) muscles on voice production. Study Design Basic science study using an in vivo canine model of phonation. Methods The TA and LCA muscle nerve branches were stimulated to obtain 7 graded levels of muscle activation, from threshold to maximal contraction. The effects of LCA activation alone, TA activation alone, and combined TA and LCA activation on phonation onset parameters were investigated. Phonatory posture, phonation onset type, fundamental frequency (F0), phonation onset pressure, and airflow were evaluated. Results LCA activation closed the posterior glottis but mid-membranous gap remained. TA activation closed the membranous glottis but posterior gap remained. Complete glottal closure was obtained only with combined TA and LCA activation. Phonation onset with LCAs alone was characterized by multiple modes (soft, aperiodic, periodic), while with TAs alone was abrupt and periodic but had significant baseline noise. Combined muscle activation led to elimination of baseline noise with stable abrupt periodic onset of phonation. Combined muscle activation was also necessary for F0 variation. LCA assisted the TA in increasing subglottal pressure while concurrently reducing phonation onset airflow. Conclusion TA is necessary for F0 variation, stable onset phonation, and increased subglottal pressure but needs LCA for optimal effectiveness and to reduce airflow requirements with increased activation. PMID:26198167

  13. Effects of wide step walking on swing phase hip muscle forces and spatio-temporal gait parameters.

    PubMed

    Bajelan, Soheil; Nagano, Hanatsu; Sparrow, Tony; Begg, Rezaul K

    2017-07-01

    Human walking can be viewed essentially as a continuum of anterior balance loss followed by a step that re-stabilizes balance. To secure balance an extended base of support can be assistive but healthy young adults tend to walk with relatively narrower steps compared to vulnerable populations (e.g. older adults and patients). It was, therefore, hypothesized that wide step walking may enhance dynamic balance at the cost of disturbed optimum coupling of muscle functions, leading to additional muscle work and associated reduction of gait economy. Young healthy adults may select relatively narrow steps for a more efficient gait. The current study focused on the effects of wide step walking on hip abductor and adductor muscles and spatio-temporal gait parameters. To this end, lower body kinematic data and ground reaction forces were obtained using an Optotrak motion capture system and AMTI force plates, respectively, while AnyBody software was employed for muscle force simulation. A single step of four healthy young male adults was captured during preferred walking and wide step walking. Based on preferred walking data, two parallel lines were drawn on the walkway to indicate 50% larger step width and participants targeted the lines with their heels as they walked. In addition to step width that defined walking conditions, other spatio-temporal gait parameters including step length, double support time and single support time were obtained. Average hip muscle forces during swing were modeled. Results showed that in wide step walking step length increased, Gluteus Minimus muscles were more active while Gracilis and Adductor Longus revealed considerably reduced forces. In conclusion, greater use of abductors and loss of adductor forces were found in wide step walking. Further validation is needed in future studies involving older adults and other pathological populations.

  14. Anatomy of the Adductor Magnus Origin

    PubMed Central

    Obey, Mitchel R.; Broski, Stephen M.; Spinner, Robert J.; Collins, Mark S.; Krych, Aaron J.

    2016-01-01

    Background: The adductor magnus (AM) has historically been a potential source of confusion in patients with suspected proximal hamstring avulsion injuries. Purpose: To investigate the anatomic characteristics of the AM, including its osseous origin, anatomic dimensions, and relationship to the proximal hamstring tendons. Study Design: Descriptive laboratory study. Methods: Dissection of the AM origin was performed in 11 (8 cadavers) fresh-frozen hip-to-foot cadaveric hemipelvis specimens. The gross anatomy and architecture of the proximal hamstring and AM tendons were studied. After dissecting the hamstring tendons away from their origin, the dimension, shape, and orientation of the tendon footprints on the ischial tuberosity were determined. Results: The AM was identified in all cadaveric specimens. The mean tendon thickness (anterior to posterior [AP]) was 5.7 ± 2.9 mm. The mean tendon width (medial to lateral [ML]) was 7.1 ± 2.2 mm. The mean tendon length was 13.1 ± 8.7 cm. The mean footprint height (AP dimension) was 12.1 ± 2.9 mm, and mean footprint width (ML dimension) was 17.3 ± 7.1 mm. The mean distance between the AM footprint and the most medial aspect of the conjoint tendon footprint was 8.5 ± 4.2 mm. Tendon measurements demonstrated a considerable degree of both intra- and interspecimen variability. Conclusion: The AM tendon is consistently present just medial to the conjoint tendon at the ischial tuberosity, representing the lateral-most portion of the AM muscle. This study found wide variation in the dimensional characteristics of the AM tendon between specimens. Its shape and location can mimic the appearance of an intact hamstring (conjoint or semimembranosus) tendon intraoperatively or on diagnostic imaging, potentially misleading surgeons and radiologists. Therefore, detailed knowledge of the AM tendon anatomy, footprint anatomy, and its relationship to the hamstring muscle complex is paramount when planning surgical approach and technique

  15. Arthroscopic pubic symphysis debridement and adductor enthesis repair in athletes with athletic pubalgia: technical note and video illustration.

    PubMed

    Hopp, Sascha; Tumin, Masjudin; Wilhelm, Peter; Pohlemann, Tim; Kelm, Jens

    2014-11-01

    We elaborately describe our novel arthroscopic technique of the symphysis pubis in athletes with osteitis pubis and concomitant adductor enthesopathy who fail to conservative treatment modalities. The symphysis pubis is debrided arthroscopically and the degenerated origin of adductor tendon (enthesis) is excised and reattached. With our surgical procedure the stability of the symphysis pubis is successfully preserved and the adductor longus enthesopathy simultaneously addressed in the same setting.

  16. Muscle contributions to knee extension in the early stance phase in patients with knee osteoarthritis.

    PubMed

    Ogaya, Shinya; Kubota, Ryo; Chujo, Yuta; Hirooka, Eiko; Kwang-Ho, Kim; Hase, Kimitaka

    2017-10-01

    The aim of this study was to analyze individual muscle contributions to knee angular acceleration using a musculoskeletal simulation analysis and evaluate knee extension mechanics in the early stance phase in patients with knee osteoarthritis (OA). The subjects comprised 15 patients with medial knee OA and 14 healthy elderly individuals. All participants underwent gait performance test using 8 infrared cameras and two force plates to measure the kinetic and kinematic data. The simulation was driven by 92 Hill-type muscle-tendon units of the lower extremities and a trunk with 23° of freedom. We analyzed each muscle contribution to knee angular acceleration in the 5%-15% and 15%-25% periods of the stance phase (% SP) using an induced acceleration analysis. We compared accelerations by individual muscles between the two groups using an analysis of covariance for controlling gait speed. Patients with knee OA had a significantly lesser knee extension acceleration by the vasti muscles and higher knee acceleration by hip adductors than those in controls in 5-15% SP. In addition, knee OA resulted in significantly lesser knee extension acceleration by the vasti muscles in 15-25% SP. These results indicate that patients with knee OA have decreased dependency on the vasti muscles to control knee movements during early stance phase. Hip adductor muscles, which mainly control mediolateral motion, partly compensate for the weak knee extension by the vasti muscles in patients with knee OA. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. 1H NMR-based metabolomics investigation on the effects of petrochemical contamination in posterior adductor muscles of caged mussel Mytilus galloprovincialis.

    PubMed

    Cappello, Tiziana; Maisano, Maria; Mauceri, Angela; Fasulo, Salvatore

    2017-08-01

    Environmental metabolomics is a high-throughout approach that provides a snapshot of the metabolic status of an organism. In order to elucidate the biological effects of petrochemical contamination on aquatic invertebrates, mussels Mytilus galloprovincialis were caged at the "Augusta-Melilli-Priolo" petrochemical area and Brucoli (Sicily, south Italy), chosen as the reference site. After confirming the elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and mercury (Hg) in Augusta sediments in our previous work (Maisano et al., 2016a), herein an environmental metabolomics approach based on protonic nuclear magnetic resonance ( 1 H NMR), coupled with chemometrics, was applied on the mussel posterior adductor muscle (PAM), the main muscular system in bivalve molluscs. Amino acids, osmolytes, energy storage compounds, tricarboxylic acid cycle intermediates, and nucleotides, were found in PAM NMR spectra. Principal Component Analysis (PCA) indicated that mussels caged at the polluted site clustered separately from mussels from the control area, suggesting a clear differentiation between their metabolic profiles. Specifically, disorders in energy metabolism, alterations in amino acids metabolism, and disturbance in the osmoregulatory processes were observed in mussel PAM. Overall, findings from this work demonstrated the usefulness of applying an active biomonitoring strategy for environmental risk assessment, and the effectiveness of metabolomics in elucidating changes in metabolic pathways of aquatic organisms caged at sites differentially contaminated, and thus its suitability to be applied in ecotoxicological studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. New insights into muscle function during pivot feeding in seahorses.

    PubMed

    Van Wassenbergh, Sam; Dries, Billy; Herrel, Anthony

    2014-01-01

    Seahorses, pipefish and their syngnathiform relatives are considered unique amongst fishes in using elastic recoil of post-cranial tendons to pivot the head extremely quickly towards small crustacean prey. It is known that pipefish activate the epaxial muscles for a considerable time before striking, at which rotations of the head and the hyoid are temporarily prevented to allow energy storage in the epaxial tendons. Here, we studied the motor control of this system in seahorses using electromyographic recordings of the epaxial muscles and the sternohyoideus-hypaxial muscles with simultaneous high-speed video recordings of prey capture. In addition we present the results from a stimulation experiment including the muscle hypothesised to be responsible for the locking and triggering of pivot feeding in seahorses (m. adductor arcus palatini). Our data confirmed that the epaxial pre-activation pattern observed previously for pipefish also occurs in seahorses. Similar to the epaxials, the sternohyoideus-hypaxial muscle complex shows prolonged anticipatory activity. Although a considerable variation in displacements of the mouth via head rotation could be observed, it could not be demonstrated that seahorses have control over strike distance. In addition, we could not identify the source of the kinematic variability in the activation patterns of the associated muscles. Finally, the stimulation experiment supported the previously hypothesized role of the m. adductor arcus palatini as the trigger in this elastic recoil system. Our results show that pre-stressing of both the head elevators and the hyoid retractors is taking place. As pre-activation of the main muscles involved in pivot feeding has now been demonstrated for both seahorses and pipefish, this is probably a generalized trait of Syngnathidae.

  19. New Insights into Muscle Function during Pivot Feeding in Seahorses

    PubMed Central

    Van Wassenbergh, Sam; Dries, Billy; Herrel, Anthony

    2014-01-01

    Seahorses, pipefish and their syngnathiform relatives are considered unique amongst fishes in using elastic recoil of post-cranial tendons to pivot the head extremely quickly towards small crustacean prey. It is known that pipefish activate the epaxial muscles for a considerable time before striking, at which rotations of the head and the hyoid are temporarily prevented to allow energy storage in the epaxial tendons. Here, we studied the motor control of this system in seahorses using electromyographic recordings of the epaxial muscles and the sternohyoideus-hypaxial muscles with simultaneous high-speed video recordings of prey capture. In addition we present the results from a stimulation experiment including the muscle hypothesised to be responsible for the locking and triggering of pivot feeding in seahorses (m. adductor arcus palatini). Our data confirmed that the epaxial pre-activation pattern observed previously for pipefish also occurs in seahorses. Similar to the epaxials, the sternohyoideus-hypaxial muscle complex shows prolonged anticipatory activity. Although a considerable variation in displacements of the mouth via head rotation could be observed, it could not be demonstrated that seahorses have control over strike distance. In addition, we could not identify the source of the kinematic variability in the activation patterns of the associated muscles. Finally, the stimulation experiment supported the previously hypothesized role of the m. adductor arcus palatini as the trigger in this elastic recoil system. Our results show that pre-stressing of both the head elevators and the hyoid retractors is taking place. As pre-activation of the main muscles involved in pivot feeding has now been demonstrated for both seahorses and pipefish, this is probably a generalized trait of Syngnathidae. PMID:25271759

  20. Feasibility and reliability of using an exoskeleton to emulate muscle contractures during walking.

    PubMed

    Attias, M; Bonnefoy-Mazure, A; De Coulon, G; Cheze, L; Armand, S

    2016-10-01

    Contracture is a permanent shortening of the muscle-tendon-ligament complex that limits joint mobility. Contracture is involved in many diseases (cerebral palsy, stroke, etc.) and can impair walking and other activities of daily living. The purpose of this study was to quantify the reliability of an exoskeleton designed to emulate lower limb muscle contractures unilaterally and bilaterally during walking. An exoskeleton was built according to the following design criteria: adjustable to different morphologies; respect of the principal lines of muscular actions; placement of reflective markers on anatomical landmarks; and the ability to replicate the contractures of eight muscles of the lower limb unilaterally and bilaterally (psoas, rectus femoris, hamstring, hip adductors, gastrocnemius, soleus, tibialis posterior, and peroneus). Sixteen combinations of contractures were emulated on the unilateral and bilateral muscles of nine healthy participants. Two sessions of gait analysis were performed at weekly intervals to assess the reliability of the emulated contractures. Discrete variables were extracted from the kinematics to analyse the reliability. The exoskeleton did not affect normal walking when contractures were not emulated. Kinematic reliability varied from poor to excellent depending on the targeted muscle. Reliability was good for the bilateral and unilateral gastrocnemius, soleus, and tibialis posterior as well as the bilateral hamstring and unilateral hip adductors. The exoskeleton can be used to replicate contracture on healthy participants. The exoskeleton will allow us to differentiate primary and compensatory effects of muscle contractures on gait kinematics. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. A pilot study to assess adductor canal catheter tip migration in a cadaver model.

    PubMed

    Leng, Jody C; Harrison, T Kyle; Miller, Brett; Howard, Steven K; Conroy, Myles; Udani, Ankeet; Shum, Cynthia; Mariano, Edward R

    2015-04-01

    An adductor canal catheter may facilitate early ambulation after total knee arthroplasty, but there is concern over preoperative placement since intraoperative migration of catheters may occur from surgical manipulation and result in ineffective analgesia. We hypothesized that catheter type and subcutaneous tunneling may influence tip migration for preoperatively inserted adductor canal catheters. In a male unembalmed human cadaver, 20 catheter insertion trials were divided randomly into one of four groups: flexible epidural catheter either tunneled or not tunneled; or rigid stimulating catheter either tunneled or not tunneled. Intraoperative patient manipulation was simulated by five range-of-motion exercises of the knee. Distance and length measurements were performed by a blinded regional anesthesiologist. Changes in catheter tip to nerve distance (p = 0.225) and length of catheter within the adductor canal (p = 0.467) were not different between the four groups. Two of five non-tunneled stimulating catheters (40 %) were dislodged compared to 0/5 in all other groups (p = 0.187). A cadaver model may be useful for assessing migration of regional anesthesia catheters; catheter type and subcutaneous tunneling may not affect migration of adductor canal catheters based on this preliminary study. However, future studies involving a larger sample size, actual patients, and other catheter types are warranted.

  2. Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain: An Assessor-Blinded Comparison.

    PubMed

    Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

    2014-02-01

    Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Cross-sectional study; Level of evidence, 3. Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P < .001). No other hip strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain compared with asymptomatic soccer players

  3. The Effect of Therapeutic Exercise on Long-Standing Adductor-Related Groin Pain in Athletes: Modified Hölmich Protocol

    PubMed Central

    Yousefzadeh, Abbas; Olyaei, Gholam Reza; Naseri, Nasrin; Khazaeipour, Zahra

    2018-01-01

    Objective The Hölmich protocol in therapeutic exercise is the most appropriate method for the treatment of long-standing adductor-related groin pain (LSAGP). Herein, we evaluated a modified Hölmich protocol to resolve the possible limitations intrinsic to the Hölmich protocol in terms of the rate of return to sport and the recovery period for athletes with LSAGP. Design The study followed a single-blind, before/after study design, where 15 athletes with LSAGP (mean age = 26.13 years; SD = 4.48) performed a 10-week modified Hölmich therapeutic exercise protocol. Results Outcome scores related to pain, hip adductor and abductor muscle strengths, and the ratio of maximum isometric and eccentric hip adduction to abduction strength increased significantly. Likewise, hip abduction and internal rotation ROM improved significantly compared to that at baseline. Furthermore, functional records (t-test, Edgren Side Step Test, and Triple Hop Test) showed significant improvement after treatment. Finally, 13 athletes (86.6% of the participants) successfully returned to sports activity in a mean time of 12.06 weeks (SD = 3.41). Conclusion The findings of this study objectively show that the modified Hölmich protocol may be safer and more effective than the Hölmich protocol in athletes with LSAGP in promoting their return to sports activity. This trial is registered with  IRCT2016080829269N1. PMID:29721339

  4. Effect of ractopamine-HCl supplementation for 28 days on carcass characteristics, muscle fiber morphometrics, and whole muscle yields of six distinct muscles of the loin and round.

    PubMed

    Gonzalez, J M; Johnson, S E; Stelzleni, A M; Thrift, T A; Savell, J D; Warnock, T M; Johnson, D D

    2010-07-01

    This study evaluated the effects of ractopamine-HCl (RAC) supplementation on carcass characteristics, muscle fiber morphometrics, and tenderness. Thirty-four steers (2 groups, 4 replicates) were fed RAC or carrier for 28 days prior to harvest. Seventy-two hours postmortem, the Longissimus lumborum (LL), Gracilis (GRA), Vastus lateralis (VL), Rectus femoris (RF), Semimembranosus (SM), and Adductor (ADD) were dissected from each carcass. Commodity weight, denuded weight, and muscle dimensions were collected. RAC supplementation tended to affect dressing percentage (P=0.15) and muscle firmness (P<0.15), and significantly affected lean maturity (P<0.05) and marbling score (P<0.05). With the exception of the LL and GRA (P<0.05), RAC had no effect on muscle dimensions. RAC did not influence the tenderness of vacuum-packaged, aged steaks as measured by Warner-Bratzler shear force. Muscle fiber size within the six muscles was unchanged (P>0.05) by RAC. Thus, RAC improves carcass parameters without a negative impact on tenderness. Copyright 2010 Elsevier Ltd. All rights reserved.

  5. Sonographic prevalence of groin hernias and adductor tendinopathy in patients with femoroacetabular impingement.

    PubMed

    Naal, Florian D; Dalla Riva, Francesco; Wuerz, Thomas H; Dubs, Beat; Leunig, Michael

    2015-09-01

    Femoroacetabular impingement (FAI) is a common debilitating condition that is associated with groin pain and limitation in young and active patients. Besides FAI, various disorders such as hernias, adductor tendinopathy, athletic pubalgia, lumbar spine affections, and others can cause similar symptoms. To determine the prevalence of inguinal and/or femoral herniation and adductor insertion tendinopathy using dynamic ultrasound in a cohort of patients with radiographic evidence of FAI. Case series; Level of evidence, 4. This retrospective study consisted of 74 patients (36 female and 38 male; mean age, 29 years; 83 symptomatic hips) with groin pain and radiographic evidence of FAI. In addition to the usual diagnostic algorithm, all patients underwent a dynamic ultrasound examination for signs of groin herniation and tendinopathy of the proximal insertion of the adductors. Evidence of groin herniation was found in 34 hips (41%). There were 27 inguinal (6 female, 21 male) and 10 femoral (9 female, 1 male) hernias. In 3 cases, inguinal and femoral herniation was coexistent. Overall, 5 patients underwent subsequent hernia repair. Patients with groin herniation were significantly older than those without (33 vs 27 years, respectively; P = .01). There were no significant differences for any of the radiographic or clinical parameters. Tendinopathy of the proximal adductor insertion was detected in 19 cases (23%; 11 female, 8 male). Tendinopathy was coexistent with groin herniation in 8 of the 19 cases. There were no significant differences for any of the radiographic or clinical parameters between patients with or without tendinopathy. Patients with a negative diagnostic hip injection result were more likely to have a concomitant groin hernia than those with a positive injection result (80% vs 27%, respectively). Overall, 38 hips underwent FAI surgery with satisfactory outcomes in terms of score values and subjective improvement. The results demonstrate that groin

  6. Effects of spaceflight in the adductor longus muscle of rats flown in the Soviet Biosatellite COSMOS 2044. A study employing neural cell adhesion molecule (N-CAM) immunocytochemistry and conventional morphological techniques (light and electron microscopy)

    NASA Technical Reports Server (NTRS)

    D'Amelio, F.; Daunton, N. G.

    1992-01-01

    The effects of spaceflight upon the "slow" muscle adductor longus were examined in rats flown in the Soviet Biosatellite COSMOS 2044. The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light microscopic observations revealed myofiber atrophy and segmental necrosis accompanied by cellular infiltrates composed of macrophages, leukocytes and mononuclear cells. Neural cell adhesion molecule immunoreactivity (N-CAM-IR) was seen on the myofiber surface and in regenerating myofibers. Ultrastructural alterations included Z band streaming, disorganization of myofibrillar architecture, sarcoplasmic degradation, extensive segmental necrosis with apparent preservation of the basement membrane, degenerative phenomena of the capillary endothelium and cellular invasion of necrotic areas. Regenerating myofibers were identified by the presence of increased amounts of ribosomal aggregates and chains of polyribosomes associated with myofilaments. The principal electron microscopic changes of the neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles replaced by microtubules and neurofilaments, degeneration of axon terminals, vacant axonal spaces and changes suggestive of axonal sprouting. The present observations suggest that alterations such as myofibrillar disruption and necrosis, muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight.

  7. Femoral Nerve Block versus Adductor Canal Block for Analgesia after Total Knee Arthroplasty.

    PubMed

    Koh, In Jun; Choi, Young Jun; Kim, Man Soo; Koh, Hyun Jung; Kang, Min Sung; In, Yong

    2017-06-01

    Inadequate pain management after total knee arthroplasty (TKA) impedes recovery, increases the risk of postoperative complications, and results in patient dissatisfaction. Although the preemptive use of multimodal measures is currently considered the principle of pain management after TKA, no gold standard pain management protocol has been established. Peripheral nerve blocks have been used as part of a contemporary multimodal approach to pain control after TKA. Femoral nerve block (FNB) has excellent postoperative analgesia and is now a commonly used analgesic modality for TKA pain control. However, FNB leads to quadriceps muscle weakness, which impairs early mobilization and increases the risk of postoperative falls. In this context, emerging evidence suggests that adductor canal block (ACB) facilitates postoperative rehabilitation compared with FNB because it primarily provides a sensory nerve block with sparing of quadriceps strength. However, whether ACB is more appropriate for contemporary pain management after TKA remains controversial. The objective of this study was to review and summarize recent studies regarding practical issues for ACB and comparisons of analgesic efficacy and functional recovery between ACB and FNB in patients who have undergone TKA.

  8. Hip adductor pyomyositis from Streptococcus mitis in a four-year-old child.

    PubMed

    Buldu, Metin Tolga; Raman, Raghu

    2016-01-01

    The unique aspect of this case study is the unusual history, presentation, ultrasonography, MRI and blood culture results, which lead to the diagnosis and treatment of adductor pyomyositis with a rare organism in a temperate country. The patient presented with a one-day history of malaise, fever, left groin pain and inability to weight bear on the left leg. There was no history of any trauma, predisposing infections or recent travel. Plain radiograph and ultrasound of the hip was normal with no effusion. Two consecutive blood cultures suggested Streptococcus mitis bacteraemia and MRI scan confirmed pyomyositis of the left hip adductors that was too small to drain. S. mitis is a normal commensal organism however it can lead to opportunistic infections particularly endocarditis. Echocardiogram revealed no cardiac complications, in particular no endocarditic vegetation. Patient was treated with intravenous benzylpenicillin for a week followed by oral phenoxymethylpenicillin for a week. Adductor pyomyositis must be considered as a differential diagnosis in a child with unusual presentation of hip pain. When an ultrasound is normal, MRI scan is warranted to confirm diagnosis. Septic screen should include blood cultures. The commonest causative organisms are the Staphylococcus family. However if S. mitis is isolated, cardiac sources of infection resulting in septic emboli must be investigated. Repeated MRI scans are required particularly if the patient does not respond to medical management. IV.

  9. Muscle sarcomere lesions and thrombosis after spaceflight and suspension unloading

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Riley, D.A.; Ellis, S.; Giometti, C.S.

    1992-08-01

    Extended exposure of humans to spaceflight produces a progressive loss of skeletal muscle strength. This process must be understood to design effective countermeasures. The present investigation examined hindlimb muscles from flight rats killed as close to landing as possible. Spaceflight and tail suspension-hindlimb unloading (unloaded) produced significant decreases in fiber cross-sectional areas of the adductor longus (AL), a slow-twitch antigravity muscle. However, the mean wet weight of the flight AL muscles was near normal, whereas that of the suspension unloaded AL muscles was significantly reduced. Interstitial edema within the flight AL, but not in the unloaded AL, appeared to accountmore » for this apparent disagreement.In both conditions, the slow-twitch oxidative fibers atrophied more than the fast-twitch oxidative-glycolytic fibers. Microcirculation was also compromised by spaceflight, such that there was increased formation of thrombi in the postcapillary venules and capillaries.« less

  10. The point-touch technique for botulinum toxin injection in adductor spasmodic dysphonia: quality of life assessment.

    PubMed

    Morzaria, S; Damrose, E J

    2011-07-01

    Botulinum toxin injection under electromyographic guidance is the 'gold standard' for adductor spasmodic dysphonia treatment. The point-touch technique, an alternative injection method which relies on anatomical landmarks, is cheaper, quicker and more accessible, but has not yet gained widespread acceptance due to concerns about patient satisfaction. To assess swallowing and voice-related quality of life following point-touch botulinum toxin injection in adductor spasmodic dysphonia patients. Stanford University Voice and Swallowing Center. Prospective case series (evidence level four). Consecutive adductor spasmodic dysphonia patients with a stable botulinum toxin dose-response relationship were recruited prospectively. The Eating Assessment Tool and Voice-Related Quality of Life questionnaires were completed pre-treatment and at 10 and 30 per cent completion of the injection cycle, respectively. Thirty-seven patients completed follow up. The mean total botulinum toxin dose was 0.88 units. Pre-treatment Voice-Related Quality of Life questionnaire results reflected the burden of disease. Post-treatment Eating Assessment Tool and Voice-Related Quality of Life questionnaire results were collected at 2.53 and 7.84 weeks, respectively; the former showed an increase in dysphagia, albeit statistically insignificant, while the latter showed significantly improved scores (both domain and total). The point-touch technique is a viable alternative for botulinum toxin injection in the treatment of adductor spasmodic dysphonia.

  11. Intrinsic Constraints on the Diversification of Neotropical Cichlid Adductor Mandibulae Size.

    PubMed

    Arbour, Jessica; López-Fernández, Hernán

    2018-02-01

    The diversification of functional traits may be constrained by intrinsic factors, such as structural, mechanical, developmental, or physiological limitations. We explored the biomechanical and constructional constraints on the size of the major jaw closing muscles, the adductor mandibulae complex (AM), in a diverse clade of freshwater fish - the Neotropical cichlids. Using phylogenetic comparative methods, we contrasted patterns of size variation and diversification rates of three AM divisions with variables describing head size and biomechanical coefficients describing force and velocity transmission. We found that all three AM muscles examined were impacted by constructional constraints, namely, (1) the space available in the head (head length and width-all AMs), (2) competition with the eye (AM1 and AM2), (3) competition for space among the three major AM divisions (e.g., AM1 vs. AM3), and (4) potentially the shape of the lower jaw (AM2). Only AM2 size was significantly associated with lower jaw biomechanical coefficients, but opposite predictions based on force transmission (i.e., no compensation for low mechanical advantage). Diversification rates of the mass of the divisions of the AM were also not connected to the diversification rates of their biomechanical coefficients. Previously suggested compensation in AM mass for reduced force transmission among ram-feeding predators appears to be driven by overall body plan changes (lengthening of the head in elongate bodies) and only indirectly to biomechanical trade-offs. Strong constructional constraints on AM size likely limit potentially functional morphospace occupation, and highlight the highly integrated nature of ram-suction feeding functional adaptations in Neotropical cichlids. Anat Rec, 301:216-226, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  12. Success of nonoperative management of adductor longus tendon ruptures in National Football League athletes.

    PubMed

    Schlegel, Theodore F; Bushnell, Brandon D; Godfrey, Jenna; Boublik, Martin

    2009-07-01

    Acute complete ruptures of the proximal adductor longus tendon are rare but challenging injuries to treat. The limited literature supports operative treatment, but data from management of chronic groin pain in athletes indicate that anatomical attachment of the tendon to the pubis may not be required for high-level function. Nonoperative management of complete adductor rupture can provide equal results to surgical repair in terms of return to play in the National Football League. Case series; Level of evidence, 4. Using the National Football League Injury Surveillance System, adductor tendon ruptures documented by magnetic resonance imaging were identified in 19 National Football League players from 1992 to 2004. The team physician for each respective player completed a survey with information about history, physical examination, magnetic resonance imaging findings, treatment, and outcomes. Statistics were analyzed with a Student unpaired t test. Fourteen players were treated nonoperatively, and 5 players were treated with surgical repair using suture anchors. In both groups, all players eventually returned to play in the National Football League. Mean time for return to play was 6.1 +/- 3.1 weeks (range, 3-12 weeks) for the nonoperative group and 12.0 +/- 2.5 weeks (range, 10-16 weeks) for the operative group (P = .001). One player in the operative group suffered the complication of a draining wound and heterotopic ossification. Players represented a variety of positions, and 12 of 19 (63%) had experienced prior symptoms or events. Nonoperative treatment of proximal adductor tendon rupture results in a statistically significantly faster return to play than does operative treatment in athletes competing in the National Football League and avoids the risks associated with surgery while providing an equal likelihood of return to play at the professional level.

  13. Chevron osteotomy with lateral release and adductor tenotomy for hallux valgus.

    PubMed

    Potenza, Vito; Caterini, Roberto; Farsetti, Pasquale; Forconi, Fabrizio; Savarese, Eugenio; Nicoletti, Simone; Ippolito, Ernesto

    2009-06-01

    Distal chevron osteotomy is a procedure widely performed for the surgical treatment of painful hallux valgus. The risks and benefits of a lateral capsular release and adductor tenotomy combined with chevron osteotomy are still debated. The aim of our study was to report the clinical and radiographic outcomes of this combined procedure in mild and moderate incongruent bunion deformities, with a hallux valgus angle (HVA) up to 40 degrees and an intermetatarsal angle (IMA) up to 20 degrees. Forty-two patients (52 feet) who consecutively underwent chevron osteotomy combined with lateral release and adductor tenotomy were reviewed 24-36 months after surgery. The mean age of the patients was 53.5 (range, 43 to 64) years. All the deformities were mild to moderate, with a mean preoperative value of 28 degrees in the HVA (range, 16 degrees to 40 degrees) and of 13 degrees in the IMA (range, 9 degrees to 20 degrees). At followup, the AOFAS hallux score improved from an average of 46 to an average of 88. The HVA and IMA had an average postoperative decrease respectively of 12 degrees and 6 degrees; lateral sesamoid displacement decreased by a mean of 15%. In no case did we observe infection or nonunion of the osteotomy. In one case, painless avascular necrosis of the first metatarsal head developed. Our short-term results show that distal chevron osteotomy combined with lateral release and adductor tenotomy is a feasible surgical option to address mild to moderate hallux valgus deformity, even with an IM angle between 15 and 20 degrees. Clinical and radiographic outcomes are generally good and patient satisfaction is generally high.

  14. Proteomics and immunohistochemistry identify the expression of α-cardiac myosin heavy chain in the jaw-closing muscles of sooty mangabeys (order Primates).

    PubMed

    Wall, Christine E; Holmes, Megan; Soderblom, Erik J; Taylor, Andrea B

    2018-07-01

    The jaw-closing muscles of humans and nonprimate mammals express alpha-cardiac fibers but MyHC α-cardiac has not been identified in the jaw adductors of nonhuman primates. We determined whether MyHC α-cardiac is expressed in the superficial masseter and temporalis muscles of the sooty mangabey (Cercocebus atys), an African Old World monkey that specializes on hard seeds. LC-MS/MS based proteomics was used to identify the presence of MyHC Iα. Immunohistochemistry was used to analyze the composition and distribution of fiber types in the superficial masseter and temporalis muscles of eight C. atys. Serial sections were stained against MyHC α-cardiac (MYH6), as well as MyHC-1 (NOQ7.5.4D), MyHC-2 (MY-32), and MyHC-M (2F4). Proteomics analysis identified the presence of Myosin-6 (MyHC α-cardiac) in both heart atrium and superficial masseter. MyHC α-cardiac was expressed in abundance in the superficial masseter and temporalis muscles of all eight individuals and hybrid fibers were common. The identification of MyHC α-cardiac in the jaw adductors of sooty mangabeys is a novel finding for nonhuman primates. The abundance of MyHC α-cardiac indicates a fatigue-resistant fiber population characterized by intermediate speed of contraction between pure MyHC-1 and MyHC-2 isoforms. We suggest that α-cardiac fibers may be advantageous to sooty mangabeys, whose feeding behavior includes frequent crushing of relatively large, hard seeds during the power stroke of ingestion. Additional studies comparing jaw-adductor fiber phenotype of hard-object feeding primates and other mammals are needed to explore this relationship further. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Bone scanning in the adductor insertion avulsion syndrome.

    PubMed

    Mahajan, Madhuri Shimpi

    2013-05-01

    A thigh splint (adductor insertion avulsion syndrome) is a relatively uncommon diagnosis analogous to shin splints. This article reports a 19-year-old female patient NOT a regular athlete who presented with groin pain. Physical examination was non-specific; magnetic resonance imaging pelvis did not reveal any abnormality. Patient referred for whole body bone scan, especially to locate any abnormality in the spine. This study highlights the role of whole body bone scan in the evaluation of groin pain and importance of evaluation of whole lower extremity.

  16. Femoral Nerve Block versus Adductor Canal Block for Analgesia after Total Knee Arthroplasty

    PubMed Central

    Koh, In Jun; Choi, Young Jun; Kim, Man Soo; Koh, Hyun Jung; Kang, Min Sung; In, Yong

    2017-01-01

    Inadequate pain management after total knee arthroplasty (TKA) impedes recovery, increases the risk of postoperative complications, and results in patient dissatisfaction. Although the preemptive use of multimodal measures is currently considered the principle of pain management after TKA, no gold standard pain management protocol has been established. Peripheral nerve blocks have been used as part of a contemporary multimodal approach to pain control after TKA. Femoral nerve block (FNB) has excellent postoperative analgesia and is now a commonly used analgesic modality for TKA pain control. However, FNB leads to quadriceps muscle weakness, which impairs early mobilization and increases the risk of postoperative falls. In this context, emerging evidence suggests that adductor canal block (ACB) facilitates postoperative rehabilitation compared with FNB because it primarily provides a sensory nerve block with sparing of quadriceps strength. However, whether ACB is more appropriate for contemporary pain management after TKA remains controversial. The objective of this study was to review and summarize recent studies regarding practical issues for ACB and comparisons of analgesic efficacy and functional recovery between ACB and FNB in patients who have undergone TKA. PMID:28545172

  17. Interactive effects of growth hormone and exercise on muscle mass in suspended rats

    NASA Technical Reports Server (NTRS)

    Grindeland, Richard E.; Roy, Roland R.; Edgerton, V. Reggie; Grossman, Elena J.; Mukku, Venkat R.; Jiang, Bian; Pierotti, David J.; Rudolph, Ingrid

    1994-01-01

    Measures to attenuate muscle atrophy in rats in response to simulated microgravity (hindlimb suspension (HS)) have been only partially successful. In the present study, hypophysectomized rats were in HS for 7 days, and the effects of recombinant human growth hormone (GH), exercise (Ex), or GH+Ex on the weights, protein concentrations, and fiber cross-sectional areas (CSAs) of hindlimb muscles were determined. The weights of four extensor muscles, i.e., the soleus (Sol), medial (MG) and lateral (LG) gastrocnemius, and plantaris (Plt), and one adductor, i.e., the adductor longus (AL), were decreased by 10-22% after HS. Fiber CSAs were decreased by 34% in the Sol and by 1 17% in the MG after HS. In contrast, two flexors, i.e., the tibialis anterior (TA) and extensor digitorum longus (EDL), did not atrophy. In HS rats, GH treatment alone maintained the weights of the fast extensors (MG, LG, Plt) and flexors (TA, EDL) at or above those of control rats. This effect was not observed in the slow extensor (Sol) or AL. Exercise had no significant effect on the weight of any muscle in HS rats. A combination of GH and Ex treatments yielded a significant increase in the weights of the fast extensors and in the CSA of both fast and slow fibers of the MG and significantly increased Sol weight and CSA of the slow fibers of the Sol. The AL was not responsive to either GH or Ex treatments. Protein concentrations of the Sol and MG were higher only in the Sol of Ex and GH+Ex rats. These results suggest that while GH treatment or intermittent high intensity exercise alone have a minimal effect in maintaining the mass of unloaded muscle, there is a strong interactive effect of these two treatments.

  18. Bone Scanning in the Adductor Insertion Avulsion Syndrome

    PubMed Central

    Mahajan, Madhuri Shimpi

    2013-01-01

    A thigh splint (adductor insertion avulsion syndrome) is a relatively uncommon diagnosis analogous to shin splints. This article reports a 19-year-old female patient NOT a regular athlete who presented with groin pain. Physical examination was non-specific; magnetic resonance imaging pelvis did not reveal any abnormality. Patient referred for whole body bone scan, especially to locate any abnormality in the spine. This study highlights the role of whole body bone scan in the evaluation of groin pain and importance of evaluation of whole lower extremity. PMID:25126001

  19. Lymphaticovenous Anastomoses for Lymphedema Complicated by Severe Lymphorrhea Following Resection of Soft-Tissue Sarcomas of the Adductor Compartment: A Report of Two Cases.

    PubMed

    Kobayashi, Hiroshi; Iida, Takuya; Yamamoto, Takumi; Ikegami, Masachika; Shinoda, Yusuke; Tanaka, Sakae; Kawano, Hirotaka

    2017-01-01

    Lymphedema and lymphorrhea are major causes of wound complications after the resection of soft-tissue sarcomas in the adductor compartment of the thigh. We report 2 cases of successful treatment of lymphedema and lymphorrhea, which had been refractory to nonoperative treatment, with use of lymphaticovenous anastomosis (LVA) and intraoperative indocyanine green lymphography after the resection of a sarcoma in the adductor compartment. These 2 cases highlight that LVA can be a useful and minimally invasive alternative to myocutaneous flaps for the treatment of wound complications caused by lymphedema and lymphorrhea after surgery for soft-tissue sarcomas in the adductor compartment of the thigh.

  20. Acoustic Variations in Adductor Spasmodic Dysphonia as a Function of Speech Task.

    ERIC Educational Resources Information Center

    Sapienza, Christine M.; Walton, Suzanne; Murry, Thomas

    1999-01-01

    Acoustic phonatory events were identified in 14 women diagnosed with adductor spasmodic dysphonia (ADSD), a focal laryngeal dystonia that disturbs phonatory function, and compared with those of 14 age-matched women with no vocal dysfunction. Findings indicated ADSD subjects produced more aberrant acoustic events than controls during tasks of…

  1. A mini-invasive adductor magnus tendon transfer technique for medial patellofemoral ligament reconstruction: a technical note.

    PubMed

    Sillanpää, Petri J; Mäenpää, Heikki M; Mattila, Ville M; Visuri, Tuomo; Pihlajamäki, Harri

    2009-05-01

    Patellar dislocations are associated with injuries to the medial patellofemoral ligament (MPFL). Several techniques for MPFL reconstruction have been recently published with some disadvantages involved, including large skin incisions and donor site morbidity. Arthroscopic stabilizing techniques carry the potential of inadequate restoration of MPFL function. We present a minimally invasive technique for MPFL reconstruction using adductor magnus tendon autograft. This technique is easily performed, safe, and provides a stabilizing effect equal to current MPFL reconstructions. Skin incision of only 3-4 cm is located at the level of the proximal half of the patella. After identifying the distal insertion of the adductor magnus tendon, a tendon harvester is introduced to harvest the medial two-thirds of the tendon, while the distal insertion is left intact. The adductor magnus tendon is cut at 12-14 cm from its distal insertion and transferred into the patellar medial margin. Two suture anchors are inserted through the same incision at the superomedial aspect of the patella in the anatomic MPFL origin. The graft is tightened at 30 degrees knee flexion. Aftercare includes 4 weeks of brace treatment with restricted range of motion.

  2. Skeletal muscle fiber, nerve, and blood vessel breakdown in space-flown rats

    NASA Technical Reports Server (NTRS)

    Riley, D. A.; Ilyina-Kakueva, E. I.; Ellis, S.; Bain, J. L.; Slocum, G. R.; Sedlak, F. R.

    1990-01-01

    Histochemical and ultrastructural analyses were performed postflight on hind limb skeletal muscles of rats orbited for 12.5 days aboard the unmanned Cosmos 1887 biosatellite and returned to Earth 2 days before sacrifice. The antigravity adductor longus (AL), soleus, and plantaris muscles atrophied more than the non-weight-bearing extensor digitorum longus, and slow muscle fibers were more atrophic than fast fibers. Muscle fiber segmental necrosis occurred selectively in the AL and soleus muscles; primarily, macrophages and neutrophils infiltrated and phagocytosed cellular debris. Granule-rich mast cells were diminished in flight AL muscles compared with controls, indicating the mast cell secretion contributed to interstitial tissue edema. Increased ubiquitination of disrupted myofibrils implicated ubiquitin in myofilament degradation. Mitochondrial content and succinic dehydrogenase activity were normal, except for subsarcolemmal decreases. Myofibrillar ATPase activity of flight AL muscle fibers shifted toward the fast type. Absence of capillaries and extravasation of red blood cells indicated failed microcirculation. Muscle fiber regeneration from activated satellite cells was detected. About 17% of the flight AL end plates exhibited total or partial denervation. Thus, skeletal muscle weakness associated with spaceflight can result from muscle fiber atrophy and segmental necrosis, partial motor denervation, and disruption of the microcirculation.

  3. The Effect of Adductor Canal Block on Knee Extensor Muscle Strength 6 Weeks After Total Knee Arthroplasty: A Randomized, Controlled Trial.

    PubMed

    Rousseau-Saine, Nicolas; Williams, Stephan R; Girard, François; Hébert, Luc J; Robin, Florian; Duchesne, Luc; Lavoie, Frédéric; Ruel, Monique

    2018-03-01

    Total knee arthroplasty (TKA) reduces knee extensor muscle strength (KES) in the operated limb for several months after the surgery. Immediately after TKA, compared to either inguinal femoral nerve block or placebo, adductor canal block (ACB) better preserves KES. Whether this short-term increase in KES is maintained several weeks after surgery remains unknown. We hypothesized that 48 hours of continuous ACB immediately after TKA would improve KES 6 weeks after TKA, compared to placebo. Patients scheduled for primary unilateral TKA were randomized to receive either a continuous ACB (group ACB) or a sham block (group SHAM) for 48 hours after surgery. Primary outcome was the difference in maximal KES 6 weeks postoperatively, measured with a dynamometer during maximum voluntary isometric contraction. Secondary outcomes included postoperative day 1 (POD1) and day 2 (POD2) KES, pain scores at rest and peak effort, and opioid consumption; variation at 6 weeks of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of hospital stay. Sixty-three subjects were randomized and 58 completed the study. Patients in group ACB had less pain at rest during POD1 and during peak effort on POD1 and POD2, consumed less opioids on POD1 and POD2, and had higher median KES on POD1. There was no significant difference between groups for median KES on POD2, variation of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of stay. There was no difference between groups in median KES 6 weeks after surgery (52 Nm [31-89 Nm] for group ACB vs 47 Nm [30-78 Nm] for group SHAM, P= .147). Continuous ACB provides better analgesia and KES for 24-48 hours after surgery, but does not affect KES 6 weeks after TKA. Further research could evaluate whether standardized and optimized rehabilitation over the long term would allow early KES improvements with ACB to be maintained over a period of weeks or months.

  4. Central activation, metabolites, and calcium handling during fatigue with repeated maximal isometric contractions in human muscle.

    PubMed

    Cairns, Simeon P; Inman, Luke A G; MacManus, Caroline P; van de Port, Ingrid G L; Ruell, Patricia A; Thom, Jeanette M; Thompson, Martin W

    2017-08-01

    To determine the roles of calcium (Ca 2+ ) handling by sarcoplasmic reticulum (SR) and central activation impairment (i.e., central fatigue) during fatigue with repeated maximal voluntary isometric contractions (MVC) in human muscles. Contractile performance was assessed during 3 min of repeated MVCs (7-s contraction, 3-s rest, n = 17). In ten participants, in vitro SR Ca 2+ -handling, metabolites, and fibre-type composition were quantified in biopsy samples from quadriceps muscle, along with plasma venous [K + ]. In 11 participants, central fatigue was compared using tetanic stimulation superimposed on MVC in quadriceps and adductor pollicis muscles. The decline of peak MVC force with fatigue was similar for both muscles. Fatigue resistance correlated directly with % type I fibre area in quadriceps (r = 0.77, P = 0.009). The maximal rate of ryanodine-induced Ca 2+ -release and Ca 2+ -uptake fell by 31 ± 26 and 28 ± 13%, respectively. The tetanic force depression was correlated with the combined reduction of ATP and PCr, and increase of lactate (r = 0.77, P = 0.009). Plasma venous [K + ] increased from 4.0 ± 0.3 to 5.4 ± 0.8 mM over 1-3-min exercise. Central fatigue occurred during the early contractions in the quadriceps in 7 out of 17 participants (central activation ratio fell from 0.98 ± 0.05 to 0.86 ± 0.11 at 1 min), but dwindled at exercise cessation. Central fatigue was seldom apparent in adductor pollicis. Fatigue with repeated MVC in human limb muscles mainly involves peripheral aspects which include impaired SR Ca 2+ -handling and we speculate that anaerobic metabolite changes are involved. A faster early force loss in quadriceps muscle with some participants is attributed to central fatigue.

  5. Overuse Injury Assessment Model

    DTIC Science & Technology

    2005-03-01

    superficialis Hip (Pelvis) Flexion Iliopsoas complex, rectus femoris, tensor fasciae latae, sartorius, pectineus Extension Semitendinosus, semimembranosus...Plantar flexion Gastrocnemius, soleus, tibialis posterior, peroneous muscles, Foot flexor muscles Spine Flexion Rectus abdominis, oblique muscles Extension...digitorum superficialis Hip Flexion Iliopsoas complex, rectus femoris, tensor fasciae latae, sartorius, pectineus, adductor magnus, adductor longus

  6. Muscle MRI in female carriers of dystrophinopathy.

    PubMed

    Tasca, G; Monforte, M; Iannaccone, E; Laschena, F; Ottaviani, P; Silvestri, G; Masciullo, M; Mirabella, M; Servidei, S; Ricci, E

    2012-09-01

    Duchenne muscular dystrophy carriers represent a rare condition that needs to be recognized because of the possible implications for prenatal diagnosis. Muscle biopsy is currently the diagnostic instrument of choice in sporadic patients. We wanted to verify whether muscle magnetic resonance imaging (MRI) could identify a pattern of involvement suggestive of this condition and whether it was similar to that reported in Duchenne and Becker muscular dystrophy. Evaluation of pelvic and lower limb MRI scans of 12 dystrophinopathy carriers was performed. We found a frequent involvement of the quadratus femoris, gluteus maximus and medius, biceps femoris long head, adductor magnus, vasti and paraspinal muscles, whilst the popliteus, iliopsoas, recti abdominis, sartorius, and gracilis were relatively spared. Asymmetry was a major feature on MRI; it could be detected significantly more often than with sole clinical examination and even in patients without weakness. The pattern we describe here is similar to that reported in Duchenne and Becker muscular dystrophy, although asymmetry represents a major distinctive feature. Muscle MRI was more sensitive than clinical examination for detecting single muscle involvement and asymmetry. Further studies are needed to verify the consistency of this pattern in larger cohorts and to assess whether muscle MRI can improve diagnostic accuracy in carriers with normal dystrophin staining on muscle biopsy. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

  7. Experiment K-7-18: Effects of Spaceflight in the Muscle Adductor Longus of Rats Flown in the Soviet Biosatellite Cosmos 2044. Part 1; A Study Employing Neural Cell Adhesion Molecules (N-CAM) Immunocytochemistry and Conventional Morphological Techniques (Light and Electron Microscopy)

    NASA Technical Reports Server (NTRS)

    Daunton, N. G.; DAmelio, F.; Wu, L.; Ilyina-Kakueva, E. I.; Krasnov, I. B.; Hyde, T. M.; Sigworth, S. K.

    1994-01-01

    The effects of spaceflight upon the 'slow' muscle adductor longus was examined in rats flown in the Soviet Biosatellite COSMOS 2044. Three groups - synchronous, vivarium and basal served as controls. The techniques employed included standard methods for light microscopy, N-CAM immunocytochemistry and electron microscopy. Light microscopic observations revealed myofiber atrophy, contraction bands and segmental necrosis accompanied by cellular infiltrates composed of macrophages, leucocytes and mononuclear cells. N-CAM immunoreactivity was seen (N-CAM-IR) on the myofiber surface, satellite cells and in regenerating myofibers reminiscent of myotubes. Ultrastructural alterations included Z band streaming, disorganization of myofibrillar architecture, sarcoplasmic degradation, extensive segmental necrosis with preservation of the basement membrane, degenerative phenomena of the capillary endothelium and cellular invasion of necrotic areas. Regenerating myofibers were identified by the presence of increased amounts of ribosomal aggregates and chains of polyribosomes associated with myofilaments that displayed varied distributive patterns. The principal electron microscopic changes of the neuromuscular junctions consisted of a decrease or absence of synaptic vesicles, degeneration of axon terminals, increased number of microtubules, vacant axonal spaces and axonal sprouting. The present observations indicate that major alterations such as myofibrillar disruption and necrosis, muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight.

  8. Experiment K-6-09. Morphological and biochemical investigation of microgravity-induced nerve and muscle breakdown. Part 1: Investigation of nerve and muscle breakdown during spaceflight; Part 2: Biochemical analysis of EDL and PLT muscles

    NASA Technical Reports Server (NTRS)

    Riley, D. A.; Ellis, S.; Bain, J.; Sedlak, F.; Slocum, G.; Oganov, V.

    1990-01-01

    The present findings on rat hindlimb muscles suggest that skeletal muscle weakness induced by prolonged spaceflight can result from a combination of muscle fiber atrophy, muscle fiber segmental necrosis, degeneration of motor nerve terminals and destruction of microcirculatory vessels. Damage was confined to the red adductor longus (AL) and soleus muscles. The midbelly region of the AL muscle had more segmental necrosis and edema than the ends. Macrophages and neutrophils were the major mononucleated cells infiltrating and phagocytosing the cellular debris. Toluidine blue-positive mast cells were significantly decreased in Flight AL muscles compared to controls; this indicated that degranulation of mast cells contributed to tissue edema. Increased ubiquitination of disrupted myofibrils may have promoted myofilament degradation. Overall, mitochondria content and SDH activity were normal, except for a decrease in the subsarcolemmal region. The myofibrillar ATPase activity shifted toward the fast type in the Flight AL muscles. Some of the pathological changes may have occurred or been exacerbated during the 2 day postflight period of readaptation to terrestrial gravity. While simple atrophy should be reversible by exercise, restoration of pathological changes depends upon complex processes of regeneration by stem cells. Initial signs of muscle and nerve fiber regeneration were detected. Even though regeneration proceeds on Earth, the space environment may inhibit repair and cause progressive irreversible deterioration during long term missions. Muscles obtained from Flight rats sacrificed immediately (within a few hours) after landing are needed to distinguish inflight changes from postflight readaptation.

  9. Muscle Fatigue Affects the Interpolated Twitch Technique When Assessed Using Electrically-Induced Contractions in Human and Rat Muscles.

    PubMed

    Neyroud, Daria; Cheng, Arthur J; Bourdillon, Nicolas; Kayser, Bengt; Place, Nicolas; Westerblad, Håkan

    2016-01-01

    The interpolated twitch technique (ITT) is the gold standard to assess voluntary activation and central fatigue. Yet, its validity has been questioned. Here we studied how peripheral fatigue can affect the ITT. Repeated contractions at submaximal frequencies were produced by supramaximal electrical stimulations of the human adductor pollicis muscle in vivo and of isolated rat soleus fiber bundles; an extra stimulation pulse was given during contractions to induce a superimposed twitch. Human muscles fatigued by repeated 30-Hz stimulation trains (3 s on-1 s off) showed an ~80% reduction in the superimposed twitch force accompanied by a severely reduced EMG response (M-wave amplitude), which implies action potential failure. Subsequent experiments combined a less intense stimulation protocol (1.5 s on-3 s off) with ischemia to cause muscle fatigue, but which preserved M-wave amplitude. However, the superimposed twitch force still decreased markedly more than the potentiated twitch force; with ITT this would reflect increased "voluntary activation." In contrast, the superimposed twitch force was relatively spared when a similar protocol was performed in rat soleus bundles. Force relaxation was slowed by >150% in fatigued human muscles, whereas it was unchanged in rat soleus bundles. Accordingly, results similar to those in the human muscle were obtained when relaxation was slowed by cooling the rat soleus muscles. In conclusion, our data demonstrate that muscle fatigue can confound the quantification of central fatigue using the ITT.

  10. Inferring the Diets of Extinct Giant Lemurs from Osteological Correlates of Muscle Dimensions.

    PubMed

    Perry, Jonathan M G

    2018-02-01

    The jaw adductor muscles of extinct mammals are often reconstructed to elucidate paleoecological relationships and to make broad comparisons among taxa. Muscle lever arms, bite load arms, muscle dimensions, and gape are often also reconstructed to better understand feeding. Several different approaches to these and related goals are discussed here. A protocol for reconstructing muscle dimensions and bite force using biomechanically informative skull measurements and osteological proxies of muscle dimensions is described and applied to a case study of subfossil Malagasy lemurs. The results of this case study show that most subfossil lemurs emphasized the masseter and medial pterygoid muscles over the temporalis. This supports the inference that these extinct lemurs depended heavily on tough food like leaves. Exceptions include signals of hard-object feeding in Archaeolemur that vary between A. majori and A. edwardsi. Reconstructions of soft-tissue and function are important for understanding past ecological relationships. Even those based on well-supported osteological proxies from extant analogues have limitations for making precise inferences. Anat Rec, 301:343-362, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  11. Proximal Versus Distal Continuous Adductor Canal Blocks: Does Varying Perineural Catheter Location Influence Analgesia? A Randomized, Subject-Masked, Controlled Clinical Trial.

    PubMed

    Sztain, Jacklynn F; Khatibi, Bahareh; Monahan, Amanda M; Said, Engy T; Abramson, Wendy B; Gabriel, Rodney A; Finneran, John J; Bellars, Richard H; Nguyen, Patrick L; Ball, Scott T; Gonzales, Francis B; Ahmed, Sonya S; Donohue, Michael C; Padwal, Jennifer A; Ilfeld, Brian M

    2018-07-01

    A continuous adductor canal block provides analgesia after surgical procedures of the knee. Recent neuroanatomic descriptions of the thigh and knee led us to speculate that local anesthetic deposited in the distal thigh close to the adductor hiatus would provide superior analgesia compared to a more proximal catheter location. We therefore tested the hypothesis that during a continuous adductor canal nerve block, postoperative analgesia would be improved by placing the perineural catheter tip 2-3 cm cephalad to where the femoral artery descends posteriorly to the adductor hiatus (distal location) compared to a more proximal location at the midpoint between the anterior superior iliac spine and the superior border of the patella (proximal location). Preoperatively, subjects undergoing total knee arthroplasty received an ultrasound-guided perineural catheter inserted either in the proximal or distal location within the adductor canal in a randomized, subject-masked fashion. Subjects received a single injection of lidocaine 2% via the catheter preoperatively, followed by an infusion of ropivacaine 0.2% (8 mL/h basal, 4 mL bolus, 30 minutes lockout) for the study duration. After joint closure, the surgeon infiltrated the entire joint using 30 mL of ropivacaine (0.5%), ketorolac (30 mg), epinephrine (5 μg/mL), and tranexamic acid (2 g). The primary end point was the median level of pain as measured on a numeric rating scale (NRS) during the time period of 8:00 AM to 12:00 PM the day after surgery. For the primary end point, the NRS of subjects with a catheter inserted at the proximal location (n = 24) was a median (10th, 25th-75th, 90th quartiles) of 0.5 (0.0, 0.0-3.2, 5.0) vs 3.0 (0.0, 2.0-5.4, 7.8) for subjects with a catheter inserted in the distal location (n = 26; P = .011). Median and maximum NRSs were lower in the proximal group at all other time points, but these differences did not reach statistical significance. There were no clinically relevant or

  12. Control of muscle relaxation during anesthesia: a novel approach for clinical routine.

    PubMed

    Stadler, Konrad S; Schumacher, Peter M; Hirter, Sibylle; Leibundgut, Daniel; Bouillon, Thomas W; Glattfelder, Adolf H; Zbinden, Alex M

    2006-03-01

    During general anesthesia drugs are administered to provide hypnosis, ensure analgesia, and skeletal muscle relaxation. In this paper, the main components of a newly developed controller for skeletal muscle relaxation are described. Muscle relaxation is controlled by administration of neuromuscular blocking agents. The degree of relaxation is assessed by supramaximal train-of-four stimulation of the ulnar nerve and measuring the electromyogram response of the adductor pollicis muscle. For closed-loop control purposes, a physiologically based pharmacokinetic and pharmacodynamic model of the neuromuscular blocking agent mivacurium is derived. The model is used to design an observer-based state feedback controller. Contrary to similar automatic systems described in the literature this controller makes use of two different measures obtained in the train-of-four measurement to maintain the desired level of relaxation. The controller is validated in a clinical study comparing the performance of the controller to the performance of the anesthesiologist. As presented, the controller was able to maintain a preselected degree of muscle relaxation with excellent precision while minimizing drug administration. The controller performed at least equally well as the anesthesiologist.

  13. Goniometric Assessment of Muscle Tone of Preterm Infants and Impact of Gestational Age on Its Maturation in Indian Setting.

    PubMed

    Farmania, Rajni; Sitaraman, S; Das, Rashmi Ranjan

    2017-08-01

    The normative data on muscle tone of preterm infants by goniometric assessment in Indian setting are scarce. The aim of this study it to provide a normative objective data of muscle tone of preterm infants by gestation using goniometer. This was a prospective, observational study including preterm infants admitted in a tertiary care hospital from North India. The objective dimension of muscle tone assessment of 204 healthy preterm infants was done; 61 infants completed follow-up till 40 weeks' postconceptional age (PCA) and were compared to term infants. SPSS (version 16.0) was used. The intergroup comparison was done through ANOVA, and the localization of differences between the groups was determined through multiple comparisons by post hoc test. Mean gestational age was 34.3 ± 1.7 weeks. Angles were as follows: adductor = 100.1 ± 8.7, popliteal = 118.9 ± 8.6, dorsiflexion = 39.0 ± 9.0, heel to ear = 121.90 ± 7.90, wrist flexion = 46.0 ± 10.2, and arm recoil = 122.2° ± 16.6°. The evolution of muscle tone as indicated by heel-to-ear angle shows progressive maturation from 32 weeks' gestation while adductor angle, popliteal angle, and arm recoil mature predominantly after 36 weeks' gestation. Comparison of preterm infants to term at 40 weeks' PCA demonstrated significantly less tone in all except posture and heel to ear. Goniometric assessment provides a objective normative data of muscle tone for preterm infants. Maturation of heel to ear and posture evolves from 32 weeks onwards and are the earliest neurologic marker to mature in preterm infants independent of the gestational age at birth.

  14. Pre-season adductor squeeze test and HAGOS function sport and recreation subscale scores predict groin injury in Gaelic football players.

    PubMed

    Delahunt, Eamonn; Fitzpatrick, Helen; Blake, Catherine

    2017-01-01

    To determine if pre-season adductor squeeze test and HAGOS function, sport and recreation subscale scores can identify Gaelic football players at risk of developing groin injury. Prospective study. Senior inter-county Gaelic football team. Fifty-five male elite Gaelic football players (age = 24.0 ± 2.8 years, body mass = 84.48 ± 7.67 kg, height = 1.85 ± 0.06 m, BMI = 24.70 ± 1.77 kg/m 2 ) from a single senior inter-county Gaelic football team. Occurrence of groin injury during the season. Ten time-loss groin injuries were registered representing 13% of all injuries. The odds ratio for sustaining a groin injury if pre-season adductor squeeze test score was below 225 mmHg, was 7.78. The odds ratio for sustaining a groin injury if pre-season HAGOS function, sport and recreation subscale score was < 87.5 was 8.94. Furthermore, for each additional point on the numerical rating scale pain rating during performance of the adductor squeeze test, the odds of groin injury increased by 2.16. This study provides preliminary evidence that pre-season adductor squeeze test and HAGOS function, sport and recreation subscale scores can be used to identify Gaelic football players at risk of developing groin injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Cholinesterase activity in the tissues of bivalves Noah's ark shell (Arca noae) and warty venus (Venus verrucosa): characterisation and in vitro sensitivity to organophosphorous pesticide trichlorfon.

    PubMed

    Perić, Lorena; Ribarić, Luka; Nerlović, Vedrana

    2013-08-01

    Cholinesterase (ChE, EC 3.1.1.7) activity was investigated in gills and adductor muscle of two bivalve species: Arca noae and Venus verrucosa. The properties of ChEs were investigated using acetylcholine iodide (ASCh), butyrylcholine iodide (BSCh) and propionylcholine iodide (PrSCh) as substrates and eserine, BW254c51 and iso-OMPA as specific inhibitors. The highest level of ChE activity in crude tissue extracts was detected with PrSCh followed by ASCh, while values obtained with BSCh were apparently low, except in A. noae adductor muscle. The enzyme activity in A. noae gills and V. verrucosa gills and adductor muscle was significantly inhibited by BW254c51, but not with iso-OMPA. ChE activity in adductor muscle of A. noae was significantly reduced by both diagnostic inhibitors. The effect of organophosphorous pesticide trichlorfon on ChE activity was investigated in vitro in both species as well as in the gills of mussels Mytilus galloprovincialis. The highest sensitivity of ChE to trichlorfon was observed in A. noae gills and adductor muscle (IC50 1.6×10(-7)M and 1.1×10(-7)M, respectively), followed by M. galloprovincialis gills (IC50 1.0×10(-6)M) and V. verrucosa gills and adductor muscle (IC50 1.7×10(-5)M and 0.9×10(-5)M, respectively). The results of this study suggest the potential of ChE activity measurement in the tissues of A. noae as effective biomarker of OP exposure in marine environment. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Fatigue-related firing of distal muscle nociceptors reduces voluntary activation of proximal muscles of the same limb.

    PubMed

    Kennedy, David S; McNeil, Chris J; Gandevia, Simon C; Taylor, Janet L

    2014-02-15

    With fatiguing exercise, firing of group III/IV muscle afferents reduces voluntary activation and force of the exercised muscles. These afferents can also act across agonist/antagonist pairs, reducing voluntary activation and force in nonfatigued muscles. We hypothesized that maintained firing of group III/IV muscle afferents after a fatiguing adductor pollicis (AP) contraction would decrease voluntary activation and force of AP and ipsilateral elbow flexors. In two experiments (n = 10) we examined voluntary activation of AP and elbow flexors by measuring changes in superimposed twitches evoked by ulnar nerve stimulation and transcranial magnetic stimulation of the motor cortex, respectively. Inflation of a sphygmomanometer cuff after a 2-min AP maximal voluntary contraction (MVC) blocked circulation of the hand for 2 min and maintained firing of group III/IV muscle afferents. After a 2-min AP MVC, maximal AP voluntary activation was lower with than without ischemia (56.2 ± 17.7% vs. 76.3 ± 14.6%; mean ± SD; P < 0.05) as was force (40.3 ± 12.8% vs. 57.1 ± 13.8% peak MVC; P < 0.05). Likewise, after a 2-min AP MVC, elbow flexion voluntary activation was lower with than without ischemia (88.3 ± 7.5% vs. 93.6 ± 3.9%; P < 0.05) as was torque (80.2 ± 4.6% vs. 86.6 ± 1.0% peak MVC; P < 0.05). Pain during ischemia was reported as Moderate to Very Strong. Postfatigue firing of group III/IV muscle afferents from the hand decreased voluntary drive and force of AP. Moreover, this effect decreased voluntary drive and torque of proximal unfatigued muscles, the elbow flexors. Fatigue-sensitive group III/IV muscle nociceptors act to limit voluntary drive not only to fatigued muscles but also to unfatigued muscles within the same limb.

  17. [Stimuli phrases of adductor spasmodic dysphonia phonatory break in mandarin Chinese].

    PubMed

    Ge, Pingjiang; Ren, Qingyi; Chen, Zhipeng; Cheng, Qiuhui; Sheng, Xiaoli; Wang, Ling; Chen, Shaohua; Zhang, Siyi

    2015-12-01

    To investigate the characteristics of adductor spasmodic dysphonia phonatory break in mandarin Chinese and select the stimuli phrases. Thirty-eight patients with adductor spasmodic dysphonia were involved in this study. Standard phrase " fù mŭ xīn" and a speech corpus in mandarin Chinese with 229 syllables covering all vowel and constant of mandarin Chinese were selected. Every patient read the phrases above twice in normal speed and comfortable voice. Two auditory perpetual speech pathologists marked phonatory break syllables respectively. The frequency of phonatory break syllables and their located phrases were calculated, rated and described. The phrases including the most phonatory break syllables were selected as stimuli phrases, the phonatory break frequency of which was also higher than that of standard phrase "fù mŭ xīn". Phonatory break happened in the reading of all patients. The average number of phonatory break syllables was 14 (3-33). Phonatroy break occurred when saying 177 (77.3%) syllables in the speech corpus. The syllables "guŏ, rén, zāng, diàn, chē, gè, guăn, a, bā, ne, de" broke in 23.1%-41.0% patients. These syllables belonged to the phrases "pĭng guŏ, huŏ chē, shì de, nĭ shì gè hăo rén, wŏ mén shì yŏu zŏng shì bă qĭn shì nong dé hĕn zāng, wŏ mén nà biān yŏu wăng qiú yùn dong chăng, cān gŭan, jiŭ bā hé yī gè miàn bāo dìan, tā shì duō me kāng kăi a,wŏ yīng gāi zài xìn lĭ xiĕ yī xiē shén mē ne?". Thirty-seven patients (97.3%) had phonatory break in above mentioned words. Ratios of these words phonatory break also were more than "fù mŭ xīn". Adductor spasmodic dysphonic patients exhibited different degrees of phonatory break in mandarine Chinese. The phrases" shì de, pĭng guŏ, huŏ chē, nĭ shì gè hăo rén, wŏ mén nà biān yŏu wăng qiú yùn dong chăng, cān gŭan, jiŭ bā hé yī gè miàn bāo dìan, tā shì duō me kāng kăi a" were recommended as stimuli

  18. Muscle MRI in neutral lipid storage disease with myopathy carrying mutation c.187+1G>A.

    PubMed

    Xu, Chunxiao; Zhao, Yawen; Liu, Jing; Zhang, Wei; Wang, Zhaoxia; Yuan, Yun

    2015-06-01

    We describe the clinical and muscle MRI changes in 2 siblings with neutral lipid storage disease with myopathy (NLSDM) carrying the mutation c.187+1G>A. Peripheral blood smears, genetic tests, and muscle biopsies were performed. Thigh MRI was performed to observe fatty replacement, muscle edema, and muscle bulk from axial sections. Both siblings had similar fatty infiltration and edema. T1-weighted images of the gluteus maximus, adductor magnus, semitendinosus, and semimembranosus revealed marked and diffuse fatty infiltration. There was asymmetric involvement in biceps femoris and quadriceps. There was extensive fatty infiltration in the quadriceps, except for the rectus femoris. Gracilis and sartorius were relatively spared. Thigh muscle volume was decreased, while the gracilis and sartorius appeared to show compensatory hypertrophy. Compared with previous reports in NLSDM, MRI changes in this myopathy tended to be more severe. Asymmetry and relatively selective fatty infiltration were characteristics. © 2014 Wiley Periodicals, Inc.

  19. Shortened cortical silent period in adductor spasmodic dysphonia: evidence for widespread cortical excitability.

    PubMed

    Samargia, Sharyl; Schmidt, Rebekah; Kimberley, Teresa Jacobson

    2014-02-07

    The purpose of this study was to compare cortical inhibition in the hand region of the primary motor cortex between subjects with focal hand dystonia (FHD), adductor spasmodic dysphonia (AdSD), and healthy controls. Data from 28 subjects were analyzed (FHD n=11, 53.25 ± 8.74 y; AdSD: n=8, 56.38 ± 7.5 y; and healthy controls: n=941.67 ± 10.85 y). All subjects received single pulse TMS to the left motor cortex to measure cortical silent period (CSP) in the right first dorsal interosseus (FDI) muscle. Duration of the CSP was measured and compared across groups. A one-way ANCOVA with age as a covariate revealed a significant group effect (p<0.001). Post hoc analysis revealed significantly longer CSP duration in the healthy group vs. AdSD group (p<0.001) and FHD group (p<0.001). These results suggest impaired intracortical inhibition is a neurophysiologic characteristic of FHD and AdSD. In addition, the shortened CSP in AdSD provides evidence to support a widespread decrease in cortical inhibition in areas of the motor cortex that represent an asymptomatic region of the body. These findings may inform future investigations of differential diagnosis as well as alternative treatments for focal dystonias. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Side Differences of Thigh Muscle Cross-Sectional Areas and Maximal Isometric Muscle Force in Bilateral Knees with the Same Radiographic Disease Stage, but Unilateral Frequent Pain – Data from the Osteoarthritis Initiative

    PubMed Central

    Sattler, Martina; Dannhauer, Torben; Hudelmaier, Martin; Wirth, Wolfgang; Sänger, Alexandra M.; Kwoh, C. Kent; Hunter, David J.; Eckstein, Felix

    2012-01-01

    Objective To determine whether anatomical thigh muscle cross-sectional areas (MCSAs) and strength differ between osteoarthritis (OA) knees with frequent pain compared with contralateral knees without pain, and to examine the correlation between MCSAs and strength in painful versus painless knees. Methods 48 subjects (31 women; 17 men; age 45–78 years) were drawn from 4796 Osteoarthritis Initiative (OAI) participants, in whom both knees displayed the same radiographic stage (KLG2 or 3), one with frequent pain (most days of the month within the past 12 months) and the contralateral one without pain. Axial MR images were used to determine MCSAs of extensors, flexors and adductors at 35% femoral length (distal to proximal) and in two adjacent 5 mm images. Maximal isometric extensor and flexor forces were used as provided from the OAI data base. Results Painful knees showed 5.2% lower extensor MCSAs (p=0.00003; paired t-test), and 7.8% lower maximal extensor muscle forces (p=0.003) than contra-lateral painless knees. There were no significant differences in flexor forces, or flexor and adductor MCSAs (p>0.39). Correlations between force and MCSAs were similar in painful and painless OA knees (0.44muscles) compared with contra-lateral knees without knee pain with the same radiographic stage. Frequent pain does not appear to affect the correlations between MCSAs and strength in OA knees. The findings suggest that quadriceps strengthening exercise may be useful in treating symptomatic knee OA. PMID:22395037

  1. Centronuclear myopathy related to dynamin 2 mutations: Clinical, morphological, muscle imaging and genetic features of an Italian cohort

    PubMed Central

    Catteruccia, Michela; Fattori, Fabiana; Codemo, Valentina; Ruggiero, Lucia; Maggi, Lorenzo; Tasca, Giorgio; Fiorillo, Chiara; Pane, Marika; Berardinelli, Angela; Verardo, Margherita; Bragato, Cinzia; Mora, Marina; Morandi, Lucia; Bruno, Claudio; Santoro, Lucio; Pegoraro, Elena; Mercuri, Eugenio; Bertini, Enrico; D’Amico, Adele

    2013-01-01

    Mutations in dynamin 2 (DNM2) gene cause autosomal dominant centronuclear myopathy and occur in around 50% of patients with centronuclear myopathy. We report clinical, morphological, muscle imaging and genetic data of 10 unrelated Italian patients with centronuclear myopathy related to DNM2 mutations. Our results confirm the clinical heterogeneity of this disease, underlining some peculiar clinical features, such as severe pulmonary impairment and jaw contracture that should be considered in the clinical follow-up of these patients. Muscle MRI showed a distinct pattern of involvement, with predominant involvement of soleus and tibialis anterior in the lower leg muscles, followed by hamstring muscles and adductor magnus at thigh level and gluteus maximus. The detection of three novel DNM2 mutations and the first case of somatic mosaicism further expand the genetic spectrum of the disease. PMID:23394783

  2. Mini-titins in striated and smooth molluscan muscles: structure, location and immunological crossreactivity.

    PubMed

    Vibert, P; Edelstein, S M; Castellani, L; Elliott, B W

    1993-12-01

    Invertebrate mini-titins are members of a class of myosin-binding proteins belonging to the immunoglobulin superfamily that may have structural and/or regulatory properties. We have isolated mini-titins from three molluscan sources: the striated and smooth adductor muscles of the scallop, and the smooth catch muscles of the mussel. Electron microscopy reveals flexible rod-like molecules about 0.2 micron long and 30 A wide with a distinctive polarity. Antibodies to scallop mini-titin label the A-band and especially the A/I junction of scallop striated muscle myofibrils by indirect immunofluorescence and immuno-electron microscopy. This antibody crossreacts with mini-titins in scallop smooth and Mytilus catch muscles, as well as with proteins in striated muscles from Limulus, Lethocerus (asynchronous flight muscle), and crayfish. It labels the A/I junction (I-region in Lethocerus) in these striated muscles as well as in chicken skeletal muscle. Antibodies to the repetitive immunoglobulin-like regions and also to the kinase domain of nematode twitchin crossreact with scallop mini-titin and label the A-band of scallop myofibrils. Electron microscopy of single molecules shows that antibodies to twitchin kinase bind to scallop mini-titin near one end of the molecule, suggesting how the scallop structure might be aligned with the sequence of nematode twitchin.

  3. Biochemical and physical factors affecting discoloration characteristics of 19 bovine muscles.

    PubMed

    McKenna, D R; Mies, P D; Baird, B E; Pfeiffer, K D; Ellebracht, J W; Savell, J W

    2005-08-01

    Steaks from muscles (n=19 from nine beef carcasses) were evaluated over the course of retail display (0-, 1-, 2-, 3-, 4- or 5-d) for objective measures of discoloration (metmyoglobin, oxymyoglobin, L*-, a*-, and b*-values), reducing ability (metmyoglobin reductase activity (MRA), resistance to induced metmyoglobin formation (RIMF), and nitric oxide metmyoglobin reducing ability (NORA)), oxygen consumption rate (OCR), oxygen penetration depth, myoglobin content, oxidative rancidity, and pH. Muscles were grouped according to objective color measures of discoloration. M. longissimus lumborum, M. longissimus thoracis, M. semitendinosus, and M. tensor fasciae latae were grouped as "high" color stability muscles, M. semimembranosus, M. rectus femoris, and M. vastus lateralis were grouped as "moderate" color stability muscles, M. trapezius, M. gluteus medius, and M. latissimus dorsi were grouped as "intermediate" color stability muscles, M. triceps brachi - long head, M. biceps femoris, M. pectoralis profundus, M. adductor, M. triceps brachi - lateral head, and M. serratus ventralis were grouped as "low" color stability muscles, and M. supraspinatus, M. infraspinatus, and M. psoas major were grouped as "very low" color stability muscles. Generally, muscles of high color stability had high RIMF, nitric oxide reducing ability, and oxygen penetration depth and possessed low OCRs, myoglobin content, and oxidative rancidity. In contrast, muscles of low color stability had high MRA, OCRs, myoglobin content, and oxidative rancidity and low RIMF, NORA, and oxygen penetration depth. Data indicate that discoloration differences between muscles are related to the amount of reducing activity relative to the OCR.

  4. Muscle ultrasound elastography and MRI in preschool children with Duchenne muscular dystrophy.

    PubMed

    Pichiecchio, Anna; Alessandrino, Francesco; Bortolotto, Chandra; Cerica, Alessandra; Rosti, Cristina; Raciti, Maria Vittoria; Rossi, Marta; Berardinelli, Angela; Baranello, Giovanni; Bastianello, Stefano; Calliada, Fabrizio

    2018-06-01

    The aim of this study was to determine muscle tissue elasticity, measured with shear-wave elastography, in selected lower limb muscles of patients affected by Duchenne muscular dystrophy (DMD) and to correlate the values obtained with those recorded in healthy children and with muscle magnetic resonance imaging (MRI) data from the same DMD children, specifically the pattern on T1-weighted (w) and short-tau inversion recovery (STIR) sequences. Five preschool DMD children and five age-matched healthy children were studied with shear-wave elastography. In the DMD children, muscle stiffness was moderately higher compared with the muscle stiffness in HC, in the rectus femoris, vastus lateralis, adductor magnus and gluteus maximus muscles. On muscle MRI T1-w images showed fatty replacement in 3/5 patients at the level of the GM, while thigh and leg muscles were affected in 2/5; hyperintensity on STIR images was identified in 4/5 patients. No significant correlation was observed between stiffness values and MRI scoring. Our study demonstrated that lower limb muscles of preschool DMD patients show fatty replacement and patchy edema on muscle MRI and increased stiffness on shear-wave elastography. In conclusion, although further studies in larger cohorts are needed, shear-wave elastography could be considered a useful non-invasive tool to easily monitor muscle changes in early stages of the disease. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Upper Extremity Muscle Volumes and Functional Strength After Resistance Training in Older Adults

    PubMed Central

    Daly, Melissa; Vidt, Meghan E.; Eggebeen, Joel D.; Simpson, W. Greg; Miller, Michael E.; Marsh, Anthony P.; Saul, Katherine R.

    2014-01-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p < .01 for all exercises). Compared with controls, randomization to RT led to greater functional pulling strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions. PMID:22952203

  6. Jaw muscle fiber type distribution in Hawaiian gobioid stream fishes: histochemical correlations with feeding ecology and behavior.

    PubMed

    Maie, Takashi; Meister, Andrew B; Leonard, Gerald L; Schrank, Gordon D; Blob, Richard W; Schoenfuss, Heiko L

    2011-12-01

    Differences in fiber type distribution in the axial muscles of Hawaiian gobioid stream fishes have previously been linked to differences in locomotor performance, behavior, and diet across species. Using ATPase assays, we examined fiber types of the jaw opening sternohyoideus muscle across five species, as well as fiber types of three jaw closing muscles (adductor mandibulae A1, A2, and A3). The jaw muscles of some species of Hawaiian stream gobies contained substantial red fiber components. Some jaw muscles always had greater proportions of white muscle fibers than other jaw muscles, independent of species. In addition, comparing across species, the dietary generalists (Awaous guamensis and Stenogobius hawaiiensis) had a lower proportion of white muscle fibers in all jaw muscles than the dietary specialists (Lentipes concolor, Sicyopterus stimpsoni, and Eleotris sandwicensis). Among Hawaiian stream gobies, generalist diets may favor a wider range of muscle performance, provided by a mix of white and red muscle fibers, than is typical of dietary specialists, which may have a higher proportion of fast-twitch white fibers in jaw muscles to help meet the demands of rapid predatory strikes or feeding in fast-flowing habitats. Copyright © 2011 Elsevier GmbH. All rights reserved.

  7. Rectus abdominis muscle injuries in elite handball players: management and rehabilitation

    PubMed Central

    Balius, Ramon; Pedret, Carles; Pacheco, Laura; Gutierrez, Josep Antoni; Vives, Joan; Escoda, Jaume

    2011-01-01

    Muscle injuries generally occur in two-joint muscles with a high percentage of type II fibers during the performance of eccentric activity. Some muscle injuries, such as those located in the adductor longus, a monoarticular muscle, as well as rectus abdominis do not fully comply with these requirements. This study examines five cases of elite handball players with ruptured rectus abdominals. Sonographically, lesions in rectus abdominis are shown as a disruption of the fibrillar pattern with a hematic suffusion that invades the entire lesion. In some of the cases, the ultrasound study was complemented with a MRI. A unified rehabilitation protocol was applied and the return to play time of each handball player ranged between 16 and 22 days, with an average of 18.2 days. Follow-up at 15 months showed no evidence of re-injury or residual discomfort and all of them are playing at their highest level. The aim of this study was to illustrate a feature of handball injury that, as in tennis and volleyball, is uncommon and so far has not been specifically reported. The phenomenon of contralateral abdominal hypertrophy in handball appears in the dominant arm as in tennis and volleyball. PMID:24198573

  8. Single-Dose Adductor Canal Block With Local Infiltrative Analgesia Compared With Local Infiltrate Analgesia After Total Knee Arthroplasty: A Randomized, Double-Blind, Placebo-Controlled Trial.

    PubMed

    Nader, Antoun; Kendall, Mark C; Manning, David W; Beal, Matthew; Rahangdale, Rohit; Dekker, Robert; De Oliveira, Gildasio S; Kamenetsky, Eric; McCarthy, Robert J

    A single-dose adductor canal block can provide postoperative analgesia for patients undergoing total knee arthroplasty (TKA). The purpose of this study was to assess postoperative opioid consumption after ultrasound-guided single-injection bupivacaine compared with saline adductor canal block for patients undergoing TKA. After institutional review board approval, written informed consent was obtained from patients (>18 years old) undergoing elective TKA. Subjects were randomized into 2 groups as follows: adductor canal blockade with 10 mL of bupivacaine 0.25% with epinephrine 1:300,000 or 10 mL of normal saline. All patients received a periarticular infiltration mixture intraoperatively with scheduled and patient requested oral and IV analgesics postoperatively for breakthrough pain. Personnel blinded to group allocation recorded pain scores and opioid consumption every 6 hours. Pain burden, area under the numeric rating score for pain, was calculated for 36 hours. The primary outcome was postoperative IV/IM morphine (mg morEq) consumption at 36 hours after surgery. Forty (28 women/12 men) subjects were studied. Postoperative opioid consumption was reduced in the bupivacaine 48 (39 to 61) mg morEq compared with saline 60 (49 to 85) mg morEq, difference -12 (-33 to -2) mg morEq (P = 0.03). Pain burden at rest was decreased in the bupivacaine 71 (37 to 120) score · hours compared with saline 131 (92 to 161) score · hours, difference -60 (-93 to -14) score · hours (P = 0.009). Adductor canal blockade with bupivacaine 0.25% with epinephrine 1:300,000 effectively reduces pain and opioid requirement in the postoperative period after TKA. Adductor canal blockade is an effective pain management adjunct for patients undergoing TKA.

  9. Muscle Contributions to Frontal Plane Angular Momentum during Walking

    PubMed Central

    Neptune, Richard R.; McGowan, Craig P.

    2016-01-01

    The regulation of whole-body angular momentum is important for maintaining dynamic balance during human walking, which is particularly challenging in the frontal plane. Whole-body angular momentum is actively regulated by individual muscle forces. Thus, understanding which muscles contribute to frontal plane angular momentum will further our understanding of mediolateral balance control and has the potential to help diagnose and treat balance disorders. The purpose of this study was to identify how individual muscles and gravity contribute to whole-body angular momentum in the frontal plane using a muscle-actuated forward dynamics simulation analysis. A three-dimensional simulation was developed that emulated the average walking mechanics of a group of young healthy adults (n=10). The results showed that a finite set of muscles are the primary contributors to frontal plane balance and that these contributions vary throughout the gait cycle. In early stance, the vasti, adductor magnus and gravity acted to rotate the body towards the contralateral leg while the gluteus medius acted to rotate the body towards the ipsilateral leg. In late stance, the gluteus medius continued to rotate the body towards the ipsilateral leg while the soleus and gastrocnemius acted to rotate the body towards the contralateral leg. These results highlight those muscles that are critical to maintaining dynamic balance in the frontal plane during walking and may provide targets for locomotor therapies aimed at treating balance disorders. PMID:27522538

  10. MRI findings in soccer players with long-standing adductor-related groin pain and asymptomatic controls.

    PubMed

    Branci, Sonia; Thorborg, Kristian; Bech, Birthe Højlund; Boesen, Mikael; Nielsen, Michael Bachmann; Hölmich, Per

    2015-05-01

    Soccer players are commonly affected by long-standing adductor-related groin pain (ARGP), but the clinical significance of MRI findings in these athletes is largely unknown. Our aims were (1) to evaluate whether MRI findings are associated with long-standing ARGP in soccer players, (2) to assess MRI findings in asymptomatic soccer players and non-soccer playing controls. This cross-sectional study included 28 male soccer players with long-standing ARGP, 17 male asymptomatic soccer players and 20 male asymptomatic non-soccer playing athletes of matching age and athletic exposure. Participants underwent identical standardised and reliable clinical examination, and MRI scans (3 T) of the pelvis performed by a blinded observer. Images were consensus rated by three blinded radiologists according to a standardised MRI evaluation protocol. The associations between clinical adductor-related findings and pathological MRI findings were investigated with χ(2) statistics and OR. Central disc protrusion (p=0.027) and higher grades of pubic bone marrow oedema (BMO; p=0.027) were significantly more present in symptomatic players than asymptomatic players. However, up to 71% of asymptomatic soccer players displayed different positive MRI findings, and asymptomatic soccer players had significantly higher odds (OR ranging from 6.3 to 13.3) for BMO, adductor tendinopathy and degenerative changes than non-soccer players. ARGP in soccer players was associated with central disc protrusion and higher grades of pubic BMO. Moreover, positive MRI findings were significantly more frequent in soccer players compared with non-soccer players irrespective of symptoms, suggesting that these MRI changes may be associated with soccer play itself rather than clinical symptoms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Muscle MRI in Duchenne muscular dystrophy: Evidence of a distinctive pattern.

    PubMed

    Polavarapu, Kiran; Manjunath, Mahadevappa; Preethish-Kumar, Veeramani; Sekar, Deepha; Vengalil, Seena; Thomas, PriyaTreesa; Sathyaprabha, Talakad N; Bharath, Rose Dawn; Nalini, Atchayaram

    2016-11-01

    The purpose of this study was to describe the pattern of muscle involvement using MRI findings and correlate with functional as well as muscle strength measurements. Fifty genetically confirmed DMD children with a mean age of 7.6 ± 2.8 (4-15 years) underwent muscle MRI and qualitative assessment was done for muscle changes using Mercuri staging for fibro-fatty replacement on T1 sequence and Borsato score for myoedema on STIR sequence. Detailed phenotypic characterisation was done with Manual muscle testing (modified MRC grading) and Muscular Dystrophy Functional Rating Scale (MDFRS). Mercuri scoring showed severe fibro-fatty changes in Gluteus medius, minimus and Adductor magnus followed by moderate to severe changes in Gluteus maximus and Quadriceps muscles. Total sparing of Gracilis, Sartorius and Semimembranosus muscles was observed. Superficial posterior and lateral leg muscles were preferentially involved with sparing of deep posterior and anterior leg muscles. Myoedema showed significant inverse correlation with fatty infiltration in thigh muscles. Similarly, significant inverse correlation was observed between Mercuri scores and MRC grading as well as MDFRS scores. A direct linear correlation was observed between duration of illness and fibro-fatty changes in piriformis, quadriceps and superficial posterior leg muscles. There was no correlation between MRI findings and genotypic characteristics. However, this specific pattern of muscle involvement in MRI could aid in proceeding for genetic testing when clinical suspicion is high, thus reducing the need for muscle biopsy. Fibro fatty infiltration as measured by Mercuri scoring can be a useful marker for assessing the disease severity and progression. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Proteomic Changes in Rat Thyroarytenoid Muscle Induced by Botulinum Neurotoxin Injection

    PubMed Central

    Welham, Nathan V.; Marriott, Gerard; Tateya, Ichiro; Bless, Diane M.

    2009-01-01

    Botulinum neurotoxin (BoNT) injection into the thyroarytenoid (TA) muscle is a commonly performed medical intervention for adductor spasmodic dysphonia. The mechanism of action of BoNT at the neuromuscular junction is well understood, however, aside from reports focused on myosin heavy chain isoform abundance, there is a paucity of data addressing the effects of therapeutic BoNT injection on the TA muscle proteome. In this study, 12 adult Sprague Dawley rats underwent unilateral TA muscle BoNT serotype A injection followed by tissue harvest at 72 hrs, 7 days, 14 days, and 56 days post-injection. Three additional rats were reserved as controls. Proteomic analysis was performed using 2D SDS-PAGE followed by MALDI-MS. Vocal fold movement was significantly reduced by 72 hrs, with complete return of function by 56 days. Twenty-five protein spots demonstrated significant protein abundance changes following BoNT injection, and were associated with alterations in energy metabolism, muscle contractile function, cellular stress response, transcription, translation, and cell proliferation. A number of protein abundance changes persisted beyond the return of gross physiologic TA function. These findings represent the first report of BoNT induced changes in any skeletal muscle proteome, and reinforce the utility of applying proteomic tools to the study of system-wide biological processes in normal and perturbed TA muscle function. PMID:18442174

  13. Muscle fat-fraction and mapping in Duchenne muscular dystrophy: evaluation of disease distribution and correlation with clinical assessments. Preliminary experience.

    PubMed

    Gaeta, Michele; Messina, Sonia; Mileto, Achille; Vita, Gian Luca; Ascenti, Giorgio; Vinci, Sergio; Bottari, Antonio; Vita, Giuseppe; Settineri, Nicola; Bruschetta, Daniele; Racchiusa, Sergio; Minutoli, Fabio

    2012-08-01

    To examine the usefulness of dual-echo dual-flip angle spoiled gradient recalled (SPGR) magnetic resonance imaging (MRI) technique in quantifying muscle fat fraction (MFF) of pelvic and thighs muscles as a marker of disease severity in boys with Duchenne muscular dystrophy (DMD), by correlating MFF calculation with clinical assessments. We also tried to identify characteristic patterns of disease distribution. Twenty consecutive boys (mean age, 8.6 years ± 2.3 [standard deviation, SD]; age range, 5-15 years; median age, 9 years;) with DMD were evaluated using a dual-echo dual-flip angle SPGR MRI technique, calculating muscle fat fraction (MFF) of eight muscles in the pelvic girdle and thigh (gluteus maximus, adductor magnus, rectus femoris, vastus lateralis, vastus medialis, biceps femoris, semitendinosus, and gracilis). Color-coded parametric maps of MFF were also obtained. A neurologist who was blinded to the MRI findings performed the clinical assessments (patient age, Medical Research Council score, timed Gower score, time to run 10 m). The relationships between mean MFF and clinical assessments were investigated using Spearman's rho coefficient. Positive and negative correlations were evaluated and considered significant if the P value was < 0.05. The highest mean MFF was found in the gluteus maximus (mean, 46.3 % ± 24.5 SD), whereas the lowest was found in the gracilis muscle (mean, 2.7 % ± 4.7 SD). Mean MFF of the gluteus maximus was significantly higher than that of the other muscles (P < 0.01), except for the adductor magnus and biceps muscles. A significant positive correlation was found between the mean MFF of all muscles and the patients age (20 patients; P < 0.005), Medical Research Council score (19 patients; P < 0.001), timed Gower score (17 patients; P < 0.03), and time to run 10 m (20 patients; P < 0.001). A positive correlation was also found between the mean MFF of the gluteus maximus muscle and the

  14. Endoscopic laser thyroarytenoid myoneurectomy in patients with adductor spasmodic dysphonia: a pilot study on long-term outcome on voice quality.

    PubMed

    Tsuji, Domingos Hiroshi; Takahashi, Marystella Tomoe; Imamura, Rui; Hachiya, Adriana; Sennes, Luiz Ubirajara

    2012-09-01

    Adductor spasmodic dysphonia (ADSD) is a focal laryngeal dystonia, which compromises greatly the quality of life of the patients involved. It is a severe vocal disorder characterized by spasms of laryngeal muscles during speech, producing phonatory breaks, forced, strained and strangled voice. Its symptoms result from involuntary and intermittent contractions of thyroarytenoid muscle during speech, which causes vocal fold to strain, pressing each vocal fold against the other and increasing glottic resistance. Botulinum toxin injection remains the gold-standard treatment. However, as injections should be repeated periodically leading to voice quality instability, a more definitive procedure would be desirable. In this pilot study we report the long-term vocal quality results of endoscopic laser thyroarytenoid myoneurectomy. Prospective study. Surgery was performed in 15 patients (11 females and four males), aged between 29 and 73 years, diagnosed with ADSD. Voice Handicap Index (VHI) was obtained before and after surgery (median 31 months postoperatively). A significant improvement in VHI was observed after surgery, as compared with baseline values (P=0.001). The median and interquartile range for preoperative VHI was 99 and 13, respectively and 24 and 42, for postoperative VHI. Subjective improvement of voice as assessed by the patients showed median improvement of 80%. Because long-term follow-up showed significant improvement of voice quality, this innovative surgical technique seems a satisfactory alternative treatment of ADSD patients who seek a definite improvement of their condition. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  15. Groin injuries in sports medicine.

    PubMed

    Tyler, Timothy F; Silvers, Holly J; Gerhardt, Michael B; Nicholas, Stephen J

    2010-05-01

    An in-season groin injury may be debilitating for the athlete. Proper diagnosis and identification of the pathology are paramount in providing appropriate intervention. Furthermore, an adductor strain that is treated improperly can become chronic and career threatening. Any one of the 6 muscles of the adductor muscle group can be involved. The degree of injury can range from a minor strain (grade 1), where minimal playing time is lost, to a severe strain (grade 3), in which there is complete loss of muscle function. Persistent groin pain and muscle imbalance may lead to athletic pubalgia. Relevant studies were identified through a literature search of MEDLINE and the Cochrane database from 1990 to 2009, as well as a manual review of reference lists of identified sources. Ice hockey and soccer players seem particularly susceptible to adductor muscle strains. In professional ice hockey and soccer players throughout the world, approximately 10% to 11% of all injuries are groin strains. These injuries have been linked to hip muscle weakness, a previous injury to that area, preseason practice sessions, and level of experience. This injury may be prevented if these risk factors are addressed before each season. Despite the identification of risk factors and strengthening intervention for athletes, adductor strains continue to occur throughout sport. If groin pain persists, the possibility of athletic pubalgia needs to be explored, because of weakening or tears in the abdominal wall muscles. A diagnosis is confirmed by exclusion of other pathology.

  16. Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

    1995-01-01

    The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.

  17. Hoffmann's syndrome with unusually long duration: Report on clinical, laboratory and muscle imaging findings in two cases

    PubMed Central

    Nalini, Atchayaram; Govindaraju, C.; Kalra, Pramila; Kadukar, Prashanth

    2014-01-01

    Two adult men presented with the rare Hoffmann's syndrome (HS). Case 1: A 35-year-old male patient had progressive stiffness of lower limbs of 13 years and generalized muscle hypertrophy and myalgia of 3 years duration. Had periorbital edema, dry skin, generalized muscle hypertrophy and spastic dysarthria with hoarseness. Muscle power was normal. Jaw jerk and deep tendon reflexes were exaggerated. Case 2: A 24-year-old male patient presented with muscle hypertrophy from childhood, slowness in motor activities and hearing impairment. For 6 months, he had severe muscle pains, cramps and further increase in hypertrophy. He had yellow tinged, dry skin, hoarseness of voice, gross muscle hypertrophy and minimal weakness. Both had markedly elevated serum creatine kinase (CK) levels and high thyroid stimulating hormone, low free triiodothyronine and free thyroxine levels. Levothyroxine treatment demonstrated remarkable reduction in muscle bulk at 2 months in both and no symptoms at 6 months. Magnetic resonance imaging of lower limbs in both cases revealed almost identical features with involvement of the muscles of posterior and adductor compartment of thighs and posterior and lateral compartments of the legs. Differential diagnosis of long duration muscle pseudohypertrophy and elevated CK levels should include HS. PMID:25024579

  18. Motor evoked responses from the thigh muscles to the stimulation of the upper limb nerves in patients with late poliomyelitis.

    PubMed

    Ertekin, Cumhur; On, Arzu Yagiz; Kirazli, Yeşim; Kurt, Tülay; Gürgör, Nevin

    2002-04-01

    To demonstrate a clear-cut M response recorded from the severely affected thigh muscles to the stimulation of the upper limb nerves in a serial of patients with late poliomyelitis. Fifteen patients with late poliomyelitis, 7 patients with spinal cord disorders and 11 control subjects were included. Evoked muscle responses were investigated in quadriceps femoris and/or thigh adductor muscles to the stimulation of the brachial plexus, median and ulnar nerves. Evoked muscle responses were obtained from the thigh muscles in all 12 late polio patients with proximal lower extremity involvement. The response could not be recorded from the thigh muscles neither in the 3 polio patients with upper extremity involvement nor in the healthy control subjects and in patients with other spinal cord disorders of anterior horn cell. It is proposed that the electrical stimulation of the arm nerves produce interlimb descending muscle responses in the severely affected atrophic thigh muscles of the patients with late polio. This finding suggests that there might be a focal and/or specific loss of inhibitory interneurons between injured and normal motor neurons and increased facilitatory synaptic action at the end of long propriospinal descending fibers in the case of late poliomyelitis.

  19. Leg Muscle Involvement in Facioscapulohumeral Muscular Dystrophy: Comparison between Facioscapulohumeral Muscular Dystrophy Types 1 and 2.

    PubMed

    Mair, Dorothea; Huegens-Penzel, Monika; Kress, Wolfram; Roth, Christian; Ferbert, Andreas

    2017-01-01

    Facioscapulohumeral muscular dystrophy (FSHD) presents with 2 genetically distinct types. We describe for the first time the MRI patterns of leg muscle involvement in type 2 and compare it with type 1. The intramuscular fat content was assessed on lower extremity axial T1-weighted MRI scans in 6 FSHD1 and 5 FSHD2 patients. Overall, the muscle involvement profile did not differ substantially between FSHD1 and FSHD2. In the thigh, the dorsomedial compartment including the semimembranosus, semitendinosus and adductor magnus was the most affected. The quadriceps was mostly spared, but isolated involvement of the rectus femoris was common. Fat infiltration in the distal soleus and the medial gastrocnemius with sparing of the lateral gastrocnemius was a common finding; involvement of the tibialis anterior was less frequent. A proximal-to-distal increase in fat content was frequently present in some muscles. Muscle involvement appears to be independent of type, confirming a similar pathophysiological pathway in FSHD1 and FSHD2. © 2016 S. Karger AG, Basel.

  20. Influence and interactions of laryngeal adductors and cricothyroid muscles on fundamental frequency and glottal posture control

    PubMed Central

    Chhetri, Dinesh K.; Neubauer, Juergen; Sofer, Elazar; Berry, David A.

    2014-01-01

    The interactions of the intrinsic laryngeal muscles (ILMs) in controlling fundamental frequency (F0) and glottal posture remain unclear. In an in vivo canine model, three sets of intrinsic laryngeal muscles—the thyroarytenoid (TA), cricothyroid (CT), and lateral cricoarytenoid plus interarytenoid (LCA/IA) muscle complex—were independently and accurately stimulated in a graded manner using distal laryngeal nerve stimulation. Graded neuromuscular stimulation was used to independently activate these paired intrinsic laryngeal muscles over a range from threshold to maximal activation, to produce 320 distinct laryngeal phonatory postures. At phonation onset these activation conditions were evaluated in terms of their vocal fold strain, glottal width at the vocal processes, fundamental frequency (F0), subglottic pressure, and airflow. F0 ranged from 69 to 772 Hz and clustered into chest-like and falsetto-like groups. CT activation was always required to raise F0, but could also lower F0 at low TA and LCA/IA activation levels. Increasing TA activation first increased then decreased F0 in all CT and LCA/IA activation conditions. Increasing TA activation also facilitated production of high F0 at a lower onset pressure. Independent control of membranous (TA) and cartilaginous (LCA/IA) glottal closure enabled multiple pathways for F0 control via changes in glottal posture. PMID:25235003

  1. Clinical Muscle Testing Compared with Whole-Body Magnetic Resonance Imaging in Facio-scapulo-humeral Muscular Dystrophy.

    PubMed

    Regula, J U; Jestaedt, L; Jende, F; Bartsch, A; Meinck, H-M; Weber, M-A

    2016-12-01

    The objective of this study was to evaluate the clinical usefulness of whole-body magnetic resonance imaging (MRI) in facio-scapulo-humeral muscular dystrophy (FSHD). In 20 patients with genetically proven FSHD1, we prospectively assessed muscular involvement and correlated the results of semi-quantitative manual muscle testing and other parameters such as disease duration, creatine kinase (CK) levels and repeat length of the D4Z4 locus with whole-body MRI. Clinical muscle testing revealed the trapezius, pectoralis and infraspinatus as the most severely affected muscles in the shoulder, and the knee flexors and gluteus medius in the hip girdle. MRI revealed the trapezius and serratus anterior muscles in the shoulder, and the hamstrings and adductor muscles in the hip girdle, as the most severely affected muscle groups. Overall, degrees of fatty degeneration on MRI scans correlated significantly with clinical weakness. Moreover, we could detect clear affection of the trunk muscles. Corresponding to earlier reports, asymmetric involvement was frequent in both clinical examination and MRI scoring. Moreover, MRI revealed inhomogeneous muscle degeneration in a considerable proportion of both, muscles and patients. Both clinical and MRI scores significantly correlated to disease duration, but not to fragment size or CK levels. Fatty degeneration in whole-body MRI correlates well to clinical muscle testing of the extremities but gives more information on deeper or trunk muscles. It shows structural changes in muscular disorders and may become an excellent tool for assessment of muscle involvement and follow-up studies.

  2. Groin Injuries in Sports Medicine

    PubMed Central

    Tyler, Timothy F.; Silvers, Holly J.; Gerhardt, Michael B.; Nicholas, Stephen J.

    2010-01-01

    Context: An in-season groin injury may be debilitating for the athlete. Proper diagnosis and identification of the pathology are paramount in providing appropriate intervention. Furthermore, an adductor strain that is treated improperly can become chronic and career threatening. Any one of the 6 muscles of the adductor muscle group can be involved. The degree of injury can range from a minor strain (grade 1), where minimal playing time is lost, to a severe strain (grade 3), in which there is complete loss of muscle function. Persistent groin pain and muscle imbalance may lead to athletic pubalgia. Evidence Acquisition: Relevant studies were identified through a literature search of MEDLINE and the Cochrane database from 1990 to 2009, as well as a manual review of reference lists of identified sources. Results: Ice hockey and soccer players seem particularly susceptible to adductor muscle strains. In professional ice hockey and soccer players throughout the world, approximately 10% to 11% of all injuries are groin strains. These injuries have been linked to hip muscle weakness, a previous injury to that area, preseason practice sessions, and level of experience. This injury may be prevented if these risk factors are addressed before each season. Conclusion: Despite the identification of risk factors and strengthening intervention for athletes, adductor strains continue to occur throughout sport. If groin pain persists, the possibility of athletic pubalgia needs to be explored, because of weakening or tears in the abdominal wall muscles. A diagnosis is confirmed by exclusion of other pathology. PMID:23015943

  3. Assessment of bioelectrical activity of synergistic muscles during pelvic floor muscles activation in postmenopausal women with and without stress urinary incontinence: a preliminary observational study

    PubMed Central

    Ptaszkowski, Kuba; Paprocka-Borowicz, Małgorzata; Słupska, Lucyna; Bartnicki, Janusz; Dymarek, Robert; Rosińczuk, Joanna; Heimrath, Jerzy; Dembowski, Janusz; Zdrojowy, Romuald

    2015-01-01

    Objective Muscles such as adductor magnus (AM), gluteus maximus (GM), rectus abdominis (RA), and abdominal external and internal oblique muscles are considered to play an important role in the treatment of stress urinary incontinence (SUI), and the relationship between contraction of these muscles and pelvic floor muscles (PFM) has been established in previous studies. Synergistic muscle activation intensifies a woman’s ability to contract the PFM. In some cases, even for continent women, it is not possible to fully contract their PFM without involving the synergistic muscles. The primary aim of this study was to assess the surface electromyographic activity of synergistic muscles to PFM (SPFM) during resting and functional PFM activation in postmenopausal women with and without SUI. Materials and methods This study was a preliminary, prospective, cross-sectional observational study and included volunteers and patients who visited the Department and Clinic of Urology, University Hospital in Wroclaw, Poland. Forty-two patients participated in the study and were screened for eligibility criteria. Thirty participants satisfied the criteria and were categorized into two groups: women with SUI (n=16) and continent women (n=14). The bioelectrical activity of PFM and SPFM (AM, RA, GM) was recorded with a surface electromyographic instrument in a standing position during resting and functional PFM activity. Results Bioelectrical activity of RA was significantly higher in the incontinent group than in the continent group. These results concern the RA activity during resting and functional PFM activity. The results for other muscles showed no significant difference in bioelectrical activity between groups. Conclusion In women with SUI, during the isolated activation of PFM, an increased synergistic activity of RA muscle was observed; however, this activity was not observed in asymptomatic women. This may indicate the important accessory contribution of these muscles in the

  4. Assessment of bioelectrical activity of synergistic muscles during pelvic floor muscles activation in postmenopausal women with and without stress urinary incontinence: a preliminary observational study.

    PubMed

    Ptaszkowski, Kuba; Paprocka-Borowicz, Małgorzata; Słupska, Lucyna; Bartnicki, Janusz; Dymarek, Robert; Rosińczuk, Joanna; Heimrath, Jerzy; Dembowski, Janusz; Zdrojowy, Romuald

    2015-01-01

    Muscles such as adductor magnus (AM), gluteus maximus (GM), rectus abdominis (RA), and abdominal external and internal oblique muscles are considered to play an important role in the treatment of stress urinary incontinence (SUI), and the relationship between contraction of these muscles and pelvic floor muscles (PFM) has been established in previous studies. Synergistic muscle activation intensifies a woman's ability to contract the PFM. In some cases, even for continent women, it is not possible to fully contract their PFM without involving the synergistic muscles. The primary aim of this study was to assess the surface electromyographic activity of synergistic muscles to PFM (SPFM) during resting and functional PFM activation in postmenopausal women with and without SUI. This study was a preliminary, prospective, cross-sectional observational study and included volunteers and patients who visited the Department and Clinic of Urology, University Hospital in Wroclaw, Poland. Forty-two patients participated in the study and were screened for eligibility criteria. Thirty participants satisfied the criteria and were categorized into two groups: women with SUI (n=16) and continent women (n=14). The bioelectrical activity of PFM and SPFM (AM, RA, GM) was recorded with a surface electromyographic instrument in a standing position during resting and functional PFM activity. Bioelectrical activity of RA was significantly higher in the incontinent group than in the continent group. These results concern the RA activity during resting and functional PFM activity. The results for other muscles showed no significant difference in bioelectrical activity between groups. In women with SUI, during the isolated activation of PFM, an increased synergistic activity of RA muscle was observed; however, this activity was not observed in asymptomatic women. This may indicate the important accessory contribution of these muscles in the mechanism of continence.

  5. The effect of low back pain on trunk muscle size/function and hip strength in elite football (soccer) players.

    PubMed

    Hides, Julie A; Oostenbroek, Tim; Franettovich Smith, Melinda M; Mendis, M Dilani

    2016-12-01

    Low back pain (LBP) is a common problem in football (soccer) players. The effect of LBP on the trunk and hip muscles in this group is unknown. The relationship between LBP and trunk muscle size and function in football players across the preseason was examined. A secondary aim was to assess hip muscle strength. Twenty-five elite soccer players participated in the study, with assessments conducted on 23 players at both the start and end of the preseason. LBP was assessed with questionnaires and ultrasound imaging was used to assess size and function of trunk muscles at the start and end of preseason. Dynamometry was used to assess hip muscle strength at the start of the preseason. At the start of the preseason, 28% of players reported the presence of LBP and this was associated with reduced size of the multifidus, increased contraction of the transversus abdominis and multifidus muscles. LBP decreased across the preseason, and size of the multifidus muscle improved over the preseason. Ability to contract the abdominal and multifidus muscles did not alter across the preseason. Asymmetry in hip adductor and abductor muscle strength was found between players with and without LBP. Identifying modifiable factors in players with LBP may allow development of more targeted preseason rehabilitation programmes.

  6. Test-Retest Reliability of Innovated Strength Tests for Hip Muscles

    PubMed Central

    Meyer, Christophe; Corten, Kristoff; Wesseling, Mariska; Peers, Koen; Simon, Jean-Pierre; Jonkers, Ilse; Desloovere, Kaat

    2013-01-01

    The burden of hip muscles weakness and its relation to other impairments has been well documented. It is therefore a pre-requisite to have a reliable method for clinical assessment of hip muscles function allowing the design and implementation of a proper strengthening program. Motor-driven dynamometry has been widely accepted as the gold-standard for lower limb muscle strength assessment but is mainly related to the knee joint. Studies focusing on the hip joint are less exhaustive and somewhat discrepant with regard to optimal participants position, consequently influencing outcome measures. Thus, we aimed to develop a standardized test setup for the assessment of hip muscles strength, i.e. flexors/extensors and abductors/adductors, with improved participant stability and to define its psychometric characteristics. Eighteen participants performed unilateral isokinetic and isometric contractions of the hip muscles in the sagittal and coronal plane at two separate occasions. Peak torque and normalized peak torque were measured for each contraction. Relative and absolute measures of reliability were calculated using the intraclass correlation coefficient and standard error of measurement, respectively. Results from this study revealed higher levels of between-day reliability of isokinetic/isometric hip abduction/flexion peak torque compared to existing literature. The least reliable measures were found for hip extension and adduction, which could be explained by a less efficient stabilization technique. Our study additionally provided a first set of reference normalized data which can be used in future research. PMID:24260550

  7. Musculoskeletal Geometry, Muscle Architecture and Functional Specialisations of the Mouse Hindlimb.

    PubMed

    Charles, James P; Cappellari, Ornella; Spence, Andrew J; Hutchinson, John R; Wells, Dominic J

    2016-01-01

    Mice are one of the most commonly used laboratory animals, with an extensive array of disease models in existence, including for many neuromuscular diseases. The hindlimb is of particular interest due to several close muscle analogues/homologues to humans and other species. A detailed anatomical study describing the adult morphology is lacking, however. This study describes in detail the musculoskeletal geometry and skeletal muscle architecture of the mouse hindlimb and pelvis, determining the extent to which the muscles are adapted for their function, as inferred from their architecture. Using I2KI enhanced microCT scanning and digital segmentation, it was possible to identify 39 distinct muscles of the hindlimb and pelvis belonging to nine functional groups. The architecture of each of these muscles was determined through microdissections, revealing strong architectural specialisations between the functional groups. The hip extensors and hip adductors showed significantly stronger adaptations towards high contraction velocities and joint control relative to the distal functional groups, which exhibited larger physiological cross sectional areas and longer tendons, adaptations for high force output and elastic energy savings. These results suggest that a proximo-distal gradient in muscle architecture exists in the mouse hindlimb. Such a gradient has been purported to function in aiding locomotor stability and efficiency. The data presented here will be especially valuable to any research with a focus on the architecture or gross anatomy of the mouse hindlimb and pelvis musculature, but also of use to anyone interested in the functional significance of muscle design in relation to quadrupedal locomotion.

  8. Comparative functional anatomy of hindlimb muscles and bones with reference to aquatic adaptation of the sea otter.

    PubMed

    Mori, Kent; Suzuki, Satoshi; Koyabu, Daisuke; Kimura, Junpei; Han, Sung-Yong; Endo, Hideki

    2015-05-01

    Although the sea otter (Enhydra lutris) is a complete aquatic species, spending its entire life in the ocean, it has been considered morphologically to be a semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and functional adaptations of E. lutris in comparison to other Mustelidae species. We compared muscle mass and bone measurements of five Mustelidae species: the sea otter, Eurasian river otter (Lutra lutra), American mink (Neovison vison), Japanese weasel (Mustela itatsi) and Siberian weasel (M. sibirica). In comparison with the other 4 species, E. lutris possessed significantly larger gluteus, popliteus and peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle of E. lutris were fused with those of the tensor fasciae latae muscle and gluteofemoralis muscles, and they may play a role in femur abduction. These results suggest that E. lutris uses the abducted femur, medially rotated crus, eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful propulsion generator. Therefore, we conclude that E. lutris is a complete aquatic animal, possessing differences in the proportions of the hindlimb muscles compared with those in other semi-aquatic and terrestrial mustelids.

  9. Comparative functional anatomy of hindlimb muscles and bones with reference to aquatic adaptation of the sea otter

    PubMed Central

    MORI, Kent; SUZUKI, Satoshi; KOYABU, Daisuke; KIMURA, Junpei; HAN, Sung-Yong; ENDO, Hideki

    2015-01-01

    Although the sea otter (Enhydra lutris) is a complete aquatic species, spending its entire life in the ocean, it has been considered morphologically to be a semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and functional adaptations of E. lutris in comparison to other Mustelidae species. We compared muscle mass and bone measurements of five Mustelidae species: the sea otter, Eurasian river otter (Lutra lutra), American mink (Neovison vison), Japanese weasel (Mustela itatsi) and Siberian weasel (M. sibirica). In comparison with the other 4 species, E. lutris possessed significantly larger gluteus, popliteus and peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle of E. lutris were fused with those of the tensor fasciae latae muscle and gluteofemoralis muscles, and they may play a role in femur abduction. These results suggest that E. lutris uses the abducted femur, medially rotated crus, eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful propulsion generator. Therefore, we conclude that E. lutris is a complete aquatic animal, possessing differences in the proportions of the hindlimb muscles compared with those in other semi-aquatic and terrestrial mustelids. PMID:25715875

  10. Relative Contributions of Adductor Canal Block and Intrathecal Morphine to Analgesia and Functional Recovery After Total Knee Arthroplasty: A Randomized Controlled Trial.

    PubMed

    Biswas, Abhijit; Perlas, Anahi; Ghosh, Meela; Chin, KiJinn; Niazi, Ahtsham; Pandher, Barjind; Chan, Vincent

    2018-02-01

    Effective postoperative analgesia may enhance early rehabilitation after orthopedic surgery. This randomized double-blind trial investigates the relative contributions of adductor canal block and low-dose intrathecal morphine (ITM) to postoperative analgesia and functional recovery after total knee arthroplasty. Two-hundred one patients undergoing elective unilateral total knee arthroplasty under spinal anesthesia were randomized to 3 groups. All patients received standardized intraoperative local infiltration analgesia and postoperative oral analgesics. Patients in group 1 received a "sham" adductor canal block with 30 mL of normal saline. Patients in group 2 received an adductor canal block with 30 mL of ropivacaine 0.5% with 1:400,000 epinephrine, whereas patients in group 3 received the adductor canal block with the active drug and 100 μg of ITM. The primary outcome measure was the Timed Up and Go (TUG) test on the second postoperative day. Secondary outcomes included postoperative pain scores and opioid requirements, distance walked, time to hospital discharge, and self-reported functional outcomes at 3 months. All 3 groups had similar values of TUG test on postoperative day (POD) 2 (46 [36-62], 45 [33-61], and 52 [41-69]; P = 0.166) as well as other short-term and 3-month functional outcomes. Patients in group 3 showed a favorable analgesic profile as evidenced by 3 positive secondary outcomes. These positive outcomes were lower pain scores 12 hours postoperatively both at rest (4 [2-6.3], 4 [2.3-6], and 3 [1-4]; P = 0.007) and on movement (6 [4-8], 6 [3-8], and 4 [2-6]; P = 0.002), a lower incidence of "rescue" intravenous patient-controlled analgesia (42%, 34%, and 20%; P = 0.031), and the lowest cumulative opioid requirements for the first 48 hours postoperatively (86 ± 71, 68 ± 46, and 59 ± 39; P < 0.005, group 3 compared with group 1). Our data suggest that there is no difference in either the primary outcome of TUG test on POD 2, other immediate

  11. Abnormal motor cortex excitability during linguistic tasks in adductor-type spasmodic dysphonia.

    PubMed

    Suppa, A; Marsili, L; Giovannelli, F; Di Stasio, F; Rocchi, L; Upadhyay, N; Ruoppolo, G; Cincotta, M; Berardelli, A

    2015-08-01

    In healthy subjects (HS), transcranial magnetic stimulation (TMS) applied during 'linguistic' tasks discloses excitability changes in the dominant hemisphere primary motor cortex (M1). We investigated 'linguistic' task-related cortical excitability modulation in patients with adductor-type spasmodic dysphonia (ASD), a speech-related focal dystonia. We studied 10 ASD patients and 10 HS. Speech examination included voice cepstral analysis. We investigated the dominant/non-dominant M1 excitability at baseline, during 'linguistic' (reading aloud/silent reading/producing simple phonation) and 'non-linguistic' tasks (looking at non-letter strings/producing oral movements). Motor evoked potentials (MEPs) were recorded from the contralateral hand muscles. We measured the cortical silent period (CSP) length and tested MEPs in HS and patients performing the 'linguistic' tasks with different voice intensities. We also examined MEPs in HS and ASD during hand-related 'action-verb' observation. Patients were studied under and not-under botulinum neurotoxin-type A (BoNT-A). In HS, TMS over the dominant M1 elicited larger MEPs during 'reading aloud' than during the other 'linguistic'/'non-linguistic' tasks. Conversely, in ASD, TMS over the dominant M1 elicited increased-amplitude MEPs during 'reading aloud' and 'syllabic phonation' tasks. CSP length was shorter in ASD than in HS and remained unchanged in both groups performing 'linguistic'/'non-linguistic' tasks. In HS and ASD, 'linguistic' task-related excitability changes were present regardless of the different voice intensities. During hand-related 'action-verb' observation, MEPs decreased in HS, whereas in ASD they increased. In ASD, BoNT-A improved speech, as demonstrated by cepstral analysis and restored the TMS abnormalities. ASD reflects dominant hemisphere excitability changes related to 'linguistic' tasks; BoNT-A returns these excitability changes to normal. © 2015 Federation of European Neuroscience Societies and John

  12. Microarray Analysis Gene Expression Profiles in Laryngeal Muscle After Recurrent Laryngeal Nerve Injury.

    PubMed

    Bijangi-Vishehsaraei, Khadijeh; Blum, Kevin; Zhang, Hongji; Safa, Ahmad R; Halum, Stacey L

    2016-03-01

    The pathophysiology of recurrent laryngeal nerve (RLN) transection injury is rare in that it is characteristically followed by a high degree of spontaneous reinnervation, with reinnervation of the laryngeal adductor complex (AC) preceding that of the abducting posterior cricoarytenoid (PCA) muscle. Here, we aim to elucidate the differentially expressed myogenic factors following RLN injury that may be at least partially responsible for the spontaneous reinnervation. F344 male rats underwent RLN injury (n = 12) or sham surgery (n = 12). One week after RLN injury, larynges were harvested following euthanasia. The mRNA was extracted from PCA and AC muscles bilaterally, and microarray analysis was performed using a full rat genome array. Microarray analysis of denervated AC and PCA muscles demonstrated dramatic differences in gene expression profiles, with 205 individual probes that were differentially expressed between the denervated AC and PCA muscles and only 14 genes with similar expression patterns. The differential expression patterns of the AC and PCA suggest different mechanisms of reinnervation. The PCA showed the gene patterns of Wallerian degeneration, while the AC expressed the gene patterns of reinnervation by adjacent axonal sprouting. This finding may reveal important therapeutic targets applicable to RLN and other peripheral nerve injuries. © The Author(s) 2015.

  13. Laryngeal reinnervation for bilateral vocal fold paralysis.

    PubMed

    Marina, Mat B; Marie, Jean-Paul; Birchall, Martin A

    2011-12-01

    Laryngeal reinnervation for bilateral vocal fold paralysis (BVFP) patients is a promising technique to achieve good airway, although preserving a good quality of voice. On the other hand, the procedure is not simple. This review explores the recent literature on surgical technique and factors that may contribute to the success. Research and literature in this area are limited due to variability and complexity of the nerve supply. The posterior cricoarytenoid (PCA) muscle also receives nerve supply from the interarytenoid branch. Transection of this nerve at the point between interarytenoid and PCA branch may prevent aberrant reinnervation of adductor nerve axons to the PCA muscle. A varying degree of regeneration of injured recurrent laryngeal nerves (RLN) in humans of more than 6 months confirms subclinical reinnervation, which may prevent denervation-induced atrophy. Several promising surgical techniques have been developed for bilateral selective reinnervation for BVFP patients. This involves reinnervation of the abductor and adductor laryngeal muscles. The surgical technique aims at reinnervating the PCA muscle to trigger abduction during the respiratory cycle and preservation of good voice by strengthening the adductor muscles as well as prevention of laryngeal synkinesis.

  14. Musculoskeletal anatomy of the pelvic fin of Polypterus: implications for phylogenetic distribution and homology of pre- and postaxial pelvic appendicular muscles.

    PubMed

    Molnar, Julia L; Johnston, Peter S; Esteve-Altava, Borja; Diogo, Rui

    2017-04-01

    As a member of the most basal clade of extant ray-finned fishes (actinopterygians) and of one of the most basal clades of osteichthyans (bony fishes + tetrapods), Polypterus can provide insights into the ancestral anatomy of both ray-finned and lobe-finned fishes, including those that gave rise to tetrapods. The pectoral fin of Polypterus has been well described but, surprisingly, neither the bones nor the muscles of the pelvic fin are well known. We stained and dissected the pelvic fin of Polypterus senegalus and Polypterus delhezi to offer a detailed description of its musculoskeletal anatomy. In addition to the previously described adductor and abductor muscles, we found preaxial and postaxial muscles similar to those in the pectoral fin of members of this genus. The presence of pre- and postaxial muscles in both the pectoral and pelvic fins of Polypterus, combined with recent descriptions of similar muscles in the lobe-finned fishes Latimeria and Neoceratodus, suggests that they were present in the most recent common ancestor of bony fishes. These results have crucial implications for the evolution of appendicular muscles in both fish and tetrapods. © 2016 Anatomical Society.

  15. Magnetic resonance imaging phenotyping of Becker muscular dystrophy.

    PubMed

    Faridian-Aragh, Neda; Wagner, Kathryn R; Leung, Doris G; Carrino, John A

    2014-12-01

    There is little information on magnetic resonance imaging (MRI) phenotypes of Becker muscular dystrophy (BMD). This study presents the MRI phenotyping of the upper and lower extremities of a large cohort of BMD patients. In this retrospective study, MRI images of 33 BMD subjects were evaluated for severity, distribution, and symmetry of involvement. Teres major, triceps long head, biceps brachii long head, gluteus maximus, gluteus medius, vasti, adductor longus, adductor magnus, semitendinosus, semimembranosus, and biceps femoris muscles showed the highest severity and frequency of involvement. All analyzed muscles had a high frequency of symmetric involvement. There was significant variability of involvement between muscles within some muscle groups, most notably the arm abductors, posterior arm muscles, medial thigh muscles, and lateral hip rotators. This study showed a distinctive pattern of involvement of extremity muscles in BMD subjects. © 2014 Wiley Periodicals, Inc.

  16. Voice tuning with new instruments for type II thyroplasty in the treatment of adductor spasmodic dysphonia.

    PubMed

    Sanuki, Tetsuji; Yumoto, Eiji; Toya, Yutaka; Kumai, Yoshihiko

    2016-10-01

    Adductor spasmodic dysphonia is a rare voice disorder characterized by strained and strangled voice quality with intermittent phonatory breaks and adductory vocal fold spasms. Type II thyroplasty differs from previous treatments in that this surgery does not involve any surgical intervention into the laryngeal muscle, nerve or vocal folds. Type II thyroplasty intervenes in the thyroid cartilage, which is unrelated to the lesion. This procedure, conducted with the aim of achieving lateralization of the vocal folds, requires utmost surgical caution due to the extreme delicacy of the surgical site, critically sensitive adjustment, and difficult procedures to maintain the incised cartilages at a correct position. During surgery, the correct separation of the incised cartilage edges with voice monitoring is the most important factor determining surgical success and patient satisfaction. We designed new surgical instruments: a thyroid cartilage elevator for undermining the thyroid cartilage, and spacer devices to gauge width while performing voice monitoring. These devices were designed to prevent surgical complications, and to aid in selecting the optimal size of titanium bridges while temporally maintaining a separation during voice monitoring. We designed new surgical instruments, including a thyroid cartilage elevator and spacer devices. Precise surgical procedures and performing voice tuning during surgery with the optimal separation width of the thyroid cartilage are key points for surgical success. We introduce the technique of voice tuning using these surgical tools in order to achieve a better outcome with minimal surgical complications. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. The potential of digital dental radiography in recording the adductor sesamoid and the MP3 stages.

    PubMed

    Abdel-Kader, H M

    1999-12-01

    The current study was undertaken to evaluate the reliability of using a recent advance in clinical radiographic technique, digital dental radiography, in recording two growth indicators: the adductor sesamoid and MP3 stages. With an exposure time five times less than that used in the conventional approach, this method shows greatest flexibility in providing a high quality digitized radiographic images of the two growth indicators under investigation. Refereed Paper

  18. Blood pressure and the contractility of a human leg muscle.

    PubMed

    Luu, Billy L; Fitzpatrick, Richard C

    2013-11-01

    These studies investigate the relationships between perfusion pressure, force output and pressor responses for the contracting human tibialis anterior muscle. Eight healthy adults were studied. Changing the height of tibialis anterior relative to the heart was used to control local perfusion pressure. Electrically stimulated tetanic force output was highly sensitive to physiological variations in perfusion pressure showing a proportionate change in force output of 6.5% per 10 mmHg. This perfusion-dependent change in contractility begins within seconds and is reversible with a 53 s time constant, demonstrating a steady-state equilibrium between contractility and perfusion pressure. These stimulated contractions did not produce significant cardiovascular responses, indicating that the muscle pressor response does not play a major role in cardiovascular regulation at these workloads. Voluntary contractions at forces that would require constant motor drive if perfusion pressure had remained constant generated a central pressor response when perfusion pressure was lowered. This is consistent with a larger cortical drive being required to compensate for the lost contractility with lower perfusion pressure. The relationship between contractility and perfusion for this large postural muscle was not different from that of a small hand muscle (adductor pollicis) and it responded similarly to passive peripheral and active central changes in arterial pressure, but extended over a wider operating range of pressures. If we consider that, in a goal-oriented motor task, muscle contractility determines central motor output and the central pressor response, these results indicate that muscle would fatigue twice as fast without a pressor response. From its extent, timing and reversibility we propose a testable hypothesis that this change in contractility arises through contraction- and perfusion-dependent changes in interstitial K(+) concentration.

  19. Pm-miR-133 hosting in one potential lncRNA regulates RhoA expression in pearl oyster Pinctada martensii.

    PubMed

    Zheng, Zhe; Huang, RongLian; Tian, RongRong; Jiao, Yu; Du, Xiaodong

    2016-10-15

    Long non-coding RNAs (LncRNAs) are abundant in the genome of higher forms of eukaryotes and implicated in regulating the diversity of biological processes partly because they host microRNAs (miRNAs), which are repressors of target gene expression. In vertebrates, miR-133 regulates the differentiation and proliferation of cardiac and skeletal muscles. Pinctada martensii miR-133 (pm-miR-133) was identified in our previous research through Solexa deep sequencing. In the present study, the precise sequence of mature pm-miR-133 was validated through miR-RACE. Stem loop qRT-PCR analysis demonstrated that mature pm-miR-133 was constitutively expressed in the adductor muscle, gonad, hepatopancreas, mantle, foot, and gill of P. martensii. Among these tissues, the adductor muscle exhibited the highest pm-miR-133 expression. Target analysis indicated that pm-RhoA was the potential regulatory target of pm-miR-133. Bioinformatics analyses revealed that a potential LncRNA (designated as Lnc133) with a mature pm-miR-133 could generate a hairpin structure that was highly homologous to that of Lottia gigantea. Lnc133 was also highly expressed in the adductor muscle, gill, hepatopancreas, and gonad. Phylogenetic analysis further showed that the miR-133s derived from chordate and achordate were separated into two classes. Therefore, Lnc133 hosting pm-miR-133 could be involved in regulating the cell proliferation of adductor muscles by targeting pm-RhoA. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Neuromuscular Characteristics of Individuals Displaying Excessive Medial Knee Displacement

    PubMed Central

    Padua, Darin A.; Bell, David R.; Clark, Micheal A.

    2012-01-01

    Context Knee-valgus motion is a potential risk factor for certain lower extremity injuries, including anterior cruciate ligament injury and patellofemoral pain. Identifying neuromuscular characteristics associated with knee-valgus motion, such as hip and lower leg muscle activation, may improve our ability to prevent lower extremity injuries. Objective We hypothesized that hip and lower leg muscle-activation amplitude would differ among individuals displaying knee valgus (medial knee displacement) during a double-legged squat compared with those who did not display knee valgus. We further suggested that the use of a heel lift would alter lower leg muscle activation and frontal-plane knee motion in those demonstrating medial knee displacement. Design Descriptive laboratory study. Setting Research laboratory. Patients or Other Participants A total of 37 healthy participants were assigned to the control (n = 19) or medial-knee-displacement (n = 18) group based on their double-legged squat performance. Main Outcome Measure(s) Muscle-activation amplitude for the gluteus maximus, gluteus medius, adductor magnus, medial and lateral gastrocnemius, and tibialis anterior was measured during 2 double-legged squat tasks. The first task consisted of performing a double-legged squat without a heel lift; the second consisted of performing a double-legged squat task with a 2-in (5.08-cm) lift under the heels. Results Muscle-activation amplitude for the hip adductor, gastrocnemius, and tibialis anterior was greater in those who displayed knee valgus than in those who did not (P < .05). Also, use of heel lifts resulted in decreased activation of the gluteus maximus, hip adductor, gastrocnemius, and tibialis anterior muscles (P < .05). Use of heel lifts also eliminated medially directed frontal-plane knee motion in those displaying medial knee displacement. Conclusions Medial knee displacement during squatting tasks appears to be associated with increased hip-adductor activation and

  1. Fiber-type susceptibility to eccentric contraction-induced damage of hindlimb-unloaded rat AL muscles

    NASA Technical Reports Server (NTRS)

    Vijayan, K.; Thompson, J. L.; Norenberg, K. M.; Fitts, R. H.; Riley, D. A.

    2001-01-01

    Slow oxidative (SO) fibers of the adductor longus (AL) were predominantly damaged during voluntary reloading of hindlimb unloaded (HU) rats and appeared explainable by preferential SO fiber recruitment. The present study assessed damage after eliminating the variable of voluntary recruitment by tetanically activating all fibers in situ through the motor nerve while applying eccentric (lengthening) or isometric contractions. Muscles were aldehyde fixed and resin embedded, and semithin sections were cut. Sarcomere lesions were quantified in toluidine blue-stained sections. Fibers were typed in serial sections immunostained with antifast myosin and antitotal myosin (which highlights slow fibers). Both isometric and eccentric paradigms caused fatigue. Lesions occurred only in eccentrically contracted control and HU muscles. Fatigue did not cause lesions. HU increased damage because lesioned- fiber percentages within fiber types and lesion sizes were greater than control. Fast oxidative glycolytic (FOG) fibers were predominantly damaged. In no case did damaged SO fibers predominate. Thus, when FOG, SO, and hybrid fibers are actively lengthened in chronically unloaded muscle, FOG fibers are intrinsically more susceptible to damage than SO fibers. Damaged hybrid-fiber proportions ranged between these extremes.

  2. Treatment efficacy of electromyography versus fiberscopy-guided botulinum toxin injection in adductor spasmodic dysphonia patients: a prospective comparative study.

    PubMed

    Kim, Jae Wook; Park, Jae Hong; Park, Ki Nam; Lee, Seung Won

    2014-01-01

    This study prospectively evaluates and compares the treatment efficacy of botulinum toxin injection under electromyography guidance (EMG group) and percutaneous botulinum toxin injection under flexible fiberscopic guidance (fiberscopy group). Thirty patients with adductor spasmodic dysphonia (ADSD), who had never received treatment, were randomly allocated into EMG- or fiberscopy-guided botulinum toxin injections between March 2008 and February 2010. We assessed acoustic and aerodynamic voice parameters, and the voice handicap index (VHI) before injection and at 1, 3, and 6 months after injection. The mean total dosage of botulinum toxin was similar for both groups: 1.7 ± 0.5 U for the EMG group and 1.8 ± 0.4 U for the fiberscopy group (P > 0.05). There were no significant differences in outcomes between the two groups in either the duration of effectiveness or complications such as breathy voice and aspiration. Botulinum toxin injection under fiberscopic guidance is a viable alternative to EMG-guided botulinum toxin injection for the treatment of adductor spasmodic dysphonia when EMG equipment is unavailable.

  3. Treatment Efficacy of Electromyography versus Fiberscopy-Guided Botulinum Toxin Injection in Adductor Spasmodic Dysphonia Patients: A Prospective Comparative Study

    PubMed Central

    Kim, Jae Wook; Park, Jae Hong; Park, Ki Nam; Lee, Seung Won

    2014-01-01

    Introduction. This study prospectively evaluates and compares the treatment efficacy of botulinum toxin injection under electromyography guidance (EMG group) and percutaneous botulinum toxin injection under flexible fiberscopic guidance (fiberscopy group). Methods. Thirty patients with adductor spasmodic dysphonia (ADSD), who had never received treatment, were randomly allocated into EMG- or fiberscopy-guided botulinum toxin injections between March 2008 and February 2010. We assessed acoustic and aerodynamic voice parameters, and the voice handicap index (VHI) before injection and at 1, 3, and 6 months after injection. Results. The mean total dosage of botulinum toxin was similar for both groups: 1.7 ± 0.5 U for the EMG group and 1.8 ± 0.4 U for the fiberscopy group (P > 0.05). There were no significant differences in outcomes between the two groups in either the duration of effectiveness or complications such as breathy voice and aspiration. Conclusion. Botulinum toxin injection under fiberscopic guidance is a viable alternative to EMG-guided botulinum toxin injection for the treatment of adductor spasmodic dysphonia when EMG equipment is unavailable. PMID:25383369

  4. Considerations for initial dosing of botulinum toxin in treatment of adductor spasmodic dysphonia.

    PubMed

    Rosow, David E; Parikh, Punam; Vivero, Richard J; Casiano, Roy R; Lundy, Donna S

    2013-06-01

    To assess the effect on voice improvement and duration of breathiness based on initial dose of onabotulinum toxin A (BTX-A) in the management of adductor spasmodic dysphonia (SD) and to compare voice outcomes for initial bilaterally injected doses of 1.25 units (group A) vs 2.5 units (group B) of BTX-A. Case series with chart review of patients with adductor SD treated at a tertiary care facility from 1990 to 2011. Academic subspecialty laryngology practice. Demographic data (age and sex), voice rating, duration of voice improvement, and breathiness were evaluated and compared between groups A and B using the Student t test and χ(2) analysis. Of 478 patients identified, 305 (223 in group A, 82 in group B) patients met inclusion criteria. The average age was 56.2 years in group A and 57.4 years in group B (P = .5). The female to male ratio was 2.91 for group A vs 3.56 for group B (P = .61). Good voice outcomes (grade 3 or 4) were reported by 91% of group A patients vs 94% of group B (P = .75). The average duration of voice improvement was 99.7 days for group A and 108.3 days for group B (P = .54). The average duration of breathiness was 10.88 days for group A vs 15.42 days for group B (P = .02). Patients injected with 1.25 units bilaterally had a statistically significant shorter duration of breathiness without a statistically significant difference in clinical effectiveness or voice outcome. It is therefore recommended that a relatively low initial BTX-A dose be used with subsequent titration to achieve improved voice outcomes.

  5. Muscle fiber type specific induction of slow myosin heavy chain 2 gene expression by electrical stimulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crew, Jennifer R.; Falzari, Kanakeshwari; DiMario, Joseph X., E-mail: joseph.dimario@rosalindfranklin.edu

    Vertebrate skeletal muscle fiber types are defined by a broad array of differentially expressed contractile and metabolic protein genes. The mechanisms that establish and maintain these different fiber types vary throughout development and with changing functional demand. Chicken skeletal muscle fibers can be generally categorized as fast and fast/slow based on expression of the slow myosin heavy chain 2 (MyHC2) gene in fast/slow muscle fibers. To investigate the cellular and molecular mechanisms that control fiber type formation in secondary or fetal muscle fibers, myoblasts from the fast pectoralis major (PM) and fast/slow medial adductor (MA) muscles were isolated, allowed tomore » differentiate in vitro, and electrically stimulated. MA muscle fibers were induced to express the slow MyHC2 gene by electrical stimulation, whereas PM muscle fibers did not express the slow MyHC2 gene under identical stimulation conditions. However, PM muscle fibers did express the slow MyHC2 gene when electrical stimulation was combined with inhibition of inositol triphosphate receptor (IP3R) activity. Electrical stimulation was sufficient to increase nuclear localization of expressed nuclear-factor-of-activated-T-cells (NFAT), NFAT-mediated transcription, and slow MyHC2 promoter activity in MA muscle fibers. In contrast, both electrical stimulation and inhibitors of IP3R activity were required for these effects in PM muscle fibers. Electrical stimulation also increased levels of peroxisome-proliferator-activated receptor-{gamma} co-activator-1 (PGC-1{alpha}) protein in PM and MA muscle fibers. These results indicate that MA muscle fibers can be induced by electrical stimulation to express the slow MyHC2 gene and that fast PM muscle fibers are refractory to stimulation-induced slow MyHC2 gene expression due to fast PM muscle fiber specific cellular mechanisms involving IP3R activity.« less

  6. "Superior cleft sign" as a marker of rectus abdominus/adductor longus tear in patients with suspected sportsman's hernia.

    PubMed

    Murphy, Grainne; Foran, Paul; Murphy, Darra; Tobin, Oliver; Moynagh, Michael; Eustace, Stephen

    2013-06-01

    We describe a new imaging sign, the "superior cleft sign", identified at both symphysography and MRI, which should be used as a marker of rectus abdominis/adductor longus attachment tearing. A study population of 25 patients presenting with clinically suspected sportsman's hernia, who had undergone both symphysography and MRI of the groin were included for study. In each case, images were reviewed to determine the presence of a superior cleft, secondary cleft, and or both abnormalities. Images of all patients complaining of groin crease discomfort similar to sportsman's hernia revealed the presence of a superior cleft at the rectus abdominis/adductor longus attachment. This "superior cleft sign" correlated with the side of symptoms in each case, and, in contrast to the previously described secondary cleft along the inferior margin of the inferior pubic ramus, occurred parallel to the inferior margin of the superior pubic ramus. The presence of the "superior cleft sign" should be sought in addition to the previously described secondary cleft sign in sportspeople presenting with exercise-related groin pain or pubalgia. It should specifically be sought in patients referred with suspected sportsman's hernia.

  7. Blood pressure and the contractility of a human leg muscle

    PubMed Central

    Luu, Billy L; Fitzpatrick, Richard C

    2013-01-01

    These studies investigate the relationships between perfusion pressure, force output and pressor responses for the contracting human tibialis anterior muscle. Eight healthy adults were studied. Changing the height of tibialis anterior relative to the heart was used to control local perfusion pressure. Electrically stimulated tetanic force output was highly sensitive to physiological variations in perfusion pressure showing a proportionate change in force output of 6.5% per 10 mmHg. This perfusion-dependent change in contractility begins within seconds and is reversible with a 53 s time constant, demonstrating a steady-state equilibrium between contractility and perfusion pressure. These stimulated contractions did not produce significant cardiovascular responses, indicating that the muscle pressor response does not play a major role in cardiovascular regulation at these workloads. Voluntary contractions at forces that would require constant motor drive if perfusion pressure had remained constant generated a central pressor response when perfusion pressure was lowered. This is consistent with a larger cortical drive being required to compensate for the lost contractility with lower perfusion pressure. The relationship between contractility and perfusion for this large postural muscle was not different from that of a small hand muscle (adductor pollicis) and it responded similarly to passive peripheral and active central changes in arterial pressure, but extended over a wider operating range of pressures. If we consider that, in a goal-oriented motor task, muscle contractility determines central motor output and the central pressor response, these results indicate that muscle would fatigue twice as fast without a pressor response. From its extent, timing and reversibility we propose a testable hypothesis that this change in contractility arises through contraction- and perfusion-dependent changes in interstitial K+ concentration. PMID:24018946

  8. Muscle activation in young men during a lower limb aquatic resistance exercise with different devices.

    PubMed

    Borreani, Sebastien; Colado, Juan Carlos; Furio, Josep; Martin, Fernando; Tella, Víctor

    2014-05-01

    Little research has been reported on the effects of using different devices with resistance exercises in a water environment. This study compared muscular activation of lower extremity and core muscles during leg adduction performed at maximum velocity with drag and floating devices of different sizes. A total of 24 young men (mean age 23.20 ± 1.18 years) performed 3 repetitions of leg adduction at maximum velocity using 4 different devices (ie, large/small and drag/floating). The maximum amplitude of the electromyographic root mean square of the adductor longus, rectus abdominis, external oblique on the dominant side, external oblique on the nondominant side, and erector lumbar spinae were recorded. Electromyographic signals were normalized to the maximum voluntary isometric contraction (MVIC). Unexpectedly, no significant (P > 0.05) differences were found in the neuromuscular responses among the different devices used; the average activation of agonist muscle adequate for neuromuscular conditioning was 40.95% of MVIC. In addition, external oblique activation is greater on the contralateral side to stabilize the body (average, 151.74%; P < 0.05). Therefore, if maximum muscle activation is required, the kind of device is not relevant. Thus, the choice should be based on economic factors.

  9. The Role of Magnetic Resonance Imaging in Athletic Pubalgia and Core Muscle Injury.

    PubMed

    Coker, Dana J; Zoga, Adam C

    2015-08-01

    Magnetic resonance imaging (MRI) has become the standard of care imaging modality for a difficult, often misunderstood spectrum of musculoskeletal injury termed athletic pubalgia or core muscle injury. Armed with a dedicated noncontrast athletic pubalgia protocol and a late model phased array receiver coil, the musculoskeletal imager can play a great role in effective diagnosis and treatment planning for lesions, including osteitis pubis, midline pubic plate lesions, and rectus abdominis/adductor aponeurosis injury. Beyond these established patterns of MRI findings, there are many confounders and contributing pathologies about the pelvis in patients with activity related groin pain, including internal and periarticular derangements of the hip. The MRI is ideally suited to delineate the extent of expected injury and to identify the unexpected visceral and musculoskeletal lesions.

  10. Neuromuscular response of hip-spanning and low back muscles to medio-lateral foot center of pressure manipulation during gait.

    PubMed

    Solomonow-Avnon, Deborah; Levin, Daniel; Elboim-Gabyzon, Michal; Rozen, Nimrod; Peled, Eli; Wolf, Alon

    2016-06-01

    Footwear-generated medio-lateral foot center of pressure manipulation has been shown to have potential positive effects on gait parameters of hip osteoarthritis patients, ultimately reducing maximum joint reaction forces. The objective of this study was to investigate effects of medio-lateral foot center of pressure manipulation on muscle activity of hip-spanning and back muscles during gait in bilateral hip osteoarthritis patients. Foot center of pressure was shifted along the medio-lateral foot axis using a foot-worn biomechanical device allowing controlled center of pressure manipulation. Sixteen female bilateral hip osteoarthritis patients underwent electromyography analysis while walking in the device set to three parasagittal configurations: neutral (control), medial, and lateral. Seven hip-spanning muscles (Gluteus Medius, Gluteus Maximus, Tensor Fascia Latae, Rectus Femoris, Semitendinosis, Biceps Femoris, Adductor Magnus) and one back muscle (Erector Spinae) were analyzed. Magnitude and temporal parameters were calculated. The amplitude and temporal parameter varied significantly between foot center of pressure positions for 5 out of 8 muscles each for either the more or less symptomatic leg in at least one subphase of the gait cycle. Medio-lateral foot center of pressure manipulation significantly affects neuromuscular pattern of hip and back musculature during gait in female hip bilateral osteoarthritis patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Development of the muscles associated with the mandibular and hyoid arches in the Siberian sturgeon, Acipenser baerii (Acipenseriformes: Acipenseridae).

    PubMed

    Warth, Peter; Hilton, Eric J; Naumann, Benjamin; Olsson, Lennart; Konstantinidis, Peter

    2018-02-01

    The skeleton of the jaws and neurocranium of sturgeons (Acipenseridae) are connected only through the hyoid arch. This arrangement allows considerable protrusion and retraction of the jaws and is highly specialized among ray-finned fishes (Actinopterygii). To better understand the unique morphology and the evolution of the jaw apparatus in Acipenseridae, we investigated the development of the muscles of the mandibular and hyoid arches of the Siberian sturgeon, Acipenser baerii. We used a combination of antibody staining and formalin-induced fluorescence of tissues imaged with confocal microscopy and subsequent three-dimensional reconstruction. These data were analyzed to address the identity of previously controversial and newly discovered muscle portions. Our results indicate that the anlagen of the muscles in A. baerii develop similarly to those of other actinopterygians, although they differ by not differentiating into distinct muscles. This is exemplified by the subpartitioning of the m. adductor mandibulae as well as the massive m. protractor hyomandibulae, for which we found a previously undescribed portion in each. The importance of paedomorphosis for the evolution of Acipenseriformes has been discussed before and our results indicate that the muscles of the mandibular and the hyoid may be another example for heterochronic evolution. © 2017 Wiley Periodicals, Inc.

  12. EMG activity of hip and trunk muscles during deep-water running.

    PubMed

    Kaneda, Koichi; Sato, Daisuke; Wakabayashi, Hitoshi; Nomura, Takeo

    2009-12-01

    The present study used synchronized motion analysis to investigate the activity of hip and trunk muscles during deep-water running (DWR) relative to land walking (LW) and water walking (WW). Nine healthy men performed each exercise at self-determined slow, moderate, and fast paces, and surface electromyography was used to investigate activity of the adductor longus, gluteus maxima, gluteus medius, rectus abdominis, oblique externus abdominis, and erector spinae. The following kinematic parameters were calculated: the duration of one cycle, range of motion (ROM) of the hip joint, and absolute angles of the pelvis and trunk with respect to the vertical axis in the sagittal plane. The percentages of maximal voluntary contraction (%MVC) of each muscle were higher during DWR than during LW and WW. The %MVC of the erector spinae during WW increased concomitant with the pace increment. The hip joint ROMs were larger in DWR than in LW and WW. Forward inclinations of the trunk were apparent for DWR and fast-paced WW. The pelvis was inclined forward in DWR and WW. In conclusion, the higher-level activities during DWR are affected by greater hip joint motion and body inclinations with an unstable floating situation.

  13. Research-to-policy translation for prevention of disordered weight and shape control behaviors: A case example targeting dietary supplements sold for weight loss and muscle building.

    PubMed

    Austin, S Bryn; Yu, Kimberly; Tran, Alvin; Mayer, Beth

    2017-04-01

    New approaches to universal eating disorders prevention and interventions targeting macro-environmental change are greatly needed, and research-to-policy translation efforts hold promise for advancing both of these goals. This paper describes as a policy-translation case example an academic-community-government partnership of the Strategic Training Initiative for the Prevention of Eating Disorders, Multi-Service Eating Disorders Association, and the office of Massachusetts Representative Kay Khan, all based in Massachusetts, USA. The partnership's research-to-policy translation project focused on dietary supplements sold for weight loss and muscle building, which have been linked with serious injury and death in consumers. Youth and people of all ages with eating disorders and body dysmorphic disorder may be especially vulnerable to use these products due to deceptive promises of fast and safe weight loss and muscle gain. The research-to-policy translation project was informed by a triggers-to-action framework to establish the evidentiary base of harm to consumers, operationalize policy solutions to mitigate harm through legislation, and generate political will to support action through legislation introduced in the Massachusetts legislature to restrict sales of weight-loss and muscle-building dietary supplements. The paper concludes with lessons learned from this unique policy translation effort for the prevention of disordered weight and shape control behaviors and offers recommendations for next steps for the field to advance research and practice for universal, macro-environmentally targeted prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Intrinsic Foot Muscle Activation During Specific Exercises: A T2 Time Magnetic Resonance Imaging Study.

    PubMed

    Gooding, Thomas M; Feger, Mark A; Hart, Joseph M; Hertel, Jay

    2016-08-01

    The intrinsic foot muscles maintain the medial longitudinal arch and aid in force distribution and postural control during gait. Impaired intrinsic foot-muscle function has been linked to various foot conditions. Several rehabilitative exercises have been proposed to improve it; however, literature that identifies which individual muscles are activated during specific intrinsic foot-muscle exercises is lacking. To describe changes in activation of the intrinsic plantar foot muscles after 4 exercises as measured with T2 magnetic resonance imaging (MRI). Descriptive laboratory study. Research laboratory. Eight healthy National Collegiate Athletic Association Division I collegiate cross-country and track athletes (5 men and 3 women: age = 20 ± 0.93 years, height = 180.98 ± 10.84 cm, mass = 70.91 ± 7.82 kg). Participants underwent T2 MRI before and after each exercise. They completed 1 set of 40 repetitions of each exercise (short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension). Percentage increases in muscle activation of the abductor hallucis, flexor digitorum brevis, abductor digiti minimi, quadratus plantae, flexor digiti minimi, adductor hallucis oblique, flexor hallucis brevis, and interossei and lumbricals (analyzed together) after each exercise were assessed using T2 MRI. All muscles showed increased activation after all exercises. The mean percentage increase in activation ranged from 16.7% to 34.9% for the short-foot exercise, 17.3% to 35.2% for toes spread out, 13.1% to 18.1% for first-toe extension, and 8.9% to 22.5% for second- to fifth-toes extension. All increases in activation had associated 95% confidence intervals that did not cross zero. Each of the 4 exercises was associated with increased activation in all of the plantar intrinsic foot muscles evaluated. These results may have clinical implications for the prescription of specific exercises to target individual intrinsic foot muscles.

  15. Analysis of fatty infiltration and inflammation of the pelvic and thigh muscles in boys with Duchenne muscular dystrophy (DMD): grading of disease involvement on MR imaging and correlation with clinical assessments.

    PubMed

    Kim, Hee Kyung; Merrow, Arnold C; Shiraj, Sahar; Wong, Brenda L; Horn, Paul S; Laor, Tal

    2013-10-01

    Prior reports focus primarily on muscle fatty infiltration in Duchenne muscular dystrophy (DMD). However, the significance of muscle edema is uncertain. To evaluate the frequency and degree of muscle fat and edema, and correlate these with clinical function. Forty-two boys (ages 5-19 years) with DMD underwent pelvic MRI. Axial T1- and fat-suppressed T2-weighted images were evaluated to grade muscle fatty infiltration (0-4) and edema (0-3), respectively. Degree and frequency of disease involvement were compared to clinical evaluations. Gluteus maximus had the greatest mean fatty infiltration score, followed by adductor magnus and gluteus medius muscles, and had the most frequent and greatest degree of fatty infiltration. Gluteus maximus also had the greatest mean edema score, followed by vastus lateralis and gluteus medius muscles. These muscles had the most frequent edema, although the greatest degree of edema was seen in other muscles. There was correlation between cumulative scores of fatty infiltration and all clinical evaluations (P < 0.05). In DMD, the muscles with the most frequent fatty infiltration had the greatest degree of fatty infiltration and correlated with patient function. However, the muscles with the most frequent edema were different from those with the greatest degree of edema. Thus, edema may not predict patient functional status.

  16. Alterations in intrinsic mitochondrial function with aging are fiber type-specific and do not explain differential atrophy between muscles.

    PubMed

    Picard, Martin; Ritchie, Darmyn; Thomas, Melissa M; Wright, Kathryn J; Hepple, Russell T

    2011-12-01

    To determine whether mitochondrial dysfunction is causally related to muscle atrophy with aging, we examined respiratory capacity, H(2) O(2) emission, and function of the mitochondrial permeability transition pore (mPTP) in permeabilized myofibers prepared from four rat muscles that span a range of fiber type and degree of age-related atrophy. Muscle atrophy with aging was greatest in fast-twitch gastrocnemius (Gas) muscle (-38%), intermediate in both the fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus (Sol) muscles (-21%), and non-existent in adductor longus (AL) muscle (+47%). In contrast, indices of mitochondrial dysfunction did not correspond to this differential degree of atrophy. Specifically, despite higher protein expression for oxidative phosphorylation (oxphos) system in fast Gas and EDL, state III respiratory capacity per myofiber wet weight was unchanged with aging, whereas the slow Sol showed proportional decreases in oxphos protein, citrate synthase activity, and state III respiration. Free radical leak (H(2) O(2) emission per O(2) flux) under state III respiration was higher with aging in the fast Gas, whereas state II free radical leak was higher in the slow AL. Only the fast muscles had impaired mPTP function with aging, with lower mitochondrial calcium retention capacity in EDL and shorter time to mPTP opening in Gas and EDL. Collectively, our results underscore that the age-related changes in muscle mitochondrial function depend largely upon fiber type and are unrelated to the severity of muscle atrophy, suggesting that intrinsic changes in mitochondrial function are unlikely to be causally involved in aging muscle atrophy. © 2011 The Authors. Aging Cell © 2011 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

  17. Magnetic resonance imaging of live freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Michael, Holliman F.; Davis, Denise; Bogan, Arthur E.; Kwak, Thomas J.; Cope, W. Gregory; Levine, Jay F.

    2008-01-01

    We examined the soft tissues of live freshwater mussels, Eastern elliptio Elliptio complanata, via magnetic resonance imaging (MRI), acquiring data with a widely available human whole-body MRI system. Anatomical features depicted in the profile images included the foot, stomach, intestine, anterior and posterior adductor muscles, and pericardial cavity. Noteworthy observations on soft tissue morphology included a concentration of lipids at the most posterior aspect of the foot, the presence of hemolymph-filled fissures in the posterior adductor muscle, the presence of a relatively large hemolymph-filled sinus adjacent to the posterior adductor muscle (at the ventral-anterior aspect), and segmentation of the intestine (a diagnostic description not reported previously in Unionidae). Relatively little is known about the basic biology and ecological physiology of freshwater mussels. Traditional approaches for studying anatomy and tissue processes, and for measuring sub-lethal physiological stress, are destructive or invasive. Our study, the first to evaluate freshwater mussel soft tissues by MRI, clarifies the body plan of unionid mussels and demonstrates the efficacy of this technology for in vivoevaluation of the structure, function, and integrity of mussel soft tissues.

  18. Effect of the callipyge phenotype and cooking method on tenderness of several major lamb muscles.

    PubMed

    Shackelford, S D; Wheeler, T L; Koohmaraie, M

    1997-08-01

    We conducted three experiments to determine the effects of the callipyge phenotype on the tenderness of several major lamb muscles and to determine the effect of method of cookery on the tenderness of callipyge lamb at 7 d postmortem. In Exp. 1, chops from normal (n = 23) and callipyge (n = 16) carcasses were open-hearth-broiled. Warner-Bratzler shear force values of longissimus, gluteus medius, semimembranosus, biceps femoris, semitendinosus, adductor, and quadriceps femoris were 123, 44, 28, 26, 19, 16, and 13% greater, respectively, for callipyge (P < .05). In Exp. 2, muscles from normal (n = 18) and callipyge (n = 18) carcasses were oven-roasted. Shear force of triceps brachii was 11% greater for callipyge (P < .001); however, phenotype did not affect shear force of supraspinatus (P = .87) or psoas major (P = .64). In Exp. 3, a trained sensory panel evaluated leg roasts and open-hearth-broiled leg chops from normal (n = 60) and callipyge lamb carcasses (n = 60). Callipyge chops were less tender than normal chops (P < .05). Regardless of callipyge phenotype, muscles were more (P < .05) tender when roasted; however, the effect of method of cookery on tenderness scores was greater for callipyge muscles than for normal muscles. Callipyge roasts and normal roasts had similar tenderness (P = .58), and callipyge roasts were more tender than normal chops (P < .05). Regardless of cooking method, callipyge samples were less juicy than normal samples (P < .05). These data demonstrate that the callipyge phenotype will likely reduce consumer satisfaction due to reduced tenderness and juiciness; however, reduced tenderness in callipyge leg muscles could be prevented by ovenroasting.

  19. Cranial muscle development in the model organism ambystoma mexicanum: implications for tetrapod and vertebrate comparative and evolutionary morphology and notes on ontogeny and phylogeny.

    PubMed

    Ziermann, Janine M; Diogo, Rui

    2013-07-01

    There is still confusion about the homology of several cranial muscles in salamanders with those of other vertebrates. This is true, in part, because of the fact that many muscles present in early ontogeny of amphibians disappear during development and specifically during metamorphosis. Resolving this confusion is important for the understanding of the comparative and evolutionary morphology of vertebrates and tetrapods because amphibians are the phylogenetically most plesiomorphic tetrapods, concerning for example their myology, and include two often used model organisms, Xenopus laevis (anuran) and Ambystoma mexicanum (urodele). Here we provide the first detailed report of the cranial muscle development in axolotl from early ontogenetic stages to the adult stage. We describe different and complementary types of general muscle morphogenetic gradients in the head: from anterior to posterior, from lateral to medial, and from origin to insertion. Furthermore, even during the development of neotenic salamanders such as axolotls, various larval muscles become indistinct, contradicting the commonly accepted view that during ontogeny the tendency is mostly toward the differentiation of muscles. We provide an updated comparison between these muscles and the muscles of other vertebrates, a discussion of the homologies and evolution, and show that the order in which the muscles appear during axolotl ontogeny is in general similar to their appearance in phylogeny (e.g. differentiation of adductor mandibulae muscles from one anlage to four muscles), with only a few remarkable exceptions, as for example the dilatator laryngis that appears evolutionary later but in the development before the intermandibularis. Copyright © 2013 Wiley Periodicals, Inc.

  20. Effects of microgravity on muscle and cerebral cortex: a suggested interaction

    NASA Astrophysics Data System (ADS)

    D'Amelio, F.; Fox, R. A.; Wu, L. C.; Daunton, N. G.; Corcoran, M. L.

    The ``slow'' antigravity muscle adductor longus was studied in rats after 14 days of spaceflight (SF). The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light and electron microscopy revealed myofiber atrophy, segmental necrosis and regenerative myofibers. Regenerative myofibers were N-CAM immunoreactive (N-CAM-IR). The neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles, degenerative changes, vacant axonal spaces and changes suggestive of axonal sprouting. No alterations of muscle spindles was seen either by light or electron microscopy. These observations suggest that muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight. In a separate study, GABA immunoreactivity (GABA-IR) was evaluated at the level of the hindlimb representation of the rat somatosensory cortex after 14 days of hindlimb unloading by tail suspension (``simulated'' microgravity). A reduction in number of GABA-immunoreactive cells with respect to the control animals was observed in layer Va and Vb. GABA-IR terminals were also reduced in the same layers, particularly those terminals surrounding the soma and apical dendrites of pyramidal cells in layer Vb. On the basis of previous morphological and behavioral studies of the neuromuscular system after spaceflight and hindlimb suspension it is suggested that after limb unloading there are alterations of afferent signaling and feedback information from intramuscular receptors to the cerebral cortex due to modifications in the reflex organization of hindlimb muscle groups. We propose that the changes observed in GABA immunoreactivity of cells and terminals is an expression of changes in their modulatory activity to compensate for the alterations in the afferent information.

  1. Experimental pain in the groin may refer into the lower abdomen: Implications to clinical assessments.

    PubMed

    Drew, M K; Palsson, T S; Hirata, R P; Izumi, M; Lovell, G; Welvaert, M; Chiarelli, P; Osmotherly, P G; Graven-Nielsen, T

    2017-10-01

    To investigate the effects of experimental adductor pain on the pain referral pattern, mechanical sensitivity and muscle activity during common clinical tests. Repeated-measures design. In two separate sessions, 15 healthy males received a hypertonic (painful) and isotonic (control) saline injection to either the adductor longus (AL) tendon to produce experimental groin pain or into the rectus femoris (RF) tendon as a painful control. Pain intensity was recorded on a visual analogue scale (VAS) with pain distribution indicated on body maps. Pressure pain thresholds (PPT) were assessed bilaterally in the groin area. Electromyography (EMG) of relevant muscles was recorded during six provocation tests. PPT and EMG assessment were measured before, during and after experimental pain. Hypertonic saline induced higher VAS scores than isotonic saline (p<0.001), and a local pain distribution in 80% of participants. A proximal pain referral to the lower abdominal region in 33% (AL) and 7% (RF) of participants. Experimental pain (AL and RF) did not significantly alter PPT values or the EMG amplitude in groin or trunk muscles during provocation tests when forces were matched with baseline. This study demonstrates that AL tendon pain was distributed locally in the majority of participants but may refer to the lower abdomen. Experimental adductor pain did not significantly alter the mechanical sensitivity or muscle activity patterns. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. Laryngeal dystonia gravidarum: sudden onset of adductor spasmodic dysphonia in pregnancy.

    PubMed

    Ankola, Ashish; Sulica, Lucian; Murry, Thomas

    2013-12-01

    The purpose of this study was to identify the presence or absence of known factors related to onset of adductor spasmodic dysphonia (ADSD) in a population with sudden onset during or after pregnancy. Retrospective review. A review of 350 patient records identified five patients with sudden onset of ADSD related to pregnancy. An age-matched group with sudden onset of ADSD not related to pregnancy served as controls. All subjects completed a 20-question survey of risk factors relevant to ADSD. The average age of onset in both groups was 31 years. Three had onset of ADSD in the postpartum period, the other two during pregnancy. Significantly increased avocational voice use was found in the pregnant group compared to the control group. There was a significant difference in the two groups regarding cumulative risk factors traditionally associated with ADSD. Sudden onset of ADSD can occur in pregnancy in women with clinical profiles that differ from traditional ADSD patients. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Bite force estimation and the fiber architecture of felid masticatory muscles.

    PubMed

    Hartstone-Rose, Adam; Perry, Jonathan M G; Morrow, Caroline J

    2012-08-01

    Increasingly, analyses of craniodental dietary adaptations take into account mechanical properties of foods. However, masticatory muscle fiber architecture has been described for relatively few lineages, even though an understanding of the scaling of this anatomy can yield important information about adaptations for stretch and strength in the masticatory system. Data on the mandibular adductors of 28 specimens from nine species of felids representing nearly the entire body size range of the family allow us to evaluate the influence of body size and diet on the masticatory apparatus within this lineage. Masticatory muscle masses scale isometrically, tending toward positive allometry, with body mass and jaw length. This allometry becomes significant when the independent variable is a geometric mean of cranial variables. For all three body size proxies, the physiological cross-sectional area and predicted bite forces scale with significant positive allometry. Average fiber lengths (FL) tend toward negative allometry though with wide confidence intervals resulting from substantial scatter. We believe that these FL residuals are affected by dietary signals within the sample; though the mechanical properties of felid diets are relatively similar across species, the most durophagous species in our sample (the jaguar) appears to have relatively higher force production capabilities. The more notable dietary trend in our sample is the relationship between FL and relative prey size: felid species that predominantly consume relatively small prey have short masticatory muscle fibers, and species that regularly consume relatively large prey have relatively long fibers. This suggests an adaptive signal related to gape. Copyright © 2012 Wiley Periodicals, Inc.

  4. Comparison of lower limb muscle activation with ballet movements (releve and demi-plie) and general movements (heel rise and squat) in healthy adults.

    PubMed

    Kim, Min-Ju; Kim, Joong-Hwi

    2016-01-01

    [Purpose] The aim of this study was to demonstrate therapeutic grounds for rehabilitation exercise approach by comparing and analyzing muscular activities of Ballet movements: the releve movement (RM) and the demi-plie movement (DM). [Methods] Four types of movements such as RM vs. heel rise (HM) and DM vs. squat movement (SM) were randomized and applied in 30 healthy male and female individuals while measuring 10-s lower limb muscular activities (gluteus maximus [GMa], gluteus medius [GMe], rectus femoris [RF], adductor longus [AL], medial gastrocnemius [MG], and lateral gastrocnemius [LG]) by using surface electromyography (EMG). [Results] Significant differences were found in GMa, GMe, AL and MG activities for DM and in all of the six muscles for RM, in particular when the two groups were compared (RM vs HM and DM vs SM). [Conclusion] The RM and DM have a greater effect on lower limb muscular force activities compared to HM and SM and could be recommended as clinical therapeutic exercises for lower limb muscle enhancement.

  5. [Nutrition and biological value of food parts of a trade bivalve mollusk Anadara broughtoni].

    PubMed

    Tabakaeva, O V; Tabakaev, A V

    2015-01-01

    Currently, the human diet includes different new products of seafishing, including non-fish--bivalves and gastropods, holothurias, echinoderms, jellyfishes that demands careful studying of their chemical composition. The purpose of the study was to determine the nutritional and biological value of all soft parts of the burrowing bivalve MOLLUSK Anadara broughtoni from the Far East region. It was established thatfood parts of a bivalve were significantly flooded (water content--73.5-84.2%), with the minimum water content in the adductor and maximum in the mantle. Dry solids are presented by organic (89-93%) and mineral (7-11%) components. Organic components consist of protein (14.6-20.7%), lipids (1.8-2.3%), carbohydrates (2.1-2.6%). The analysis of amino-acid composition of proteins of food parts of the mollusk of Anadara broughtonishowed the presence of all essential amino acids with slight differences in their content depending on the localization of the protein. All edible parts have tryptophan as the limiting amino acid. Muscle proteins have maximum level of lysine, methionine, cysteine, phenylalanine and tyrosine; mantle proteins--leucine, isoleucine and threonine; adductor proteins--valine, phenylalanine, tyrosine, methionine and cysteine. Predominant nonessential amino acids forproteins of all food pieces are glycine, aspartic acid, glutamic acid, arginine. The coefficient of amino-acid score differences of adductor protein (31.7%) is less than the same of cloak by 3.7%. The indicator "biological value" is maximal for adductor (68.3%), but the differenceformuscle is only 0.83%. Mantle proteins are characterized by minimum biological value (64.6%). The coefficient of utility of amino acid composition of protein is maximalfor muscle (57.83%), and values for a cloak and an adductor differ slightly (55.81 and 55.96%). Taurine content in food parts of a mollusk Anadara broughtoni is rather high compared to with other bivalve mollusks of the Far East region

  6. The relationship of strength and muscle balance to shoulder pain and impingement syndrome in elite quadriplegic wheelchair rugby players.

    PubMed

    Miyahara, M; Sleivert, G G; Gerrard, D F

    1998-04-01

    Wheelchair athletes are susceptible to injuries related to overuse of the shoulder, in particular shoulder impingement syndrome. The present study examined the relationship of shoulder pain to demographic details, isokinetic strength and muscle balance in 8 elite quadriplegic rugby players. Demographic data were collected using personal interviews and each subject was clinically examined for signs of impingement syndrome by a physician. In addition each subject underwent bilateral isokinetic strength testing of the shoulder at 60 and 180 deg/s for abduction/adduction and internal/external rotation. A series of step-wise multiple discriminant analysis successfully predicted clinical symptoms from demographic, muscular strength and balance data. In particular, there was a significant deficit in adductor strength and this was related to shoulder pain and wasting of the scapular muscles. This strength deficit may be due to the high level of spinal lesions in the quadriplegic population. The level of spinal lesion may contribute to the aetiology of shoulder pathology in quadriplegia, and differentiate it from that observed in able-bodied athletes who exhibit weak abductors.

  7. The influence of changes in trunk and pelvic posture during single leg standing on hip and thigh muscle activation in a pain free population.

    PubMed

    Prior, Simon; Mitchell, Tim; Whiteley, Rod; O'Sullivan, Peter; Williams, Benjamin K; Racinais, Sebastien; Farooq, Abdulaziz

    2014-03-27

    Thigh muscle injuries commonly occur during single leg loading tasks and patterns of muscle activation are thought to contribute to these injuries. The influence trunk and pelvis posture has on hip and thigh muscle activation during single leg stance is unknown and was investigated in a pain free population to determine if changes in body posture result in consistent patterns of changes in muscle activation. Hip and thigh muscle activation patterns were compared in 22 asymptomatic, male subjects (20-45 years old) in paired functionally relevant single leg standing test postures: Anterior vs. Posterior Trunk Sway; Anterior vs. Posterior Pelvic Rotation; Left vs. Right Trunk Shift; and Pelvic Drop vs. Raise. Surface EMG was collected from eight hip and thigh muscles calculating Root Mean Square. EMG was normalized to an "upright standing" reference posture. Repeated measures ANOVA was performed along with associated F tests to determine if there were significant differences in muscle activation between paired test postures. In right leg stance, Anterior Trunk Sway (compared to Posterior Sway) increased activity in posterior sagittal plane muscles, with a concurrent deactivation of anterior sagittal plane muscles (p: 0.016 - <0.001). Lateral hip abductor muscles increased activation during Left Trunk Shift (compared to Right) (p :≤ 0.001). Lateral Pelvic Drop (compared to Raise) decreased activity in hip abductors and increased hamstring, adductor longus and vastus lateralis activity (p: 0.037 - <0.001). Changes in both trunk and pelvic posture during single leg stance generally resulted in large, predictable changes in hip and thigh muscle activation in asymptomatic young males. Changes in trunk position in the sagittal plane and pelvis position in the frontal plane had the greatest effect on muscle activation. Investigation of these activation patterns in clinical populations such as hip and thigh muscle injuries may provide important insights into injury

  8. Adductor canal block with local infiltrative analgesia compared with local infiltrate analgesia for pain control after total knee arthroplasty: A meta-analysis of randomized controlled trials.

    PubMed

    Xing, Qiujuan; Dai, Weiwei; Zhao, Dongfeng; Wu, Ji; Huang, Chunshui; Zhao, Yun

    2017-09-01

    This meta-analysis aimed to evaluate the efficiency and safety of the combined adductor canal block with peri-articular infiltration versus periarticular infiltration alone for pain control after total knee arthroplasty (TKA). PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched to identify articles comparing the combined adductor canal block with peri-articular infiltration and periarticular infiltration alone for pain control after TKA. Main outcomes were numeric rating scale (NRS) at postoperative day (POD) 0-2 and opioid consumption. Meta-analysis was performed using Stata 11.0 software. Four randomized controlled trial (RCTs) including 297 patients met the inclusion criteria. The present meta-analysis indicated that there were significant differences between the groups regarding NRS score at POD 0 (weighted mean difference [WMD] = -0.849, 95% confidence interval [CI]: -1.345 to -0.353, P = .001), POD 1 (WMD = -0.960, 95% CI: -1.474 to -0.446, P = .000), and POD 2 (WMD = -0.672, 95% CI: -1.163 to -0.181, P = .007) after TKA. Significant differences were found in terms of opioid consumption at POD 0 (WMD = -3.761, 95% CI: -6.192 to -1.329, P = .002), POD 1 (WMD = -4.795, 95% CI: -8.181 to -1.409, P = .006), and POD 2 (WMD = -2.867, 95% CI: -4.907 to -0.827, P = .006). Combined adductor canal block with peri-articular infiltration could significantly reduce NRS scores and opioid consumption in comparison with periarticular infiltration alone following TKA. Additionally, there is a lower incidence of nausea and vomiting in the combined groups.

  9. Intraoperative Adductor Canal Block for Augmentation of Periarticular Injection in Total Knee Arthroplasty: A Cadaveric Study.

    PubMed

    Pepper, Andrew M; North, Trevor W; Sunderland, Adam M; Davis, Jason J

    2016-09-01

    Function is often sacrificed for pain control after total knee arthroplasty. Motor-sparing blocks, including adductor canal block (ACB) and periarticular injection (PAI), have gained interest to address this compromise. Our study evaluates the anatomic feasibility, accuracy, and safety of intraoperative ACB as an adjunct to PAI by analyzing 3 different injection orientations and needle configurations. Eleven cadaveric knees underwent a standard medial parapatellar arthrotomy. Blunt dissection through the suprapatellar recess was performed. Using a 10-mL syringe, various colors of dyed liquid gelatin were injected toward the proximal and distal adductor canal (AC) using 3 needle configurations. Medial dissection of the knee for each specimen was performed. The position of each needle and location of injected dye was identified and described relative to the AC. Accuracy of each injection orientation and/or needle configuration was different: 86% for a blunt needle in the distal AC, 57% for blunt needle in the proximal AC, and 14% for a spinal needle in the proximal AC. Puncture of the femoral artery was observed with the spinal needle 43% of the time and had the closest average proximity to the femoral artery with a distance of 5.9 mm. There were no vascular punctures using blunt needles, and the average distance from the femoral artery with proximal and distal orientation was 10.2 mm and 15.4 mm, respectively. Intraoperative ACB augmentation of PAI appears to be anatomically feasible and safe. There was decreased accuracy and increased risk of vascular puncture using a 3.5-inch spinal needle. A blunt 1.5-inch needle directed toward the distal AC had the highest accuracy while minimizing vascular injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. [Pubalgia in sportsmen].

    PubMed

    Zeitoun, F; Frot, B; Sterin, P; Tubiana, J M

    1995-01-01

    Pubalgia is a painful syndrome of the groin which particularly affects young athletes. Although soccer players are the athletes most often affected, they are not alone. Also included in this group are fencers, tennis players and rugbymen. This ailment is associated with varying degrees of lesions of the muscles of the lower frontal abdomen, pubic symphysis and adductor muscles. The clinical diagnosis is confirmed by standard X-rays which can show radiological anomalies of the pubic symphysis in cases of microtraumatic pubic osteo-arthropathy or insertion tendinitis. Scintigraphic anomalies occur earlier than radiological anomalies and return to normal before them; thus allowing confirmation of healing even when the radiographs are still abnormal. Sonogram and MRI can be advantageous in the detection of a lesion of the abdominal muscles or adductor muscles. MRI can also detect a lesion of the pubic symphysis. The principal differential diagnosis is pubic osteitis. Treatment is medical and combines rest, analgesics and anti-inflammatories. Surgery, namely Nesovic's operation, is reserved for those forms resistant to medical treatment, and must be bilateral.

  11. Neuromuscular control of fundamental frequency and glottal posture at phonation onset

    PubMed Central

    Chhetri, Dinesh K.; Neubauer, Juergen; Berry, David A.

    2012-01-01

    The laryngeal neuromuscular mechanisms for modulating glottal posture and fundamental frequency are of interest in understanding normal laryngeal physiology and treating vocal pathology. The intrinsic laryngeal muscles in an in vivo canine model were electrically activated in a graded fashion to investigate their effects on onset frequency, phonation onset pressure, vocal fold strain, and glottal distance at the vocal processes. Muscle activation plots for these laryngeal parameters were evaluated for the interaction of following pairs of muscle activation conditions: (1) cricothyroid (CT) versus all laryngeal adductors (TA/LCA/IA), (2) CT versus LCA/IA, (3) CT versus thyroarytenoid (TA) and, (4) TA versus LCA/IA (LCA: lateral cricoarytenoid muscle, IA: interarytenoid). Increases in onset frequency and strain were primarily affected by CT activation. Onset pressure correlated with activation of all adductors in activation condition 1, but primarily with CT activation in conditions 2 and 3. TA and CT were antagonistic for strain. LCA/IA activation primarily closed the cartilaginous glottis while TA activation closed the mid-membranous glottis. PMID:22352513

  12. Comparison of lower limb muscle activation with ballet movements (releve and demi-plie) and general movements (heel rise and squat) in healthy adults

    PubMed Central

    Kim, Min-Ju; Kim, Joong-Hwi

    2016-01-01

    [Purpose] The aim of this study was to demonstrate therapeutic grounds for rehabilitation exercise approach by comparing and analyzing muscular activities of Ballet movements: the releve movement (RM) and the demi-plie movement (DM). [Methods] Four types of movements such as RM vs. heel rise (HM) and DM vs. squat movement (SM) were randomized and applied in 30 healthy male and female individuals while measuring 10-s lower limb muscular activities (gluteus maximus [GMa], gluteus medius [GMe], rectus femoris [RF], adductor longus [AL], medial gastrocnemius [MG], and lateral gastrocnemius [LG]) by using surface electromyography (EMG). [Results] Significant differences were found in GMa, GMe, AL and MG activities for DM and in all of the six muscles for RM, in particular when the two groups were compared (RM vs HM and DM vs SM). [Conclusion] The RM and DM have a greater effect on lower limb muscular force activities compared to HM and SM and could be recommended as clinical therapeutic exercises for lower limb muscle enhancement. PMID:26957762

  13. Mapping intramuscular tenderness variation in four major muscles of the beef round.

    PubMed

    Reuter, B J; Wulf, D M; Maddock, R J

    2002-10-01

    The objective of this study was to quantify intramuscular tenderness variation within four muscles from the beef round: biceps femoris (BF), semitendinosus (ST), semimembranosus (SM), and adductor (AD). At 48 h postmortem, the BF, ST, SM, and AD were dissected from either the left or right side of ten carcasses, vacuum packaged, and aged for an additional 8 d. Each muscle was then frozen and cut into 2.54-cm-thick steaks perpendicular to the long axis of the muscle. Steaks were broiled on electric broilers to an internal temperature of 71 degrees C. Location-specific cores were obtained from each cooked steak, and Warner-Bratzler shear force was evaluated. Definable intramuscular shear force variation (SD = 0.56 kg) was almost twice as large as between-animal shear force variation (SD = 0.29 kg) and 2.8 times as large as between-muscle variation (SD = 0.20 kg). The ranking of muscles from greatest to least definable intramuscular shear force variation was BF, SM, ST, and AD (SD = 1.09, 0.72, 0.29, and 0.15 kg, respectively). The BF had its lowest shear force values at the origin (sirloin end), intermediate shear force values at the insertion, and its highest shear force values in a middle region 7 to 10 cm posterior to the sirloin-round break point (P < 0.05). The BF had lower shear force values toward the ST side than toward the vastus lateralis side (P < 0.05). The ST had its lowest shear force values in a 10-cm region in the middle, and its highest shear force values toward each end (P < 0.05). The SM had its lowest shear force values in the first 10-cm from the ischial end (origin), and its highest shear force values in a 13-cm region at the insertion end (P < 0.05). Generally, shear force was lower toward the superficial (medial) side than toward the deep side of the SM (P < 0.05). There were no intramuscular differences in shear force values within the AD (P > 0.05). These data indicate that definable intramuscular tenderness variation is substantial and

  14. Congruence between muscle activity and kinematics in a convergently derived prey-processing behavior.

    PubMed

    Konow, Nicolai; Camp, Ariel L; Sanford, Christopher P J

    2008-08-01

    Quantification of anatomical and physiological characteristics of the function of a musculoskeletal system may yield a detailed understanding of how the organizational levels of morphology, biomechanics, kinematics, and muscle activity patterns (MAPs) influence behavioral diversity. Using separate analyses of these organizational levels in representative study taxa, we sought patterns of congruence in how organizational levels drive behavioral modulation in a novel raking prey-processing behavior found in teleosts belonging to two evolutionarily distinct lineages. Biomechanically divergent prey (elusive, robust goldfish and sedentary, malleable earthworms) were fed to knifefish, Chitala ornata (Osteoglossomorpha) and brook trout, Salvelinus fontinalis (Salmoniformes). Electromyography recorded MAPs from the hyoid protractor, jaw adductor, sternohyoideus, epaxialis, and hypaxialis musculature, while sonomicrometry sampled deep basihyal kinesis and contractile length dynamics in the basihyal protractor and retractor muscles. Syntheses of our results with recent analyses of cranial morphology and raking kinematics showed that raking in Salvelinus relies on an elongated cranial out lever, extensive cranial elevation and a curved cleithrobranchial ligament (CBL), and that both raking MAPs and kinematics remain entirely unmodulated-a highly unusual trait, particularly among feeding generalists. Chitala had a shorter CBL and a raking power stroke involving increased retraction of the elongated pectoral girdle during raking on goldfish. The raking MAP was also modulated in Chitala, involving an extensive overlap between muscle activity of the preparatory and power stroke phases, driven by shifts in hypaxial timing and recruitment of the hyoid protractor muscle. Sonomicrometry revealed that the protractor hyoideus muscle stored energy from retraction of the pectoral girdle for ca. 5-20 ms after onset of the power stroke and then hyper-extended. This mechanism of elastic

  15. Inferring speaker attributes in adductor spasmodic dysphonia: ratings from unfamiliar listeners.

    PubMed

    Isetti, Derek; Xuereb, Linnea; Eadie, Tanya L

    2014-05-01

    To determine whether unfamiliar listeners' perceptions of speakers with adductor spasmodic dysphonia (ADSD) differ from control speakers on the parameters of relative age, confidence, tearfulness, and vocal effort and are related to speaker-rated vocal effort or voice-specific quality of life. Twenty speakers with ADSD (including 6 speakers with ADSD plus tremor) and 20 age- and sex-matched controls provided speech recordings, completed a voice-specific quality-of-life instrument (Voice Handicap Index; Jacobson et al., 1997), and rated their own vocal effort. Twenty listeners evaluated speech samples for relative age, confidence, tearfulness, and vocal effort using rating scales. Listeners judged speakers with ADSD as sounding significantly older, less confident, more tearful, and more effortful than control speakers (p < .01). Increased vocal effort was strongly associated with decreased speaker confidence (rs = .88-.89) and sounding more tearful (rs = .83-.85). Self-rated speaker effort was moderately related (rs = .45-.52) to listener impressions. Listeners' perceptions of confidence and tearfulness were also moderately associated with higher Voice Handicap Index scores (rs = .65-.70). Unfamiliar listeners judge speakers with ADSD more negatively than control speakers, with judgments extending beyond typical clinical measures. The results have implications for counseling and understanding the psychosocial effects of ADSD.

  16. Everyday listeners' impressions of speech produced by individuals with adductor spasmodic dysphonia.

    PubMed

    Nagle, Kathleen F; Eadie, Tanya L; Yorkston, Kathryn M

    2015-01-01

    Individuals with adductor spasmodic dysphonia (ADSD) have reported that unfamiliar communication partners appear to judge them as sneaky, nervous or not intelligent, apparently based on the quality of their speech; however, there is minimal research into the actual everyday perspective of listening to ADSD speech. The purpose of this study was to investigate the impressions of listeners hearing ADSD speech for the first time using a mixed-methods design. Everyday listeners were interviewed following sessions in which they made ratings of ADSD speech. A semi-structured interview approach was used and data were analyzed using thematic content analysis. Three major themes emerged: (1) everyday listeners make judgments about speakers with ADSD; (2) ADSD speech does not sound normal to everyday listeners; and (3) rating overall severity is difficult for everyday listeners. Participants described ADSD speech similarly to existing literature; however, some listeners inaccurately extrapolated speaker attributes based solely on speech samples. Listeners may draw erroneous conclusions about individuals with ADSD and these biases may affect the communicative success of these individuals. Results have implications for counseling individuals with ADSD, as well as the need for education and awareness about ADSD. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Rehabilitation and Return to Sport Following Surgical Repair of the Rectus Abdominis and Adductor Longus in a Professional Basketball Player: A Case Report.

    PubMed

    Short, Steven M; Anloague, Philip A; Strack, Donald S

    2016-08-01

    Study Design Case report. Background Acute traumatic avulsion of the rectus abdominis and adductor longus is rare. Chronic groin injuries, often falling under the athletic pubalgia spectrum, have been reported to be more common. There is limited evidence detailing the comprehensive rehabilitation and return to sport of an athlete following surgical or conservative treatment of avulsion injuries of the pubis or other sports-related groin pathologies. Case Description A 29-year-old National Basketball Association player sustained a contact injury during a professional basketball game. This case report describes a unique clinical situation specific to professional sport, in which a surgical repair of an avulsed rectus abdominis and adductor longus was combined with a multimodal impairment- and outcomes-based rehabilitation program. Outcomes The patient returned to in-season competition at 5 weeks postoperation. Objective measures were tracked throughout rehabilitation and compared to baseline assessments. Measures such as the Copenhagen Hip and Groin Outcome Score and numeric pain-rating scale revealed progress beyond the minimal important difference. Discussion This case report details the clinical reasoning and evidence-informed interventions involved in the return to elite sport. Detailed programming and objective assessment may assist in achieving desired outcomes ahead of previously established timelines. Level of Evidence Therapy, level 4. J Orthop Sports Phys Ther 2016;46(8):697-706. Epub 3 Jul 2016. doi:10.2519/jospt.2016.6352.

  18. Recovery of laryngeal nerve function with sugammadex after rocuronium-induced profound neuromuscular block.

    PubMed

    Pavoni, Vittorio; Gianesello, Lara; Martinelli, Cristiana; Horton, Andrew; Nella, Alessandra; Gori, Gabriele; Simonelli, Martina; De Scisciolo, Giuseppe

    2016-09-01

    The aim of this study was to evaluate the efficacy of sugammadex in reversing profound rocuronium-induced neuromuscular block at the laryngeal adductor muscles using motor-evoked potentials (mMEPs). A prospective observational study. University surgical center. Twenty patients with American Society of Anesthesiologists physical class I-II status who underwent propofol-remifentanil anesthesia for the surgery of the thyroid gland. Patients were enrolled for reversal of profound neuromuscular block (sugammadex 16 mg/kg, 3 minutes after rocuronium 1.2 mg/kg). To prevent laryngeal nerve injury during the surgical procedures, all patients underwent neurophysiologic monitoring using mMEPs from vocal muscles. At the same time, the registration of TOF-Watch acceleromyograph at the adductor pollicis muscle response to ulnar nerve stimulation was performed; recovery was defined as a train-of-four (TOF) ratio ≥0.9. After injection of 16 mg/kg of sugammadex, the mean time to recovery of the basal mMEPs response at the laryngeal adductor muscles was 70 ± 18.2 seconds. The mean time to recovery of the TOF ratio to 0.9 was 118 ± 80 seconds. In the postoperative period, 12 patients received follow-up evaluation of the vocal cords and no lesions caused by the surface laryngeal electrode during electrophysiological monitoring were noted. Recovery from profound rocuronium-induced block on the larynx is fast and complete with sugammadex. In urgent scenarios, "early" extubation can be performed, even with a TOF ratio ≤0.9. However, all procedures to prevent postoperative residual curarization should still be immediately undertaken. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Hip and ankle range of motion and hip muscle strength in young female ballet dancersand controls

    PubMed Central

    Bennell, K.; Khan, K. M.; Matthews, B.; De Gruyter, M.; Cook, E.; Holzer, K.; Wark, J. D.

    1999-01-01

    OBJECTIVES: To compare the hip and ankle range of motion and hip muscle strength in 8-11 year old novice female ballet dancers and controls. METHODS: Subjects were 77 dancers and 49 controls (mean (SD) age 9.6 (0.8) and 9.6 (0.7) years respectively). Supine right active hip external rotation (ER) and internal rotation (IR) were measured using an inclinometer. A turnout protractor was used to assess standing active turnout range. The measure of ER achieved from below the hip during turnout (non-hip ER) was calculated by subtracting hip ER range from turnout range, and hip ER:IR was derived by dividing ER range by IR range. Range of right weight bearing ankle dorsiflexion was measured in a standing lunge using two methods: the distance from the foot to the wall (in centimetres) and the angle of the shank to the vertical via an inclinometer (in degrees). Right calf muscle range was measured in weight bearing using an inclinometer. A manual muscle tester was used to assess right isometric hip flexor, internal rotator, external rotator, abductor, and adductor strength. RESULTS: Dancers had less ER (p<0.05) and IR (p<0.01) range than controls but greater ER:IR (p<0.01). Although there was no difference in turnout between groups, the dancers had greater non-hip ER. Dancers had greater range of ankle dorsiflexion than controls, measured in both centimetres (p<0.01) and degrees (p<0.05), but similar calf muscle range. After controlling for body weight, controls had stronger hip muscles than dancers except for hip abductor strength which was similar. Regression analyses disclosed a moderate relation between turnout and hip ER (r = 0.40). There were no significant correlations between range of motion and training years and weekly training hours. CONCLUSIONS: Longitudinal follow up will assist in determining whether or not hip and ankle range in young dancers is genetically fixed and unable to be improved with further balletic training. 


 PMID:10522638

  20. Bone mineral density, muscle strength, and recreational exercise in men

    NASA Technical Reports Server (NTRS)

    Snow-Harter, C.; Whalen, R.; Myburgh, K.; Arnaud, S.; Marcus, R.

    1992-01-01

    Muscle strength has been shown to predict bone mineral density (BMD) in women. We examined this relationship in 50 healthy men who ranged in age from 28 to 51 years (average 38.3 years). BMD of the lumbar spine, proximal femur, whole body, and tibia were measured by dual-energy x-ray absorptiometry (Hologic QDR 1000W). Dynamic strength using one repetition maximum was assessed for the biceps, quadriceps, and back extensors and for the hip abductors, adductors, and flexors. Isometric grip strength was measured by dynamometry. Daily walking mileage was assessed by 9 week stepmeter records and kinematic analysis of video filming. Subjects were designated as exercisers and nonexercisers. Exercisers participated in recreational exercise at least two times each week. The results demonstrated that BMD at all sites correlated with back and biceps strength (p < 0.01 to p = 0.0001). Body weight correlated with tibia and whole-body BMD (p < 0.001); age negatively correlated with Ward's triangle BMD (p < 0.01). In stepwise multiple regressions, back strength was the only independent predictor of spine and femoral neck density (R2 = 0.27). Further, back strength was the most robust predictor of BMD at the trochanter, Ward's triangle, whole body, and tibia, although biceps strength, age, body weight, and leg strength contributed significantly to BMD at these skeletal sites, accounting for 35-52% of the variance in BMD. Exercisers and nonexercisers were similar for walking (3.97 versus 3.94 miles/day), age (37.8 versus 38.5) years, and weight (80.0 versus 77.7 kg). However, BMD and muscle strength were significantly greater in exercises than in nonexercisers.(ABSTRACT TRUNCATED AT 250 WORDS).

  1. The reproductive cycle, condition index, and glycogen reserves of the cockles Cerastoderma glaucum from the Gulf of Gabès (Tunisia).

    PubMed

    Karray, Sahar; Smaoui-Damak, Wafa; Rebai, Tarek; Hamza-Chaffai, Amel

    2015-11-01

    The gametogenic cycle of the Cerastoderma glaucum was analyzed using both qualitative and semi-quantitative methods. The condition index and glycogen concentrations were determined in order to provide information on energy storage. The cockles were collected monthly from a Bayyadha site located 15 km south of Sfax City (Gulf of Gabès) between January 2007 and January 2008. From histological point of view, we applied two approaches: (i) the qualitative method describing the various stages of gamete development for males and females during a cycle of 13 months, and (ii) the semi-quantitative method concerning the estimation of different tissue surfaces. The results showed that there is evidence of three periods of reproduction in this population. A comparison between the surfaces occupied by the three organs showed that the foot and the gonad surfaces are higher than the surface of the adductor muscle. This could suggest that these two organs are more involved in the process of glycogen reserve storage. The results of the glycogen concentrations in the different tissues (gonad, adductor muscle, and "remainders") show that during the second and third periods of reproduction, glycogen was stored in the adductor muscle and in the remainder during sexual rest, and in the gonad during the gametogenesis phases in order to supply the reproductive effort. On the contrary, in the first period of reproduction, the low concentrations of glycogen recorded in the gonad coincided with its high degree of development. This fact could be related to environmental conditions (low temperature and food) recorded during this period.

  2. Durophagy in sharks: feeding mechanics of the hammerhead Sphyrna tiburo.

    PubMed

    Wilga, C D; Motta, P J

    2000-09-01

    This study investigates the motor pattern and head movements during feeding of a durophagus shark, the bonnethead Sphyrna tiburo, using electromyography and simultaneous high-speed video. Sphyrna tiburo feeds almost exclusively on hard-shelled crabs, with shrimp and fish taken occasionally. It captures crabs by ram feeding, then processes or reduces the prey by crushing it between molariform teeth, finally transporting the prey by suction for swallowing. The prey-crushing mechanism is distinct from that of ram or bite capture and suction transport. This crushing mechanism is accomplished by altering the duration of jaw adductor muscle activity and modifying jaw kinematics by the addition of a second jaw-closing phase. In crushing events, motor activity of the jaw adductor muscles continues (biting of the prey occurs as the jaws close and continues after the jaws have closed) throughout a second jaw-closing phase, unlike capture and transport events during which motor activity (biting) ceases at jaw closure. Sphyrna tiburo is able to take advantage of a resource (hard prey) that is not readily available to most sharks by utilizing a suite of durophagous characteristics: molariform teeth, a modified jaw protrusor muscle, altered jaw adductor activity and modified jaw kinematics. Sphyrna tiburo is a specialist feeder on crab prey as demonstrated by the lack of differences in kinematic or motor patterns when offered prey of differing hardness and its apparent lack of ability to modulate its behavior when feeding on other prey. Functional patterns are altered and coupled with modifications in dental and jaw morphology to produce diverse crushing behaviors in elasmobranchs.

  3. Examination of body burden and taint for Iceland scallop (Chlamys islandica) and American plaice (Hippoglossoides platessoides) near the Terra Nova offshore oil development over ten years of drilling on the Grand Banks of Newfoundland, Canada

    NASA Astrophysics Data System (ADS)

    DeBlois, Elisabeth M.; Kiceniuk, Joe W.; Paine, Michael D.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Gregory Janes, G.

    2014-12-01

    This paper presents results of analyses of body burdens of metals and hydrocarbons, and taste tests for taint, in Iceland scallop and American plaice performed as part of the Environmental Effects Monitoring (EEM) program for the Terra Nova offshore oil development (Grand Banks of Newfoundland, Canada). Scallop and plaice were collected in a Study Area located within approximately 1 km of drill centres at Terra Nova and in a Reference Area located approximately 20 km from the development. Samples were collected in 1997 to establish a baseline, and from 2000 to 2010, during drilling periods. Scallop adductor muscle tissue was contaminated with >C10-C21 aliphatic hydrocarbons resembling the drilling fluid in the synthetic drilling mud (SBM) used at Terra Nova in 2000, 2002 and 2004, but contamination of adductor muscle was not noted in 2006, 2008 and 2010. The maximum concentration in muscle was 28 mg/kg wet weight, noted in 2002. Scallop viscera was contaminated with hydrocarbons resembling drilling fluid in SBMs near drill centres in all EEM years except 2010. Viscera contamination with >C10-C21 hydrocarbons gradually decreased from a maximum of 150 mg/kg in 2000, to a maximum of 27 mg/kg in 2008; all values were below the laboratory reporting detection limit of 15 mg/kg in 2010. Therefore, evidence from both muscle and viscera indicates a decrease in tissue hydrocarbon contamination in recent years. Barium, another major constituent in drilling muds, has not been noted in scallop adductor muscles at concentrations above the reporting detection limit, but barium was detected in viscera in baseline and EEM years. The maximum concentration of barium in viscera during baseline sampling was 8 mg/kg. The maximum concentration in EEM years (29 mg/kg) was noted in 2000. The maximum concentration in 2010 was 25 mg/kg. The concentration of metals other than barium in scallop tissues was similar between the Terra Nova Study Area and the Reference Area. Hydrocarbons

  4. The Effect of Rapacuronium or Succinylcholine on the Duration of Action of Rocuronium

    DTIC Science & Technology

    2001-10-01

    of the pre-determined rocuronium dose, supramaximal TOF sequence was evoked every 12 seconds to the anterior branch of the recurrent laryngeal nerve ...Paragraph™ Nerve Stimulator was used to observe the neuromuscular response (return of the second twitch) during the first maintenance dose of...of the train-of-four (TOF) twitch response is 62 seconds at the laryngeal muscles and 96 seconds at the adductor pollicis muscle. Similar to

  5. The 6-minute walk test, motor function measure and quantitative thigh muscle MRI in Becker muscular dystrophy: A cross-sectional study.

    PubMed

    Fischer, Dirk; Hafner, Patricia; Rubino, Daniela; Schmid, Maurice; Neuhaus, Cornelia; Jung, Hans; Bieri, Oliver; Haas, Tanja; Gloor, Monika; Fischmann, Arne; Bonati, Ulrike

    2016-07-01

    Becker muscular dystrophy (BMD) has an incidence of 1 in 16 000 male births. This cross-sectional study investigated the relation between validated functional scores and quantitative MRI (qMRI) of thigh muscles in 20 ambulatory BMD patients, aged 18.3-60 years (mean 31.2; SD 11.1). Clinical assessments included the motor function measure (MFM) and its subscales, as well as timed function tests such as the 6-minute walk test (6MWT) and the timed 10-m run/walk test. Quantitative MRI of the thigh muscles included the mean fat fraction (MFF) using a 2-point Dixon (2-PD) technique, and transverse relaxation time (T2) measurements. The mean MFM value was 80.4%, SD 9.44 and the D1 subscore 54.5%, SD 19.9. The median 6MWT was 195m, IQR 160-330.2. The median 10-m run/walk test was 7.4 seconds, IQR 6.1-9.3. The mean fat fraction of the thigh muscles was 55.6%, SD 17.4%, mean T2 relaxation times of all muscles: 69.9 ms, SD 14.4. The flexors had the highest MFF and T2 relaxation times, followed by the extensors and the adductors. MFF and global T2 relaxation times were highly negatively correlated with the MFM total, D1-subscore and 6MWT, and positively correlated with the 10 m run/walk test time (p < 0.01). Age was not correlated with MFF, global T2 relaxation time or clinical assessments. Both MFF and T2 measures in the thigh muscle were well correlated with clinical function in BMD and may serve as a surrogate outcome measure in clinical trials. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Depuration and anatomical distribution of the amnesic shellfish poisoning (ASP) toxin domoic acid in the king scallop Pecten maximus.

    PubMed

    Blanco, J; Acosta, C P; Bermúdez de la Puente, M; Salgado, C

    2002-10-02

    The depuration kinetics of the domoic acid of four body fractions (digestive gland, adductor muscle, gonad+kidney and gills+mantle) of the scallop Pecten maximus was studied over 295 days. The scallops, which had acquired the toxins during a Pseudo-nitzschia australis episode that took place the week before the beginning of the experiment, were maintained in tanks with running seawater. All the body fractions, except the adductor muscle, decreased their domoic acid burden throughout the experiment. The amount of toxin in the muscle dropped sharply at the start of the experiment but increased again at the end, to levels that were higher than the initial ones. Several dynamic models of depuration kinetics, which included the depuration of each fraction (excluding the adductor muscle) and the transfers between them, were constructed, implemented and fitted to the data to obtain their parameters. The estimated depuration rates were very low, both considering and not considering the transfer of toxin between organs or the effect of weight loss. There were strong differences in the domoic acid burden of the body fractions studied but not between their depuration rates. No net transfer from the digestive gland, the tissue with highest domoic acid concentration, to the other fractions was found, as the inclusion of these processes in the models produced only a marginally better fit to the data. The depuration of domoic acid was slightly, but significantly, affected by biomass. Weight loss induced domoic acid loss, suggesting that part of the depuration may be produced by the direct loss of bivalve cells. The concentration or dilution effect, due to decreases or increases in biomass, documented for other species and toxins, has little importance in Pecten maximus.

  7. 77 FR 54875 - Codex Alimentarius Commission: Meeting of the Codex Committee on Fish and Fishery Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... final product requirements) Proposed Food Additive Provisions in Standards for Fish and Fishery Products... (held at Step 7) Section 4 Food Additives Draft Standard for Quick Frozen Scallop Adductor Muscle Meat... DEPARTMENT OF AGRICULTURE Food Safety and Inspection Service [Docket No. FSIS-2012-0035] Codex...

  8. Botulinum Toxin-A Dosing Trends for Adductor Spasmodic Dysphonia at a Single Institution Over 10 Years.

    PubMed

    Bradley, Joseph P; Barrow, Emily M; Hapner, Edie R; Klein, Adam M; Johns, Michael M

    2017-05-01

    This study aimed to identify the changes in dosing of botulinum toxin-A for adductor spasmodic dysphonia (ADSD) over a prolonged period. This is a retrospective chart review. One hundred thirteen subjects treated for ADSD from 2003 to 2013 were identified from a clinical database. Subject age, gender, and total injection dose amount were all recorded for all subjects who had at least 10 injections. Fifty-four subjects met criteria for inclusion. There were no age or gender differences in the starting dose for subjects. Dosing decreased significantly compared with the second dose (5.05 ± 1.623 Units), by the sixth dose (4.26 ± 1.698 Units), and continued through the 10th dose (4.08 ± 2.019 Units) (P < 0.005 for all). Botulinum toxin-A dosing for ADSD decreases consistently over subsequent injections after the initial two dose titrations. Copyright © 2017. Published by Elsevier Inc.

  9. Muscle Volume Increases Following 16 Weeks of Resistive Exercise Training with the Advanced Resistive Exercise Device (ARED) and Free Weights

    NASA Technical Reports Server (NTRS)

    Nash, R. E.; Loehr, J. A.; Lee, S. M. C.; English, K. L.; Evans, H.; Smith, S. A.; Hagan, R. D.

    2009-01-01

    Space flight-induced muscle atrophy, particularly in the postural and locomotorymuscles, may impair task performance during long-duration space missions and planetary exploration. High intensity free weight (FW) resistive exercise training has been shown to prevent atrophy during bed rest, a space flight analog. NASA developed the Advanced Resistive Exercise Device (ARED) to simulate the characteristics of FW exercise (i.e. constant mass, inertial force) and to be used as a countermeasure during International Space Station (ISS) missions. PURPOSE: To compare the efficacy of ARED and FW training to induce hypertrophy in specific muscle groups in ambulatory subjects prior to deploying ARED on the ISS. METHODS: Twenty untrained subjects were assigned to either the ARED (8 males, 3 females) or FW (6 males, 3 females) group and participated in a periodizedtraining protocol consisting of squat (SQ), heel raise (HR), and deadlift(DL) exercises 3 d wk-1 for 16 wks. SQ, HR, and DL muscle strength (1RM) was measured before, after 8 wks, and after 16 wks of training to prescribe exercise and measure strength changes. Muscle volume of the vastigroup (V), hamstring group (H), hip adductor group (ADD), medial gastrocnemius(MG), lateral gastrocnemius(LG), and deep posterior muscles including soleus(DP) was measured using MRI pre-and post-training. Consecutive cross-sectional images (8 mm slices with a 2 mm gap) were analyzed and summed. Anatomical references insured that the same muscle sections were analyzed pre-and post-training. Two-way repeated measures ANOVAs (p<0.05) were used to test for differences in muscle strength and volume between training devices. RESULTS: SQ, HR, and DL 1RM increased in both FW (SQ: 49+/-6%, HR: 12+/-2%, DL: 23+/-4%) and ARED (SQ: 31+/-4%, HR: 18+/-2%, DL: 23+/-3%) groups. Both groups increased muscle volume in the V (FW: 13+/-2%, ARED: 10+/-2%), H (FW: 3+/-1%, ARED: 3+/-1 %), ADD (FW: 15=/-2%, ARED: 10+/-1%), LG (FW: 7+/-2%, ARED: 4+/-1%), MG (FW

  10. Muscle Adaptations Following Short-Duration Bed Rest with Integrated Resistance, Interval, and Aerobic Exercise

    NASA Technical Reports Server (NTRS)

    Hackney, Kyle J.; Scott, Jessica M.; Buxton, Roxanne; Redd-Goetchius, Elizabeth; Crowell, J. Brent; Everett, Meghan E.; Wickwire, Jason; Ryder, Jeffrey W.; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

    2011-01-01

    Unloading of the musculoskeletal system during space flight results in deconditioning that may impair mission-related task performance in astronauts. Exercise countermeasures have been frequently tested during bed rest (BR) and limb suspension; however, high-intensity, short-duration exercise prescriptions have not been fully explored. PURPOSE: To determine if a high intensity resistance, interval, and aerobic exercise program could protect against muscle atrophy and dysfunction when performed during short duration BR. METHODS: Nine subjects (1 female, 8 male) performed a combination of supine exercises during 2 weeks of horizontal BR. Resistance exercise (3 d / wk) consisted of squat, leg press, hamstring curl, and heel raise exercises (3 sets, 12 repetitions). Aerobic (6 d / wk) sessions alternated continuous (75% VO2 peak) and interval exercise (30 s, 2 min, and 4 min) and were completed on a supine cycle ergometer and vertical treadmill, respectively. Muscle volumes of the upper leg were calculated pre, mid, and post-BR using magnetic resonance imaging. Maximal isometric force (MIF), rate of force development (RFD), and peak power of the lower body extensors were measured twice before BR (averaged to represent pre) and once post BR. ANOVA with repeated measures and a priori planned contrasts were used to test for differences. RESULTS: There were no changes to quadriceps, hamstring, and adductor muscle volumes at mid and post BR time points compared to pre BR (Table 1). Peak power increased significantly from 1614 +/- 372 W to 1739 +/- 359 W post BR (+7.7%, p = 0.035). Neither MIF (pre: 1676 +/- 320 N vs. post: 1711 +/- 250 N, +2.1%, p = 0.333) nor RFD (pre: 7534 +/- 1265 N/ms vs. post: 6951 +/- 1241 N/ms, -7.7%, p = 0.136) were significantly impaired post BR.

  11. Stairway to heaven: evaluating levels of biological organization correlated with the successful ascent of natural waterfalls in the Hawaiian stream goby Sicyopterus stimpsoni.

    PubMed

    Schoenfuss, Heiko L; Maie, Takashi; Moody, Kristine N; Lesteberg, Kelsey E; Blob, Richard W; Schoenfuss, Tonya C

    2013-01-01

    Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels of biological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish Sicyopterus stimpsoni collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes in body shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbing muscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicus revealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations. Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing.

  12. Stairway to Heaven: Evaluating Levels of Biological Organization Correlated with the Successful Ascent of Natural Waterfalls in the Hawaiian Stream Goby Sicyopterus stimpsoni

    PubMed Central

    Schoenfuss, Heiko L.; Maie, Takashi; Moody, Kristine N.; Lesteberg, Kelsey E.; Blob, Richard W.; Schoenfuss, Tonya C.

    2013-01-01

    Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels of biological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish Sicyopterus stimpsoni collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes in body shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbing muscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicus revealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations. Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing. PMID:24386424

  13. Brain activity related to phonation in young patients with adductor spasmodic dysphonia.

    PubMed

    Kiyuna, Asanori; Maeda, Hiroyuki; Higa, Asano; Shingaki, Kouta; Uehara, Takayuki; Suzuki, Mikio

    2014-06-01

    This study investigated the brain activities during phonation of young patients with adductor spasmodic dysphonia (ADSD) of relatively short disease duration (<10 years). Six subjects with ADSD of short duration (mean age: 24. 3 years; mean disease duration: 41 months) and six healthy controls (mean age: 30.8 years) underwent functional magnetic resonance imaging (fMRI) using a sparse sampling method to identify brain activity during vowel phonation (/i:/). Intragroup and intergroup analyses were performed using statistical parametric mapping software. Areas of activation in the ADSD and control groups were similar to those reported previously for vowel phonation. All of the activated areas were observed bilaterally and symmetrically. Intergroup analysis revealed higher brain activities in the SD group in the auditory-related areas (Brodmann's areas [BA] 40, 41), motor speech areas (BA44, 45), bilateral insula (BA13), bilateral cerebellum, and middle frontal gyrus (BA46). Areas with lower activation were in the left primary sensory area (BA1-3) and bilateral subcortical nucleus (putamen and globus pallidus). The auditory cortical responses observed may reflect that young ADSD patients control their voice by use of the motor speech area, insula, inferior parietal cortex, and cerebellum. Neural activity in the primary sensory area and basal ganglia may affect the voice symptoms of young ADSD patients with short disease duration. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. 76 FR 72125 - Magnuson-Stevens Fishery Conservation and Management Act Provisions; Fisheries of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... harvest of Atlantic surfclams, ocean quahogs, and sea scallop adductor muscles harvested and shucked at... below. Under this emergency rule, this area remains closed to the harvest of Atlantic surfclams, ocean... attempt to fish for, harvest, catch, or possess any bivalve shellfish, including Atlantic surfclams, ocean...

  15. Identification and Functional Characterization of the Glycogen Synthesis Related Gene Glycogenin in Pacific Oysters (Crassostrea gigas).

    PubMed

    Li, Busu; Meng, Jie; Li, Li; Liu, Sheng; Wang, Ting; Zhang, Guofan

    2017-09-06

    High glycogen levels in the Pacific oyster (Crassostrea gigas) contribute to its flavor, quality, and hardiness. Glycogenin (CgGN) is the priming glucosyltransferase that initiates glycogen biosynthesis. We characterized the full sequence and function of C. gigas CgGN. Three CgGN isoforms (CgGN-α, β, and γ) containing alternative exon regions were isolated. CgGN expression varied seasonally in the adductor muscle and gonadal area and was the highest in the adductor muscle. Autoglycosylation of CgGN can interact with glycogen synthase (CgGS) to complete glycogen synthesis. Subcellular localization analysis showed that CgGN isoforms and CgGS were located in the cytoplasm. Additionally, a site-directed mutagenesis experiment revealed that the Tyr200Phe and Tyr202Phe mutations could affect CgGN autoglycosylation. This is the first study of glycogenin function in marine bivalves. These findings will improve our understanding of glycogen synthesis and accumulation mechanisms in mollusks. The data are potentially useful for breeding high-glycogen oysters.

  16. Perioperative complications and safety of type II thyroplasty (TPII) for adductor spasmodic dysphonia.

    PubMed

    Mizoguchi, Kenji; Hatakeyama, Hiromitsu; Yanagida, Saori; Nishizawa, Noriko; Oridate, Nobuhiko; Fukuda, Satoshi; Homma, Akihiro

    2017-05-01

    Type II thyroplasty (TPII) is one of the surgical options offered in the management of adductor spasmodic dysphonia (AdSD); however, there have been no detailed reports of its safety and associated complications during the perioperative period. Our aim was to assess the complications and safety of TPII. TPII was performed for consecutive 15 patients with AdSD from April 2012 through May 2014. We examined retrospectively the perioperative complications, the degree of surgical invasion, and recovery process from surgery. All patients underwent successful surgery under only local anesthesia. Vocal fold erythema was observed in 14 patients and vocal fold edema in 10 patients; however, all of them showed complete resolution within 1 month. No patient experienced severe complications such as acute airway distress or hemorrhage. Fourteen patients were able to have oral from the 1st postoperative morning, with the remaining patient able to have oral intake from the 2nd postoperative day. In addition, no patient experienced aspiration postoperatively. In conclusion, only minor complications were observed in association with TPII in this study. No dysphagia was observed postoperatively, which is an advantage over other treatments. The results of our study suggest that TPII is a safe surgical treatment for AdSD.

  17. Mineral content of smooth scallop (Flexopecten glaber) caught Canakkale, Turkey and evaluation in terms of food safety.

    PubMed

    Berik, Nermin; Çankırılıgil, Ekrem Cem; Gül, Güzin

    2017-07-01

    In this research, one of the most promising scallop species, smooth scallop (Flexopecten glaber) was studied. According to our findings, smooth scallop has beneficial micro and macro minerals, fat and carbohydrate just before the spawning. While the ratios protein, ash and water decreased from autumn to summer, ratio of crude fat increased till reproduction season in late spring and decreased in summer (P<0.05). In digestive glands, aluminum, bromine, cadmium, calcium, chromium, copper, iron, manganese, nickel, and zinc were detected more compared to adductor muscles (P<0.05). However; boron, magnesium and potassium were found more in adductor muscles (P<0.05) and there were no significant statistically differences in cobalt and lead (P>0.05). Most of the elements in the both tissues except K and Mg increased till summer. On the other hand, two of the most toxic metals, cadmium and aluminum were mostly accumulated in the digestive gland of smooth scallop. It is recommended that; digestive gland of scallops should be removed before consuming in terms of food safety. Besides, scallops are convenient to be processed, because of easy removal muscle tissue from internal organs. Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. Effects of rigor status during high-pressure processing on the physical qualities of farm-raised abalone (Haliotis rufescens).

    PubMed

    Hughes, Brianna H; Greenberg, Neil J; Yang, Tom C; Skonberg, Denise I

    2015-01-01

    High-pressure processing (HPP) is used to increase meat safety and shelf-life, with conflicting quality effects depending on rigor status during HPP. In the seafood industry, HPP is used to shuck and pasteurize oysters, but its use on abalones has only been minimally evaluated and the effect of rigor status during HPP on abalone quality has not been reported. Farm-raised abalones (Haliotis rufescens) were divided into 12 HPP treatments and 1 unprocessed control treatment. Treatments were processed pre-rigor or post-rigor at 2 pressures (100 and 300 MPa) and 3 processing times (1, 3, and 5 min). The control was analyzed post-rigor. Uniform plugs were cut from adductor and foot meat for texture profile analysis, shear force, and color analysis. Subsamples were used for scanning electron microscopy of muscle ultrastructure. Texture profile analysis revealed that post-rigor processed abalone was significantly (P < 0.05) less firm and chewy than pre-rigor processed irrespective of muscle type, processing time, or pressure. L values increased with pressure to 68.9 at 300 MPa for pre-rigor processed foot, 73.8 for post-rigor processed foot, 90.9 for pre-rigor processed adductor, and 89.0 for post-rigor processed adductor. Scanning electron microscopy images showed fraying of collagen fibers in processed adductor, but did not show pressure-induced compaction of the foot myofibrils. Post-rigor processed abalone meat was more tender than pre-rigor processed meat, and post-rigor processed foot meat was lighter in color than pre-rigor processed foot meat, suggesting that waiting for rigor to resolve prior to processing abalones may improve consumer perceptions of quality and market value. © 2014 Institute of Food Technologists®

  19. Perceptual structure of adductor spasmodic dysphonia and its acoustic correlates.

    PubMed

    Cannito, Michael P; Doiuchi, Maki; Murry, Thomas; Woodson, Gayle E

    2012-11-01

    To examine the perceptual structure of voice attributes in adductor spasmodic dysphonia (ADSD) before and after botulinum toxin treatment and identify acoustic correlates of underlying perceptual factors. Reliability of perceptual judgments is considered in detail. Pre- and posttreatment trial with comparison to healthy controls, using single-blind randomized listener judgments of voice qualities, as well as retrospective comparison with acoustic measurements. Oral readings were recorded from 42 ADSD speakers before and after treatment as well as from their age- and sex-matched controls. Experienced judges listened to speech samples and rated attributes of overall voice quality, breathiness, roughness, and brokenness, using computer-implemented visual analog scaling. Data were adjusted for regression to the mean and submitted to principal components factor analysis. Acoustic waveforms, extracted from the reading samples, were analyzed and measurements correlated with perceptual factor scores. Four reliable perceptual variables of ADSD voice were effectively reduced to two underlying factors that corresponded to hyperadduction, most strongly associated with roughness, and hypoadduction, most strongly associated with breathiness. After treatment, the hyperadduction factor improved, whereas the hypoadduction factor worsened. Statistically significant (P<0.01) correlations were observed between perceived roughness and four acoustic measures, whereas breathiness correlated with aperiodicity and cepstral peak prominence (CPPs). This study supported a two-factor model of ADSD, suggesting perceptual characterization by both hyperadduction and hypoadduction before and after treatment. Responses of the factors to treatment were consistent with previous research. Correlations among perceptual and acoustic variables suggested that multiple acoustic features contributed to the overall impression of roughness. Although CPPs appears to be a partial correlate of perceived

  20. Differentiating between adductor and abductor spasmodic dysphonia using airflow interruption

    PubMed Central

    Hoffman, Matthew R.; Jiang, Jack J.; Rieves, Adam L.; McElveen, Kelsey A.B.; Ford, Charles N.

    2009-01-01

    Objective To measure the laryngeal resistance (RL), subglottal pressure (Ps), and mean flow rate (MFR) of adductor (ADSD) and abductor (ABSD) spasmodic dysphonia patients using the airflow interrupter. Methods The RL of six ABSD and seven ADSD patients was measured using the airflow interrupter, a noninvasive device designed to measure MFR and Ps via mechanical balloon valve interruption. Subjects performed ten trials at each of two intensity levels, with each trial consisting of a sustained /a/ during which phonation was interrupted for 500 ms. Laryngeal resistance was calculated as subglottal pressure divided by airflow. Results Mean RL for the ADSD and ABSD subtypes at 65 dB were 24.78 cmH2O/l/s and 14.51 cmH2O/l/s, respectively (p = 0.04). Mean RL at 70 dB were 40.02 cmH2O/l/s and 15.84 cmH2O/l/s (p = 0.014). Ps for the ADSD and ABSD subtypes at 65 dB were 10.23 cmH2O and 8.32 cmH2O, respectively (p = 0.582). At the 70 dB level, Ps were 12.39 cmH2O and 11.78 cmH2O (p = 0.886). MFR for the ADSD and ABSD subtypes at 65 dB were 435 ml/s and 746 ml/s (p = 0.205). Mean MFR at 70 dB were 518 ml/s and 848 ml/s (p = 0.198). Conclusion Noninvasive measurements of RL may be useful for differentiating between ADSD and ABSD. This simple objective test which produces a quantitative output could be used to evaluate laryngeal function in patients with spasmodic dysphonia. PMID:19554636

  1. Acoustic and Perceptual Analyses of Adductor Spasmodic Dysphonia in Mandarin-speaking Chinese.

    PubMed

    Chen, Zhipeng; Li, Jingyuan; Ren, Qingyi; Ge, Pingjiang

    2018-02-12

    The objective of this study was to examine the perceptual structure and acoustic characteristics of speech of patients with adductor spasmodic dysphonia (ADSD) in Mandarin. Case-Control Study MATERIALS AND METHODS: For the estimation of dysphonia level, perceptual and acoustic analysis were used for patients with ADSD (N = 20) and the control group (N = 20) that are Mandarin-Chinese speakers. For both subgroups, a sustained vowel and connected speech samples were obtained. The difference of perceptual and acoustic parameters between the two subgroups was assessed and analyzed. For acoustic assessment, the percentage of phonatory breaks (PBs) of connected reading and the percentage of aperiodic segments and frequency shifts (FS) of vowel and reading in patients with ADSD were significantly worse than controls, the mean harmonics-to-noise ratio and the fundamental frequency standard deviation of vowel as well. For perceptual evaluation, the rating of speech and vowel in patients with ADSD are significantly higher than controls. The percentage of aberrant acoustic events (PB, frequency shift, and aperiodic segment) and the fundamental frequency standard deviation and mean harmonics-to-noise ratio were significantly correlated with the perceptual rating in the vowel and reading productions. The perceptual and acoustic parameters of connected vowel and reading in patients with ADSD are worse than those in normal controls, and could validly and reliably estimate dysphonia of ADSD in Mandarin-speaking Chinese. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  2. Tridimensional assessment of adductor spasmodic dysphonia pre- and post-treatment with Botulinum toxin.

    PubMed

    Dejonckere, P H; Neumann, K J; Moerman, M B J; Martens, J P; Giordano, A; Manfredi, C

    2012-04-01

    Spasmodic dysphonia voices form, in the same way as substitution voices, a particular category of dysphonia that seems not suited for a standardized basic multidimensional assessment protocol, like the one proposed by the European Laryngological Society. Thirty-three exhaustive analyses were performed on voices of 19 patients diagnosed with adductor spasmodic dysphonia (SD), before and after treatment with Botulinum toxin. The speech material consisted of 40 short sentences phonetically selected for constant voicing. Seven perceptual parameters (traditional and dedicated) were blindly rated by a panel of experienced clinicians. Nine acoustic measures (mainly based on voicing evidence and periodicity) were achieved by a special analysis program suited for strongly irregular signals and validated with synthesized deviant voices. Patients also filled in a VHI-questionnaire. Significant improvement is shown by all three approaches. The traditional GRB perceptual parameters appear to be adequate for these patients. Conversely, the special acoustic analysis program is successful in objectivating the improved regularity of vocal fold vibration: the basic jitter remains the most valuable parameter, when reliably quantified. The VHI is well suited for the voice-related quality of life. Nevertheless, when considering pre-therapy and post-therapy changes, the current study illustrates a complete lack of correlation between the perceptual, acoustic, and self-assessment dimensions. Assessment of SD-voices needs to be tridimensional.

  3. Biomechanical Evaluation of Different Musculoskeletal Arrangements in Psittacosaurus and Implications for Cranial Function.

    PubMed

    Taylor, Adam C; Lautenschlager, Stephan; Qi, Zhao; Rayfield, Emily J

    2017-01-01

    The masseter muscle complex is a unique feature of extant mammals and their advanced cynodont precursors, originating from the zygomatic arch and inserting onto the lateral surface of the dentary. This muscle complex is absent in sauropsids, with the exception of the neomorphic m. pseudomasseter complex that is unique to psittaciform birds (parrots and cockatiels). The anterior position and anterodorsally inclined line of action of both muscle groups increases leverage of the jaw and is thought to contribute to increased bite force, particularly in psittaciforms. A corollary is that in mammals at least, the masseter places increased load on the zygomatic arch, which may be withstood by soft tissue temporal fascia. Recently the existence of a m. pseudomasster (mPSM) and m. adductor mandibulae externus ventralis (mAMEV) has been proposed in the ornithischian dinosaur Psittacosaurus. Here we use computed tomography, digital restoration of skull anatomy and adductor musculature and computational biomechanics to test how the presence of anterodorsally inclined muscle loads influences stress, strain, deformation and estimated bite forces in the skull of Psittacosaurus. We find that the m. pseudomasseter and m. amev increases bite force with an associated increase in cranial stress and deformation. There is, however, limited osteological evidence for the existence of these two additional muscles in the psittacosaur skull and geometric morphometric informed sensitivity analysis of our finite element models shows that bite position has a greater effect on loading-induced deformation than muscle loading or material property variation. Anat Rec, 300:49-61, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Feeding biomechanics of the cownose ray, Rhinoptera bonasus, over ontogeny

    PubMed Central

    Kolmann, Matthew A; Huber, Daniel R; Motta, Philip J; Grubbs, R Dean

    2015-01-01

    Growth affects the performance of structure, so the pattern of growth must influence the role of a structure and an organism. Because animal performance is linked to morphological specialization, ontogenetic change in size may influence an organism's biological role. High bite force generation is presumably selected for in durophagous taxa. Therefore, these animals provide an excellent study system for investigating biomechanical consequences of growth on performance. An ontogenetic series of 27 cownose rays (Rhinoptera bonasus) were dissected in order to develop a biomechanical model of the feeding mechanism, which was then compared with bite forces measured from live rays. Mechanical advantage of the feeding apparatus was generally conserved throughout ontogeny, while an increase in the mass and cross-sectional area of the jaw adductors resulted in allometric gains in bite force generation. Of primary importance to forceful biting in this taxon is the use of a fibrocartilaginous tendon associated with the insertion of the primary jaw adductor division. This tendon may serve to redirect muscle forces anteriorly, transmitting them within the plane of biting. Measured bite forces obtained through electrostimulation of the jaw adductors in live rays were higher than predicted, possibly due to differences in specific tension of actual batoid muscle and that used in the model. Mass-specific bite forces in these rays are the highest recorded for elasmobranchs. Cownose rays exemplify a species that, through allometric growth of bite performance and morphological novelties, have expanded their ecological performance over ontogeny. PMID:26183820

  5. Biochemical response of the mussel Mytilus coruscus (Mytiloida: Mytilidae) exposed to in vivo sub-lethal copper concentrations

    NASA Astrophysics Data System (ADS)

    Li, Yifeng; Gu, Zhongqi; Liu, Hong; Shen, Heding; Yang, Jinglong

    2012-09-01

    Many aquatic organisms are negatively affected by exposure to high copper concentrations. We investigated the biochemical response of the mussel Mytilus coruscus (Mytiloida: Mytilidae) to copper exposure. In vivo bioassays using M. coruscus and different copper concentrations were conducted. The activity of six biomarkers, namely superoxide dismutase (SOD), catalase (CAT), acid phosphatase (ACP), alkaline phosphatase (AKP), glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were measured. Survival rates decreased with increased copper concentrations and exposure times. The LC50 values at 48, 72, and 96 h exposure were 0.48, 0.37, and 0.32 mg/L, respectively. Within digestive glands, CAT activity increased with increasing Cu concentrations. The activity of AKP showed no significant change, while the remaining four enzymes showed decreasing activity with increasing Cu concentrations. Within the gills, AKP activity increased when the Cu concentration was 0.05 mg/L, but showed no significant changes at higher concentrations. Activity of CAT and ACP within gills tended to decrease with increasing Cu concentration. The activity of SOD and GPT decreased at an exposure concentration of 0.2 mg/L. GOT activity within gills decreased at 0.1 mg/L and increased at an exposure concentration of 0.2 mg/L. Within the adductor muscle, AKP activity increased at 0.05 mg/L but did not change at higher exposure concentrations. ACP activity within adductor muscle tissue showed no change, while activities of CAT, GOT and GPT decreased with increasing Cu concentrations. SOD activity within the adductor muscle tissue significantly decreased at the 0.02, 0.05 and 0.2 mg/L exposure concentrations. Our results show tissue specific differences for the six biomarkers in for M. coruscus. Our findings provide the basis for the establishment of reference activity levels against which biomarker changes can be estimated, and are essential preliminary steps in development

  6. Muscle Deoxygenation Causes Muscle Fatigue

    NASA Technical Reports Server (NTRS)

    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.

  7. Vocal outcome after endoscopic thyroarytenoid myoneurectomy in patients with adductor spasmodic dysphonia.

    PubMed

    Gandhi, Sachin; Remacle, Marc; Mishra, Prasun; Desai, Vrushali

    2014-12-01

    Spasmodic dysphonia (SD) remains one of the most difficult of laryngeal pathologies to treat. With limited role for speech therapy, various surgical modalities have been tried with various success rates. The objective of the study is to report the results of vocal outcome after thyroarytenoid myoneurectomy in patients of adductor spasmodic dysphonia (ASD). 15 patients of ASD were selected. GRBAS, and voice handicap index (VHI) were used for perceptual evaluation of voice. Thyroarytenoid myoneurectomy was performed by vaporizing the muscular layer of the vocal fold with CO2 laser, at an intensity of 6 W with 1.2 mm diameter in scanner mode. Voice analysis was repeated at 12, 24 and 48 months follow-up. Preoperative GRBAS scores and VHI score of all the patients were poor. At 12 months 12/15 (80 %) patients having strain score of 0. There was marked improvement in VHI scores at 6 months. 10/15 (67 %) patients have been followed up for 24 months. 5/10 (50 %) patients have strain (S) value of 0. VHI scoring of 5/10 (50 %) patients was <30. Two of the four patients completed 48 months follow-up had a strain (S) value of 0, one patient has strain value of 1 and one patient had strain value of 2. 2/4 patients had VHI score of <30; one patient had that of 40. Trans-oral CO2 laser thyroarytenoid myoneurectomy shows significant long-term improvement in voice quality in terms of reduced speech brakes, effort and strain in voice.

  8. Scapular Stabilization and Muscle Strength in Manual Wheelchair Users with Spinal Cord Injury and Subacromial Impingement.

    PubMed

    Wilbanks, Susan R; Bickel, C Scott

    2016-01-01

    Background: Manual wheelchair users with spinal cord injury (SCI) are frequently diagnosed with subacromial impingement. Objective: To determine whether the pattern of muscle imbalance and impaired scapular stabilization in able-bodied (AB) adults with impingement is different from that in manual wheelchair users with SCI and impingement. Methods: The following measurements were collected from 22 adults with subacromial impingement (11 SCI, 11 AB): ratio of normalized muscle electrical activity of upper and lower trapezius (UT:LT) during arm abduction; force during abduction, adduction, internal rotation, external rotation, and push and pull; ratios of force for abduction to adduction (AB:ADD), internal to external rotation (IR:ER), and push to pull (PUSH:PULL). Results: Shoulders with impingement had significantly higher UT:LT activation (1.46 ± 0.52) than shoulders without impingement (0.93 ± 0.45) ( P = .006), regardless of wheelchair user status. Significant differences between AB participants and those with SCI were observed for ABD:ADD ( P = .005), PUSH:PULL ( P = .012), and pull strength ( P = .043). Participants with SCI had a significantly greater ABD:ADD (1.37 ± 0.36) than AB participants (1.04 ± 0.22) ( P = .002) and a significantly greater PUSH:PULL (1.53 ± 0.36) than AB participants (1.26 ± 0.18) ( P = .005) because of decreased strength in adduction ( P = .021) and pull ( P = .013). Conclusions: Strategies targeting the posterior shoulder girdle for AB adults are appropriate for manual wheelchair users with SCI and impingement and should focus on scapular retractors and arm adductors with emphasis on scapular depression and posterior tilting.

  9. Molecular cloning, characterization, and expression analysis of a heat shock protein (HSP) 70 gene from Paphia undulata.

    PubMed

    Wu, Xiangwei; Tan, Jing; Cai, Mingyi; Liu, Xiande

    2014-06-15

    In this study, a full-length HSP70 cDNA from Paphia undulata was cloned using reverse transcriptase polymerase chain reaction (RT-PCR) coupled with rapid amplification of cDNA ends (RACE). The full-length cDNA is 2,351 bp, consisting of a 5'-untranslated region (UTR) of 83 bp, a 3'-UTR of 315 bp, and an open reading frame (ORF) of 1,953 bp. This cDNA encodes 650 amino acids with an estimated molecular weight of 71.3 kDa and an isoelectric point of 5.51. Based on the amino acid sequence analysis and phylogenetic analysis, this HSP70 gene was identified as a member of the cytoplasmic HSP70 family, being the constitutive expression, and it was designated as PuHSC70. The distribution of PuHSC70 mRNA in the mantle, digestive gland, adductor muscle, gonad, gill, heart, and hemocytes suggested that PuHSC70 is ubiquitously expressed. The mRNA levels of PuHSC70 under high temperature and high salinity stresses were analyzed by real-time PCR. Under high temperature stress of 32°C, PuHSC70 mRNA in the mantle, digestive gland, gill, and heart was significantly up-regulated at 1h and 2h, and it was then progressively down-regulated. In the adductor muscle, the level of PuHSC70 mRNA gradually increased throughout the study period; the mRNA levels in the gonad and hemocytes increased significantly at 4h and 8h (P<0.05) and then decreased at 8h and 14 h, respectively, however they increased again afterwards, reaching the highest levels at 50h. Under high salinity (32 ‰) stress, the mRNA levels of PuHSC70 in the mantle and gonad were increased significantly only at 24h and 48 h (P<0.05), and at the rest of the study period they were slightly elevated. Compared with the pretreatment level, the levels of expression in the digestive gland and gill were unchanged or reduced throughout the study period. The levels of PuHSC70 mRNA in the adductor muscle, hemocytes, and heart were significantly increased, reaching a maximum at 24h, and then they gradually decreased; moreover, in the

  10. The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea) and skull shape in Testudines.

    PubMed

    Jones, Marc E H; Werneburg, Ingmar; Curtis, Neil; Penrose, Rod; O'Higgins, Paul; Fagan, Michael J; Evans, Susan E

    2012-01-01

    Sea turtles (Chelonoidea) are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii), for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex.

  11. Pectoral nerves I block is associated with a significant motor blockade with no dermatomal sensory changes: a prospective volunteer randomized-controlled double-blind study.

    PubMed

    Desroches, Jean; Belliveau, Marc; Bilodeau, Carole; Landry, Michel; Roy, Maxim; Beaulieu, Pierre

    2018-03-29

    The pectoral nerves (PECS) I block, first described in 2011 for surgery involving the pectoralis muscle, has principally been used for breast cancer surgery. No formal evaluation of its differential motor- and sensory-blocking abilities has been reported. We hypothesize that the PECS I block will produce a motor block of the pectoralis muscles with diminished upper limb adduction strength as measured with a handheld dynamometer. We conducted a PECS I block in a randomized placebo-controlled trial in six healthy subjects who received 0.4 mL·kg -1 of 0.9% saline (placebo) on one side and bupivacaine (0.25% with 1:400 000 epinephrine) on the other. We measured both upper limb adduction strength with a dynamometer and sensory skin levels over the thorax. The mean (standard deviation [SD]) adductor strength evaluated before the block was 119.4 (20.7) Newtons (N). After the PECS I block with bupivacaine, the mean (SD) strength of 54.2 (16.3) N was compared with 116.0 (30.4) N in the placebo group (difference in means 61.8 N; 95% confidence interval [CI], 27.8 to 95.8 N; P = 0.005), showing a 54.6% (95% CI, 43.6 to 65.6%) reduction in adductor strength. There was no difference in dermatomal skin sensory testing between the placebo and bupivacaine sides. This study shows that a PECS I block produces motor blockade as shown by reduced upper limb adductor strength without any overlying dermatomal sensory loss. www.clinicaltrials.gov (NCT03040167) 2 February 2017.

  12. Botulinum toxin treatment of false vocal folds in adductor spasmodic dysphonia: Functional outcomes.

    PubMed

    Simpson, C Blake; Lee, Christopher T; Hatcher, Jeanne L; Michalek, Joel

    2016-01-01

    Supraglottic injection of botulinum toxin (Botox) has been described as an effective treatment for adductor spasmodic dysphonia (ADSD). Anecdotal evidence suggests that the patients have little to no breathiness after injection, but no formal longitudinal studies have been carried out to date. The purpose of this study was to examine the voice outcomes in patients with ADSD after supraglottic Botox injection. Retrospective case series. Patients with ADSD who were treated with supraglottic Botox injections completed a qualitative self-evaluation of voice function after injection using the percentage of normal function (PNF) scale, a validated, quantitative scale from 0% (no function) to 100% (normal function). Posttreatment voice improvement after injection was determined using a Voice Handicap Index-10 (VHI-10) questionnaire. A total of 198 supraglottic injections were performed between July 2011 and October 2014. Twenty-five questionnaires were completed. Mean postinjection PNF was 95.0% ± 8.4% and was significantly increased from the preinjection mean PNF (62.5%) ± 22.6% (P < 0.001). The mean best VHI-10 for all injections was 7.23. In 19 of 25 patients (76%), there was no reduction in PNF in the early postinjection period. In the remaining six patients (24%), the decline in mean vocal function was 9.2%. Supraglottic Botox injection is an effective treatment for ADSD. Postinjection voice is significantly improved, and the majority of patients do not experience breathy voice/decline in vocal function after injection. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  13. An Integrated Musculoskeletal Countermeasure Battery for Long-Duration Lunar Missions

    NASA Technical Reports Server (NTRS)

    Lang, T. F.; Streeper, T. S.; Cavanagh, P. R.; Saeed, I. H.; Carpenter, R. D.; Frassetto, L. A.; Lee, S. M. C.; Grodsinsky, C. M.; Funk, J.; Hanson, A. M.; hide

    2011-01-01

    During extended periods of skeletal unloading, losses in strength and density of the proximal femur will occur. In long-duration spaceflight, resistive exercise is used to replace the normal loads exerted on the spine and hip. At the present time, there is no conclusive evidence that hip bone loss has been prevented in this scenario. Our group has recently developed and clinically evaluated a multifunctional exercise system, the Combined Countermeasure Device (CCD). The CCD comprises a low-footprint Stuart Platform for lower-body resistance exercise and balance training, and a cardiovascular exercise bicycle. A consideration for resistance exercise was targeting of the hip abductor and adductor muscles, which attach directly at the hip and which should subject it to the largest loads. In our training study, we found that CCD exercise increased hip adductor and abductor strength, and modeling results suggest that this exercise exerts forces on the hip of approx. 4-6 body weights at 1g, compared to forces of approx.2.5 body weight y squatting exercise. In our current study, we hypothesize that abductor and adductor exercise will increase the density and strength of the proximal femur.

  14. EMG activity across gait and incline: The impact of muscular activity on human morphology

    PubMed Central

    Wall-Scheffler, Cara M.; Chumanov, Elizabeth; Steudel-Numbers, Karen; Heiderscheit, Bryan

    2010-01-01

    The study of human evolution depends upon a fair assessment of the ability of hominin individuals to gain access to necessary resources. We expect that the morphology of extant and extinct populations represents a successful locomotory system that allowed individuals to move across the environment gaining access to food, water and mates while still maintaining excess energy to allocate to reproduction. Our assessment of locomotor morphology must then incorporate tests of fitness within realistic environments—environments that themselves vary in terrain and whose negotiation requires a variety of gait and speeds. This study assesses muscular activity (measured as the integrated signal from surface electromyography) of seven thigh and hip muscle groups during walking and running across a wide range of speeds and inclines, in order to systematically assess the role that morphology can play in minimizing muscular activity and thus energy expenditure. Our data suggest that humans are better adapted to walking than running at any slope, as evidenced by small confidence intervals and even trends across speed and incline. We find that while increasing task intensity unsurprisingly increases muscular activity in the lower limb, individuals with longer limbs show significantly reduced activity during both walking and running, especially in the hip adductors, gluteus maximus and hamstring muscles. People with a broader pelvis show significantly reduced activity while walking in the hip adductor and hamstring muscles. PMID:20623603

  15. Molecular characterization and expression analysis of the myostatin gene and its association with growth traits in Noble scallop (Chlamys nobilis).

    PubMed

    Fan, Sigang; Xu, Youhou; Liu, Baosuo; He, Wenyao; Zhang, Bo; Su, Jiaqi; Yu, Dahui

    2017-10-01

    Myostatin (MSTN), also called growth and differentiation factor-8 (GDF-8), is a member of the transforming growth factor-β (TGF-β) superfamily and an inhibitor of muscle differentiation and growth. In this report, we identified and characterized a MSTN gene (CnMSTN) from the scallop Chlamys nobilis. The open reading frame of CnMSTN was 1374bp in length, encoding 457 amino acids. The structure of CnMSTN included a putative signal peptide, a TGF-β propeptide domain, and a conserved TGF-β domain. Phylogenetic analysis showed that the CnMSTN gene was clustered in the same subgroup with the MSTN gene found in Mollusca. Quantitative real-time PCR showed that the CnMSTN gene was widely expressed in all tissues tested, with the highest expression level observed in the adductor muscle. Six single nucleotide polymorphisms (SNPs) were identified in the promoter region, but no SNP was detected in the exon regions. Association analysis showed that SNP g.-579A/C had significant effects on body mass, soft-tissue mass, and adductor muscle mass. The CC and AC genotypes of g.-579A/C had significantly higher growth trait values than that of genotype AA (P<0.05). These results suggest that CnMSTN could be used as a candidate gene for the selective breeding of C. nobilis. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Accommodation: The role of the external muscles of the eye: A consideration of refractive errors in relation to extraocular malfunction.

    PubMed

    Hargrave, B K

    2014-11-01

    Speculation as to optical malfunction has led to dissatisfaction with the theory that the lens is the sole agent in accommodation and to the suggestion that other parts of the eye are also conjointly involved. Around half-a-century ago, Robert Brooks Simpkins suggested that the mechanical features of the human eye were precisely such as to allow for a lengthening of the globe when the eye accommodated. Simpkins was not an optical man but his theory is both imaginative and comprehensive and deserves consideration. It is submitted here that accommodation is in fact a twofold process, and that although involving the lens, is achieved primarily by means of a give - and - take interplay between adducting and abducting external muscles, whereby an elongation of the eyeball is brought about by a stretching of the delicate elastic fibres immediately behind the cornea. The three muscles responsible for convergence (superior, internal and inferior recti) all pull from in front backwards, while of the three abductors (external rectus and the two obliques) the obliques pull from behind forwards, allowing for an easy elongation as the eye turns inwards and a return to its original length as the abducting muscles regain their former tension, returning the eye to distance vision. In refractive errors, the altered length of the eyeball disturbs the harmonious give - and - take relationship between adductors and abductors. Such stresses are likely to be perpetuated and the error exacerbated. Speculation is not directed towards a search for a possible cause of the muscular imbalance, since none is suspected. Muscles not used rapidly lose tone, as evidenced after removal of a limb from plaster. Early attention to the need for restorative exercise is essential and results usually impressive. If flexibility of the external muscles of the eyes is essential for continuing good sight, presbyopia can be avoided and with it the supposed necessity of glasses in middle life. Early attention

  17. Intralaryngeal neuroanatomy of the recurrent laryngeal nerve of the rabbit

    PubMed Central

    Ryan, Stephen; McNicholas, Walter T; O'Regan, Ronan G; Nolan, Philip

    2003-01-01

    We undertook this study to determine the detailed neuroanatomy of the terminal branches of the recurrent laryngeal nerve (RLN) in the rabbit to facilitate future neurophysiological recordings from identified branches of this nerve. The whole larynx was isolated post mortem in 17 adult New Zealand White rabbits and prepared using a modified Sihler's technique, which stains axons and renders other tissues transparent so that nerve branches can be seen in whole mount preparations. Of the 34 hemi-laryngeal preparations processed, 28 stained well and these were dissected and used to characterize the neuroanatomy of the RLN. In most cases (23/28) the posterior cricoarytenoid muscle (PCA) was supplied by a single branch arising from the RLN, though in five PCA specimens there were two or three separate branches to the PCA. The interarytenoid muscle (IA) was supplied by two parallel filaments arising from the main trunk of the RLN rostral to the branch(es) to the PCA. The lateral cricoarytenoid muscle (LCA) commonly received innervation from two fine twigs branching from the RLN main trunk and travelling laterally towards the LCA. The remaining fibres of the RLN innervated the thyroarytenoid muscle (TA) and comprised two distinct branches, one supplying the pars vocalis and the other branching extensively to supply the remainder of the TA. No communicating anastomosis between the RLN and superior laryngeal nerve within the larynx was found. Our results suggest it is feasible to make electrophysiological recordings from identified terminal branches of the RLN supplying laryngeal adductor muscles separate from the branch or branches to the PCA. However, the very small size of the motor nerves to the IA and LCA suggests that it would be very difficult to record selectively from the nerve supply to individual laryngeal adductor muscles. PMID:12739619

  18. Normative values of hip strength in adult male association football players assessed by handheld dynamometry.

    PubMed

    Hanna, Chris M; Fulcher, Mark L; Elley, C Raina; Moyes, Simon A

    2010-05-01

    Chronic groin pain is a common problem in association football players. Normative values for the strength of hip muscles, measured in an accurate and accessible manner, are needed to gauge strength and inform return to play decisions in this group. The purpose of this study was to define normative values of hip muscle strength using handheld dynamometry. A series of reliable clinical tests that are commonly used when making return to sport decisions in athletes with chronic adductor related groin pain have been selected. One hundred and twenty adult male association football players, free from injury, were recruited. Isometric strength of the hip flexors and adductor muscles was measured using a handheld dynamometer. Mean age was 24.9 years (SD 5.9). Eighty participants (67%) had experienced groin pain in the past. Mean strength for dominant leg hip flexion was 47.3 kg (95% confidence interval 45.6-49.0), non-dominant leg hip flexion was 42.5 kg (41.1-43.9), adduction at 0 degrees hip flexion was 35.6 kg (34.1-37.1), adduction at 45 degrees was 32.0 kg (30.9-33.1), and adduction at 90 degrees was 25.5 kg (24.4-26.5). This study establishes reference ranges and predictive equations for maximal isometric contraction strength of the hip muscles in non-injured adult male association football players. This information will assist assessment and management of an athlete's return to play following injury. 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. The cross-tissue metabolic response of abalone (Haliotis midae) to functional hypoxia.

    PubMed

    Venter, Leonie; Loots, Du Toit; Mienie, Lodewyk J; Jansen van Rensburg, Peet J; Mason, Shayne; Vosloo, Andre; Lindeque, Jeremie Z

    2018-03-23

    Functional hypoxia is a stress condition caused by the abalone itself as a result of increased muscle activity, which generally necessitates the employment of anaerobic metabolism if the activity is sustained for prolonged periods. With that being said, abalone are highly reliant on anaerobic metabolism to provide partial compensation for energy production during oxygen-deprived episodes. However, current knowledge on the holistic metabolic response for energy metabolism during functional hypoxia, and the contribution of different metabolic pathways and various abalone tissues towards the overall accumulation of anaerobic end-products in abalone are scarce. Metabolomics analysis of adductor muscle, foot muscle, left gill, right gill, haemolymph and epipodial tissue samples indicated that South African abalone ( Haliotis midae) subjected to functional hypoxia utilises predominantly anaerobic metabolism, and depends on all of the main metabolite classes (proteins, carbohydrates and lipids) for energy supply. Functional hypoxia caused increased levels of anaerobic end-products: lactate, alanopine, tauropine, succinate and alanine. Also, elevation in arginine levels was detected, confirming that abalone use phosphoarginine to generate energy during functional hypoxia. Different tissues showed varied metabolic responses to hypoxia, with functional hypoxia showing excessive changes in the adductor muscle and gills. From this metabolomics investigation, it becomes evident that abalone are metabolically able to produce sufficient amounts of energy when functional hypoxia is experienced. Also, tissue interplay enables the adjustment of H. midae energy requirements as their metabolism shifts from aerobic to anaerobic respiration during functional hypoxia.This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

  20. The cross-tissue metabolic response of abalone (Haliotis midae) to functional hypoxia

    PubMed Central

    Venter, Leonie; Loots, Du Toit; Mienie, Lodewyk J.; Jansen van Rensburg, Peet J.; Mason, Shayne; Vosloo, Andre

    2018-01-01

    ABSTRACT Functional hypoxia is a stress condition caused by the abalone itself as a result of increased muscle activity, which generally necessitates the employment of anaerobic metabolism if the activity is sustained for prolonged periods. With that being said, abalone are highly reliant on anaerobic metabolism to provide partial compensation for energy production during oxygen-deprived episodes. However, current knowledge on the holistic metabolic response for energy metabolism during functional hypoxia, and the contribution of different metabolic pathways and various abalone tissues towards the overall accumulation of anaerobic end-products in abalone are scarce. Metabolomics analysis of adductor muscle, foot muscle, left gill, right gill, haemolymph and epipodial tissue samples indicated that South African abalone (Haliotis midae) subjected to functional hypoxia utilises predominantly anaerobic metabolism, and depends on all of the main metabolite classes (proteins, carbohydrates and lipids) for energy supply. Functional hypoxia caused increased levels of anaerobic end-products: lactate, alanopine, tauropine, succinate and alanine. Also, elevation in arginine levels was detected, confirming that abalone use phosphoarginine to generate energy during functional hypoxia. Different tissues showed varied metabolic responses to hypoxia, with functional hypoxia showing excessive changes in the adductor muscle and gills. From this metabolomics investigation, it becomes evident that abalone are metabolically able to produce sufficient amounts of energy when functional hypoxia is experienced. Also, tissue interplay enables the adjustment of H. midae energy requirements as their metabolism shifts from aerobic to anaerobic respiration during functional hypoxia. This article has an associated First Person interview with the first author of the paper. PMID:29572259

  1. FGF and TGFβ signaling link form and function during jaw development and evolution.

    PubMed

    Woronowicz, Katherine C; Gline, Stephanie E; Herfat, Safa T; Fields, Aaron J; Schneider, Richard A

    2018-05-16

    How does form arise during development and change during evolution? How does form relate to function, and what enables embryonic structures to presage their later use in adults? To address these questions, we leverage the distinct functional morphology of the jaw in duck, chick, and quail. In connection with their specialized mode of feeding, duck develop a secondary cartilage at the tendon insertion of their jaw adductor muscle on the mandible. An equivalent cartilage is absent in chick and quail. We hypothesize that species-specific jaw architecture and mechanical forces promote secondary cartilage in duck through the differential regulation of FGF and TGFβ signaling. First, we perform transplants between chick and duck embryos and demonstrate that the ability of neural crest mesenchyme (NCM) to direct the species-specific insertion of muscle and the formation of secondary cartilage depends upon the amount and spatial distribution of NCM-derived connective tissues. Second, we quantify motility and build finite element models of the jaw complex in duck and quail, which reveals a link between species-specific jaw architecture and the predicted mechanical force environment. Third, we investigate the extent to which mechanical load mediates FGF and TGFβ signaling in the duck jaw adductor insertion, and discover that both pathways are mechano-responsive and required for secondary cartilage formation. Additionally, we find that FGF and TGFβ signaling can also induce secondary cartilage in the absence of mechanical force or in the adductor insertion of quail embryos. Thus, our results provide novel insights on molecular, cellular, and biomechanical mechanisms that couple musculoskeletal form and function during development and evolution. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  2. The Head and Neck Anatomy of Sea Turtles (Cryptodira: Chelonioidea) and Skull Shape in Testudines

    PubMed Central

    Jones, Marc E. H.; Werneburg, Ingmar; Curtis, Neil; Penrose, Rod; O’Higgins, Paul; Fagan, Michael J.; Evans, Susan E.

    2012-01-01

    Background Sea turtles (Chelonoidea) are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. Methodology/Principal Findings Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempii), for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. Conclusions/Significance In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex. PMID:23144831

  3. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    PubMed Central

    Randolph, Matthew E.; Pavlath, Grace K.

    2015-01-01

    The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies (MDs), such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some MDs. The biology of muscle stem cells varies depending on the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease. PMID:26500547

  4. Brain Activity in Patients With Adductor Spasmodic Dysphonia Detected by Functional Magnetic Resonance Imaging.

    PubMed

    Kiyuna, Asanori; Kise, Norimoto; Hiratsuka, Munehisa; Kondo, Shunsuke; Uehara, Takayuki; Maeda, Hiroyuki; Ganaha, Akira; Suzuki, Mikio

    2017-05-01

    Spasmodic dysphonia (SD) is considered a focal dystonia. However, the detailed pathophysiology of SD remains unclear, despite the detection of abnormal activity in several brain regions. The aim of this study was to clarify the pathophysiological background of SD. This is a case-control study. Both task-related brain activity measured by functional magnetic resonance imaging by reading the five-digit numbers and resting-state functional connectivity (FC) measured by 150 T2-weighted echo planar images acquired without any task were investigated in 12 patients with adductor SD and in 16 healthy controls. The patients with SD showed significantly higher task-related brain activation in the left middle temporal gyrus, left thalamus, bilateral primary motor area, bilateral premotor area, bilateral cerebellum, bilateral somatosensory area, right insula, and right putamen compared with the controls. Region of interest voxel FC analysis revealed many FC changes within the cerebellum-basal ganglia-thalamus-cortex loop in the patients with SD. Of the significant connectivity changes between the patients with SD and the controls, the FC between the left thalamus and the left caudate nucleus was significantly correlated with clinical parameters in SD. The higher task-related brain activity in the insula and cerebellum was consistent with previous neuroimaging studies, suggesting that these areas are one of the unique characteristics of phonation-induced brain activity in SD. Based on FC analysis and their significant correlations with clinical parameters, the basal ganglia network plays an important role in the pathogenesis of SD. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  5. Long-term Evaluation of Type 2 Thyroplasty with Titanium Bridges for Adductor Spasmodic Dysphonia.

    PubMed

    Sanuki, Tetsuji; Yumoto, Eiji

    2017-07-01

    Objectives Standard treatments of adductor spasmodic dysphonia (AdSD) provide temporary relief of symptoms. Type 2 thyroplasty offers a long-term solution; however, long-term voice outcome data are lacking. The objective of this study was to assess the long-term voice outcomes of type 2 thyroplasty with titanium bridges through use of a validated voice questionnaire. Study Design Case series with chart review. Setting University hospital. Subjects and Methods Forty-seven consecutively enrolled patients with AdSD underwent type 2 thyroplasty with titanium bridges between August 2006 and November 2014. Questionnaires were completed during regularly scheduled follow-ups and, in some cases, were sent to patients who missed follow-up appointments. In 2015, questionnaires were mailed to all 47 patients and included a Voice Handicap Index-10 evaluation, as well as questions on postoperative vocal symptoms, surgical site, and status of the implanted titanium bridges. Results Of 47 patients with AdSD, 31 (66%) completed the questionnaires. The average follow-up interval was 41.3 months. No patient reported experiencing an adverse event around the surgical site, and almost all were satisfied with their voices postoperatively. The mean postoperative (>3 years) Voice Handicap Index-10 score improved significantly, from 26.3 to 9.4 (n = 17, P = .0009). Conclusions Type 2 thyroplasty for AdSD significantly improved patient quality of life and voice symptoms and continued to do so long after the surgery. The results of this study suggest that type 2 thyroplasty provides relief from vocal symptoms in patients with AdSD for >3 years.

  6. Changes in hip and ankle range of motion and hip muscle strength in 8–11 year old novice female ballet dancers and controls: a 12 month follow up study

    PubMed Central

    Bennell, K; Khan, K; Matthews, B; Singleton, C

    2001-01-01

    Objectives—To evaluate in a 12 month longitudinal study changes in hip and ankle range of motion and hip muscle strength in young female novice ballet dancers. Methods—Fifty three of the original 77 (69%) female dancers aged 8–11 years and 40 of the original 49 (82%) controls returned for follow up measurements one year later. Supine right active hip external (ER) and internal (IR) rotation were measured using an inclinometer. A turnout protractor was used to assess standing active turnout range. Range of right weight bearing ankle dorsiflexion and calf muscle length were measured in a standing lunge position using an inclinometer. A manual muscle tester was used to assess right hip flexor, IR, ER, abductor and adductor strength. Results—The mean (SD) 12 month change in hip ER did not differ between dancers (11.7 (11.3)°) and controls (8.1 (17.6)°). Dancers gained 12.5 (13.5)° hip IR which was significantly greater than controls (0.5 (13.9)°). Greater IR change was associated with improved IR strength (r = 0.34, p<0.001). Dancers increased total turnout (12.0 (16.7)°) significantly more than controls (2.2 (20.0)°). There was no significant change in ankle dorsiflexion range in either group. Dancers and controls increased in all measures of hip muscle strength (p<0.001) and dancers achieved significantly greater gains in three out of five muscle groups (all, p<0.05). Conclusions—Total hip range of motion increased in both ballet students and controls at this young age. However, ankle dorsiflexion did not, which is probably due to this movement being blocked by bony apposition, rather than soft tissue stretch. This has implications for ballet teachers, as it has long been accepted that this movement could be improved with training. Dancers had greater increases in hip strength after 12 months compared with controls in muscles specific for ballet, suggesting that hip strength can be trained at this young age. Whether these gains are permanent requires

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

    PubMed

    Stutzig, Norman; Siebert, Tobias

    2015-08-01

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

  8. Fresh meat and further processing characteristics of ham muscles from finishing pigs fed ractopamine hydrochloride.

    PubMed

    Boler, D D; Holmer, S F; Duncan, D A; Carr, S N; Ritter, M J; Stites, C R; Petry, D B; Hinson, R B; Allee, G L; McKeith, F K; Killefer, J

    2011-01-01

    Ractopamine hydrochloride (RAC) has consistently led to an advantage in carcass cutting yields of finishing pigs and remains a common feed additive in US finishing pig diets. Less is known about the effect of RAC on further processing characteristics. Some researchers have reported advantages in ultimate pH of the LM in pigs fed RAC. If a greater ultimate pH was also observed in hams, the increased pH could affect further processing characteristics and lead to better protein interaction and improved textural properties. The objective of this experiment was to determine if RAC-fed pigs yielded hams with a greater ultimate pH, and if so, whether or not that advantage improves textural properties and water retention of further processed hams. Two hundred hams from barrows and gilts fed RAC or control diets were selected based on HCW. Hams were fabricated into 5 separate pieces to determine cutting yields, and 6 muscles were evaluated for ultimate pH. Hams were processed to make cured and smoked hams. Ractopamine increased cutting yields of the whole ham (P < 0.0001), inside (P < 0.01), outside (P < 0.01), and knuckle (P < 0.01) when expressed as a percentage of chilled side weight. Ultimate pH of the rectus femoris, vastus lateralis, and semitendinosus were all 0.06 pH units greater (P < 0.05), the biceps femoris was 0.04 pH units greater (P = 0.02), and the semimembranosus and adductor muscles were 0.03 pH units greater in pigs fed 7.4 mg/kg of RAC when compared with control pigs. Cured hams from RAC-fed pigs were heavier at all stages of production. No differences were detected in binding strengths (P = 0.88) or protein fat-free values (P = 0.13) between RAC (9.06 kg and 20.37) and control hams (9.01 kg and 20.13). Ractopamine increased cutting yields, total weight of cured hams, and ultimate muscle pH. Ractopamine can be fed to pigs to achieve the desired growth characteristic advantages and cutting yields without affecting further processed ham characteristics.

  9. Muscle-Specific Vascular Endothelial Growth Factor Deletion Induces Muscle Capillary Rarefaction Creating Muscle Insulin Resistance

    PubMed Central

    Bonner, Jeffrey S.; Lantier, Louise; Hasenour, Clinton M.; James, Freyja D.; Bracy, Deanna P.; Wasserman, David H.

    2013-01-01

    Muscle insulin resistance is associated with a reduction in vascular endothelial growth factor (VEGF) action and muscle capillary density. We tested the hypothesis that muscle capillary rarefaction critically contributes to the etiology of muscle insulin resistance in chow-fed mice with skeletal and cardiac muscle VEGF deletion (mVEGF−/−) and wild-type littermates (mVEGF+/+) on a C57BL/6 background. The mVEGF−/− mice had an ∼60% and ∼50% decrease in capillaries in skeletal and cardiac muscle, respectively. The mVEGF−/− mice had augmented fasting glucose turnover. Insulin-stimulated whole-body glucose disappearance was blunted in mVEGF−/− mice. The reduced peripheral glucose utilization during insulin stimulation was due to diminished in vivo cardiac and skeletal muscle insulin action and signaling. The decreased insulin-stimulated muscle glucose uptake was independent of defects in insulin action at the myocyte, suggesting that the impairment in insulin-stimulated muscle glucose uptake was due to poor muscle perfusion. The deletion of VEGF in cardiac muscle did not affect cardiac output. These studies emphasize the importance for novel therapeutic approaches that target the vasculature in the treatment of insulin-resistant muscle. PMID:23002035

  10. Dissociated time course between peak torque and total work recovery following bench press training in resistance trained men.

    PubMed

    Ferreira, Diogo V; Gentil, Paulo; Ferreira-Junior, João B; Soares, Saulo R S; Brown, Lee E; Bottaro, Martim

    2017-10-01

    To evaluate the time course of peak torque and total work recovery after a resistance training session involving the bench press exercise. Repeated measures with a within subject design. Twenty-six resistance-trained men (age: 23.7±3.7years; height: 176.0±5.7cm; mass: 79.65±7.61kg) performed one session involving eight sets of the bench press exercise performed to momentary muscle failure with 2-min rest between sets. Shoulder horizontal adductors peak torque (PT), total work (TW), delayed onset muscle soreness (DOMS) and subjective physical fitness were measured pre, immediately post, 24, 48, 72 and 96h following exercise. The exercise protocol resulted in significant pectoralis major DOMS that lasted for 72h. Immediately after exercise, the reduction in shoulder horizontal adductors TW (25%) was greater than PT (17%). TW, as a percentage of baseline values, was also less than PT at 24, 48 and 96h after exercise. Additionally, PT returned to baseline at 96h, while TW did not. Resistance trained men presented dissimilar PT and TW recovery following free weight bench press exercise. This indicates that recovery of maximal voluntary contraction does not reflect the capability to perform multiple contractions. Strength and conditioning professionals should be cautious when evaluating muscle recovery by peak torque, since it can lead to the repetition of a training session sooner than recommended. Copyright © 2017. Published by Elsevier Inc.

  11. Anatomical variations of the deep head of Cruveilhier of the flexor pollicis brevis and its significance for the evolution of the precision grip.

    PubMed

    Dunlap, Samuel S; Aziz, M Ashraf; Ziermann, Janine M

    2017-01-01

    Cruveilhier described in 1834 the human flexor pollicis brevis (FPB), a muscle of the thenar compartment, as having a superficial and a deep head, respectively, inserted onto the radial and ulnar sesamoids of the thumb. Since then, Cruveilhier's deep head has been controversially discussed. Often this deep head is confused with Henle's "interosseous palmaris volaris" or said to be a slip of the oblique adductor pollicis. In the 1960s, Day and Napier described anatomical variations of the insertions of Cruveilhier's deep head, including its absence, and hypothesized, that the shift of the deep head's insertion from ulnar to radial facilitated "true opposability" in anthropoids. Their general thesis for muscular arrangements underlying the power and precision grip is sound, but they did not delineate their deep head from Henle's muscle or the adductor pollicis, and their description of the attachments of Cruveilhier's deep head were too vague and not supported by a significant portion of the anatomical literature. Here, we reinvestigated Cruveilhier's deep head to resolve the controversy about it and because many newer anatomy textbooks do not describe this muscle, while it is often an obvious functionally (writing, texting, precision grip) and clinically significant thenar muscle. For the first time, we empirically delineated Cruveilhier's deep head from neighboring muscles with which it was previously confused. We observed 100% occurrence of the uncontested deep head in 80 human hands, displaying a similar variability of insertions as Day and Napier, but in significantly different numbers. Furthermore, we found variability in the origin and included as important landmarks the trapezoid and the ligamentum carpi radiatum. We tested the assertion regarding the evolutionary morphology and its role in the improvements in thumb movements during various precision grips. Our overall conclusions differ with respect to the developmental and evolutionary origin of the FPB

  12. Influence of consonant voicing characteristics on sentence production in abductor versus adductor spasmodic dysphonia.

    PubMed

    Cannito, Michael P; Chorna, Lesya B; Kahane, Joel C; Dworkin, James P

    2014-05-01

    This study evaluated the hypotheses that sentence production by speakers with adductor (AD) and abductor (AB) spasmodic dysphonia (SD) may be differentially influenced by consonant voicing and manner features, in comparison with healthy, matched, nondysphonic controls. This was a prospective, single blind study, using a between-groups, repeated measures design for the independent variables of perceived voice quality and sentence duration. Sixteen subjects with ADSD and 10 subjects with ABSD, as well as 26 matched healthy controls produced four short, simple sentences that were systematically loaded with voiced or voiceless consonants of either obstruant or continuant manner categories. Experienced voice clinicians, who were "blind" as to speakers' group affixations, used visual analog scaling to judge the overall voice quality of each sentence. Acoustic sentence durations were also measured. Speakers with ABSD or ADSD demonstrated significantly poorer than normal voice quality on all sentences. Speakers with ABSD exhibited longer than normal duration for voiceless consonant sentences. Speakers with ADSD had poorer voice quality for voiced than for voiceless consonant sentences. Speakers with ABSD had longer durations for voiceless than for voiced consonant sentences. The two subtypes of SD exhibit differential performance on the basis of consonant voicing in short, simple sentences; however, each subgroup manifested voicing-related differences on a different variable (voice quality vs sentence duration). Findings suggest different underlying pathophysiological mechanisms for ABSD and ADSD. Findings also support inclusion of short, simple sentences containing voiced or voiceless consonants as part of the diagnostic protocol for SD, with measurement of sentence duration in addition to judments of voice quality severity. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  13. Skeletal muscle

    USDA-ARS?s Scientific Manuscript database

    There are approximately 650-850 muscles in the human body these include skeletal (striated), smooth and cardiac muscle. The approximation is based on what some anatomists consider separate muscle or muscle systems. Muscles are classified based on their anatomy (striated vs. smooth) and if they are v...

  14. Muscle biopsy

    MedlinePlus

    ... muscle ( myopathic changes ) Tissue death of the muscle (necrosis) Disorders that involve inflammation of the blood vessels and affect muscles ( necrotizing vasculitis ) Traumatic muscle damage ...

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

    PubMed

    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.

  16. Parasites and pathological condition in Green mussel Perna viridis Linnaeus, 1758 from western Johor Straits, Malaysia

    NASA Astrophysics Data System (ADS)

    Azmi, Nur-Fauzana; Ghaffar, Mazlan Abd.; Cob, Zaidi Che

    2018-04-01

    This study describes the parasites and pathological condition of infected organ of the green mussel Perna viridis from Merambong Shoal, Western Johor Straits, Malaysia. Samples were collected randomly in November and December 2013. Histopathology techniques using Masson's Trichrome staining protocol were performed and the thin sections were observed under light microscope. Result showed that gonad was the most infected organ followed by the digestive tubule, adductor muscle, intestine and mantle tissue. The parasites (apicomplexa) such as spore-like Nematopsis, macrogamont-like coccidian, mature oocyst-like coccidian, unidentified coccidian and protozoan were found in the adductor muscle, gonad and mantle. Meanwhile, the pathological conditions were found in all infected organs except the gill, such as particular melanin deposits in cytoplasm, Rickettsia-like or Chlamydiae organism and bacteria-like inclusions. Haemocytic infiltrations were found in the surrounding connective tissues of all infected organs. However, these light infections are not causing morbidity and mortalityof the green mussel P.viridis. This study provides baseline information on health profile of the green mussel P.viridis. Further investigations are needed particularly on parasite species identification and their ecology. Understanding of the morphology and pathology of parasites infecting mollusks are very important for management of the resources.

  17. Molecular cloning of the heat shock protein 20 gene from Paphia textile and its expression in response to heat shock

    NASA Astrophysics Data System (ADS)

    Li, Jiakai; Wu, Xiangwei; Tan, Jing; Zhao, Ruixiang; Deng, Lingwei; Liu, Xiande

    2015-07-01

    P. textile is an important aquaculture species in China and is mainly distributed in Fujian, Guangdong, and Guangxi Provinces. In this study, an HSP20 cDNA designated PtHSP20 was cloned from P. textile. The full-length cDNA of PtHSP20 is 1 090 bp long and contains a 5' untranslated region (UTR) of 93 bp, a 3' UTR of 475 bp, and an open reading frame (ORF) of 522 bp. The PtHSP20 cDNA encodes 173 amino acid residues and has a molecular mass of 20.22 kDa and an isoelectric point of 6.2. Its predicted amino acid sequence shows that PtHSP20 contains a typical α-crystallin domain (residues 77-171) and three polyadenylation signal-sequences at the C-terminus. According to an amino acid sequence alignment, PtHSP20 shows moderate homology to other mollusk sHSPs. PtHSP20 mRNA was present in all of the test tissues including the heart, digestive gland, adductor muscle, gonad, gill, and mantle, with the highest concentration found in the gonad. Under the stress of high temperature, the expression of PtHSP20 mRNA was down-regulated in all of the tissues except the adductor muscle and gonad.

  18. Onabotulinum toxin A dosage trends over time for adductor spasmodic dysphonia: A 15-year experience.

    PubMed

    Tang, Christopher G; Novakovic, Daniel; Mor, Niv; Blitzer, Andrew

    2016-03-01

    Although onabotulinum neurotoxin A (BoNTA) has been used for over three decades for the treatment of adductor spasmodic dysphonia, no study has been performed to look at the trend of BoNTA dosages across time. The goal of this study is to evaluate the dosage trends to determine if the dosage necessary for voice improvement in patients increases over time. Charts were reviewed for patients with 15 years or more of experience. Linear regression analysis was performed to determine correlation coefficients and trends. Fifty-five patients receiving BoNTA injections by the senior author (a.b.) for over 15 years were evaluated. Thirty-nine patients (82% female) met inclusion criteria. Patients received injections over an average of 18.6 years ± 1.36 years, with the longest follow-up of 21.5 years. Of 39 patients, 16 (41%) had a negative correlation coefficient (Pearson's r) suggesting a decrease over time, whereas 23 (59%) had a positive correlation coefficient suggesting an increase over time. The mean correlation coefficient was 0.139 ± 0.534 and P < 0.05 in 19 patients and P > 0.05 in 20 patients. R(2) for all patients were less than 0.75. Onabotulinum neurotoxin A injection dosage trends vary depending on the individual over time. Overall, the dose range appears to be stable in the majority of patients, suggesting that tolerance does not play a significant part in dose variation over time. 4. Laryngoscope, 126:678-681, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  19. Bite Forces and Their Measurement in Dogs and Cats.

    PubMed

    Kim, Se Eun; Arzi, Boaz; Garcia, Tanya C; Verstraete, Frank J M

    2018-01-01

    Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs), and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA) of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull's morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

  20. The Palatal Interpterygoid Vacuities of Temnospondyls and the Implications for the Associated Eye- and Jaw Musculature.

    PubMed

    Witzmann, Florian; Werneburg, Ingmar

    2017-07-01

    A diagnostic feature of temnospondyls is the presence of an open palate with large interpterygoid vacuities, unlike the closed palate of most other early tetrapods, in which the vacuities are either slit-like or completely absent. Attachment sites on neurocranium and palatal bones in temnospondyls allow the reconstruction of a powerful m. retractor bulbi and a large, sheet-like m. levator bulbi that formed the elastic floor of the orbit. This muscle arrangement indicates that temnospondyls were able to retract the eyeballs through the interpterygoid vacuities into the buccal cavity, like extant frogs and salamanders. In contrast, attachment sites on palate and neurocranium suggest a rather sauropsid-like arrangement of these muscles in stem-tetrapods and stem-amniotes. However, the anteriorly enlarged, huge interpterygoid vacuities of long-snouted stereospondyls suggest that eye retraction was not the only function of the vacuities here, since the eye-muscles filled only the posterior part of the vacuities. We propose an association of the vacuities in temnospondyls with a long, preorbital part of the m. adductor mandibulae internus (AMIa). The trochlea-like, anterior edge of the adductor chamber suggests that a tendon of the AMIa was redirected in an anteromedial direction in the preorbital skull and dorsal to the pterygoids. This tendon then unfolded into a wide aponeurosis bearing the flattened AMIa that filled almost the complete interpterygoid vacuities anterior to the orbits. Our muscle reconstructions permit comprehensive insights to the comparative soft tissue anatomy of early tetrapods and provide the basis for a biomechanic analysis of biting performances in the future. Anat Rec, 300:1240-1269, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  1. Intermuscular relationship of human muscle fiber type proportions: slow leg muscles predict slow neck muscles.

    PubMed

    Vikne, Harald; Gundersen, Kristian; Liestøl, Knut; Maelen, Jan; Vøllestad, Nina

    2012-04-01

    Our aim in this study was to examine whether the muscle fiber type proportions in different muscles from the same individual are interrelated. Samples were excised from five skeletal muscles in each of 12 human autopsy cases, and the fiber type proportions were determined by immunohistochemistry. We further examined the intermuscular relationship in fiber type proportion by reanalyzing three previously published data sets involving other muscles. Subjects demonstrated a predominantly high or low proportion of type 1 fibers in all examined muscles, and the overall difference between individuals was statistically significant (P < 0.001). Accordingly, the type 1 fiber proportions in most muscles were positively correlated (median r = 0.42, range -0.03-0.80). Similar results were also obtained from the three reanalyzed data sets. We suggest the existence of an across-muscle phenotype with respect to fiber type proportions; some individuals display generally faster muscles and some individuals slower muscles when compared with others. Copyright © 2011 Wiley Periodicals, Inc.

  2. Different horse's paces during hippotherapy on spatio-temporal parameters of gait in children with bilateral spastic cerebral palsy: A feasibility study.

    PubMed

    Antunes, Fabiane Nunes; Pinho, Alexandre Severo do; Kleiner, Ana Francisca Rozin; Salazar, Ana Paula; Eltz, Giovana Duarte; de Oliveira Junior, Alcyr Alves; Cechetti, Fernanda; Galli, Manuela; Pagnussat, Aline Souza

    2016-12-01

    Hippotherapy is often carried out for the rehabilitation of children with Cerebral Palsy (CP), with the horse riding at a walking pace. This study aimed to explore the immediate effects of a hippotherapy protocol using a walk-trot pace on spatio-temporal gait parameters and muscle tone in children with Bilateral Spastic CP (BS-CP). Ten children diagnosed with BS-CP and 10 healthy aged-matched children (reference group) took part in this study. The children with BS-CP underwent two sessions of hippotherapy for one week of washout between them. Two protocols (lasting 30min) were applied on separate days: Protocol 1: the horse's pace was a walking pace; and Protocol 2: the horse's pace was a walk-trot pace. Children from the reference group were not subjected to treatment. A wireless inertial measurement unit measured gait spatio-temporal parameters before and after each session. The Modified Ashworth Scale was applied for muscle tone measurement of hip adductors. The participants underwent the gait assessment on a path with surface irregularities (ecological context). The comparisons between BS-CP and the reference group found differences in all spatio-temporal parameters, except for gait velocity. Within-group analysis of children with BS-CP showed that the swing phase did not change after the walk pace and after the walk-trot pace. The percentage of rolling phase and double support improved after the walk-trot. The spasticity of the hip adductors was significantly reduced as an immediate result of both protocols, but this decrease was more evident after the walk-trot. The walk-trot protocol is feasible and is able to induce an immediate effect that improves the gait spatio-temporal parameters and the hip adductors spasticity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. No effect of hypergravity on adult rat ventral horn neuron size or SDH activity

    NASA Technical Reports Server (NTRS)

    Roy, R. R.; Ishihara, A.; Moran, M. M.; Wade, C. E.; Edgerton, V. R.

    2001-01-01

    BACKGROUND: Spaceflights of short duration (approximately 2 wk) result in adaptations in the size and/or metabolic properties of a select population of motoneurons located in the lumbosacral region of the rat spinal cord. A decrease in succinate dehydrogenase (SDH, an oxidative marker enzyme) activity of moderately sized (500-800 microm2) motoneurons in the retrodorsolateral region of the spinal cord (L6) has been observed after a 14-d flight. HYPOTHESIS: Our hypothesis was that exposure to short-term hypergravity would result in adaptations in the opposite direction, reflecting a continuum of morphological and biochemical responses in the spinal motoneurons from zero gravity to hypergravity. METHODS: Young, male rats were centrifuged at either 1.5 or 2.0 G for 2 wk. The size and SDH activity of a population of motoneurons in the retrodorsolateral region of the spinal cord (L5) were determined and compared with age-matched rats maintained at 1.0 G. The absolute and relative (to body weight) masses of the soleus, gastrocnemius, adductor longus and tibialis anterior muscles were compared among the three groups. RESULTS: There were no effects of either hypergravity intervention on the motoneuron properties. Rats maintained under hypergravity conditions gained less body mass than rats kept at 1.0 G. For the 1.5 and 2.0 G groups, the muscle absolute mass was smaller and relative mass similar to that observed in the 1.0 G rats, except for the adductor longus. The adductor longus absolute mass was similar to and the relative mass larger in both hypergravity groups than in the 1.0 G group. CONCLUSIONS: Our hypothesis was rejected. The findings suggest that rat motoneurons are more responsive to short-term chronic exposure to spaceflight than to hypergravity conditions.

  4. Long-term voice handicap index after type II thyroplasty using titanium bridges for adductor spasmodic dysphonia.

    PubMed

    Sanuki, Tetsuji; Yumoto, Eiji; Kodama, Narihiro; Minoda, Ryosei; Kumai, Yoshihiko

    2014-06-01

    To determine the long-term functional outcomes of type II thyroplasty using titanium bridges for adductor spasmodic dysphonia (AdSD) by perceptual analysis using the Voice Handicap Index-10 (VHI-10) and by acoustic analysis. Fifteen patients with AdSD underwent type II thyroplasty using titanium brides between August 2006 and February 2011. VHI-10 scores, a patient-based survey that quantifies a patient's perception of his or her vocal handicap, were determined before and at least 2 years after surgery. Concurrent with the VHI-10 evaluation, acoustic parameters were assessed, including jitter, shimmer, harmonic-to-noise ratio (HNR), standard deviation of F0 (SDF0), and degree of voice breaks (DVB). The average follow-up interval was 30.1 months. No patient had strangulation of the voice, and all were satisfied with the voice postoperatively. In the perceptual analysis, the mean VHI-10 score improved significantly, from 26.7 to 4.1 two years after surgery. All patients had significantly improved each score of three different aspects of VHI-10, representing improved functional, physical, and emotional well-being. All acoustic parameters improved significantly 2 years after surgery. The treatment of AdSD with type II thyroplasty significantly improved the voice-related quality of life and acoustic parameters 2 years after surgery. The results of the study suggest that type II thyroplasty using titanium bridges provides long-term relief of vocal symptoms in patients with AdSD. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. Nerve-muscle interactions during flight muscle development in Drosophila

    NASA Technical Reports Server (NTRS)

    Fernandes, J. J.; Keshishian, H.

    1998-01-01

    During Drosophila pupal metamorphosis, the motoneurons and muscles differentiate synchronously, providing an opportunity for extensive intercellular regulation during synapse formation. We examined the existence of such interactions by developmentally delaying or permanently eliminating synaptic partners during the formation of indirect flight muscles. When we experimentally delayed muscle development, we found that although adult-specific primary motoneuron branching still occurred, the higher order (synaptic) branching was suspended until the delayed muscle fibers reached a favourable developmental state. In reciprocal experiments we found that denervation caused a decrease in the myoblast pool. Furthermore, the formation of certain muscle fibers (dorsoventral muscles) was specifically blocked. Exceptions were the adult muscles that use larval muscle fibers as myoblast fusion targets (dorsal longitudinal muscles). However, when these muscles were experimentally compelled to develop without their larval precursors, they showed an absolute dependence on the motoneurons for their formation. These data show that the size of the myoblast pool and early events in fiber formation depend on the presence of the nerve, and that, conversely, peripheral arbor development and synaptogenesis is closely synchronized with the developmental state of the muscle.

  6. Force encoding in muscle spindles during stretch of passive muscle

    PubMed Central

    Blum, Kyle P.; Zytnicki, Daniel

    2017-01-01

    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

  7. Force encoding in muscle spindles during stretch of passive muscle.

    PubMed

    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

  8. Painful unilateral temporalis muscle enlargement: reactive masticatory muscle hypertrophy.

    PubMed

    Katsetos, Christos D; Bianchi, Michael A; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2014-06-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptomatic improvement only after undergoing botulinum toxin injections. Muscle biopsy is key in the diagnosis of reactive masticatory muscle hypertrophy and its distinction from masticatory muscle myopathy (hypertrophic branchial myopathy) and other non-reactive causes of painful asymmetric temporalis muscle enlargement.

  9. Evaluation of muscle hyperactivity of the grimacing muscles by unilateral tight eyelid closure and stapedius muscle tone.

    PubMed

    Shiba, Masato; Matsuo, Kiyoshi; Ban, Ryokuya; Nagai, Fumio

    2012-10-01

    Muscle hyperactivity of grimacing muscles, including the orbicularis oculi and corrugator supercilii muscles that cause crow's feet and a glabellar frown line with ageing, cannot be accurately evaluated by surface observation. In 71 subjects, this study investigated the extent to which grimacing muscles are innervated by the bilateral motor cortices, whether the corticofacial projection to the grimacing muscles affects the facially innervated stapedius muscle tone by measuring static compliance of the tympanic membrane, and whether unilateral tight eyelid closure with contraction of the grimacing muscles changes static compliance. Unilateral tight eyelid closure and its subsequent change in the contralateral vertical medial eyebrow position revealed that motor neurons of the orbicularis oculi and corrugator supercilii muscles were innervated by the bilateral motor cortices with weak-to-strong contralateral dominance. The orbicularis oculi, corrugator supercilii, and stapedius muscles innervated by the bilateral motor cortices had increased muscle hyperactivity, which lowered the vertical medial eyebrow position and decreased the static compliance of the tympanic membrane more than those innervated by the unilateral motor cortex. Unilateral enhanced tight eyelid closure with contraction of the grimacing muscles in certain subjects ipsilaterally decreased the static compliance with increased contraction of the stapedius muscle, which probably occurs to immobilise the tympanic membrane and protect the inner ear from loud sound. Evaluation of unilateral tight eyelid closure and the subsequent change in the contralateral vertical medial eyebrow position as well as a measurement of the static compliance for the stapedius muscle tone has revealed muscle hyperactivity of grimacing muscles.

  10. The effects of surgical lengthening of hamstring muscles in children with cerebral palsy--the consequences of pre-operative muscle length measurement.

    PubMed

    Laracca, Ettore; Stewart, Caroline; Postans, Neil; Roberts, Andrew

    2014-03-01

    Children with cerebral palsy often undergo multiple orthopaedic surgical procedures in a single episode. Evidence of the effectiveness of individual components within the overall package is sparse. The introduction of musculoskeletal modelling in Oswestry has led to a more conservative management approach being taken with hamstring muscles for children walking in a degree of crouch. Muscles which were shown to be of at least normal length at initial contact were not surgically lengthened, as would have been the case previously. A retrospective review of 30 such patients was therefore possible, comparing 15 patients treated before the policy change who had their hamstrings lengthened with 15 treated after who did not. All patients had pre and post operative gait assessments and significant changes were observed for each group separately and for the two groups when compared. The comparison revealed that preserving the hamstrings does tend to reduce, and therefore normalize, the dynamic muscle length. Examination of the two patient groups separately, however, reveals a more complex picture with more global gait improvements seen when the hamstrings were lengthened. No absolute recommendation can be made to inform the clinical management of all children with normal to long hamstring muscles during gait. The final decision of whether to include a hamstring lengthening will need to take into account the characteristics of the individual child. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Age-related changes in rat intrinsic laryngeal muscles: analysis of muscle fibers, muscle fiber proteins, and subneural apparatuses.

    PubMed

    Nishida, Naoya; Taguchi, Aki; Motoyoshi, Kazumi; Hyodo, Masamitsu; Gyo, Kiyofumi; Desaki, Junzo

    2013-03-01

    We compared age-related changes in the intrinsic laryngeal muscles of aged and young adult rats by determining the number and diameter of muscle fibers, contractile muscle protein (myosin heavy chain isoforms, MHC) composition, and the morphology of the subneural apparatuses. In aged rats, both the numbers and the diameters of muscle fibers decreased in the cricothyroid (CT) muscle. The number of fibers, but not diameter, decreased in the thyroarytenoid (TA) muscle. In the posterior cricoarytenoid (PCA) muscle, neither the number nor the diameter of fibers changed significantly. Aging was associated with a decrease in type IIB and an increase in type IIA MHC isoform levels in CT muscle, but no such changes were observed in the TA or PCA muscles. Morphological examination of primary synaptic clefts of the subneural apparatus revealed that aging resulted in decreased labyrinthine and increased depression types in only the CT muscle. In the aged group, morphologically immature subneural apparatuses were found infrequently in the CT muscle, indicating continued tissue remodeling. We suggest, therefore, that age-related changes in the intrinsic laryngeal muscles primarily involve the CT muscle, whereas the structures of the TA and PCA muscles may better resist aging processes and therefore are less vulnerable to functional impairment. This may reflect differences in their roles; the CT muscle controls the tone of the vocal folds, while the TA and PCA muscles play an essential role in vital activities such as respiration and swallowing.

  12. Muscle force depends on the amount of transversal muscle loading.

    PubMed

    Siebert, Tobias; Till, Olaf; Stutzig, Norman; Günther, Michael; Blickhan, Reinhard

    2014-06-03

    Skeletal muscles are embedded in an environment of other muscles, connective tissue, and bones, which may transfer transversal forces to the muscle tissue, thereby compressing it. In a recent study we demonstrated that transversal loading of a muscle with 1.3Ncm(-2) reduces maximum isometric force (Fim) and rate of force development by approximately 5% and 25%, respectively. The aim of the present study was to examine the influence of increasing transversal muscle loading on contraction dynamics. Therefore, we performed isometric experiments on rat M. gastrocnemius medialis (n=9) without and with five different transversal loads corresponding to increasing pressures of 1.3Ncm(-2) to 5.3Ncm(-2) at the contact area between muscle and load. Muscle loading was induced by a custom-made plunger which was able to move in transversal direction. Increasing transversal muscle loading resulted in an almost linear decrease in muscle force from 4.8±1.8% to 12.8±2% Fim. Compared to an unloaded isometric contraction, rate of force development decreased from 20.2±4.0% at 1.3Ncm(-2) muscle loading to 34.6±5.7% at 5.3Ncm(-2). Experimental observation of the impact of transversal muscle loading on contraction dynamics may help to better understand muscle tissue properties. Moreover, applying transversal loads to muscles opens a window to analyze three-dimensional muscle force generation. Data presented in this study may be important to develop and validate muscle models which enable simulation of muscle contractions under compression and enlighten the mechanisms behind. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Composition of Muscle Fiber Types in Rat Rotator Cuff Muscles.

    PubMed

    Rui, Yongjun; Pan, Feng; Mi, Jingyi

    2016-10-01

    The rat is a suitable model to study human rotator cuff pathology owing to the similarities in morphological anatomy structure. However, few studies have reported the composition muscle fiber types of rotator cuff muscles in the rat. In this study, the myosin heavy chain (MyHC) isoforms were stained by immunofluorescence to show the muscle fiber types composition and distribution in rotator cuff muscles of the rat. It was found that rotator cuff muscles in the rat were of mixed fiber type composition. The majority of rotator cuff fibers labeled positively for MyHCII. Moreover, the rat rotator cuff muscles contained hybrid fibers. So, compared with human rotator cuff muscles composed partly of slow-twitch fibers, the majority of fast-twitch fibers in rat rotator cuff muscles should be considered when the rat model study focus on the pathological process of rotator cuff muscles after injury. Gaining greater insight into muscle fiber types in rotator cuff muscles of the rat may contribute to elucidate the mechanism of pathological change in rotator cuff muscles-related diseases. Anat Rec, 299:1397-1401, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. CYTOCHEMICAL LOCALIZATION OF TWO GLYCOLYTIC DEHYDROGENASES IN WHITE SKELETAL MUSCLE

    PubMed Central

    Fahimi, H. Dariush; Karnovsky, Morris J.

    1966-01-01

    The cytochemical localization, by conventional methods, of lactate and glyceraldehyde-3-phosphate dehydrogenases is limited, firstly, by the solubility of these enzymes in aqueous media and, secondly, by the dependence of the final electron flow from reduced nicotinamide-adenine dinucleotide (NADH) to the tetrazolium on tissue diaphorase activity: localization is therefore that of the diaphorase, which in rabbit adductor magnus is mitochondrial. NADH has been found to have great affinity to bind in the sarcoplasmic reticulum, and, therefore, if it is generated freely in the incubation media containing 2,2',5,5'-tetra-p-nitrophenyl-3,3'-(3,3'-dimethoxy-4,4'-phenylene)-ditetrazolium chloride (TNBT) and N-methyl phenazonium methyl sulfate (PMS), it can bind there and cause a false staining. Since such a production of NADH can readily occur in the incubation media for glycolytic dehydrogenases due to diffusion of these soluble enzymes from tissue sections, the prevention of enzyme solubilization is extremely important. Fixation in formaldehyde prevented such enzyme diffusion, while at the same time sufficient activity persisted to allow for adequate staining. The incubation media contained PMS, so that the staining system was largely independent of tissue diaphorase activity. Application of these methods to adductor magnus of rabbit revealed by light microscopy, for both enzymes, a fine network which was shown by electron microscopy to represent staining of the sarcoplasmic reticulum. Mitochondria also reacted. These findings add further support for the notion that the sarcoplasmic reticulum is probably involved in glycolytic activity. PMID:4288329

  15. Muscle Bioenergetic Considerations for Intrinsic Laryngeal Skeletal Muscle Physiology

    ERIC Educational Resources Information Center

    Sandage, Mary J.; Smith, Audrey G.

    2017-01-01

    Purpose: Intrinsic laryngeal skeletal muscle bioenergetics, the means by which muscles produce fuel for muscle metabolism, is an understudied aspect of laryngeal physiology with direct implications for voice habilitation and rehabilitation. The purpose of this review is to describe bioenergetic pathways identified in limb skeletal muscle and…

  16. Human Muscle Fiber

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The stimulus of gravity affects RNA production, which helps maintain the strength of human muscles on Earth (top), as seen in this section of muscle fiber taken from an astronaut before spaceflight. Astronauts in orbit and patients on Earth fighting muscle-wasting diseases need countermeasures to prevent muscle atrophy, indicated here with white lipid droplets (bottom) in the muscle sample taken from the same astronaut after spaceflight. Kerneth Baldwin of the University of California, Irvine, is conducting research on how reducing the stimulus of gravity affects production of the RNA that the body uses as a blueprint for making muscle proteins. Muscle proteins are what give muscles their strength, so when the RNA blueprints aren't available for producing new proteins to replace old ones -- a situation that occurs in microgravity -- the muscles atrophy. When the skeletal muscle system is exposed to microgravity during spaceflight, the muscles undergo a reduced mass that translates to a reduction in strength. When this happens, muscle endurance decreases and the muscles are more prone to injury, so individuals could have problems in performing extravehicular activity [space walks] or emergency egress because their bodies are functionally compromised.

  17. Strength, Endurance, Throwing Velocity and in-Water Jump Performance of Elite German Water Polo Players

    PubMed Central

    Zinner, Christoph; Sperlich, Billy; Krueger, Malte; Focke, Tim; Reed, Jennifer; Mester, Joachim

    2015-01-01

    The purpose of this study was threefold: 1) to assess the eggbeater kick and throwing performance using a number of water polo specific tests, 2) to explore the relation between the eggbeater kick and throwing performance, and 3) to investigate the relation between the eggbeater kick in the water and strength tests performed in a controlled laboratory setting in elite water polo players. Fifteen male water polo players of the German National Team completed dynamic and isometric strength tests for muscle groups (adductor, abductor, abdominal, pectoralis) frequently used during water polo. After these laboratory strength tests, six water polo specific in-water tests were conducted. The eggbeater kick assessed leg endurance and agility, maximal throwing velocity and jump height. A 400 m test and a sprint test examined aerobic and anaerobic performance. The strongest correlation was found between jump height and arm length (p < 0.001, r = 0.89). The laboratory diagnostics of important muscles showed positive correlations with the results of the in-water tests (p < 0.05, r = 0.52–0.70). Muscular strength of the adductor, abdominal and pectoralis muscles was positively related to in-water endurance agility as assessed by the eggbeater kick (p < 0.05; r = 0.53–0.66). Findings from the current study emphasize the need to assess indices of water polo performance both in and out of the water as well as the relation among these parameters to best assess the complex profile of water polo players. PMID:25964818

  18. Training Effectiveness of The Inertial Training and Measurement System

    PubMed Central

    Naczk, Mariusz; Brzenczek-Owczarzak, Wioletta; Arlet, Jarosław; Naczk, Alicja; Adach, Zdzisław

    2014-01-01

    The purpose of this study was to evaluate the efficacy of inertial training with different external loads using a new original device - the Inertial Training and Measurement System (ITMS). Forty-six physical education male students were tested. The participants were randomly divided into three training groups and a control group (C group). The training groups performed inertial training with three different loads three times weekly for four weeks. The T0 group used only the mass of the ITMS flywheel (19.4 kg), the T5 and T10 groups had an additional 5 and 10 kg on the flywheel, respectively. Each training session included three exercise sets involving the shoulder joint adductors. Before and after training, the maximal torque and power were measured on an isokinetic dynamometer during adduction of the shoulder joint. Simultaneously, the electromyography activity of the pectoralis major muscle was recorded. Results of the study indicate that ITMS training induced a significant increase in maximal muscle torque in the T0, T5, T10 groups (15.5%, 13.0%, and 14.0%, respectively). Moreover, ITMS training caused a significant increase in power in the T0, T5, T10 groups (16.6%, 19.5%, and 14.5%, respectively). The percentage changes in torque and power did not significantly differ between training groups. Electromyography activity of the pectoralis major muscle increased only in the T0 group after four weeks of training. Using the ITMS device in specific workouts allowed for an increase of shoulder joint adductors torque and power in physical education students. PMID:25713662

  19. Trunk extensor muscle fatigue influences trunk muscle activities.

    PubMed

    Hoseinpoor, Tahere Seyed; Kahrizi, Sedighe; Mobini, Bahram

    2015-01-01

    Trunk muscles fatigue is one of the risk factors in workplaces and daily activities. Loads would be redistributed among active and passive tissues in a non-optimal manner in fatigue conditions. Therefore, a single tissue might be overloaded with minimal loads and as a result the risk of injury would increase. The goal of this paper was to assess the electromyographic response of trunk extensor and abdominal muscles after trunk extensor muscles fatigue induced by cyclic lifting task. This was an experimental study that twenty healthy women participated. For assessing automatic response of trunk extensor and abdominal muscles before and after the fatigue task, electromyographic activities of 6 muscles: thorasic erector spine (TES), lumbar erector spine (LES), lumbar multifidus (LMF), transverse abdominis/ internal oblique (TrA/IO), rectus abdominis (RA) and external oblique (EO) were recorded in standing position with no load and symmetric axial loads equal to 25% of their body weights. Statistical analysis showed that all the abdominal muscles activity decreased with axial loads after performing fatigue task but trunk extensor activity remained constant. Results of the current study indicated that muscle recruitment strategies changed with muscle fatigue and load bearing, therefore risks of tissue injury may increase in fatigue conditions.

  20. Combined adductor canal block with periarticular infiltration versus periarticular infiltration for analgesia after total knee arthroplasty.

    PubMed

    Ma, Jinhui; Gao, Fuqiang; Sun, Wei; Guo, Wanshou; Li, Zirong; Wang, Weiguo

    2016-12-01

    Both adductor canal block (ACB) and periarticular infiltration (PI) have been shown to reduce pain after total knee arthroplasty (TKA) without the motor blockade. However, the efficacy and safety of combined ACB with PI (ACB + PI) as compared to PI alone for analgesia after TKA remains controversial. We therefore performed a meta-analysis to compare the effects of ACB + PI with PI alone on pain controll after TKA. PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched to identify studies comparing ACB + PI with PI alone for TKA patients. The primary outcomes included pain score with rest or activity and morphine consumption. Secondary outcomes were distance walked, length of hospital stay, and postoperative complications. Relevant data were analyzed using RevMan v5.3. Three studies involving 337 patients were included. Combined ACB with PI was associated with longer distances walked than PI alone (MD = 7.27, 95% CI: 0.43-14.12, P = 0.04) on postoperative day 1. The outcomes of pain, morphine consumption, length of hospital stay, and postoperative complications were not statistically different between the 2 groups (P > 0.05). Our meta-analysis suggests that combined ACB with PI may achieve earlier ambulation for patients after TKA without a reduction in analgesia when compared to PI alone in the early postoperative period. There were no significant differences in morphine consumption, length of hospital stay, and postoperative complications between the 2 groups. However, owing to the variation of included studies, no firm conclusions can be drawn.

  1. The Comparison of Thyroarytenoid Muscle Myectomy and Type II Thyroplasty for Spasmodic Dysphonia.

    PubMed

    Nomoto, Masaki; Tokashiki, Ryoji; Hiramatsu, Hiroyuki; Konomi, Ujimoto; Motohashi, Rei; Sakurai, Eriko; Toyomura, Fumimasa; Ueda, Yuri; Inoue, Shun; Tsukahara, Kiyoaki; Suzuki, Mamoru

    2015-07-01

    Surgical treatments for adductor spasmodic dysphonia include bilateral thyroarytenoid muscle myectomy (TAM) and type II thyroplasty (TPII), both of which are commonly performed. The present study aimed to compare the effects of TAM and TPII. Retrospective study. Subjects were 30 and 35 patients who underwent TAM and TPII, between March 2008 and November 2012. Voice quality was evaluated based on "voice handicap index 10 (VHI10)" and auditory impressions before and 6 months after surgery using five parameters: "strangulation," "interruption," "tremor," "grade," and "breathiness." Comparison of the two procedures revealed significant improvements in VHI10, strangulation, interruption, and tremor, and a significant decline in breathiness after surgery. In particular, VHI10 was improved by more than six points in 90% of patients with TAM, and 96% with TPII. No significant difference was observed between the severities of two procedures preoperatively. Comparison of each postoperative score between the two procedures revealed that TAM significantly improved strangulation, interruption, and tremor, and significantly worsened breathiness, with no significant difference in VHI10. Scatter plots (x: preoperative scores; y: postoperative scores) and regression lines of evaluation items demonstrated that TAM is more effective than TPII in severe cases. Compared with TPII, TAM tends to improve strangulation, interruption, and tremor; however, it tends to worsen breathiness postoperatively. Postoperative VHI10 scores did not differ significantly between the two procedures. Given favorable improvement rates, both surgical procedures were considered effective. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  2. Individual muscle control using an exoskeleton robot for muscle function testing.

    PubMed

    Ueda, Jun; Ming, Ding; Krishnamoorthy, Vijaya; Shinohara, Minoru; Ogasawara, Tsukasa

    2010-08-01

    Healthy individuals modulate muscle activation patterns according to their intended movement and external environment. Persons with neurological disorders (e.g., stroke and spinal cord injury), however, have problems in movement control due primarily to their inability to modulate their muscle activation pattern in an appropriate manner. A functionality test at the level of individual muscles that investigates the activity of a muscle of interest on various motor tasks may enable muscle-level force grading. To date there is no extant work that focuses on the application of exoskeleton robots to induce specific muscle activation in a systematic manner. This paper proposes a new method, named "individual muscle-force control" using a wearable robot (an exoskeleton robot, or a power-assisting device) to obtain a wider variety of muscle activity data than standard motor tasks, e.g., pushing a handle by hand. A computational algorithm systematically computes control commands to a wearable robot so that a desired muscle activation pattern for target muscle forces is induced. It also computes an adequate amount and direction of a force that a subject needs to exert against a handle by his/her hand. This individual muscle control method enables users (e.g., therapists) to efficiently conduct neuromuscular function tests on target muscles by arbitrarily inducing muscle activation patterns. This paper presents a basic concept, mathematical formulation, and solution of the individual muscle-force control and its implementation to a muscle control system with an exoskeleton-type robot for upper extremity. Simulation and experimental results in healthy individuals justify the use of an exoskeleton robot for future muscle function testing in terms of the variety of muscle activity data.

  3. Muscle Contraction.

    PubMed

    Sweeney, H Lee; Hammers, David W

    2018-02-01

    SUMMARYMuscle cells are designed to generate force and movement. There are three types of mammalian muscles-skeletal, cardiac, and smooth. Skeletal muscles are attached to bones and move them relative to each other. Cardiac muscle comprises the heart, which pumps blood through the vasculature. Skeletal and cardiac muscles are known as striated muscles, because the filaments of actin and myosin that power their contraction are organized into repeating arrays, called sarcomeres, that have a striated microscopic appearance. Smooth muscle does not contain sarcomeres but uses the contraction of filaments of actin and myosin to constrict blood vessels and move the contents of hollow organs in the body. Here, we review the principal molecular organization of the three types of muscle and their contractile regulation through signaling mechanisms and discuss their major structural and functional similarities that hint at the possible evolutionary relationships between the cell types. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  4. The effects of unilateral and bilateral eccentric overload training on hypertrophy, muscle power and COD performance, and its determinants, in team sport players.

    PubMed

    Núñez, Francisco Javier; Santalla, Alfredo; Carrasquila, Irene; Asian, Jose Antonio; Reina, Jose Ignacio; Suarez-Arrones, Luis Jesús

    2018-01-01

    The study aimed to compare the chronic eccentric-overload training effects of unilateral (lateral lunge) vs bilateral (half-squat) using an inertial device, on hypertrophy and physical performance. Twenty-seven young team sports male players performed a 4 sets of 7 repetitions of inertial eccentric overload training, biweekly for 6 weeks, distributed in unilateral lunge group (UG: age: 22.8 ± 2.9 years; body mass: 75.3 ± 8.8 kg; height: 177.3 ± 3.7 cm) and bilateral squat group (BG: age: 22.6 ± 2.7 years; body mass: 79.5 ± 12.8 kg; height: 164.2 ± 7 cm). Lower limb muscle volume, counter movement jump (CMJ), power with both (POWER), dominant (POWERd) and no-dominant leg (POWERnd), change of direction turn of 90° with dominant (COD90d) and no-dominant leg (COD90nd) and 180° (COD180d and COD180nd), and 10m sprint time (T-10m) were measured pre and post-intervention. The UG obtained an increase of adductor major (+11.1%) and vastus medialis (+12.6%) higher than BG. The BG obtained an increase of vastus lateralis (+9.9%) and lateral gastrocnemius (+9.1%) higher than UG. Both groups improved CMJ, POWER, POWERd, POWERnd, COD90 and DEC-COD90, without changes in T-10m. The UG decrease DEC-COD90nd (-21.1%) and BG increase POWER (+38.6%) substantially more than the other group. Six-weeks of unilateral / bilateral EO training induce substantial improvements in lower limbs muscle volume and functional performance, although unilateral training seems to be more effective in improving COD90 performance.

  5. The effects of unilateral and bilateral eccentric overload training on hypertrophy, muscle power and COD performance, and its determinants, in team sport players

    PubMed Central

    Carrasquila, Irene; Asian, Jose Antonio; Reina, Jose Ignacio

    2018-01-01

    The study aimed to compare the chronic eccentric-overload training effects of unilateral (lateral lunge) vs bilateral (half-squat) using an inertial device, on hypertrophy and physical performance. Twenty-seven young team sports male players performed a 4 sets of 7 repetitions of inertial eccentric overload training, biweekly for 6 weeks, distributed in unilateral lunge group (UG: age: 22.8 ± 2.9 years; body mass: 75.3 ± 8.8 kg; height: 177.3 ± 3.7 cm) and bilateral squat group (BG: age: 22.6 ± 2.7 years; body mass: 79.5 ± 12.8 kg; height: 164.2 ± 7 cm). Lower limb muscle volume, counter movement jump (CMJ), power with both (POWER), dominant (POWERd) and no-dominant leg (POWERnd), change of direction turn of 90° with dominant (COD90d) and no-dominant leg (COD90nd) and 180° (COD180d and COD180nd), and 10m sprint time (T-10m) were measured pre and post-intervention. The UG obtained an increase of adductor major (+11.1%) and vastus medialis (+12.6%) higher than BG. The BG obtained an increase of vastus lateralis (+9.9%) and lateral gastrocnemius (+9.1%) higher than UG. Both groups improved CMJ, POWER, POWERd, POWERnd, COD90 and DEC-COD90, without changes in T-10m. The UG decrease DEC-COD90nd (-21.1%) and BG increase POWER (+38.6%) substantially more than the other group. Six-weeks of unilateral / bilateral EO training induce substantial improvements in lower limbs muscle volume and functional performance, although unilateral training seems to be more effective in improving COD90 performance. PMID:29590139

  6. Scapular kinematic and shoulder muscle activity alterations after serratus anterior muscle fatigue.

    PubMed

    Umehara, Jun; Kusano, Ken; Nakamura, Masatoshi; Morishita, Katsuyuki; Nishishita, Satoru; Tanaka, Hiroki; Shimizu, Itsuroh; Ichihashi, Noriaki

    2018-02-23

    Although the serratus anterior muscle has an important role in scapular movement, no study to date has investigated the effect of serratus anterior fatigue on scapular kinematics and shoulder muscle activity. The purpose of this study was to clarify the effect of serratus anterior fatigue on scapular movement and shoulder muscle activity. The study participants were 16 healthy men. Electrical muscle stimulation was used to fatigue the serratus anterior muscle. Shoulder muscle strength and endurance, scapular movement, and muscle activity were measured before and after the fatigue task. The muscle activity of the serratus anterior, upper and lower trapezius, anterior and middle deltoid, and infraspinatus muscles was recorded, and the median power frequency of these muscles was calculated to examine the degree of muscle fatigue. The muscle endurance and median power frequency of the serratus anterior muscle decreased after the fatigue tasks, whereas the muscle activities of the serratus anterior, upper trapezius, and infraspinatus muscles increased. External rotation of the scapula at the shoulder elevated position increased after the fatigue task. Selective serratus anterior fatigue due to electric muscle stimulation decreased the serratus anterior endurance at the flexed shoulder position. Furthermore, the muscle activities of the serratus anterior, upper trapezius, and infraspinatus increased and the scapular external rotation was greater after serratus anterior fatigue. These results suggest that the rotator cuff and scapular muscle compensated to avoid the increase in internal rotation of the scapula caused by the dysfunction of the serratus anterior muscle. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  7. Clinics in diagnostic imaging (179). Severe rhabdomyolysis complicated by myonecrosis.

    PubMed

    Kok, Shi Xian Shawn; Tan, Tien Jin

    2017-08-01

    A 32-year-old man presented to the emergency department with severe right lower limb pain and swelling of three days' duration. He had multiple prior admissions for recurrent seizures and suicide attempts. Markedly elevated serum creatine kinase levels and urine myoglobinuria were consistent with a diagnosis of rhabdomyolysis. Initial magnetic resonance imaging of the right lower limb revealed diffuse muscle oedema and features of myositis in the gluteal muscles and the adductor, anterior and posterior compartments of the thigh. Follow-up magnetic resonance imaging performed 11 days later showed interval development of areas of myonecrosis and haemorrhage. The causes, clinical presentation and imaging features of rhabdomyolysis are discussed. Copyright: © Singapore Medical Association.

  8. Monitoring respiratory muscles.

    PubMed

    Nava, S

    1998-12-01

    The respiratory system consists of two main parts, the lung and the ventilatory pump. The latter consists of the bony structure of the thorax, the central respiratory controllers, the inspiratory and expiratory muscles, and the nerves innervating these muscles. Respiratory muscle fatigue occurs when respiratory muscle endurance is exceeded. Muscle fatigue is defined as a condition in which there is a reduction in the capacity for developing force and/or velocity of a muscle, resulting from muscle activity, and which is reversible by rest. The respiratory muscles are somewhat difficult to assess and the techniques employed are still relatively primitive. The most important methods of respiratory muscles function assessment are: 1) the vital capacity manoeuvre, which depends on maximum inspiratory and expiratory effort by the muscles and may be a useful indicator of respiratory muscle function; 2) radiological screening has been proposed for the detection of diaphragm paralysis. This may be helpful if the paralysis is unilateral, but bilateral paralysis is difficult to detect; and 3) respiratory muscles strength may be assessed with either voluntary or nonvoluntary manoeuvres. The function of the inspiratory muscles is assessed with 3 voluntary dependent manoeuvres. They are the so called Müller manoeuvre (or maximal inspiratory pressure), the sniff test and the combined test. All these three manoeuvres generate a pressure that is a reflection of complex interactions between several muscle groups since the efforts produce different mechanisms of activity of inspiratory and expiratory muscles. Two techniques are presently employed to assess diaphragm function, not being dependent on the patient's motivation: electrical phrenic nerve stimulation and cervical magnetic stimulation. Since it is less painful, magnetic cervical stimulation overcomes some of the difficulties encountered during electrical stimulation. With these two techniques recordings of diaphragmatic

  9. Ontogeny of the cranial system in Laonastes aenigmamus

    PubMed Central

    Herrel, Anthony; Fabre, Anne-Claire; Hugot, Jean-Pierre; Keovichit, Kham; Adriaens, Dominique; Brabant, Loes; Van Hoorebeke, Luc; Cornette, Raphael

    2012-01-01

    Rodents, together with bats, are among the ecologically most diverse and most speciose groups of mammals. Moreover, rodents show elaborate specializations of the feeding apparatus in response to the predominantly fore-aft movements of the lower jaw. The Laotian rock rat Laonastes aenigmamus was recently discovered and originally thought to belong to a new family. The difficulties in classifying L. aenigmamus based on morphological characters stem from the fact that it presents a mixture of sciurognathous and hystricognathous characteristics, including the morphology of the jaw adductors. The origin of the unusual muscular organization in this species remains, however, unclear. Here, we investigate the development of the masticatory system in Laonastes to better understand the origin of its derived morphology relative to other rodents. Our analyses show that skull and mandible development is characterized by an overall elongation of the snout region. Muscle mass increases with positive allometry during development and growth, and so does the force-generating capacity of the jaw adductor muscles (i.e. physiological cross-sectional area). Whereas fetal crania and musculature are more similar to those of typical rodents, adults diverge in the elongation of the rostral part of the skull and the disproportionate development of the zygomaticomandibularis. Our data suggest a functional signal in the development of the unusual cranial morphology, possibly associated with the folivorous trophic ecology of the species. PMID:22607030

  10. Variation in the cranium shape of wall lizards (Podarcis spp.): effects of phylogenetic constraints, allometric constraints and ecology.

    PubMed

    Urošević, Aleksandar; Ljubisavljević, Katarina; Jelić, Dušan; Ivanović, Ana

    2012-08-01

    We used geometric morphometrics to explore the influence of phylogenetic and allometric constraints as well as ecology on variation in cranium shape in five species of monophyletic, morphologically similar Podarcis lizards (Podarcis erhardii, Podarcis melisellensis, Podarcis muralis, Podarcis sicula and Podarcis taurica). These species belong to different clades, they differ in their habitat preferences and can be classified into two distinct morphotypes: saxicolous and terrestrial. We found (i) no phylogenetic signal in cranium shape, (ii) diverging allometric slopes among species, and (iii) a significant effect of habitat on cranium shape. The saxicolous species (P. erhardii and P. muralis) had crania with elongated parietals, elongated cranium bases, shortened anterior parts of the dorsal cranium, reduced chambers of the jaw adductor muscles and larger subocular foramina. These cranial features are adaptations that compensate for a flattened cranium, dwelling on vertical surfaces and seeking refuge in crevices. The crania of the terrestrial species (P. melisellensis, P. sicula and P. taurica) tended to be more elongate and robust, with enlarged chambers of the jaw adductor muscle, reduced skull bases and shortened parietals. Terrestrial species exhibited more variation in cranium shape than saxicolous species. Our study suggests that shape variation in Podarcis sp. lizards is largely influenced by ecology, which likely affects species-specific patterns of static allometry. Copyright © 2012 Elsevier GmbH. All rights reserved.

  11. Involuntary expiratory phonation as a dose-related consequence of L-dopa therapy in a patient with Parkinson's disease.

    PubMed

    Ishii, Kosuke; Kumada, Masanobu; Ueki, Akira; Yamamoto, Masanori; Hirose, Hajime

    2003-12-01

    We report a case of involuntary phonation caused by abnormal vocal cord movements during expiration in a patient with Parkinson's disease. A 60-year-old woman had been treated for parkinsonism at the outpatient clinic of the Department of Neurology since August 1999. She began to groan involuntarily in the daytime in September 2001. She could not eat well while groaning. Stridor was not noted during sleep at night. Endoscopic examination of the larynx revealed insufficient abduction of the bilateral vocal cords, although the glottis was not so small as to cause stridor during inspiration. During expiration, however, the vocal cords adducted, resulting in the involuntary production of voice. Electromyography showed an increase in the activity of the thyroarytenoid and lateral cricoarytenoid muscles. This muscle activity was further enhanced during inspiration. The involuntary phonation disappeared when the patient's dose of L-dopa was decreased, although she had a decrease in her systemic mobility as well. When the dose of L-dopa was increased to the therapeutic level, involuntary phonation recurred, and her voluntary systemic activity improved. In the present case, it was considered that excessive dopaminergic denervation occurred in the nerve innervating the laryngeal adductors. Involuntary voice appeared to be produced by hypertonus of the laryngeal adductors because of a lowering in the threshold level for L-dopa, even though the drug was administered at the usual dose.

  12. Relationships between eccentric hip isokinetic torque and functional performance.

    PubMed

    Baldon, Rodrigo de Marche; Lobato D, Ferreira Moreira; Carvalho, Lívia Pinheiro; Wun P, Yan Lam; Presotti, Cátia Valéria; Serrão, Fábio Viadanna

    2012-02-01

    Recently, attention in sports has been given to eccentric hip-muscle function, both in preventing musculoskeletal injuries and improving performance. To determine the key isokinetic variables of eccentric hip torque that predict the functional performance of women in the single-leg triple long jump (TLJ) and the timed 6-m single-leg hop (TH). Within-subject correlational study. Musculoskeletal laboratory. 32 healthy women age 18-25 y. The participants performed 2 sets of 5 eccentric hip-abductor/adductor and lateral/medial-rotator isokinetic contractions (30°/s) and 3 attempts in the TLJ and TH. The independent variables were the eccentric hip-abductor and -adductor and medial- and lateral-rotator isokinetic peak torque, normalized according to body mass (Nm/kg). The dependent variables were the longest distance achieved in the TLJ normalized according to body height and the shortest time spent during the execution of the TH. The forward-stepwise-regression analysis showed that the combination of the eccentric hip lateral-rotator and -abductor isokinetic peak torque provided the most efficient estimate of both functional tests, explaining 65% of the TLJ variance (P < .001) and 55% of the TH variance (P < .001). Higher values for eccentric hip lateral-rotator and hip-abductor torques reflected better performance. Thus, the eccentric action of these muscles should be considered in the development of physical training programs that aim to increase functional performance.

  13. Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex.

    PubMed

    Werneburg, Ingmar

    2015-01-01

    The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

  14. Activation of respiratory muscles during respiratory muscle training.

    PubMed

    Walterspacher, Stephan; Pietsch, Fabian; Walker, David Johannes; Röcker, Kai; Kabitz, Hans-Joachim

    2018-01-01

    It is unknown which respiratory muscles are mainly activated by respiratory muscle training. This study evaluated Inspiratory Pressure Threshold Loading (IPTL), Inspiratory Flow Resistive Loading (IFRL) and Voluntary Isocapnic Hyperpnea (VIH) with regard to electromyographic (EMG) activation of the sternocleidomastoid muscle (SCM), parasternal muscles (PARA) and the diaphragm (DIA) in randomized order. Surface EMG were analyzed at the end of each training session and normalized using the peak EMG recorded during maximum inspiratory maneuvers (Sniff nasal pressure: SnPna, maximal inspiratory mouth occlusion pressure: PImax). 41 healthy participants were included. Maximal activation was achieved for SCM by SnPna; the PImax activated predominantly PARA and DIA. Activations of SCM and PARA were higher in IPTL and VIH than for IFRL (p<0.05). DIA was higher applying IPTL compared to IFRL or VIH (p<0.05). IPTL, IFRL and VIH differ in activation of inspiratory respiratory muscles. Whereas all methods mainly stimulate accessory respiratory muscles, diaphragm activation was predominant in IPTL. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Muscle cooling delays activation of the muscle metaboreflex in humans.

    PubMed

    Ray, C A; Hume, K M; Gracey, K H; Mahoney, E T

    1997-11-01

    Elevation of muscle temperature has been shown to increase muscle sympathetic nerve activity (MSNA) during isometric exercise in humans. The purpose of the present study was to evaluate the effect of muscle cooling on MSNA responses during exercise. Eight subjects performed ischemic isometric handgrip at 30% of maximal voluntary contraction to fatigue followed by 2 min of postexercise muscle ischemia (PEMI), with and without local cooling of the forearm. Local cooling of the forearm decreased forearm muscle temperature from 31.8 +/- 0.4 to 23.1 +/- 0.8 degrees C (P = 0.001). Time to fatigue was not different during the control and cold trials (156 +/- 11 and 154 +/- 5 s, respectively). Arterial pressures and heart rate were not significantly affected by muscle cooling during exercise, although heart rate tended to be higher during the second minute of exercise (P = 0.053) during muscle cooling. Exercise-induced increases in MSNA were delayed during handgrip with local cooling compared with control. However, MSNA responses at fatigue and PEMI were not different between the two conditions. These findings suggest that muscle cooling delayed the activation of the muscle metaboreflex during ischemic isometric exercise but did not prevent its full expression during fatiguing contraction. These results support the concept that muscle temperature can play a role in the regulation of MSNA during exercise.

  16. Associations of passive muscle stiffness, muscle stretch tolerance, and muscle slack angle with range of motion: individual and sex differences.

    PubMed

    Miyamoto, Naokazu; Hirata, Kosuke; Miyamoto-Mikami, Eri; Yasuda, Osamu; Kanehisa, Hiroaki

    2018-05-29

    Joint range of motion (ROM) is an important parameter for athletic performance and muscular injury risk. Nonetheless, a complete description of muscular factors influencing ROM among individuals and between men and women is lacking. We examined whether passive muscle stiffness (evaluated by angle-specific muscle shear modulus), tolerance to muscle stretch (evaluated by muscle shear modulus at end-ROM), and muscle slack angle of the triceps surae are associated with the individual variability and sex difference in dorsiflexion ROM, using ultrasound shear wave elastography. For men, ROM was negatively correlated to passive muscle stiffness of the medial and lateral gastrocnemius in a tensioned state and positively to tolerance to muscle stretch in the medial gastrocnemius. For women, ROM was only positively correlated to tolerance to muscle stretch in all muscles but not correlated to passive muscle stiffness. Muscle slack angle was not correlated to ROM in men and women. Significant sex differences were observed only for dorsiflexion ROM and passive muscle stiffness in a tensioned state. These findings suggest that muscular factors associated with ROM are different between men and women. Furthermore, the sex difference in dorsiflexion ROM might be attributed partly to that in passive muscle stiffness of plantar flexors.

  17. The muscle spindle as a feedback element in muscle control

    NASA Technical Reports Server (NTRS)

    Andrews, L. T.; Iannone, A. M.; Ewing, D. J.

    1973-01-01

    The muscle spindle, the feedback element in the myotatic (stretch) reflex, is a major contributor to muscular control. Therefore, an accurate description of behavior of the muscle spindle during active contraction of the muscle, as well as during passive stretch, is essential to the understanding of muscle control. Animal experiments were performed in order to obtain the data necessary to model the muscle spindle. Spectral density functions were used to identify a linear approximation of the two types of nerve endings from the spindle. A model reference adaptive control system was used on a hybrid computer to optimize the anatomically defined lumped parameter estimate of the spindle. The derived nonlinear model accurately predicts the behavior of the muscle spindle both during active discharge and during its silent period. This model is used to determine the mechanism employed to control muscle movement.

  18. Tropomyosin 4 defines novel filaments in skeletal muscle associated with muscle remodelling/regeneration in normal and diseased muscle.

    PubMed

    Vlahovich, Nicole; Schevzov, Galina; Nair-Shaliker, Visalini; Ilkovski, Biljana; Artap, Stanley T; Joya, Josephine E; Kee, Anthony J; North, Kathryn N; Gunning, Peter W; Hardeman, Edna C

    2008-01-01

    The organisation of structural proteins in muscle into highly ordered sarcomeres occurs during development, regeneration and focal repair of skeletal muscle fibers. The involvement of cytoskeletal proteins in this process has been documented, with nonmuscle gamma-actin found to play a role in sarcomere assembly during muscle differentiation and also shown to be up-regulated in dystrophic muscles which undergo regeneration and repair [Lloyd et al.,2004; Hanft et al.,2006]. Here, we show that a cytoskeletal tropomyosin (Tm), Tm4, defines actin filaments in two novel compartments in muscle fibers: a Z-line associated cytoskeleton (Z-LAC), similar to a structure we have reported previously [Kee et al.,2004], and longitudinal filaments that are orientated parallel to the sarcomeric apparatus, present during myofiber growth and repair/regeneration. Tm4 is upregulated in paradigms of muscle repair including induced regeneration and focal repair and in muscle diseases with repair/regeneration features, muscular dystrophy and nemaline myopathy. Longitudinal Tm4-defined filaments also are present in diseased muscle. Transition of the Tm4-defined filaments from a longitudinal to a Z-LAC orientation is observed during the course of muscle regeneration. This Tm4-defined cytoskeleton is a marker of growth and repair/regeneration in response to injury, disease state and stress in skeletal muscle.

  19. Synchronous monitoring of muscle dynamics and muscle force for maximum isometric tetanus

    NASA Astrophysics Data System (ADS)

    Zakir Hossain, M.; Grill, Wolfgang

    2010-03-01

    Skeletal muscle is a classic example of a biological soft matter . At both macro and microscopic levels, skeletal muscle is exquisitely oriented for force generation and movement. In addition to the dynamics of contracting and relaxing muscle which can be monitored with ultrasound, variations in the muscle force are also expected to be monitored. To observe such force and sideways expansion variations synchronously for the skeletal muscle a novel detection scheme has been developed. As already introduced for the detection of sideways expansion variations of the muscle, ultrasonic transducers are mounted sideways on opposing positions of the monitored muscle. To detect variations of the muscle force, angle of pull of the monitored muscle has been restricted by the mechanical pull of the sonic force sensor. Under this condition, any variation in the time-of-flight (TOF) of the transmitted ultrasonic signals can be introduced by the variation of the path length between the transducers. The observed variations of the TOF are compared to the signals obtained by ultrasound monitoring for the muscle dynamics. The general behavior of the muscle dynamics and muscle force shows almost an identical concept. Since muscle force also relates the psychological boosting-up effects, the influence of boosting-up on muscle force and muscle dynamics can also be quantified form this study. Length-tension or force-length and force-velocity relationship can also be derived quantitatively with such monitoring.

  20. Test-retest reliability of cardinal plane isokinetic hip torque and EMG.

    PubMed

    Claiborne, Tina L; Timmons, Mark K; Pincivero, Danny M

    2009-10-01

    The objective of the present study was to establish test-retest reliability of isokinetic hip torque and prime mover electromyogram (EMG) through the three cardinal planes of motion. Thirteen healthy young adults participated in two experimental sessions, separated by approximately one week. During each session, isokinetic hip torque was evaluated on the Biodex Isokinetic Dynamometer at a velocity of 60 deg/s. Subjects performed three maximal-effort concentric and eccentric contractions, separately, for right and left hip abduction/adduction, flexion/extension, and internal/external rotation. Surface EMGs were sampled from the gluteus maximus, gluteus medius, adductor, medial and lateral hamstring, and rectus femoris muscles during all contractions. Intraclass correlation coefficients (ICC - 2,1) and standard errors of measurement (SEM) were calculated for peak torque for each movement direction and contraction mode, while ICCs were only computed for the EMG data. Motions that demonstrated high torque reliability included concentric hip abduction (right and left), flexion (right and left), extension (right) and internal rotation (right and left), and eccentric hip abduction (left), adduction (left), flexion (right), and extension (right and left) (ICC range=0.81-0.91). Motions with moderate torque reliability included concentric hip adduction (right), extension (left), internal rotation (left), and external rotation (right), and eccentric hip abduction and adduction (right), flexion (left), internal rotation (right and left), and external rotation (right and left) (ICC range=0.49-0.79). The majority of the EMG sampled muscles (n=12 and n=11 for concentric and eccentric contractions, respectively) demonstrated high reliability (ICC=0.81-0.95). Instances of low, or unacceptable, EMG reliability values occurred for the medial hamstring muscle of the left leg (both contraction modes) and the adductor muscle of the right leg during eccentric internal rotation. The major

  1. Anatomical variations of the deep head of Cruveilhier of the flexor pollicis brevis and its significance for the evolution of the precision grip

    PubMed Central

    Aziz, M. Ashraf

    2017-01-01

    Cruveilhier described in 1834 the human flexor pollicis brevis (FPB), a muscle of the thenar compartment, as having a superficial and a deep head, respectively, inserted onto the radial and ulnar sesamoids of the thumb. Since then, Cruveilhier’s deep head has been controversially discussed. Often this deep head is confused with Henle’s “interosseous palmaris volaris” or said to be a slip of the oblique adductor pollicis. In the 1960s, Day and Napier described anatomical variations of the insertions of Cruveilhier’s deep head, including its absence, and hypothesized, that the shift of the deep head’s insertion from ulnar to radial facilitated “true opposability” in anthropoids. Their general thesis for muscular arrangements underlying the power and precision grip is sound, but they did not delineate their deep head from Henle’s muscle or the adductor pollicis, and their description of the attachments of Cruveilhier’s deep head were too vague and not supported by a significant portion of the anatomical literature. Here, we reinvestigated Cruveilhier’s deep head to resolve the controversy about it and because many newer anatomy textbooks do not describe this muscle, while it is often an obvious functionally (writing, texting, precision grip) and clinically significant thenar muscle. For the first time, we empirically delineated Cruveilhier’s deep head from neighboring muscles with which it was previously confused. We observed 100% occurrence of the uncontested deep head in 80 human hands, displaying a similar variability of insertions as Day and Napier, but in significantly different numbers. Furthermore, we found variability in the origin and included as important landmarks the trapezoid and the ligamentum carpi radiatum. We tested the assertion regarding the evolutionary morphology and its role in the improvements in thumb movements during various precision grips. Our overall conclusions differ with respect to the developmental and

  2. An ergonomics study of thumb movements on smartphone touch screen.

    PubMed

    Xiong, Jinghong; Muraki, Satoshi

    2014-01-01

    This study investigated the relationships between thumb muscle activity and thumb operating tasks on a smartphone touch screen with one-hand posture. Six muscles in the right thumb and forearm were targeted in this study, namely adductor pollicis, flexor pollicis brevis, abductor pollicis brevis (APB), abductor pollicis longus, first dorsal interosseous (FDI) and extensor digitorum. The performance measures showed that the thumb developed fatigue rapidly when tapping on smaller buttons (diameter: 9 mm compared with 3 mm), and moved more slowly in flexion-extension than in adduction-abduction orientation. Meanwhile, the electromyography and perceived exertion values of FDI significantly increased in small button and flexion-extension tasks, while those of APB were greater in the adduction-abduction task. This study reveals that muscle effort among thumb muscles on a touch screen smartphone varies according to the task, and suggests that the use of small touch buttons should be minimised for better thumb performance.

  3. Muscle tension line concept in nasolabial muscle complex--based on 3-dimensional reconstruction of nasolabial muscle fibers.

    PubMed

    Yin, Ningbei; Wu, Jiajun; Chen, Bo; Song, Tao; Ma, Hengyuan; Zhao, Zhenmin; Wang, Yongqian; Li, Haidong; Wu, Di

    2015-03-01

    Plastic surgeons have attempted various ways to rebuild the aesthetic subunits of the upper lip in patients with cleft lip with less than perfect results in most cases. We propose that repairing the 3 muscle tension line groups in the nasolabial complex will have improved aesthetic results. Micro-computed tomographic scans were performed on the nasolabial tissues of 5 normal aborted fetuses and used to construct a 3-dimensional model to study the nasolabial muscle complex structure. The micro-computed tomographic (CT) scans showed the close relationship and interaction between the muscle fibers of nasalis, pars peripheralis, levator labii superioris, and pars marginalis. Based on the 2-dimensional images obtained from the micro-computed tomographic scans, we suggest the concept of nasolabial muscle complex and muscle tension line group theory: there is a close relationship among the alar part of the nasalis, depressor septi muscle, orbicularis oris muscle, and levator labii superioris alaeque nasi. The tension line groups are 3 tension line structures in the nasolabial muscle complex that interlock with each other at the intersections and maintain the specific shape and aesthetics of the lip and nose.

  4. Sumoylated α-skeletal muscle actin in the skeletal muscle of adult rats.

    PubMed

    Uda, Munehiro; Kawasaki, Hiroaki; Iizumi, Kyoichi; Shigenaga, Ayako; Baba, Takeshi; Naito, Hisashi; Yoshioka, Toshitada; Yamakura, Fumiyuki

    2015-11-01

    Skeletal muscles are composed of two major muscle fiber types: slow-twitch oxidative fibers and fast-twitch glycolytic fibers. The proteins in these muscle fibers are known to differ in their expression, relative abundance, and post-translational modifications. In this study, we report a previously unreported post-translational modification of α-skeletal muscle actin in the skeletal muscles of adult male F344 rats in vivo. Using two-dimensional electrophoresis (2D-PAGE), we first examined the differences in the protein expression profiles between the soleus and plantaris muscles. We found higher intensity protein spots at approximately 60 kDa and pH 9 on 2D-PAGE for the soleus muscle compared with the plantaris muscle. These spots were identified as α-skeletal muscle actin by liquid chromatography-nanoelectrospray ionization-tandem mass spectrometry and western blot analyses. In addition, we found that the 60 kDa α-skeletal muscle actin is modified by small ubiquitin-like modifier (SUMO) 1, using 2D-PAGE and western blot analyses. Furthermore, we found that α-skeletal muscle actin with larger molecular weight was localized in the nuclear and cytosol of the skeletal muscle, but not in the myofibrillar fraction by the combination of subcellular fractionation and western blot analyses. These results suggest that α-skeletal muscle actin is modified by SUMO-1 in the skeletal muscles, localized in nuclear and cytosolic fractions, and the extent of this modification is much higher in the slow muscles than in the fast muscles. This is the first study to show the presence of SUMOylated actin in animal tissues.

  5. Modeling Muscles

    ERIC Educational Resources Information Center

    Goodwyn, Lauren; Salm, Sarah

    2007-01-01

    Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…

  6. Differentiation of original and regenerated skeletal muscle fibres in mdx dystrophic muscles.

    PubMed

    Earnshaw, John C; Kyprianou, Phillip; Krishan, Kewal; Dhoot, Gurtej K

    2002-07-01

    The differentiation of both original muscle fibres and the regenerated muscle fibres following necrosis in mdx muscles was investigated using immunoblotting and immunocytochemical procedures. Before the onset of necrosis, postnatal skeletal muscles in mdx mouse differentiated well with only a slight delay in differentiation indicated by the level of developmental isoforms of troponin T. Prior to the onset of apparent myopathic change, both fast and slow skeletal muscle fibre types in mdx leg muscles also differentiated well when investigated by analysis of specific myosin heavy chain expression pattern. While the original muscle fibres in mdx leg muscles developed well, the differentiation of regenerated myotubes into both slow and distinct fast muscle fibre types, however, was markedly delayed or inhibited as indicated by several clusters of homogeneously staining fibres even at 14 weeks of age. The number of slow myosin heavy chain-positive myotubes amongst the regenerated muscle clusters was quite small even in soleus. This study thus established that while muscle fibres initially develop normally with only a slight delay in the differentiation process, the differentiation of regenerated myotubes in mdx muscles is markedly compromised and consequently delayed.

  7. Relationship of Skeletal Muscle Development and Growth to Breast Muscle Myopathies: A Review.

    PubMed

    Velleman, Sandra G

    2015-12-01

    Selection in meat-type birds has focused on growth rate, muscling, and feed conversion. These strategies have made substantial improvements but have affected muscle structure, repair mechanisms, and meat quality, especially in the breast muscle. The increase in muscle fiber diameters has reduced available connective tissue spacing, reduced blood supply, and altered muscle metabolism in the breast muscle. These changes have increased muscle fiber degeneration and necrosis but have limited muscle repair mechanisms mediated by the adult myoblast (satellite cell) population of cells, likely resulting in the onset of myopathies. This review focuses on muscle growth mechanisms and how changes in the cellular development of the breast muscle may be associated with breast muscle myopathies occurring in meat-type birds.

  8. Changes in muscle spindle firing in response to length changes of neighboring muscles

    PubMed Central

    Smilde, Hiltsje A.; Vincent, Jake A.; Baan, Guus C.; Nardelli, Paul; Lodder, Johannes C.; Mansvelder, Huibert D.; Cope, Tim C.

    2016-01-01

    Skeletal muscle force can be transmitted to the skeleton, not only via its tendons of origin and insertion but also through connective tissues linking the muscle belly to surrounding structures. Through such epimuscular myofascial connections, length changes of a muscle may cause length changes within an adjacent muscle and hence, affect muscle spindles. The aim of the present study was to investigate the effects of epimuscular myofascial forces on feedback from muscle spindles in triceps surae muscles of the rat. We hypothesized that within an intact muscle compartment, muscle spindles not only signal length changes of the muscle in which they are located but can also sense length changes that occur as a result of changing the length of synergistic muscles. Action potentials from single afferents were measured intra-axonally in response to ramp-hold release (RHR) stretches of an agonistic muscle at different lengths of its synergist, as well as in response to synergist RHRs. A decrease in force threshold was found for both soleus (SO) and lateral gastrocnemius afferents, along with an increase in length threshold for SO afferents. In addition, muscle spindle firing could be evoked by RHRs of the synergistic muscle. We conclude that muscle spindles not only signal length changes of the muscle in which they are located but also local length changes that occur as a result of changing the length and relative position of synergistic muscles. PMID:27075540

  9. Saxitoxins and okadaic acid group: accumulation and distribution in invertebrate marine vectors from Southern Chile.

    PubMed

    García, Carlos; Pérez, Francisco; Contreras, Cristóbal; Figueroa, Diego; Barriga, Andrés; López-Rivera, Américo; Araneda, Oscar F; Contreras, Héctor R

    2015-01-01

    Harmful algae blooms (HABs) are the main source of marine toxins in the aquatic environment surrounding the austral fjords in Chile. Huichas Island (Aysén) has an history of HABs spanning more than 30 years, but there is limited investigation of the bioaccumulation of marine toxins in the bivalves and gastropods from the Region of Aysén. In this study, bivalves (Mytilus chilenses, Choromytilus chorus, Aulacomya ater, Gari solida, Tagelus dombeii and Venus antiqua) and carnivorous gastropods (Argobuccinum ranelliformes and Concholepas concholepas) were collected from 28 sites. Researchers analysed the accumulation of STX-group toxins using a LC with a derivatisation post column (LC-PCOX), while lipophilic toxins (OA-group, azapiracids, pectenotoxins and yessotoxins) were analysed using LC-MS/MS with electrospray ionisation (+/-) in visceral (hepatopancreas) and non-visceral tissues (mantle, adductor muscle, gills and foot). Levels of STX-group and OA-group toxins varied among individuals from the same site. Among all tissue samples, the highest concentrations of STX-group toxins were noted in the hepatopancreas in V. antiqua (95 ± 0.1 μg STX-eq 100 g(-1)), T. dombeii (148 ± 1.4 μg STX-eq 100 g(-1)) and G. solida (3232 ± 5.2 μg STX-eq 100 g(-1); p < 0.05); in the adductor muscle in M. chilensis (2495 ± 6.4 μg STX-eq 100 g(-1); p < 0.05) and in the foot in C. concholepas (81 ± 0.7 μg STX-eq 100 g(-1)) and T. dombeii (114 ± 1.2 μg STX-eq 100 g(-1)). The highest variability of toxins was detected in G. solida, where high levels of carbamate derivatives were identified (GTXs, neoSTX and STX). In addition to the detected hydrophilic toxins, OA-group toxins were detected (OA and DTX-1) with an average ratio of ≈1:1. The highest levels of OA-group toxins were in the foot of C. concholepas, with levels of 400.3 ± 3.6 μg OA eq kg(-1) (p < 0.05) and with a toxic profile composed of 90% OA. A wide range of OA-group toxins was detected in M. chilensis with a

  10. Muscle enzyme release does not predict muscle function impairment after triathlon.

    PubMed

    Margaritis, I; Tessier, F; Verdera, F; Bermon, S; Marconnet, P

    1999-06-01

    We sought to determine the effects of a long distance triathlon (4 km swim, 120 km bike-ride, and 30 km run) on the four-day kinetics of the biochemical markers of muscle damage, and whether they were quantitatively linked with muscle function impairment and soreness. Data were collected from 2 days before until 4 days after the completion of the race. Twelve triathletes performed the triathlon and five did not. Maximal voluntary contraction (MVC), muscle soreness (DOMS) and total serum CK, CK-MB, LDH, AST and ALT activities were assessed. Significant changes after triathlon completion were found for all muscle damage indirect markers over time (p < 0.0001). MVC of the knee extensor and flexor muscles decreased over time (p < 0.05). There is disparity in the time point at which peak values where reached for DOMS, MVC and enzyme leakage. There is no correlation between serum enzyme leakage, DOMS and MVC impairment which occur after triathlon. Long distance triathlon race caused muscle damage, but extent, as well as muscle recovery cannot be evaluated by the magnitude of changes in serum enzyme activities. Muscle enzyme release cannot be used to predict the magnitude of the muscle function impairment caused by muscle damage.

  11. [A study on vowel duration and word length of adductor spasmodic dysphonia].

    PubMed

    Chen, Zhipeng; Ge, Pingjiang

    2016-03-01

    To understand the vowel duration and statement reading of the adductor spasmodic dysphonia (ADSD) patients compared with their normal controls, and provide ideas for clinical diagnosis and treatment. Twenty-nine ADSD patients were included in the research, with 31 normal controls. All subjects filled in form voice handicap index (VHI) by themselves. Maximum phonetic time (MPT) and maximum loudness phonetic time(MLPT) were tested on /a/ sound for all patients. Also, all the patients were required to read aloud a standard mandarin assay named , duration were measured with Praat5. 0 software after sounds were collected. A one-way t-test was performed to compare spasmodic group with control group on VHI, MPT, MLPT and duration for reading standard sentences. Pearson/Spearman correlation was tested. Result: The VHI of the 29 ADSD patients is 89±12, and their normal controls 15±16, indicating that the VHI in ADSD group is significantly higher than in the control group(P<0. 01). The MPT of the ADSD group is(16. 9±9. 8 s), and the control group is (25. 3±10.0)s, indicating that MPT in the ADSD group is significantly shorter than the control group(P<0. 01). The MLPT of the ADSD group is (15.7±7. 6)s, and the control group is (26. 5±11. 4)s, indicating that MLPT in the ADSD group is significantly shorter than the control group (P<0. 01). The duration of standard sentence reading of the ADSD group is (55.0±14. 2)s, and the control group is (37. 8±4. 8)s, indicating that the duration of standard sentence reading in the ADSD group is significantly longer than the control group (P<0. 01). Correlation analysis showed that MPT and MLPT are related within the ADSD group(r=0. 697,P< 0.01), other indexes being tested have no significant correlations. The voice disorder condition of the ADSD patients is significantly worse than normal people. Their pronunciations on continuous vowels are not lasting compared with normal people. In the meantime, their ability to

  12. Muscle Strength and Muscle Mass in Older Patients during Hospitalization: The EMPOWER Study

    PubMed Central

    Van Ancum, Jeanine M.; Scheerman, Kira; Pierik, Vincent D.; Numans, Siger T.; Verlaan, Sjors; Smeenk, Hanne E.; Slee-Valentijn, Monique; Kruizinga, Roeliene C.; Meskers, Carel G.M.; Maier, Andrea B.

    2017-01-01

    Background Low muscle strength and muscle mass are associated with an increased length of hospital stay and higher mortality rate in inpatients. To what extent hospitalization affects muscle strength and muscle mass is unclear. Objective We aimed to assess muscle strength and muscle mass at admission and during hospitalization in older patients and its relation with being at risk of geriatric conditions. Methods The EMPOWER study included patients aged 70 years and older, admitted to 4 wards of the VU University Medical Center in the Netherlands between April and December 2015. At admission, patients were screened for being at risk of 4 geriatric conditions: delirium, falls, malnutrition, and functional disability. At admission and at discharge, muscle strength and muscle mass were assessed. Results A total of 373 patients (mean age, standard deviation [SD]: 79.6, 6.38 years) were included at admission, and 224 patients (mean age, SD: 80.1, 6.32 years) at discharge. At admission, lower muscle strength in both female and male patients and low muscle mass in male patients were associated with being at risk of a higher cumulative number of geriatric conditions. Muscle strength increased during hospitalization, but no change in muscle mass was observed. Changes in muscle measures were not associated with being at risk of geriatric conditions. Discussion Older patients with lower muscle strength and muscle mass at admission were at risk of a higher cumulative number of geriatric conditions. However, being at risk of geriatric conditions did not forecast further decrease in muscle strength and muscle mass during hospitalization PMID:28817825

  13. Muscle Strength and Muscle Mass in Older Patients during Hospitalization: The EMPOWER Study.

    PubMed

    Van Ancum, Jeanine M; Scheerman, Kira; Pierik, Vincent D; Numans, Siger T; Verlaan, Sjors; Smeenk, Hanne E; Slee-Valentijn, Monique; Kruizinga, Roeliene C; Meskers, Carel G M; Maier, Andrea B

    2017-01-01

    Low muscle strength and muscle mass are associated with an increased length of hospital stay and higher mortality rate in inpatients. To what extent hospitalization affects muscle strength and muscle mass is unclear. We aimed to assess muscle strength and muscle mass at admission and during hospitalization in older patients and its relation with being at risk of geriatric conditions. The EMPOWER study included patients aged 70 years and older, admitted to 4 wards of the VU University Medical Center in the Netherlands between April and December 2015. At admission, patients were screened for being at risk of 4 geriatric conditions: delirium, falls, malnutrition, and functional disability. At admission and at discharge, muscle strength and muscle mass were assessed. A total of 373 patients (mean age, standard deviation [SD]: 79.6, 6.38 years) were included at admission, and 224 patients (mean age, SD: 80.1, 6.32 years) at discharge. At admission, lower muscle strength in both female and male patients and low muscle mass in male patients were associated with being at risk of a higher cumulative number of geriatric conditions. Muscle strength increased during hospitalization, but no change in muscle mass was observed. Changes in muscle measures were not associated with being at risk of geriatric conditions. Older patients with lower muscle strength and muscle mass at admission were at risk of a higher cumulative number of geriatric conditions. However, being at risk of geriatric conditions did not forecast further decrease in muscle strength and muscle mass during hospitalization. © 2017 The Author(s) Published by S. Karger AG, Basel.

  14. Building Muscles, Keeping Muscles: Protein Turnover During Space Flight

    NASA Technical Reports Server (NTRS)

    Ferrando, Arny; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

    2002-01-01

    As we age we lose muscle mass and strength. The problem is a matter of use it or lose it and more - a fact to which any active senior can attest. An imbalance in the natural cycle of protein turnover may be a contributing factor to decreased muscle mass. But the answer is not so simple, since aging is associated with changes in hormones, activity levels, nutrition, and often, disease. The human body constantly uses amino acids to build muscle protein, which then breaks down and must be replaced. When protein turnover gets out of balance, so that more protein breaks down than the body can replace, the result is muscle loss. This is not just the bane of aging, however. Severely burned people may have difficulty building new muscle long after the burned skin has been repaired. Answers to why we lose muscle mass and strength - and how doctors can fix it - may come from space. Astronauts usually eat a well-balanced diet and maintain an exercise routine to stay in top health. During long-duration flight, they exercise regularly to reduce the muscle loss that results from being in a near-weightless environment. Despite these precautions, astronauts lose muscle mass and strength during most missions. They quickly recover after returning to Earth - this is a temporary condition in an otherwise healthy population. Members of the STS-107 crew are participating in a study of the effects of space flight, hormone levels, and stress on protein turnover. When we are under stress, the body responds with a change in hormone levels. Researchers hypothesize that this stress-induced change in hormones along with the near-weightlessness might result in the body synthesizing less muscle protein, causing muscles to lose their strength and size. Astronauts, who must perform numerous duties in a confined and unusual environment, experience some stress during their flight, making them excellent candidates for testing the researchers' hypothesis.

  15. Muscle oxygenation and fascicle length during passive muscle stretching in ballet-trained subjects.

    PubMed

    Otsuki, A; Fujita, E; Ikegawa, S; Kuno-Mizumura, M

    2011-07-01

    Muscle stretching transiently decreases muscle-blood flow corresponding to a muscle extension. It may disturb a balance between muscular oxygen demand and oxygen supply to muscles and reduce muscle oxygenation. However, muscle-stretching training may improve blood circulatory condition, resulting in the maintained muscle oxygenation during muscle stretching. The aim of this study was to investigate changes in muscle-blood volume (tHb) and tissue oxygenation index (TOI) during muscle stretching determined by using near-infrared spectroscopy (NIRS) in ballet-trained (BT) and untrained (C) subjects. 11 BT women who regularly perform muscle stretching and 11 C women participated in this study. Fascicle lengths, tHb and TOI in the tibialis anterior muscle were measured during passive plantar flexion from ankle joint angles of 120° (baseline) to 140°, 160°, the maximal comfortable position without pain (CP), and the maximal position (MP). At 160°, the % fascicle-length change from baseline was significantly lower in the BT than the C group, however, for the changes in tHb and TOI the significant interaction effect between the 2 groups was not detected. On the other hand, although the increases in the fascicle length from baseline to CP and MP were greater in BT than C, the tHb and TOI reductions were comparable between groups. We concluded that it appears that BT can extend their muscles without excessive reduction in muscle-blood volume and muscle oxygenation at relatively same but absolutely greater muscle-stretching levels than C. The attenuation in these indices during high-level muscle stretching may be associated with the repetitive muscle stretching of long-term ballet training. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Bottom Feeding and Beyond: How the Premaxillary Protrusion of Cypriniforms Allowed for a Novel Kind of Suction Feeding.

    PubMed

    Hernandez, L Patricia; Staab, Katie Lynn

    2015-07-01

    While much of the functional work on suction feeding has involved members of Acanthopterygii, an earlier cypriniform radiation led to over 3200 species filling nearly every freshwater trophic niche. Within the great majority of acanthomorph clades that have been investigated suction feeding and the underlying morphology responsible for the generation of rapid suction have been largely conserved. This conserved feeding-apparatus is often associated with increasing the force experienced by the prey item, thus making a strike on elusive prey more effective. Cypriniforms' trophic anatomy is comprised of a number of novelties used for benthic feeding, which characterized early members of this clade. The modified cypriniform structure of the oral jaws represents a situation in which a particular type of suction feeding allowed for probing the benthos with a more functionally maneuverable anatomy. Requisite evolutionary modifications included origin and elongation of a median kinethmoid, duplications of certain divisions of the muscles of the adductor mandibulae, and origin of a dorsal, intra-buccal muscular palatal organ used in winnowing detritus. The elongated kinethmoid (coupled with modified adductor muscles) allowed for a type of premaxillary protrusion that decoupled the upper and lower jaws, enabled premaxillary protrusions with a closed mouth, and facilitated benthic feeding by increasing functional flexibility. The resultant flow of fluid generated by cypriniforms is also quite flexible, with multiple instances of peak flow in a single feeding event. This greatly modified morphology allowed for a degree of kinematic maneuverability not seen within most acanthomorphs. Later cypriniform radiations into piscivorous, insectivorous, or planktivorous feeding guilds were associated with shortening of the kinethmoid and with simplified morphology of the adductor, likely involving an emphasis on ram feeding. Although this suite of morphological novelties seemingly

  17. A comparison of the VHI, VHI-10, and V-RQOL for measuring the effect of botox therapy in adductor spasmodic dysphonia.

    PubMed

    Morzaria, Sanjay; Damrose, Edward J

    2012-05-01

    Although disease-specific quality-of-life (QOL) instruments are an invaluable outcome measure in spasmodic dysphonia, there is no consensus on which QOL instrument should be used. To determine the responsiveness of the Voice Handicap Index (VHI), Voice Handicap Index-10 (VHI-10), and Voice-Related Quality of Life (V-RQOL) to the treatment effect of botulinum toxin (Botox) in adductor spasmodic dysphonia (ADSD). Stanford University Voice and Swallowing Center. Prospective case series (level of evidence=4). Consecutive ADSD patients with a stable Botox dose-response relationship were recruited prospectively. VHI, VHI-10, and V-RQOL scores were obtained pretreatment and during the middle third of the posttreatment injection cycle. Thrity-seven patients completed the follow-up. The average total Botox dose was 0.88 units. The average follow-up time after injection was 7.84 weeks. The pretreatment QOL scores reflected the burden of the disease. All the three instruments were highly correlated in subscale and total scores. After treatment, all three instruments showed significant improvement. The VHI, VHI-10, and V-RQOL all reflected the morbidity associated with ADSD and were significantly responsive to the effect of Botox therapy. The choice of instrument should be based on physician preference. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  18. Structure-function relationship of skeletal muscle provides inspiration for design of new artificial muscle

    NASA Astrophysics Data System (ADS)

    Gao, Yingxin; Zhang, Chi

    2015-03-01

    A variety of actuator technologies have been developed to mimic biological skeletal muscle that generates force in a controlled manner. Force generation process of skeletal muscle involves complicated biophysical and biochemical mechanisms; therefore, it is impossible to replace biological muscle. In biological skeletal muscle tissue, the force generation of a muscle depends not only on the force generation capacity of the muscle fiber, but also on many other important factors, including muscle fiber type, motor unit recruitment, architecture, structure and morphology of skeletal muscle, all of which have significant impact on the force generation of the whole muscle or force transmission from muscle fibers to the tendon. Such factors have often been overlooked, but can be incorporated in artificial muscle design, especially with the discovery of new smart materials and the development of innovative fabrication and manufacturing technologies. A better understanding of the physiology and structure-function relationship of skeletal muscle will therefore benefit the artificial muscle design. In this paper, factors that affect muscle force generation are reviewed. Mathematical models used to model the structure-function relationship of skeletal muscle are reviewed and discussed. We hope the review will provide inspiration for the design of a new generation of artificial muscle by incorporating the structure-function relationship of skeletal muscle into the design of artificial muscle.

  19. Aerobic metabolism on muscle contraction in porcine gastric smooth muscle.

    PubMed

    Kanda, Hidenori; Kaneda, Takeharu; Nagai, Yuta; Urakawa, Norimoto; Shimizu, Kazumasa

    2018-05-18

    Exposure to chronic hypoxic conditions causes various gastric diseases, including gastric ulcers. It has been suggested that gastric smooth muscle contraction is associated with aerobic metabolism. However, there are no reports on the association between gastric smooth muscle contraction and aerobic metabolism, and we have investigated this association in the present study. High K + - and carbachol (CCh)-induced muscle contractions involved increasing O 2 consumption. Aeration with N 2 (hypoxia) and NaCN significantly decreased high K + - and CCh-induced muscle contraction and O 2 consumption. In addition, hypoxia and NaCN significantly decreased creatine phosphate (PCr) contents in the presence of high K + . Moreover, decrease in CCh-induced contraction and O 2 consumption was greater than that of high K + . Our results suggest that hypoxia and NaCN inhibit high K + - and CCh-induced contractions in gastric fundus smooth muscles by decreasing O 2 consumption and intracellular PCr content. However, the inhibition of CCh-induced muscle contraction was greater than that of high K + -induced muscle contraction.

  20. The tymbal muscle of cicada has flight muscle-type sarcomeric architecture and protein expression.

    PubMed

    Iwamoto, Hiroyuki

    2017-01-01

    The structural and biochemical features of the tymbal (sound-producing) muscle of cicadas were studied by X-ray diffraction and immunochemistry, and compared with those of flight muscles from the same species. The X-ray diffraction pattern of the tymbal muscle was very similar to that of the dorsal longitudinal flight muscle: In both muscles, the 2,0 equatorial reflection is much more intense than the 1,1, indicating that both muscles have a flight muscle-type myofilament lattice. In rigor, the first myosin/actin layer line reflection was finely lattice-sampled, indicating that the contractile proteins are arranged with a crystalline regularity as in asynchronous flight muscles. In contrast, the diffraction pattern from the tensor muscle, which modulates the sound by stressing the tymbal, did not show signs of such high regularity or flight muscle-type filament lattice. Electrophoretic patterns of myofibrillar proteins were also very similar in the tymbal muscle and flight muscles, but distinct from those from the tensor or leg muscles. The antibody raised against the flight muscle-specific troponin-I isoform reacted with an 80-kDa band from both tymbal and flight muscles, but with none of the bands from the tensor or leg muscles. The close similarities of the structural and biochemical profiles between the tymbal and the flight muscles suggest the possibility that a set of flight muscle-specific proteins is diverted to the tymbal muscle to meet its demand for fast, repetitive contractions.

  1. An allometric analysis of the number of muscle spindles in mammalian skeletal muscles

    PubMed Central

    Banks, R W

    2006-01-01

    An allometric analysis of the number of muscle spindles in relation to muscle mass in mammalian (mouse, rat, guinea-pig, cat, human) skeletal muscles is presented. It is shown that the trend to increasing number as muscle mass increases follows an isometric (length) relationship between species, whereas within a species, at least for the only essentially complete sample (human), the number of spindles scales, on average, with the square root rather than the cube root of muscle mass. An attempt is made to reconcile these apparently discrepant relationships. Use of the widely accepted spindle density (number of spindles g−1 of muscle) as a measure of relative abundance of spindles in different muscles is shown to be grossly misleading. It is replaced with the residuals of the linear regression of ln spindle number against ln muscle mass. Significant differences in relative spindle abundance as measured by residuals were found between regional groups of muscles: the greatest abundance is in axial muscles, including those concerned with head position, whereas the least is in muscles of the shoulder girdle. No differences were found between large and small muscles operating in parallel, or between antigravity and non-antigravity muscles. For proximal vs. distal muscles, spindles were significantly less abundant in the hand than the arm, but there was no difference between the foot and the leg. PMID:16761976

  2. Kinesthetic illusions attenuate experimental muscle pain, as do muscle and cutaneous stimulation.

    PubMed

    Gay, André; Aimonetti, Jean-Marc; Roll, Jean-Pierre; Ribot-Ciscar, Edith

    2015-07-30

    In the present study, muscle pain was induced experimentally in healthy subjects by administrating hypertonic saline injections into the tibialis anterior (TA) muscle. We first aimed at comparing the analgesic effects of mechanical vibration applied to either cutaneous or muscle receptors of the TA or to both types simultaneously. Secondly, pain alleviation was compared in subjects in whom muscle tendon vibration evoked kinesthetic illusions of the ankle joint. Muscle tendon vibration, which primarily activated muscle receptors, reduced pain intensity by 30% (p<0.01). In addition, tangential skin vibration reduced pain intensity by 33% (p<0.01), primarily by activating cutaneous receptors. Concurrently stimulating both sensory channels induced stronger analgesic effects (-51%, p<0.01), as shown by the lower levels of electrodermal activity. The strongest analgesic effects of the vibration-induced muscle inputs occurred when illusory movements were perceived (-38%, p=0.01). The results suggest that both cutaneous and muscle sensory feedback reduce muscle pain, most likely via segmental and supraspinal processes. Further clinical trials are needed to investigate these new methods of muscle pain relief. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Decellularised skeletal muscles allow functional muscle regeneration by promoting host cell migration.

    PubMed

    Urciuolo, Anna; Urbani, Luca; Perin, Silvia; Maghsoudlou, Panagiotis; Scottoni, Federico; Gjinovci, Asllan; Collins-Hooper, Henry; Loukogeorgakis, Stavros; Tyraskis, Athanasios; Torelli, Silvia; Germinario, Elena; Fallas, Mario Enrique Alvarez; Julia-Vilella, Carla; Eaton, Simon; Blaauw, Bert; Patel, Ketan; De Coppi, Paolo

    2018-05-30

    Pathological conditions affecting skeletal muscle function may lead to irreversible volumetric muscle loss (VML). Therapeutic approaches involving acellular matrices represent an emerging and promising strategy to promote regeneration of skeletal muscle following injury. Here we investigated the ability of three different decellularised skeletal muscle scaffolds to support muscle regeneration in a xenogeneic immune-competent model of VML, in which the EDL muscle was surgically resected. All implanted acellular matrices, used to replace the resected muscles, were able to generate functional artificial muscles by promoting host myogenic cell migration and differentiation, as well as nervous fibres, vascular networks, and satellite cell (SC) homing. However, acellular tissue mainly composed of extracellular matrix (ECM) allowed better myofibre three-dimensional (3D) organization and the restoration of SC pool, when compared to scaffolds which also preserved muscular cytoskeletal structures. Finally, we showed that fibroblasts are indispensable to promote efficient migration and myogenesis by muscle stem cells across the scaffolds in vitro. This data strongly support the use of xenogeneic acellular muscles as device to treat VML conditions in absence of donor cell implementation, as well as in vitro model for studying cell interplay during myogenesis.

  4. Muscle fibre recruitment can respond to the mechanics of the muscle contraction.

    PubMed

    Wakeling, James M; Uehli, Katrin; Rozitis, Antra I

    2006-08-22

    This study investigates the motor unit recruitment patterns between and within muscles of the triceps surae during cycling on a stationary ergometer at a range of pedal speeds and resistances. Muscle activity was measured from the soleus (SOL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) using surface electromyography (EMG) and quantified using wavelet and principal component analysis. Muscle fascicle strain rates were quantified using ultrasonography, and the muscle-tendon unit lengths were calculated from the segmental kinematics. The EMG intensities showed that the body uses the SOL relatively more for the higher-force, lower-velocity contractions than the MG and LG. The EMG spectra showed a shift to higher frequencies at faster muscle fascicle strain rates for MG: these shifts were independent of the level of muscle activity, the locomotor load and the muscle fascicle strain. These results indicated that a selective recruitment of the faster motor units occurred within the MG muscle in response to the increasing muscle fascicle strain rates. This preferential recruitment of the faster fibres for the faster tasks indicates that in some circumstances motor unit recruitment during locomotion can match the contractile properties of the muscle fibres to the mechanical demands of the contraction.

  5. Postmortem 31P magnetic resonance spectroscopy of the skeletal muscle: α-ATP/Pi ratio as a forensic tool?

    PubMed

    Schmidt, Tony M; Wang, Zhiyue J; Keller, Sarah; Heinemann, Axel; Acar, Suzan; Graessner, Joachim; Schoennagel, Bjoern P; Adam, Gerhard; Fischer, Roland; Yamamura, Jin

    2014-09-01

    Phosphor magnetic resonance spectroscopy ((31)P MRS) is an established method for metabolic examinations of resting and exercising skeletal muscle. So far, there are few MRS investigations of human corpses. The aim of this study was to investigate the temporal postmortem pattern of phosphor metabolites in the adductor magnus muscle and to check the value of MRS as a forensic tool, especially for the determination of the time of death. Eight corpses, died of natural cause, were examined (5 males, 3 females; age: 73±7 y, weight 65.8±15.9 kg). A control group of 3 subjects (2 males, 1 female, mean age: 51±24 y, range: 24-69 y, mean body weight: 84.0±16.5 kg) was examined at a single time point as well. (31)P MRS was performed on a 1.5 T MRI (TR 700 ms, TE 0.35 ms, averages 256, flip angle 90°). A standard (31)P/(1)H heart/liver coil was employed (receiver coil diameter 12 cm). The (31)P MRS scans were repeated in intervals of 1 h over a period from 4.5 to 24 h postmortem (p.m.). The core temperature was rectally measured throughout the MRI examination. The mean core temperature decreased from 36.0°C to 25.7°C. In vivo and ex vivo spectra showed characteristic differences, especially the PCr metabolite was no longer detectable after 10 h p.m. The α-ATP/Pi ratio decreased with time from 0.445 to 0.032 over 24 h p.m. There is a characteristic postmortem time pattern of the phosphor metabolites. Especially the acquired α-ATP/Pi ratio could be described by a significant exponential time course (r(2)=0.92, p<0.001). (31)P MRS might be added to the postmortem imaging methods. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Relationship between function of masticatory muscle in mouse and properties of muscle fibers.

    PubMed

    Abe, Shinichi; Hiroki, Emi; Iwanuma, Osamu; Sakiyama, Koji; Shirakura, Yoshitaka; Hirose, Daiki; Shimoo, Yoshiaki; Suzuki, Masashi; Ikari, Yasutoyo; Kikuchi, Ryusuke; Ide, Yoshinobu; Yoshinari, Masao

    2008-05-01

    Mammals exhibit marked morphological differences in the muscles surrounding the jaw bone due to differences in eating habits. Furthermore, the myofiber properties of the muscles differ with function. Since the muscles in the oral region have various functions such as eating, swallowing, and speech, it is believed that the functional role of each muscle differs. Therefore, to clarify the functional role of each masticatory muscle, the myofiber properties of the adult mouse masticatory muscles were investigated at the transcriptional level. Expression of MyHC-2b with a fast contraction rate and strong force was frequently noted in the temporal and masseter muscles. This suggests that the temporal and masseter muscles are closely involved in rapid antero-posterior masticatory movement, which is characteristic in mice. Furthermore, expression of MyHC-1 with a low contraction rate and weak continuous force was frequently detected in the lateral pterygoid muscle. This suggests that, in contrast to other masticatory muscles, mouse lateral pterygoid muscle is not involved in fast masticatory movement, but is involved in functions requiring continuous force such as retention of jaw position. This study revealed that muscles with different roles function comprehensively during complicated masticatory movement.

  7. The Need for Standardized Assessment of Muscle Quality in Skeletal Muscle Function Deficit and Other Aging-Related Muscle Dysfunctions: A Symposium Report.

    PubMed

    Correa-de-Araujo, Rosaly; Harris-Love, Michael O; Miljkovic, Iva; Fragala, Maren S; Anthony, Brian W; Manini, Todd M

    2017-01-01

    A growing body of scientific literature suggests that not only changes in skeletal muscle mass, but also other factors underpinning muscle quality, play a role in the decline in skeletal muscle function and impaired mobility associated with aging. A symposium on muscle quality and the need for standardized assessment was held on April 28, 2016 at the International Conference on Frailty and Sarcopenia Research in Philadelphia, Pennsylvania. The purpose of this symposium was to provide a venue for basic science and clinical researchers and expert clinicians to discuss muscle quality in the context of skeletal muscle function deficit and other aging-related muscle dysfunctions. The present article provides an expanded introduction concerning the emerging definitions of muscle quality and a potential framework for scientific inquiry within the field. Changes in muscle tissue composition, based on excessive levels of inter- and intra-muscular adipose tissue and intramyocellular lipids, have been found to adversely impact metabolism and peak force generation. However, methods to easily and rapidly assess muscle tissue composition in multiple clinical settings and with minimal patient burden are needed. Diagnostic ultrasound and other assessment methods continue to be developed for characterizing muscle pathology, and enhanced sonography using sensors to provide user feedback and improve reliability is currently the subject of ongoing investigation and development. In addition, measures of relative muscle force such as specific force or grip strength adjusted for body size have been proposed as methods to assess changes in muscle quality. Furthermore, performance-based assessments of muscle power via timed tests of function and body size estimates, are associated with lower extremity muscle strength may be responsive to age-related changes in muscle quality. Future aims include reaching consensus on the definition and standardized assessments of muscle quality, and

  8. The Effect of Adductor-Canal-Blockade on Outcome after Medial Unicondylar Knee Arthroplasty: A Preliminary Study.

    PubMed

    Brown, Matthew L; Seyler, Thorsten M; Allen, John; Plate, Johannes F; Henshaw, Daryl S; Lang, Jason E

    2015-03-01

    Unicondylar knee arthroplasty (UKA) offers decreased morbidity, faster recovery, better functional outcomes, and equivalent survivorship compared to TKA for certain patients. To fully capture these benefits, regional anesthesia techniques must facilitate rather than compromise patients ability for early postoperative mobilization and safe discharge following UKA. The purpose of this study was to determine whether the predominantly sensory adductor canal blockade (ACB) shortens hospital stay after medial UKA (mUKA). Secondary endpoints were narcotic consumption, steps walked during PT sessions, and total PT sessions required prior to discharge. Twelve patients scheduled for elective mUKA received spinal anesthesia and single-shot ACB. ACB patients were matched by age, gender, body mass index (BMI), and Charlson Comorbidity Index in a 1:2 ratio to 24 lumbar plexus block (LPB) patients. Time to hospital discharge, number of physical therapy (PT) sessions required for safe discharge, and steps taken during PT sessions were retrospectively abstracted from each patient's medical record. Patients who received ACB had a significantly shorter hospital stay (27.8 ± 3.9 hours) compared with patients who received LPB (39.7 ±18.5 hours, p = 0.025). Patients treated with ACB required significantly fewer PT sessions (1.3 ± 0.6 sessions) compared to patients who received LPB (2.4 ± 1.5 sessions, p = 0.007). Patients treated with ACB walked significantly more steps during their first PT session (225.0 ± 156.6 steps) compared with patients treated with LPB (107.4 ± 170.0, p = 0.045). There was a trend towards decreased narcotic requirements in the ACB group. Data from our study suggests that ACB may permit earlier hospital discharge and better participation in PT without compromising the quality of perioperative analgesia. Thus, ACB may represent a promising option for patients undergoing mUKA in terms of improved clinical outcomes, decreased postoperative morbidity, and cost-effectiveness.

  9. Neural effects of muscle stretching on the spinal reflexes in multiple lower-limb muscles.

    PubMed

    Masugi, Yohei; Obata, Hiroki; Inoue, Daisuke; Kawashima, Noritaka; Nakazawa, Kimitaka

    2017-01-01

    While previous studies have shown that muscle stretching suppresses monosynaptic spinal reflex excitability in stretched muscles, its effects on non-stretched muscles is still largely unknown. The purpose of this study was to examine the effects of muscle stretching on monosynaptic spinal reflex in non-stretched muscles. Ten healthy male subjects participated in this study. Muscle stretching of the right triceps surae muscle was performed using a motor torque device for 1 minute. Three different dorsiflexion torques (at approximately 5, 10, and 15 Nm) were applied during muscle stretching. Spinal reflexes evoked by transcutaneous spinal cord stimulation were recorded in both the lower-limb muscles before, during, and at 0 and 5 min following muscle stretching. The amplitudes of the spinal reflexes in both the stretched and non-stretched muscles in the right (ipsilateral) leg were smaller during stretching compared to before, and at 0 and 5 min after stretching. Furthermore, the degree of reduction in the amplitude of the spinal reflexes in the right (ipsilateral) leg muscles increased significantly as the dorsiflexion torque (i.e., stretching of the right triceps surae muscles) increased. In contrast, reduction in the amplitude of the spinal reflexes with increasing dorsiflexion torque was not seen in the left (contralateral) leg muscles. Our results clearly indicate that muscle stretching has inhibitory effects on monosynaptic spinal reflexes, not only in stretched muscles, but also in non-stretched muscles of the ipsilateral leg.

  10. Neural effects of muscle stretching on the spinal reflexes in multiple lower-limb muscles

    PubMed Central

    Obata, Hiroki; Inoue, Daisuke; Kawashima, Noritaka; Nakazawa, Kimitaka

    2017-01-01

    While previous studies have shown that muscle stretching suppresses monosynaptic spinal reflex excitability in stretched muscles, its effects on non-stretched muscles is still largely unknown. The purpose of this study was to examine the effects of muscle stretching on monosynaptic spinal reflex in non-stretched muscles. Ten healthy male subjects participated in this study. Muscle stretching of the right triceps surae muscle was performed using a motor torque device for 1 minute. Three different dorsiflexion torques (at approximately 5, 10, and 15 Nm) were applied during muscle stretching. Spinal reflexes evoked by transcutaneous spinal cord stimulation were recorded in both the lower-limb muscles before, during, and at 0 and 5 min following muscle stretching. The amplitudes of the spinal reflexes in both the stretched and non-stretched muscles in the right (ipsilateral) leg were smaller during stretching compared to before, and at 0 and 5 min after stretching. Furthermore, the degree of reduction in the amplitude of the spinal reflexes in the right (ipsilateral) leg muscles increased significantly as the dorsiflexion torque (i.e., stretching of the right triceps surae muscles) increased. In contrast, reduction in the amplitude of the spinal reflexes with increasing dorsiflexion torque was not seen in the left (contralateral) leg muscles. Our results clearly indicate that muscle stretching has inhibitory effects on monosynaptic spinal reflexes, not only in stretched muscles, but also in non-stretched muscles of the ipsilateral leg. PMID:28662201

  11. Vascular delay improves latissimus dorsi muscle perfusion and muscle function for use in cardiomyoplasty.

    PubMed

    Carroll, S M; Heilman, S J; Stremel, R W; Tobin, G R; Barker, J H

    1997-04-01

    Ischemia of the distal portion of the latissimus dorsi muscle occurs in muscle transfer for cardiomyoplasty and reduces distal muscle contractility and thus the mechanical effectiveness of cardiomyoplasty. We hypothesized that muscle function would be improved by a vascular delay procedure that increases distal muscle perfusion of the latissimus dorsi muscle. The latissimus dorsi muscles of 10 adult mongrel dogs were subjected to a vascular delay procedure on one side and a sham procedure on the other. Following 10 days of vascular delay, muscle perfusion was measured with a laser-Doppler perfusion imager before and after elevation of the muscles as flaps based only on their thoracodorsal neurovascular pedicles. The muscles were wrapped and sutured around silicone chambers (simulating cardiomyoplasty), a stimulating electrode was placed around each thoracodorsal nerve, and the muscles were stimulated to contract in both rhythmic and tetanic fashion. Circumferential (distal and middle latissimus dorsi muscle function) force generation and fatigue rates were measured independently. Circumferential muscle force, circumferential and longitudinal fatigue rate, and distal, middle, and overall perfusion were significantly (p < 0.05) improved in delayed muscle compared with nondelayed muscle. We found that a vascular delay procedure and a 10-day delay adaptation period significantly improve latissimus dorsi muscle flap perfusion and function, particularly in the distal and middle portions of the muscle. Delay should be considered as a means of improving the clinical outcome in cardiomyoplasty.

  12. Characteristics of locomotion, muscle strength, and muscle tissue in regenerating rat skeletal muscles.

    PubMed

    Iwata, Akira; Fuchioka, Satoshi; Hiraoka, Koichi; Masuhara, Mitsuhiko; Kami, Katsuya

    2010-05-01

    Although numerous studies have aimed to elucidate the mechanisms used to repair the structure and function of injured skeletal muscles, it remains unclear how and when movement recovers following damage. We performed a temporal analysis to characterize the changes in movement, muscle function, and muscle structure after muscle injury induced by the drop-mass technique. At each time-point, movement recovery was determined by ankle kinematic analysis of locomotion, and functional recovery was represented by isometric force. As a histological analysis, the cross-sectional area of myotubes was measured to examine structural regeneration. The dorsiflexion angle of the ankle, as assessed by kinematic analysis of locomotion, increased after injury and then returned to control levels by day 14 post-injury. The isometric force returned to normal levels by day 21 post-injury. However, the size of the myotubes did not reach normal levels, even at day 21 post-injury. These results indicate that recovery of locomotion occurs prior to recovery of isometric force and that functional recovery occurs earlier than structural regeneration. Thus, it is suggested that recovery of the movement and function of injured skeletal muscles might be insufficient as markers for estimating the degree of neuromuscular system reconstitution.

  13. Muscle spindle autogenetic inhibition in the extraocular muscles of lamb.

    PubMed

    Pettorossi, V E; Filippi, G M

    1981-09-01

    The role of extraocular muscle (EOM) proprioceptors on eye motility has been investigated in lambs on "encéphale isolé", by evaluating the tension of EOMs at various lengths and velocities of stretch before and after proprioceptive blocks. The EOM tension, in the absence of proprioceptive input, was higher than in normal conditions. Such an effect occurred at lengthening values greater than 3 mm of stretch from resting muscle length, corresponding to 18 degrees of eye deviation and was dependent on the velocity of the stretch, being more effective at high velocity. The muscle receptors responsible for this effect was determined by comparing the sensitivity to vibratory stimulation of spindles and tendon organs to the amount of inhibition provoked by the same stimulation on an EOM electromyographic activity. The tension inhibition appeared to be correlated to muscle spindle activation. Thus, the presence of muscle spindles can determine a reduction of the tension within the stretched muscles. This result suggests that the EOM length and velocity signals operate moment to moment reduction on the stiffness of the muscle which antagonizes eye displacement, thus facilitating the ocular movements.

  14. Inhibition of muscle spindle afferent activity during masseter muscle fatigue in the rat.

    PubMed

    Brunetti, Orazio; Della Torre, Giovannella; Lucchi, Maria Luisa; Chiocchetti, Roberto; Bortolami, Ruggero; Pettorossi, Vito Enrico

    2003-09-01

    The influence of muscle fatigue on the jaw-closing muscle spindle activity has been investigated by analyzing: (1) the field potentials evoked in the trigeminal motor nucleus (Vmot) by trigeminal mesencephalic nucleus (Vmes) stimulation, (2) the orthodromic and antidromic responses evoked in the Vmes by stimulation of the peripheral and central axons of the muscle proprioceptive afferents, and (3) the extracellular unitary discharge of masseter muscle spindles recorded in the Vmes. The masseter muscle was fatigued by prolonged tetanic masseter nerve electrical stimulation. Pre- and postsynaptic components of the potentials evoked in the Vmot showed a significant reduction in amplitude following muscle fatigue. Orthodromic and antidromic potentials recorded in the Vmes also showed a similar amplitude decrease. Furthermore, muscle fatigue caused a decrease of the discharge frequency of masseter muscle spindle afferents in most of the examined units. The inhibition of the potential amplitude and discharge frequency was strictly correlated with the extent of muscle fatigue and was mediated by the group III and IV afferent muscle fibers activated by fatigue. In fact, the inhibitory effect was abolished by capsaicin injection in the masseter muscle that provokes selective degeneration of small afferent muscle fibers containing neurokinins. We concluded that fatigue signals originating from the muscle and traveling through capsaicin-sensitive fibers are able to diminish the proprioceptive input by a central presynaptic influence. In the second part of the study, we examined the central projection of the masseter small afferents sensitive to capsaicin at the electron-microscopic level. Fiber degeneration was induced by injecting capsaicin into the masseter muscle. Degenerating terminals were found on the soma and stem process in Vmes and on the dendritic tree of neurons in Vmot. This suggests that small muscle afferents may influence the muscle spindle activity through

  15. Sleep, Muscle Mass and Muscle Function in Older People.

    PubMed

    Buchmann, Nikolaus; Spira, Dominik; Norman, Kristina; Demuth, Ilja; Eckardt, Rahel; Steinhagen-Thiessen, Elisabeth

    2016-04-15

    Loss of muscle mass, particularly in old age, can restrict mobility and physical function. Sleep is thought to play a key role in the maintenance of muscle mass; sleep disturbances have a prevalence of 6-30% in Germany. In this study, based on data from the Berlin Aging Study II (BASE-II), we analyze the relationship between sleep efficiency and quality on the one hand, and muscle mass and muscle function on the other. We analyzed cross-sectional data from 1196 subjects (52.5% women; 68 ± 4 years). Sleep behavior was assessed with questions from the Pittsburgh Sleep Quality Index; appendicular lean mass (ALM) with dual x-ray absorp - tiometry; and muscle function with a measure of grip strength and with questionnaires about physical activity and impairment of physical activities. Low muscle mass was determined from the ALM corrected by the body-mass index (BMI), i.e., from the ratio ALM/BMI. 19.1% of the women and 13.4% of the men reported poor sleep quality. Men whose ALM/BMI ratio was below the cutoff value for low muscle mass more frequently reported very poor sleep efficiency (9.1% , versus 4.8% in women; p<0.002). The adjusted odds ratio for low muscle mass was 2.8 for men with poor sleep quality (95% confidence interval: [1.1; 6.7]) and 4.3 for men with poor sleep efficiency [1.2; 15.1]. In women, there was no statistically significant association between sleep quality and efficiency on the one hand and ALM/BMI values below cutoff on the other, but poor sleep quality was found to be associated with reduced grip strength (16.25 kg ± 2.33 kg versus 15.67 kg ± 2.38 kg; p = 0.009) and low appendicular lean mass (ALM: 16.25 kg ± 2.33 kg versus 15.67 kg ± 2.38 kg; p = 0.016). These findings support the hypothesis of a link between sleep and muscle mass. The dependence of muscle mass on sleep behavior needs to be investigated in longitudinal studies.

  16. Lower Cognitive Function in Older Patients with Lower Muscle Strength and Muscle Mass.

    PubMed

    van Dam, Romee; Van Ancum, Jeanine M; Verlaan, Sjors; Scheerman, Kira; Meskers, Carel G M; Maier, Andrea B

    2018-06-18

    Low muscle strength and muscle mass are associated with adverse outcomes in older hospitalized patients. The aim of this study was to assess the association between cognitive functioning and muscle strength and muscle mass in hospitalized older patients. This prospective inception cohort included 378 patients aged 70 years or older. At admission patients were assessed for cognitive functioning by use of the Six-Item Cognitive Impairment Test (6-CIT). Muscle strength and muscle mass were assessed using handheld dynamometry and segmental multifrequency bioelectrical impedance analysis, within 48 h after admission and on day 7, or earlier on the day of discharge. The data of 371 patients (mean age ± standard deviation 80.1 ± 6.4 years, 49.3% female) were available for analyses. The median (interquartile range) 6-CIT score was 4 (0-8) points. At admission, lower cognitive functioning was associated with lower muscle strength, lower skeletal muscle mass (SMM), lower appendicular lean mass, and lower SMM index. Cognitive functioning was not associated with change in muscle strength and muscle mass during hospitalization. This study further strengthens evidence for an association between lower cognitive functioning and lower muscle strength and muscle mass, but without a further decline during hospitalization. © 2018 The Author(s) Published by S. Karger AG, Basel.

  17. US in pubalgia

    PubMed Central

    Balconi, Giuseppe

    2011-01-01

    There is considerable confusion over the word “pubalgia” with regard to the definition and the etiological causes of this condition. The term pubalgia should be used to indicate disabling pain affecting the pubic region in people who practise sports. Pubalgia affects 10% of those who practise sports and it is particularly prevalent in football players. According to the literature, about 40% of cases of pubalgia are caused by overuse of the symphysis pubis with progressive lesions affecting the rectus abdominal muscles, adductors (rectal-adductor syndrome) and the symphysis itself (osteitis pubis and joint injury). An initial study of the tendons is carried out by ultrasound (US) whereas magnetic resonance imaging (MRI) should be performed to study the bones and joints. Another 40% of cases of pubalgia are caused by "sports hernia" defined as anteroinferior abdominal wall insufficiency. These alterations can only be identified at dynamic US examination. About 20% of cases of pubalgia are caused by diseases of the neighboring structures or joints such as diseases of the hip, iliopsoas, hamstring, sacred iliac or nerves, or by urogenital diseases. PMID:23396870

  18. US in pubalgia.

    PubMed

    Balconi, Giuseppe

    2011-09-01

    There is considerable confusion over the word "pubalgia" with regard to the definition and the etiological causes of this condition. The term pubalgia should be used to indicate disabling pain affecting the pubic region in people who practise sports. Pubalgia affects 10% of those who practise sports and it is particularly prevalent in football players. According to the literature, about 40% of cases of pubalgia are caused by overuse of the symphysis pubis with progressive lesions affecting the rectus abdominal muscles, adductors (rectal-adductor syndrome) and the symphysis itself (osteitis pubis and joint injury). An initial study of the tendons is carried out by ultrasound (US) whereas magnetic resonance imaging (MRI) should be performed to study the bones and joints.Another 40% of cases of pubalgia are caused by "sports hernia" defined as anteroinferior abdominal wall insufficiency. These alterations can only be identified at dynamic US examination.About 20% of cases of pubalgia are caused by diseases of the neighboring structures or joints such as diseases of the hip, iliopsoas, hamstring, sacred iliac or nerves, or by urogenital diseases.

  19. Chronic hypoxia and low salinity impair anti-predatory responses of the green-lipped mussel Perna viridis.

    PubMed

    Wang, Youji; Hu, Menghong; Cheung, S G; Shin, P K S; Lu, Weiqun; Li, Jiale

    2012-06-01

    The effects of chronic hypoxia and low salinity on anti-predatory responses of the green-lipped mussel Perna viridis were investigated. Dissolved oxygen concentrations ranged from hypoxic to normoxic (1.5 ± 0.3 mg l(-1), 3.0 ± 0.3 mg l(-1) and 6.0 ± 0.3 mg l(-1)), and salinities were selected within the variation during the wet season in Hong Kong coastal waters (15‰, 20‰, 25‰ and 30‰). The dissolved oxygen and salinity significantly affected some anti-predatory responses of mussel, including byssus production, shell thickness and shell weight, and the adductor diameter was only significantly affected by salinity. Besides, interactive effects of dissolved oxygen and salinity on the byssus production and shell thickness were also observed. In hypoxic and low salinity conditions, P. viridis produced fewer byssal threads, thinner shell and adductor muscle, indicating that hypoxia and low salinity are severe environmental stressors for self-defence of mussel, and their interactive effects further increase the predation risk. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  20. Healthy Muscles Matter

    MedlinePlus

    ... How can I keep my muscles more healthy? Physical activity Muscles that are not used will get smaller ... heart muscle as well! Get 60 minutes of physical activity every day. Get 60 minutes of physical activity ...

  1. Skeletal muscle atrophy in bioengineered skeletal muscle: a new model system.

    PubMed

    Lee, Peter H U; Vandenburgh, Herman H

    2013-10-01

    Skeletal muscle atrophy has been well characterized in various animal models, and while certain pathways that lead to disuse atrophy and its associated functional deficits have been well studied, available drugs to counteract these deficiencies are limited. An ex vivo tissue-engineered skeletal muscle offers a unique opportunity to study skeletal muscle physiology in a controlled in vitro setting. Primary mouse myoblasts isolated from adult muscle were tissue engineered into bioartificial muscles (BAMs) containing hundreds of aligned postmitotic muscle fibers expressing sarcomeric proteins. When electrically stimulated, BAMs generated measureable active forces within 2-3 days of formation. The maximum isometric tetanic force (Po) increased for ∼3 weeks to 2587±502 μN/BAM and was maintained at this level for greater than 80 days. When BAMs were reduced in length by 25% to 50%, muscle atrophy occurred in as little as 6 days. Length reduction resulted in significant decreases in Po (50.4%), mean myofiber cross-sectional area (21.7%), total protein synthesis rate (22.0%), and noncollagenous protein content (6.9%). No significant changes occurred in either the total metabolic activity or protein degradation rates. This study is the first in vitro demonstration that length reduction alone can induce skeletal muscle atrophy, and establishes a novel in vitro model for the study of skeletal muscle atrophy.

  2. Muscle atrophy

    MedlinePlus

    ... muscle atrophy may include: Burns Long-term corticosteroid therapy Malnutrition Muscular dystrophy and other diseases of the muscle Osteoarthritis Rheumatoid arthritis Home Care An exercise program ...

  3. The Impact of Muscle Disuse on Muscle Atrophy in Severely Burned Rats

    DTIC Science & Technology

    2010-12-01

    Following muscle collection from the right hindlimb, muscle isometric force of PL and SL was measured simultaneously in the left hindlimb under...37.5°C by manually adjusting the temperature of cir culating water in the rat surgical bed. The isometric force of the PL and SL muscles was then...the physiologic cross sectional area (CSA) of PL and SL was calculated using the following formula: CSA= ( muscle mass) × cos θ ( muscle fiber

  4. Objective evaluation of muscle strength in infants with hypotonia and muscle weakness.

    PubMed

    Reus, Linda; van Vlimmeren, Leo A; Staal, J Bart; Janssen, Anjo J W M; Otten, Barto J; Pelzer, Ben J; Nijhuis-van der Sanden, Maria W G

    2013-04-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17 infants with Prader-Willi Syndrome (PWS) aged 24 months. The inter-rater reliability of the measurement method was good (ICC=.84) and the convergent validity was confirmed by high Pearson's correlations between muscle strength, age, height, and weight (r=.79-.85). A multiple linear regression model was developed to predict muscle strength based on age, height, and weight, explaining 73% of the variance in muscle strength. In infants with PWS, muscle strength was significantly decreased. Pearson's correlations showed that infants with PWS in which muscle strength was more severely affected also had a larger motor developmental delay (r=.75). Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Bone Marrow Stromal Cells Generate Muscle Cells and Repair Muscle Degeneration

    NASA Astrophysics Data System (ADS)

    Dezawa, Mari; Ishikawa, Hiroto; Itokazu, Yutaka; Yoshihara, Tomoyuki; Hoshino, Mikio; Takeda, Shin-ichi; Ide, Chizuka; Nabeshima, Yo-ichi

    2005-07-01

    Bone marrow stromal cells (MSCs) have great potential as therapeutic agents. We report a method for inducing skeletal muscle lineage cells from human and rat general adherent MSCs with an efficiency of 89%. Induced cells differentiated into muscle fibers upon transplantation into degenerated muscles of rats and mdx-nude mice. The induced population contained Pax7-positive cells that contributed to subsequent regeneration of muscle upon repetitive damage without additional transplantation of cells. These MSCs represent a more ready supply of myogenic cells than do the rare myogenic stem cells normally found in muscle and bone marrow.

  6. Cricothyroid muscle and thyroarytenoid muscle dominance in vocal register control: preliminary results.

    PubMed

    Kochis-Jennings, Karen Ann; Finnegan, Eileen M; Hoffman, Henry T; Jaiswal, Sanyukta; Hull, Darcey

    2014-09-01

    Headmix and head registers use cricothyroid (CT) muscle dominant voicing, whereas chest and chestmix registers use thyroarytenoid (TA) muscle dominant voicing. Cross-sectional study. CT and TA electromyographic data obtained from five untrained singers and two trained singers were analyzed to determine CT and TA muscle dominance as a function of register. Simultaneous recordings of TA and CT muscle activity and audio were obtained during production of pitch glides and a variety of midrange and upper pitches in chest, chestmix, headmix, and head registers. TA dominant phonation was only observed for chest productions and headmix/head register productions below 300 Hz. All phonation above 300 Hz, regardless of register, showed CT:TA muscle activity ratios that were CT dominant or close to 1, indicating nearly equal CT and TA muscle activity. This was true for all subjects on all vocal tasks. For the subjects sampled in this study, pitch level appeared to have a greater effect on TA and CT muscle dominance than vocal register. Preliminary findings regarding CT and TA dominance and register control do not support the assumption that all chest and chestmix production has greater TA muscle activity than CT muscle activity or that all headmix and head production require greater CT muscle activity than TA muscle activity. The data indicate that pitch level may play a greater role in determining TA and CT dominance than register. Copyright © 2014 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  7. Complement activation promotes muscle inflammation during modified muscle use

    NASA Technical Reports Server (NTRS)

    Frenette, J.; Cai, B.; Tidball, J. G.

    2000-01-01

    Modified muscle use can result in muscle inflammation that is triggered by unidentified events. In the present investigation, we tested whether the activation of the complement system is a component of muscle inflammation that results from changes in muscle loading. Modified rat hindlimb muscle loading was achieved by removing weight-bearing from the hindlimbs for 10 days followed by reloading through normal ambulation. Experimental animals were injected with the recombinant, soluble complement receptor sCR1 to inhibit complement activation. Assays for complement C4 or factor B in sera showed that sCR1 produced large reductions in the capacity for activation of the complement system through both the classical and alternative pathways. Analysis of complement C4 concentration in serum in untreated animals showed that the classical pathway was activated during the first 2 hours of reloading. Analysis of factor B concentration in untreated animals showed activation of the alternative pathway at 6 hours of reloading. Administration of sCR1 significantly attenuated the invasion of neutrophils (-49%) and ED1(+) macrophages (-52%) that occurred in nontreated animals after 6 hours of reloading. The presence of sCR1 also reduced significantly the degree of edema by 22% as compared to untreated animals. Together, these data show that increased muscle loading activated the complement system which then briefly contributes to the early recruitment of inflammatory cells during modified muscle loading.

  8. Respiratory Muscle Plasticity

    PubMed Central

    Gransee, Heather M.; Mantilla, Carlos B.; Sieck, Gary C.

    2014-01-01

    Muscle plasticity is defined as the ability of a given muscle to alter its structural and functional properties in accordance with the environmental conditions imposed on it. As such, respiratory muscle is in a constant state of remodeling, and the basis of muscle’s plasticity is its ability to change protein expression and resultant protein balance in response to varying environmental conditions. Here, we will describe the changes of respiratory muscle imposed by extrinsic changes in mechanical load, activity, and innervation. Although there is a large body of literature on the structural and functional plasticity of respiratory muscles, we are only beginning to understand the molecular-scale protein changes that contribute to protein balance. We will give an overview of key mechanisms regulating protein synthesis and protein degradation, as well as the complex interactions between them. We suggest future application of a systems biology approach that would develop a mathematical model of protein balance and greatly improve treatments in a variety of clinical settings related to maintaining both muscle mass and optimal contractile function of respiratory muscles. PMID:23798306

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

    PubMed

    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% (P<0·001) and soleus fibre size was reduced by 8·5 ± 13% (P = 0·016). However, WoRPD remained unaffected as indicated by an unchanged loss of relative plantar flexor power between pre- and postexperiments (P = 0·88). Blood flow, 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.

  10. The effect of muscle excursion on muscle recovery after tendon repair in a neglected tendon injury: a study in rabbit soleus muscles.

    PubMed

    Jeon, Suk Ha; Chung, Moon Sang; Baek, Goo Hyun; Lee, Young Ho; Gong, Hyun Sik

    2011-01-01

    We attempted to determine whether muscle excursion observed during operation can be a prognostic indicator of muscle recovery after delayed tendon repair in a rabbit soleus model. Eighteen rabbits underwent tenotomy of the soleus muscles bilaterally and were divided into three groups according to the period from tenotomy to repair. The tendons of each group were repaired 2, 4, and 6 weeks after tenotomy. The excursion of each soleus muscle was measured at the time of tenotomy (baseline), at 2, 4, 6 weeks after tenotomy, and 8 weeks after tendon repair. The amount of muscle recovery after tendon repair in terms of muscle excursion independently depended on the timing of repair and on the muscle excursion observed during repair. The regression model predicted that the muscle excursion recovered on average by 0.6% as the muscle excursion at the time of repair increased by 1% after adjusting for the timing of repair. This study suggests that measuring the muscle excursion during tendon repair may help physicians estimate the potential of muscle recovery in cases of delayed tendon repair. Copyright © 2010 Orthopaedic Research Society.

  11. Optical Cross-Sectional Muscle Area Determination of Drosophila Melanogaster Adult Indirect Flight Muscles.

    PubMed

    Selma-Soriano, Estela; Artero, Rubén; Llamusi, Beatriz

    2018-03-31

    Muscle mass wasting, known as muscle atrophy, is a common phenotype in Drosophila models of neuromuscular diseases. We have used the indirect flight muscles (IFMs) of flies, specifically the dorso-longitudinal muscles (DLM), as the experimental subject to measure the atrophic phenotype brought about by different genetic causes. In this protocol, we describe how to embed fly thorax muscles for semi thin sectioning, how to obtain a good contrast between muscle and the surrounding tissue, and how to process optical microscope images for semiautomatic acquisition of quantifiable data and analysis. We describe three specific applications of the methodological pipeline. First, we show how the method can be applied to quantify muscle degeneration in a myotonic dystrophy fly model; second, measurement of muscle cross-sectional area can help to identify genes that either promote or prevent muscle atrophy and/or muscle degeneration; third, this protocol can be applied to determine whether a candidate compound is able to significantly modify a given atrophic phenotype induced by a disease-causing mutation or by an environmental trigger.

  12. Impaired Expression of Uncoupling Protein 2 (UCP2) Causes Defective Post-ischemic Angiogenesis in Mice Deficient in AMP-activated Protein Kinase α Subunits

    PubMed Central

    Xu, Ming-Jiang; Song, Ping; Shirwany, Najeeb; Liang, Bin; Xing, Junjie; Viollet, Benoit; Wang, Xian; Zhu, Yi; Zou, Ming-Hui

    2011-01-01

    Objective The aim of the present study was to determine whether mitochondrial uncoupling protein (UCP)-2 is required for AMPK-dependent angiogenesis in ischemia in vivo. Methods and Results Angiogenesis was assayed by monitoring endothelial tube formation (a surrogate for angiogenesis) in human umbilical vein endothelial cells (HUVECs), isolated mouse aortic endothelial cells (MAECs), and pulmomary microvascular endothelial cells (PMECs), or in ischemic thigh adductor muscles from wild-type (WT) mice or mice deficient in either AMPKα1 or AMPKα2. AMPK inhibition with pharmacological inhibitor (compound C) or genetic means (transfection of AMPKα-specific siRNA) significantly lowered the tube formation in HUVECs. Consistently, compared with WT mice, tube formation in MAECs isolated from either AMPKα1−/− or AMPKα2−/− mice, which exhibited oxidative stress and reduced expression of UCP2, were significantly impaired. In addition, adenoviral overexpression of UCP2, but not adenoviruses encoding green florescence protein (GFP), normalized tube formation in MAECs from either AMPKα1−/− or AMPKα2−/− mice. Similarly, supplementation with sodium nitroprusside (SNP), a nitric oxide (NO) donor, restored tube formation. Furthermore, ischemia significantly increased angiogenesis, serine 1177 phosphorylation of endothelial NO synthase (eNOS), and UCP2 in ischemic thigh adductor muscles from WT mice, but not from either AMPKα1−/− or AMPKα2−/− mice. Conclusion We conclude that AMPK-dependent UCP2 expression in endothelial cells promotes angiogenesis in vivo. PMID:21597006

  13. Two novel elements (CFG1 and PYG1) of Mag lineage of Ty3/Gypsy retrotransposons from Zhikong scallop (Chlamys farreri) and Japanese scallop (Patinopecten yessoensis).

    PubMed

    Wang, Shi; Bao, Zhenmin; Hu, Xiaoli; Shao, Mingyu; Zhang, Lingling; Hu, Jingjie

    2008-05-01

    Two novel elements (CFG1 and PYG1) of Mag lineage of Ty3/Gypsy retrotransposons were cloned from Zhikong scallop (Chlamys farreri) and Japanese scallop (Patinopecten yessoensis). The total length of the CFG1 element is 4826 bp, including 5'-LTR (192 bp), the entire ORF (4047 bp) and 3'-LTR (189 bp). The entire ORFs of both CFG1 and PYG1 elements are composed of 1348 aa and do not have any frameshifts. Their closest relative is Jule element from the poeciliid fish (Xiphophorus maculatus). On average, the diploid genome of C. farreri contains approximately 84 copies of CFG1 elements. We summarize the major features of CFG1, PYG1 and other elements of Mag lineage of the Ty3/Gypsy group. mRNA expression of CFG1 element in larvae increases gradually before the gastrulae stage and decreases gradually afterward, whereas in adductor such expression in adductor muscle and digestive gland are lower than those in other tissues. Overall, mRNA expression of CFG1 element in the early larvae is significantly higher than that in adult tissues. In muscle tissue, while the promoter and partial GAG domain of CFG1 element are unmethylated, the partial RT domain is highly methylated. These results suggest that CFG1 expression may be controlled by a post-transcriptional gene silencing mechanism that is associated with coding-region (RT domain) methylation.

  14. Onset of rigor mortis is earlier in red muscle than in white muscle.

    PubMed

    Kobayashi, M; Takatori, T; Nakajima, M; Sakurada, K; Hatanaka, K; Ikegaya, H; Matsuda, Y; Iwase, H

    2000-01-01

    Rigor mortis is thought to be related to falling ATP levels in muscles postmortem. We measured rigor mortis as tension determined isometrically in three rat leg muscles in liquid paraffin kept at 37 degrees C or 25 degrees C--two red muscles, red gastrocnemius (RG) and soleus (SO) and one white muscle, white gastrocnemius (WG). Onset, half and full rigor mortis occurred earlier in RG and SO than in WG both at 37 degrees C and at 25 degrees C even though RG and WG were portions of the same muscle. This suggests that rigor mortis directly reflects the postmortem intramuscular ATP level, which decreases more rapidly in red muscle than in white muscle after death. Rigor mortis was more retarded at 25 degrees C than at 37 degrees C in each type of muscle.

  15. Muscle anatomy and dynamic muscle function in osteogenesis imperfecta type I.

    PubMed

    Veilleux, Louis-Nicolas; Lemay, Martin; Pouliot-Laforte, Annie; Cheung, Moira S; Glorieux, Francis H; Rauch, Frank

    2014-02-01

    Results of previous studies suggested that children and adolescents with osteogenesis imperfecta (OI) type I have a muscle force deficit. However, muscle function has only been assessed by static isometric force tests and not in more natural conditions such as dynamic force and power tests. The purpose of this study was to assess lower extremity dynamic muscle function and muscle anatomy in OI type I. The study was performed in the outpatient department of a pediatric orthopedic hospital. A total of 54 individuals with OI type I (6-21 years; 20 male) and 54 age- and sex-matched controls took part in this study. Calf muscle cross-sectional area and density were measured by peripheral quantitative computed tomography. Lower extremity muscle function (peak force per body weight and peak power per body mass) was measured by jumping mechanography through 5 tests: multiple two-legged hopping, multiple one-legged hopping, single two-legged jump, chair-rise test, and heel-rise test. Compared with age- and sex-matched controls, patients with OI type I had smaller muscle size (P = .04) but normal muscle density (P = .21). They also had lower average peak force and lower specific force (peak force/muscle cross-sectional area; all P < .008). Average peak power was lower in patients with OI type I but not significantly so (all P > .054). Children and adolescents with OI type I have, on average, a significant force deficit in the lower limb as measured by dynamic force tests. Nonetheless, these data also show that OI type I is compatible with normal muscle performance in some individuals.

  16. Evaluating swallowing muscles essential for hyolaryngeal elevation by using muscle functional magnetic resonance imaging.

    PubMed

    Pearson, William G; Hindson, David F; Langmore, Susan E; Zumwalt, Ann C

    2013-03-01

    Reduced hyolaryngeal elevation, a critical event in swallowing, is associated with radiation therapy. Two muscle groups that suspend the hyoid, larynx, and pharynx have been proposed to elevate the hyolaryngeal complex: the suprahyoid and longitudinal pharyngeal muscles. Thought to assist both groups is the thyrohyoid, a muscle intrinsic to the hyolaryngeal complex. Intensity modulated radiation therapy guidelines designed to preserve structures important to swallowing currently exclude the suprahyoid and thyrohyoid muscles. This study used muscle functional magnetic resonance imaging (mfMRI) in normal healthy adults to determine whether both muscle groups are active in swallowing and to test therapeutic exercises thought to be specific to hyolaryngeal elevation. mfMRI data were acquired from 11 healthy subjects before and after normal swallowing and after swallowing exercise regimens (the Mendelsohn maneuver and effortful pitch glide). Whole-muscle transverse relaxation time (T2 signal, measured in milliseconds) profiles of 7 test muscles were used to evaluate the physiologic response of each muscle to each condition. Changes in effect size (using the Cohen d measure) of whole-muscle T2 profiles were used to determine which muscles underlie swallowing and swallowing exercises. Post-swallowing effect size changes (where a d value of >0.20 indicates significant activity during swallowing) for the T2 signal profile of the thyrohyoid was a d value of 0.09; a d value of 0.40 for the mylohyoid, 0.80 for the geniohyoid, 0.04 for the anterior digastric, and 0.25 for the posterior digastric-stylohyoid in the suprahyoid muscle group; and d values of 0.47 for the palatopharyngeus and 0.28 for the stylopharyngeus muscles in the longitudinal pharyngeal muscle group. The Mendelsohn maneuver and effortful pitch glide swallowing exercises showed significant effect size changes for all muscles tested, except for the thyrohyoid. Muscles of both the suprahyoid and the longitudinal

  17. Detection of muscle gap by L-BIA in muscle injuries: clinical prognosis.

    PubMed

    Nescolarde, L; Yanguas, J; Terricabras, J; Lukaski, H; Alomar, X; Rosell-Ferrer, J; Rodas, G

    2017-06-21

    Sport-related muscle injury classifications are based basically on imaging criteria such as ultrasound (US) and magnetic resonance imaging (MRI) without consensus because of a lack of clinical prognostics for return-to-play (RTP), which is conditioned upon the severity of the injury, and this in turn with the muscle gap (muscular fibers retraction). Recently, Futbol Club Barcelona's medical department proposed a new muscle injury classification in which muscle gap plays an important role, with the drawback that it is not always possible to identify by MRI. Localized bioimpedance measurement (L-BIA) has emerged as a non-invasive technique for supporting US and MRI to quantify the disrupted soft tissue structure in injured muscles. To correlate the severity of the injury according to the gap with the RTP, through the percent of change in resistance (R), reactance (Xc) and phase-angle (PA) by L-BIA measurements in 22 muscle injuries. After grouping the data according to the muscle gap (by MRI exam), there were significant differences in R between grade 1 and grade 2f (myotendinous or myofascial muscle injury with feather-like appearance), as well as between grade 2f and grade 2g (myotendinous or myofascial muscle injury with feather and gap). The Xc and PA values decrease significantly between each grade (i.e. 1 versus 2f, 1 versus 2g and 2f versus 2g). In addition, the severity of the muscle gap adversely affected the RTP with significant differences observed between 1 and 2g as well as between 2f and 2g. These results show that L-BIA could aid MRI and US in identifying the severity of an injured muscle according to muscle gap and therefore to accurately predict the RTP.

  18. Muscle interleukin-6 and fasting-induced PDH regulation in mouse skeletal muscle.

    PubMed

    Gudiksen, Anders; Bertholdt, Laerke; Vingborg, Mikkel Birkkjaer; Hansen, Henriette Watson; Ringholm, Stine; Pilegaard, Henriette

    2017-03-01

    Fasting prompts a metabolic shift in substrate utilization from carbohydrate to predominant fat oxidation in skeletal muscle, and pyruvate dehydrogenase (PDH) is seen as a controlling link between the competitive oxidation of carbohydrate and fat during metabolic challenges like fasting. Interleukin (IL)-6 has been proposed to be released from muscle with concomitant effects on both glucose and fat utilization. The aim was to test the hypothesis that muscle IL-6 has a regulatory impact on fasting-induced suppression of skeletal muscle PDH. Skeletal muscle-specific IL-6 knockout (IL-6 MKO) mice and floxed littermate controls (control) were either fed or fasted for 6 or 18 h. Lack of muscle IL-6 elevated the respiratory exchange ratio in the fed and early fasting state, but not with prolonged fasting. Activity of PDH in the active form (PDHa) was higher in fed and fasted IL-6 MKO than in control mice at 18 h, but not at 6 h, whereas lack of muscle IL-6 did not prevent downregulation of PDHa activity in skeletal muscle or changes in plasma and muscle substrate levels in response to 18 h of fasting. Phosphorylation of three of four sites on PDH-E1α increased with 18 h of fasting, but was lower in IL-6 MKO mice than in control. In addition, both PDK4 mRNA and protein increased with 6 and 18 h of fasting in both genotypes, but PDK4 protein was lower in IL-6 MKO than in control. In conclusion, skeletal muscle IL-6 seems to regulate whole body substrate utilization in the fed, but not fasted, state and influence skeletal muscle PDHa activity in a circadian manner. However, skeletal muscle IL-6 is not required for maintaining metabolic flexibility in response to fasting. Copyright © 2017 the American Physiological Society.

  19. Difficulties in estimating muscle forces from muscle cross-sectional area. An example using the psoas major muscle.

    PubMed

    Gatton, M L; Pearcy, M J; Pettet, G J

    1999-07-15

    Most biomechanical models use muscle cross-sectional area (CSA) as an indicator of maximum isometric muscle force. In general, there are multiple estimates of CSA for the same muscle. For example, numerous studies have estimated the CSA of the psoas major muscle using different subject populations and positions. However, few studies have combined the available information to obtain an overall estimate of CSA or investigated the effect different subject characteristics may have on CSA. In the present update, nine studies that reported psoas major CSA or physiologic CSA were compared with respect to subject characteristics, methodology, and results. Corrections to cadaveric data were made to adjust physiologic CSA to CSA. Comparison of reported values for living subjects indicated that females have smaller mean CSA than males for the psoas major muscle and that body size does not significantly influence muscle CSA in males. Areas derived from cadaveric data were smaller than similar studies on living subjects, possibly because of subject age, removal of tendinous and fatty components of fascicles, and lack of detailed data for fascicle angles in the supine position. Results indicate that researchers who use muscle CSA in biomechanical models should carefully assess the appropriateness of the data used, particularly in relation to potential sex differences and the influence of postural changes on CSA.

  20. Assessing the effectiveness of botulinum toxin injections for adductor spasmodic dysphonia: clinician and patient perception.

    PubMed

    Braden, Maia N; Johns, Michael M; Klein, Adam M; Delgaudio, John M; Gilman, Marina; Hapner, Edie R

    2010-03-01

    To determine the effectiveness of Botox treatment for adductor spasmodic dysphonia (ADSD), the clinician and patient judge changes in voice symptoms and the effect on quality of life. Currently, there is no standard protocol for determining the effectiveness of Botox injections in treating ADSD. Therefore, clinicians use a variety of perceptual scales and patient-based self-assessments to determine patients' impressions of severity and changes after treatments. The purpose of this study was to assess clinician-patient agreement of the effects of Botox on voice quality and quality of life in ADSD. Retrospective chart review of 199 randomly selected patients since 2004. Results indicated a weak correlation between the patient's assessment of voice impairment (EIS) and patient's quality of life impairment (Voice-Related Quality of Life [V-RQOL]) in the mild-moderate dysphonia severity group and the moderate-to-severe dysphonia group. There was a weak correlation between the patient's assessment of voice impairment EIS and the clinician's perceptual judgment of voice impairment (Consensus Auditory Perceptual Evaluation of Voice [CAPE-V]) only in the moderate to severe dysphonia group. There was a weak correlation between the patient's quality of life impairment (V-RQOL) and the clinician's perceptual judgment of voice impairment (CAPE-V) only in the severe to profound dysphonia group. The poor relationship among commonly used outcome measures leads us to question how best to assess the effectiveness of Botox in ADSD. Clinicians are required to document treatment outcomes, making it important to use scales that are valid, reliable, and sensitive to change. Future research directions include examining relationships between measures both before and after Botox injections, examining the specific factors that determine quality of life changes, and further research on specific parameters of the CAPE-V as well as comparing perceptual and quality of life scales with acoustic

  1. Changes in muscle fiber contractility and extracellular matrix production during skeletal muscle hypertrophy.

    PubMed

    Mendias, Christopher L; Schwartz, Andrew J; Grekin, Jeremy A; Gumucio, Jonathan P; Sugg, Kristoffer B

    2017-03-01

    Skeletal muscle can adapt to increased mechanical loads by undergoing hypertrophy. Transient reductions in whole muscle force production have been reported during the onset of hypertrophy, but contractile changes in individual muscle fibers have not been previously studied. Additionally, the extracellular matrix (ECM) stores and transmits forces from muscle fibers to tendons and bones, and determining how the ECM changes during hypertrophy is important in understanding the adaptation of muscle tissue to mechanical loading. Using the synergist ablation model, we sought to measure changes in muscle fiber contractility, collagen content, and cross-linking, and in the expression of several genes and activation of signaling proteins that regulate critical components of myogenesis and ECM synthesis and remodeling during muscle hypertrophy. Tissues were harvested 3, 7, and 28 days after induction of hypertrophy, and nonoverloaded rats served as controls. Muscle fiber specific force (sF o ), which is the maximum isometric force normalized to cross-sectional area, was reduced 3 and 7 days after the onset of mechanical overload, but returned to control levels by 28 days. Collagen abundance displayed a similar pattern of change. Nearly a quarter of the transcriptome changed over the course of overload, as well as the activation of signaling pathways related to hypertrophy and atrophy. Overall, this study provides insight into fundamental mechanisms of muscle and ECM growth, and indicates that although muscle fibers appear to have completed remodeling and regeneration 1 mo after synergist ablation, the ECM continues to be actively remodeling at this time point. NEW & NOTEWORTHY This study utilized a rat synergist ablation model to integrate changes in single muscle fiber contractility, extracellular matrix composition, activation of important signaling pathways in muscle adaption, and corresponding changes in the muscle transcriptome to provide novel insight into the basic

  2. Changes in muscle fiber contractility and extracellular matrix production during skeletal muscle hypertrophy

    PubMed Central

    Schwartz, Andrew J.; Grekin, Jeremy A.; Gumucio, Jonathan P.; Sugg, Kristoffer B.

    2017-01-01

    Skeletal muscle can adapt to increased mechanical loads by undergoing hypertrophy. Transient reductions in whole muscle force production have been reported during the onset of hypertrophy, but contractile changes in individual muscle fibers have not been previously studied. Additionally, the extracellular matrix (ECM) stores and transmits forces from muscle fibers to tendons and bones, and determining how the ECM changes during hypertrophy is important in understanding the adaptation of muscle tissue to mechanical loading. Using the synergist ablation model, we sought to measure changes in muscle fiber contractility, collagen content, and cross-linking, and in the expression of several genes and activation of signaling proteins that regulate critical components of myogenesis and ECM synthesis and remodeling during muscle hypertrophy. Tissues were harvested 3, 7, and 28 days after induction of hypertrophy, and nonoverloaded rats served as controls. Muscle fiber specific force (sFo), which is the maximum isometric force normalized to cross-sectional area, was reduced 3 and 7 days after the onset of mechanical overload, but returned to control levels by 28 days. Collagen abundance displayed a similar pattern of change. Nearly a quarter of the transcriptome changed over the course of overload, as well as the activation of signaling pathways related to hypertrophy and atrophy. Overall, this study provides insight into fundamental mechanisms of muscle and ECM growth, and indicates that although muscle fibers appear to have completed remodeling and regeneration 1 mo after synergist ablation, the ECM continues to be actively remodeling at this time point. NEW & NOTEWORTHY This study utilized a rat synergist ablation model to integrate changes in single muscle fiber contractility, extracellular matrix composition, activation of important signaling pathways in muscle adaption, and corresponding changes in the muscle transcriptome to provide novel insight into the basic

  3. Evaluating Swallowing Muscles Essential for Hyolaryngeal Elevation by Using Muscle Functional Magnetic Resonance Imaging

    PubMed Central

    Pearson, William G.; Hindson, David F.; Langmore, Susan E.; Zumwalt, Ann C.

    2012-01-01

    Summary Elevation of the larynx is critical to swallowing function, an observation supported by the fact that radiation therapy-induced dysphagia is associated with reduced laryngeal elevation. We investigated muscles underlying hyolaryngeal elevation by using muscle functional MRI. We acquired scans from 11 healthy subjects to determine whole-muscle T2 signal profiles pre-swallowing, post-swallowing, and after performing swallowing exercises. Results demonstrate muscles essential to laryngeal elevation and exercises that target them. Purpose Reduced hyolaryngeal elevation, a critical event in swallowing, is associated with radiation therapy. Two muscle groups that suspend the hyoid, larynx, and pharynx have been proposed to elevate the hyolaryngeal complex: the suprahyoid and longitudinal pharyngeal muscles. Thought to assist both groups is the thyrohyoid, a muscle intrinsic to the hyolaryngeal complex. Intensity modulated radiation therapy guidelines designed to preserve structures important to swallowing currently exclude the suprahyoid and thyrohyoid muscles. This study used muscle functional magnetic resonance imaging (mfMRI) in normal healthy adults to determine whether both muscle groups are active in swallowing and to test therapeutic exercises thought to be specific to hyolaryngeal elevation. Methods and Materials mfMRI data were acquired from 11 healthy subjects before and after normal swallowing and after swallowing exercise regimens (the Mendelsohn maneuver and effortful pitch glide). Whole-muscle transverse relaxation time (T2 signal, measured in milliseconds) profiles of 7 test muscles were used to evaluate the physiologic response of each muscle to each condition. Changes in effect size (using the Cohen d measure) of whole-muscle T2 profiles were used to determine which muscles underlie swallowing and swallowing exercises. Results Post-swallowing effect size changes (where a d value of >0.20 indicates significant activity during swallowing) for the T

  4. In Vitro Tissue-Engineered Skeletal Muscle Models for Studying Muscle Physiology and Disease.

    PubMed

    Khodabukus, Alastair; Prabhu, Neel; Wang, Jason; Bursac, Nenad

    2018-04-25

    Healthy skeletal muscle possesses the extraordinary ability to regenerate in response to small-scale injuries; however, this self-repair capacity becomes overwhelmed with aging, genetic myopathies, and large muscle loss. The failure of small animal models to accurately replicate human muscle disease, injury and to predict clinically-relevant drug responses has driven the development of high fidelity in vitro skeletal muscle models. Herein, the progress made and challenges ahead in engineering biomimetic human skeletal muscle tissues that can recapitulate muscle development, genetic diseases, regeneration, and drug response is discussed. Bioengineering approaches used to improve engineered muscle structure and function as well as the functionality of satellite cells to allow modeling muscle regeneration in vitro are also highlighted. Next, a historical overview on the generation of skeletal muscle cells and tissues from human pluripotent stem cells, and a discussion on the potential of these approaches to model and treat genetic diseases such as Duchenne muscular dystrophy, is provided. Finally, the need to integrate multiorgan microphysiological systems to generate improved drug discovery technologies with the potential to complement or supersede current preclinical animal models of muscle disease is described. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Soluble Milk Proteins Improve Muscle Mass Recovery after Immobilization-Induced Muscle Atrophy in Old Rats but Do not Improve Muscle Functional Property Restoration.

    PubMed

    Verney, J; Martin, V; Ratel, S; Chavanelle, V; Bargetto, M; Etienne, M; Chaplais, E; Le Ruyet, P; Bonhomme, C; Combaret, L; Guillet, C; Boisseau, N; Sirvent, P; Dardevet, D

    2017-01-01

    Effect of 3 different dairy protein sources on the recovery of muscle function after limb immobilization in old rats. Longitudinal animal study. Institut National de la Recherche Agronomique (INRA). The study took part in a laboratory setting. Old rats were subjected to unilateral hindlimb immobilization for 8 days and then allowed to recover with 3 different dietary proteins: casein, soluble milk proteins or whey proteins for 49 days. Body weight, muscle mass, muscle fibre size, isometric, isokinetic torque, muscle fatigability and muscle oxidative status were measured before and at the end of the immobilization period and during the recovery period i.e 7, 21, 35 and 49 days post immobilization. In contrast to the casein diet, soluble milk proteins and whey proteins were efficient to favor muscle mass recovery after cast immobilization during aging. By contrast, none of the 3 diary proteins was able to improve muscle strength, power and fatigability showing a discrepancy between the recovery of muscle mass and function. However, the soluble milk proteins allowed a better oxidative capacity in skeletal muscle during the rehabilitation period. Whey proteins and soluble milk proteins improve muscle mass recovery after immobilization-induced muscle atrophy in old rats but do not allow muscle functional property restoration.

  6. The roles of muscle stem cells in muscle injury, atrophy and hypertrophy.

    PubMed

    Fukada, So-Ichiro

    2018-05-01

    Skeletal muscle is composed of multinuclear cells called myofibers. Muscular dystrophy (a genetic muscle disorder) induces instability in the cell membrane of myofibers and eventually causes myofibre damage. Non-genetic muscle disorders, including sarcopenia, diabetes, bedridden immobility and cancer cachexia, lead to atrophy of myofibres. In contrast, resistance training induces myofibre hypertrophy. Thus, myofibres exhibit a plasticity that is strongly affected by both intrinsic and extrinsic factors. There is no doubt that muscle stem cells (MuSCs, also known as muscle satellite cells) are indispensable for muscle repair/regeneration, but their contributions to atrophy and hypertrophy are still controversial. The present review focuses on the relevance of MuSCs to (i) muscle diseases and (ii) hypertrophy. Further, this review addresses fundamental questions about MuSCs to clarify the onset or progression of these diseases and which might lead to development of a MuSC-based therapy.

  7. Endurance training facilitates myoglobin desaturation during muscle contraction in rat skeletal muscle.

    PubMed

    Takakura, Hisashi; Furuichi, Yasuro; Yamada, Tatsuya; Jue, Thomas; Ojino, Minoru; Hashimoto, Takeshi; Iwase, Satoshi; Hojo, Tatsuya; Izawa, Tetsuya; Masuda, Kazumi

    2015-03-24

    At onset of muscle contraction, myoglobin (Mb) immediately releases its bound O2 to the mitochondria. Accordingly, intracellular O2 tension (PmbO2) markedly declines in order to increase muscle O2 uptake (mVO2). However, whether the change in PmbO2 during muscle contraction modulates mVO2 and whether the O2 release rate from Mb increases in endurance-trained muscles remain unclear. The purpose of this study was, therefore, to determine the effect of endurance training on O2 saturation of Mb (SmbO2) and PmbO2 kinetics during muscle contraction. Male Wistar rats were subjected to a 4-week swimming training (Tr group; 6 days per week, 30 min × 4 sets per day) with a weight load of 2% body mass. After the training period, deoxygenated Mb kinetics during muscle contraction were measured using near-infrared spectroscopy under hemoglobin-free medium perfusion. In the Tr group, the VmO2peak significantly increased by 32%. Although the PmbO2 during muscle contraction did not affect the increased mVO2 in endurance-trained muscle, the O2 release rate from Mb increased because of the increased Mb concentration and faster decremental rate in SmbO2 at the maximal twitch tension. These results suggest that the Mb dynamics during muscle contraction are contributing factors to faster VO2 kinetics in endurance-trained muscle.

  8. Endurance training facilitates myoglobin desaturation during muscle contraction in rat skeletal muscle

    PubMed Central

    Takakura, Hisashi; Furuichi, Yasuro; Yamada, Tatsuya; Jue, Thomas; Ojino, Minoru; Hashimoto, Takeshi; Iwase, Satoshi; Hojo, Tatsuya; Izawa, Tetsuya; Masuda, Kazumi

    2015-01-01

    At onset of muscle contraction, myoglobin (Mb) immediately releases its bound O2 to the mitochondria. Accordingly, intracellular O2 tension (PmbO2) markedly declines in order to increase muscle O2 uptake (mO2). However, whether the change in PmbO2 during muscle contraction modulates mO2 and whether the O2 release rate from Mb increases in endurance-trained muscles remain unclear. The purpose of this study was, therefore, to determine the effect of endurance training on O2 saturation of Mb (SmbO2) and PmbO2 kinetics during muscle contraction. Male Wistar rats were subjected to a 4-week swimming training (Tr group; 6 days per week, 30 min × 4 sets per day) with a weight load of 2% body mass. After the training period, deoxygenated Mb kinetics during muscle contraction were measured using near-infrared spectroscopy under hemoglobin-free medium perfusion. In the Tr group, the mO2peak significantly increased by 32%. Although the PmbO2 during muscle contraction did not affect the increased mO2 in endurance-trained muscle, the O2 release rate from Mb increased because of the increased Mb concentration and faster decremental rate in SmbO2 at the maximal twitch tension. These results suggest that the Mb dynamics during muscle contraction are contributing factors to faster O2 kinetics in endurance-trained muscle. PMID:25801957

  9. Maximum shortening velocity of lymphatic muscle approaches that of striated muscle.

    PubMed

    Zhang, Rongzhen; Taucer, Anne I; Gashev, Anatoliy A; Muthuchamy, Mariappan; Zawieja, David C; Davis, Michael J

    2013-11-15

    Lymphatic muscle (LM) is widely considered to be a type of vascular smooth muscle, even though LM cells uniquely express contractile proteins from both smooth muscle and cardiac muscle. We tested the hypothesis that LM exhibits an unloaded maximum shortening velocity (Vmax) intermediate between that of smooth muscle and cardiac muscle. Single lymphatic vessels were dissected from the rat mesentery, mounted in a servo-controlled wire myograph, and subjected to isotonic quick release protocols during spontaneous or agonist-evoked contractions. After maximal activation, isotonic quick releases were performed at both the peak and plateau phases of contraction. Vmax was 0.48 ± 0.04 lengths (L)/s at the peak: 2.3 times higher than that of mesenteric arteries and 11.4 times higher than mesenteric veins. In cannulated, pressurized lymphatic vessels, shortening velocity was determined from the maximal rate of constriction [rate of change in internal diameter (-dD/dt)] during spontaneous contractions at optimal preload and minimal afterload; peak -dD/dt exceeded that obtained during any of the isotonic quick release protocols (2.14 ± 0.30 L/s). Peak -dD/dt declined with pressure elevation or activation using substance P. Thus, isotonic methods yielded Vmax values for LM in the mid to high end (0.48 L/s) of those the recorded for phasic smooth muscle (0.05-0.5 L/s), whereas isobaric measurements yielded values (>2.0 L/s) that overlapped the midrange of values for cardiac muscle (0.6-3.3 L/s). Our results challenge the dogma that LM is classical vascular smooth muscle, and its unusually high Vmax is consistent with the expression of cardiac muscle contractile proteins in the lymphatic vessel wall.

  10. Distributions of nerve and muscle fibre types in locust jumping muscle.

    PubMed

    Hoyle, G

    1978-04-01

    Muscle fibres of the locust extensor tibiae (jumping muscle) were examined by interference microscopy and by electron microscopy. The electrical responses of single fibres and the mechanical responses of bundles or selected regions to the nerve fibres were examined. Four axons innervate the muscle: fast (FETi), slow (SETi), common inhibitor (CI) and dorsal unpaired median (DUMETi). Their distributions were examined by combined electrophysiological tracing and EM sectioning. The mean diameter of muscle fibres in different regions varies from 40 to 140 micrometer and is related to the local leg thickness rather than muscle fibre type. The fine structure of a fibre is related to its innervation. Fibres innervated by FETi but not SETi are of fast type ultrastructurally. Fibres innervated by SETi but not by FETi are of slow type ultrastructurally. Fibres innervated by both axons are generally intermediate between the extremes though more nearly of fast type than slow. Distal slow muscle fibres have much slower relaxation rates than do proximal ones. The most proximal bundles are of mixed muscle fibre type. There is an abrupt transition from a mixed population to homogeneous fast type, in the muscle units immediately distal to the most proximal bundles. This transition is associated with the presence of DUMETi terminals on some of the fibres distal to the transition point. There are no SETi endings on these same fibres. Fibres innervated by both SETi and FETi are scattered throughout the leg, but are commonest in the dorsal bundles. The percentage of these increases progressively passing distally. The most distal muscle fibres are innervated by SETi but not by FETi. It is concluded that different regions of the muscle will play different roles functionally since they are differentially sensitive to the pattern of SETi discharge.

  11. Muscle synergy space: learning model to create an optimal muscle synergy

    PubMed Central

    Alnajjar, Fady; Wojtara, Tytus; Kimura, Hidenori; Shimoda, Shingo

    2013-01-01

    Muscle redundancy allows the central nervous system (CNS) to choose a suitable combination of muscles from a number of options. This flexibility in muscle combinations allows for efficient behaviors to be generated in daily life. The computational mechanism of choosing muscle combinations, however, remains a long-standing challenge. One effective method of choosing muscle combinations is to create a set containing the muscle combinations of only efficient behaviors, and then to choose combinations from that set. The notion of muscle synergy, which was introduced to divide muscle activations into a lower-dimensional synergy space and time-dependent variables, is a suitable tool relevant to the discussion of this issue. The synergy space defines the suitable combinations of muscles, and time-dependent variables vary in lower-dimensional space to control behaviors. In this study, we investigated the mechanism the CNS may use to define the appropriate region and size of the synergy space when performing skilled behavior. Two indices were introduced in this study, one is the synergy stability index (SSI) that indicates the region of the synergy space, the other is the synergy coordination index (SCI) that indicates the size of the synergy space. The results on automatic posture response experiments show that SSI and SCI are positively correlated with the balance skill of the participants, and they are tunable by behavior training. These results suggest that the CNS has the ability to create optimal sets of efficient behaviors by optimizing the size of the synergy space at the appropriate region through interacting with the environment. PMID:24133444

  12. Evaluating Swallowing Muscles Essential for Hyolaryngeal Elevation by Using Muscle Functional Magnetic Resonance Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pearson, William G., E-mail: bp1@bu.edu; Hindson, David F.; Langmore, Susan E.

    2013-03-01

    Purpose: Reduced hyolaryngeal elevation, a critical event in swallowing, is associated with radiation therapy. Two muscle groups that suspend the hyoid, larynx, and pharynx have been proposed to elevate the hyolaryngeal complex: the suprahyoid and longitudinal pharyngeal muscles. Thought to assist both groups is the thyrohyoid, a muscle intrinsic to the hyolaryngeal complex. Intensity modulated radiation therapy guidelines designed to preserve structures important to swallowing currently exclude the suprahyoid and thyrohyoid muscles. This study used muscle functional magnetic resonance imaging (mfMRI) in normal healthy adults to determine whether both muscle groups are active in swallowing and to test therapeutic exercisesmore » thought to be specific to hyolaryngeal elevation. Methods and Materials: mfMRI data were acquired from 11 healthy subjects before and after normal swallowing and after swallowing exercise regimens (the Mendelsohn maneuver and effortful pitch glide). Whole-muscle transverse relaxation time (T2 signal, measured in milliseconds) profiles of 7 test muscles were used to evaluate the physiologic response of each muscle to each condition. Changes in effect size (using the Cohen d measure) of whole-muscle T2 profiles were used to determine which muscles underlie swallowing and swallowing exercises. Results: Post-swallowing effect size changes (where a d value of >0.20 indicates significant activity during swallowing) for the T2 signal profile of the thyrohyoid was a d value of 0.09; a d value of 0.40 for the mylohyoid, 0.80 for the geniohyoid, 0.04 for the anterior digastric, and 0.25 for the posterior digastric-stylohyoid in the suprahyoid muscle group; and d values of 0.47 for the palatopharyngeus and 0.28 for the stylopharyngeus muscles in the longitudinal pharyngeal muscle group. The Mendelsohn maneuver and effortful pitch glide swallowing exercises showed significant effect size changes for all muscles tested, except for the thyrohyoid

  13. Influence of temperature on muscle recruitment and muscle function in vivo.

    PubMed

    Rome, L C

    1990-08-01

    Temperature has a large influence on the maximum velocity of shortening (Vmax) and maximum power output of muscle (Q10 = 1.5-3). In some animals, maximum performance and maximum sustainable performance show large temperature sensitivities, because these parameters are dependent solely on mechanical power output of the muscles. The mechanics of locomotion (sarcomere length excursions and muscle-shortening velocities, V) at a given speed, however, are precisely the same at all temperatures. Animals compensate for the diminished power output of their muscles at low temperatures by compressing their recruitment order into a narrower range of locomotor speeds, that is, recruiting more muscle fibers and faster fiber types at a given speed. By examining V/Vmax, I calculate that fish at 10 degrees C must recruit 1.53-fold greater fiber cross section than at 20 degrees C. V/Vmax also appears to be an important design constraint in muscle. It sets the lowest V and the highest V over which a muscle can be used effectively. Because the Vmax of carp slow red muscle has a Q10 of 1.6 between 10 and 20 degrees C, the slow aerobic fibers can be used over a 1.6-fold greater range of swim speeds at the warmer temperature. In some species of fish, Vmax can be increased during thermal acclimation, enabling animals to swim at higher speeds.

  14. Muscle Session Summary

    NASA Technical Reports Server (NTRS)

    Baldwin, Kenneth; Feeback, Daniel

    1999-01-01

    Presentations from the assembled group of investigators involved in specific research projeects related to skeletal muscle in space flight can categorized in thematic subtopics: regulation of contractile protein phenotypes, muscle growth and atrophy, muscle structure: injury, recovery,and regeneration, metabolism and fatigue, and motor control and loading factors.

  15. An Autologous Muscle Tissue Expansion Approach for the Treatment of Volumetric Muscle Loss

    DTIC Science & Technology

    2015-07-01

    potential therapy for some VML indications, autologous minced muscle grafts (1mm3 pieces of muscle ) are effective in promoting remarkable de novo fiber ...may be misaligned.9–12 More recently, minced muscle grafts were effective in promoting de novomus- cle fiber regeneration and functional recovery in...to enable torque stabilization. The contribution of the tenotomized EDL muscle was negligible in this testing system.13 Peak TA muscle isometric torque

  16. Liquid-type Botulinum Toxin Type A in Adductor Spasmodic Dysphonia: A Prospective Pilot Study.

    PubMed

    Cha, Wonjae; Jang, Jeon Yeob; Wang, Soo-Geun; Kang, Ji-Heon; Jo, Min-Gyu

    2017-05-01

    Botulinum toxin (BTX) has been widely used to treat adductor spasmodic dysphonia (ADSD). Most commercially available forms of BTX require reconstitution before use, which may increase the risk of contamination and requires careful titration. Recently, a liquid-type BTX type A (BTX-A) has been developed, which should simplify the procedure and enhance its efficacy. Herein, we present a prospective pilot study to investigate the efficacy and safety of liquid-type BTX-A in the treatment of ADSD. Twenty-six consecutive liquid-type BTX-A injections were performed in 12 patients with ADSD. We included as a control group 34 consecutive patients with ADSD who had previously undergone 52 vocal fold injection procedures with freeze-dried-type BTX-A. All patients in both groups had improvement of symptoms related to ADSD and period of normal voice. Most patients experienced breathiness, and the onset time, the peak response time, and the duration of breathiness were similar in both groups. The duration of effect (days) was 96.96 ± 18.91 and 77.38 ± 18.97 in the freeze-dried-type and the liquid-type groups, and the duration of benefit (days) was 80.02 ± 18.24 and 62.69 ± 19.73 in the freeze-dried-type and the liquid-type groups. To compare the efficacy between the freeze-dried-type and the liquid-type BTX-A, the sessions of the unilateral vocal fold injection were included and were categorized as group A (1 ~ 2 units BTX-A) and group B (2 ~ 3 units BTX-A), according to the dose per vocal fold. There was no significant difference of effect time between freeze-dried-type and liquid-type BTX-A groups. No adverse events related to BTX or vocal fold injection were reported. Liquid-type BTX-A is safe and effective for the treatment of spasmodic dysphonia. With the advantages of simple preparation, storage, and reuse and animal protein-free constituents, liquid-type BTX-A may be a good option in the treatment of spasmodic dysphonia. Copyright © 2017 The

  17. Hierarchical signaling transduction of the immune and muscle cell crosstalk in muscle regeneration.

    PubMed

    Yang, Wenjun; Hu, Ping

    2018-04-01

    The muscle regeneration is a complicated bioprocess that involved in many cell types, including necrotic muscle cells, satellite cells, mesenchymal cells, pericytes, immune cells, and other cell types present at the injury site. Immune cells involved in both innate and adaptive immune responses regulate the progress of muscle regeneration. In this review, we discussed the roles of different immune cells in muscle regeneration. The immune cells regulate muscle regeneration through cytokine production, cell-cell contacts, and general immune environment regulation. We also describe the current known mechanism of how immune cells regulating muscle regeneration. Copyright © 2017. Published by Elsevier Inc.

  18. Physical principles demonstrate that the biceps femoris muscle relative to the other hamstring muscles exerts the most force: implications for hamstring muscle strain injuries.

    PubMed

    Dolman, Bronwyn; Verrall, Geoffrey; Reid, Iain

    2014-07-01

    Of the hamstring muscle group the biceps femoris muscle is the most commonly injured muscle in sports requiring interval sprinting. The reason for this observation is unknown. The objective of this study was to calculate the forces of all three hamstring muscles, relative to each other, during a lengthening contraction to assess for any differences that may help explain the biceps femoris predilection for injury during interval sprinting. To calculate the displacement of each individual hamstring muscle previously performed studies on cadaveric anatomical data and hamstring kinematics during sprinting were used. From these displacement calculations for each individual hamstring muscle physical principles were then used to deduce the proportion of force exerted by each individual hamstring muscle during a lengthening muscle contraction. These deductions demonstrate that the biceps femoris muscle is required to exert proportionally more force in a lengthening muscle contraction relative to the semimembranosus and semitendinosus muscles primarily as a consequence of having to lengthen over a greater distance within the same time frame. It is hypothesized that this property maybe a factor in the known observation of the increased susceptibility of the biceps femoris muscle to injury during repeated sprints where recurrent higher force is required.

  19. The muscle-specific ubiquitin ligase atrogin-1/MAFbx mediates statin-induced muscle toxicity

    PubMed Central

    Hanai, Jun-ichi; Cao, Peirang; Tanksale, Preeti; Imamura, Shintaro; Koshimizu, Eriko; Zhao, Jinghui; Kishi, Shuji; Yamashita, Michiaki; Phillips, Paul S.; Sukhatme, Vikas P.; Lecker, Stewart H.

    2007-01-01

    Statins inhibit HMG-CoA reductase, a key enzyme in cholesterol synthesis, and are widely used to treat hypercholesterolemia. These drugs can lead to a number of side effects in muscle, including muscle fiber breakdown; however, the mechanisms of muscle injury by statins are poorly understood. We report that lovastatin induced the expression of atrogin-1, a key gene involved in skeletal muscle atrophy, in humans with statin myopathy, in zebrafish embryos, and in vitro in murine skeletal muscle cells. In cultured mouse myotubes, atrogin-1 induction following lovastatin treatment was accompanied by distinct morphological changes, largely absent in atrogin-1 null cells. In zebrafish embryos, lovastatin promoted muscle fiber damage, an effect that was closely mimicked by knockdown of zebrafish HMG-CoA reductase. Moreover, atrogin-1 knockdown in zebrafish embryos prevented lovastatin-induced muscle injury. Finally, overexpression of PGC-1α, a transcriptional coactivator that induces mitochondrial biogenesis and protects against the development of muscle atrophy, dramatically prevented lovastatin-induced muscle damage and abrogated atrogin-1 induction both in fish and in cultured mouse myotubes. Collectively, our human, animal, and in vitro findings shed light on the molecular mechanism of statin-induced myopathy and suggest that atrogin-1 may be a critical mediator of the muscle damage induced by statins. PMID:17992259

  20. MUSCLE INJURIES IN ATHLETES

    PubMed Central

    Barroso, Guilherme Campos; Thiele, Edilson Schwansee

    2015-01-01

    This article had the aim of demonstrating the physiology, diagnosis and treatment of muscle injuries, focusing on athletes and their demands and expectations. Muscle injuries are among the most common complaints in orthopedic practice, occurring both among athletes and among non-athletes. These injuries present a challenge for specialists, due to the slow recovery, during which time athletes are unable to take part in training and competitions, and due to frequent sequelae and recurrences of the injuries. Most muscle injuries (between 10% and 55% of all injuries) occur during sports activities. The muscles most commonly affected are the ischiotibial, quadriceps and gastrocnemius. These muscles go across two joints and are more subject to acceleration and deceleration forces. The treatment for muscle injuries varies from conservative treatment to surgery. New procedures are being used, like the hyperbaric chamber and the use of growth factors. However, there is still a high rate of injury recurrence. Muscle injury continues to be a topic of much controversy. New treatments are being researched and developed, but prevention through muscle strengthening, stretching exercises and muscle balance continues to be the best “treatment”. PMID:27027021

  1. Muscle Satellite Cell Protein Teneurin‐4 Regulates Differentiation During Muscle Regeneration

    PubMed Central

    Ishii, Kana; Suzuki, Nobuharu; Mabuchi, Yo; Ito, Naoki; Kikura, Naomi; Fukada, So‐ichiro; Okano, Hideyuki; Takeda, Shin'ichi

    2015-01-01

    Abstract Satellite cells are maintained in an undifferentiated quiescent state, but during muscle regeneration they acquire an activated stage, and initiate to proliferate and differentiate as myoblasts. The transmembrane protein teneurin‐4 (Ten‐4) is specifically expressed in the quiescent satellite cells; however, its cellular and molecular functions remain unknown. We therefore aimed to elucidate the function of Ten‐4 in muscle satellite cells. In the tibialis anterior (TA) muscle of Ten‐4‐deficient mice, the number and the size of myofibers, as well as the population of satellite cells, were reduced with/without induction of muscle regeneration. Furthermore, we found an accelerated activation of satellite cells in the regenerated Ten‐4‐deficient TA muscle. The cell culture analysis using primary satellite cells showed that Ten‐4 suppressed the progression of myogenic differentiation. Together, our findings revealed that Ten‐4 functions as a crucial player in maintaining the quiescence of muscle satellite cells. Stem Cells 2015;33:3017–3027 PMID:26013034

  2. Repositioning forelimb superficialis muscles: tendon attachment and muscle activity enable active relocation of functional myofibers.

    PubMed

    Huang, Alice H; Riordan, Timothy J; Wang, Lingyan; Eyal, Shai; Zelzer, Elazar; Brigande, John V; Schweitzer, Ronen

    2013-09-16

    The muscles that govern hand motion are composed of extrinsic muscles that reside within the forearm and intrinsic muscles that reside within the hand. We find that the extrinsic muscles of the flexor digitorum superficialis (FDS) first differentiate as intrinsic muscles within the hand and then relocate as myofibers to their final position in the arm. This remarkable translocation of differentiated myofibers across a joint is dependent on muscle contraction and muscle-tendon attachment. Interestingly, the intrinsic flexor digitorum brevis (FDB) muscles of the foot are identical to the FDS in tendon pattern and delayed developmental timing but undergo limited muscle translocation, providing strong support for evolutionary homology between the FDS and FDB muscles. We propose that the intrinsic FDB pattern represents the original tetrapod limb and that translocation of the muscles to form the FDS is a mammalian evolutionary addition. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Functional characteristics of the rat jaw muscles: daily muscle activity and fiber type composition.

    PubMed

    Kawai, Nobuhiko; Sano, Ryota; Korfage, Joannes A M; Nakamura, Saika; Tanaka, Eiji; van Wessel, Tim; Langenbach, Geerling E J; Tanne, Kazuo

    2009-12-01

    Skeletal muscles have a heterogeneous fiber type composition, which reflects their functional demand. The daily muscle use and the percentage of slow-type fibers have been shown to be positively correlated in skeletal muscles of larger animals but for smaller animals there is no information. The examination of this relationship in adult rats was the purpose of this study. We hypothesized a positive relationship between the percentage of fatigue-resistant fibers in each muscle and its total duration of use per day. Fourteen Wistar strain male rats (410-450 g) were used. A radio-telemetric device was implanted to record muscle activity continuously from the superficial masseter, deep masseter, anterior belly of digastric and anterior temporalis muscles. The degree of daily muscle use was quantified by the total duration of muscle activity per day (duty time) exceeding specified levels of the peak activity (2, 5, 20 and 50%). The fiber type composition of the muscles was examined by the myosin heavy chain content of the fibers by means of immunohistochemical staining. At lower activity levels (exceeding 2 and 5% of the peak activity), the duty time of the anterior belly of digastric muscle was significantly (P < 0.01) longer than those of the other muscles. The anterior belly of digastric muscle also contained the highest percentage of slow-type fibers (type I fiber and hybrid fiber co-expressing myosin heavy chain I + IIA) (ca. 11%; P < 0.05). By regression analysis for all four muscles, an inter-muscular comparison showed a positive relationship between the duty time (exceeding 50% of the peak activity) and the percentage of type IIX fibers (P < 0.05), which demonstrate intermediate physiological properties relative to type IIA and IIB fibers. For the jaw muscles of adult male rats, the variations of fiber type composition and muscle use suggest that the muscle containing the largest amounts of slow-type fibers (the anterior belly of digastric muscle) is mainly

  4. Injury Incidence in a Spanish Sub-Elite Professional Football Team: A Prospective Study During Four Consecutive Seasons

    PubMed Central

    Mallo, Javier; González, Pablo; Veiga, Santiago; Navarro, Enrique

    2011-01-01

    The aim of this study was to investigate the injury incidence and injury characteristics of a Spanish sub-elite professional football team during four consecutive seasons. A team was followed prospectively from the season 2003-2004 to 2006-2007 and individual player exposure and time loss injuries were recorded during all club training sessions and matches. A total of 313 time-loss injuries were recorded. The mean injury incidence was 10.9 injuries/1000 hours (5.2 injuries/1000 training hours and 44.1 injuries/1000 match hours). The injury incidence during competitive matches was higher (p < 0.001) than in friendly matches (55.8 vs. 22.6 injuries/1000 hours). The incidence of major injuries (>28 days absence) was 0.4 injuries/1000 hours. The thigh was the most commonly (35%) injured region and caused 29% of all competitive match absence. Muscle injuries in the four main groups of the lower limbs (hamstrings, adductors, quadriceps and calf muscles) caused 43% of competitive match unavailability. The results of this study show that the risk to sustain a major injury in the course of the season was low for sub- elite footballers in comparison to elite players. Thigh strains were the first cause of absence in competition due to injury. Key points The incidence of major injuries (absence greater than 4 weeks) was lower in a Spanish sub-elite football team than in elite European teams. The risk of sustaining an injury was 2.5 fold higher (p < 0.001) in official than in friendly matches. Lower limb muscular (hamstrings, quadriceps, hip adductors and calf muscles) and joint (knee and ankle) injuries were the main causes of match unavailability. PMID:24149566

  5. Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

    NASA Technical Reports Server (NTRS)

    Farrell, E. R.; Fernandes, J.; Keshishian, H.

    1996-01-01

    In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

  6. Mean individual muscle activities and ratios of total muscle activities in a selective muscle strengthening experiment: the effects of lower limb muscle activity based on mediolateral slope angles during a one-leg stance.

    PubMed

    Lee, Sang-Yeol

    2016-09-01

    [Purpose] The purpose of this study was to provide basic data for research on selective muscle strengthening by identifying mean muscle activities and calculating muscle ratios for use in developing strengthening methods. [Subjects and Methods] Twenty-one healthy volunteers were included in this study. Muscle activity was measured during a one-leg stance under 6 conditions of slope angle: 0°, 5°, 10°, 15°, 20°, and 25°. The data used in the analysis were root mean square and % total muscle activity values. [Results] There were significant differences in the root mean square of the gluteus medius, the hamstring, and the medial gastrocnemius muscles. There were significant differences in % total muscle activity of the medial gastrocnemius. [Conclusion] Future studies aimed at developing selective muscle strengthening methods are likely to yield more effective results by using muscle activity ratios based on electromyography data.

  7. Hindlimb suspension reduces muscle regeneration

    NASA Technical Reports Server (NTRS)

    Mozdziak, P. E.; Truong, Q.; Macius, A.; Schultz, E.

    1998-01-01

    Exposure of juvenile skeletal muscle to a weightless environment reduces growth and satellite cell mitotic activity. However, the effect of a weightless environment on the satellite cell population during muscle repair remains unknown. Muscle injury was induced in rat soleus muscles using the myotoxic snake venom, notexin. Rats were placed into hindlimb-suspended or weightbearing groups for 10 days following injury. Cellular proliferation during regeneration was evaluated using 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and image analysis. Hindlimb suspension reduced (P < 0.05) regenerated muscle mass, regenerated myofiber diameter, uninjured muscle mass, and uninjured myofiber diameter compared to weightbearing rats. Hindlimb suspension reduced (P < 0.05) BrdU labeling in uninjured soleus muscles compared to weight-bearing muscles. However, hindlimb suspension did not abolish muscle regeneration because myofibers formed in the injured soleus muscles of hindlimb-suspended rats, and BrdU labeling was equivalent (P > 0.10) on myofiber segments isolated from the soleus muscles of hindlimb-suspended and weightbearing rats following injury. Thus, hindlimb suspension (weightlessness) does not suppress satellite cell mitotic activity in regenerating muscles before myofiber formation, but reduces growth of the newly formed myofibers.

  8. Physical principles demonstrate that the biceps femoris muscle relative to the other hamstring muscles exerts the most force: implications for hamstring muscle strain injuries

    PubMed Central

    Dolman, Bronwyn; Verrall, Geoffrey; Reid, Iain

    2014-01-01

    Summary Of the hamstring muscle group the biceps femoris muscle is the most commonly injured muscle in sports requiring interval sprinting. The reason for this observation is unknown. The objective of this study was to calculate the forces of all three hamstring muscles, relative to each other, during a lengthening contraction to assess for any differences that may help explain the biceps femoris predilection for injury during interval sprinting. To calculate the displacement of each individual hamstring muscle previously performed studies on cadaveric anatomical data and hamstring kinematics during sprinting were used. From these displacement calculations for each individual hamstring muscle physical principles were then used to deduce the proportion of force exerted by each individual hamstring muscle during a lengthening muscle contraction. These deductions demonstrate that the biceps femoris muscle is required to exert proportionally more force in a lengthening muscle contraction relative to the semimembranosus and semitendinosus muscles primarily as a consequence of having to lengthen over a greater distance within the same time frame. It is hypothesized that this property maybe a factor in the known observation of the increased susceptibility of the biceps femoris muscle to injury during repeated sprints where recurrent higher force is required. PMID:25506583

  9. Stiff muscle fibers in calf muscles of patients with cerebral palsy lead to high passive muscle stiffness.

    PubMed

    Mathewson, Margie A; Chambers, Henry G; Girard, Paul J; Tenenhaus, Mayer; Schwartz, Alexandra K; Lieber, Richard L

    2014-12-01

    Cerebral palsy (CP), caused by an injury to the developing brain, can lead to alterations in muscle function. Subsequently, increased muscle stiffness and decreased joint range of motion are often seen in patients with CP. We examined mechanical and biochemical properties of the gastrocnemius and soleus muscles, which are involved in equinus muscle contracture. Passive mechanical testing of single muscle fibers from gastrocnemius and soleus muscle of patients with CP undergoing surgery for equinus deformity showed a significant increase in fiber stiffness (p<0.01). Bundles of fibers that included their surrounding connective tissues showed no stiffness difference (p=0.28).). When in vivo sarcomere lengths were measured and fiber and bundle stiffness compared at these lengths, both fibers and bundles of patients with CP were predicted to be much stiffer in vivo compared to typically developing (TD) individuals. Interestingly, differences in fiber and bundle stiffness were not explained by typical biochemical measures such as titin molecular weight (a giant protein thought to impact fiber stiffness) or collagen content (a proxy for extracellular matrix amount). We suggest that the passive mechanical properties of fibers and bundles are thus poorly understood. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  10. Human skeletal muscle fibroblasts stimulate in vitro myogenesis and in vivo muscle regeneration.

    PubMed

    Mackey, Abigail L; Magnan, Mélanie; Chazaud, Bénédicte; Kjaer, Michael

    2017-08-01

    Accumulation of skeletal muscle extracellular matrix is an unfavourable characteristic of many muscle diseases, muscle injury and sarcopenia. The extent of cross-talk between fibroblasts, as the source of matrix protein, and satellite cells in humans is unknown. We studied this in human muscle biopsies and cell-culture studies. We observed a strong stimulation of myogenesis by human fibroblasts in cell culture. In biopsies collected 30 days after a muscle injury protocol, fibroblast number increased to four times control levels, where fibroblasts were found to be preferentially located immediately surrounding regenerating muscle fibres. These novel findings indicate an important role for fibroblasts in supporting the regeneration of muscle fibres, potentially through direct stimulation of satellite cell differentiation and fusion, and contribute to understanding of cell-cell cross-talk during physiological and pathological muscle remodelling. Accumulation of skeletal muscle extracellular matrix is an unfavourable characteristic of many muscle diseases, muscle injury and sarcopenia. In addition to the indispensable role satellite cells play in muscle regeneration, there is emerging evidence in rodents for a regulatory influence on fibroblast activity. However, the influence of fibroblasts on satellite cells and muscle regeneration in humans is unknown. The purpose of this study was to investigate this in vitro and during in vivo regeneration in humans. Following a muscle injury protocol in young healthy men (n = 7), the number of fibroblasts (TCF7L2+), satellite cells (Pax7+), differentiating myogenic cells (myogenin+) and regenerating fibres (neonatal/embryonic myosin+) was determined from biopsy cross-sections. Fibroblasts and myogenic precursor cells (MPCs) were also isolated from human skeletal muscle (n = 4) and co-cultured using different cell ratios, with the two cell populations either in direct contact with each other or separated by a permeable

  11. Sonic hedgehog acts cell-autonomously on muscle precursor cells to generate limb muscle diversity

    PubMed Central

    Anderson, Claire; Williams, Victoria C.; Moyon, Benjamin; Daubas, Philippe; Tajbakhsh, Shahragim; Buckingham, Margaret E.; Shiroishi, Toshihiko; Hughes, Simon M.; Borycki, Anne-Gaëlle

    2012-01-01

    How muscle diversity is generated in the vertebrate body is poorly understood. In the limb, dorsal and ventral muscle masses constitute the first myogenic diversification, as each gives rise to distinct muscles. Myogenesis initiates after muscle precursor cells (MPCs) have migrated from the somites to the limb bud and populated the prospective muscle masses. Here, we show that Sonic hedgehog (Shh) from the zone of polarizing activity (ZPA) drives myogenesis specifically within the ventral muscle mass. Shh directly induces ventral MPCs to initiate Myf5 transcription and myogenesis through essential Gli-binding sites located in the Myf5 limb enhancer. In the absence of Shh signaling, myogenesis is delayed, MPCs fail to migrate distally, and ventral paw muscles fail to form. Thus, Shh production in the limb ZPA is essential for the spatiotemporal control of myogenesis and coordinates muscle and skeletal development by acting directly to regulate the formation of specific ventral muscles. PMID:22987640

  12. Integrated expression analysis of muscle hypertrophy identifies Asb2 as a negative regulator of muscle mass

    PubMed Central

    Davey, Jonathan R.; Watt, Kevin I.; Parker, Benjamin L.; Chaudhuri, Rima; Ryall, James G.; Cunningham, Louise; Qian, Hongwei; Sartorelli, Vittorio; Chamberlain, Jeffrey; James, David E.

    2016-01-01

    The transforming growth factor-β (TGF-β) signaling network is a critical regulator of skeletal muscle mass and function and, thus, is an attractive therapeutic target for combating muscle disease, but the underlying mechanisms of action remain undetermined. We report that follistatin-based interventions (which modulate TGF-β network activity) can promote muscle hypertrophy that ameliorates aging-associated muscle wasting. However, the muscles of old sarcopenic mice demonstrate reduced response to follistatin compared with healthy young-adult musculature. Quantitative proteomic and transcriptomic analyses of young-adult muscles identified a transcription/translation signature elicited by follistatin exposure, which included repression of ankyrin repeat and SOCS box protein 2 (Asb2). Increasing expression of ASB2 reduced muscle mass, thereby demonstrating that Asb2 is a TGF-β network–responsive negative regulator of muscle mass. In contrast to young-adult muscles, sarcopenic muscles do not exhibit reduced ASB2 abundance with follistatin exposure. Moreover, preventing repression of ASB2 in young-adult muscles diminished follistatin-induced muscle hypertrophy. These findings provide insight into the program of transcription and translation events governing follistatin-mediated adaptation of skeletal muscle attributes and identify Asb2 as a regulator of muscle mass implicated in the potential mechanistic dysfunction between follistatin-mediated muscle growth in young and old muscles. PMID:27182554

  13. Functional morphology and comparative anatomy of appendicular musculature in Cuban Anolis lizards with different locomotor habits.

    PubMed

    Anzai, Wataru; Omura, Ayano; Diaz, Antonio Cadiz; Kawata, Masakado; Endo, Hideki

    2014-07-01

    We examined the diversity of the musculoskeletal morphology in the limbs of Anolis lizards with different habitats and identified variations in functional and morphological adaptations to different ecologies or behaviors. Dissection and isolation of 40 muscles from the fore- and hindlimbs of five species of Anolis were performed, and the muscle mass and length of the moment arm were compared after body size effects were removed. Ecologically and behaviorally characteristic morphological differences were observed in several muscles. Well-developed hindlimb extensors were observed in ground-dwelling species, A. sagrei and A. bremeri, and were considered advantageous for running, whereas adept climber species possessed expanded femoral retractors for weight-bearing during climbing. Moreover, morphological variations were observed among arboreal species. Wider excursions of the forelimb joint characterized A. porcatus, presumably enabling branch-to-branch locomotion, while A. equestris and A. angusticeps possessed highly developed adductor muscles for grasping thick branches or twigs. These findings suggest divergent evolution of musculoskeletal characteristic in the limbs within the genus Anolis, with correlations observed among morphological traits, locomotor performance, and habitat uses.

  14. Control of FES thumb force using slip information obtained from the cutaneous electroneurogram in quadriplegic man.

    PubMed

    Haugland, M; Lickel, A; Haase, J; Sinkjaer, T

    1999-06-01

    A tetraplegic volunteer was implanted with percutaneous intramuscular electrodes in hand and forearm muscles. Furthermore, a sensory nerve cuff electrode was implanted on the volar digital nerve to the radial side of the index finger branching off the median nerve. In laboratory experiments a stimulation system was used to produce a lateral grasp (key grip) while the neural activity was recorded with the cuff electrode. The nerve signal contained information that could be used to detect the occurrence of slips and further to increase stimulation intensity to the thumb flexor/adductor muscles to stop the slip. Thereby the system provided a grasp that could catch an object if it started to slip due to, e.g., decreasing muscle force or changes in load forces tangential to the surface of the object. This method enabled an automatic adjustment of the stimulation intensity to the lowest possible level without loosing the grip and without any prior knowledge about the strength of the muscles and the weight and surface texture of the object.

  15. Reliability of handheld dynamometry in assessment of hip strength in adult male football players.

    PubMed

    Fulcher, Mark L; Hanna, Chris M; Raina Elley, C

    2010-01-01

    The aim of this study was to evaluate the intra- and interrater reliability of handheld dynamometry (HHD) for measuring hip muscle strength in a sample of 30 healthy semi-professional adult male football players. The reliability of HHD had not been assessed in athletes who were likely to be stronger than populations tested previously. Maximal isometric strength of resisted hip flexion and adduction were measured. Mean strength ranged from 51.5 kg for dominant hip flexion to 26.7 kg for hip adduction at 90 degrees of hip flexion. Intrarater reliability intraclass correlation coefficients (ICCs) ranged from 0.70 to 0.89. ICCs for interrater reliability ranged from 0.66 to 0.87. As expected, muscle strength in this group of athletes was significantly higher than that of populations in which HHD reliability has been assessed. Despite this, muscle strength testing of hip flexor and adductor muscles can be performed with good to excellent intra- and interrater reliability in this population. Copyright (c) 2009. Published by Elsevier Ltd.

  16. Role of muscle spindle in weightlessness-induced amyotrophia and muscle pain.

    PubMed

    Ali, Umar; Fan, Xiao-Li; You, Hao-Jun

    2009-10-01

    To date, the medium and long-term space flight is urgent in need and has become a major task of our manned space flight program. There is no doubt that medium and long-term space flight has serious damaging impact upon human physiological systems. For instance, atrophy of the lower limb anti-gravity muscle can be induced during the space flight. Muscle atrophy significantly affects the flight of astronauts in space. Most importantly, it influences the precise manipulation of the astronauts and their response capacity to emergencies on returning to the atmosphere from space. Muscle atrophy caused by weightlessness may also seriously disrupt the normal life and work of the astronauts during the re-adaptation period. Here we summarize the corresponding research concentrating on weightlessness-induced changes of muscular structure and function. By combining research on muscle pain, which is a common clinical pain disease, we further provide a hypothesis concerning a dynamic feedback model of "weightlessness condition right triple arrow muscular atrophy <--> muscle pain". This may be useful to explore the neural mechanisms underlying the occurrence and development of muscular atrophy and muscle pain, through the key study of muscle spindle, and furthermore provide more effective therapy for clinical treatment.

  17. Muscle twitching

    MedlinePlus

    ... Some are common and normal. Others are signs of a nervous system disorder. Causes Causes may include: Autoimmune disorders , such ... muscle Spinal muscular atrophy Weak muscles (myopathy) Symptoms of a nervous system disorder include: Loss of, or change in, sensation ...

  18. Ultrasound assessment of hamstring muscle size using posterior thigh muscle thickness.

    PubMed

    Abe, Takashi; Loenneke, Jeremy P; Thiebaud, Robert S

    2016-05-01

    Several studies have investigated the relationship between ultrasound-measured muscle thickness (MT) and individual muscle cross-sectional area (CSA) and muscle volume (MV) in extremity and trunk muscles; however, the hamstring muscle has not been studied. The purpose of this study was to examine the relationship between posterior thigh MT by ultrasound and the muscle CSA and MV of the hamstring obtained by magnetic resonance imaging (MRI). Ten young women aged 20-31 had MT measured by ultrasound at three sites on the medial anterior (50% of thigh length; TL) and posterior (50% and 70% of TL) aspects of the thigh. On the same day, a series of continuous muscle CSA along the thigh was measured by MRI. In each slice, the anatomical CSA of the hamstring (biceps femoris, semitendinosus and semimembranosus) and quadriceps muscle was analysed, and the CSAs at 50% and 70% of TL and maximal CSA of the hamstring (CSAmax ) were determined. MV was calculated by multiplying CSA by slice thickness. A significant correlation was observed between posterior 50% MT and 50% hamstring CSA (r = 0·848, P = 0·002) and between posterior 70% MT and 70% hamstring CSA (r = 0·679, P = 0·031). Posterior 50% MT (r = 0·732, P = 0·016) and 50% MTxTL (r = 0·873, P = 0·001) were also correlated to hamstring MV. Anterior:posterior 50% thigh MT ratio was correlated to MV ratio of quadriceps and hamstring muscles (r = 0·803, P = 0·005). Our results suggest that posterior thigh MT reflects hamstring muscle CSA and MV. The anterior:posterior MT ratio may serve as a surrogate for MV ratio of quadriceps and hamstring. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  19. Differential sensitivity of oxidative and glycolytic muscles to hypoxia-induced muscle atrophy.

    PubMed

    de Theije, C C; Langen, R C J; Lamers, W H; Gosker, H R; Schols, A M W J; Köhler, S E

    2015-01-15

    Hypoxia as a consequence of acute and chronic respiratory disease has been associated with muscle atrophy. This study investigated the sensitivity of oxidative and glycolytic muscles to hypoxia-induced muscle atrophy. Male mice were exposed to 8% normobaric oxygen for up to 21 days. Oxidative soleus and glycolytic extensor digitorum longus (EDL) muscles were isolated, weighed, and assayed for expression profiles of the ubiquitin-proteasome system (UPS), the autophagy-lysosome pathway (ALP), and glucocorticoid receptor (GR) and hypoxia-inducible factor-1α (HIF1α) signaling. Fiber-type composition and the capillary network were investigated. Hypoxia-induced muscle atrophy was more prominent in the EDL than the soleus muscle. Although increased expression of HIF1α target genes showed that both muscle types sensed hypoxia, their adaptive responses differed. Atrophy consistently involved a hypoxia-specific effect (i.e., not attributable to a hypoxia-mediated reduction of food intake) in the EDL only. Hypoxia-specific activation of the UPS and ALP and increased expression of the glucocorticoid receptor (Gr) and its target genes were also mainly observed in the EDL. In the soleus, stimulation of gene expression of those pathways could be mimicked to a large extent by food restriction alone. Hypoxia increased the number of capillary contacts per fiber cross-sectional area in both muscles. In the EDL, this was due to type II fiber atrophy, whereas in the soleus the absolute number of capillary contacts increased. These responses represent two distinct modes to improve oxygen supply to muscle fibers, but may aggravate muscle atrophy in chronic obstructive pulmonary disease patients who have a predominance of type II fibers. Copyright © 2015 the American Physiological Society.

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

    PubMed

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

    2017-12-01

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

  1. The Promotion of a Functional Fibrosis in Skeletal Muscle with Volumetric Muscle Loss Injury Following the Transplantation of Muscle-ECM

    DTIC Science & Technology

    2013-02-04

    i.e., volumetric muscle loss; VML). The explicit goal is to restore functional capacity to the injured tissue by promoting generation of muscle fibers ...3,23,25,27,28]. As a result, trans- plantation of a variety of ECMs in preclinical animal models has resulted in modest levels of muscle fiber generation at...the site of the defect during the initial months post-injury [20,28e30]. However, an apparent enhanced rate of muscle fiber generation at

  2. [Analysis of phonosurgical methods of treatment in spasmodic dysphonia].

    PubMed

    Kosztyła-Hojna, Bożena; Berger, Greta; Zdrojkowski, Maciej

    2017-02-20

    Spasmodic dysphonia (SD) is rather a rare voice disorder. It is most often seen in woman aged 40-50. The disease is caused by deep emotional and neurological disorders of extrapyramidal system. Two main clinical forms of SD are distinguished: about 90% of cases - adductor spasmodic dysphonia and abductor spasmodic dysphonia roughly 10%. Conservative therapy does not always yield sufficient effects. Botulinum toxin - type A injections into the thyroarytenoid muscle are also used in therapy. Though results are temporary and reversible. Among phonosurgical methods thyroplasty type II according to Isshiki and tyroarytenoid muscle myectomy (TAM) should be also mentioned among phonosurgical methods. The aim of the work is to evaluate results of conservative and phonosurgical treatment of SD. Spasmodic dysphonia markedly restricts communication process of patients and public relations both social and occupational.

  3. Lateral Pectoral Nerve Injury Mimicking Cervical Radiculopathy.

    PubMed

    Aktas, Ilknur; Palamar, Deniz; Akgun, Kenan

    2015-07-01

    The lateral pectoral nerve (LPN) is commonly injured along with the brachial plexus, but its isolated lesions are rare. Here, we present a case of an isolated LPN lesion confused with cervical radiculopathy. A 41-year-old man was admitted to our clinic because of weakness in his right arm. Previous magnetic resonance imaging (MRI) examination revealed right posterolateral protrusion at the C6-7 level. At the initial assessment, atrophy of the right pectoralis major muscle was evident, and mild weakness of the right shoulder adductor, internal rotator, and flexor muscles was observed. Therefore, electrodiagnostic evaluation was performed, and a diagnosis of isolated LPN injury was made. Nerve injury was thought to have been caused by weightlifting exercises and traction injury. Lateral pectoral nerve injury can mimic cervical radiculopathy, and MRI examination alone may lead to misdiagnosis. Repeated physical examinations during the evaluation and treatment phase will identify the muscle atrophy that occurs 1 or more months after the injury.

  4. Estimating cranial musculoskeletal constraints in theropod dinosaurs.

    PubMed

    Lautenschlager, Stephan

    2015-11-01

    Many inferences on the biology, behaviour and ecology of extinct vertebrates are based on the reconstruction of the musculature and rely considerably on its accuracy. Although the advent of digital reconstruction techniques has facilitated the creation and testing of musculoskeletal hypotheses in recent years, muscle strain capabilities have rarely been considered. Here, a digital modelling approach using the freely available visualization and animation software Blender is applied to estimate cranial muscle length changes and optimal and maximal possible gape in different theropod dinosaurs. Models of living archosaur taxa (Alligator mississippiensis, Buteo buteo) were used in an extant phylogenetically bracketed framework to validate the method. Results of this study demonstrate that Tyrannosaurus rex, Allosaurus fragilis and Erlikosaurus andrewsi show distinct differences in the recruitment of the jaw adductor musculature and resulting gape, confirming previous dietary and ecological assumptions. While the carnivorous taxa T. rex and Allo. fragilis were capable of a wide gape and sustained muscle force, the herbivorous therizinosaurian E. andrewsi was constrained to small gape angles.

  5. Unilateral Muscle Overuse Causes Bilateral Changes in Muscle Fiber Composition and Vascular Supply

    PubMed Central

    Song, Yafeng; Forsgren, Sture; Liu, Jing-Xia; Yu, Ji-Guo; Stål, Per

    2014-01-01

    Unilateral strength training can cause cross-transfer strength effects to the homologous contralateral muscles. However, the impact of the cross-over effects on the muscle tissue is unclear. To test the hypothesis that unilateral muscle overuse causes bilateral alterations in muscle fiber composition and vascular supply, we have used an experimental rabbit model with unilateral unloaded overstrain exercise via electrical muscle stimulation (E/EMS). The soleus (SOL) and gastrocnemius (GA) muscles of both exercised (E) and contralateral non-exercised (NE) legs (n = 24) were morphologically analyzed after 1w, 3w and 6w of EMS. Non-exercised rabbits served as controls (n = 6). After unilateral intervention the muscles of both E and NE legs showed myositis and structural and molecular tissue changes that to various degrees mirrored each other. The fiber area was bilaterally smaller than in controls after 3w of E/EMS in both SOL (E 4420 and NE 4333 µm2 vs. 5183 µm2, p<0.05) and GA (E 3572 and NE 2983 µm2 vs. 4697 µm2, p<0.02) muscles. After 6w of E/EMS, the percentage of slow MyHCI fibers was lower than in controls in the NE legs of SOL (88.1% vs. 98.1%, p<0.009), while the percentage of fast MyHCIIa fibers was higher in the NE legs of GA (25.7% vs. 15.8%, p = 0.02). The number of capillaries around fibers in the E and NE legs was lower (SOL 13% and 15%, respectively, GA 25% and 23%, respectively, p<0.05) than in controls. The overall alterations were more marked in the fast GA muscle than in the slow SOL muscle, which on the other hand showed more histopathological muscle changes. We conclude that unilateral repetitive unloaded overuse exercise via EMS causes myositis and muscle changes in fiber type proportions, fiber area and fiber capillarization not only in the exercised leg, but also in the homologous muscles in the non-exercised leg. PMID:25545800

  6. Effects of experimental muscle pain on muscle activity and co-ordination during static and dynamic motor function.

    PubMed

    Graven-Nielsen, T; Svensson, P; Arendt-Nielsen, L

    1997-04-01

    The relation between muscle pain, muscle activity, and muscle co-ordination is still controversial. The present human study investigates the influence of experimental muscle pain on resting, static, and dynamic muscle activity. In the resting and static experiments, the electromyography (EMG) activity and the contraction force of m. tibialis anterior were assessed before and after injection of 0.5 ml hypertonic saline (5%) into the same muscle. In the dynamic experiment, injections of 0.5 ml hypertonic saline (5%) were performed into either m. tibialis anterior (TA) or m. gastrocnemius (GA) and the muscle activity and co-ordination were investigated during gait on a treadmill by EMG recordings from m. TA and m. GA. At rest no evidence of EMG hyperactivity was found during muscle pain. The maximal voluntary contraction (MVC) during muscle pain was significantly lower than the control condition (P < 0.05). During a static contraction at 80% of the pre-pain MVC muscle pain caused a significant reduction in endurance time (P < 0.043). During dynamic contractions, muscle pain resulted in a significant decrease of the EMG activity in the muscle, agonistic to the painful muscle (P < 0.05), and a significant increase of the EMG activity of the muscle, antagonistic to the painful muscle (P < 0.05). Muscle pain seems to cause a general protection of painful muscles during both static and dynamic contractions. The increased EMG activity of the muscle antagonistic to the painful muscle is probably a functional adaptation of muscle co-ordination in order to limit movements. Modulation of muscle activity by muscle pain could be controlled via inhibition of muscles agonistic to the movement and/or excitation of muscles antagonistic to the movement. The present results are in accordance with the pain-adaptation model (Lund, J.P., Stohler, C.S. and Widmer, C.G. In: H. Vaerøy and H. Merskey (Eds.), Progress in Fibromyalgia and Myofascial Pain. Elsevier, Amsterdam, 1993, pp. 311

  7. Muscle fatigue in fibromyalgia is in the brain, not in the muscles: a case-control study of perceived versus objective muscle fatigue.

    PubMed

    Bandak, Elisabeth; Amris, Kirstine; Bliddal, Henning; Danneskiold-Samsøe, Bente; Henriksen, Marius

    2013-06-01

    To investigate relationships between perceived and objectively measured muscle fatigue during exhausting muscle contractions in women with fibromyalgia (FM) compared with healthy controls (HC). Women with FM and HC completed an isometric muscle exhaustion task at 90° shoulder abduction. Surface electromyographic (EMG) activity in the deltoid muscle was recorded together with self-reported level of muscle fatigue. 25 participants with FM and 23 HC were included. Average time to exhaustion was 254 s shorter in participants with FM than in HC. Participants with FM did not exhibit the same level of objective signs of muscle fatigue, seen as fewer changes in the EMG activity, as the HC during the exhaustion task. The task did not provoke pain in the HC, while participants with FM reported a doubling of pain. Women with FM had shorter exhaustion times and showed fewer objective signs of muscle fatigue during an exhausting isometric shoulder abduction compared with younger HC. This indicates that perceived muscle fatigue may be of central origin and supports the notion of central nervous dysfunction as basic pathological changes in FM.

  8. Functional recovery of completely denervated muscle: implications for innervation of tissue-engineered muscle.

    PubMed

    Kang, Sung-Bum; Olson, Jennifer L; Atala, Anthony; Yoo, James J

    2012-09-01

    Tissue-engineered muscle has been proposed as a solution to repair volumetric muscle defects and to restore muscle function. To achieve functional recovery, engineered muscle tissue requires integration of the host nerve. In this study, we investigated whether denervated muscle, which is analogous to tissue-engineered muscle tissue, can be reinnervated and can recover muscle function using an in vivo model of denervation followed by neurotization. The outcomes of this investigation may provide insights on the ability of tissue-engineered muscle to integrate with the host nerve and acquire normal muscle function. Eighty Lewis rats were classified into three groups: a normal control group (n=16); a denervated group in which sciatic innervations to the gastrocnemius muscle were disrupted (n=32); and a transplantation group in which the denervated gastrocnemius was repaired with a common peroneal nerve graft into the muscle (n=32). Neurofunctional behavior, including extensor postural thrust (EPT), withdrawal reflex latency (WRL), and compound muscle action potential (CMAP), as well as histological evaluations using alpha-bungarotoxin and anti-NF-200 were performed at 2, 4, 8, and 12 weeks (n=8) after surgery. We found that EPT was improved by transplantation of the nerve grafts, but the EPT values in the transplanted animals at 12 weeks postsurgery were still significantly lower than those measured for the normal control group at 4 weeks (EPT, 155.0±38.9 vs. 26.3±13.8 g, p<0.001; WRL, 2.7±2.30 vs. 8.3±5.5 s, p=0.027). In addition, CMAP latency and amplitude significantly improved with time after surgery in the transplantation group (p<0.001, one-way analysis of variance), and at 12 weeks postsurgery, CMAP latency and amplitude were not statistically different from normal control values (latency, 0.9±0.0 vs. 1.3±0.7 ms, p=0.164; amplitude, 30.2±7.0 vs. 46.4±26.9 mV, p=0.184). Histologically, regeneration of neuromuscular junctions was seen in the

  9. Re-positioning forelimb superficialis muscles: tendon attachment and muscle activity enable active relocation of functional myofibers

    PubMed Central

    Huang, Alice H.; Riordan, Timothy J.; Wang, Lingyan; Eyal, Shai; Zelzer, Elazar; Brigande, John V.; Schweitzer, Ronen

    2013-01-01

    Summary The muscles that govern hand motion are composed of extrinsic muscles that reside within the forearm and intrinsic muscles that reside within the hand. We find that the extrinsic muscles of the flexor digitorum superficialis (FDS) first differentiate as intrinsic muscles within the hand and then relocate as myofibers to their final position in the arm. This unique translocation of differentiated myofibers across a joint is dependent on muscle contraction and muscle-tendon attachment. Interestingly, the intrinsic flexor digitorum brevis (FDB) muscles of the foot are identical to the FDS in tendon pattern and delayed developmental timing, but undergo limited muscle translocation, providing strong support for evolutionary homology between the FDS and FDB muscles. We propose that the intrinsic FDB pattern represents the original tetrapod limb and translocation of the muscles to form the FDS is a mammalian evolutionary addition. PMID:24044893

  10. Electromyographic evaluation of abdominal-muscle function with and without concomitant pelvic-floor-muscle contraction.

    PubMed

    Tahan, Nahid; Arab, Amir Massoud; Vaseghi, Bita; Khademi, Khosro

    2013-05-01

    Coactivation of abdominal and pelvic-floor muscles (PFM) is an issue considered by researchers recently. Electromyography (EMG) studies have shown that the abdominal-muscle activity is a normal response to PFM activity, and increase in EMG activity of the PFM concomitant with abdominal-muscle contraction was also reported. The purpose of this study was to compare the changes in EMG activity of the deep abdominal muscles during abdominal-muscle contraction (abdominal hollowing and bracing) with and without concomitant PFM contraction in healthy and low-back-pain (LBP) subjects. A 2 × 2 repeated-measures design. Laboratory. 30 subjects (15 with LBP, 15 without LBP). Peak rectified EMG of abdominal muscles. No difference in EMG of abdominal muscles with and without concomitant PFM contraction in abdominal hollowing (P = .84) and abdominal bracing (P = .53). No difference in EMG signal of abdominal muscles with and without PFM contraction between LBP and healthy subjects in both abdominal hollowing (P = .88) and abdominal bracing (P = .98) maneuvers. Adding PFM contraction had no significant effect on abdominal-muscle contraction in subjects with and without LBP.

  11. Muscle abnormalities in osteogenesis imperfecta

    PubMed Central

    Veilleux, L-N.; Trejo, P.; Rauch, F.

    2017-01-01

    Osteogenesis imperfecta (OI) is mainly characterized by bone fragility but muscle abnormalities have been reported both in OI mouse models and in children with OI. Muscle mass is decreased in OI, even when short stature is taken into account. Dynamic muscle tests aiming at maximal eccentric force production reveal functional deficits that can not be explained by low muscle mass alone. However, it appears that diaphyseal bone mass is normally adapted to muscle force. At present the determinants of muscle mass and function in OI have not been clearly defined. Physiotherapy interventions and bisphosphonate treatment appear to have some effect on muscle function in OI. Interventions targeting muscle mass have shown encouraging results in OI animal models and are an interesting area for further research. PMID:28574406

  12. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    NASA Astrophysics Data System (ADS)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-07-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature ( P < 0.05). This result indicated that repeated local muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  13. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans.

    PubMed

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-07-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature (P < 0.05). This result indicated that repeated local muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  14. Biomimetic Scaffolds for Regeneration of Volumetric Muscle Loss in Skeletal Muscle Injuries

    PubMed Central

    Grasman, Jonathan M.; Zayas, Michelle J.; Page, Ray; Pins, George D.

    2015-01-01

    Skeletal muscle injuries typically result from traumatic incidents such as combat injuries where soft-tissue extremity injuries are present in one of four cases. Further, about 4.5 million reconstructive surgical procedures are performed annually as a result of car accidents, cancer ablation, or cosmetic procedures. These combat- and trauma-induced skeletal muscle injuries are characterized by volumetric muscle loss (VML), which significantly reduces the functionality of the injured muscle. While skeletal muscle has an innate repair mechanism, it is unable to compensate for VML injuries because large amounts of tissue including connective tissue and basement membrane are removed or destroyed. This results in in a significant need to develop off-the-shelf biomimetic scaffolds to direct skeletal muscle regeneration. Here, the structure and organization of native skeletal muscle tissue is described in order to reveal clear design parameters that are necessary for scaffolds to mimic in order to successfully regenerate muscular tissue. We review the literature with respect to the materials and methodologies used to develop scaffolds for skeletal muscle tissue regeneration as well as the limitations of these materials. We further discuss the variety of cell sources and different injury models to provide some context for the multiple approaches used to evaluate these scaffold materials. Recent findings are highlighted to address the state of the field and directions are outlined for future strategies, both in scaffold design and in the use of different injury models to evaluate these materials, for regenerating functional skeletal muscle. PMID:26219862

  15. Ischemia causes muscle fatigue

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D. M.

    2001-01-01

    The purpose of this investigation was to determine whether ischemia, which reduces oxygenation in the extensor carpi radialis (ECR) muscle, causes a reduction in muscle force production. In eight subjects, muscle oxygenation (TO2) of the right ECR was measured noninvasively and continuously using near infrared spectroscopy (NIRS) while muscle twitch force was elicited by transcutaneous electrical stimulation (1 Hz, 0.1 ms). Baseline measurements of blood volume, muscle oxygenation and twitch force were recorded continuously, then a tourniquet on the upper arm was inflated to one of five different pressure levels: 20, 40, 60 mm Hg (randomized order) and diastolic (69 +/- 9.8 mm Hg) and systolic (106 +/- 12.8 mm Hg) blood pressures. Each pressure level was maintained for 3-5 min, and was followed by a recovery period sufficient to allow measurements to return to baseline. For each respective tourniquet pressure level, mean TO2 decreased from resting baseline (100% TO2) to 99 +/- 1.2% (SEM), 96 +/- 1.9%, 93 +/- 2.8%, 90 +/- 2.5%, and 86 +/- 2.7%, and mean twitch force decreased from resting baseline (100% force) to 99 +/- 0.7% (SEM), 96 +/- 2.7%, 93 +/- 3.1%, 88 +/- 3.2%, and 86 +/- 2.6%. Muscle oxygenation and twitch force at 60 mm Hg tourniquet compression and above were significantly lower (P < 0.05) than baseline value. Reduced twitch force was correlated in a dose-dependent manner with reduced muscle oxygenation (r = 0.78, P < 0.001). Although the correlation does not prove causation, the results indicate that ischemia leading to a 7% or greater reduction in muscle oxygenation causes decreased muscle force production in the forearm extensor muscle. Thus, ischemia associated with a modest decline in TO2 causes muscle fatigue.

  16. Respiratory muscle involvement in sarcoidosis.

    PubMed

    Schreiber, Tina; Windisch, Wolfram

    2018-07-01

    In sarcoidosis, muscle involvement is common, but mostly asymptomatic. Currently, little is known about respiratory muscle and diaphragm involvement and function in patients with sarcoidosis. Reduced inspiratory muscle strength and/or a reduced diaphragm function may contribute to exertional dyspnea, fatigue and reduced health-related quality of life. Previous studies using volitional and non-volitional tests demonstrated a reduced inspiratory muscle strength in sarcoidosis compared to control subjects, and also showed that respiratory muscle function may even be significantly impaired in a subset of patients. Areas covered: This review examines the evidence on respiratory muscle involvement and its implications in sarcoidosis with emphasis on pathogenesis, diagnosis and treatment of respiratory muscle dysfunction. The presented evidence was identified by a literature search performed in PubMed and Medline for articles about respiratory and skeletal muscle function in sarcoidosis through to January 2018. Expert commentary: Respiratory muscle involvement in sarcoidosis is an underdiagnosed condition, which may have an important impact on dyspnea and health-related quality of life. Further studies are needed to understand the etiology, pathogenesis and extent of respiratory muscle involvement in sarcoidosis.

  17. Effect of altering starting length and activation timing of muscle on fiber strain and muscle damage.

    PubMed

    Butterfield, Timothy A; Herzog, Walter

    2006-05-01

    Muscle strain injuries are some of the most frequent injuries in sports and command a great deal of attention in an effort to understand their etiology. These injuries may be the culmination of a series of subcellular events accumulated through repetitive lengthening (eccentric) contractions during exercise, and they may be influenced by a variety of variables including fiber strain magnitude, peak joint torque, and starting muscle length. To assess the influence of these variables on muscle injury magnitude in vivo, we measured fiber dynamics and joint torque production during repeated stretch-shortening cycles in the rabbit tibialis anterior muscle, at short and long muscle lengths, while varying the timing of activation before muscle stretch. We found that a muscle subjected to repeated stretch-shortening cycles of constant muscle-tendon unit excursion exhibits significantly different joint torque and fiber strains when the timing of activation or starting muscle length is changed. In particular, measures of fiber strain and muscle injury were significantly increased by altering activation timing and increasing the starting length of the muscle. However, we observed differential effects on peak joint torque during the cyclic stretch-shortening exercise, as increasing the starting length of the muscle did not increase torque production. We conclude that altering activation timing and muscle length before stretch may influence muscle injury by significantly increasing fiber strain magnitude and that fiber dynamics is a more important variable than muscle-tendon unit dynamics and torque production in influencing the magnitude of muscle injury.

  18. Potential of laryngeal muscle regeneration using induced pluripotent stem cell-derived skeletal muscle cells.

    PubMed

    Dirja, Bayu Tirta; Yoshie, Susumu; Ikeda, Masakazu; Imaizumi, Mitsuyoshi; Nakamura, Ryosuke; Otsuki, Koshi; Nomoto, Yukio; Wada, Ikuo; Hazama, Akihiro; Omori, Koichi

    2016-01-01

    Conclusion Induced pluripotent stem (iPS) cells may be a new potential cell source for laryngeal muscle regeneration in the treatment of vocal fold atrophy after recurrent laryngeal nerve paralysis. Objectives Unilateral vocal fold paralysis can lead to degeneration, atrophy, and loss of force of the thyroarytenoid muscle. At present, there are some treatments such as thyroplasty, arytenoid adduction, and vocal fold injection. However, such treatments cannot restore reduced mass of the thyroarytenoid muscle. iPS cells have been recognized as supplying a potential resource for cell transplantation. The aim of this study was to assess the effectiveness of the use of iPS cells for the regeneration of laryngeal muscle through the evaluation of both in vitro and in vivo experiments. Methods Skeletal muscle cells were generated from tdTomato-labeled iPS cells using embryoid body formation. Differentiation into skeletal muscle cells was analyzed by gene expression and immunocytochemistry. The tdTomato-labeled iPS cell-derived skeletal muscle cells were transplanted into the left atrophied thyroarytenoid muscle. To evaluate the engraftment of these cells after transplantation, immunohistochemistry was performed. Results The tdTomato-labeled iPS cells were successfully differentiated into skeletal muscle cells through an in vitro experiment. These cells survived in the atrophied thyroarytenoid muscle after transplantation.

  19. Catechins activate muscle stem cells by Myf5 induction and stimulate muscle regeneration.

    PubMed

    Kim, A Rum; Kim, Kyung Min; Byun, Mi Ran; Hwang, Jun-Ha; Park, Jung Il; Oh, Ho Taek; Kim, Hyo Kyeong; Jeong, Mi Gyeong; Hwang, Eun Sook; Hong, Jeong-Ho

    2017-07-22

    Muscle weakness is one of the most common symptoms in aged individuals and increases risk of mortality. Thus, maintenance of muscle mass is important for inhibiting aging. In this study, we investigated the effect of catechins, polyphenol compounds in green tea, on muscle regeneration. We found that (-)-epicatechin gallate (ECG) and (-)-epigallocatechin-3-gallate (EGCG) activate satellite cells by induction of Myf5 transcription factors. For satellite cell activation, Akt kinase was significantly induced after ECG treatment and ECG-induced satellite cell activation was blocked in the presence of Akt inhibitor. ECG also promotes myogenic differentiation through the induction of myogenic markers, including Myogenin and Muscle creatine kinase (MCK), in satellite and C2C12 myoblast cells. Finally, EGCG administration to mice significantly increased muscle fiber size for regeneration. Taken together, the results suggest that catechins stimulate muscle stem cell activation and differentiation for muscle regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Differences in muscle sympathetic nerve response to isometric exercise in different muscle groups.

    PubMed

    Saito, M

    1995-01-01

    The aim of this study was to examine the effects of muscle fibre composition on muscle sympathetic nerve activity (MSNA) in response to isometric exercise. The MSNA, recorded from the tibial nerve by a microneurographic technique during contraction and following arterial occlusion, was compared in three different muscle groups: the forearm (handgrip), anterior tibialis (foot dorsal contraction), and soleus muscles (foot plantar contraction) contracted separately at intensities of 20%, 33% and 50% of the maximal voluntary force. The increases in MSNA relative to control levels during contraction and occlusion were significant at all contracting forces for handgrip and at 33% and 50% of maximal for dorsal contraction, but there were no significant changes, except during exercise at 50%, for plantar contraction. The size of the MSNA response correlated with the contraction force in all muscle groups. Pooling data for all contraction forces, there were different MSNA responses among muscle groups in contraction forces (P = 0.0001, two-way analysis of variance), and occlusion periods (P = 0.0001). The MSNA increases were in the following order of magnitude: handgrip, dorsal, and plantar contractions. The order of the fibre type composition in these three muscles is from equal numbers of types I and II fibres in the forearm to increasing number of type I fibres in the leg muscles. The different MSNA responses to the contraction of different muscle groups observed may have been due in part to muscle metaboreflex intensity influenced by their metabolic capacity which is related to by their metabolic capacity which is related to the fibre type.

  1. Eccentric muscle challenge shows osteopontin polymorphism modulation of muscle damage.

    PubMed

    Barfield, Whitney L; Uaesoontrachoon, Kitipong; Wu, Chung-Sheih; Lin, Stephen; Chen, Yue; Wang, Paul C; Kanaan, Yasmine; Bond, Vernon; Hoffman, Eric P

    2014-08-01

    A promoter polymorphism of the osteopontin (OPN) gene (rs28357094) has been associated with multiple inflammatory states, severity of Duchenne muscular dystrophy (DMD) and muscle size in healthy young adults. We sought to define the mechanism of action of the polymorphism, using allele-specific in vitro reporter assays in muscle cells, and a genotype-stratified intervention in healthy controls. In vitro reporter constructs showed the G allele to respond to estrogen treatment, whereas the T allele showed no transcriptional response. Young adult volunteers (n = 187) were enrolled into a baseline study, and subjects with specific rs28357094 genotypes enrolled into an eccentric muscle challenge intervention [n = 3 TT; n = 3 GG/GT (dominant inheritance model)]. Female volunteers carrying the G allele showed significantly greater inflammation and increased muscle volume change as determined by magnetic resonance imaging T1- and T2-weighted images after eccentric challenge, as well as greater decrement in biceps muscle force. Our data suggest a model where the G allele enables enhanced activities of upstream enhancer elements due to loss of Sp1 binding at the polymorphic site. This results in significantly greater expression of the pro-inflammatory OPN cytokine during tissue remodeling in response to challenge in G allele carriers, promoting muscle hypertrophy in normal females, but increased damage in DMD patients. © The Author 2014. Published by Oxford University Press.

  2. Your Muscles

    MedlinePlus

    ... and you need to throw up. The muscles push the food back out of the stomach so it comes up ... body the power it needs to lift and push things. Muscles in your neck and the top part of your back aren't as large, but they are capable ...

  3. Brain and muscle Arnt-like 1 promotes skeletal muscle regeneration through satellite cell expansion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chatterjee, Somik; Yin, Hongshan; Department of Cardiovascular Medicine, Third Affiliated Hospital, Hebei Medical University, Shijiazhuang 050051, Hebei

    Circadian clock is an evolutionarily conserved timing mechanism governing diverse biological processes and the skeletal muscle possesses intrinsic functional clocks. Interestingly, although the essential clock transcription activator, Brain and muscle Arnt-like 1 (Bmal1), participates in maintenance of muscle mass, little is known regarding its role in muscle growth and repair. In this report, we investigate the in vivo function of Bmal1 in skeletal muscle regeneration using two muscle injury models. Bmal1 is highly up-regulated by cardiotoxin injury, and its genetic ablation significantly impairs regeneration with markedly suppressed new myofiber formation and attenuated myogenic induction. A similarly defective regenerative response ismore » observed in Bmal1-null mice as compared to wild-type controls upon freeze injury. Lack of satellite cell expansion accounts for the regeneration defect, as Bmal1{sup −/−} mice display significantly lower satellite cell number with nearly abolished induction of the satellite cell marker, Pax7. Furthermore, satellite cell-derived primary myoblasts devoid of Bmal1 display reduced growth and proliferation ex vivo. Collectively, our results demonstrate, for the first time, that Bmal1 is an integral component of the pro-myogenic response that is required for muscle repair. This mechanism may underlie its role in preserving adult muscle mass and could be targeted therapeutically to prevent muscle-wasting diseases. - Highlights: • Bmal1 is highly inducible by muscle injury and myogenic stimuli. • Genetic ablation of Bmal1 significantly impairs muscle regeneration. • Bmal1 promotes satellite cell expansion during muscle regeneration. • Bmal1-deficient primary myoblasts display attenuated growth and proliferation.« less

  4. Association of low back pain with muscle stiffness and muscle mass of the lumbar back muscles, and sagittal spinal alignment in young and middle-aged medical workers.

    PubMed

    Masaki, Mitsuhiro; Aoyama, Tomoki; Murakami, Takashi; Yanase, Ko; Ji, Xiang; Tateuchi, Hiroshige; Ichihashi, Noriaki

    2017-11-01

    Muscle stiffness of the lumbar back muscles in low back pain (LBP) patients has not been clearly elucidated because quantitative assessment of the stiffness of individual muscles was conventionally difficult. This study aimed to examine the association of LBP with muscle stiffness assessed using ultrasonic shear wave elastography (SWE) and muscle mass of the lumbar back muscle, and spinal alignment in young and middle-aged medical workers. The study comprised 23 asymptomatic medical workers [control (CTR) group] and 9 medical workers with LBP (LBP group). Muscle stiffness and mass of the lumbar back muscles (lumbar erector spinae, multifidus, and quadratus lumborum) in the prone position were measured using ultrasonic SWE. Sagittal spinal alignment in the standing and prone positions was measured using a Spinal Mouse. The association with LBP was investigated by multiple logistic regression analysis with a forward selection method. The analysis was conducted using the shear elastic modulus and muscle thickness of the lumbar back muscles, and spinal alignment, age, body height, body weight, and sex as independent variables. Multiple logistic regression analysis showed that muscle stiffness of the lumbar multifidus muscle and body height were significant and independent determinants of LBP, but that muscle mass and spinal alignment were not. Muscle stiffness of the lumbar multifidus muscle in the LBP group was significantly higher than that in the CTR group. The results of this study suggest that LBP is associated with muscle stiffness of the lumbar multifidus muscle in young and middle-aged medical workers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Muscles within muscles: a tensiomyographic and histochemical analysis of the normal human vastus medialis longus and vastus medialis obliquus muscles

    PubMed Central

    Travnik, Ludvik; Djordjevič, Srdjan; Rozman, Sergej; Hribernik, Marija; Dahmane, Raja

    2013-01-01

    The aim of this study was to show the connection between structure (anatomical and histochemical) and function (muscle contraction properties) of vastus medialis obliquus (VMO) and vastus medialis longus (VML). The non-invasive tensiomyography (TMG) method was used to determine the contractile properties (contraction time; Tc) of VML and VMO muscle, as a reflection of the ratio between the slow and fast fibers in two groups of nine young men. VML and VMO significantly (P < 0.01) differ in the proportion of type 1 (59.6: 44%) and type 2b (6.3: 15%) fibers. The VML muscle is almost entirely composed of type 1 and type 2a fibers. In many samples of this muscle no type 2b fibers were found. The proportion of slow-twitch type 1 fibers is nearly twice as high as the proportion of fast-twitch type 2a fibers. These observations indicate that VML is a slower and more fatigue-resistant muscle than VMO muscle. These characteristics correspond to the different functions of the VML, which is an extensor of the knee, and to the VMO, which maintains the stable position of the patella in the femoral groove. Our results obtained by TMG provided additional evidence that muscle fibers within the segments of VM muscle were not homogenous with regard to their contractile properties, thereby confirming the histochemical results. Tc can be attributed to the higher percentage of slow-twitch fibers – type 1. The statistically shorter Tc (P ≤ 0.001) of VMO (22.8 ± 4.0 ms) compared with VML (26.7 ± 4.0 ms) in our study is consistent with previously found differences in histochemical, morphological and electrophysiological data. In conclusion, the results of this study provide evidence that the VML and VMO muscles are not only anatomically and histochemically different muscles, but also functionally different biological structures. PMID:23586984

  6. Effect of Statins on Skeletal Muscle: Exercise, Myopathy, and Muscle Outcomes

    PubMed Central

    Parker, Beth A.; Thompson, Paul D.

    2012-01-01

    Statins are effective for reducing low-density lipoprotein cholesterol and cardiac events, but can produce muscle side effects. We have hypothesized that statin-related muscle complaints are exacerbated by exercise and influenced by factors including mitochondrial dysfunction, membrane disruption and/or calcium handling. The interaction between statins, exercise and muscle symptoms may be more effectively diagnosed and treated as rigorous scientific studies accumulate. PMID:23000957

  7. Exercise-Induced Skeletal Muscle Damage.

    PubMed

    Evans, W J

    1987-01-01

    In brief: Delayed-onset muscle soreness is most likely caused by structural damage in skeletal muscle after eccentric exercise, in which muscles produce force while lengthening, as in running downhill. This damage may take as long as 12 weeks to repair. Therefore, athletes should allow plenty of time for recovery after events that cause extreme muscle soreness. Because prostaglandin E2 may be important in muscle repair, prostaglandin blockers, such as aspirin, may be useless or even detrimental in the treatment of delayed-onset muscle soreness. Eccentric exercise training may help prevent soreness.

  8. Action of obestatin in skeletal muscle repair: stem cell expansion, muscle growth, and microenvironment remodeling.

    PubMed

    Gurriarán-Rodríguez, Uxía; Santos-Zas, Icía; González-Sánchez, Jessica; Beiroa, Daniel; Moresi, Viviana; Mosteiro, Carlos S; Lin, Wei; Viñuela, Juan E; Señarís, José; García-Caballero, Tomás; Casanueva, Felipe F; Nogueiras, Rubén; Gallego, Rosalía; Renaud, Jean-Marc; Adamo, Sergio; Pazos, Yolanda; Camiña, Jesús P

    2015-06-01

    The development of therapeutic strategies for skeletal muscle diseases, such as physical injuries and myopathies, depends on the knowledge of regulatory signals that control the myogenic process. The obestatin/GPR39 system operates as an autocrine signal in the regulation of skeletal myogenesis. Using a mouse model of skeletal muscle regeneration after injury and several cellular strategies, we explored the potential use of obestatin as a therapeutic agent for the treatment of trauma-induced muscle injuries. Our results evidenced that the overexpression of the preproghrelin, and thus obestatin, and GPR39 in skeletal muscle increased regeneration after muscle injury. More importantly, the intramuscular injection of obestatin significantly enhanced muscle regeneration by simulating satellite stem cell expansion as well as myofiber hypertrophy through a kinase hierarchy. Added to the myogenic action, the obestatin administration resulted in an increased expression of vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor 2 (VEGFR2) and the consequent microvascularization, with no effect on collagen deposition in skeletal muscle. Furthermore, the potential inhibition of myostatin during obestatin treatment might contribute to its myogenic action improving muscle growth and regeneration. Overall, our data demonstrate successful improvement of muscle regeneration, indicating obestatin is a potential therapeutic agent for skeletal muscle injury and would benefit other myopathies related to muscle regeneration.

  9. Exercise-induced muscle glucose uptake in mice with graded, muscle-specific GLUT-4 deletion.

    PubMed

    Howlett, Kirsten F; Andrikopoulos, Sofianos; Proietto, Joseph; Hargreaves, Mark

    2013-08-01

    To investigate the importance of the glucose transporter GLUT-4 for muscle glucose uptake during exercise, transgenic mice with skeletal muscle GLUT-4 expression approximately 30-60% of normal (CON) and approximately 5-10% of normal (KO) were generated using the Cre/Lox system and compared with wild-type (WT) mice during approximately 40 min of treadmill running (KO: 37.7 ± 1.3 min; WT: 40 min; CON: 40 min, P = 0.18). In WT and CON animals, exercise resulted in an overall increase in muscle glucose uptake. More specifically, glucose uptake was increased in red gastrocnemius of WT mice and in the soleus and red gastrocnemius of CON mice. In contrast, the exercise-induced increase in muscle glucose uptake in all muscles was completely abolished in KO mice. Muscle glucose uptake increased during exercise in both red and white quadriceps of WT mice, while the small increases in CON mice were not statistically significant. In KO mice, there was no change at all in quadriceps muscle glucose uptake. No differences in muscle glycogen use during exercise were observed between any of the groups. However, there was a significant increase in plasma glucose levels after exercise in KO mice. The results of this study demonstrated that a reduction in skeletal muscle GLUT-4 expression to approximately 10% of normal levels completely abolished the exercise-induced increase in muscle glucose uptake.

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

    USDA-ARS?s Scientific Manuscript database

    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 esta...

  11. Green tea extract attenuates muscle loss and improves muscle function during disuse, but fails to improve muscle recovery following unloading in aged rats

    PubMed Central

    Bennett, Brian T.; Wilson, Joseph C.; Sperringer, Justin; Mohamed, Junaith S.; Edens, Neile K.; Pereira, Suzette L.

    2014-01-01

    In this study we tested the hypothesis that green tea extract (GTE) would improve muscle recovery after reloading following disuse. Aged (32 mo) Fischer 344 Brown Norway rats were randomly assigned to receive either 14 days of hindlimb suspension (HLS) or 14 days of HLS followed by normal ambulatory function for 14 days (recovery). Additional animals served as cage controls. The rats were given GTE (50 mg/kg body wt) or water (vehicle) by gavage 7 days before and throughout the experimental periods. Compared with vehicle treatment, GTE significantly attenuated the loss of hindlimb plantaris muscle mass (−24.8% vs. −10.7%, P < 0.05) and tetanic force (−43.7% vs. −25.9%, P <0.05) during HLS. Although GTE failed to further improve recovery of muscle function or mass compared with vehicle treatment, animals given green tea via gavage maintained the lower losses of muscle mass that were found during HLS (−25.2% vs. −16.0%, P < 0.05) and force (−45.7 vs. −34.4%, P < 0.05) after the reloading periods. In addition, compared with vehicle treatment, GTE attenuated muscle fiber cross-sectional area loss in both plantaris (−39.9% vs. −23.9%, P < 0.05) and soleus (−37.2% vs. −17.6%) muscles after HLS. This green tea-induced difference was not transient but was maintained over the reloading period for plantaris (−45.6% vs. −21.5%, P <0.05) and soleus muscle fiber cross-sectional area (−38.7% vs. −10.9%, P <0.05). GTE increased satellite cell proliferation and differentiation in plantaris and soleus muscles during recovery from HLS compared with vehicle-treated muscles and decreased oxidative stress and abundance of the Bcl-2-associated X protein (Bax), yet this did not further improve muscle recovery in reloaded muscles. These data suggest that muscle recovery following disuse in aging is complex. Although satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is

  12. Green tea extract attenuates muscle loss and improves muscle function during disuse, but fails to improve muscle recovery following unloading in aged rats.

    PubMed

    Alway, Stephen E; Bennett, Brian T; Wilson, Joseph C; Sperringer, Justin; Mohamed, Junaith S; Edens, Neile K; Pereira, Suzette L

    2015-02-01

    In this study we tested the hypothesis that green tea extract (GTE) would improve muscle recovery after reloading following disuse. Aged (32 mo) Fischer 344 Brown Norway rats were randomly assigned to receive either 14 days of hindlimb suspension (HLS) or 14 days of HLS followed by normal ambulatory function for 14 days (recovery). Additional animals served as cage controls. The rats were given GTE (50 mg/kg body wt) or water (vehicle) by gavage 7 days before and throughout the experimental periods. Compared with vehicle treatment, GTE significantly attenuated the loss of hindlimb plantaris muscle mass (-24.8% vs. -10.7%, P < 0.05) and tetanic force (-43.7% vs. -25.9%, P <0.05) during HLS. Although GTE failed to further improve recovery of muscle function or mass compared with vehicle treatment, animals given green tea via gavage maintained the lower losses of muscle mass that were found during HLS (-25.2% vs. -16.0%, P < 0.05) and force (-45.7 vs. -34.4%, P < 0.05) after the reloading periods. In addition, compared with vehicle treatment, GTE attenuated muscle fiber cross-sectional area loss in both plantaris (-39.9% vs. -23.9%, P < 0.05) and soleus (-37.2% vs. -17.6%) muscles after HLS. This green tea-induced difference was not transient but was maintained over the reloading period for plantaris (-45.6% vs. -21.5%, P <0.05) and soleus muscle fiber cross-sectional area (-38.7% vs. -10.9%, P <0.05). GTE increased satellite cell proliferation and differentiation in plantaris and soleus muscles during recovery from HLS compared with vehicle-treated muscles and decreased oxidative stress and abundance of the Bcl-2-associated X protein (Bax), yet this did not further improve muscle recovery in reloaded muscles. These data suggest that muscle recovery following disuse in aging is complex. Although satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is by itself insufficient to

  13. HIF-1-driven skeletal muscle adaptations to chronic hypoxia: molecular insights into muscle physiology.

    PubMed

    Favier, F B; Britto, F A; Freyssenet, D G; Bigard, X A; Benoit, H

    2015-12-01

    Skeletal muscle is a metabolically active tissue and the major body protein reservoir. Drop in ambient oxygen pressure likely results in a decrease in muscle cells oxygenation, reactive oxygen species (ROS) overproduction and stabilization of the oxygen-sensitive hypoxia-inducible factor (HIF)-1α. However, skeletal muscle seems to be quite resistant to hypoxia compared to other organs, probably because it is accustomed to hypoxic episodes during physical exercise. Few studies have observed HIF-1α accumulation in skeletal muscle during ambient hypoxia probably because of its transient stabilization. Nevertheless, skeletal muscle presents adaptations to hypoxia that fit with HIF-1 activation, although the exact contribution of HIF-2, I kappa B kinase and activating transcription factors, all potentially activated by hypoxia, needs to be determined. Metabolic alterations result in the inhibition of fatty acid oxidation, while activation of anaerobic glycolysis is less evident. Hypoxia causes mitochondrial remodeling and enhanced mitophagy that ultimately lead to a decrease in ROS production, and this acclimatization in turn contributes to HIF-1α destabilization. Likewise, hypoxia has structural consequences with muscle fiber atrophy due to mTOR-dependent inhibition of protein synthesis and transient activation of proteolysis. The decrease in muscle fiber area improves oxygen diffusion into muscle cells, while inhibition of protein synthesis, an ATP-consuming process, and reduction in muscle mass decreases energy demand. Amino acids released from muscle cells may also have protective and metabolic effects. Collectively, these results demonstrate that skeletal muscle copes with the energetic challenge imposed by O2 rarefaction via metabolic optimization.

  14. Task constraints and minimization of muscle effort result in a small number of muscle synergies during gait.

    PubMed

    De Groote, Friedl; Jonkers, Ilse; Duysens, Jacques

    2014-01-01

    Finding muscle activity generating a given motion is a redundant problem, since there are many more muscles than degrees of freedom. The control strategies determining muscle recruitment from a redundant set are still poorly understood. One theory of motor control suggests that motion is produced through activating a small number of muscle synergies, i.e., muscle groups that are activated in a fixed ratio by a single input signal. Because of the reduced number of input signals, synergy-based control is low dimensional. But a major criticism on the theory of synergy-based control of muscles is that muscle synergies might reflect task constraints rather than a neural control strategy. Another theory of motor control suggests that muscles are recruited by optimizing performance. Optimization of performance has been widely used to calculate muscle recruitment underlying a given motion while assuming independent recruitment of muscles. If synergies indeed determine muscle recruitment underlying a given motion, optimization approaches that do not model synergy-based control could result in muscle activations that do not show the synergistic muscle action observed through electromyography (EMG). If, however, synergistic muscle action results from performance optimization and task constraints (joint kinematics and external forces), such optimization approaches are expected to result in low-dimensional synergistic muscle activations that are similar to EMG-based synergies. We calculated muscle recruitment underlying experimentally measured gait patterns by optimizing performance assuming independent recruitment of muscles. We found that the muscle activations calculated without any reference to synergies can be accurately explained by on average four synergies. These synergies are similar to EMG-based synergies. We therefore conclude that task constraints and performance optimization explain synergistic muscle recruitment from a redundant set of muscles.

  15. A three-dimensional muscle activity imaging technique for assessing pelvic muscle function

    NASA Astrophysics Data System (ADS)

    Zhang, Yingchun; Wang, Dan; Timm, Gerald W.

    2010-11-01

    A novel multi-channel surface electromyography (EMG)-based three-dimensional muscle activity imaging (MAI) technique has been developed by combining the bioelectrical source reconstruction approach and subject-specific finite element modeling approach. Internal muscle activities are modeled by a current density distribution and estimated from the intra-vaginal surface EMG signals with the aid of a weighted minimum norm estimation algorithm. The MAI technique was employed to minimally invasively reconstruct electrical activity in the pelvic floor muscles and urethral sphincter from multi-channel intra-vaginal surface EMG recordings. A series of computer simulations were conducted to evaluate the performance of the present MAI technique. With appropriate numerical modeling and inverse estimation techniques, we have demonstrated the capability of the MAI technique to accurately reconstruct internal muscle activities from surface EMG recordings. This MAI technique combined with traditional EMG signal analysis techniques is being used to study etiologic factors associated with stress urinary incontinence in women by correlating functional status of muscles characterized from the intra-vaginal surface EMG measurements with the specific pelvic muscle groups that generated these signals. The developed MAI technique described herein holds promise for eliminating the need to place needle electrodes into muscles to obtain accurate EMG recordings in some clinical applications.

  16. Muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction.

    PubMed

    Woźniak, Krzysztof; Lipski, Mariusz; Lichota, Damian; Szyszka-Sommerfeld, Liliana

    2015-01-01

    The aim of this study is to evaluate muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction (TMD). Two hundred volunteers aged 19.3 to 27.8 years (mean 21.50, SD 0.97) participated in this study. Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany). Muscle fatigue was evaluated on the basis of a maximum effort test. The test was performed during a 10-second maximum isometric contraction (MVC) of the jaws. An analysis of changes in the mean power frequency of the two pairs of temporal and masseter muscles (MPF%) revealed significant differences in the groups of patients with varying degrees of temporomandibular disorders according to Di (P < 0.0000). The study showed an increase in the muscle fatigue of the temporal and masseter muscles correlated with the intensity of temporomandibular dysfunction symptoms in patients. The use of surface electromyography in assessing muscle fatigue is an excellent diagnostic tool for identifying patients with temporomandibular dysfunction.

  17. Muscle Fatigue in the Temporal and Masseter Muscles in Patients with Temporomandibular Dysfunction

    PubMed Central

    Woźniak, Krzysztof; Lipski, Mariusz; Lichota, Damian

    2015-01-01

    The aim of this study is to evaluate muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction (TMD). Two hundred volunteers aged 19.3 to 27.8 years (mean 21.50, SD 0.97) participated in this study. Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany). Muscle fatigue was evaluated on the basis of a maximum effort test. The test was performed during a 10-second maximum isometric contraction (MVC) of the jaws. An analysis of changes in the mean power frequency of the two pairs of temporal and masseter muscles (MPF%) revealed significant differences in the groups of patients with varying degrees of temporomandibular disorders according to Di (P < 0.0000). The study showed an increase in the muscle fatigue of the temporal and masseter muscles correlated with the intensity of temporomandibular dysfunction symptoms in patients. The use of surface electromyography in assessing muscle fatigue is an excellent diagnostic tool for identifying patients with temporomandibular dysfunction. PMID:25883949

  18. Reorganization of muscle synergies during multidirectional reaching in the horizontal plane with experimental muscle pain

    PubMed Central

    Muceli, Silvia; Falla, Deborah

    2014-01-01

    Muscle pain induces a complex reorganization of the motor strategy which cannot be fully explained by current theories. We tested the hypothesis that the neural control of muscles during reaching in the presence of nociceptive input is determined by a reorganization of muscle synergies with respect to control conditions. Muscle pain was induced by injection of hypertonic saline into the anterior deltoid muscle of eight men. Electromyographic (EMG) signals were recorded from 12 upper limb muscles as subjects performed a reaching task before (baseline) and after the injection of hypertonic (pain) saline, and after the pain sensation vanished. The EMG envelopes were factorized in muscle synergies, and activation signals extracted for each condition. Nociceptive stimulation resulted in a complex muscle reorganization without changes in the kinematic output. The anterior deltoid muscle activity decreased in all subjects while the changes in other muscles were subject specific. Three synergies sufficed to describe the EMG patterns in each condition, suggesting that reaching movements remain modular in the presence of experimental pain. Muscle reorganization in all subjects was accompanied by a change in the activation signals compatible with a change in the central drive to muscles. One, two or three synergies were shared between the baseline and painful conditions, depending on the subject. These results indicate that nociceptive stimulation may induce a reorganization of modular control in reaching. We speculate that such reorganization may be due to the recruitment of synergies specific to the painful condition. PMID:24453279

  19. The scaling of postcranial muscles in cats (Felidae) I: forelimb, cervical, and thoracic muscles.

    PubMed

    Cuff, Andrew R; Sparkes, Emily L; Randau, Marcela; Pierce, Stephanie E; Kitchener, Andrew C; Goswami, Anjali; Hutchinson, John R

    2016-07-01

    The body masses of cats (Mammalia, Carnivora, Felidae) span a ~300-fold range from the smallest to largest species. Despite this range, felid musculoskeletal anatomy remains remarkably conservative, including the maintenance of a crouched limb posture at unusually large sizes. The forelimbs in felids are important for body support and other aspects of locomotion, as well as climbing and prey capture, with the assistance of the vertebral (and hindlimb) muscles. Here, we examine the scaling of the anterior postcranial musculature across felids to assess scaling patterns between different species spanning the range of felid body sizes. The muscle architecture (lengths and masses of the muscle-tendon unit components) for the forelimb, cervical and thoracic muscles was quantified to analyse how the muscles scale with body mass. Our results demonstrate that physiological cross-sectional areas of the forelimb muscles scale positively with increasing body mass (i.e. becoming relatively larger). Many significantly allometric variables pertain to shoulder support, whereas the rest of the limb muscles become relatively weaker in larger felid species. However, when phylogenetic relationships were corrected for, most of these significant relationships disappeared, leaving no significantly allometric muscle metrics. The majority of cervical and thoracic muscle metrics are not significantly allometric, despite there being many allometric skeletal elements in these regions. When forelimb muscle data were considered in isolation or in combination with those of the vertebral muscles in principal components analyses and MANOVAs, there was no significant discrimination among species by either size or locomotory mode. Our results support the inference that larger felid species have relatively weaker anterior postcranial musculature compared with smaller species, due to an absence of significant positive allometry of forelimb or vertebral muscle architecture. This difference in strength

  20. Muscle activity of leg muscles during unipedal stance on therapy devices with different stability properties.

    PubMed

    Wolburg, Thomas; Rapp, Walter; Rieger, Jochen; Horstmann, Thomas

    2016-01-01

    To test the hypotheses that less stable therapy devices require greater muscle activity and that lower leg muscles will have greater increases in muscle activity with less stable therapy devices than upper leg muscles. Cross-sectional laboratory study. Laboratory setting. Twenty-five healthy subjects. Electromyographic activity of four lower (gastrocnemius medialis, soleus, tibialis anterior, peroneus longus) and four upper leg muscles (vastus medialis and lateralis, biceps femoris, semitendinosus) during unipedal quiet barefoot stance on the dominant leg on a flat rigid surface and on five therapy devices with varying stability properties. Muscle activity during unipedal stance differed significantly between therapy devices (P < 0.001). The order from lowest to highest relative muscle activity matched the order from most to least stable therapy device. There was no significant interaction between muscle location (lower versus upper leg) and therapy device (P = 0.985). Magnitudes of additional relative muscle activity for the respective therapy devices differed substantially among lower extremity muscles. The therapy devices offer a progressive increase in training intensity, and thus may be useful for incremental training programs in physiotherapeutic practice and sports training programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Tbx15 controls skeletal muscle fibre-type determination and muscle metabolism

    PubMed Central

    Lee, Kevin Y.; Singh, Manvendra K.; Ussar, Siegfried; Wetzel, Petra; Hirshman, Michael F.; Goodyear, Laurie J.; Kispert, Andreas; Kahn, C. Ronald

    2015-01-01

    Skeletal muscle is composed of both slow-twitch oxidative myofibers and fast-twitch glycolytic myofibers that differentially impact muscle metabolism, function and eventually whole-body physiology. Here we show that the mesodermal transcription factor T-box 15 (Tbx15) is highly and specifically expressed in glycolytic myofibers. Ablation of Tbx15 in vivo leads to a decrease in muscle size due to a decrease in the number of glycolytic fibres, associated with a small increase in the number of oxidative fibres. This shift in fibre composition results in muscles with slower myofiber contraction and relaxation, and also decreases whole-body oxygen consumption, reduces spontaneous activity, increases adiposity and glucose intolerance. Mechanistically, ablation of Tbx15 leads to activation of AMPK signalling and a decrease in Igf2 expression. Thus, Tbx15 is one of a limited number of transcription factors to be identified with a critical role in regulating glycolytic fibre identity and muscle metabolism. PMID:26299309

  2. Overexpression of IGF-1 attenuates skeletal muscle damage and accelerates muscle regeneration and functional recovery after disuse

    PubMed Central

    Ye, Fan; Mathur, Sunita; Liu, Min; Borst, Stephen E.; Walter, Glenn A.; Sweeney, H. Lee; Vandenborne, Krista

    2014-01-01

    Skeletal muscle is a highly dynamic tissue that responds to endogenous and external stimuli, including alterations in mechanical loading and growth factors. In particular, the antigravity soleus muscle experiences significant muscle atrophy during disuse and extensive muscle damage upon reloading. Since insulin-like growth factor-1 (IGF-1) has been implicated as a central regulator of muscle repair and modulation of muscle size, we examined the effect of viral mediated overexpression of IGF-1 on the soleus muscle following hindlimb cast immobilization and upon reloading. Recombinant IGF-1 cDNA virus was injected into one of the posterior hindlimbs of the mice, while the contralateral limb was injected with saline (control). At 20 weeks of age, both hindlimbs were immobilized for two weeks to induce muscle atrophy in the soleus and ankle plantar flexor muscle group. Subsequently, the mice were allowed to reambulate and muscle damage and recovery was monitored over a period of 2 to 21 days. The primary finding of this study was that IGF-1 overexpression attenuated reloading-induced muscle damage in the soleus muscle, and accelerated muscle regeneration and force recovery. Muscle T2 assessed by MRI, a nonspecific marker of muscle damage, was significantly lower in IGF-1 injected, compared to contralateral soleus muscles at 2 and 5 days reambulation (P<0.05). The reduced prevalence of muscle damage in IGF-1 injected soleus muscles was confirmed on histology, with a lower fraction area of abnormal muscle tissue in IGF-I injected muscles at 2 days reambulation (33.2±3.3%vs 54.1±3.6%, P<0.05). Evidence of the effect of IGF-1 on muscle regeneration included timely increases in the number of central nuclei (21% at 5 days reambulation), paired-box transcription factor 7 (36% at 5 days), embryonic myosin (37% at 10 days), and elevated MyoD mRNA (7-fold at 2 days) in IGF-1 injected limbs (P<0.05). These findings demonstrate a potential role of IGF-1 in protecting unloaded

  3. Fuel-powered artificial muscles.

    PubMed

    Ebron, Von Howard; Yang, Zhiwei; Seyer, Daniel J; Kozlov, Mikhail E; Oh, Jiyoung; Xie, Hui; Razal, Joselito; Hall, Lee J; Ferraris, John P; Macdiarmid, Alan G; Baughman, Ray H

    2006-03-17

    Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher.

  4. Objective Evaluation of Muscle Strength in Infants with Hypotonia and Muscle Weakness

    ERIC Educational Resources Information Center

    Reus, Linda; van Vlimmeren, Leo A.; Staal, J. Bart; Janssen, Anjo J. W. M.; Otten, Barto J.; Pelzer, Ben J.; Nijhuis-van der Sanden, Maria W. G.

    2013-01-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17…

  5. Experimental comparisons between McKibben type artificial muscles and straight fibers type artificial muscles

    NASA Astrophysics Data System (ADS)

    Nakamura, Taro

    2007-01-01

    This paper describes experimental comparison between a conventional McKibben type artificial muscle and a straight fibers type artificial muscle developed by the authors. A wearable device and a rehabilitation robot which assists a human muscle should have characteristics similar to those of human muscle. In addition, because the wearable device and the rehabilitation robot should be light, an actuator with a high power/weight ratio is needed. At present, the McKibben type is widely used as an artificial muscle, but in fact its physical model is highly nonlinear. Further, the heat and mechanical loss of this actuator are large because of the friction caused by the expansion and contraction of the sleeve. Therefore, the authors have developed an artificial muscle tube in which high strength glass fibers have been built into the tube made from natural latex rubber. As results, experimental results demonstrated that the developed artificial muscle is more effective regarding its fundamental characteristics than that of the McKibben type; the straight fibers types of artificial muscle have more contraction ratio and power, longer lifetime than the McKibben types. And it has almost same characteristics of human muscle for isotonic and isometric that evaluate it dynamically.

  6. Characterization of muscle ankyrin repeat proteins in human skeletal muscle.

    PubMed

    Wette, Stefan G; Smith, Heather K; Lamb, Graham D; Murphy, Robyn M

    2017-09-01

    Muscle ankyrin repeat proteins (MARPs) are a family of titin-associated, stress-response molecules and putative transducers of stretch-induced signaling in skeletal muscle. In cardiac muscle, cardiac ankyrin repeat protein (CARP) and diabetes-related ankyrin repeat protein (DARP) reportedly redistribute from binding sites on titin to the nucleus following a prolonged stretch. However, it is unclear whether ankyrin repeat domain protein 2 (Ankrd 2) shows comparable stretch-induced redistribution to the nucleus. We measured the following in rested human skeletal muscle: 1 ) the absolute amount of MARPs and 2 ) the distribution of Ankrd 2 and DARP in both single fibers and whole muscle preparations. In absolute amounts, Ankrd 2 is the most abundant MARP in human skeletal muscle, there being ~3.1 µmol/kg, much greater than DARP and CARP (~0.11 and ~0.02 µmol/kg, respectively). All DARP was found to be tightly bound at cytoskeletal (or possibly nuclear) sites. In contrast, ~70% of the total Ankrd 2 is freely diffusible in the cytosol [including virtually all of the phosphorylated (p)Ankrd 2-Ser99 form], ~15% is bound to non-nuclear membranes, and ~15% is bound at cytoskeletal sites, likely at the N2A region of titin. These data are not consistent with the proposal that Ankrd 2, per se, or pAnkrd 2-Ser99 mediates stretch-induced signaling in skeletal muscle, dissociating from titin and translocating to the nucleus, because the majority of these forms of Ankrd 2 are already free in the cytosol. It will be necessary to show that the titin-associated Ankrd 2 is modified by stretch in some as-yet-unidentified way, distinct from the diffusible pool, if it is to act as a stretch-sensitive signaling molecule. Copyright © 2017 the American Physiological Society.

  7. Lean muscle volume of the thigh has a stronger relationship with muscle power than muscle strength in women with knee osteoarthritis.

    PubMed

    Davison, Michael J; Maly, Monica R; Keir, Peter J; Hapuhennedige, Sandani M; Kron, Amie T; Adachi, Jonathan D; Beattie, Karen A

    2017-01-01

    Thigh lean muscle and intramuscular fat have been implicated in the impairment of physical function observed in people with knee osteoarthritis. We investigated the relationships of quadriceps and hamstrings intramuscular fat fraction and lean muscle volume with muscle power and strength, controlling for neuromuscular activation, and physical performance in women with knee OA. Women (n=20) 55years or older with symptomatic, radiographic knee osteoarthritis underwent a 3.0T magnetic resonance imaging scan of the thigh of their most symptomatic knee. Axial fat-separated images were analyzed using software to quantify intramuscular fat and lean muscle volumes of the quadriceps and hamstrings. To quantify strength and power of the knee extensors and flexors, participants performed maximum voluntary isometric contraction and isotonic knee extensions and flexions, respectively. Electromyography of the quadriceps and hamstrings was measured. Participants also completed five physical performance tests. Quadriceps and hamstrings lean muscle volumes were related to isotonic knee extensor (B=0.624; p=0.017) and flexor (B=1.518; p=0.032) power, but not knee extensor (B=0.001; p=0.615) or flexor (B=0.001; p=0.564) isometric strength. Intramuscular fat fractions were not related to isotonic knee extensor or flexor power, nor isometric strength. No relationships were found between intramuscular fat or lean muscle volume and physical performance. Muscle power may be more sensitive than strength to lean muscle mass in women with knee osteoarthritis. Thigh lean muscle mass, but neither intramuscular nor intermuscular fat, is related to knee extensor and flexor power in women with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Persistence of Vibrio vulnificus in tissues of Gulf Coast oysters, Crassostrea virginica, exposed to seawater disinfected with UV light.

    PubMed

    Tamplin, M L; Capers, G M

    1992-05-01

    Vibrio vulnificus is an estuarine bacterium which can cause opportunistic infections in humans consuming raw Gulf Coast oysters, Crassostrea virginica. Although V. vulnificus is known as a ubiquitous organism in the Gulf of Mexico, its ecological relationship with C. virginica has not been adequately defined. The objective of the present study was to test the hypothesis that V. vulnificus is a persistent microbial flora of oysters and unamenable to traditional methods of controlled purification, such as UV light depuration. Experimental depuration systems consisted of aquaria containing temperature-controlled seawater treated with UV light and 0.2-microns-pore-size filtration. V. vulnificus was enumerated in seawater, oyster shell biofilms, homogenates of whole oyster meats, and tissues including the hemolymph, digestive region, gills, mantle, and adductor muscle. Results showed that depuration systems conducted at temperatures greater than 23 degrees C caused V. vulnificus counts to increase in oysters, especially in the hemolymph, adductor muscle, and mantle. Throughout the process, depuration water contained high concentrations of V. vulnificus, indicating that the disinfection properties of UV radiation and 0.2-microns-pore-size filtration were less than the rate at which V. vulnificus was released into seawater. Approximately 10(5) to 10(6) V. vulnificus organisms were released from each oyster per hour, with 0.05 to 35% originating from shell surfaces. These surfaces contained greater than 10(3) V. vulnificus organisms per cm2. In contrast, when depuration seawater was maintained at 15 degrees C, V. vulnificus was not detected in seawater and multiplication in oyster tissues was inhibited.

  9. Action of Obestatin in Skeletal Muscle Repair: Stem Cell Expansion, Muscle Growth, and Microenvironment Remodeling

    PubMed Central

    Gurriarán-Rodríguez, Uxía; Santos-Zas, Icía; González-Sánchez, Jessica; Beiroa, Daniel; Moresi, Viviana; Mosteiro, Carlos S; Lin, Wei; Viñuela, Juan E; Señarís, José; García-Caballero, Tomás; Casanueva, Felipe F; Nogueiras, Rubén; Gallego, Rosalía; Renaud, Jean-Marc; Adamo, Sergio; Pazos, Yolanda; Camiña, Jesús P

    2015-01-01

    The development of therapeutic strategies for skeletal muscle diseases, such as physical injuries and myopathies, depends on the knowledge of regulatory signals that control the myogenic process. The obestatin/GPR39 system operates as an autocrine signal in the regulation of skeletal myogenesis. Using a mouse model of skeletal muscle regeneration after injury and several cellular strategies, we explored the potential use of obestatin as a therapeutic agent for the treatment of trauma-induced muscle injuries. Our results evidenced that the overexpression of the preproghrelin, and thus obestatin, and GPR39 in skeletal muscle increased regeneration after muscle injury. More importantly, the intramuscular injection of obestatin significantly enhanced muscle regeneration by simulating satellite stem cell expansion as well as myofiber hypertrophy through a kinase hierarchy. Added to the myogenic action, the obestatin administration resulted in an increased expression of vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor 2 (VEGFR2) and the consequent microvascularization, with no effect on collagen deposition in skeletal muscle. Furthermore, the potential inhibition of myostatin during obestatin treatment might contribute to its myogenic action improving muscle growth and regeneration. Overall, our data demonstrate successful improvement of muscle regeneration, indicating obestatin is a potential therapeutic agent for skeletal muscle injury and would benefit other myopathies related to muscle regeneration. PMID:25762009

  10. Muscle regeneration during hindlimb unloading results in a reduction in muscle size after reloading

    NASA Technical Reports Server (NTRS)

    Mozdziak, P. E.; Pulvermacher, P. M.; Schultz, E.

    2001-01-01

    The hindlimb-unloading model was used to study the ability of muscle injured in a weightless environment to recover after reloading. Satellite cell mitotic activity and DNA unit size were determined in injured and intact soleus muscles from hindlimb-unloaded and age-matched weight-bearing rats at the conclusion of 28 days of hindlimb unloading, 2 wk after reloading, and 9 wk after reloading. The body weights of hindlimb-unloaded rats were significantly (P < 0.05) less than those of weight-bearing rats at the conclusion of hindlimb unloading, but they were the same (P > 0.05) as those of weight-bearing rats 2 and 9 wk after reloading. The soleus muscle weight, soleus muscle weight-to-body weight ratio, myofiber diameter, number of nuclei per millimeter, and DNA unit size were significantly (P < 0.05) smaller for the injured soleus muscles from hindlimb-unloaded rats than for the soleus muscles from weight-bearing rats at each recovery time. Satellite cell mitotic activity was significantly (P < 0.05) higher in the injured soleus muscles from hindlimb-unloaded rats than from weight-bearing rats 2 wk after reloading, but it was the same (P > 0.05) as in the injured soleus muscles from weight-bearing rats 9 wk after reloading. The injured soleus muscles from hindlimb-unloaded rats failed to achieve weight-bearing muscle size 9 wk after reloading, because incomplete compensation for the decrease in myonuclear accretion and DNA unit size expansion occurred during the unloading period.

  11. Macrophage depletion impairs skeletal muscle regeneration: The roles of regulatory factors for muscle regeneration.

    PubMed

    Liu, Xiaoguang; Liu, Yu; Zhao, Linlin; Zeng, Zhigang; Xiao, Weihua; Chen, Peijie

    2017-03-01

    Though macrophages are essential for skeletal muscle regeneration, which is a complex process, the roles and mechanisms of the macrophages in the process of muscle regeneration are still not fully understood. The objective of this study is to explore the roles of macrophages and the mechanisms involved in the regeneration of injured skeletal muscle. One hundred and twelve C57BL/6 mice were randomly divided into muscle contusion and macrophages depleted groups. Their gastrocnemius muscles were harvested at the time points of 12 h, 1, 3, 5, 7, 14 d post-injury. The changes in skeletal muscle morphology were assessed by hematoxylin and eosin (HE) stain. The gene expression was analyzed by real-time polymerase chain reaction. The data showed that CL-liposomes treatment did affect the expression of myogenic regulatory factors (MyoD, myogenin) after injury. In addition, CL-liposomes treatment decreased the expression of regulatory factors of muscle regeneration (HGF, uPA, COX-2, IGF-1, MGF, FGF6) and increased the expression of inflammatory cytokines (TGF-β1, TNF-α, IL-1β, RANTES) in the late stage of regeneration. Moreover, there were significant correlations between macrophages and some regulatory factors (such as HGF, uPA) for muscle regeneration. These results suggested that macrophages depletion impairs skeletal muscle regeneration and that the regulatory factors for muscle regeneration may play important roles in this process. © 2017 International Federation for Cell Biology.

  12. Exercise-induced muscle glucose uptake in mice with graded, muscle-specific GLUT-4 deletion

    PubMed Central

    Howlett, Kirsten F; Andrikopoulos, Sofianos; Proietto, Joseph; Hargreaves, Mark

    2013-01-01

    To investigate the importance of the glucose transporter GLUT-4 for muscle glucose uptake during exercise, transgenic mice with skeletal muscle GLUT-4 expression approximately 30–60% of normal (CON) and approximately 5–10% of normal (KO) were generated using the Cre/Lox system and compared with wild-type (WT) mice during approximately 40 min of treadmill running (KO: 37.7 ± 1.3 min; WT: 40 min; CON: 40 min, P = 0.18). In WT and CON animals, exercise resulted in an overall increase in muscle glucose uptake. More specifically, glucose uptake was increased in red gastrocnemius of WT mice and in the soleus and red gastrocnemius of CON mice. In contrast, the exercise-induced increase in muscle glucose uptake in all muscles was completely abolished in KO mice. Muscle glucose uptake increased during exercise in both red and white quadriceps of WT mice, while the small increases in CON mice were not statistically significant. In KO mice, there was no change at all in quadriceps muscle glucose uptake. No differences in muscle glycogen use during exercise were observed between any of the groups. However, there was a significant increase in plasma glucose levels after exercise in KO mice. The results of this study demonstrated that a reduction in skeletal muscle GLUT-4 expression to approximately 10% of normal levels completely abolished the exercise-induced increase in muscle glucose uptake. PMID:24303141

  13. Biceps brachii muscle oxygenation in electrical muscle stimulation.

    PubMed

    Muthalib, Makii; Jubeau, Marc; Millet, Guillaume Y; Maffiuletti, Nicola A; Ferrari, Marco; Nosaka, Kazunori

    2010-09-01

    The purpose of this study was to compare between electrical muscle stimulation (EMS) and maximal voluntary (VOL) isometric contractions of the elbow flexors for changes in biceps brachii muscle oxygenation (tissue oxygenation index, TOI) and haemodynamics (total haemoglobin volume, tHb = oxygenated-Hb + deoxygenated-Hb) determined by near-infrared spectroscopy (NIRS). The biceps brachii muscle of 10 healthy men (23-39 years) was electrically stimulated at high frequency (75 Hz) via surface electrodes to evoke 50 intermittent (4-s contraction, 15-s relaxation) isometric contractions at maximum tolerated current level (EMS session). The contralateral arm performed 50 intermittent (4-s contraction, 15-s relaxation) maximal voluntary isometric contractions (VOL session) in a counterbalanced order separated by 2-3 weeks. Results indicated that although the torque produced during EMS was approximately 50% of VOL (P<0.05), there was no significant difference in the changes in TOI amplitude or TOI slope between EMS and VOL over the 50 contractions. However, the TOI amplitude divided by peak torque was approximately 50% lower for EMS than VOL (P<0.05), which indicates EMS was less efficient than VOL. This seems likely because of the difference in the muscles involved in the force production between conditions. Mean decrease in tHb amplitude during the contraction phases was significantly (P<0.05) greater for EMS than VOL from the 10th contraction onwards, suggesting that the muscle blood volume was lower in EMS than VOL. It is concluded that local oxygen demand of the biceps brachii sampled by NIRS is similar between VOL and EMS.

  14. Platelet-Derived Growth Factor BB Influences Muscle Regeneration in Duchenne Muscle Dystrophy.

    PubMed

    Piñol-Jurado, Patricia; Gallardo, Eduard; de Luna, Noemi; Suárez-Calvet, Xavier; Sánchez-Riera, Carles; Fernández-Simón, Esther; Gomis, Clara; Illa, Isabel; Díaz-Manera, Jordi

    2017-08-01

    Duchenne muscular dystrophy (DMD) is characterized by a progressive loss of muscle fibers, and their substitution by fibrotic and adipose tissue. Many factors contribute to this process, but the molecular pathways related to regeneration and degeneration of muscle are not completely known. Platelet-derived growth factor (PDGF)-BB belongs to a family of growth factors that regulate proliferation, migration, and differentiation of mesenchymal cells. The role of PDGF-BB in muscle regeneration in humans has not been studied. We analyzed the expression of PDGF-BB in muscle biopsy samples from controls and patients with DMD. We performed in vitro experiments to understand the effects of PDGF-BB on myoblasts involved in the pathophysiology of muscular dystrophies and confirmed our results in vivo by treating the mdx murine model of DMD with repeated i.m. injections of PDGF-BB. We observed that regenerating and necrotic muscle fibers in muscle biopsy samples from DMD patients expressed PDGF-BB. In vitro, PDGF-BB attracted myoblasts and activated their proliferation. Analysis of muscles from the animals treated with PDGF-BB showed an increased population of satellite cells and an increase in the number of regenerative fibers, with a reduction in inflammatory infiltrates, compared with those in vehicle-treated mice. Based on our results, PDGF-BB may play a protective role in muscular dystrophies by enhancing muscle regeneration through activation of satellite cell proliferation and migration. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  15. Autologous Minced Muscle Grafts: A Tissue Engineering Therapy for the Volumetric Loss of Skeletal Muscle

    DTIC Science & Technology

    2013-07-24

    report that over the first 16 wk postinjury, MG transplantation 1) promotes remarkable regeneration of innervated muscle fibers within the defect area...i.e., de novo muscle fiber regeneration); 2) reduced evidence of chronic injury in the remaining muscle mass compared with nonrepaired muscles ...cated nuclei in 30% of fibers observed in nonrepaired muscles ); and 3) significantly improves net torque production (i.e., 55% of the functional deficit

  16. Muscle Damage and Its Relationship with Muscle Fatigue During a Half-Iron Triathlon

    PubMed Central

    Coso, Juan Del; González-Millán, Cristina; Salinero, Juan José; Abián-Vicén, Javier; Soriano, Lidón; Garde, Sergio; Pérez-González, Benito

    2012-01-01

    Background To investigate the cause/s of muscle fatigue experienced during a half-iron distance triathlon. Methodology/Principal Findings We recruited 25 trained triathletes (36±7 yr; 75.1±9.8 kg) for the study. Before and just after the race, jump height and leg muscle power output were measured during a countermovement jump on a force platform to determine leg muscle fatigue. Body weight, handgrip maximal force and blood and urine samples were also obtained before and after the race. Blood myoglobin and creatine kinase concentrations were determined as markers of muscle damage. Results Jump height (from 30.3±5.0 to 23.4±6.4 cm; P<0.05) and leg power output (from 25.6±2.9 to 20.7±4.6 W · kg−1; P<0.05) were significantly reduced after the race. However, handgrip maximal force was unaffected by the race (430±59 to 430±62 N). Mean dehydration after the race was 2.3±1.2% with high inter-individual variability in the responses. Blood myoglobin and creatine kinase concentration increased to 516±248 µg · L−1 and 442±204 U · L−1, respectively (P<0.05) after the race. Pre- to post-race jump change did not correlate with dehydration (r = 0.16; P>0.05) but significantly correlated with myoglobin concentration (r = 0.65; P<0.001) and creatine kinase concentration (r = 0.54; P<0.001). Conclusions/significance During a half-iron distance triathlon, the capacity of leg muscles to produce force was notably diminished while arm muscle force output remained unaffected. Leg muscle fatigue was correlated with blood markers of muscle damage suggesting that muscle breakdown is one of the most relevant sources of muscle fatigue during a triathlon. PMID:22900101

  17. The Drosophila indirect flight muscle myosin heavy chain isoform is insufficient to transform the jump muscle into a highly stretch-activated muscle type

    PubMed Central

    Zhao, Cuiping

    2017-01-01

    Stretch activation (SA) is a delayed increase in force that enables high power and efficiency from a cyclically contracting muscle. SA exists in various degrees in almost all muscle types. In Drosophila, the indirect flight muscle (IFM) displays exceptionally high SA force production (FSA), whereas the jump muscle produces only minimal FSA. We previously found that expressing an embryonic (EMB) myosin heavy chain (MHC) isoform in the jump muscle transforms it into a moderately SA muscle type and enables positive cyclical power generation. To investigate whether variation in MHC isoforms is sufficient to produce even higher FSA, we substituted the IFM MHC isoform (IFI) into the jump muscle. Surprisingly, we found that IFI only caused a 1.7-fold increase in FSA, less than half the increase previously observed with EMB, and only at a high Pi concentration, 16 mM. This IFI-induced FSA is much less than what occurs in IFM, relative to isometric tension, and did not enable positive cyclical power generation by the jump muscle. Both isometric tension and FSA of control fibers decreased with increasing Pi concentration. However, for IFI-expressing fibers, only isometric tension decreased. The rate of FSA generation was ~1.5-fold faster for IFI fibers than control fibers, and both rates were Pi dependent. We conclude that MHC isoforms can alter FSA and hence cyclical power generation but that isoforms can only endow a muscle type with moderate FSA. Highly SA muscle types, such as IFM, likely use a different or additional mechanism. PMID:27881413

  18. Plakins in striated muscle.

    PubMed

    Boyer, Justin G; Bernstein, Marija A; Boudreau-Larivière, Céline

    2010-03-01

    Striated muscle cells contain numerous architectural proteins that contribute to the function of muscle as generators of mechanical force. Among these proteins are crosslinkers belonging to the plakin family, namely plectin, microtubule-actin crosslinking factor (ACF7/MACF1), bullous pemphigoid antigen 1 (Bpag1/dystonin), and desmoplakin. These plakin family members, in particular plectin and Bpag1/dystonin, exist as several isoforms. The domain organization of these plakin variants dictates their subcellular location and the proteins with which they interact. Several studies suggest that plakins exert unique functions within various compartments of the muscle cell including the sarcolemma, the sarcomere, both neuromuscular and myotendinous junctions in skeletal muscle, and the intercalated discs in cardiac muscle. Plakins may also regulate the cellular placement and function of specific organelles, notably the nucleus, mitochondria, Golgi apparatus, and sarcoplasmic reticulum. Here we review and summarize our current knowledge of the function of plakins in striated muscle cells.

  19. Muscle development and obesity

    PubMed Central

    2008-01-01

    The formation of skeletal muscle from the epithelial somites involves a series of events triggered by temporally and spatially discrete signals resulting in the generation of muscle fibers which vary in their contractile and metabolic nature. The fiber type composition of muscles varies between individuals and it has now been found that there are differences in fiber type proportions between lean and obese animals and humans. Amongst the possible causes of obesity, it has been suggested that inappropriate prenatal environments may ‘program’ the fetus and may lead to increased risks for disease in adult life. The characteristics of muscle are both heritable and plastic, giving the tissue some ability to adapt to signals and stimuli both pre and postnatally. Given that muscle is a site of fatty acid oxidation and carbohydrate metabolism and that its development can be changed by prenatal events, it is interesting to examine the possible relationship between muscle development and the risk of obesity. PMID:19279728

  20. Morphology of the lumbar transversospinal muscles examined in a mouse bearing a muscle fiber-specific nuclear marker.

    PubMed

    Cornwall, Jon; Deries, Marianne; Duxson, Marilyn

    2010-12-01

    Although the morphology of human lumbar transversospinal (TSP) muscles has been studied, little is known about the structure of these muscles in the mouse (Mus musculus). Such information is relevant given mice are often used as a "normal" phenotype for studies modeling human development. This study describes the gross morphology, muscle fiber arrangement, and innervation pattern of the mouse lumbar TSP muscles. A unique feature of the study is the use of a transgenic mouse line bearing a muscle-specific nuclear marker that allows clear delineation of muscle fiber and connective tissue boundaries. The lumbar TSP muscles of five mice were examined bilaterally; at each spinal level muscles attached to the caudal edge of the spinous process and passed caudally as a single complex unit. Fibers progressively terminated over the four vertebral segments caudad, with multiple points of muscle fiber attachment on each vertebra. Motor endplates, defined with acetylcholinesterase histochemistry, were consistently located half way along each muscle fiber, regardless of length, with all muscle fibers arranged in-parallel rather than in-series. These results provide information relevant to interpretation of developmental and functional studies involving this muscle group in the mouse and show mouse lumbar TSP muscles are different in form to descriptions of equivalent muscles in humans and horses.

  1. Triceps brachii muscle reconstruction with a latissimus dorsi muscle flap in a dog.

    PubMed

    Pavletic, Michael M; Kalis, Russell; Tribou, Patricia; Mouser, Pam J

    2015-01-15

    A 6-year-old spayed female Border Collie was examined for a severe deformity of the right forelimb. Three months prior to examination, the patient awkwardly fell off the couch and became acutely lame in the right forelimb, progressing to non-weight bearing over the following 72 hours. On physical examination, the dog carried the limb caudally against the thoracic wall, with the shoulder flexed and elbow in extension. The right triceps brachii muscle was atrophied and contracted, resulting in a resistant tension band effect that precluded manipulation of the right elbow joint. The physical changes in the triceps muscle were considered the primary cause of the patient's loss of limb function. Surgical treatment by means of elevation and transposition of the ipsilateral latissimus dorsi muscle was performed. The exposed triceps brachii muscles were transected 3 cm proximal to the tendons of insertion. Via a separate incision, the right latissimus dorsi muscle was elevated and tunneled subcutaneously beneath the interposing skin between the 2 surgical incisions. The muscle was then positioned and sutured to the proximal and distal borders of the divided triceps muscle group. Two weeks later, physical therapy was initiated. After 2 months, the patient regularly walked on the limb most of the time (9/10 steps). The surgical procedure for elevation and transposition of the latissimus dorsi muscle was relatively simple to perform. Physical therapy was an essential component to achieving the successful functional outcome in this case. This technique may be considered for treatment of similar patients in which the triceps muscle group is severely compromised.

  2. New twist on artificial muscles.

    PubMed

    Haines, Carter S; Li, Na; Spinks, Geoffrey M; Aliev, Ali E; Di, Jiangtao; Baughman, Ray H

    2016-10-18

    Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy.

  3. New twist on artificial muscles

    PubMed Central

    Haines, Carter S.; Li, Na; Spinks, Geoffrey M.; Aliev, Ali E.; Di, Jiangtao; Baughman, Ray H.

    2016-01-01

    Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy. PMID:27671626

  4. Comparison of isokinetic muscle strength and muscle power by types of warm-up.

    PubMed

    Sim, Young-Je; Byun, Yong-Hyun; Yoo, Jaehyun

    2015-05-01

    [Purpose] The purpose of this study was to clarify the influence of static stretching at warm-up on the isokinetic muscle torque (at 60°/sec) and muscle power (at 180°/sec) of the flexor muscle and extensor muscle of the knee joint. [Subjects and Methods] The subjects of this study were 10 healthy students with no medically specific findings. The warm-up group and warm-up with stretching group performed their respective warm-up prior to the isokinetic muscle torque evaluation of the knee joint. One-way ANOVA was performed by randomized block design for each variable. [Results] The results were as follows: First, the flexor peak torque and extensor peak torque of the knee joint tended to decrease at 60°/sec in the warm-up with stretching group compared with the control group and warm-up group, but without statistical significance. Second, extensor power at 180°/sec was also not statistically significant. However, it was found that flexor power increased significantly in the warm-up with stretching group at 180°/sec compared with the control group and warm-up group in which stretching was not performed. [Conclusion] Therefore, it is considered that in healthy adults, warm-up including two sets of stretching for 20 seconds per muscle group does not decrease muscle strength and muscle power.

  5. Hypoxia inducible factor 1 links fast-patterned muscle activity and fast muscle phenotype in rats.

    PubMed

    Lunde, Ida G; Anton, Siobhan L; Bruusgaard, Jo C; Rana, Zaheer A; Ellefsen, Stian; Gundersen, Kristian

    2011-03-15

    Exercise influences muscle phenotype by the specific pattern of action potentials delivered to the muscle, triggering intracellular signalling pathways. PO2 can be reduced by an order of magnitude in working muscle. In humans, carriers of a hyperactive polymorphism of the transcription factor hypoxia inducible factor 1α (HIF-1α) have 50% more fast fibres, and this polymorphism is prevalent among strength athletes. We have investigated the putative role of HIF-1α in mediating activity changes in muscle.When rat muscles were stimulated with short high frequency bursts of action potentials known to induce a fast muscle phenotype, HIF-1α increased by about 80%. In contrast, a pattern consisting of long low frequency trains known to make fast muscles slow reduced the HIF-1α level of the fast extensor digitorum longus (EDL) muscle by 44%. Nuclear protein extracts from normal EDL contained 2.3-fold more HIF-1α and 4-fold more HIF-1β than the slow soleus muscle, while von-Hippel-Lindau protein was 4.8-fold higher in slow muscles. mRNA displayed a reciprocal pattern; thus FIH-1 mRNA was almost 2-fold higher in fast muscle, while the HIF-1α level was half, and consequently protein/mRNA ratio for HIF-1α was more than 4-fold higher in the fast muscle, suggesting that HIF-1α is strongly suppressed post-transcriptionally in slow muscles.When HIF-1α was overexpressed for 14 days after somatic gene transfer in adult rats, a slow-to-fast transformation was observed, encompassing an increase in fibre cross sectional area, oxidative enzyme activity and myosin heavy chain. The latter was shown to be regulated at the mRNA level in C2C12 myotubes.

  6. Research opportunities in muscle atrophy

    NASA Technical Reports Server (NTRS)

    Herbison, G. J. (Editor); Talbot, J. M. (Editor)

    1984-01-01

    Muscle atrophy in a weightless environment is studied. Topics of investigation include physiological factors of muscle atrophy in space flight, biochemistry, countermeasures, modelling of atrophied muscle tissue, and various methods of measurement of muscle strength and endurance. A review of the current literature and suggestions for future research are included.

  7. Baroreflex modulation of muscle sympathetic nerve activity during posthandgrip muscle ischemia in humans

    NASA Technical Reports Server (NTRS)

    Cui, J.; Wilson, T. E.; Shibasaki, M.; Hodges, N. A.; Crandall, C. G.

    2001-01-01

    To identify whether muscle metaboreceptor stimulation alters baroreflex control of muscle sympathetic nerve activity (MSNA), MSNA, beat-by-beat arterial blood pressure (Finapres), and electrocardiogram were recorded in 11 healthy subjects in the supine position. Subjects performed 2 min of isometric handgrip exercise at 40% of maximal voluntary contraction followed by 2.5 min of posthandgrip muscle ischemia. During muscle ischemia, blood pressure was lowered and then raised by intravenous bolus infusions of sodium nitroprusside and phenylephrine HCl, respectively. The slope of the relationship between MSNA and diastolic blood pressure was more negative (P < 0.001) during posthandgrip muscle ischemia (-201.9 +/- 20.4 units. beat(-1). mmHg(-1)) when compared with control conditions (-142.7 +/- 17.3 units. beat(-1). mmHg(-1)). No significant change in the slope of the relationship between heart rate and systolic blood pressure was observed. However, both curves shifted during postexercise ischemia to accommodate the elevation in blood pressure and MSNA that occurs with this condition. These data suggest that the sensitivity of baroreflex modulation of MSNA is elevated by muscle metaboreceptor stimulation, whereas the sensitivity of baroreflex of modulate heart rate is unchanged during posthandgrip muscle ischemia.

  8. Importance of contraction history on muscle force of porcine urinary bladder smooth muscle.

    PubMed

    Menzel, Robin; Böl, Markus; Siebert, Tobias

    2017-02-01

    The purpose of this study was to provide a comprehensive dataset of porcine urinary bladder smooth muscle properties. Particularly, the history dependence of force production, namely force depression (FD) following shortening and force enhancement (FE) following stretch, was analysed. During active micturition, the circumference of the urinary bladder changes enormously. Thus, FD might be an important phenomenon during smooth muscle contraction. Electrically stimulated, intact urinary bladder strips from pigs (n = 10) were suspended in an aerated-filled organ bath, and different isometric, isotonic, and isokinetic contraction protocols were performed to determine the force-length and the force-velocity relation. FD and FE were assessed in concentric and eccentric contractions with different ramp lengths and ramp velocities. Bladder smooth muscles exhibit considerable amounts of FD and FE. The amount of FD increased significantly with ramp length, while FE did not change. However, FE and FD were independent of ramp velocity. The results imply that smooth muscle bladder strips exhibit similar muscle properties and history-dependent behaviour compared to striated muscles. The provided dataset of muscle properties is important for bladder modelling as well as for the analyses and interpretation of dynamic bladder filling and voiding.

  9. Atrogin-1, a muscle-specific F-box protein highly expressed during muscle atrophy

    NASA Technical Reports Server (NTRS)

    Gomes, M. D.; Lecker, S. H.; Jagoe, R. T.; Navon, A.; Goldberg, A. L.

    2001-01-01

    Muscle wasting is a debilitating consequence of fasting, inactivity, cancer, and other systemic diseases that results primarily from accelerated protein degradation by the ubiquitin-proteasome pathway. To identify key factors in this process, we have used cDNA microarrays to compare normal and atrophying muscles and found a unique gene fragment that is induced more than ninefold in muscles of fasted mice. We cloned this gene, which is expressed specifically in striated muscles. Because this mRNA also markedly increases in muscles atrophying because of diabetes, cancer, and renal failure, we named it atrogin-1. It contains a functional F-box domain that binds to Skp1 and thereby to Roc1 and Cul1, the other components of SCF-type Ub-protein ligases (E3s), as well as a nuclear localization sequence and PDZ-binding domain. On fasting, atrogin-1 mRNA levels increase specifically in skeletal muscle and before atrophy occurs. Atrogin-1 is one of the few examples of an F-box protein or Ub-protein ligase (E3) expressed in a tissue-specific manner and appears to be a critical component in the enhanced proteolysis leading to muscle atrophy in diverse diseases.

  10. 3D Cell Printing of Functional Skeletal Muscle Constructs Using Skeletal Muscle-Derived Bioink.

    PubMed

    Choi, Yeong-Jin; Kim, Taek Gyoung; Jeong, Jonghyeon; Yi, Hee-Gyeong; Park, Ji Won; Hwang, Woonbong; Cho, Dong-Woo

    2016-10-01

    Engineered skeletal muscle tissues that mimic the structure and function of native muscle have been considered as an alternative strategy for the treatment of various muscular diseases and injuries. Here, it is demonstrated that 3D cell-printing of decellularized skeletal muscle extracellular matrix (mdECM)-based bioink facilitates the fabrication of functional skeletal muscle constructs. The cellular alignment and the shape of the tissue constructs are controlled by 3D cell-printing technology. mdECM bioink provides the 3D cell-printed muscle constructs with a myogenic environment that supports high viability and contractility as well as myotube formation, differentiation, and maturation. More interestingly, the preservation of agrin is confirmed in the mdECM, and significant increases in the formation of acetylcholine receptor clusters are exhibited in the 3D cell-printed muscle constructs. In conclusion, mdECM bioink and 3D cell-printing technology facilitate the mimicking of both the structural and functional properties of native muscle and hold great promise for producing clinically relevant engineered muscle for the treatment of muscular injuries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Direct optical activation of skeletal muscle fibres efficiently controls muscle contraction and attenuates denervation atrophy

    PubMed Central

    Magown, Philippe; Shettar, Basavaraj; Zhang, Ying; Rafuse, Victor F.

    2015-01-01

    Neural prostheses can restore meaningful function to paralysed muscles by electrically stimulating innervating motor axons, but fail when muscles are completely denervated, as seen in amyotrophic lateral sclerosis, or after a peripheral nerve or spinal cord injury. Here we show that channelrhodopsin-2 is expressed within the sarcolemma and T-tubules of skeletal muscle fibres in transgenic mice. This expression pattern allows for optical control of muscle contraction with comparable forces to nerve stimulation. Force can be controlled by varying light pulse intensity, duration or frequency. Light-stimulated muscle fibres depolarize proportionally to light intensity and duration. Denervated triceps surae muscles transcutaneously stimulated optically on a daily basis for 10 days show a significant attenuation in atrophy resulting in significantly greater contractile forces compared with chronically denervated muscles. Together, this study shows that channelrhodopsin-2/H134R can be used to restore function to permanently denervated muscles and reduce pathophysiological changes associated with denervation pathologies. PMID:26460719

  12. Daily muscle stretching enhances blood flow, endothelial function, capillarity, vascular volume and connectivity in aged skeletal muscle.

    PubMed

    Hotta, Kazuki; Behnke, Bradley J; Arjmandi, Bahram; Ghosh, Payal; Chen, Bei; Brooks, Rachael; Maraj, Joshua J; Elam, Marcus L; Maher, Patrick; Kurien, Daniel; Churchill, Alexandra; Sepulveda, Jaime L; Kabolowsky, Max B; Christou, Demetra D; Muller-Delp, Judy M

    2018-05-15

    In aged rats, daily muscle stretching increases blood flow to skeletal muscle during exercise. Daily muscle stretching enhanced endothelium-dependent vasodilatation of skeletal muscle resistance arterioles of aged rats. Angiogenic markers and capillarity increased in response to daily stretching in muscles of aged rats. Muscle stretching performed with a splint could provide a feasible means of improving muscle blood flow and function in elderly patients who cannot perform regular aerobic exercise. Mechanical stretch stimuli alter the morphology and function of cultured endothelial cells; however, little is known about the effects of daily muscle stretching on adaptations of endothelial function and muscle blood flow. The present study aimed to determine the effects of daily muscle stretching on endothelium-dependent vasodilatation and muscle blood flow in aged rats. The lower hindlimb muscles of aged Fischer rats were passively stretched by placing an ankle dorsiflexion splint for 30 min day -1 , 5 days week -1 , for 4 weeks. Blood flow to the stretched limb and the non-stretched contralateral limb was determined at rest and during treadmill exercise. Endothelium-dependent/independent vasodilatation was evaluated in soleus muscle arterioles. Levels of hypoxia-induced factor-1α, vascular endothelial growth factor A and neuronal nitric oxide synthase were determined in soleus muscle fibres. Levels of endothelial nitric oxide synthase and superoxide dismutase were determined in soleus muscle arterioles, and microvascular volume and capillarity were evaluated by microcomputed tomography and lectin staining, respectively. During exercise, blood flow to plantar flexor muscles was significantly higher in the stretched limb. Endothelium-dependent vasodilatation was enhanced in arterioles from the soleus muscle from the stretched limb. Microvascular volume, number of capillaries per muscle fibre, and levels of hypoxia-induced factor-1α, vascular endothelial growth

  13. Muscle Fiber Types and Training.

    ERIC Educational Resources Information Center

    Karp, Jason R.

    2001-01-01

    The specific types of fibers that make up individual muscles greatly influence how people will adapt to their training programs. This paper explains the complexities of skeletal muscles, focusing on types of muscle fibers (slow-twitch and fast-twitch), recruitment of muscle fibers to perform a motor task, and determining fiber type. Implications…

  14. Expiratory muscle loading increases intercostal muscle blood flow during leg exercise in healthy humans

    PubMed Central

    Athanasopoulos, Dimitris; Louvaris, Zafeiris; Cherouveim, Evgenia; Andrianopoulos, Vasilis; Roussos, Charis; Zakynthinos, Spyros

    2010-01-01

    We investigated whether expiratory muscle loading induced by the application of expiratory flow limitation (EFL) during exercise in healthy subjects causes a reduction in quadriceps muscle blood flow in favor of the blood flow to the intercostal muscles. We hypothesized that, during exercise with EFL quadriceps muscle blood flow would be reduced, whereas intercostal muscle blood flow would be increased compared with exercise without EFL. We initially performed an incremental exercise test on eight healthy male subjects with a Starling resistor in the expiratory line limiting expiratory flow to ∼ 1 l/s to determine peak EFL exercise workload. On a different day, two constant-load exercise trials were performed in a balanced ordering sequence, during which subjects exercised with or without EFL at peak EFL exercise workload for 6 min. Intercostal (probe over the 7th intercostal space) and vastus lateralis muscle blood flow index (BFI) was calculated by near-infrared spectroscopy using indocyanine green, whereas cardiac output (CO) was measured by an impedance cardiography technique. At exercise termination, CO and stroke volume were not significantly different during exercise, with or without EFL (CO: 16.5 vs. 15.2 l/min, stroke volume: 104 vs. 107 ml/beat). Quadriceps muscle BFI during exercise with EFL (5.4 nM/s) was significantly (P = 0.043) lower compared with exercise without EFL (7.6 nM/s), whereas intercostal muscle BFI during exercise with EFL (3.5 nM/s) was significantly (P = 0.021) greater compared with that recorded during control exercise (0.4 nM/s). In conclusion, increased respiratory muscle loading during exercise in healthy humans causes an increase in blood flow to the intercostal muscles and a concomitant decrease in quadriceps muscle blood flow. PMID:20507965

  15. The Drosophila indirect flight muscle myosin heavy chain isoform is insufficient to transform the jump muscle into a highly stretch-activated muscle type.

    PubMed

    Zhao, Cuiping; Swank, Douglas M

    2017-02-01

    Stretch activation (SA) is a delayed increase in force that enables high power and efficiency from a cyclically contracting muscle. SA exists in various degrees in almost all muscle types. In Drosophila, the indirect flight muscle (IFM) displays exceptionally high SA force production (F SA ), whereas the jump muscle produces only minimal F SA We previously found that expressing an embryonic (EMB) myosin heavy chain (MHC) isoform in the jump muscle transforms it into a moderately SA muscle type and enables positive cyclical power generation. To investigate whether variation in MHC isoforms is sufficient to produce even higher F SA , we substituted the IFM MHC isoform (IFI) into the jump muscle. Surprisingly, we found that IFI only caused a 1.7-fold increase in F SA , less than half the increase previously observed with EMB, and only at a high Pi concentration, 16 mM. This IFI-induced F SA is much less than what occurs in IFM, relative to isometric tension, and did not enable positive cyclical power generation by the jump muscle. Both isometric tension and F SA of control fibers decreased with increasing Pi concentration. However, for IFI-expressing fibers, only isometric tension decreased. The rate of F SA generation was ~1.5-fold faster for IFI fibers than control fibers, and both rates were Pi dependent. We conclude that MHC isoforms can alter F SA and hence cyclical power generation but that isoforms can only endow a muscle type with moderate F SA Highly SA muscle types, such as IFM, likely use a different or additional mechanism. Copyright © 2017 the American Physiological Society.

  16. [Muscle regeneration in mdx mouse, and a trial of normal myoblast transfer into regenerating dystrophic muscle].

    PubMed

    Takemitsu, M; Arahata, K; Nonaka, I

    1990-10-01

    The most ideal therapeutic trial on Duchenne muscular dystrophy (DMD) is a transfer of normal myoblasts into dystrophic muscle which has been attempted on animal models in several institutes. In the process of muscle regeneration, the transferred normal myoblasts are expected to incorporate into the regenerating fibers in host dystrophic mouse. To know the capacity of muscle regeneration in dystrophic muscle, we compared the regenerating process of the normal muscle with that of the dystrophic muscle after myonecrosis induced by 0.25% bupivacaine hydrochloride (BPVC) chronologically. In the present study, C57BL/10ScSn-mdx (mdx) mouse was used as an animal model of DMD and C57BL/10ScSn (B10) mouse as a control. There was no definite difference in the behavior of muscle fiber regeneration between normal and dystrophic muscles. The dystrophic muscle regenerated rapidly at the similar tempo to the normal as to their size and fiber type differentiation. The variation in fiber size diameter of dystrophic muscle, however, was more obvious than that of normal. To promote successful myoblast transfer from B10 mouse into dystrophic mdx mouse at higher ratio, cultured normal myoblasts were transferred into the regenerating dystrophic muscle on the first and the second day after myonecrosis induced by BPVC. Two weeks after the myoblast injection, the muscles were examined with immunohistochemical stain using anti dystrophin antibody. Although dystrophin-positive fibers appeared in dystrophic muscle, the positive fibers were unexpectedly small in number (3.86 +/- 1.50%).(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Group I Paks support muscle regeneration and counteract cancer-associated muscle atrophy.

    PubMed

    Cerquone Perpetuini, Andrea; Re Cecconi, Andrea David; Chiappa, Michela; Martinelli, Giulia Benedetta; Fuoco, Claudia; Desiderio, Giovanni; Castagnoli, Luisa; Gargioli, Cesare; Piccirillo, Rosanna; Cesareni, Gianni

    2018-05-21

    Skeletal muscle is characterized by an efficient regeneration potential that is often impaired during myopathies. Understanding the molecular players involved in muscle homeostasis and regeneration could help to find new therapies against muscle degenerative disorders. Previous studies revealed that the Ser/Thr kinase p21 protein-activated kinase 1 (Pak1) was specifically down-regulated in the atrophying gastrocnemius of Yoshida hepatoma-bearing rats. In this study, we evaluated the role of group I Paks during cancer-related atrophy and muscle regeneration. We examined Pak1 expression levels in the mouse Tibialis Anterior muscles during cancer cachexia induced by grafting colon adenocarcinoma C26 cells and in vitro by dexamethasone treatment. We investigated whether the overexpression of Pak1 counteracts muscle wasting in C26-bearing mice and in vitro also during interleukin-6 (IL6)-induced or dexamethasone-induced C2C12 atrophy. Moreover, we analysed the involvement of group I Paks on myogenic differentiation in vivo and in vitro using the group I chemical inhibitor IPA-3. We found that Pak1 expression levels are reduced during cancer-induced cachexia in the Tibialis Anterior muscles of colon adenocarcinoma C26-bearing mice and in vitro during dexamethasone-induced myotube atrophy. Electroporation of muscles of C26-bearing mice with plasmids directing the synthesis of PAK1 preserves fiber size in cachectic muscles by restraining the expression of atrogin-1 and MuRF1 and possibly by inducing myogenin expression. Consistently, the overexpression of PAK1 reduces the dexamethasone-induced expression of MuRF1 in myotubes and increases the phospho-FOXO3/FOXO3 ratio. Interestingly, the ectopic expression of PAK1 counteracts atrophy in vitro by restraining the IL6-Stat3 signalling pathway measured in luciferase-based assays and by reducing rates of protein degradation in atrophying myotubes exposed to IL6. On the other hand, we observed that the inhibition of group I Paks

  18. Sex Differences in Muscle Wasting.

    PubMed

    Anderson, Lindsey J; Liu, Haiming; Garcia, Jose M

    2017-01-01

    With aging and other muscle wasting diseases, men and women undergo similar pathological changes in skeletal muscle: increased inflammation, enhanced oxidative stress, mitochondrial dysfunction, satellite cell senescence, elevated apoptosis and proteasome activity, and suppressed protein synthesis and myocyte regeneration. Decreased food intake and physical activity also indirectly contribute to muscle wasting. Sex hormones also play important roles in maintaining skeletal muscle homeostasis. Testosterone is a potent anabolic factor promoting muscle protein synthesis and muscular regeneration. Estrogens have a protective effect on skeletal muscle by attenuating inflammation; however, the mechanisms of estrogen action in skeletal muscle are less well characterized than those of testosterone. Age- and/or disease-induced alterations in sex hormones are major contributors to muscle wasting. Hence, men and women may respond differently to catabolic conditions because of their hormonal profiles. Here we review the similarities and differences between men and women with common wasting conditions including sarcopenia and cachexia due to cancer, end-stage renal disease/chronic kidney disease, liver disease, chronic heart failure, and chronic obstructive pulmonary disease based on the literature in clinical studies. In addition, the responses in men and women to the commonly used therapeutic agents and their efficacy to improve muscle mass and function are also reviewed.

  19. Activation of plantar flexor muscles is constrained by multiple muscle synergies rather than joint torques

    PubMed Central

    Suzuki, Takahito; Kinugasa, Ryuta; Fukashiro, Senshi

    2017-01-01

    Behavioral evidence has suggested that a small number of muscle synergies may be responsible for activating a variety of muscles. Nevertheless, such dimensionality reduction may also be explained using the perspective of alternative hypotheses, such as predictions based on linear combinations of joint torques multiplied by corresponding coefficients. To compare the explanatory capacity of these hypotheses for describing muscle activation, we enrolled 12 male volunteers who performed isometric plantar flexor contractions at 10–100% of maximum effort. During each plantar flexor contraction, the knee extensor muscles were isometrically contracted at 0%, 50%, or 100% of maximum effort. Electromyographic activity was recorded from the vastus lateralis, medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus muscles and quantified using the average rectified value (ARV). At lower plantar flexion torque, regression analysis identified a clear linear relationship between the MG and soleus ARVs and between the MG and LG ARVs, suggesting the presence of muscle synergy (r2 > 0.65). The contraction of the knee extensor muscles induced a significant change in the slope of this relationship for both pairs of muscles (MG × soleus, P = 0.002; MG × LG, P = 0.006). Similarly, the slope of the linear relationship between the plantar flexion torque and the ARV of the MG or soleus changed significantly with knee extensor contraction (P = 0.031 and P = 0.041, respectively). These results suggest that muscle synergies characterized by non-mechanical constraints are selectively recruited according to whether contraction of the knee extensor muscles is performed simultaneously, which is relatively consistent with the muscle synergy hypothesis. PMID:29107958

  20. Respiratory muscle training increases respiratory muscle strength and reduces respiratory complications after stroke: a systematic review.

    PubMed

    Menezes, Kênia Kp; Nascimento, Lucas R; Ada, Louise; Polese, Janaine C; Avelino, Patrick R; Teixeira-Salmela, Luci F

    2016-07-01

    After stroke, does respiratory muscle training increase respiratory muscle strength and/or endurance? Are any benefits carried over to activity and/or participation? Does it reduce respiratory complications? Systematic review of randomised or quasi-randomised trials. Adults with respiratory muscle weakness following stroke. Respiratory muscle training aimed at increasing inspiratory and/or expiratory muscle strength. Five outcomes were of interest: respiratory muscle strength, respiratory muscle endurance, activity, participation and respiratory complications. Five trials involving 263 participants were included. The mean PEDro score was 6.4 (range 3 to 8), showing moderate methodological quality. Random-effects meta-analyses showed that respiratory muscle training increased maximal inspiratory pressure by 7 cmH2O (95% CI 1 to 14) and maximal expiratory pressure by 13 cmH2O (95% CI 1 to 25); it also decreased the risk of respiratory complications (RR 0.38, 95% CI 0.15 to 0.96) compared with no/sham respiratory intervention. Whether these effects carry over to activity and participation remains uncertain. This systematic review provided evidence that respiratory muscle training is effective after stroke. Meta-analyses based on five trials indicated that 30minutes of respiratory muscle training, five times per week, for 5 weeks can be expected to increase respiratory muscle strength in very weak individuals after stroke. In addition, respiratory muscle training is expected to reduce the risk of respiratory complications after stroke. Further studies are warranted to investigate whether the benefits are carried over to activity and participation. PROSPERO (CRD42015020683). [Menezes KKP, Nascimento LR, Ada L, Polese JC, Avelino PR, Teixeira-Salmela LF (2016) Respiratory muscle training increases respiratory muscle strength and reduces respiratory complications after stroke: a systematic review.Journal of Physiotherapy62: 138-144]. Copyright © 2016 Australian