Anti-GM2 gangliosides IgM paraprotein induces neuromuscular block without neuromuscular damage.

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Santafé, Manel M; Sabaté, M Mar; Garcia, Neus; Ortiz, Nico; Lanuza, M Angel; Tomàs, Josep

2008-11-15

We analyzed the effect on the mouse neuromuscular synapses of a human monoclonal IgM, which binds specifically to gangliosides with the common epitope [GalNAc beta 1-4Gal(3-2 alpha NeuAc)beta 1-]. We focused on the role of the complement. Evoked neurotransmission was partially blocked by IgM both acutely (1 h) and chronically (10 days). Transmission electron microscopy shows important nerve terminal growth and retraction remodelling though axonal injury can be ruled out. Synapses did not show mouse C5b-9 immunofluorescence and were only immunolabelled when human complement was added. Therefore, the IgM-induced synaptic changes occur without complement-mediated membrane attack.

Reversal of rocuronium-induced (1.2 mg kg-1) profound neuromuscular block by accidental high dose of sugammadex (40 mg kg-1).

NARCIS (Netherlands)

Molina, A.L.; Boer, H.D. de; Klimek, M.; Heeringa, M.; Klein, J.

2007-01-01

Sugammadex is the first selective relaxant binding agent and reverses rocuronium-induced neuromuscular block. A case is reported in which a patient accidentally received a high dose of sugammadex (40 mg kg-1) to reverse a rocuronium-induced (1.2 mg kg-1) profound neuromuscular block. A fast and

Dexamethasone Does Not Inhibit Sugammadex Reversal After Rocuronium-Induced Neuromuscular Block.

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Buonanno, Pasquale; Laiola, Anna; Palumbo, Chiara; Spinelli, Gianmario; Servillo, Giuseppe; Di Minno, Raffaele Maria; Cafiero, Tullio; Di Iorio, Carlo

2016-06-01

Sugammadex is a relatively new molecule that reverses neuromuscular block induced by rocuronium. The particular structure of sugammadex traps the cyclopentanoperhydrophenanthrene ring of rocuronium in its hydrophobic cavity. Dexamethasone shares the same steroidal structure with rocuronium. Studies in vitro have demonstrated that dexamethasone interacts with sugammadex, reducing its efficacy. In this study, we investigated the clinical relevance of this interaction and its influence on neuromuscular reversal. In this retrospective case-control study, we analyzed data from 45 patients divided into 3 groups: dexamethasone after induction group (15 patients) treated with 8 mg dexamethasone as an antiemetic drug shortly after induction of anesthesia; dexamethasone before reversal group (15 patients) treated with dexamethasone just before sugammadex injection; and control group (15 patients) treated with 8 mg ondansetron. All groups received 0.6 mg/kg rocuronium at induction, 0.15 mg/kg rocuronium at train-of-four ratio (TOF) 2 for neuromuscular relaxation, and 2 mg/kg sugammadex for reversal at the end of the procedure at TOF2. Neuromuscular relaxation was monitored with a TOF-Watch® system. The control group had a recovery time of 154 ± 54 seconds (mean ± SD), the dexamethasone after induction group 134 ± 55 seconds, and the dexamethasone before reversal group 131 ± 68 seconds. The differences among groups were not statistically significant (P = 0.5141). Our results show that the use of dexamethasone as an antiemetic drug for the prevention of postoperative nausea and vomiting does not interfere with reversal of neuromuscular blockade with sugammadex in patients undergoing elective surgery with general anesthesia in contrast to in vitro studies that support this hypothesis.

Preferences of Mexican anesthesiologists for vecuronium, rocuronium, or other neuromuscular blocking agents: a survey

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Garduño-Espinosa J

2002-05-01

Full Text Available Abstract Background Several neuromuscular blocking (NMB agents are available for clinical use in anesthesia. The present study was performed in order to identify preferences and behaviors of anesthesiologists for using vecuronium, rocuronium or other NMB agents in their clinical practice. Material and methods The cross-sectional survey was applied at the Updated Course of the Colegio Mexicano de Anestesiología performed last year. Of 989, 282 (28.5% surveys were returned. Results Most anesthesiologists were working at both public and private hospitals, performed anesthetic procedures for hospitalized and ambulatory patients, and anesthetized children as well as adults. Respondents did not consider mechanomyography as the gold standard method for neuromuscular monitoring. The T25 was not recognized as a pharmacodynamic parameter that represents the clinical duration of the neuromuscular block. Most answered that vecuronium induces less histamine release than rocuronium, had never used any neuromuscular monitor, did not know the cost of vecuronium and rocuronium, and preferred rocuronium in multiple-sampling vials and vecuronium in either a vial for single or multiple sampling. Rocuronium was preferred for emergency surgery in patients with full stomach only. Almost all of anesthesiologists that conserve the unused drug did it without refrigeration and more than 30% conserve the unused drug in one syringe for further use. Conclusion Vecuronium was preferred for most clinical situations, and the decision for this choice was not based on costs. Storage of unused drugs without refrigeration in a single syringe for purpose of future use in several patients represented a dangerous common practice.

A survey of the current use of neuromuscular blocking drugs among the Middle Eastern anesthesiologists

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Abdelazeem Eldawlatly

2013-01-01

Full Text Available Background: This survey aimed to assess the extent of practice of the Middle Eastern anesthesiologists in the use of neuromuscular blocking agents (NMB in 2012. Methods: We distributed an electronic survey among 577 members of the Triple-M Middle Eastern Yahoo anesthesia group, enquiring about their practice in the use of neuromuscular blocking agents. Questions concerned the routine "first choice" use of NMB, choice for tracheal intubation, the use of neuromuscular monitoring (NMT, type of NMB used in difficult airway, frequency of using suxamethonium, cisatracurium, rocuronium and sugammadex, observed side effects of rocuronium, residual curarization, and the reversal of residual curarization of rocuronium. Results: A total of 71 responses from 22 Middle Eastern institutions were collected. Most of the Middle Eastern anesthesiologists were using cisatracurium and rocuronium frequently for tracheal intubation (39% and 35%, respectively. From the respondents, 2/3 were using suxamethonium for tracheal intubation in difficult airway, 1/3 were using rocuronium routinely and 17% have observed hypersensitivity reactions to rocuronium, 54% reported residual curarization from rocuronium, 78% were routinely using neostigmine to reverse the rocuronium, 21% used sugammadex occasionally, and 35% were using NMT routinely during the use of NMB. Conclusions: We believe that more could be done to increase the awareness of the Middle Eastern anesthesiologists about the high incidence of PROC (>20% and the need for routine monitoring of neuromuscular function. This could be accomplished with by developing formal training programs and providing official guidelines.

A survey of the current use of neuromuscular blocking drugs among the Middle Eastern anesthesiologists.

Science.gov (United States)

Eldawlatly, Abdelazeem; El-Tahan, Mohamed R

2013-04-01

This survey aimed to assess the extent of practice of the Middle Eastern anesthesiologists in the use of neuromuscular blocking agents (NMB) in 2012. We distributed an electronic survey among 577 members of the Triple-M Middle Eastern Yahoo anesthesia group, enquiring about their practice in the use of neuromuscular blocking agents. Questions concerned the routine first choice use of NMB, choice for tracheal intubation, the use of neuromuscular monitoring (NMT), type of NMB used in difficult airway, frequency of using suxamethonium, cisatracurium, rocuronium and sugammadex, observed side effects of rocuronium, residual curarization, and the reversal of residual curarization of rocuronium. A total of 71 responses from 22 Middle Eastern institutions were collected. Most of the Middle Eastern anesthesiologists were using cisatracurium and rocuronium frequently for tracheal intubation (39% and 35%, respectively). From the respondents, 2/3 were using suxamethonium for tracheal intubation in difficult airway, 1/3 were using rocuronium routinely and 17% have observed hypersensitivity reactions to rocuronium, 54% reported residual curarization from rocuronium, 78% were routinely using neostigmine to reverse the rocuronium, 21% used sugammadex occasionally, and 35% were using NMT routinely during the use of NMB. We believe that more could be done to increase the awareness of the Middle Eastern anesthesiologists about the high incidence of PROC (>20%) and the need for routine monitoring of neuromuscular function. This could be accomplished with by developing formal training programs and providing official guidelines.

The influence of cold on the recovery of three neuromuscular blocking agents in man.

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England, A J; Wu, X; Richards, K M; Redai, I; Feldman, S A

1996-03-01

The Arrhenius hypothesis suggests that change in temperature has a less marked effect on the rate of physical processes than on biological reactions. We have investigated the process underlying recovery from neuromuscular block in man by studying the effect of cooling on the rate of recovery from depolarising and non-depolarising block. Vecuronium, rocuronium and decamethonium (C10) neuromuscular block were investigated using the isolated forearm technique on awake human volunteers. In these experiments, one arm was cooled whilst the other was used as control. Moderate hypothermia decreased the rate of recovery from all three agents, but this was significantly less marked with the depolarising drug. The mean Q10 (the anticipated change in rate of a reaction across of 10 degrees C temperature gradient) of the rate of recovery for vecuronium was 3.21, rocuronium 2.86 and decamethonium 1.29. This suggests a different process in the recovery of these two types of drug. According to the Arrhenius hypothesis this would suggest that the recovery from non-depolarising drugs is likely to involve a biochemical mechanism and that recovery from decamethonium is controlled by a physical process.

Influence of deep neuromuscular block on the surgeonś assessment of surgical conditions during laparotomy

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Madsen, M V; Scheppan, S; Mørk, E

2017-01-01

Background: During laparotomy, surgeons may experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. Deep neuromuscular block (NMB), defined as a post-tetanic-count (PTC) between 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesized th...

Reversal of rocuronium-induced neuromuscular block by sugammadex is independent of renal perfusion in anesthetized cats

NARCIS (Netherlands)

Staals, L.M.; Boer, H.D. de; Egmond, J. van; Hope, F.; Pol, F.M. van de; Bom, A.H.; Driessen, J.J.; Booij, L.H.D.J.

2011-01-01

PURPOSE: Sugammadex is a selective relaxant binding agent designed to encapsulate the aminosteroidal neuromuscular blocking agent rocuronium, thereby reversing its effect. Both sugammadex and the sugammadex-rocuronium complex are eliminated by the kidneys. This study investigated the effect of

Influence of deep neuromuscular block on the surgeonś assessment of surgical conditions during laparotomy

DEFF Research Database (Denmark)

Madsen, M V; Scheppan, S; Mørk, E

2017-01-01

Background: During laparotomy, surgeons may experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. Deep neuromuscular block (NMB), defined as a post-tetanic-count (PTC) between 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesized th...... time, occurrence of wound infection, and wound dehiscence were found. Conclusions: Deep NMB compared with standard NMB resulted in better subjective ratings of surgical conditions during laparotomy.......Background: During laparotomy, surgeons may experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. Deep neuromuscular block (NMB), defined as a post-tetanic-count (PTC) between 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesized...... that deep NMB (PTC 0-1) would improve subjective ratings of surgical conditions during upper laparotomy as compared with standard NMB. Methods: This was a double blinded, randomized study. A total of 128 patients undergoing elective upper laparotomy were randomized to either continuous deep NMB (infusion...

New way of dosing sugammadex for termination of vecuronium induced neuromuscular block

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Blaž Peček

2015-06-01

Full Text Available Background and Goal of Study: Sugammadex is a selective binding agent that bindsaminosteroid muscle relaxants. Each molecule of sugammadex binds one molecule of musclerelaxant. To produce the same depth of the neuromuscular block (NMB much less molecules ofvecuronium are needed than molecules of rocuronium. In theory less sugammadex would beneeded to neutralise the neuromuscular block if vecuronium was used to produce the neuromuscular block. Our aim was to compare reversal of vecuronium induced muscle relaxation between a new way of dosing sugammadex, which takes into account TOF value at the end of the surgery and the amount of vecuronium given during the surgery with neostigmine atropine combination. We also wanted to know how much this dosage regime can save compared to standard per kg dosage.Materials and Methods: 20 adult patients requiring a general anesthesia for surgery were analysed. The first group of 11 patients (SUG received sugammadex at the end of the surgery according to the table one for NMB reversal. The second group of 9 patients (NEO received neostigmine and atropine. Train of four (TOF value was recorded at the end of the surgery and then continuously until the TOF value reached more than 0.9 and the patient was extubated. The time required for the TOF value reaching 0.9 was compared between the groups. For economical evaluation we compared the amount of sugammadex used in the SUG group to standard sugammadex per kg dosage.Results and Discussion: Mean time to recovery to a TOF ratio of 0.9 with sugammadex was 5.12min versus 12.6 min with neostigmine atropine (P < 0.05. No sign of postoperative residual curarisation was observed in the SUG group. For patients in our study 530 mg of sugammadex were used to neutralise the NMB. If standard per kg sugammadex dosing had been used we would have used 2420 mg for the NMB reversal.Conclusion(s: New dosing for sugammadex was successful in neutralising the NMB regardlessof the TOF value

Train-of-four ratio recovery often precedes twitch recovery when neuromuscular block is reversed by sugammadex

NARCIS (Netherlands)

Staals, L.M.; Driessen, J.J.; Egmond, J. van; Boer, H.D. de; Klimek, M.; Flockton, E.A.; Snoeck, M.M.J.

2011-01-01

BACKGROUND: Sugammadex reverses rocuronium-induced neuromuscular block (NMB). In all published studies investigating sugammadex, the primary outcome parameter was a train-of-four (TOF) ratio of 0.9. The recovery time of T1 was not described. This retrospective investigation describes the recovery of

Neuromuscular blockade in children Bloqueadores neuromusculares em crianças

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João Fernando Lourenço de Almeida

2000-06-01

Full Text Available Neuromuscular blocking agents (NMBAs have been widely used to control patients who need to be immobilized for some kind of medical intervention, such as an invasive procedure or synchronism with mechanical ventilation. The purpose of this monograph is to review the pharmacology of the NMBAs, to compare the main differences between the neuromuscular junction in neonates, infants, toddlers and adults, and moreover to discuss their indications in critically ill pediatric patients. Continuous improvement of knowledge about NMBAs pharmacology, adverse effects, and the many other remaining unanswered questions about neuromuscular junction and neuromuscular blockade in children is essential for the correct use of these drugs. Therefore, the indication of these agents in pediatrics is determined with extreme judiciousness. Computorized (Medline 1990-2000 and active search of articles were the mechanisms used in this review.Os bloqueadores neuromusculares têm sido amplamente utilizados para controlar pacientes que necessitem imobilidade para algum tipo de intervenção médica, desde a realização de procedimentos invasivos até a obtenção de sincronismo com a ventilação mecânica. O objetivo básico desta monografia é revisar a farmacologia dos principais bloqueadores neuromusculares, analisar as diferenças existentes na junção neuromuscular de neonatos, lactentes, pré-escolares e adultos, além de discutir suas indicações em pacientes criticamente enfermos internados em unidade de terapia intensiva pediátrica. Revisão computadorizada da literatura (Medline 1990-2000 associado a busca ativa de artigos compuseram o mecanismo de busca dos dados desta revisão.

Effects of cardiac output on the onset of rocuronium-induced neuromuscular block in elderly patients.

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Shiraishi, Naoki; Aono, Mayu; Kameyama, Yasuhito; Yamamoto, Mai; Kitajima, Osamu; Suzuki, Takahiro

2018-05-21

The aim of this study was to elucidate the relationship between the onset of rocuronium-induced neuromuscular block and arterial pressure-based cardiac output (CO) in elderly patients. Forty elderly patients aged 65-83 years were enrolled in this study. After induction of anesthesia, contractions of the adductor pollicis muscle to ulnar nerve train-of-four stimulation were acceleromyographically evaluated and 1 mg/kg rocuronium was administered following CO measurement. The correlation between onset of rocuronium action and CO was analyzed. The mean [SD] CO reduced after induction of anesthesia from 5.1 [1.8] L/min to 3.8 [1.1] L/min. The onset time of rocuronium-induced neuromuscular block was 110.3 [23.9] s (range 60-165). There was a statistically significant inverse correlation between the onset time of rocuronium and CO [onset time (s) = - 13.2·CO + 159.7, R 2  = 0.376]. In the elderly, CO influences the onset of action of rocuronium.

Comparative effectiveness of Calabadion and sugammadex to reverse non-depolarizing neuromuscular blocking agents

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Haerter, Friederike; Simons, Jeroen Cedric Peter; Foerster, Urs; Duarte, Ingrid Moreno; Diaz-Gil, Daniel; Ganapati, Shweta; Eikermann-Haerter, Katharina; Ayata, Cenk; Zhang, Ben; Blobner, Manfred; Isaacs, Lyle; Eikermann, Matthias

2015-01-01

Background We evaluated the comparative effectiveness of calabadion 2 to reverse non-depolarizing neuromuscular blocking agents (NMBAs) by binding and inactivation. Methods The dose-response relationship of drugs to reverse vecuronium, rocuronium, and cisatracurium-induced neuromuscular block (NMB) was evaluated in vitro (competition binding assays and urine analysis), ex vivo (n=34; phrenic nerve hemidiaphragm preparation) and in vivo (n=108; quadriceps femoris muscle of the rat). Cumulative dose-response curves of calabadions, neostigmine, or sugammadex were created ex vivo at steady-state deep NMB. In living rats, we studied the dose-response relationship of the test drugs to reverse deep block under physiological conditions and we measured the amount of calabadion 2 excreted in the urine. Results In vitro experiments showed that calabadion 2 binds rocuronium with 89 times the affinity of sugammadex (Ka = 3.4 × 109 M−1 and Ka = 3.8 × 107 M−1). Urine analysis (proton nuclear magnetic resonance), competition binding assays and ex vivo study results obtained in the absence of metabolic deactivation are in accordance with an 1:1 binding ratio of sugammadex and calabadion 2 toward rocuronium. In living rats, calabadion 2 dose-dependently and rapidly reversed all NMBAs tested. The molar potency of calabadion 2 to reverse vecuronium and rocuronium was higher compared to sugammadex. Calabadion 2 was eliminated renally, and did not affect blood pressure or heart rate. Conclusion Calabadion 2 reverses NMB-induced by benzylisoquinolines and steroidal NMBAs in rats more effectively, i.e. faster, than sugammadex. Calabadion 2 is eliminated in the urine and well tolerated in rats. PMID:26418697

Sensitivity to Rocuronium-Induced Neuromuscular Block and Reversibility with Sugammadex in a Patient with Myotonic Dystrophy

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Akihiro Kashiwai

2012-01-01

Full Text Available We report a patient with myotonic dystrophy who showed prolonged rocuronium-induced neuromuscular blockade, although with a fast recovery with sugammadex. During general anesthesia with propofol and remifentanil, the times to spontaneous recovery of the first twitch (T1 of train of four to 10% of control values after an intubating dose of rocuronium 1 mg/kg and an additional dose of 0.2 mg/kg were 112 min and 62 min, respectively. Despite the high sensitivity to rocuronium, sugammadex 2 mg/kg administered at a T1 of 10% safely and effectively antagonized rocuronium-induced neuromuscular block in 90 s.

Bloqueio neuromuscular prolongado após administração de mivacúrio: relato de caso Bloqueo neuromuscular prolongado después de administración de mivacúrio: relato de caso Prolonged neuromuscular block after mivacurium: case report

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Karina Bernardi Pimenta

2005-10-01

scheduled for outpatient procedure presenting prolonged neuromuscular block after mivacurium. Diagnosis was confirmed by low plasma cholinesterase activity. CONCLUSIONS: Preoperative laboratory screening, even including plasma cholinesterase activity testing, will not prevent the possibility of prolonged neuromuscular block due to possible qualitative enzymatic activity abnormality, and there is no recommendation for its systematic investigation. In the presence of this complication, patient should be sedated and maintained under mechanical ventilation until total muscle strength recovery. Laboratory tests should be requested for final diagnosis. It is the anesthesiologist’s duty to collect blood samples for quantitative and qualitative plasma cholinesterase tests. Patient and relatives should be counseled about the importance of the investigation to classify the atypical variant of plasma cholinesterase and its anesthetic complications.

Sugammadex and neostigmine dose-finding study for reversal of residual neuromuscular block at a train-of-four ratio of 0.2 (SUNDRO20)†,.

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Kaufhold, N; Schaller, S J; Stäuble, C G; Baumüller, E; Ulm, K; Blobner, M; Fink, H

2016-02-01

The aim of this dose-finding study was to evaluate the dose-response relationship of sugammadex and neostigmine to reverse a commonly observed level of incomplete recovery from rocuronium-induced neuromuscular block, that is, a train-of-four ratio (TOFR) ≥0.2. Ninety-nine anaesthetized patients received rocuronium 0.6 mg kg(-1) i.v. for tracheal intubation and, if necessary, incremental doses of 0.1-0.2 mg kg(-1). Neuromuscular monitoring was performed by calibrated electromyography. Once the TOFR recovered to 0.2, patients were randomized to receive sugammadex (0.25, 0.5, 0.75, 1.0, or 1.25 mg kg(-1) i.v.), neostigmine (10, 25, 40, 55, or 70 µg kg(-1) i.v.), or saline (n=9 per group). Primary and secondary end points were the doses necessary to restore neuromuscular function to a TOFR≥0.9 with an upper limit of 5 and 10 min for 95% of patients, respectively. Neostigmine was not able to fulfil the end points. Based on the best-fitting model, the sugammadex dose estimation for recovery to a TOFR≥0.9 for 95% of patients within 5 and 10 min was 0.49 and 0.26 mg kg(-1), respectively. A residual neuromuscular block of a TOFR of 0.2 cannot be reversed reliably with neostigmine within 10 min. In the conditions studied, substantially lower doses of sugammadex than the approved dose of 2.0 mg kg(-1) may be sufficient to reverse residual rocuronium-induced neuromuscular block at a recovery of TOFR≥0.2. NCT01006720. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Prolongation of rapacuronium neuromuscular blockade by clindamycin and magnesium.

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Sloan, Paul A; Rasul, Mazhar

2002-01-01

We report a prolonged neuromuscular block with the nondepolarizing muscle relaxant rapacuronium in the presence of clindamycin. Even when using "short-acting" muscle relaxants, the anesthesiologist must routinely monitor the neuromuscular function.

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

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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 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 sugammadex (P�

Improving Neuromuscular Monitoring and Reducing Residual Neuromuscular Blockade With E-Learning

DEFF Research Database (Denmark)

Thomsen, Jakob Louis Demant; Mathiesen, Ole; Hägi-Pedersen, Daniel

2017-01-01

neuromuscular blockade in surgical patients at 6 Danish teaching hospitals. METHODS: In this interrupted time series study, we are collecting data repeatedly, in consecutive 3-week periods, before and after the intervention, and we will analyze the effect using segmented regression analysis. Anesthesia...... and an increased risk of respiratory complications. Use of an objective neuromuscular monitoring device may prevent residual block. Despite this, many anesthetists refrain from using the device. Efforts to increase the use of objective monitoring are time consuming and require the presence of expert personnel...... practice, and patient outcomes. The primary outcome is use of neuromuscular monitoring in patients according to the type of muscle relaxant received. Secondary outcomes include last recorded train-of-four value, administration of reversal agents, and time to discharge from the postanesthesia care unit...

Recovery characteristics of patients receiving either sugammadex or neostigmine and glycopyrrolate for reversal of neuromuscular block: a randomised controlled trial.

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Paech, M J; Kaye, R; Baber, C; Nathan, E A

2018-03-01

Sugammadex more rapidly and reliably reverses rocuronium-induced neuromuscular block compared with neostigmine, but it is not known if subsequent patient outcomes, including nausea, vomiting and other aspects of recovery are modified. In this study, we compared the recovery characteristics of sugammadex and neostigmine/glycopyrrolate following reversal of neuromuscular block. This was a single-centre, randomised, blinded, parallel-group clinical trial in women undergoing elective day-surgical laparoscopic gynaecological surgery, with a standardised general anaesthesia regimen that included rocuronium. Neuromuscular block was reversed with either sugammadex 2 mg.kg -1 or neostigmine 40 μg.kg -1 and glycopyrrolate 400 μg. The primary outcome was the incidence of nausea and vomiting during the first six postoperative hours. Secondary outcomes included other measures of postoperative recovery such as patient symptoms and recovery scores. Three-hundred and four women were analysed by intention-to-treat (sugammadex n = 151, neostigmine n = 153), which included four major protocol violations. There was no significant difference between sugammadex and neostigmine groups in the incidence of early nausea and vomiting (49.0% vs. 51.0%, respectively; OR 0.92, 95%CI 0.59-1.45; p = 0.731). Double vision (11.5% vs. 20.0%; p = 0.044) and dry mouth (71.6% vs. 85.5%; p = 0.003) were less common after sugammadex. Sedation scores at 2 h were also lower after sugammadex (median (IQR [range]) 0 (0-3 [0-10]) vs. 2 (0-4.[0-10]); p = 0.021). Twenty-four-hour recovery scores were not significantly different between groups. Reversal with sugammadex in this patient population did not reduce postoperative nausea or vomiting compared with neostigmine/glycopyrrolate. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

Sugammadex given for rocuronium-induced neuromuscular blockade in infants: a retrospectıve study.

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Ozmete, Ozlem; Bali, Cagla; Cok, Oya Yalcin; Turk, Hatice Evren Eker; Ozyilkan, Nesrın Bozdogan; Civi, Soner; Aribogan, Anıs

2016-12-01

To evaluate the efficacy and safety of sugammadex in reversing profound neuromuscular block induced by rocuronium in infant patients. Retrospective observational study. University teaching hospital. Twenty-six infants (2-12 months of age; 3-11 kg) with an American Society of Anesthesiologists classification I, II, or III who were scheduled to undergo neurosurgical procedures were included in the study. Anesthesia was induced with 5 mg/kg thiopental, 1 μg/kg fentanyl and 0.6 mg/kg rocuronium. Sevoflurane was administered to all patients after intubation. The neuromuscular block was monitored with acceleromyography using train-of-four (TOF) stimuli. Patients received additional doses of rocuronium to maintain a deep block during surgery. If profound neuromuscular block (TOF, 0) persisted at the end of the surgery, 3mg/kg sugammadex was administered. The demographic data, surgeries, and anesthetic agents were recorded. The time from sugammadex administration to recovery of neuromuscular function (TOF ratio, >0.9) and complications during and after extubation were also recorded. Twenty-six infants who had a deep neuromuscular block (TOF, 0) at the end of surgery received 3 mg/kg sugammadex. The mean recovery time of the T4/T1 ratio of 0.9 was 112 seconds. No clinical evidence of recurarization or residual curarization was observed. The efficacy and safety of sugammadex were confirmed in infant surgical patients for reversal of deep neuromuscular block induced by rocuronium. Copyright © 2016 Elsevier Inc. All rights reserved.

Reversal with sugammadex for rocuronium-induced deep neuromuscular block after pretreatment of magnesium sulfate in rabbits.

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Kang, Woon Seok; Kim, Kyo Sang; Song, Shin Mi

2017-04-01

Magnesium sulfate (MgSO 4 ) has been used in the treatment of pre-eclampsia, hypertension and arrhythmia. Magnesium enhances the neuromuscular block of rocuronium. This study has been conducted to evaluate the reversal efficacy of sugammadex from deep rocuronium-induced neuromuscular block (NMB) during consistent pretreatment of MgSO 4 in rabbits. Twenty-eight rabbits were randomly assigned to four groups, a control group or study groups (50% MgSO 4 150-200 mg/kg and 25 mg/kg/h IV), and received rocuronium 0.6 mg/kg. When post-tetanic count 1-2 appeared, sugammadex 2, 4, and 8 mg/kg was administered in the 2-mg group, control and 4-mg group, and 8-mg group, respectively. The recovery course after reversal of sugammadex administration was evaluated in each group. The mean serum concentration of magnesium was maintained at more than 2 mmol/L in the study groups, and the total dose of MgSO 4 was more than 590 mg. The reversal effect of sugammadex on rocuronium-induced NMB in pretreated MgSO 4 was not different from that in the group without MgSO 4 . The recovery time to train-of-four ratio 0.9 after sugammadex administration in the 2-mg group was longer than in the other groups (P rocuronium-induced NMB during large pretreatment of MgSO 4 was not affected. However, we should consider that the reversal effect of sugammadex varied depending on the dose.

Efficacy and safety of sugammadex versus neostigmine in reversing neuromuscular blockade in adults

DEFF Research Database (Denmark)

Hristovska, Ana-Marija; Duch, Patricia; Allingstrup, Mikkel

2017-01-01

, and undesirable autonomic responses. Sugammadex is a selective relaxant-binding agent specifically developed for rapid reversal of non-depolarizing neuromuscular blockade induced by rocuronium. Its potential clinical benefits include fast and predictable reversal of any degree of block, increased patient safety......, reduced incidence of residual block on recovery, and more efficient use of healthcare resources. OBJECTIVES: The main objective of this review was to compare the efficacy and safety of sugammadex versus neostigmine in reversing neuromuscular blockade caused by non-depolarizing neuromuscular agents......-depolarizing neuromuscular blocking agents for an elective in-patient or day-case surgical procedure. We included all trials comparing sugammadex versus neostigmine that reported recovery times or adverse events. We included any dose of sugammadex and neostigmine and any time point of study drug administration. DATA...

THE PHARMACODYNAMICS AND PHARMACOKINETICS OF ORG-9426, A NEW NONDEPOLARIZING NEUROMUSCULAR BLOCKING-AGENT, IN PATIENTS ANESTHETIZED WITH NITROUS-OXIDE, HALOTHANE AND FENTANYL

NARCIS (Netherlands)

WIERDA, JMKH; KLEEF, UW; LAMBALK, LM; KLOPPENBURG, WD; AGOSTON, S

The pharmacodynamics and pharmacokinetics of a new non-depolarizing neuromuscular blocking agent, Org 9426, were investigated. Ten patients undergoing elective head and neck surgery and anaesthetized with nitrous oxide, halothane and fentanyl, received a bolus dose of Org 9426 (1 mg.kg-1, 3 x ED90).

Serial elongation, derotation and flexion (EDF) casting under general anesthesia and neuromuscular blocking drugs improve outcome in patients with juvenile scoliosis: preliminary results.

Science.gov (United States)

Canavese, Federico; Botnari, Alexei; Dimeglio, Alain; Samba, Antoine; Pereira, Bruno; Gerst, Adeline; Granier, Marie; Rousset, Marie; Dubousset, Jean

2016-02-01

Juvenile scoliosis (JS), among different types of spinal deformity, remains still a challenge for orthopedic surgeons. Elongation, derotation and flexion (EDF) casting technique is a custom-made thoracolumbar cast based on a three-dimensional correction concept. The primary objective of the present study was to measure changes on plain radiographs of patients with JS treated with EDF plaster technique. The second aim was to evaluate the effectiveness of the EDF plaster technique realized under general anesthesia (GA) and neuromuscular blocking drugs, i.e. curare, on the radiological curve correction. A retrospective comparative case series study was performed in which were included forty-four skeletally immature patients. Three patient groups were selected. Group 1: EDF cast applied with patients awaken and no anesthesia; Group 2: EDF cast applied under GA without neuromuscular blocking drugs; Group 3: EDF cast applied under GA with neuromuscular blocking drugs. All the patients were treated with two serial EDF casts by 2 months and a half each. All measurements were taken from the radiographic exams. Cobb's angle; RVAD and Nash and Moe grade of rotation were assessed before and after applying the cast. Thirty-four (77.3 %) patients were followed up at least 24 months after removal of last EDF cast. Eighteen patients (3 males, 15 females) were included in Group 1, 12 (2 males, 10 females) in Group 2 and 14 (5 males, 9 females) in Group 3. Serial EDF casting was more effective at initial curve reduction and in preventing curve progression when applied under GA with neuromuscular blocking drugs, i.e. curare. RVAD and Nash and Moe score improved significantly in all groups of patients treated according to principles of EDF technique. During follow-up period, six patients required surgery in Group 1 (6/18; 33.3 %), 3 patients required surgery in Group 2 (3/12; 25 %) and 2 patients underwent surgery in Group 3 (2/14; 15 %). Preliminary results show EDF casting is

Sugammadex: A Review of Neuromuscular Blockade Reversal.

Science.gov (United States)

Keating, Gillian M

2016-07-01

Sugammadex (Bridion(®)) is a modified γ-cyclodextrin that reverses the effect of the steroidal nondepolarizing neuromuscular blocking agents rocuronium and vecuronium. Intravenous sugammadex resulted in rapid, predictable recovery from moderate and deep neuromuscular blockade in patients undergoing surgery who received rocuronium or vecuronium. Recovery from moderate neuromuscular blockade was significantly faster with sugammadex 2 mg/kg than with neostigmine, and recovery from deep neuromuscular blockade was significantly faster with sugammadex 4 mg/kg than with neostigmine or spontaneous recovery. In addition, recovery from neuromuscular blockade was significantly faster when sugammadex 16 mg/kg was administered 3 min after rocuronium than when patients spontaneously recovered from succinylcholine. Sugammadex also demonstrated efficacy in various special patient populations, including patients with pulmonary disease, cardiac disease, hepatic dysfunction or myasthenia gravis and morbidly obese patients. Intravenous sugammadex was generally well tolerated. In conclusion, sugammadex is an important option for the rapid reversal of rocuronium- or vecuronium-induced neuromuscular blockade.

Neuromuscular blockade in cardiac surgery: An update for clinicians

Directory of Open Access Journals (Sweden)

Hemmerling Thomas

2008-01-01

Full Text Available There have been great advancements in cardiac surgery over the last two decades; the widespread use of off-pump aortocoronary bypass surgery, minimally invasive cardiac surgery, and robotic surgery have also changed the face of cardiac anaesthesia. The concept of "Fast-track anaesthesia" demands the use of nondepolarising neuromuscular blocking drugs with short duration of action, combining the ability to provide (if necessary sufficiently profound neuromuscular blockade during surgery and immediate re-establishment of normal neuromuscular transmission at the end of surgery. Postoperative residual muscle paralysis is one of the major hurdles for immediate or early extubation after cardiac surgery. Nondepolarising neuromuscular blocking drugs for cardiac surgery should therefore be easy to titrate, of rapid onset and short duration of action with a pathway of elimination independent from hepatic or renal dysfunction, and should equally not affect haemodynamic stability. The difference between repetitive bolus application and continuous infusion is outlined in this review, with the pharmacodynamic and pharmacokinetic characteristics of vecuronium, pancuronium, rocuronium, and cisatracurium. Kinemyography and acceleromyography are the most important currently used neuromuscular monitoring methods. Whereas monitoring at the adductor pollicis muscle is appropriate at the end of surgery, monitoring of the corrugator supercilii muscle better reflects neuromuscular blockade at more central, profound muscles, such as the diaphragm, larynx, or thoraco-abdominal muscles. In conclusion, cisatracurium or rocuronium is recommended for neuromuscular blockade in modern cardiac surgery.

Neuromuscular Activity of Micrurus laticollaris (Squamata: Elapidae Venom in Vitro

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Alejandro Carbajal-Saucedo

2014-01-01

Full Text Available In this work, we have examined the neuromuscular activity of Micrurus laticollaris (Mexican coral snake venom (MLV in vertebrate isolated nerve-muscle preparations. In chick biventer cervicis preparations, the MLV induced an irreversible concentration- and time-dependent (1–30 µg/mL neuromuscular blockade, with 50% blockade occurring between 8 and 30 min. Muscle contractures evoked by exogenous acetylcholine were completely abolished by MLV, whereas those of KCl were also significantly altered (86% ± 11%, 53% ± 11%, 89% ± 5% and 89% ± 7% for one, three, 10 and 30 µg of venom/mL, respectively; n = 4; p < 0.05. In mouse phrenic nerve-diaphragm preparations, MLV (1–10 µg/mL promoted a slight increase in the amplitude of twitch-tension (3 µg/mL, followed by neuromuscular blockade (n = 4; the highest concentration caused complete inhibition of the twitches (time for 50% blockade = 26 ± 3 min, without exhibiting a previous neuromuscular facilitation. The venom (3 µg/mL induced a biphasic modulation in the frequency of miniature end-plate potentials (MEPPs/min, causing a significant increase after 15 min, followed by a decrease after 60 min (from 17 ± 1.4 (basal to 28 ± 2.5 (t15 and 12 ± 2 (t60. The membrane resting potential of mouse diaphragm preparations pre-exposed or not to d-tubocurarine (5 µg/mL was also significantly less negative with MLV (10 µg/mL. Together, these results indicate that M. laticollaris venom induces neuromuscular blockade by a combination of pre- and post-synaptic activities.

Stunted PFC activity during neuromuscular control under stress with obesity.

Science.gov (United States)

Mehta, Ranjana K

2016-02-01

Obesity is an established risk factor for impaired cognition, which is primarily regulated by the prefrontal cortex (PFC). However, very little is known about the neural pathways that underlie obesity-related declines in neuromuscular control, particularly under stress. The purpose of this study was to determine the role of the PFC on neuromuscular control during handgrip exertions under stress with obesity. Twenty non-obese and obese young adults performed submaximal handgrip exertions in the absence and presence of a concurrent stressful task. Primary dependent measures included oxygenated hemoglobin (HbO2: a measure of PFC activity) and force fluctuations (an indicator of neuromuscular control). Higher HbO2 levels in the PFC were observed in the non-obese compared to the obese group (P = 0.009). In addition, higher HbO2 levels were observed in the stress compared to the control condition in the non-obese group; however, this trend was reversed in the obese group (P = 0.043). In general, force fluctuations increased by 26% in the stress when compared to the control condition (P = 0.001) and obesity was associated with 39% greater force fluctuation (P = 0.024). Finally, while not significant, obesity-related decrements in force fluctuations were magnified under stress (P = 0.063). The current study provides the first evidence that neuromuscular decrements with obesity were associated with impaired PFC activity and this relationship was augmented in stress conditions. These findings are important because they provide new information on obesity-specific changes in brain function associated with neuromuscular control since the knowledge previously focused largely on obesity-specific changes in peripheral muscle capacity.

Neutralization Of The Neuromuscular Inhibition Of Venom And Taipoxin From The Taipan (oxyuranus Scutellatus) By F(ab ') 2 And Whole Igg Antivenoms

OpenAIRE

Herrera; Maria; de O Collaco; Rita de Cassia; Villalta; Mauren; Segura; Alvaro; Vargas; Mariangela; Wright; Christine E.; Paiva; Owen K.; Matainaho; Teatulohi; Jensen; Simon D.; Leon; Guillermo; Williams; David J.; Rodrigues-Simioni; Lea; Maria Gutierrez; Jose

2016-01-01

The neuromuscular junction activity of Oxyuranus scutellatus venom and its presynaptic neurotoxin, taipoxin, and their neutralization by two antivenoms were examined in mouse phrenic nerve-diaphragm preparations. The action of taipoxin was also studied at 21 degrees C. The efficacy of the antivenoms was also assessed in an in vivo mouse model. Both antivenoms were effective in neutralizing the neuromuscular blocking activity in preincubation-type experiments. In experiments involving independ...

Classification of neuromuscular blocking agents in a new neuromuscular preparation of the chick in vitro

NARCIS (Netherlands)

Riezen, H. van

1968-01-01

A neuromuscular preparation of the chick is described: 1. 1. The sciatic nerve-tibilis anterior muscle preparation of the 2–10 days old chick fulfils all criteria of an assay preparation and differentiates between curare-like and decamethonium-like agents. 2. 2. The preparation responds to

Neuromuscular transmission: new concepts and agents.

NARCIS (Netherlands)

Boer, H.D. de

2009-01-01

Sugammadex is the first selective relaxant binding agent which was originally designed to reverse the steroidal NMB drug rocuronium. The results of recent studies demonstrate that sugammadex is effective for reversal of rocuronium and vecuronium-induced neuromuscular block without apparent

Sugammadex Improves Neuromuscular Function in Patients ...

African Journals Online (AJOL)

2018-02-23

Feb 23, 2018 ... aminoglycosides), history of allergy to neuromuscular blocking agents, opioids or other drugs, and alcohol and drug dependence. Patients were divided into two ... titration microcalorimetry investigated the likelihood of the formation of complexes between sugammadex and other steroidal and nonsteroidal ...

Neutralization of the neuromuscular inhibition of venom and taipoxin from the taipan (Oxyuranus scutellatus) by F(ab0)2 and whole IgG antivenoms

OpenAIRE

Herrera Vega, María; de Cássia de O. Collaço, Rita; Villalta, Mauren; Segura Ruiz, Álvaro; Vargas Arroyo, Mariángela; Wright, Christine E.; Paiva, Owen K.; Matainaho, Teatulohi; Jensen, Simon D.; León Montero, Guillermo; Williams, David J.; Rodrigues Simioni, Lea; Gutiérrez, José María

2016-01-01

The neuromuscular junction activity of Oxyuranus scutellatus venom and its presynaptic neurotoxin, taipoxin, and their neutralization by two antivenoms were examined in mouse phrenic nerve-diaphragm preparations. The action of taipoxin was also studied at 21 °C. The efficacy of the antivenoms was also assessed in an in vivo mouse model. Both antivenoms were effective in neutralizing the neuromuscular blocking activity in preincubation-type experiments. In experiments involving independent add...

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.

Science.gov (United States)

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

Neuromuscular blockade in the elderly patient

Directory of Open Access Journals (Sweden)

Lee LA

2016-06-01

Full Text Available Luis A Lee, Vassilis Athanassoglou, Jaideep J Pandit Nuffield Department of Anaesthetics, Oxford University Hospitals NHS Foundation Trust, Oxford, UK Abstract: Neuromuscular blockade is a desirable or even essential component of general anesthesia for major surgical operations. As the population continues to age, and more operations are conducted in the elderly, due consideration must be given to neuromuscular blockade in these patients to avoid possible complications. This review considers the pharmacokinetics and pharmacodynamics of neuromuscular blockade that may be altered in the elderly. Compartment distribution, metabolism, and excretion of drugs may vary due to age-related changes in physiology, altering the duration of action with a need for reduced dosage (eg, aminosteroids. Other drugs (atracurium, cisatracurium have more reliable duration of action and should perhaps be considered for use in the elderly. The range of interpatient variability that neuromuscular blocking drugs may exhibit is then considered and drugs with a narrower range, such as cisatracurium, may produce more predictable, and inherently safer, outcomes. Ultimately, appropriate neuromuscular monitoring should be used to guide the administration of muscle relaxants so that the risk of residual neuromuscular blockade postoperatively can be minimized. The reliability of various monitoring is considered. This paper concludes with a review of the various reversal agents, namely, anticholinesterase drugs and sugammadex, and the alterations in dosing of these that should be considered for the elderly patient. Keywords: anesthesia, elderly, drugs, pharmacokinetics, pharmacodynamics 

Sugammadex, a Neuromuscular Blockade Reversal Agent, Causes Neuronal Apoptosis in Primary Cultures

Science.gov (United States)

Palanca, José M.; Aguirre-Rueda, Diana; Granell, Manuel V.; Aldasoro, Martin; Garcia, Alma; Iradi, Antonio; Obrador, Elena; Mauricio, Maria Dolores; Vila, Jose; Gil-Bisquert, Anna; Valles, Soraya L.

2013-01-01

Sugammadex, a γ-cyclodextrin that encapsulates selectively steroidal neuromuscular blocking agents, such as rocuronium or vecuronium, has changed the face of clinical neuromuscular pharmacology. Sugammadex allows a rapid reversal of muscle paralysis. Sugammadex appears to be safe and well tolerated. Its blood-brain barrier penetration is poor (Sugammadex in neurons in primary culture. Here we show that clinically relevant sugammadex concentrations cause apoptotic/necrosis neuron death in primary cultures. Studies on the underlying mechanism revealed that sugammadex-induced activation of mitochondria-dependent apoptosis associates with depletion of neuronal cholesterol levels. Furthermore SUG increase CytC, AIF, Smac/Diablo and CASP-3 protein expression in cells in culture. Potential association of SUG-induced alteration in cholesterol homeostasis with oxidative stress and apoptosis activation occurs. Furthermore, resistance/sensitivity to oxidative stress differs between neuronal cell types. PMID:23983586

A new approach to anesthesia management in myasthenia gravis: reversal of neuromuscular blockade by sugammadex.

NARCIS (Netherlands)

Boer, H.D. de; Egmond, J. van; Driessen, J.J.; Booij, L.H.D.J.

2010-01-01

A neuromuscular blocking drug (NMBD) induced neuromuscular blockade (NMB) in patients with myasthenia gravis usually dissipates either spontaneously or by administration of neostigmine. We administered sugammadex to a patient with myasthenia gravis to reverse a rocuronium-induced profound NMB. NMBDs

Impaired voluntary neuromuscular activation limits muscle power in mobility-limited older adults

Science.gov (United States)

Background. Age-related alterations of neuromuscular activation may contribute to deficits in muscle power and mobility function. This study assesses whether impaired activation of the agonist quadriceps and antagonist hamstrings, including amplitude- and velocity-dependent characteristics of activa...

Efficacy and safety of sugammadex in the reversal of deep neuromuscular blockade induced by rocuronium in patients with end-stage renal disease: A comparative prospective clinical trial.

Science.gov (United States)

de Souza, Camila M; Tardelli, Maria A; Tedesco, Helio; Garcia, Natalia N; Caparros, Mario P; Alvarez-Gomez, Jose A; de Oliveira Junior, Itamar S

2015-10-01

Renal failure affects the pharmacology of nondepolarizing neuromuscular blockers making recovery of neuromuscular function unpredictable. Sugammadex antagonises rocuronium-induced neuromuscular blockade by encapsulating rocuronium, creating a stable complex molecule that is mainly excreted by the kidneys. Previous studies suggest that sugammadex is effective in reversing moderate neuromuscular block in the presence of renal failure, but no data are available regarding reversal of profound neuromuscular block in patients with renal failure. The objective of this study is to compare the efficacy and safety of sugammadex in reversing profound neuromuscular block induced by rocuronium in patients with end-stage renal disease and those with normal renal function. A prospective clinical trial. Two university hospitals, from 1 October 2011 to 31 January 2012. Forty patients undergoing kidney transplant: 20 with renal failure [creatinine clearance (ClCr) 90 ml min). Neuromuscular monitoring was performed by acceleromyography and train-of-four (TOF) stimulation. Profound neuromuscular block (posttetanic count, one to three responses) was maintained during surgery. Sugammadex 4 mg kg was administered on completion of skin closure. Recovery of the TOF ratio to 0.9 was recorded. Monitoring of neuromuscular function continued in the postanesthesia care unit for a further 2 h. The efficacy of sugammadex was evaluated by the time taken for the TOF ratio to recover to 0.9. The safety of sugammadex was assessed by monitoring for recurrence of neuromuscular block every 15 min for 2 h. Secondary variables were time to recovery of TOF ratio to 0.7 and 0.8. After sugammadex administration, the mean time for recovery of the TOF ratio to 0.9 was prolonged in the renal failure group (5.6 ± 3.6 min) compared with the control group (2.7 ± 1.3 min, P = 0.003). No adverse events or evidence of recurrence of neuromuscular block were observed. In patients with

Influence of preoperative oral rehydration on arterial plasma rocuronium concentrations and neuromuscular blocking effects: A randomised controlled trial.

Science.gov (United States)

Ishigaki, Sayaka; Ogura, Takahiro; Kanaya, Ayana; Miyake, Yu; Masui, Kenichi; Kazama, Tomiei

2017-01-01

The influence of preoperative rehydration on the action of rocuronium has not yet been investigated. The objective is to evaluate the hypothesis that preoperative rehydration lowers arterial rocuronium plasma concentrations and changes its associated neuromuscular blocking effects during induction of anaesthesia. Randomised, single-blinded study. A secondary hospital from October 2013 to July 2014. In total, 46 men undergoing elective surgery were eligible to participate and were randomly allocated into two groups. Exclusion criteria were severe hepatic, renal or cardiovascular disorder; neuromuscular disease; history of allergy to rocuronium; BMI more than 30 kg m; receiving medication known to influence neuromuscular function. Participants received 1500 ml of oral rehydration solution (rehydration group) or none (control group) until 2 hours before anaesthesia. Arterial blood samples were obtained 60, 90 and 120 s and 30 min after rocuronium (0.6 mg kg) administration during total intravenous anaesthesia. Responses to 0.1-Hz twitch stimuli were measured at the adductor pollicis muscle using acceleromyography. Arterial plasma rocuronium concentrations. Arterial plasma rocuronium concentrations at 60, 90 and 120 s in the rehydration and control groups were 9.9 and 13.7, 6.8 and 9.5 and 6.2 and 8.1 μg ml, respectively (P = 0.02, 0.003 and 0.02, respectively); the onset times in the rehydration and control groups were 92.0 and 69.5 s (P = 0.01), and the times to twitch re-appearance were 25.3 and 30.4 min (P = 0.004), respectively. Preoperative rehydration significantly reduces arterial plasma rocuronium concentrations in the first 2 minutes after administration, prolonging the onset time and shortening the duration of effect. A higher dose or earlier administration should be considered for patients who receive preoperative rehydration. Umin identifier: UMIN000011981.

Associations between neuromuscular function and levels of physical activity differ for boys and girls during puberty.

Science.gov (United States)

Rudroff, Thorsten; Kelsey, Megan M; Melanson, Edward L; McQueen, Matthew B; Enoka, Roger M

2013-08-01

To compare the associations between neuromuscular performance and anthropometric characteristics with habitual levels of physical activity in boys and girls during the initial stages of puberty. In a cross-sectional study of 72 healthy children (39 boys and 33 girls) ranging in age from 8 to 14 years, sex differences in anthropometric and motor performance characteristics were compared at 3 Tanner stages (T1-T3). Outcome variables included dual-energy x-ray absorptiometry measurements of body composition, assessments of neuromuscular function, and levels of physical activity (steps/day) measured by accelerometry. Physical activity was lower in girls than boys at T2 and T3, but there was no sex difference at T1. Physical activity increased with Tanner stage for boys but did not differ between Tanner stages in girls. Physical activity at each Tanner stage was strongly associated (R(2) > 0.85) with neuromuscular characteristics for both boys and girls, but percentage of body fat also was associated with physical activity for T3 girls. The attenuated gains in neuromuscular function experienced by girls in early stages of puberty were strongly associated with lower levels of physical activity, whereas the increase in physical activity exhibited by boys was mostly related to increases in the strength and endurance of leg muscles. Because sedentary activity is a known contributor to the development of obesity and type 2 diabetes in youth, this study helps to identify possible contributors to decreases in physical activity in young girls and provides potential targets for early intervention. Copyright © 2013 Mosby, Inc. All rights reserved.

Partial neuromuscular blockade in humans enhances muscle blood flow during exercise independently of muscle oxygen uptake and acetylcholine receptor blockade

DEFF Research Database (Denmark)

Hellsten, Ylva; Krustrup, Peter; Iaia, F Marcello

2009-01-01

This study examined the role of acetylcholine for skeletal muscle blood flow during exercise by use of the competitive neuromuscular blocking agent cisatracurium in combination with the acetylcholine receptor blocker glycopyrrone. Nine healthy male subjects performed a 10-min bout of one-legged k......This study examined the role of acetylcholine for skeletal muscle blood flow during exercise by use of the competitive neuromuscular blocking agent cisatracurium in combination with the acetylcholine receptor blocker glycopyrrone. Nine healthy male subjects performed a 10-min bout of one...... conductance during exercise, events that are not associated with either acetylcholine or an increased oxygen demand. The results do not support an essential role for acetylcholine, released form the neuromuscular junction, in exercise hyperaemia or for the enhanced blood flow during neuromuscular blockade....... The enhanced exercise hyperemia during partial neuromuscular blockade may be related to a greater recruitment of fast-twitch muscle fibres. Key words: blood flow, neuromuscular blockade, exercise, skeletal muscle....

Influência da freqüência de estímulos na instalação do bloqueio neuromuscular produzido pelo rocurônio e pancurônio: avaliação pelo método acelerográfico Influencia de la frecuencia de estímulos en la instalación del bloqueo neuromuscular producido por el rocuronio y pancuronio: evaluación por el método acelerográfico Influence of stimulation frequency on rocuronium and pancuronium-induced neuromuscular block onset: acceleromyography evaluation

Directory of Open Access Journals (Sweden)

Derli da Conceição Munhóz

2004-02-01

condiciones de intubación traqueal. RESULTADOS: Los tiempos medios (segundos para el inicio de acción e instalación de bloqueo neuromuscular total producido por el pancuronio fueron: Grupo I (159,33 ± 35,22 y 222 ± 46,56 y Grupo II (77,83 ± 9,52 y 105,96 ± 15,58; para el rocuronio: Grupo I (83 ± 17,25 y 125,33 ± 20,12 y Grupo II (48,96 ± 10,16 y 59,83 ± 10,36 con diferencia significativa entre los grupos. Las condiciones de intubación traqueal fueron satisfactorias en 117 pacientes (97,5% e insatisfactorias en 3 (2,5%. CONCLUSIONES: El inicio de acción y el tiempo para la obtención del bloqueo neuromuscular total en el músculo aductor del pulgar, producidos por el rocuronio y por el pancuronio, son más cortos cuando hay empleo de mayores frecuencias de estímulos.BACKGROUND AND OBJECTIVES: Factors associated to patients and neuromuscular blockers (NMB, as well as others inherent to neuromuscular function monitoring, may affect neuromuscular block onset. This study aimed at the influence of two different stimulation frequencies on rocuronium and pancuronium-induced neuromuscular block. METHODS: Participated in this study 120 patients, physical status ASA I and II, submitted to elective procedures under general anesthesia, who were randomly allocated in two groups, according to the stimulation frequency employed to monitor neuromuscular block: Group I - 0.1 Hz (n = 60 and Group II - 1 Hz (n = 60. Two subgroups were formed within each group (n = 30, according to the neuromuscular blocker: Subgroup P (pancuronium and Subgroup R (rocuronium. Patients were premedicated with muscular midazolam (0.1 mg.kg-1, 30 minutes before surgery. Anesthesia was induced with propofol (2.5 mg.kg-1 preceded by alfentanil (50 µg.kg-1 and followed by pancuronium or rocuronium. Patients were ventilated under mask with 100% oxygen until 75% or more decrease in adductor pollicis muscle response, when laryngoscopy and tracheal intubation were performed. Neuromuscular function was

Selective activation of neuromuscular compartments within the human trapezius muscle

DEFF Research Database (Denmark)

Holtermann, A; Roeleveld, K; Mork, P J

2009-01-01

of the human trapezius muscle can be independently activated by voluntary command, indicating neuromuscular compartmentalization of the trapezius muscle. The independent activation of the upper and lower subdivisions of the trapezius is in accordance with the selective innervation by the fine cranial and main...... branch of the accessory nerve to the upper and lower subdivisions. These findings provide new insight into motor control characteristics, learning possibilities, and function of the clinically relevant human trapezius muscle....

Neuromuscular dose-response studies: determining sample size.

Science.gov (United States)

Kopman, A F; Lien, C A; Naguib, M

2011-02-01

Investigators planning dose-response studies of neuromuscular blockers have rarely used a priori power analysis to determine the minimal sample size their protocols require. Institutional Review Boards and peer-reviewed journals now generally ask for this information. This study outlines a proposed method for meeting these requirements. The slopes of the dose-response relationships of eight neuromuscular blocking agents were determined using regression analysis. These values were substituted for γ in the Hill equation. When this is done, the coefficient of variation (COV) around the mean value of the ED₅₀ for each drug is easily calculated. Using these values, we performed an a priori one-sample two-tailed t-test of the means to determine the required sample size when the allowable error in the ED₅₀ was varied from ±10-20%. The COV averaged 22% (range 15-27%). We used a COV value of 25% in determining the sample size. If the allowable error in finding the mean ED₅₀ is ±15%, a sample size of 24 is needed to achieve a power of 80%. Increasing 'accuracy' beyond this point requires increasing greater sample sizes (e.g. an 'n' of 37 for a ±12% error). On the basis of the results of this retrospective analysis, a total sample size of not less than 24 subjects should be adequate for determining a neuromuscular blocking drug's clinical potency with a reasonable degree of assurance.

Sugammadex for reversal of neuromuscular block after rapid sequence intubation: a systematic review and economic assessment†

Science.gov (United States)

Chambers, D.; Paulden, M.; Paton, F.; Heirs, M.; Duffy, S.; Hunter, J. M.; Sculpher, M.; Woolacott, N.

2010-01-01

Summary Sugammadex 16 mg kg−1 can be used for the immediate reversal of neuromuscular block 3 min after administration of rocuronium and could be used in place of succinylcholine for emergency intubation. We have systematically reviewed the efficacy and cost-effectiveness and made an economic assessment of sugammadex for immediate reversal. The economic assessment investigated whether sugammadex appears cost-effective under various assumptions about the value of any reduction in recovery time with sugammadex, the likelihood of a ‘can't intubate, can't ventilate’ (CICV) event, the age of the patient, and the length of the procedure. Three trials were included in the efficacy review. Sugammadex administered 3 or 5 min after rocuronium produced markedly faster recovery than placebo or spontaneous recovery from succinylcholine-induced block. No published economic evaluations were found. Our economic analyses showed that sugammadex appears more cost-effective, where the value of any reduction in recovery time is greater, where the reduction in mortality compared with succinylcholine is greater, and where the patient is younger, for lower probabilities of a CICV event and for long procedures which do not require profound block throughout. Because of the lack of evidence, the value of some parameters remains unknown, which makes it difficult to provide a definitive assessment of the cost-effectiveness of sugammadex in practice. The use of sugammadex in combination with high-dose rocuronium is efficacious. Further research is needed to clarify key parameters in the analysis and to allow a fuller economic assessment. PMID:20937718

Effects of heavy metals on the neuromuscular transmission of the mouse diaphragm

Energy Technology Data Exchange (ETDEWEB)

Fu, W M; Shiau, S Y.L.

1978-04-01

Effects of heavy metals including Mn, Co, Ni, Cd, Zn, Cu, Sr, Ba, and UO/sub 2//sup +/ ions on the neuromuscular transmission of the mouse diaphragm were studied and compared. From the dose-inhibition curves, the concentrations (mM) required to inhibit 50% of the contraction (ID/sub 50/) for Cd, Mn, Co, Ni, Zn and Sr are 0.03, 0.8, 0.75, 0.82, 1.2 and >20 respectively. In addition to the potent neuromuscular blocking action, both Cd and Zn induce a contracture of the mouse diaphram. Among the cations tested, Cu is the most potent in inducing the contracture. Mn does not cause a contracture, while Co and Ni induce a contracture only after a prolonged incubation for 3 hours. The neuromuscular blocking action of most of the cations tested can be completely or partially reversed by either high Ca or cysteine except the irreversible action of Zn and Cu. These findings suggest that most divalent cations block the neuromuscular transmission by binding to the -SH group of the cell membrane and inhibiting Ca influx. On the other hand, both Ba and UO/sub 2/ at low concentration increase but at high concentration inhibit the twitch response. Sine Ba increases the twitch response of the mouse diaphragm stimulated directly in the presence of d-tubocurarine as well as that stimulated indirectly, Ba/sup + +/ acts mainly directly on the muscle. In contrast, UO/sub 2//sup +/ ions at low concentration increases the twitch response possibly by releasing acetylcholine from the nerve endings.

The influence of gender on neuromuscular pre-activity during side-cutting

DEFF Research Database (Denmark)

Bencke, Jesper; Zebis, Mette K

2011-01-01

investigated. This cross-sectional study aimed to examine gender differences in neuromuscular pre-activity during a maneuver that mimics a movement associated with the incidence of ACL injuries. Twenty-four team handball players (12 male and 12 female) with no history of ACL injury were tested for EMG pre...

Early reversal of profound rocuronium-induced neuromuscular blockade by sugammadex in a randomized multicenter study - Efficacy, safety, and pharmacokinetics

NARCIS (Netherlands)

Sparr, Harald J.; Vermeyen, Karel M.; Beaufort, Anton M.; Rietbergen, Henk; Proost, Johannes H.; Saldien, Vera; Velik-Salchner, Corinna; Wierda, J. Mark K. H.

Background: Sugammadex reverses the neuromuscular blocking effects of rocuronium by chemical encapsulation. The efficacy, safety, and pharmacokinetics of sugammadex for reversal of profound rocuronium-induced neuromuscular blockade were evaluated. Methods: Ninety-eight male adult patients were

Blocking p75 (NTR) receptors alters polyinnervationz of neuromuscular synapses during development.

Science.gov (United States)

Garcia, Neus; Tomàs, Marta; Santafe, Manel M; Lanuza, Maria A; Besalduch, Nuria; Tomàs, Josep

2011-09-01

High-resolution immunohistochemistry shows that the receptor protein p75(NTR) is present in the nerve terminal, muscle cell, and glial Schwann cell at the neuromuscular junction (NMJ) of postnatal rats (P4-P6) during the synapse elimination period. Blocking the receptor with the antibody anti-p75-192-IgG (1-5 μg/ml, 1 hr) results in reduced endplate potentials (EPPs) in mono- and polyinnervated synapses ex vivo, but the mean number of functional inputs per NMJ does not change for as long as 3 hr. Incubation with exogenous brain-derived neurotrophic factor (BDNF) for 1 hr (50 nM) resulted in a significant increase in the size of the EPPs in all nerve terminals, and preincubation with anti-p75-192-IgG prevented this potentiation. Long exposure (24 hr) in vivo of the NMJs to the antibody anti-p75-192-IgG (1-2 μg/ml) results in a delay of postnatal synapse elimination and even some regrowth of previously withdrawn axons, but also in some acceleration of the morphologic maturation of the postsynaptic nicotinic acetylcholine receptor (nAChR) clusters. The results indicate that p75(NTR) is involved in both ACh release and axonal retraction during postnatal axonal competition and synapse elimination. Copyright © 2011 Wiley-Liss, Inc.

Doenças neuromusculares Neuromuscular disorders

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Umbertina C. Reed

2002-08-01

Full Text Available Objetivo: apresentar os dados essenciais para o diagnóstico diferencial entre as principais doenças neuromusculares, denominação genérica sob a qual agrupam-se diferentes afecções, decorrentes do acometimento primário da unidade motora (motoneurônio medular, raiz nervosa, nervo periférico, junção mioneural e músculo. Fontes dos dados: os aspectos clínicos fundamentais para estabelecer o diagnóstico diferencial entre as diferentes doenças neuromusculares, bem como entre estas e as causas de hipotonia muscular secundária ao comprometimento do sistema nervoso central ou a doenças sistêmicas não-neurológicas, são enfatizados, com base na experiência clínica vinda do atendimento a crianças com doenças neuromusculares durante os últimos 12 anos, no ambulatório de doenças neuromusculares do Hospital das Clínicas da Faculdade de Medicina, da Universidade de São Paulo. A revisão bibliográfica foi efetuada através do Medline e do periódico Neuromuscular Disorders, publicação oficial da World Muscle Society. Síntese dos dados: nas crianças, a maior parte destas afecções é geneticamente determinada, sendo as mais comuns a distrofia muscular progressiva ligada ao sexo, de Duchenne, a amiotrofia espinal infantil, a distrofia muscular congênita, a distrofia miotônica de Steinert, e as miopatias congênitas, estruturais e não estruturais. Polineuropatias hereditárias, síndrome miastênica congênita e miopatias metabólicas são menos comuns, porém mostram correlação geno-fenotípica cada vez mais precisa. Conclusões: na década passada, inúmeros avanços da genética molecular facilitaram imensamente o diagnóstico e o aconselhamento genético das doenças neuromusculares mais comuns das crianças, inclusive possibilitando diagnóstico fetal e, adicionalmente, vieram permitir melhor caracterização fenotípica e classificação mais objetiva.Objective: to discuss the most important aspects for performing a

Influence of intense neuromuscular blockade on surgical conditions during laparotomy

DEFF Research Database (Denmark)

Madsen, Matias Vested; Donatsky, Anders Meller; Jensen, Bente Rona

2015-01-01

endotracheally intubated, mechanically ventilated, anesthetized with propofol and fentanyl, and randomized into two groups in a cross-over assessor-blinded design. Neuromuscular block was established with rocuronium. Artificial laparotomy for ileus was performed. We investigated the influence of intense...

Acceleromyography and mechanomyography for establishing potency of neuromuscular blocking agents: a randomized-controlled trial

DEFF Research Database (Denmark)

Claudius, C; Viby-Mogensen, J; Skovgaard, Lene Theil

2009-01-01

) for this purpose. The aim of this study was to compare AMG and MMG for establishing dose-response relationship and potency, using rocuronium as an example. METHODS: We included 40 adult patients in this randomized-controlled single-dose response study. Anaesthesia was induced and maintained with propofol...... and opioid. Neuromuscular blockade was induced with rocuronium 100, 150, 200 or 250 microg/kg. Neuromuscular monitoring was performed with AMG (TOF-Watch SX) with pre-load (Hand Adapter) at one arm and MMG (modified TOF-Watch SX) on the other, using 0.1 Hz single twitch stimulation. Dose...

Neuromuscular control and ankle instability.

Science.gov (United States)

Gutierrez, Gregory M; Kaminski, Thomas W; Douex, Al T

2009-04-01

Lateral ankle sprains (LAS) are common injuries in athletics and daily activity. Although most are resolved with conservative treatment, others develop chronic ankle instability (AI)-a condition associated with persistent pain, weakness, and instability-both mechanical (such as ligamentous laxity) and functional (neuromuscular impairment with or without mechanical laxity). The predominant theory in AI is one of articular deafferentation from the injury, affecting closed-loop (feedback/reflexive) neuromuscular control, but recent research has called that theory into question. A considerable amount of attention has been directed toward understanding the underlying causes of this pathology; however, little is known concerning the neuromuscular mechanisms behind the development of AI. The purpose of this review is to summarize the available literature on neuromuscular control in uninjured individuals and individuals with AI. Based on available research and reasonable speculation, it seems that open-loop (feedforward/anticipatory) neuromuscular control may be more important for the maintenance of dynamic joint stability than closed-loop control systems that rely primarily on proprioception. Therefore, incorporating perturbation activities into patient rehabilitation schemes may be of some benefit in enhancing these open-loop control mechanisms. Despite the amount of research conducted in this area, analysis of individuals with AI during dynamic conditions is limited. Future work should aim to evaluate dynamic perturbations in individuals with AI, as well as subjects who have a history of at least one LAS and never experienced recurrent symptoms. These potential findings may help elucidate some compensatory mechanisms, or more appropriate neuromuscular control strategies after an LAS event, thus laying the groundwork for future intervention studies that can attempt to reduce the incidence and severity of acute and chronic lateral ankle injury.

Neuromuscular activity of Bothrops fonsecai snake venom in vertebrate preparations

Science.gov (United States)

Fernandes, Carla T; Giaretta, Vânia MA; Prudêncio, Luiz S; Toledo, Edvana O; da Silva, Igor RF; Collaço, Rita CO; Barbosa, Ana M; Hyslop, Stephen; Rodrigues-Simioni, Léa; Cogo, José C

2014-01-01

The neuromuscular activity of venom from Bothrops fonsecai, a lancehead endemic to southeastern Brazil, was investigated. Chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND) preparations were used for myographic recordings and mouse diaphragm muscle was used for membrane resting potential (RP) and miniature end-plate potential (MEPP) recordings. Creatine kinase release and muscle damage were also assessed. In CBC, venom (40, 80 and 160μg/ml) produced concentration- and time-dependent neuromuscular blockade (50% blockade in 85±9 min and 73±8 min with 80 and 160μg/ml, respectively) and attenuated the contractures to 110μM ACh (78–100% inhibition) and 40mM KCl (45–90% inhibition). The venom-induced decrease in twitch-tension in curarized, directly-stimulated preparations was similar to that in indirectly stimulated preparations. Venom (100 and 200μg/ml) also caused blockade in PND preparations (50% blockade in 94±13 min and 49±8 min with 100 and 200μg/ml, respectively) but did not alter the RP or MEPP amplitude. In CBC, venom caused creatine kinase release and myonecrosis. The venom-induced decrease in twitch-tension and in the contractures to ACh and K+ were abolished by preincubating venom with commercial antivenom. These findings indicate that Bothrops fonsecai venom interferes with neuromuscular transmission essentially through postsynaptic muscle damage that affects responses to ACh and KCl. These actions are effectively prevented by commercial antivenom. PMID:25028603

An anterior cruciate ligament injury does not affect the neuromuscular function of the non-injured leg except for dynamic balance and voluntary quadriceps activation.

Science.gov (United States)

Zult, Tjerk; Gokeler, Alli; van Raay, Jos J A M; Brouwer, Reinoud W; Zijdewind, Inge; Hortobágyi, Tibor

2017-01-01

The function of the anterior cruciate ligament (ACL) patients' non-injured leg is relevant in light of the high incidence of secondary ACL injuries on the contralateral side. However, the non-injured leg's function has only been examined for a selected number of neuromuscular outcomes and often without appropriate control groups. We measured a broad array of neuromuscular functions between legs of ACL patients and compared outcomes to age, sex, and physical activity matched controls. Thirty-two ACL-deficient patients (208 ± 145 days post-injury) and active and less-active controls (N = 20 each) participated in the study. We measured single- and multi-joint neuromuscular function in both legs in each group and expressed the overall neuromuscular function in each leg by calculating a mean z-score across all neuromuscular measures. A group by leg MANOVA and ANOVA were performed to examine group and leg differences for the selected outcomes. After an ACL injury, duration (-4.3 h/week) and level (Tegner activity score of -3.9) of sports activity decreased and was comparable to less-active controls. ACL patients showed bilateral impairments in the star excursion balance test compared to both control groups (P ≤ 0.004) and for central activation ratio compared to active controls (P ≤ 0.002). There were between-leg differences within each group for maximal quadriceps and hamstring strength, voluntary quadriceps activation, star excursion balance test performance, and single-leg hop distance (all P joint proprioception, and static balance. Overall neuromuscular function (mean z-score) did not differ between groups, but ACL patients' non-injured leg displayed better neuromuscular function than the injured leg (P neuromuscular deficits despite reductions in physical activity after injury. Therapists can use the non-injured leg as a reference to assess the injured leg's function for tasks measured in the present study, excluding dynamic balance and quadriceps

Rocuronium and sugammadex in a 3 days old neonate for draining an ovarian cyst. Neuromuscular management and review of the literature

Directory of Open Access Journals (Sweden)

Ricardo Vieira Carlos

2016-08-01

Full Text Available Abstract A case is reported in which a 3-days old neonate with a giant ovarian cyst was scheduled for surgery. The patient received a dose of sugammadex to reverse a rocuronium-induced neuromuscular block. A fast and efficient recovery from neuromuscular block was achieved within 90 s. No adverse events or other safety concerns were observed. Furthermore, a review of the literature on the use of sugammadex in neonates was performed.

Evidence-Based Systematic Review: Effects of Neuromuscular Electrical Stimulation on Swallowing and Neural Activation

Science.gov (United States)

Clark, Heather; Lazarus, Cathy; Arvedson, Joan; Schooling, Tracy; Frymark, Tobi

2009-01-01

Purpose: To systematically review the literature examining the effects of neuromuscular electrical stimulation (NMES) on swallowing and neural activation. The review was conducted as part of a series examining the effects of oral motor exercises (OMEs) on speech, swallowing, and neural activation. Method: A systematic search was conducted to…

Is there any relationship between orthotic usage and functional activities in children with neuromuscular disorders?

Science.gov (United States)

Alemdaroğlu, İpek; Gür, Gozde; Bek, Nilgün; Yilmaz, Öznur T; Yakut, Yavuz; Uygur, Fatma; Karaduman, Ayşe

2014-02-01

Contractures of Achilles tendons and gastrocnemius muscle deteriorate the performance in daily living activities of patients with neuromuscular diseases. Ankle-foot orthoses help to prevent the progression of deformities and to obtain optimal position of the joints to support standing and walking. To investigate the relationship between orthotic usage and functional activities in pediatric patients with different neuromuscular diseases. Retrospective study. A total of 127 subjects' physical assessment forms were analyzed. Functional level, type of orthoses, falling frequencies, ankle joint range of motion, and timed performance tests were examined in two consecutive dates with an interval of 3 months. A total of 91 patients were using orthoses while 36 patients were not within assessment dates. A total of 64 of 91 (70.3%) patients were diagnosed with Duchenne muscular dystrophy. A total of 81 (89.0%) subjects were using plastic ankle-foot orthoses for positioning at nights and 10 (11%) were using different types of the orthoses (knee-ankle-foot orthoses, dynamic ankle-foot orthoses, and so on) for gait in the study group. Night ankle-foot orthoses were not found to be effective directly on functional performance in children with neuromuscular diseases, although they protect ankle from contractures and may help to correct gait and balance. This retrospective study shows that the positive effects of using an ankle-foot orthosis at night are not reflected in the functional performance of children with neuromuscular diseases. This may be due to the progressive deteriorating nature of the disease.

The Influence of Robotic Assistance on Reducing Neuromuscular Effort and Fatigue during Extravehicular Activity Glove Use

Science.gov (United States)

Madden, Kaci E.; Deshpande, Ashish D.; Peters, Benjamin J.; Rogers, Jonathan M.; Laske, Evan A.; McBryan, Emily R.

2017-01-01

The three-layered, pressurized space suit glove worn by Extravehicular Activity (EVA) crew members during missions commonly causes hand and forearm fatigue. The Spacesuit RoboGlove (SSRG), a Phase VI EVA space suit glove modified with robotic grasp-assist capabilities, has been developed to augment grip strength in order to improve endurance and reduce the risk of injury in astronauts. The overall goals of this study were to i) quantify the neuromuscular modulations that occur in response to wearing a conventional Phase VI space suit glove (SSG) during a fatiguing task, and ii) determine the efficacy of Spacesuit RoboGlove (SSRG) in reversing the adverse neuromuscular modulations and restoring altered muscular activity to barehanded levels. Six subjects performed a fatigue sequence consisting of repetitive dynamic-gripping interspersed with isometric grip-holds under three conditions: barehanded, wearing pressurized SSG, and wearing pressurized SSRG. Surface electromyography (sEMG) from six forearm muscles (flexor digitorum superficialis (FDS), flexor carpi radialis (FCR), flexor carpi ulnaris (FCU), extensor digitorum (ED), extensor carpi radialis longus (ECRL), and extensor carpi ulnaris (ECU)) and subjective fatigue ratings were collected during each condition. Trends in amplitude and spectral distributions of the sEMG signals were used to derive metrics quantifying neuromuscular effort and fatigue that were compared across the glove conditions. Results showed that by augmenting finger flexion, the SSRG successfully reduced the neuromuscular effort needed to close the fingers of the space suit glove in more than half of subjects during two types of tasks. However, the SSRG required more neuromuscular effort to extend the fingers compared to a conventional SSG in many subjects. Psychologically, the SSRG aided subjects in feeling less fatigued during short periods of intense work compared to the SSG. The results of this study reveal the promise of the SSRG as a

Interaction of antibiotics on pipecuronium-induced neuromuscular blockade.

Science.gov (United States)

de Gouw, N E; Crul, J F; Vandermeersch, E; Mulier, J P; van Egmond, J; Van Aken, H

1993-01-01

To measure the interaction of two antibiotics (clindamycin and colistin) on neuromuscular blockade induced by pipecuronium bromide (a new long-acting, steroidal, nondepolarizing neuromuscular blocking drug). Prospective, randomized, placebo-controlled study. Inpatient gynecologic and gastroenterologic service at a university medical center. Three groups of 20 ASA physical status I and II patients with normal kidney and liver function, taking no medication, and undergoing elective surgery under general anesthesia. Anesthesia was induced with propofol and alfentanil intravenously (IV) and maintained with a propofol infusion and 60% nitrous oxide in oxygen. Pipecuronium bromide 50 micrograms/kg was administered after reaching a stable baseline of single-twitch response. At 25% recovery of pipecuronium-induced neuromuscular blockade, patients received one of two antibiotics, clindamycin 300 mg or colistin 1 million IU, or a placebo. The recovery index (RI, defined as time from 25% to 75% recovery of neuromuscular blockade) was measured using the single-twitch response of the adductor pollicis muscle with supramaximal stimulation of the ulnar nerve at the wrist. RI after administration of an antibiotic (given at 25% recovery) was measured and compared with RI of the control group using Student's unpaired t-test. Statistical analyses of the results showed a significant prolongation of the recovery time (from 25% to 75% recovery) of 40 minutes for colistin. When this type of antibiotic is used during anesthesia with pipercuronium as a muscle relaxant, one must be aware of a significant prolongation of an already long-acting neuromuscular blockade and (although not observed in this study) possible problems in antagonism.

Impact of high- versus low-dose neuromuscular blocking agent administration on unplanned 30-day readmission rates in retroperitoneal laparoscopic surgery.

Directory of Open Access Journals (Sweden)

Martijn Boon

Full Text Available Recent data shows that a neuromuscular block (NMB induced by administration of high doses of rocuronium improves surgical conditions in certain procedures. However, there are limited data on the effect such practices on postoperative outcomes. We performed a retrospective analysis to compare unplanned 30-day readmissions in patients that received high-dose versus low-dose rocuronium administration during general anesthesia for laparoscopic retroperitoneal surgery. This retrospective cohort study was performed in the Netherlands in an academic hospital where routine high-dose rocuronium NMB has been practiced since July 2015. Charts of patients receiving anesthesia between January 2014 and December 2016 were searched for surgical cases receiving high-dose rocuronium and matched with respect to procedure, age, sex and ASA classification to patients receiving low-dose rocuronium. The primary post-operative outcome was unplanned 30-day readmission rate. There were 130 patients in each cohort. Patients in the high- and low-dose rocuronium cohorts received 217 ± 49 versus 37 ± 5 mg rocuronium, respectively. In the high-dose rocuronium group neuromuscular activity was consistently monitored; matched patients were unreliably monitored. All patients receiving high-dose rocuronium were reversed with sugammadex, while just 33% of matched patients were reversed with sugammadex and 20% with neostigmine; the remaining patients were not reversed. Unplanned 30-day readmission rate was significantly lower in the high-dose compared to the low-dose rocuronium cohort (3.8% vs. 12.7%; p = 0.03; odds ratio = 0.33, 95% C.I. 0.12-0.95. This small retrospective study demonstrates a lower incidence of unplanned readmissions within 30-days following laparoscopic retroperitoneal surgery with high-dose relaxant anesthesia and sugammadex reversal in comparison to low-dose relaxant anesthesia. Further prospective studies are needed in larger samples to corroborate our

Impact of high- versus low-dose neuromuscular blocking agent administration on unplanned 30-day readmission rates in retroperitoneal laparoscopic surgery.

Science.gov (United States)

Boon, Martijn; Martini, Chris; Yang, H Keri; Sen, Shuvayu S; Bevers, Rob; Warlé, Michiel; Aarts, Leon; Niesters, Marieke; Dahan, Albert

2018-01-01

Recent data shows that a neuromuscular block (NMB) induced by administration of high doses of rocuronium improves surgical conditions in certain procedures. However, there are limited data on the effect such practices on postoperative outcomes. We performed a retrospective analysis to compare unplanned 30-day readmissions in patients that received high-dose versus low-dose rocuronium administration during general anesthesia for laparoscopic retroperitoneal surgery. This retrospective cohort study was performed in the Netherlands in an academic hospital where routine high-dose rocuronium NMB has been practiced since July 2015. Charts of patients receiving anesthesia between January 2014 and December 2016 were searched for surgical cases receiving high-dose rocuronium and matched with respect to procedure, age, sex and ASA classification to patients receiving low-dose rocuronium. The primary post-operative outcome was unplanned 30-day readmission rate. There were 130 patients in each cohort. Patients in the high- and low-dose rocuronium cohorts received 217 ± 49 versus 37 ± 5 mg rocuronium, respectively. In the high-dose rocuronium group neuromuscular activity was consistently monitored; matched patients were unreliably monitored. All patients receiving high-dose rocuronium were reversed with sugammadex, while just 33% of matched patients were reversed with sugammadex and 20% with neostigmine; the remaining patients were not reversed. Unplanned 30-day readmission rate was significantly lower in the high-dose compared to the low-dose rocuronium cohort (3.8% vs. 12.7%; p = 0.03; odds ratio = 0.33, 95% C.I. 0.12-0.95). This small retrospective study demonstrates a lower incidence of unplanned readmissions within 30-days following laparoscopic retroperitoneal surgery with high-dose relaxant anesthesia and sugammadex reversal in comparison to low-dose relaxant anesthesia. Further prospective studies are needed in larger samples to corroborate our findings and

Knee and Hip Joint Kinematics Predict Quadriceps and Hamstrings Neuromuscular Activation Patterns in Drop Jump Landings.

Directory of Open Access Journals (Sweden)

Bart Malfait

Full Text Available The purpose was to assess if variation in sagittal plane landing kinematics is associated with variation in neuromuscular activation patterns of the quadriceps-hamstrings muscle groups during drop vertical jumps (DVJ.Fifty female athletes performed three DVJ. The relationship between peak knee and hip flexion angles and the amplitude of four EMG vectors was investigated with trajectory-level canonical correlation analyses over the entire time period of the landing phase. EMG vectors consisted of the {vastus medialis(VM,vastus lateralis(VL}, {vastus medialis(VM,hamstring medialis(HM}, {hamstring medialis(HM,hamstring lateralis(HL} and the {vastus lateralis(VL,hamstring lateralis(HL}. To estimate the contribution of each individual muscle, linear regressions were also conducted using one-dimensional statistical parametric mapping.The peak knee flexion angle was significantly positively associated with the amplitudes of the {VM,HM} and {HM,HL} during the preparatory and initial contact phase and with the {VL,HL} vector during the peak loading phase (p<0.05. Small peak knee flexion angles were significantly associated with higher HM amplitudes during the preparatory and initial contact phase (p<0.001. The amplitudes of the {VM,VL} and {VL,HL} were significantly positively associated with the peak hip flexion angle during the peak loading phase (p<0.05. Small peak hip flexion angles were significantly associated with higher VL amplitudes during the peak loading phase (p = 0.001. Higher external knee abduction and flexion moments were found in participants landing with less flexed knee and hip joints (p<0.001.This study demonstrated clear associations between neuromuscular activation patterns and landing kinematics in the sagittal plane during specific parts of the landing. These findings have indicated that an erect landing pattern, characterized by less hip and knee flexion, was significantly associated with an increased medial and posterior

Neuroleptics as therapeutic compounds stabilizing neuromuscular transmission in amyotrophic lateral sclerosis.

Science.gov (United States)

Patten, Shunmoogum A; Aggad, Dina; Martinez, Jose; Tremblay, Elsa; Petrillo, Janet; Armstrong, Gary Ab; La Fontaine, Alexandre; Maios, Claudia; Liao, Meijiang; Ciura, Sorana; Wen, Xiao-Yan; Rafuse, Victor; Ichida, Justin; Zinman, Lorne; Julien, Jean-Pierre; Kabashi, Edor; Robitaille, Richard; Korngut, Lawrence; Parker, J Alexander; Drapeau, Pierre

2017-11-16

Amyotrophic lateral sclerosis (ALS) is a rapidly progressing, fatal disorder with no effective treatment. We used simple genetic models of ALS to screen phenotypically for potential therapeutic compounds. We screened libraries of compounds in C. elegans, validated hits in zebrafish, and tested the most potent molecule in mice and in a small clinical trial. We identified a class of neuroleptics that restored motility in C. elegans and in zebrafish, and the most potent was pimozide, which blocked T-type Ca2+ channels in these simple models and stabilized neuromuscular transmission in zebrafish and enhanced it in mice. Finally, a short randomized controlled trial of sporadic ALS subjects demonstrated stabilization of motility and evidence of target engagement at the neuromuscular junction. Simple genetic models are, thus, useful in identifying promising compounds for the treatment of ALS, such as neuroleptics, which may stabilize neuromuscular transmission and prolong survival in this disease.

Influence of patterned electrical neuromuscular stimulation on quadriceps activation in individuals with knee joint injury.

Science.gov (United States)

Glaviano, Neal R; Langston, William T; Hart, Joseph M; Saliba, Susan

2014-12-01

Neuromuscular Electrical Stimulation is a common intervention to address muscle weakness, however presents with many limitations such as fatigue, muscle damage, and patient discomfort that may influence its effectiveness. One novel form of electrical stimulation purported to improve neuromuscular re-education is Patterned Electrical Neuromuscular Stimulation (PENS), which is proposed to mimic muscle-firing patterns of healthy individuals. PENS provides patterned stimulating to the agonist muscle, antagonist muscle and then agonist muscle again in an effort to replicate firing patterns. The purpose of this study was to determine the effect of a single PENS treatment on knee extension torque and quadriceps activation in individuals with quadriceps inhibition. 18 subjects (10 males and 8 females: 24.2±3.4 years, 175.3±11.8cm, 81.8±12.4kg) with a history of knee injury/pain participated in this double-blinded randomized controlled laboratory trial. Participants demonstrated quadriceps inhibition with a central activation ratio of ≤90%. Maximal voluntary isometric contraction of the quadriceps and central activation ratio were measured before and after treatment. The treatment intervention was a 15-minute patterned electrical stimulation applied to the quadriceps and hamstring muscles with a strong motor contraction or a sham group, who received an identical set up as the PENS group, but received a 1mA subsensory stimulation. A 2×2 (group × time) ANCOVA was used to determine differences in maximal voluntary isometric contraction and central activation ratio between groups. The maximal voluntary isometric contraction was selected as a covariate due to baseline differences. There were no differences in change scores between pre- and post-intervention for maximal voluntary isometric contraction: (PENS: 0.09±0.32Nm/kg and Sham 0.15±0.18Nm/kg, p=0.713), or central activation ratio:(PENS: -1.22±6.06 and Sham: 1.48±3.7, p=0.270). A single Patterned Electrical

Improving Neuromuscular Monitoring and Reducing Residual Neuromuscular Blockade With E-Learning: Protocol for the Multicenter Interrupted Time Series INVERT Study.

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Thomsen, Jakob Louis Demant; Mathiesen, Ole; Hägi-Pedersen, Daniel; Skovgaard, Lene Theil; Østergaard, Doris; Engbaek, Jens; Gätke, Mona Ring

2017-10-06

Muscle relaxants facilitate endotracheal intubation under general anesthesia and improve surgical conditions. Residual neuromuscular blockade occurs when the patient is still partially paralyzed when awakened after surgery. The condition is associated with subjective discomfort and an increased risk of respiratory complications. Use of an objective neuromuscular monitoring device may prevent residual block. Despite this, many anesthetists refrain from using the device. Efforts to increase the use of objective monitoring are time consuming and require the presence of expert personnel. A neuromuscular monitoring e-learning module might support consistent use of neuromuscular monitoring devices. The aim of the study is to assess the effect of a neuromuscular monitoring e-learning module on anesthesia staff's use of objective neuromuscular monitoring and the incidence of residual neuromuscular blockade in surgical patients at 6 Danish teaching hospitals. In this interrupted time series study, we are collecting data repeatedly, in consecutive 3-week periods, before and after the intervention, and we will analyze the effect using segmented regression analysis. Anesthesia departments in the Zealand Region of Denmark are included, and data from all patients receiving a muscle relaxant are collected from the anesthesia information management system MetaVision. We will assess the effect of the module on all levels of potential effect: staff's knowledge and skills, patient care practice, and patient outcomes. The primary outcome is use of neuromuscular monitoring in patients according to the type of muscle relaxant received. Secondary outcomes include last recorded train-of-four value, administration of reversal agents, and time to discharge from the postanesthesia care unit as well as a multiple-choice test to assess knowledge. The e-learning module was developed based on a needs assessment process, including focus group interviews, surveys, and expert opinions. The e

Dynamic Neuromuscular Control of the Lower Limbs in Response to Unexpected Single-Planar versus Multi-Planar Support Perturbations in Young, Active Adults.

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Malfait, Bart; Staes, Filip; de Vries, Aijse; Smeets, Annemie; Hawken, Malcolm; Robinson, Mark A; Vanrenterghem, Jos; Verschueren, Sabine

2015-01-01

An anterior cruciate ligament (ACL) injury involves a multi-planar injury mechanism. Nevertheless, unexpected multi-planar perturbations have not been used to screen athletes in the context of ACL injury prevention yet could reveal those more at risk. The objective of this study was to compare neuromuscular responses to multi-planar (MPP) and single-planar perturbations (SPP) during a stepping-down task. These results might serve as a basis for future implementation of external perturbations in ACL injury screening programs. Thirteen young adults performed a single leg stepping-down task in eight conditions (four MPP and four SPP with a specified amplitude and velocity). The amplitudes of vastus lateralis (VL), vastus medialis (VM), hamstrings lateralis (HL), hamstrings medialis (HM) EMG activity, medio-lateral and anterior-posterior centre of mass (COM) displacements, the peak knee flexion and abduction angles were compared between conditions using an one-way ANOVA. Number of stepping responses were monitored during all conditions. Significantly greater muscle activity levels were found in response to the more challenging MPP and SPP compared to the less challenging conditions (p neuromuscular activity were found between the MPP conditions and their equivalents in the SPP. Eighteen stepping responses were monitored in the SPP versus nine in the MPP indicating that the overall neuromuscular control was even more challenged during the SPP which was supported by greater COM displacements in the SPP. The more intense MPP and SPP evoked different neuromuscular responses resulting in greater muscle activity levels compared to small perturbations. Based on the results of COM displacements and based on the amount of stepping responses, dynamic neuromuscular control of the knee joint appeared less challenged during the MPP. Therefore, future work should investigate extensively if other neuromuscular differences (i.e. co-activation patterns and kinetics) exist between MPP

Phenobarbital influence on neuromuscular block produced by rocuronium in rats Influência do fenobarbital no bloqueio neuromuscular produzido pelo rocurônio em ratos

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Angélica de Fátima de Assunção Braga

2008-08-01

Full Text Available PURPOSE: To evaluate in vitro and in vivo neuromuscular blockade produced by rocuronium in rats treated with Phenobarbital and to determine cytochrome P450 and cytochrome b5 concentrations in hepatic microsomes. METHODS: Thirty rats were included in the study and distributed into 6 groups of 5 animals each. Rats were treated for seven days with phenobarbital (20 mg/kg and the following parameters were evaluated: 1 the amplitude of muscle response in the preparation of rats exposed to phenobarbital; 2 rocuronium effect on rat preparation exposed or not to phenobarbital; 3 concentrations of cytochrome P450 and cytochrome b5 in hepatic microsomes isolated from rats exposed or not to phenobarbital. The concentration and dose of rocuronium used in vitro and in vivo experiments were 4 µg/mL and 0,6 mg/kg, respectively. RESULTS: Phenobarbital in vitro and in vivo did not alter the amplitude of muscle response. The neuromuscular blockade in vitro produced by rocuronium was significantly different (p=0.019 between exposed (20% and not exposed (60% rats; the blockade in vivo was significantly greater (p=0.0081 in treated rats (93.4%. The enzymatic concentrations were significantly greater in rats exposed to phenobarbital. CONCLUSIONS: Phenobarbital alone did not compromise neuromuscular transmission. It produced enzymatic induction, and neuromuscular blockade in vivo produced by rocuronium was potentiated by phenobarbital.OBJETIVO: Avaliar in vitro e in vivo o bloqueio neuromuscular produzido pelo rocurônio em ratos tratados com fenobarbital e determinar as concentrações de citocromo P450 e b5 em microssomos hepáticos. MÉTODOS: Trinta ratos foram incluídos no estudo e distribuídos em seis grupos de cinco animais cada. Ratos foram tratados por sete dias com fenobarbital (20 mg/kg e avaliou-se: 1 amplitude das respostas musculares em preparação de ratos expostos ao fenobarbital; 2 o efeito do rocurônio em preparações de ratos expostos ou n

Ammonia modifies enteric neuromuscular transmission through glial γ-aminobutyric acid signaling.

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Fried, David E; Watson, Ralph E; Robson, Simon C; Gulbransen, Brian D

2017-12-01

Impaired gut motility may contribute, at least in part, to the development of systemic hyperammonemia and systemic neurological disorders in inherited metabolic disorders, or in severe liver and renal disease. It is not known whether enteric neurotransmission regulates intestinal luminal and hence systemic ammonia levels by induced changes in motility. Here, we propose and test the hypothesis that ammonia acts through specific enteric circuits to influence gut motility. We tested our hypothesis by recording the effects of ammonia on neuromuscular transmission in tissue samples from mice, pigs, and humans and investigated specific mechanisms using novel mutant mice, selective drugs, cellular imaging, and enzyme-linked immunosorbent assays. Exogenous ammonia increased neurogenic contractions and decreased neurogenic relaxations in segments of mouse, pig, and human intestine. Enteric glial cells responded to ammonia with intracellular Ca 2+ responses. Inhibition of glutamine synthetase and the deletion of glial connexin-43 channels in hGFAP :: Cre ER T2+/- /connexin43 f/f mice potentiated the effects of ammonia on neuromuscular transmission. The effects of ammonia on neuromuscular transmission were blocked by GABA A receptor antagonists, and ammonia drove substantive GABA release as did the selective pharmacological activation of enteric glia in GFAP::hM3Dq transgenic mice. We propose a novel mechanism whereby local ammonia is operational through GABAergic glial signaling to influence enteric neuromuscular circuits that regulate intestinal motility. Therapeutic manipulation of these mechanisms may benefit a number of neurological, hepatic, and renal disorders manifesting hyperammonemia. NEW & NOTEWORTHY We propose that local circuits in the enteric nervous system sense and regulate intestinal ammonia. We show that ammonia modifies enteric neuromuscular transmission to increase motility in human, pig, and mouse intestine model systems. The mechanisms underlying the

Effects of exercise on activity-and blood flow-related neuromuscular degeneration

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Ishihara, Akihiko; 石原　昭彦

2006-01-01

Effects of running exercise with increasing loads on hindlimb unloading-induced neuromuscular degeneration in male rats were investigated. Ten-week-old male rats were hindlimb suspended at horizontal position for two weeks and thereafter were rehabilitated by voluntary running exercise with increasing loads for two weeks. A decreased percentage of type 1 fibers and atrophy and decreased oxidative enzyme activity of all types of fibers in the soleus muscle were observed after hindlimb unloadin...

Neuromuscular function during a forward lunge in meniscectomized patients

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Thorlund, Jonas Bloch; Damgaard, Jacob; Roos, Ewa M.

2012-01-01

This study aimed to investigate differences in knee joint kinematics, ground reaction force kinetics and neuromuscular activity including muscle coactivation, and medial versus lateral muscle activity during a forward lunge between the operated and contralateral legs of meniscectomized patients....... Such differences may represent early changes in neuromuscular function potentially contributing to the development of knee osteoarthritis....

INTERACTION OF VERAPAMIL AND LITHIUM AT THE NEUROMUSCULAR JUNCTION ON RAT ISOLATED MUSCLE-HEMIDIAPHRAGM

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H. R. Sadeghipour

1998-08-01

Full Text Available It has been reported that cither lithium or verapamil can potentiate the neuromuscular blocking activity of certain neuromuscular blockers. In the present investigation, possible interaction of verapamil with lithium has been described. The dose ■ response effects of verapamil and lithium on diaphragmatic contractility were assessed in vitro. Mechanical responses of the muscle to indirect (nerve and direct (muscle electrical stimulation were recorded. Verapamil depressed rat diaphragm twitch tensions induced by nerve stimulation in a dose - dependent manner with the 50 percent depression of the original twitch tensions (ICSQ by 5.6 xlO^mmol/l."nThe IC50 of verapamil for direct stimulation of the muscle was LI x W'5 mmol II. Partial replacement of sodium chloride by lithium chloride (0.5, 1.5 and 5 mmol /1 in the medium did not change the depressant effect of verapamil on muscle twitches induced by direct (muscle or indirect (nerve electrical stimulation.

Profile of sugammadex for reversal of neuromuscular blockade in the elderly: current perspectives.

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Carron, Michele; Bertoncello, Francesco; Ieppariello, Giovanna

2018-01-01

The number of elderly patients is increasing worldwide. This will have a significant impact on the practice of anesthesia in future decades. Anesthesiologists must provide care for an increasing number of elderly patients, who have an elevated risk of perioperative morbidity and mortality. Complications related to postoperative residual neuromuscular blockade, such as muscle weakness, airway obstruction, hypoxemia, atelectasis, pneumonia, and acute respiratory failure, are more frequent in older than in younger patients. Therefore, neuromuscular blockade in the elderly should be carefully monitored and completely reversed before awakening patients at the end of anesthesia. Acetylcholinesterase inhibitors are traditionally used for reversal of neuromuscular blockade. Although the risk of residual neuromuscular blockade is reduced by reversal with neostigmine, it continues to complicate the postoperative course. Sugammadex represents an innovative approach to reversal of neuromuscular blockade induced by aminosteroid neuromuscular-blocking agents, particularly rocuronium, with useful applications in clinical practice. However, aging is associated with certain changes in the pharmacokinetics of sugammadex, and to date there has been no thorough evaluation of the use of sugammadex in elderly patients. The aim of this review was to perform an analysis of the use of sugammadex in older adults based on the current literature. Major issues surrounding the physiologic and pharmacologic effects of aging in elderly patients and how these may impact the routine use of sugammadex in elderly patients are discussed.

Neuromuscular Activity and Knee Kinematics in Adolescents with Patellofemoral Pain

DEFF Research Database (Denmark)

Rathleff, Michael Skovdal; Samani, Afshin; Olesen, Jens L

2013-01-01

This study aimed to investigate the neuromuscular control of the knee during stair descent among female adolescents with patellofemoral pain (PFP) and to report its association with self-reported clinical status assessed by the Knee Injury and Osteoarthritis Outcome Score (KOOS).......This study aimed to investigate the neuromuscular control of the knee during stair descent among female adolescents with patellofemoral pain (PFP) and to report its association with self-reported clinical status assessed by the Knee Injury and Osteoarthritis Outcome Score (KOOS)....

Characterization of cervical neuromuscular response to head-neck perturbation in active young adults.

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Alsalaheen, Bara; Bean, Ryan; Almeida, Andrea; Eckner, James; Lorincz, Matthew

2018-04-01

The majority of studies examining the role of cervical muscles on head-neck kinematics focused on musculoskeletal attributes (e.g. strength). Cervical neuromuscular response to perturbation may represent a divergent construct that has not been examined under various perturbation conditions. This study examined the association between cervical musculoskeletal attributes and cervical neuromuscular response of the sternocleidomastoid (SCM) to perturbation. Furthermore, this study examined the effect of anticipation and preload on the SCM neuromuscular response. Nineteen participants completed measurement of SCM muscle size, cervical flexion maximal voluntary isometric contraction, and the neuromuscular response of the SCM to cervical perturbation. Cervical perturbation was delivered by dropping a 1.59 kg mass from a loading apparatus. The impulsive load was delivered under four conditions: (1) Anticipated perturbation with no preload (A-NP), (2) Unanticipated perturbation with no preload (U-NP), (3) Anticipated perturbation with preload (A-P), and (4) Unanticipated perturbation with preload (U-P). None of the cervical musculoskeletal attributes were correlated with the SCM cervical neuromuscular response. This study demonstrated significant effect of preloading and anticipation on baseline EMG amplitude and EMG onset latency for the SCM. Furthermore, there was a significant effect of preloading on average EMG response amplitude for the SCM. The findings of this study indicate that cervical neuromuscular response of the SCM is different from musculoskeletal attributes and is influenced by perturbation conditions. These findings provide conceptual support to examine the neuromuscular response of the SCM in mitigating head-neck kinematics. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ensayos en Ambiente Hospitalario de Técnicas de Monitorización de Bloqueo Neuromuscular: Resultados Preliminares

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Yadel Forneiro Martín Viaña

2014-07-01

Introduction: In order to evaluate the magnitude of neuromuscular blocking during anesthesia, the anesthesiologists consider the muscular response to peripheral nerves stimulation. Objective: Study aims to calculate muscle relaxation indicators, through neuromuscular blocking and its algorithms using a Cuban made monitoring device during the medical procedure. Materials and methods: Thumb kinetic response and muscles relaxation indicators were registered and calculated automatically; for this purpose, median and nerves trials using Troin-of – Four (TOF were conducted in shorter surgeries, which allowed to monitor patients’ neuromuscular, intraoperative function. Scientific consel and the Committee of Ethics of the Clinical Surgical Hospital “HermanosAmeijeiras” approved the protocol, based on a research project conducted by the ICID – Medical Digital technology and the Hospital. Results: the monitoring was stable during all medical procedures as indicated on graph data obtained during five sample cases indicating muscle relaxation indicators. Conclusion: muscle relaxation indicators registered during trials showed significant relevance relation to patient’s clinical history, giving support to evidence of the monitoring implemented techniques based on specialists’ criteria.

Reversal of rocuronium-induced (1.2 mg/kg) profound neuromuscular block by sugammadex: a multicenter, dose-finding and safety study.

NARCIS (Netherlands)

Boer, H.D. de; Driessen, J.J.; Marcus, M.A.; Kerkkamp, H.E.M.; Heeringa, M.; Klimek, M.

2007-01-01

BACKGROUND: Reversal of rocuronium-induced neuromuscular blockade can be accomplished by chemical encapsulation of rocuronium by sugammadex, a modified gamma-cyclodextrin derivative. This study investigated the efficacy and safety of sugammadex in reversing rocuronium-induced profound neuromuscular

Profile of sugammadex for reversal of neuromuscular blockade in the elderly: current perspectives

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Carron M

2017-12-01

Full Text Available Michele Carron, Francesco Bertoncello, Giovanna Ieppariello Department of Medicine, Anesthesiology, and Intensive Care, University of Padova, Padua, Italy Abstract: The number of elderly patients is increasing worldwide. This will have a significant impact on the practice of anesthesia in future decades. Anesthesiologists must provide care for an increasing number of elderly patients, who have an elevated risk of perioperative morbidity and mortality. Complications related to postoperative residual neuromuscular blockade, such as muscle weakness, airway obstruction, hypoxemia, atelectasis, pneumonia, and acute respiratory failure, are more frequent in older than in younger patients. Therefore, neuromuscular blockade in the elderly should be carefully monitored and completely reversed before awakening patients at the end of anesthesia. Acetylcholinesterase inhibitors are traditionally used for reversal of neuromuscular blockade. Although the risk of residual neuromuscular blockade is reduced by reversal with neostigmine, it continues to complicate the postoperative course. Sugammadex represents an innovative approach to reversal of neuromuscular blockade induced by aminosteroid neuromuscular-blocking agents, particularly rocuronium, with useful applications in clinical practice. However, aging is associated with certain changes in the pharmacokinetics of sugammadex, and to date there has been no thorough evaluation of the use of sugammadex in elderly patients. The aim of this review was to perform an analysis of the use of sugammadex in older adults based on the current literature. Major issues surrounding the physiologic and pharmacologic effects of aging in elderly patients and how these may impact the routine use of sugammadex in elderly patients are discussed. Keywords: sugammadex, aging, elderly, neuromuscular blockade, rocuronium, anesthesia, safety

Do changes in neuromuscular activation contribute to the knee extensor angle-torque relationship?

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Lanza, Marcel B; Balshaw, Thomas G; Folland, Jonathan P

2017-08-01

What is the central question of the study? Do changes in neuromuscular activation contribute to the knee extensor angle-torque relationship? What is the main finding and its importance? Both agonist (quadriceps) and antagonist coactivation (hamstrings) differed with knee joint angle during maximal isometric knee extensions and thus both are likely to contribute to the angle-torque relationship. Specifically, two independent measurement techniques showed quadriceps activation to be lower at more extended positions. These effects might influence the capacity for neural changes in response to training and rehabilitation at different knee joint angles. The influence of joint angle on knee extensor neuromuscular activation is unclear, owing in part to the diversity of surface electromyography (sEMG) and/or interpolated twitch technique (ITT) methods used. The aim of the study was to compare neuromuscular activation, using rigorous contemporary sEMG and ITT procedures, during isometric maximal voluntary contractions (iMVCs) of the quadriceps femoris at different knee joint angles and examine whether activation contributes to the angle-torque relationship. Sixteen healthy active men completed two familiarization sessions and two experimental sessions of isometric knee extension and knee flexion contractions. The experimental sessions included the following at each of four joint angles (25, 50, 80 and 106 deg): iMVCs (with and without superimposed evoked doublets); submaximal contractions with superimposed doublets; and evoked twitch and doublet contractions whilst voluntarily passive, and knee flexion iMVC at the same knee joint positions. The absolute quadriceps femoris EMG was normalized to the peak-to-peak amplitude of an evoked maximal M-wave, and the doublet-voluntary torque relationship was used to calculate activation with the ITT. Agonist activation, assessed with both normalized EMG and the ITT, was reduced at the more extended compared with the more flexed

Knee joint kinaesthesia and neuromuscular coordination during three phases of the menstrual cycle in moderately active women.

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Fridén, Cecilia; Hirschberg, Angelica Lindén; Saartok, Tönu; Renström, Per

2006-04-01

An increased incidence of sports related injuries in the premenstrual phase as well as in the menstrual phase of the menstrual cycle has been described. This may be explained by alterations in proprioception and neuromuscular coordination due to hormonal variations. Prospective, within women analysis of knee joint kinesthesia and neuromuscular coordination were performed by repeated measures analysis of variance in three hormonally verified phases of three consecutive menstrual cycles. Thirty-two healthy, moderately active female subjects volunteered to participate in the study. Twenty-five of the subjects performed at least one hormonally verified menstrual cycle. A specially designed device was used to investigate knee joint kinaesthesia and neuromuscular coordination was measured with the square hop test. These tests were carried out in the menstrual phase, ovulation phase and premenstrual phase determined by hormone analyses in three consecutive menstrual cycles. An impaired knee joint kinaesthesia was detected in the premenstrual phase and the performance of square hop test was significantly improved in the ovulation phase compared to the other two phases. The results of this study indicate that the variation of sex hormones in the menstrual cycle has an effect on performance of knee joint kinaesthesia and neuromuscular coordination.

Electromyographic activity of the diaphragm during neostigmine or sugammadex-enhanced recovery after neuromuscular blockade with rocuronium: a randomised controlled study in healthy volunteers.

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Schepens, Tom; Cammu, Guy; Saldien, Vera; De Neve, Nikolaas; Jorens, Philippe G; Foubert, Luc; Vercauteren, Marcel

2015-01-01

The use of neuromuscular blocking agents has been associated with severe postoperative respiratory morbidity. Complications can be attributed to inadequate reversal, and reversal agents may themselves have adverse effects. To compare the electromyographic activity of the diaphragm (EMGdi) during recovery from neuromuscular blockade using neostigmine and sugammadex. The hypothesis was that there would be better neuromuscular coupling of the diaphragm when sugammadex was used. A randomised, controlled, parallel-group, single-centre, double-blinded study. District general hospital in Belgium. Twelve healthy male volunteers. Individuals were anaesthetised with propofol and remifentanil. After rocuronium 0.6 mg kg, a transoesophageal electromyography (EMG) recorder was inserted. For reversal of neuromuscular blockade, volunteers received sugammadex 2 mg kg (n = 6) or neostigmine 70 μg kg (n = 6). EMGdi, airway pressure and flow were continuously measured during weaning from the ventilator until tracheal extubation. Arterial blood gas samples were obtained for PaO2 and PaCO2 analysis at the first spontaneous breathing attempt and after tracheal extubation. During weaning, 560 breaths were retained for analysis. The median (95% CI) peak EMGdi was 1.1 (0.9 to 1.5) μV in the neostigmine group and 1.6 (1.3 to 1.9) μV in the sugammadex group (P sugammadex group (P = 0.008). The median (95% CI) tidal volume was 287 (256 to 335) ml after neostigmine and 359 (313 to 398) ml after sugammadex (P = 0.013). The median (95% CI) PaO2 immediately after extubation was 30.5 (22.8 to 37.1) kPa after sugammadex vs. 20.7 (12.9 to 27.5) kPa after neostigmine (P = 0.03). EMGdi, tidal volume and PaO2 following tracheal extubation were increased after sugammadex compared with neostigmine, reflecting diaphragm-driven inspiration after sugammadex administration. Sugammadex may free more diaphragmatic acetylcholine receptors than neostigmine, which has an

Prevalence of IgE against neuromuscular blocking agents in hairdressers and bakers.

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Dong, S; Acouetey, D S; Guéant-Rodriguez, R-M; Zmirou-Navier, D; Rémen, T; Blanca, M; Mertes, P M; Guéant, J-L

2013-11-01

Allergic IgE-mediated reactions to neuromuscular blocking agents (NMBAs) are the main cause of immediate hypersensitivity reactions in anaesthesia; their predominant occurrence in the absence of previous exposure to NMBAs suggests a risk related to environmental exposure. To investigate the prevalence of specific IgE to quaternary ammonium ions in two populations professionally exposed to quaternary ammonium compounds, in the north-eastern France. The study had a retrospective follow-up design whereby apprentices were assessed after their 2-year training period as apprentices. The professionally exposed hairdresser populations (n = 128) were compared with baker/pastry makers (n = 108) and 'non-exposed' matched control subjects (n = 379). We observed a 4.6-fold higher frequency of positive IgE against quaternary ammonium ions in hairdressers (HD), compared with baker/pastry makers (BP) and control (C) groups. The competitive inhibition of quaternary ammonium Sepharose radioimmunoassay (QAS-IgE RIA) with succinylcholine was significantly higher in HD, compared with BP and C groups, with inhibition percentage of 66.2 ± 7.4, 39.7 ± 6.0 and 43.8 ± 9.9, respectively (P  100 kU/L were the two significant predictors of IgE-sensitization against quaternary ammonium ions in the multivariate analysis of a model that included age, sex, professional exposure, increased concentration of total IgE (IgE > 100 kU/L) and positive IgE against prevalent allergens (Phadiatop(®) ; P = 0.019 and P = 0.001, respectively). The exposure to hairdressing professional occupational factors increases IgE-sensitization to NMBAs and quaternary ammonium ion compounds used in hairdressing. Besides the pholcodine hypothesis, our study suggests that repetitive exposure to quaternary ammonium compounds used in hairdressing is a risk factor for NMBAs sensitization. © 2013 John Wiley & Sons Ltd.

Effect of Early Physical Activity Programs on Motor Performance and Neuromuscular Development in Infants Born Preterm: A Randomized Clinical Trial

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Leila Valizadeh

2017-03-01

Full Text Available Introduction: Although the survival rate of infants born preterm has increased, the prevalence of developmental problems and motor disorders among this population of infants remains the same. This study investigated the effect of physical activity programs in and out of water on motor performance and neuromuscular development of infants born preterm and had induced immobility by mechanical ventilation.Methods: This study was carried out in Al-Zahra hospital, Tabriz. 76 premature infants were randomly assigned into four groups. One group received daily passive range of motion to all extremities based on the Moyer-Mileur protocol. Hydrotherapy group received exercises for shoulders and pelvic area in water every other day. A combination group received physical activity programs in and out of water on alternating days. Infants in a containment group were held in a fetal position. Duration of study was two weeks ‘from 32 through 33 weeks post menstrual age (PMA. Motor outcomes were measured by the Test of Infant Motor Performance. Neuromuscular developmental was assessed by New Ballard scale and leg recoil and Ankle dorsiflexion items from Dubowitz scale. Data were analyzed using SPSS version 13.Results: TIMP and neuromuscular scores improved in all groups. Motor performance did not differ between groups at 34 weeks PMA. Postural tone of leg recoil was significantly higher in physical activity groups post intervention.Conclusion: Physical activities and containment didn’t have different effects on motor performance in infants born preterm. Leg recoil of neuromuscular development items was affected by physical activity programs.

Effects of neuromuscular training on knee joint stability after anterior cruciate ligament reconstruction.

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Shim, Jae-Kwang; Choi, Ho-Suk; Shin, Jun-Ho

2015-12-01

[Purpose] This study examined the effects of neuromuscular training on knee joint stability after anterior cruciate ligament reconstruction. [Subjects and Methods] The subjects were 16 adults who underwent arthroscopic anterior cruciate reconstruction and neuromuscular training. The Lysholm scale was used to assess functional disorders on the affected knee joint. A KT-2000 arthrometer was used to measure anterior displacement of the tibia against the femur. Surface electromyography was used to detect the muscle activation of the vastus medialis oblique, vastus lateralis, biceps femoris, and semitendinosus before and after neuromuscular training. [Results] There was significant relaxation in tibial anterior displacement of the affected and sound sides in the supine position before neuromuscular training. Furthermore, the difference in the tibial anterior displacement of the affected knee joints in the standing position was reduced after neuromuscular training. Moreover, the variation of the muscle activation evoked higher muscle activation of the vastus medialis oblique, vastus lateralis, biceps femoris, and semitendinosus. [Conclusion] Neuromuscular training may improve functional joint stability in patients with orthopedic musculoskeletal injuries in the postoperative period.

Cysteine reversal of the novel neuromuscular blocking drug CW002 in dogs: pharmacodynamics, acute cardiovascular effects, and preliminary toxicology.

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Sunaga, Hiroshi; Malhotra, Jaideep K; Yoon, Edward; Savarese, John J; Heerdt, Paul M

2010-04-01

CW002 is a neuromuscular blocking drug that is inactivated by endogenous L-cysteine. This study determined the exogenous L-cysteine dose-response relationship for CW002 reversal along with acute cardiovascular effects and organ toxicity in dogs. Six dogs were each studied four times during isoflurane-nitrous oxide anesthesia and recording of muscle twitch, arterial pressure, and heart rate. CW002 (0.08 mg/kg or 9 x ED95) was injected, and the time to spontaneous muscle recovery was determined. CW002 was then administered again followed 1 min later by 10, 20, 50, or 100 mg/kg L-cysteine (1 dose/experiment). After twitch recovery, CW002 was given a third time to determine whether residual L-cysteine influenced duration. Preliminary toxicology was performed in an additional group of dogs that received CW002 followed by vehicle (n = 8) or 200 mg/kg L-cysteine (n = 8). Animals were awakened and observed for 2 or 14 days before sacrificing and anatomic, biochemical, and histopathologic analyses. L-cysteine at all doses accelerated recovery from CW002, with both 50 and 100 mg/kg decreasing median duration from more than 70 min to less than 5 min. After reversal, duration of a subsequent CW002 dose was also decreased in a dose-dependent manner. Over the studied dose range, L-cysteine had less than 10% effect on blood pressure and heart rate. Animals receiving a single 200-mg/kg dose of L-cysteine showed no clinical, anatomic, biochemical, or histologic evidence of organ toxicity. The optimal L-cysteine dose for rapidly reversing the neuromuscular blockade produced by a large dose of CW002 in dogs is approximately 50 mg/kg, which has no concomitant hemodynamic effect. A dose of 200 mg/kg had no evident organ toxicity.

Effects of methylprednisolone on the duration of rocuronium-induced neuromuscular block

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Geng, Weilian; Nie, Yuyan; Huang, Shaoqiang

2017-01-01

Abstract Background: We aim to investigate whether intraoperative use of methylprednisolone could affect the duration of rocuronium-induced neuromuscular blockade. Methods: A double blind, randomized, placebo-controlled trial was conducted. A total of 136 patients underwent gynecologic laparoscopic surgery were randomly divided into 3 groups: pregroup, receiving intravenous injection of methylprednisolone (40 mg) 30 minutes before induction of anesthesia; postgroup, receiving intravenous injection of methylprednisolone (40 mg) immediately after induction of anesthesia and intubation; and control group, receiving intravenous injection of normal saline. Patients were intravenously administrated with rocuronium 0.6 mg/kg, and changes in adductor policies evoked twitch responses were measured by ulnar nerve stimulator. Results: We found that all patients achieved maximum blockade effects, and there was no difference in onset time among the 2 groups. For time required to achieve train-of-four ratio (TOFR) 90%, pregroup (64.50 ± 10.52 minutes) and postgroup (65.29 ± 11.64 minutes) were significantly shorter than that of the control group (71.04 ± 10.55 minutes, P = .027), whereas clinical duration and total duration were significantly shorter in the 2 groups received methylprednisolone than the control group. However, there was no significant difference between the 2 treatment groups either in clinical duration and total duration of muscle relaxants, or time required to achieve TOFR 90%. No significant difference was found in recovery index among the 3 groups. Conclusion: Our findings suggest that a single intravenous injection of methylprednisolone, no matter preoperatively or intraoperatively, could shorten the duration of rocuronium-induced neuromuscular blockade. PMID:28953616

Knee and Hip Joint Kinematics Predict Quadriceps and Hamstrings Neuromuscular Activation Patterns in Drop Jump Landings.

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Malfait, Bart; Dingenen, Bart; Smeets, Annemie; Staes, Filip; Pataky, Todd; Robinson, Mark A; Vanrenterghem, Jos; Verschueren, Sabine

2016-01-01

The purpose was to assess if variation in sagittal plane landing kinematics is associated with variation in neuromuscular activation patterns of the quadriceps-hamstrings muscle groups during drop vertical jumps (DVJ). Fifty female athletes performed three DVJ. The relationship between peak knee and hip flexion angles and the amplitude of four EMG vectors was investigated with trajectory-level canonical correlation analyses over the entire time period of the landing phase. EMG vectors consisted of the {vastus medialis(VM),vastus lateralis(VL)}, {vastus medialis(VM),hamstring medialis(HM)}, {hamstring medialis(HM),hamstring lateralis(HL)} and the {vastus lateralis(VL),hamstring lateralis(HL)}. To estimate the contribution of each individual muscle, linear regressions were also conducted using one-dimensional statistical parametric mapping. The peak knee flexion angle was significantly positively associated with the amplitudes of the {VM,HM} and {HM,HL} during the preparatory and initial contact phase and with the {VL,HL} vector during the peak loading phase (phamstrings medialis activity) during the preparatory and initial contact phase and an increased lateral neuromuscular activation (dominant vastus lateralis activity) during the peak loading phase.

Rocuronium and sugammadex in a 3 days old neonate for draining an ovarian cyst. Neuromuscular management and review of the literature

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Ricardo Vieira Carlos

2016-07-01

Full Text Available A case is reported in which a 3-days old neonate with a giant ovarian cyst was scheduled for surgery. The patient received a dose of sugammadex to reverse a rocuronium-induced neuromuscular block. A fast and efficient recovery from neuromuscular block was achieved within 90 s. No adverse events or other safety concerns were observed. Furthermore, a review of the literature on the use of sugammadex in neonates was performed. Resumo: Relato do caso de uma criança recém-nascida de 3 dias de idade com um cisto ovariano gigante programada para a cirurgia. A paciente recebeu uma dose de sugamadex para reverter o bloqueio neuromuscular induzido por rocurônio. Uma recuperação rápida e eficiente do bloqueio neuromuscular foi obtida dentro de 90 segundos. Não foram observados efeitos adversos ou outros problemas de segurança. Além disso, uma revisão da literatura sobre o uso de sugamadex em recém-nascidos foi realizada. Keywords: Neonates, Ovarian cyst, Sugammadex, Rocuronium, Reversal agent, Palavras-chave: Recém-nascidos, Cisto ovariano, Sugammadex, Rocurônio, Agente de reversão

Active zones of mammalian neuromuscular junctions: formation, density, and aging.

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Nishimune, Hiroshi

2012-12-01

Presynaptic active zones are synaptic vesicle release sites that play essential roles in the function and pathology of mammalian neuromuscular junctions (NMJs). The molecular mechanisms of active zone organization use presynaptic voltage-dependent calcium channels (VDCCs) in NMJs as scaffolding proteins. VDCCs interact extracellularly with the muscle-derived synapse organizer, laminin β2 and interact intracellularly with active zone-specific proteins, such as Bassoon, CAST/Erc2/ELKS2alpha, ELKS, Piccolo, and RIMs. These molecular mechanisms are supported by studies in P/Q- and N-type VDCCs double-knockout mice, and they are consistent with the pathological conditions of Lambert-Eaton myasthenic syndrome and Pierson syndrome, which are caused by autoantibodies against VDCCs or by a laminin β2 mutation. During normal postnatal maturation, NMJs maintain the density of active zones, while NMJs triple their size. However, active zones become impaired during aging. Propitiously, muscle exercise ameliorates the active zone impairment in aged NMJs, which suggests the potential for therapeutic strategies. © 2012 New York Academy of Sciences.

Acute fatigue impairs neuromuscular activity of anterior cruciate ligament-agonist muscles in female team handball players.

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Zebis, M K; Bencke, J; Andersen, L L; Alkjaer, T; Suetta, C; Mortensen, P; Kjaer, M; Aagaard, P

2011-12-01

In sports, like team handball, fatigue has been associated with an increased risk of anterior cruciate ligament (ACL) injury. While effects of fatigue on muscle function are commonly assessed during maximal isometric voluntary contraction (MVC), such measurements may not relate to the muscle function during match play. The purpose of this study was to investigate the effect of muscle fatigue induced by a simulated handball match on neuromuscular strategy during a functional sidecutting movement, associated with the incidence of ACL injury. Fourteen female team handball players were tested for neuromuscular activity [electromyography (EMG)] during a sidecutting maneuver on a force plate, pre and post a simulated handball match. MVC was obtained during maximal isometric quadriceps and hamstring contraction. The simulated handball match consisted of exercises mimicking handball match activity. Whereas the simulated handball match induced a decrease in MVC strength for both the quadriceps and hamstring muscles (Phandball match play. Thus, screening procedures should involve functional movements to reveal specific fatigue-induced deficits in ACL-agonist muscle activation during high-risk phases of match play. © 2010 John Wiley & Sons A/S.

The effects of two phospholipase A2 inhibitors on the neuromuscular blocking activities of homologous phospholipases A2 from the venom of Pseudechis australis, the Australian king brown snake.

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Fatehi, M; Rowan, E G; Harvey, A L

1995-12-01

Previous studies have shown that homologous phospholipases A2 (PLA2) (Pa-3, Pa-9C, Pa-10F and Pa-11) from the venom of the Australian king brown snake, Pseudechis australis, significantly reduce the resting membrane potentials and quantal contents of endplate potentials recorded from endplate regions of mouse triangularis sterni nerve-muscle preparations. It is not clear whether PLA2 activity is essential for their neuromuscular activities. Therefore, pharmacological studies were carried out to determine whether neuromuscular activity of the toxins changed after treatment with the phospholipase A2 inhibitors 7,7-dimethyl-eicosadienoic acid (DEDA) and manoalide. After incubation of the toxins with manoalide (120 nM), or DEDA (50 microM), no PLA2 activity against 1-stearoyl 2-[3H]arachidonoylglycerophosphocholine was detected. After incubation with manoalide and/or DEDA, the toxins did not depolarize muscle fibre membranes up to 60 min after administration. However, manoalide and DEDA had different influences on the inhibitory effect of these toxic enzymes on acetylcholine release from nerve terminals. Manoalide abolished the inhibitory effect of the toxins on evoked release of acetylcholine. In contrast, DEDA was not able to prevent the reduction of quantal content of endplate potentials induced by the toxins. This study provides evidence that the depolarizing action and the inhibitory effect on release of acetylcholine exerted by these toxic PLA2 from king brown snake are independent phenomena. The evidence for this conclusion was that inhibition of enzymatic activity with an arachidonic acid analogue (DEDA) abolished the depolarizing effect of the toxins but not the effects on the quantal release of acetylcholine from mouse motor nerve terminals. The data suggest that the depolarizing effect of these toxins is probably due to the enzymatic activity. Since manoalide interacts with lysine residues of PLA2 polypeptides, and, as shown here, manoalide prevented

TEACHING NEUROMUSCULAR RELAXATION.

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NORRIS, JEANNE E.; STEINHAUS, ARTHUR H.

THIS STUDY ATTEMPTED TO FIND OUT WHETHER (1) THE METHODS FOR ATTAINING NEUROMUSCULAR RELAXATION THAT HAVE PROVED FRUITFUL IN THE ONE-TO-ONE RELATIONSHIP OF THE CLINIC CAN BE SUCCESSFULLY ADAPTED TO THE TEACHER-CLASS RELATIONSHIP OF THE CLASSROOM AND GYMNASIUM, AND (2) NEUROMUSCULAR RELAXATION CAN BE TAUGHT SUCCESSFULLY BY AN APPROPRIATELY TRAINED…

Neuromuscular complications of thyrotoxicosis.

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Kung, Annie W C

2007-11-01

Thyroid hormones exert multiple effects on the neuromuscular system and the brain, with the most important being their role in stimulating the development and differentiation of the neuromuscular system and brain in foetal and neonatal life. In the presence of hyperthyroidism, muscular and neurological symptoms may be the presenting clinical features of the disease. The frequency and severity of neuromuscular complications vary considerably and are probably related to the degree of hyperthyroidism, although in some patients the neuromuscular dysfunction is caused by associated disorders rather than by hyperthyroidism per se. This update focuses on the most common neurological and muscular disorders that occur in patients with thyrotoxicosis. It is beyond the scope of this paper to discuss thyroid eye disease and cardiac complications, in themselves separate complications of specific myocytes.

Reversal of neuromuscular blockade with sugammadex or neostigmine/atropine: Effect on postoperative gastrointestinal motility.

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Sen, A; Erdivanli, B; Tomak, Y; Pergel, A

2016-08-01

To compare sugammadex with conventional reversal of neuromuscular block in terms of postoperative gastrointestinal motility. Double blinded, randomized, controlled clinical trial. Operating room, postoperative recovery area. Seventy-two patients with ASA physical status I or II, scheduled for total thyroid surgery were studied. When 4 twitches were observed on train-of-four stimulation, neuromuscular block was reversed conversatively in the control group, and with sugammadex in the study group. Time to first flatus and feces, incidence of postoperative nausea, vomiting, diarrhea and constipation were collected. Median time of first flatus was 24 hours (18-32 [10-36]) in the neostigmine group, and 24 (18-28 [12-48]) in the sugammadex group (P > .05). Median (IQR) time of first feces was 24 hours (18-36 [10-48]) in neostigmine group, 32 hours (28-36 [12-72]) in sugammadex group (P > .05). There were no occurrences of nausea, vomiting, diarrhea, or constipation. Sugammadex may be safely used in cases where postoperative ileus is expected. Copyright © 2016 Elsevier Inc. All rights reserved.

17β-Estradiol Induced Effects on Anterior Cruciate Ligament Laxness and Neuromuscular Activation Patterns in Female Runners.

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Khowailed, Iman Akef; Petrofsky, Jerrold; Lohman, Everett; Daher, Noha; Mohamed, Olfat

2015-08-01

We investigate the effects of 17β-Estradiol across phases of menstrual cycle on the laxness of the anterior cruciate ligament (ACL) and the neuromuscular control patterns around the knee joint in female runners. Twelve healthy female runners who reported normal menstrual cycles for the previous 6 months were tested twice across one complete menstrual cycle for serum levels of 17β-estradiol, and knee joint laxity (KJL). Electromyographic (EMG) activity of the quadriceps and hamstrings muscles was also recorded during running on a treadmill. The changes in the EMG activity, KJL, and hormonal concentrations were recorded for each subject during the follicular and the ovulatory phases across the menstrual cycle. An observed increase in KJL in response to peak estradiol during the ovulatory phase was associated with increased preactivity of the hamstring muscle before foot impact (pneuromuscular control around the knee during running. Female runners utilize different neuromuscular control strategies during different phases of the menstrual cycle, which may contribute to increased ACL injury risk.

Neuromuscular blockade of slow twitch muscle fibres elevates muscle oxygen uptake and energy turnover during submaximal exercise in humans

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Krustrup, Peter; Secher, Niels; Relu, Mihai U.

2008-01-01

We tested the hypothesis that a greater activation of fast-twitch (FT) fibres during dynamic exercise leads to a higher muscle oxygen uptake (VO2 ) and energy turnover as well as a slower muscle on-kinetics. Subjects performed one-legged knee-extensor exercise for 10 min at an intensity of 30 W...... without (CON) and with (CUR) arterial injections of the non-depolarizing neuromuscular blocking agent cisatracurium. In CUR, creatine phosphate (CP) was unaltered in slow twitch (ST) fibres and decreased (P fibres, whereas in CON, CP decreased (P ... at a contraction frequency of 1 Hz, and that the muscle VO2 kinetics is slowed by FT fibre activation....

Hereditary neuromuscular diseases

Energy Technology Data Exchange (ETDEWEB)

Oezsarlak, O. E-mail: ozkan.ozsarlak@uza.be; Schepens, E.; Parizel, P.M.; Goethem, J.W. van; Vanhoenacker, F.; Schepper, A.M. de; Martin, J.J

2001-12-01

This article presents the actual classification of neuromuscular diseases based on present expansion of our knowledge and understanding due to genetic developments. It summarizes the genetic and clinical presentations of each disorder together with CT findings, which we studied in a large group of patients with neuromuscular diseases. The muscular dystrophies as the largest and most common group of hereditary muscle diseases will be highlighted by giving detailed information about the role of CT and MRI in the differential diagnosis. The radiological features of neuromuscular diseases are atrophy, hypertrophy, pseudohypertrophy and fatty infiltration of muscles on a selective basis. Although the patterns and distribution of involvement are characteristic in some of the diseases, the definition of the type of disease based on CT scan only is not always possible.

Neuromuscular interactions around the knee in children, adults and elderly

Science.gov (United States)

Kellis, Eleftherios; Mademli, Lida; Patikas, Dimitrios; Kofotolis, Nikolaos

2014-01-01

Although injury and neuromuscular activation patterns may be common for all individuals, there are certain factors which differentiate neuromuscular activity responses between children, adults and elderly. The purpose of this study is to review recent evidence on age differences in neural activation and muscle balances around the knee when performing single joint movements. Particularly, current evidence indicates that there are some interesting similarities in the neuromuscular mechanisms by which children or the elderly differ compared with adults. Both children and elderly display a lower absolute muscle strength capacity than adults which cannot fully be explained by differences in muscle mass. Quadriceps activation failure is a common symptom of all knee injuries, irrespective of age but it is likely that its effect is more evident in children or adults. While one might expect that antagonist co-activation would differ between age categories, it appears that this is not the case. Although hamstring: quadriceps ratio levels are altered after knee injury, it is not clear whether this is an age specific response. Finally, evidence suggests that both children and the elderly display less stiffness of the quadriceps muscle-tendon unit than adults which affects their knee joint function. PMID:25232523

Rapid synthesis of acetylcholine receptors at neuromuscular junctions.

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Ramsay, D A; Drachman, D B; Pestronk, A

1988-10-11

The rate of acetylcholine receptor (AChR) degradation in mature, innervated mammalian neuromuscular junctions has recently been shown to be biphasic; up to 20% are rapidly turned over (RTOs; half life less than 1 day) whereas the remainder are lost more slowly ('stable' AChRs; half life 10-12 days). In order to maintain normal junctional receptor density, synthesis and insertion of AChRs should presumably be sufficiently rapid to replace both the RTOs and the stable receptors. We have tested this prediction by blocking pre-existing AChRs in the mouse sternomastoid muscle with alpha-bungarotoxin (alpha-BuTx), and monitoring the subsequent appearance of 'new' junctional AChRs at intervals of 3 h to 20 days by labeling them with 125I-alpha-BuTx. The results show that new receptors were initially inserted rapidly (16% at 24 h and 28% at 48 h). The rate of increase of 'new' 125I-alpha-BuTx binding sites gradually slowed down during the remainder of the time period studied. Control observations excluded possible artifacts of the experimental procedure including incomplete blockade of AChRs, dissociation of toxin-receptor complexes, or experimentally induced alteration of receptor synthesis. The present demonstration of rapid synthesis and incorporation of AChRs at innervated neuromuscular junctions provides support for the concept of a subpopulation of rapidly turned over AChRs. The RTOs may serve as precursors for the larger population of stable receptors and have an important role in the metabolism of the neuromuscular synapse.

Adenosine A₁ and A₂A receptor-mediated modulation of acetylcholine release in the mice neuromuscular junction.

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Garcia, Neus; Priego, Mercedes; Obis, Teresa; Santafe, Manel M; Tomàs, Marta; Besalduch, Nuria; Lanuza, M Angel; Tomàs, Josep

2013-07-01

Immunocytochemistry shows that purinergic receptors (P1Rs) type A1 and A2A (A1 R and A2 A R, respectively) are present in the nerve endings at the P6 and P30 Levator auris longus (LAL) mouse neuromuscular junctions (NMJs). As described elsewhere, 25 μm adenosine reduces (50%) acetylcholine release in high Mg(2+) or d-tubocurarine paralysed muscle. We hypothesize that in more preserved neurotransmission machinery conditions (blocking the voltage-dependent sodium channel of the muscle cells with μ-conotoxin GIIIB) the physiological role of the P1Rs in the NMJ must be better observed. We found that the presence of a non-selective P1R agonist (adenosine) or antagonist (8-SPT) or selective modulators of A1 R or A2 A R subtypes (CCPA and DPCPX, or CGS-21680 and SCH-58261, respectively) does not result in any changes in the evoked release. However, P1Rs seem to be involved in spontaneous release (miniature endplate potentials MEPPs) because MEPP frequency is increased by non-selective block but decreased by non-selective stimulation, with A1 Rs playing the main role. We assayed the role of P1Rs in presynaptic short-term plasticity during imposed synaptic activity (40 Hz for 2 min of supramaximal stimuli). Depression is reduced by micromolar adenosine but increased by blocking P1Rs with 8-SPT. Synaptic depression is not affected by the presence of selective A1 R and A2 A R modulators, which suggests that both receptors need to collaborate. Thus, A1 R and A2 A R might have no real effect on neuromuscular transmission in resting conditions. However, these receptors can conserve resources by limiting spontaneous quantal leak of acetylcholine and may protect synaptic function by reducing the magnitude of depression during repetitive activity. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

The effects of neuromuscular training on knee joint motor control during sidecutting in female elite soccer and handball players.

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Zebis, Mette K; Bencke, Jesper; Andersen, Lars L; Døssing, Simon; Alkjaer, Tine; Magnusson, S Peter; Kjaer, Michael; Aagaard, Per

2008-07-01

The project aimed to implement neuromuscular training during a full soccer and handball league season and to experimentally analyze the neuromuscular adaptation mechanisms elicited by this training during a standardized sidecutting maneuver known to be associated with non-contact anterior cruciate ligament (ACL) injury. The players were tested before and after 1 season without implementation of the prophylactic training and subsequently before and after a full season with the implementation of prophylactic training. A total of 12 female elite soccer players and 8 female elite team handball players aged 26 +/- 3 years at the start of the study. The subjects participated in a specific neuromuscular training program previously shown to reduce non-contact ACL injury. Neuromuscular activity at the knee joint, joint angles at the hip and knee, and ground reaction forces were recorded during a sidecutting maneuver. Neuromuscular activity in the prelanding phase was obtained 10 and 50 ms before foot strike on a force plate and at 10 and 50 ms after foot strike on a force plate. Neuromuscular training markedly increased before activity and landing activity electromyography (EMG) of the semitendinosus (P Neuromuscular training increased EMG activity for the medial hamstring muscles, thereby decreasing the risk of dynamic valgus. This observed neuromuscular adaptation during sidecutting could potentially reduce the risk for non-contact ACL injury.

Presynaptic active zones of mammalian neuromuscular junctions: Nanoarchitecture and selective impairments in aging.

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Badawi, Yomna; Nishimune, Hiroshi

2018-02-01

Neurotransmitter release occurs at active zones, which are specialized regions of the presynaptic membrane. A dense collection of proteins at the active zone provides a platform for molecular interactions that promote recruitment, docking, and priming of synaptic vesicles. At mammalian neuromuscular junctions (NMJs), muscle-derived laminin β2 interacts with presynaptic voltage-gated calcium channels to organize active zones. The molecular architecture of presynaptic active zones has been revealed using super-resolution microscopy techniques that combine nanoscale resolution and multiple molecular identification. Interestingly, the active zones of adult NMJs are not stable structures and thus become impaired during aging due to the selective degeneration of specific active zone proteins. This review will discuss recent progress in the understanding of active zone nanoarchitecture and the mechanisms underlying active zone organization in mammalian NMJs. Furthermore, we will summarize the age-related degeneration of active zones at NMJs, and the role of exercise in maintaining active zones. Copyright © 2017 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Lumbopelvic flexibility modulates neuromuscular responses during trunk flexion-extension.

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Sánchez-Zuriaga, Daniel; Artacho-Pérez, Carla; Biviá-Roig, Gemma

2016-06-01

Various stimuli such as the flexibility of lumbopelvic structures influence the neuromuscular responses of the trunk musculature, leading to different load sharing strategies and reflex muscle responses from the afferents of lumbopelvic mechanoreceptors. This link between flexibility and neuromuscular response has been poorly studied. The aim of this study was to investigate the relationship between lumbopelvic flexibility and neuromuscular responses of the erector spinae, hamstring and abdominal muscles during trunk flexion-extension. Lumbopelvic movement patterns were measured in 29 healthy women, who were separated into two groups according to their flexibility during trunk flexion-extension. The electromyographic responses of erector spinae, rectus abdominis and biceps femoris were also recorded. Subjects with greater lumbar flexibility had significantly less pelvic flexibility and vice versa. Subjects with greater pelvic flexibility had a higher rate of relaxation and lower levels of hamstring activation during maximal trunk flexion. The neuromuscular response patterns of the hamstrings seem partially modulated by pelvic flexibility. Not so with the lumbar erector spinae and lumbar flexibility, despite the assertions of some previous studies. The results of this study improve our knowledge of the relationships between trunk joint flexibility and neuromuscular responses, a relationship which may play a role in low back pain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Robotic assessment of neuromuscular characteristics using musculoskeletal models: A pilot study.

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Jayaneththi, V R; Viloria, J; Wiedemann, L G; Jarrett, C; McDaid, A J

2017-07-01

Non-invasive neuromuscular characterization aims to provide greater insight into the effectiveness of existing and emerging rehabilitation therapies by quantifying neuromuscular characteristics relating to force production, muscle viscoelasticity and voluntary neural activation. In this paper, we propose a novel approach to evaluate neuromuscular characteristics, such as muscle fiber stiffness and viscosity, by combining robotic and HD-sEMG measurements with computational musculoskeletal modeling. This pilot study investigates the efficacy of this approach on a healthy population and provides new insight on potential limitations of conventional musculoskeletal models for this application. Subject-specific neuromuscular characteristics of the biceps and triceps brachii were evaluated using robot-measured kinetics, kinematics and EMG activity as inputs to a musculoskeletal model. Repeatability experiments in five participants revealed large variability within each subjects evaluated characteristics, with almost all experiencing variation greater than 50% of full scale when repeating the same task. The use of robotics and HD-sEMG, in conjunction with musculoskeletal modeling, to quantify neuromuscular characteristics has been explored. Despite the ability to predict joint kinematics with relatively high accuracy, parameter characterization was inconsistent i.e. many parameter combinations gave rise to minimal kinematic error. The proposed technique is a novel approach for in vivo neuromuscular characterization and is a step towards the realization of objective in-home robot-assisted rehabilitation. Importantly, the results have confirmed the technical (robot and HD-sEMG) feasibility while highlighting the need to develop new musculoskeletal models and optimization techniques capable of achieving consistent results across a range of dynamic tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neuromuscular adaptations to training, injury and passive interventions: implications for running economy.

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Bonacci, Jason; Chapman, Andrew; Blanch, Peter; Vicenzino, Bill

2009-01-01

has also been observed. Muscle activity during running after cycling has yet to be fully investigated, and to date, the effect of alterations in muscle coordination on running economy is largely unknown. Stretching, which is another mode of training, may induce acute neuromuscular effects but does not appear to alter running economy. There are also factors other than training structure that may influence running economy and neuromuscular adaptations. For example, passive interventions such as shoes and in-shoe orthoses, as well as the presence of musculoskeletal injury, may be considered important modulators of neuromuscular control and run performance. Alterations in muscle activity and running economy have been reported with different shoes and in-shoe orthoses; however, these changes appear to be subject-specific and non-systematic. Musculoskeletal injury has been associated with modifications in lower limb neuromuscular control, which may persist well after an athlete has returned to activity. The influence of changes in neuromuscular control as a result of injury on running economy has yet to be examined thoroughly, and should be considered in future experimental design and training analysis.

Influência da nifedipina no bloqueio neuromuscular produzido pelo atracúrio e pelo cisatracúrio: estudo em preparações nervo frênico-diafragma de rato Influencia de la nifedipina en el bloqueo neuromuscular producido por atracurio y cisatracurio: estudio en preparación nervio frénico diafragma de ratón Influence of nifedipine on the neuromuscular block produced by atracurium and cistracurium: study in rat phrenic-diaphragmatic nerve preparation

Directory of Open Access Journals (Sweden)

Silmara Rodrigues de Sousa

2006-04-01

significantly increase the neuromuscular blocking activity of atracurium and cistracurium. Nifedipine did not alter the membrane potential and caused an initial increase on MEPP frequencies, followed by a blockage. CONCLUSIONS: Nifedipine, on the employed concentration, increased the neuromuscular blockage produced by atracurium and cistracurium. Electrophysiological studies demonstrate the existence of presynaptic action and absence of depolarizing action over the muscle fiber.

Sugammadex antagonism of rocuronium-induced neuromuscular blockade in patients with liver cirrhosis undergoing liver resection: a randomized controlled study.

Science.gov (United States)

Abdulatif, Mohamed; Lotfy, Maha; Mousa, Mahmoud; Afifi, Mohamed H; Yassen, Khaled

2018-02-05

This randomized controlled study compared the recovery times of sugammadex and neostigmine as antagonists of moderate rocuroniuminduced neuromuscular block in patients with liver cirrhosis and controls undergoing liver resection. The study enrolled 27 adult patients with Child class "A" liver cirrhosis and 28 patients with normal liver functions. Normal patients and patients with liver cirrhosis were randomized according to the type of antagonist (sugammadex 2mg/kg or neostigmine 50μg/kg). The primary outcome was the time from antagonist administration to a trainoffour (TOF) ratio of 0.9 using mechanosensor neuromuscular transmission module. The durations of the intubating and topup doses of rocuronium, the length of stay in the postanesthesia care unit (PACU), and the incidence of postoperative re curarization were recorded. The durations of the intubating and topup doses of rocuronium were prolonged in patients with liver cirrhosis than controls. The times to a TOF ratio of 0.9 were 3.1 (1.0) and 2.6 (1.0) min after sugammadex administration in patients with liver cirrhosis and controls, respectively, p=1.00. The corresponding times after neostigmine administration were longer than sugammadex 14.5 (3.6) and 15.7 (3.6) min, respectively, psugammadex compared to neostigmine. We did not encounter postoperative recurarization after sugammadex or neostigmine. Sugammadex rapidly antagonize moderate residual rocuronium induced neuromuscular block in patients with Child class "A" liver cirrhosis undergoing liver resection. Sugammadex antagonism is associated with 80% reduction in the time to adequate neuromuscular recovery compared to neostigmine.

Improving Neuromuscular Monitoring and Reducing Residual Neuromuscular Blockade With E-Learning

DEFF Research Database (Denmark)

Thomsen, Jakob Louis Demant; Mathiesen, Ole; Hägi-Pedersen, Daniel

2017-01-01

BACKGROUND: Muscle relaxants facilitate endotracheal intubation under general anesthesia and improve surgical conditions. Residual neuromuscular blockade occurs when the patient is still partially paralyzed when awakened after surgery. The condition is associated with subjective discomfort and an......-learning module can increase anesthetists' use of neuromuscular monitoring. TRIAL REGISTRATION: Clinicaltrials.gov NCT02925143; https://clinicaltrials.gov/ct2/show/NCT02925143 (Archived by WebCite® at http://www.webcitation.org/6s50iTV2x)....

Negative Pressure Pulmonary Edema after Reversing Rocuronium-Induced Neuromuscular Blockade by Sugammadex

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Manzo Suzuki

2014-01-01

Full Text Available Negative pressure pulmonary edema (NPPE is a rare complication that accompanies general anesthesia, especially after extubation. We experienced a case of negative pressure pulmonary edema after tracheal extubation following reversal of rocuronium-induced neuromuscular blockade by sugammadex. In this case, the contribution of residual muscular block on the upper airway muscle as well as large inspiratory forces created by the respiratory muscle which has a low response to muscle relaxants, is suspected as the cause.

Autosomal-dominant non-autoimmune hyperthyroidism presenting with neuromuscular symptoms.

Science.gov (United States)

Elgadi, Aziz; Arvidsson, C-G; Janson, Annika; Marcus, Claude; Costagliola, Sabine; Norgren, Svante

2005-08-01

Neuromuscular presentations are common in thyroid disease, although the mechanism is unclear. In the present study, we investigated the pathogenesis in a boy with autosomal-dominant hyperthyroidism presenting with neuromuscular symptoms. The TSHr gene was investigated by direct sequencing. Functional properties of the mutant TSHr were investigated during transient expression in COS-7 cells. Family members were investigated by clinical and biochemical examinations. Sequence analysis revealed a previously reported heterozygous missense mutation Glycine 431 for Serine in the first transmembrane segment, leading to an increased specific constitutive activity. Three additional affected family members carried the same mutation. There was no indication of autoimmune disorder. All symptoms disappeared upon treatment with thacapzol and L-thyroxine and subsequent subtotal thyroidectomy. The data imply that neuromuscular symptoms can be caused by excessive thyroid hormone levels rather than by autoimmunity.

Bilateral neuromuscular and force differences during a plyometric task.

Science.gov (United States)

Ball, Nick B; Scurr, Joanna C

2009-08-01

The purpose of this article is to compare the bilateral neuromuscular and force contribution during a plyometric bounce drop jump task and to assess the affects of nonsimultaneous foot placement. Sixteen male participants performed bounce drop jumps from a height of 0.4 m. Mean peak electromyography activity of the soleus, medial, and lateral gastrocnemius of both legs was recorded from each phase of the drop jump and normalized to a reference dynamic muscle action. Resultant ground reaction force, ground contact time, and duration of the drop jumps were recorded from each leg. Multivariate analysis of variance was used to compare bilateral electromyographic activity, resultant peak ground reaction force, and contact duration. Pearson's correlations (r) ascertained relationships between normalized electromyographic activity and contact time. Significant differences were shown between left and right triceps surae normalized electromyography during precontact and contact40ms (p 0.01). Significant differences were found between normalized soleus electromyography and both gastrocnemii for both legs during precontact (p 0.01). Weak relationships were found between normalized electromyographic activity and nonsimultaneous foot contact (r < 0.2). This study showed differences between left and right triceps surae in neuromuscular strategies engaged in the early stages of a drop jump task. Differences in contact time initiation were present; however, they are not significant enough to cause neuromuscular differences in the plantar flexor muscles.

Effectiveness of Neuromuscular Training Based on the Neuromuscular Risk Profile.

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Hewett, Timothy E; Ford, Kevin R; Xu, Yingying Y; Khoury, Jane; Myer, Gregory D

2017-07-01

The effects of targeted neuromuscular training (TNMT) on movement biomechanics associated with the risk of anterior cruciate ligament (ACL) injuries are currently unknown. Purpose/Hypotheses: To determine the effectiveness of TNMT specifically designed to increase trunk control and hip strength. The hypotheses were that (1) TNMT would decrease biomechanical and neuromuscular factors related to an increased ACL injury risk and (2) TNMT would decrease these biomechanical and neuromuscular factors to a greater extent in athletes identified as being at a high risk for future ACL injuries. Controlled laboratory study. Female athletes who participated in jumping, cutting, and pivoting sports underwent 3-dimensional biomechanical testing before the season and after completing TNMT. During testing, athletes performed 3 different types of tasks: (1) drop vertical jump, (2) single-leg drop, and (3) single-leg cross drop. Analysis of covariance was used to examine the treatment effects of TNMT designed to enhance core and hip strength on biomechanical and neuromuscular characteristics. Differences were also evaluated by risk profile. Differences were considered statistically significant at P risk before the intervention (risk profile III) had a more significant treatment effect of TNMT than low-risk groups (risk profiles I and II). TNMT significantly improved proximal biomechanics, including increased hip external rotation moments and moment impulses, increased peak trunk flexion, and decreased peak trunk extension. TNMT that focuses exclusively on proximal leg and trunk risk factors is not, however, adequate to induce significant changes in frontal-plane knee loading. Biomechanical changes varied across the risk profile groups, with higher risk groups exhibiting greater improvements in their biomechanics.

Reclassifying Anaphylaxis to Neuromuscular Blocking Agents Based on the Presumed Patho-Mechanism: IgE-Mediated, Pharmacological Adverse Reaction or “Innate Hypersensitivity”?

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David Spoerl

2017-06-01

Full Text Available Approximately 60% of perioperative anaphylactic reactions are thought to be immunoglobulin IgE mediated, whereas 40% are thought to be non-IgE mediated hypersensitivity reactions (both considered non-dose-related type B adverse drug reactions. In both cases, symptoms are elicited by mast cell degranulation. Also, pharmacological reactions to drugs (type A, dose-related may sometimes mimic symptoms triggered by mast cell degranulation. In case of hypotension, bronchospasm, or urticarial rash due to mast cell degranulation, identification of the responsible mechanism is complicated. However, determination of the type of the underlying adverse drug reaction is of paramount interest for the decision of whether the culprit drug may be re-administered. Neuromuscular blocking agents (NMBA are among the most frequent cause of perioperative anaphylaxis. Recently, it has been shown that NMBA may activate mast cells independently from IgE antibodies via the human Mas-related G-protein-coupled receptor member X2 (MRGPRX2. In light of this new insight into the patho-mechanism of pseudo-allergic adverse drug reactions, in which as drug-receptor interaction results in anaphylaxis like symptoms, we critically reviewed the literature on NMBA-induced perioperative anaphylaxis. We challenge the dogma that NMBA mainly cause IgE-mediated anaphylaxis via an IgE-mediated mechanism, which is based on studies that consider positive skin test to be specific for IgE-mediated hypersensitivity. Finally, we discuss the question whether MRGPRX2 mediated pseudo-allergic reactions should be re-classified as type A adverse reactions.

[Respiratory treatments in neuromuscular disease].

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Martínez Carrasco, C; Cols Roig, M; Salcedo Posadas, A; Sardon Prado, O; Asensio de la Cruz, O; Torrent Vernetta, A

2014-10-01

In a previous article, a review was presented of the respiratory pathophysiology of the patient with neuromuscular disease, as well as their clinical evaluation and the major complications causing pulmonary deterioration. This article presents the respiratory treatments required to preserve lung function in neuromuscular disease as long as possible, as well as in special situations (respiratory infections, spinal curvature surgery, etc.). Special emphasis is made on the use of non-invasive ventilation, which is changing the natural history of many of these diseases. The increase in survival and life expectancy of these children means that they can continue their clinical care in adult units. The transition from pediatric care must be an active, timely and progressive process. It may be slightly stressful for the patient before the adaptation to this new environment, with multidisciplinary care always being maintained. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Neuromuscular performance in the hip joint of elderly fallers and non-fallers.

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Morcelli, Mary Hellen; LaRoche, Dain Patrick; Crozara, Luciano Fernandes; Marques, Nise Ribeiro; Hallal, Camilla Zamfolini; Rossi, Denise Martineli; Gonçalves, Mauro; Navega, Marcelo Tavella

2016-06-01

Low strength and neuromuscular activation of the lower limbs have been associated with falls making it an important predictor of functional status in the elderly. To compare the rate of neuromuscular activation, rate of torque development, peak torque and reaction time between young and elderly fallers and non-fallers for hip flexion and extension. We evaluated 44 elderly people who were divided into two groups: elderly fallers (n = 20) and elderly non-fallers (n = 24); and 18 young people. The subjects performed three isometric hip flexion and extension contractions. Electromyography data were collected for the rectus femoris, gluteus maximus and biceps femoris muscles. The elderly had 49 % lower peak torque and 68 % lower rate of torque development for hip extension, 28 % lower rate of neuromuscular activation for gluteus maximus and 38 % lower rate of neuromuscular activation for biceps femoris than the young (p neuromuscular for rectus femoris than the young (p < 0.05). The elderly fallers showed consistent trend toward a lower rate of torque development than elderly non-fallers for hip extension at 50 ms (29 %, p = 0.298, d = 0.76) and 100 ms (26 %, p = 0.452, d = 0.68).The motor time was 30 % slower for gluteus maximus, 42 % slower for rectus femoris and 50 % slower for biceps femoris in the elderly than in the young. Impaired capacity of the elderly, especially fallers, may be explained by neural and morphological aspects of the muscles. The process of senescence affects the muscle function of the hip flexion and extension, and falls may be related to lower rate of torque development and slower motor time of biceps femoris.

BDNF-TrkB Signaling Coupled to nPKCε and cPKCβI Modulate the Phosphorylation of the Exocytotic Protein Munc18-1 During Synaptic Activity at the Neuromuscular Junction.

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Simó, Anna; Just-Borràs, Laia; Cilleros-Mañé, Víctor; Hurtado, Erica; Nadal, Laura; Tomàs, Marta; Garcia, Neus; Lanuza, Maria A; Tomàs, Josep

2018-01-01

Munc18-1, a neuron-specific member of the Sec1/Munc18 family, is involved in neurotransmitter release by binding tightly to syntaxin. Munc18-1 is phosphorylated by PKC on Ser-306 and Ser-313 in vitro which reduces the amount of Munc18-1 able to bind syntaxin. We have previously identified that PKC is involved in neurotransmitter release when continuous electrical stimulation imposes a moderate activity on the NMJ and that muscle contraction through TrkB has an important impact on presynaptic PKC isoforms levels, specifically cPKCβI and nPKCε. Therefore, the present study was designed to understand how Munc18-1 phosphorylation is affected by (1) synaptic activity at the neuromuscular junction, (2) nPKCε and cPKCβI isoforms activity, (3) muscle contraction per se , and (4) the BDNF/TrkB signaling in a neuromuscular activity-dependent manner. We performed immunohistochemistry and confocal techniques to evidence the presynaptic location of Munc18-1 in the rat diaphragm muscle. To study synaptic activity, we stimulated the phrenic nerve (1 Hz, 30 min) with or without contraction (abolished by μ-conotoxin GIIIB). Specific inhibitory reagents were used to block nPKCε and cPKCβI activity and to modulate the tropomyosin receptor kinase B (TrkB). Main results obtained from Western blot experiments showed that phosphorylation of Munc18-1 at Ser-313 increases in response to a signaling mechanism initiated by synaptic activity and directly mediated by nPKCε. Otherwise, cPKCβI and TrkB activities work together to prevent this synaptic activity-induced Munc18-1 phosphorylation by a negative regulation of cPKCβI over nPKCε. Therefore, a balance between the activities of these PKC isoforms could be a relevant cue in the regulation of the exocytotic apparatus. The results also demonstrate that muscle contraction prevents the synaptic activity-induced Munc18-1 phosphorylation through a mechanism that opposes the TrkB/cPKCβI/nPKCε signaling.

The Effect of Proprioceptive Neuromuscular Facilitation on Learning Fine Motor Skills: A Preliminary Study

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Mohammad Reza Shahabi Kaseb

2016-09-01

Full Text Available Introduction: Preparation of neuromuscular system prior to performing motor skills affects the learning of motor skills. The present study was conducted to investigate the effects of Proprioceptive Neuromuscular Facilitation (PNF on limb coordination and accuracy in dart throwing skill. Methods: Thirty two male students were randomly selected as study sample. Based on the pretest scores, the participants were divided into three groups: experimental (proprioceptive neuromuscular facilitation, first control (without warm-up, and second control (specific warm-up. During the acquisition phase, the participants first performed the preparation training related to their own group, then all groups performed the exercise program of dart throwing consisting of 6 blocks of 9 trials in 4 training sessions. Finally, 20 days following the last exercise session, the subjects took the retention and transfer tests. Results: The results of one-way ANOVA test for coordination variable in acquisition test showed no significant difference between the groups, while there was a statistically significant difference between groups regarding coordination variable in retention and transfer tests. Furthermore, the results of one-way ANOVA for the accuracy variable in acquisition and retention tests showed no statistically significant difference between the three groups, while there was a statistically significant difference between groups for accuracy variable in transfer test. Conclusion: It seems that proprioceptive neuromuscular facilitation, as a preparation method before performance, can enhance the efficacy of training to better learn the coordination pattern of fine motor skills.

Running Economy: Neuromuscular and Joint Stiffness Contributions in Trained Runners.

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Tam, Nicholas; Tucker, Ross; Santos-Concejero, Jordan; Prins, Danielle; Lamberts, Robert P

2018-05-29

It is debated whether running biomechanics make good predictors of running economy, with little known information about the neuromuscular and joint stiffness contributions to economical running gait. The aim of this study was to understand the relationship between certain neuromuscular and spatiotemporal biomechanical factors associated with running economy. Thirty trained runners performed a 6-minute constant-speed running set at 3.3 m∙s -1 , where oxygen consumption was assessed. Overground running trials were also performed at 3.3 m∙s -1 to assess kinematics, kinetics and muscle activity. Spatiotemporal gait variables, joint stiffness, pre-activation and stance phase muscle activity (gluteus medius; rectus femoris (RF); biceps femoris(BF); peroneus longus (PL); tibialis anterior (TA); gastrocnemius lateralis and medius (LG and MG) were variables of specific interest and thus determined. Additionally, pre-activation and ground contact of agonist:antagonist co-activation were calculated. More economical runners presented with short ground contact times (r=0.639, p<0.001) and greater strides frequencies (r=-0.630, p<0.001). Lower ankle and greater knee stiffness were associated with lower oxygen consumption (r=0.527, p=0.007 & r=0.384, p=0.043, respectively). Only LG:TA co-activation during stance were associated with lower oxygen cost of transport (r=0.672, p<0.0001). Greater muscle pre-activation and bi-articular muscle activity during stance were associated with more economical runners. Consequently, trained runners who exhibit greater neuromuscular activation prior to and during ground contact, in turn optimise spatiotemporal variables and joint stiffness, will be the most economical runners.

Neuromodulation of activity-dependent synaptic enhancement at crayfish neuromuscular junction.

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Qian, S M; Delaney, K R

1997-10-17

Action potential-evoked transmitter release is enhanced for many seconds after moderate-frequency stimulation (e.g. 15 Hz for 30 s) at the excitor motorneuron synapse of the crayfish dactyl opener muscle. Beginning about 1.5 s after a train, activity-dependent synaptic enhancement (ADSE) is dominated by a process termed augmentation (G.D. Bittner, D.A. Baxter, Synaptic plasticity at crayfish neuromuscular junctions: facilitation and augmentation, Synapse 7 (1991) 235-243'[4]; K.L. Magleby, Short-term changes in synaptic efficacy, in: G.M. Edelman, L.E. Gall, C.W. Maxwell (Eds.), Synaptic Function, John Wiley and Sons, New York, 1987, pp. 21-56; K.L. Magleby; J.E. Zengel, Augmentation: a process that acts to increase transmitter release at the frog neuromuscular junction, J. Physiol. (Lond.) 257 (1976) 449-470) which decays approximately exponentially with a time constant of about 10 s at 16 degrees C, reflecting the removal of Ca2+ which accumulates during the train in presynaptic terminals (K.R. Delaney, D.W. Tank, R.S. Zucker, Serotonin-mediated enhancement of transmission at crayfish neuromuscular junction is independent of changes in calcium, J. Neurosci. 11 (1991) 2631-2643). Serotonin (5-HT, 1 microM) increases evoked and spontaneous transmitter release several-fold (D. Dixon, H.L. Atwood, Crayfish motor nerve terminal's response to serotonin examined by intracellular microelectrode, J. Neurobiol. 16 (1985) 409-424; J. Dudel, Modulation of quantal synaptic release by serotonin and forskolin in crayfish motor nerve terminals, in: Modulation of Synaptic Transmission and Plasticity in Nervous Systems, G. Hertting, H.-C. Spatz (Eds.), Springer-Verlag, Berlin, 1988; S. Glusman, E.A. Kravitz. The action of serotonin on excitatory nerve terminals in lobster nerve-muscle preparations, J. Physiol. (Lond.) 325 (1982) 223-241). We found that ADSE persists about 2-3 times longer after moderate-frequency presynaptic stimulation in the presence of 5-HT. This slowing of the

Muscle size, neuromuscular activation, and rapid force characteristics in elderly men and women

DEFF Research Database (Denmark)

Suetta, C; Aagaard, P; Magnusson, S P

2007-01-01

quadriceps muscle cross-sectional area (LCSA), contractile rate of force development (RFD, Delta force/Delta time), impulse (integral force dt), muscle activation deficit (interpolated twitch technique), maximal neuromuscular activity [electromyogram (EMG)], and antagonist muscle coactivation in elderly men......%), contractile RFD (W: 17-26%; M: 15-24%), impulse (W: 10-19%, M: 19-20%), maximal EMG amplitude (W: 22-25%, M: 22-28%), and an increased muscle activation deficit (-18%) compared with UN. Furthermore, women were less strong (AF: 40%; UN: 39%), had less muscle mass (AF: 33%; UN: 34%), and had a lower RFD (AF: 38......-50%; UN: 41-48%) compared with men. Similarly, maximum EMG amplitude was smaller for both agonists (AF: 51-63%; UN: 35-61%) and antagonist (AF: 49-64%; UN: 36-56%) muscles in women compared with men. However, when MVC and RFD were normalized to LCSA, there were no differences between genders. The present...

Neuromuscular Monitoring, Muscle Relaxant Use, and Reversal at a Tertiary Teaching Hospital 2.5 Years after Introduction of Sugammadex: Changes in Opinions and Clinical Practice

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Thomas Ledowski

2015-01-01

Full Text Available Sugammadex was introduced to Royal Perth Hospital in early 2011 without access restriction. Two departmental audits (26-page online survey and 1-week in-theatre snapshot audit were undertaken to investigate the change of beliefs and clinical practice related to the use of neuromuscular blocking agents at the Royal Perth Hospital since this introduction. Results were compared with data from 2011. We found that, in the 2.5 years since introduction of Sugammadex, more anesthetists (69.5 versus 38% utilized neuromuscular monitoring, and aminosteroidal neuromuscular blocking agents were used in 94.3% of cases (versus 77% in 2011. Furthermore, 53% of anesthetists identified with a practice of “deeper and longer” intraoperative paralysis of patients. All 71 patients observed during the 5-day in-theatre audit were reversed with Sugammadex. Since the introduction of Sugammadex, 69% (n=20 of respondents felt it provided “faster turnover,” less postoperative residual neuromuscular blockade (n=23; 79%, and higher anesthetist satisfaction (n=17; 59%. 45% (n=13 of colleagues reported that they would feel professionally impaired without the unrestricted availability of Sugammadex, and 1 colleague would refuse to work in a hospital without this drug being freely available. In clinical practice Sugammadex was frequently (57% mildly overdosed, with 200 mg being the most commonly administered dose.

Sugammadex compared with neostigmine/glycopyrrolate for routine reversal of neuromuscular block: a systematic review and economic evaluation†

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Paton, F.; Paulden, M.; Chambers, D.; Heirs, M.; Duffy, S.; Hunter, J. M.; Sculpher, M.; Woolacott, N.

2010-01-01

Summary The cost-effectiveness of sugammadex for the routine reversal of muscle relaxation produced by rocuronium or vecuronium in UK practice is uncertain. We performed a systematic review of randomized controlled trials of sugammadex compared with neostigmine/glycopyrrolate and an economic assessment of sugammadex for the reversal of moderate or profound neuromuscular block (NMB) produced by rocuronium or vecuronium. The economic assessment aimed to establish the reduction in recovery time and the ‘value of time saved’ which would be necessary for sugammadex to be potentially cost-effective compared with existing practice. Three trials indicated that sugammadex 2 mg kg−1 (4 mg kg−1) produces more rapid recovery from moderate (profound) NMB than neostigmine/glycopyrrolate. The economic assessment indicated that if the reductions in recovery time associated with sugammadex in the trials are replicated in routine practice, sugammadex would be cost-effective if those reductions are achieved in the operating theatre (assumed value of staff time, £4.44 per minute), but not if they are achieved in the recovery room (assumed value of staff time, £0.33 per minute). However, there is considerable uncertainty in these results. Sugammadex has the potential to be cost-effective compared with neostigmine/glycopyrrolate for the reversal of rocuronium-induced moderate or profound NMB, provided that the time savings observed in trials can be achieved and put to productive use in clinical practice. Further research is required to evaluate the effects of sugammadex on patient safety, predictability of recovery from NMB, patient outcomes, and efficient use of resources. PMID:20935005

BDNF-TrkB Signaling Coupled to nPKCε and cPKCβI Modulate the Phosphorylation of the Exocytotic Protein Munc18-1 During Synaptic Activity at the Neuromuscular Junction

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Anna Simó

2018-06-01

Full Text Available Munc18-1, a neuron-specific member of the Sec1/Munc18 family, is involved in neurotransmitter release by binding tightly to syntaxin. Munc18-1 is phosphorylated by PKC on Ser-306 and Ser-313 in vitro which reduces the amount of Munc18-1 able to bind syntaxin. We have previously identified that PKC is involved in neurotransmitter release when continuous electrical stimulation imposes a moderate activity on the NMJ and that muscle contraction through TrkB has an important impact on presynaptic PKC isoforms levels, specifically cPKCβI and nPKCε. Therefore, the present study was designed to understand how Munc18-1 phosphorylation is affected by (1 synaptic activity at the neuromuscular junction, (2 nPKCε and cPKCβI isoforms activity, (3 muscle contraction per se, and (4 the BDNF/TrkB signaling in a neuromuscular activity-dependent manner. We performed immunohistochemistry and confocal techniques to evidence the presynaptic location of Munc18-1 in the rat diaphragm muscle. To study synaptic activity, we stimulated the phrenic nerve (1 Hz, 30 min with or without contraction (abolished by μ-conotoxin GIIIB. Specific inhibitory reagents were used to block nPKCε and cPKCβI activity and to modulate the tropomyosin receptor kinase B (TrkB. Main results obtained from Western blot experiments showed that phosphorylation of Munc18-1 at Ser-313 increases in response to a signaling mechanism initiated by synaptic activity and directly mediated by nPKCε. Otherwise, cPKCβI and TrkB activities work together to prevent this synaptic activity–induced Munc18-1 phosphorylation by a negative regulation of cPKCβI over nPKCε. Therefore, a balance between the activities of these PKC isoforms could be a relevant cue in the regulation of the exocytotic apparatus. The results also demonstrate that muscle contraction prevents the synaptic activity–induced Munc18-1 phosphorylation through a mechanism that opposes the TrkB/cPKCβI/nPKCε signaling.

Vellozia flavicans Mart. ex Schult. hydroalcoholic extract inhibits the neuromuscular blockade induced by Bothrops jararacussu venom.

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Tribuiani, Natália; da Silva, Alexandro Mateus; Ferraz, Miriéle Cristina; Silva, Magali Glauzer; Bentes, Ana Paula Guerreiro; Graziano, Talita Signoreti; dos Santos, Marcio Galdino; Cogo, José Carlos; Varanda, Eliana Aparecida; Groppo, Francisco Carlos; Cogo, Karina; Oshima-Franco, Yoko

2014-02-08

Snakebite is a significant public health issue in tropical countries. In Brazil, some of the most common snake envenomations are from Bothrops. Bothrops bites trigger local and systemic effects including edema, pain, erythema, cyanosis, infections, and necrosis. Vellozia flavicans is a plant from the Brazilian "cerrado" (savanna) that is popularly used as an anti-inflammatory medicine. Since inflammation develops quickly after Bothrops bites, which can lead to infection, the aim of the present study was to observe possible anti-snake venom and antimicrobial activities of V. flavicans (Vf). The chromatographic profile of the main constituents from the Vf leaf hydroalcoholic extract was obtained by thin-layer chromatography (TLC). The anti-snake venom activity was measured by Vf's ability to neutralize the in vitro neuromuscular blockade caused by Bothrops jararacussu venom (Bjssu) in a mouse phrenic nerve-diaphragm model (PND). After a 20 min incubation, preparations of PND were added to Tyrode's solution (control); Vf (0.2, 0.5, 1, and 2 mg/mL); 40 μg/mL Bjssu; pre-incubation for 30 min with Bjssu and 1 mg/mL Vf; and a Bjssu pretreated preparation (for 10 min) followed by 1 mg/mL Vf. Myographic recording was performed, and the contractile responses were recorded. The antimicrobial activity (minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC]) was obtained for Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis, using gentamicin and vancomycin as positive controls. TLC analysis yielded several compounds from Vf, such as flavonoids (quercetin) and phenolic acids (chlorogenic acid). Bjssu completely blocked the contractile responses of PND preparations, while Vf preserved 97% (±10%) of the contractile responses when incubated with Bjssu. In the PND pretreated with Bjssu, Vf was able to inhibit the neuromuscular blockade progress. MIC and MBC of Vf ranged from 2.5 to 5.0 mg/mL for P. aeruginosa

Efficacy and safety of sugammadex versus neostigmine in reversing neuromuscular blockade in adults.

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Hristovska, Ana-Marija; Duch, Patricia; Allingstrup, Mikkel; Afshari, Arash

2017-08-14

Acetylcholinesterase inhibitors, such as neostigmine, have traditionally been used for reversal of non-depolarizing neuromuscular blocking agents. However, these drugs have significant limitations, such as indirect mechanisms of reversal, limited and unpredictable efficacy, and undesirable autonomic responses. Sugammadex is a selective relaxant-binding agent specifically developed for rapid reversal of non-depolarizing neuromuscular blockade induced by rocuronium. Its potential clinical benefits include fast and predictable reversal of any degree of block, increased patient safety, reduced incidence of residual block on recovery, and more efficient use of healthcare resources. The main objective of this review was to compare the efficacy and safety of sugammadex versus neostigmine in reversing neuromuscular blockade caused by non-depolarizing neuromuscular agents in adults. We searched the following databases on 2 May 2016: Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE (WebSPIRS Ovid SP), Embase (WebSPIRS Ovid SP), and the clinical trials registries www.controlled-trials.com, clinicaltrials.gov, and www.centerwatch.com. We re-ran the search on 10 May 2017. We included randomized controlled trials (RCTs) irrespective of publication status, date of publication, blinding status, outcomes published, or language. We included adults, classified as American Society of Anesthesiologists (ASA) I to IV, who received non-depolarizing neuromuscular blocking agents for an elective in-patient or day-case surgical procedure. We included all trials comparing sugammadex versus neostigmine that reported recovery times or adverse events. We included any dose of sugammadex and neostigmine and any time point of study drug administration. Two review authors independently screened titles and abstracts to identify trials for eligibility, examined articles for eligibility, abstracted data, assessed the articles, and excluded obviously irrelevant reports. We resolved

The novel protein kinase C epsilon isoform at the adult neuromuscular synapse: location, regulation by synaptic activity-dependent muscle contraction through TrkB signaling and coupling to ACh release.

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Obis, Teresa; Besalduch, Núria; Hurtado, Erica; Nadal, Laura; Santafe, Manel M; Garcia, Neus; Tomàs, Marta; Priego, Mercedes; Lanuza, Maria A; Tomàs, Josep

2015-02-10

Protein kinase C (PKC) regulates a variety of neural functions, including neurotransmitter release. Although various PKC isoforms can be expressed at the synaptic sites and specific cell distribution may contribute to their functional diversity, little is known about the isoform-specific functions of PKCs in neuromuscular synapse. The present study is designed to examine the location of the novel isoform nPKCε at the neuromuscular junction (NMJ), their synaptic activity-related expression changes, its regulation by muscle contraction, and their possible involvement in acetylcholine release. We use immunohistochemistry and confocal microscopy to demonstrate that the novel isoform nPKCε is exclusively located in the motor nerve terminals of the adult rat NMJ. We also report that electrical stimulation of synaptic inputs to the skeletal muscle significantly increased the amount of nPKCε isoform as well as its phosphorylated form in the synaptic membrane, and muscle contraction is necessary for these nPKCε expression changes. The results also demonstrate that synaptic activity-induced muscle contraction promotes changes in presynaptic nPKCε through the brain-derived neurotrophic factor (BDNF)-mediated tyrosine kinase receptor B (TrkB) signaling. Moreover, nPKCε activity results in phosphorylation of the substrate MARCKS involved in actin cytoskeleton remodeling and related with neurotransmission. Finally, blocking nPKCε with a nPKCε-specific translocation inhibitor peptide (εV1-2) strongly reduces phorbol ester-induced ACh release potentiation, which further indicates that nPKCε is involved in neurotransmission. Together, these results provide a mechanistic insight into how synaptic activity-induced muscle contraction could regulate the presynaptic action of the nPKCε isoform and suggest that muscle contraction is an important regulatory step in TrkB signaling at the NMJ.

Acute fatigue-induced changes in muscle mechanical properties and neuromuscular activity in elite handball players following a handball match

DEFF Research Database (Denmark)

Thorlund, Jonas Bloch; Michalsik, L B; Madsen, Klavs

2008-01-01

The purpose of the present study was to determine the acute fatigue development in muscle mechanical properties and neuromuscular activity in response to handball match play. Male elite handball players (n = 10) were tested before and after a simulated handball match for maximal isometric strength...... work (6.8%, P handball match play, which...

Adjustments with running speed reveal neuromuscular adaptations during landing associated with high mileage running training.

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Verheul, Jasper; Clansey, Adam C; Lake, Mark J

2017-03-01

It remains to be determined whether running training influences the amplitude of lower limb muscle activations before and during the first half of stance and whether such changes are associated with joint stiffness regulation and usage of stored energy from tendons. Therefore, the aim of this study was to investigate neuromuscular and movement adaptations before and during landing in response to running training across a range of speeds. Two groups of high mileage (HM; >45 km/wk, n = 13) and low mileage (LM; joint stiffness might predominantly be governed by tendon stiffness rather than muscular activations before landing. Estimated elastic work about the ankle was found to be higher in the HM runners, which might play a role in reducing weight acceptance phase muscle activation levels and improve muscle activation efficiency with running training. NEW & NOTEWORTHY Although neuromuscular factors play a key role during running, the influence of high mileage training on neuromuscular function has been poorly studied, especially in relation to running speed. This study is the first to demonstrate changes in neuromuscular conditioning with high mileage training, mainly characterized by lower thigh muscle activation after touch down, higher initial knee stiffness, and greater estimates of energy return, with adaptations being increasingly evident at faster running speeds. Copyright © 2017 the American Physiological Society.

Neuromuscular Disorders

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... lead to twitching, cramps, aches and pains, and joint and movement problems. Sometimes it also affects heart function and your ability to breathe. Examples of neuromuscular disorders include Amyotrophic lateral sclerosis Multiple sclerosis Myasthenia ...

Comparison in lower leg neuromuscular activity between runners with unilateral mid-portion Achilles tendinopathy and healthy individuals.

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Baur, Heiner; Müller, Steffen; Hirschmüller, Anja; Cassel, Michael; Weber, Josefine; Mayer, Frank

2011-06-01

Neuromuscular control in functional situations and possible impairments due to Achilles tendinopathy are not well understood. Thirty controls (CO) and 30 runners with Achilles tendinopathy (AT) were tested on a treadmill at 3.33 ms(-1) (12 km h(-1)). Neuromuscular activity of the lower leg (tibialis anterior, peroneal, and gastrocnemius muscle) was measured by surface electromyography. Mean amplitude values (MAV) for the gait cycle phases preactivation, weight acceptance and push-off were calculated and normalised to the mean activity of the entire gait cycle. MAVs of the tibialis anterior did not differ between CO and AT in any gait cycle phase. The activation of the peroneal muscle was lower in AT in weight acceptance (p=0.006), whereas no difference between CO and AT was found in preactivation (p=0.71) and push-off (p=0.83). Also, MAVs of the gastrocnemius muscle did not differ between AT and CO in preactivity (p=0.71) but were reduced in AT during weight acceptance (p=0.001) and push-off (p=0.04). Achilles tendinopathy does not seem to alter pre-programmed neural control but might induce mechanical deficits of the lower extremity during weight bearing (joint stability). This should be addressed in the therapy process of AT. Copyright © 2010 Elsevier Ltd. All rights reserved.

Comparison of pancuronium and vecuronium for fetal neuromuscular blockade during invasive procedures.

Science.gov (United States)

Watson, W J; Atchison, S R; Harlass, F E

1996-01-01

Neuromuscular blocking agents, used to arrest fetal motion for invasive intrauterine procedures, may cause temporary fetal heart rate changes. After 21 invasive procedures using either pancuronium bromide or vecuronium bromide, post-procedure fetal heart rate tracings were retrospectively compared. Pancuronium was associated with an increased fetal heart rate and decreased beat-to-beat variability for 2.5 hours after its use, whereas vecuronium caused no fetal heart rate changes. Vecuronium bromide offers advantages over pancuronium, because the decreased effect on the fetal heart allows better assessment of fetal well-being immediately following invasive intrauterine procedures.

Síndrome de Tako-Tsubo em decorrência de bloqueio neuromuscular residual: relato de caso Síndrome de Tako-Tsubo como consecuencia de bloqueo neuromuscular residual: relato de caso Tako-Tsubo syndrome secondary to residual neuromuscular blockade: case report

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Marcos Guilherme Cunha Cruvinel

2008-12-01

neuromuscular residual. RELATO DEL CASO: Paciente del sexo femenino, 61 años, estado físico ASA I, sometida a la anestesia general asociada al bloqueo paravertebral cervical para la reparación artroscópica de lesión de manguito de los rotadores. Después de la extubación, quedó demostrado el bloqueo neuromuscular residual a través del examen clínico. En la sala de recuperación postanestésica, evolucionó con somnolencia, taquicardia, hipertensión arterial y acidosis respiratoria grave. Después de la reintubación evolucionó con parada cardíaca en actividad eléctrica sin pulso, revertida con adrenalina y masaje cardíaco externo. En el postoperatorio presentó una elevación de segmento ST, aumento de troponina y acinesia de segmento medio-apical del ventrículo izquierdo, con fracción de eyección estimada en un 30%. La cineangiocoronariografía mostró coronarias exentas de ateromatosis significativa y un grave comprometimiento de la función sistólica con acinesia inferior y ántero-septo-apical, con hipercontratilidad compensatoria de sus porciones basales. Con el tratamiento iniciado, hubo una recuperación funcional completa. CONCLUSIONES: El bloqueo neuromuscular residual asociado a la parálisis diafragmática y la posible atelectasia pulmonar, que conlleva a la insuficiencia respiratoria, hipercapnia y descarga adrenérgica, fueron los factores desencadenantes del síndrome de Tako-Tsubo con su grave repercusión clínica.BACKGROUND AND OBJECTIVES: Tako-Tsubo syndrome is a rare postoperative complication with a 5% mortality rate. The objective of this report was to present residual neuromuscular blockade as a trigger for this syndrome, discuss this disorder, and call attention to the risks of residual neuromuscular blockade. CASE REPORT: A 61-year old female, physical status ASA I, who underwent general anesthesia associated with paravertebral cervical block for arthroscopic repair of a rotator cuff lesion. Physical exam after extubation detected

Immediate effect of selective neuromuscular electrical stimulation on the electromyographic activity of the vastus medialis oblique muscle

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Denise DalAva Augusto

2008-07-01

Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n2p155 The Patellofemoral pain syndrome (PFPS is described as an anterior or retropatellar knee pain in the absence of other associated diseases, and has often been associated with dysfunction of the vastus medialis oblique muscle (VMO. However, several studies have demonstrated the impossibility of selectively activating this muscle with exercises. The aim of the present study was to analyze the immediate effect of neuromuscular electrical stimulation of VMO muscle by means of monitoring the electromyographic activity of the vastus medialis oblique (VMO and vastus lateralis (VL muscles. Eighteen healthy women with a mean age of 23.2 years and mean BMI of 20 Kg/m2 were evaluated. The study protocol included electromyographic analysis of VMO and VL muscles, before and immediately after neuromuscular electrical stimulation of the VMO muscle. During the electromyographic analysis, the volunteers performed maximal voluntary isometric contraction in a 60° knee extension on an isokinetic dynamometer. “Russian current” apparatus was used for electrical stimulation. Results: The data analysis demonstrated a signifi cant increase in VMO activation intensity immediately after it had been electrically stimulated (p=0.0125, whereas VL activation intensity exhibited no signifi cant increase (p=0.924. Moreover, a significant increase in the VMO/VL ratio was also detected (p=0.048. In this study it was observed that electrical stimulation modifiedthe VMO/VL ratio, which suggests electrical stimulation has a benefi cial effect on VMO muscle strength.

Kinship and interaction in neuromuscular pharmacology

NARCIS (Netherlands)

Schiere, Sjouke

2006-01-01

The background of this thesis is presented in the introductory chapters and stafts with a brief history of neuromuscular relaxants. It is followed by a short description of the neuromuscular physiology and pharmacology in chapters 2 and 3, respectively. In chapter 4 the aim of the thesis is

Adenosine receptors and muscarinic receptors cooperate in acetylcholine release modulation in the neuromuscular synapse.

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Santafe, M M; Priego, M; Obis, T; Garcia, N; Tomàs, M; Lanuza, M A; Tomàs, J

2015-07-01

Adenosine receptors (ARs) are present in the motor terminals at the mouse neuromuscular junction. ARs and the presynaptic muscarinic acetylcholine receptors (mAChRs) share the functional control of the neuromuscular junction. We analysed their mutual interaction in transmitter release modulation. In electrophysiological experiments with unaltered synaptic transmission (muscles paralysed by blocking the voltage-dependent sodium channel of the muscle cells with μ-conotoxin GIIIB), we found that: (i) a collaborative action between different AR subtypes reduced synaptic depression at a moderate activity level (40 Hz); (ii) at high activity levels (100 Hz), endogenous adenosine production in the synaptic cleft was sufficient to reduce depression through A1 -type receptors (A1 Rs) and A2 A-type receptors (A2 A Rs); (iii) when the non-metabolizable 2-chloroadenosine (CADO) agonist was used, both the quantal content and depression were reduced; (iv) the protective effect of CADO on depression was mediated by A1 Rs, whereas A2 A Rs seemed to modulate A1 Rs; (v) ARs and mAChRs absolutely depended upon each other for the modulation of evoked and spontaneous acetylcholine release in basal conditions and in experimental conditions with CADO stimulation; (vi) the purinergic and muscarinic mechanisms cooperated in the control of depression by sharing a common pathway although the purinergic control was more powerful than the muscarinic control; and (vii) the imbalance of the ARs created by using subtype-selective and non-selective inhibitory and stimulatory agents uncoupled protein kinase C from evoked transmitter release. In summary, ARs (A1 Rs, A2 A Rs) and mAChRs (M1 , M2 ) cooperated in the control of activity-dependent synaptic depression and may share a common protein kinase C pathway. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Sensorimotor control and neuromuscular activity of the shoulder in adolescent competitive swimmers with generalized joint hypermobility

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Frydendal, Thomas; Eshøj, Henrik; Liaghat, Behnam

2018-01-01

INTRODUCTION: Shoulder pain is highly prevalent in competitive swimmers, and generalized joint hypermobility (GJH) is considered a risk factor. Sensorimotor control deficiencies and altered neuromuscular activation of the shoulder may represent underlying factors. RESEARCH QUESTION: To investigate...... whether competitive swimmers with GJH including shoulder hypermobility (GJHS) differ in shoulder sensorimotor control and muscle activity from those without GJH and no shoulder hypermobility (NGJH). METHODS: Competitive swimmers (aged 13-17) were recruited. GJHS or NGJH status was determined using...... (29%) pectoralis major activity during BL-EO compared to NGJH (5.35 ± 1.77%MVE vs. 7.51 ± 1.96%MVE; p = 0.043). SIGNIFICANCE: Adolescent competitive swimmers with GJHS displayed no shoulder sensorimotor control deficiencies and no generally altered shoulder muscle activity pattern, except...

Neuromuscular Control and Coordination during Cycling

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Li, Li

2004-01-01

The neuromuscular control aspect of cycling has been investigated through the effects of modifying posture and cadence. These studies show that changing posture has a more profound influence on neuromuscular coordination than does changing slope. Most of the changes with standing posture occur late in the downstroke: increased ankle and knee joint…

Occlus-o-Guide® versus Andresen activator appliance: neuromuscular evaluation.

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Farronato, Giampietro; Giannini, Lucia; Galbiati, Guido; Grillo, Elena; Maspero, Cinzia

2013-05-20

The aim of the present study was to assess the muscular variations at the electromyography (EMG) level for the anterior temporalis muscles and masseter muscles during treatment with Occlus-o-Guide® and Andresen activator appliances. Eighty-two patients (35 males and 47 females) aged between 8 and 12 years (mean age, 10.5±0.8 years) participated in the study. Fifty patients underwent treatment with an Occlus-o-Guide® and 32 patients with an Andresen activator. All patients underwent EMG examination using a Freely EMG (De Gotzen, Legnano, Italy) and surface bipolar electrodes when the appliances were worn for the first time (T0), and after 6 months (T1) and after 12 months (T2) of appliance use. Statistical analysis showed that both at T0 and T2, the percent overlapping coefficient (POC) of the anterior temporalis muscles was not statistically different between the appliance groups. At T0, the POC of the masseter muscles was significantly lower for the Andresen appliance as compared to the Occlus-o-Guide® (p=0.02), while at T2 this significance was lost. At insertion of an appliance, all patients show neuromuscular balance that does not correspond to orthognathic occlusion. Both appliances work by creating muscular imbalance. With the appliances in situ, EMG responses were generally analogous for the Occlus-o-Guide® and the Andresen activator; however, the imbalance was greater and the recovery of the orthological muscular balance was slower in patients under treatment with the Andresen activator as compared to those with the Occlus-o-Guide®.

Efficacy of brain-computer interface-driven neuromuscular electrical stimulation for chronic paresis after stroke.

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Mukaino, Masahiko; Ono, Takashi; Shindo, Keiichiro; Fujiwara, Toshiyuki; Ota, Tetsuo; Kimura, Akio; Liu, Meigen; Ushiba, Junichi

2014-04-01

Brain computer interface technology is of great interest to researchers as a potential therapeutic measure for people with severe neurological disorders. The aim of this study was to examine the efficacy of brain computer interface, by comparing conventional neuromuscular electrical stimulation and brain computer interface-driven neuromuscular electrical stimulation, using an A-B-A-B withdrawal single-subject design. A 38-year-old male with severe hemiplegia due to a putaminal haemorrhage participated in this study. The design involved 2 epochs. In epoch A, the patient attempted to open his fingers during the application of neuromuscular electrical stimulation, irrespective of his actual brain activity. In epoch B, neuromuscular electrical stimulation was applied only when a significant motor-related cortical potential was observed in the electroencephalogram. The subject initially showed diffuse functional magnetic resonance imaging activation and small electro-encephalogram responses while attempting finger movement. Epoch A was associated with few neurological or clinical signs of improvement. Epoch B, with a brain computer interface, was associated with marked lateralization of electroencephalogram (EEG) and blood oxygenation level dependent responses. Voluntary electromyogram (EMG) activity, with significant EEG-EMG coherence, was also prompted. Clinical improvement in upper-extremity function and muscle tone was observed. These results indicate that self-directed training with a brain computer interface may induce activity- dependent cortical plasticity and promote functional recovery. This preliminary clinical investigation encourages further research using a controlled design.

Neuromuscular complications of immune checkpoint inhibitor therapy.

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Kolb, Noah A; Trevino, Christopher R; Waheed, Waqar; Sobhani, Fatemeh; Landry, Kara K; Thomas, Alissa A; Hehir, Mike

2018-01-17

Immune checkpoint inhibitor (ICPI) therapy unleashes the body's natural immune system to fight cancer. ICPIs improve overall cancer survival, however, the unbridling of the immune system may induce a variety of immune-related adverse events. Neuromuscular immune complications are rare but they can be severe. Myasthenia gravis and inflammatory neuropathy are the most common neuromuscular adverse events but a variety of others including inflammatory myopathy are reported. The pathophysiologic mechanism of these autoimmune disorders may differ from that of non-ICPI-related immune diseases. Accordingly, while the optimal treatment for ICPI-related neuromuscular disorders generally follows a traditional paradigm, there are important novel considerations in selecting appropriate immunosuppressive therapy. This review presents 2 new cases, a summary of neuromuscular ICPI complications, and an approach to the diagnosis and treatment of these disorders. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

Neuromuscular Responses of Elite Skaters During Different Roller Figure Skating Jumps

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Pantoja Patrícia Dias

2014-07-01

Full Text Available This study aimed to describe the neuromuscular activity of elite athletes who performed various roller figure skating jumps, to determine whether the muscle activation is greater during jumps with more rotations and in which phase the muscles are more active. This study also aimed to analyze if there is any difference in the muscle activity pattern between female and male skaters. Four elite skaters were evaluated, and each participated in two experimental sessions. During the first session, anthropometric data were collected, and the consent forms were signed. For the second session, neuromuscular data were collected during jumps, which were performed with skates at a rink. The following four roller figure skating jumps were evaluated: single Axel, double Axel, double Mapes and triple Mapes. The neuromuscular activity of the following seven muscles was obtained with an electromyograph which was fixed to the waist of each skater with a strap: biceps femoris, lateral gastrocnemius, tibialis anterior, rectus femoris, vastus lateralis, vastus medialis and gluteus maximus. The signal was transmitted wirelessly to a laptop. During the roller figure skating jumps, the lateral gastrocnemius, rectus femoris, vastus lateralis, biceps femoris and gluteus maximus, showed more activation during the jumps with more rotations, and the activation mainly occurred during the propulsion and flight phases. Female skaters demonstrated higher muscle activities in tibialis anterior, vastus lateralis, vastus medialis and gluteus maximus during the landing phase of the triple Mapes, when compared to their male counterparts. The results obtained in this study should be considered when planning training programs with specific exercises that closely resemble the roller figure skating jumps. This may be important for the success of elite skaters in competitions.

Neuromuscular Responses of Elite Skaters During Different Roller Figure Skating Jumps

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Pantoja, Patrícia Dias; Mello, André; Liedtke, Giane Veiga; Kanitz, Ana Carolina; Cadore, Eduardo Lusa; Pinto, Stephanie Santana; Alberton, Cristine Lima; Kruel, Luiz Fernando Martins

2014-01-01

This study aimed to describe the neuromuscular activity of elite athletes who performed various roller figure skating jumps, to determine whether the muscle activation is greater during jumps with more rotations and in which phase the muscles are more active. This study also aimed to analyze if there is any difference in the muscle activity pattern between female and male skaters. Four elite skaters were evaluated, and each participated in two experimental sessions. During the first session, anthropometric data were collected, and the consent forms were signed. For the second session, neuromuscular data were collected during jumps, which were performed with skates at a rink. The following four roller figure skating jumps were evaluated: single Axel, double Axel, double Mapes and triple Mapes. The neuromuscular activity of the following seven muscles was obtained with an electromyograph which was fixed to the waist of each skater with a strap: biceps femoris, lateral gastrocnemius, tibialis anterior, rectus femoris, vastus lateralis, vastus medialis and gluteus maximus. The signal was transmitted wirelessly to a laptop. During the roller figure skating jumps, the lateral gastrocnemius, rectus femoris, vastus lateralis, biceps femoris and gluteus maximus, showed more activation during the jumps with more rotations, and the activation mainly occurred during the propulsion and flight phases. Female skaters demonstrated higher muscle activities in tibialis anterior, vastus lateralis, vastus medialis and gluteus maximus during the landing phase of the triple Mapes, when compared to their male counterparts. The results obtained in this study should be considered when planning training programs with specific exercises that closely resemble the roller figure skating jumps. This may be important for the success of elite skaters in competitions. PMID:25114728

New techniques in the tissue diagnosis of gastrointestinal neuromuscular diseases

Institute of Scientific and Technical Information of China (English)

Charles H Knowles; Joanne E Martin

2009-01-01

Gastrointestinal neuromuscular diseases are a clinically heterogeneous group of disorders of children and adults in which symptoms are presumed or proven to arise as a result of neuromuscular (including interstitial cell of Cajal) dysfunction. Common to most of these diseases are symptoms of impaired motor activity which manifest as slowed or obstructed transit with or without evidence of transient or persistent radiological visceral dilatation. A variety of histopathological techniques and allied investigations are being increasingly applied to tissue biopsies from such patients. This review outlines some of the more recent advances in this field, particularly in the most contentious area of small bowel disease manifesting as intestinal pseudo-obstruction.

Effects of intensive physical rehabilitation on neuromuscular adaptations in adults with poststroke hemiparesis

DEFF Research Database (Denmark)

Andersen, Lars L; Zeeman, Peter; Jørgensen, Jørgen R

2011-01-01

consisting of isokinetic muscle strength, neuromuscular activation measured with electromyography (EMG), electrically evoked muscle twitch contractile properties, and gait performance (10-m Walk Test and 6-min Walk Test). After the 12-week conditioning program, knee extensor and flexor strength increased...... the effect of intensive physical rehabilitation on neuromuscular and functional adaptations in outpatients suffering from hemiparesis after stroke. A within-subject repeated-measures design with the paretic leg as the experimental leg and the nonparetic leg as the control leg was used. Eleven outpatients...... observed in the nonparetic control leg. Gait performance increased 52-68%. In conclusion, intensive physical rehabilitation after stroke leads to clinically relevant neuromuscular improvements, leading to increased voluntary strength during a wide range of contraction modes and velocities, and improved...

A systematic review and meta-analysis of lower limb neuromuscular alterations associated with knee osteoarthritis during level walking.

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Mills, Kathryn; Hunt, Michael A; Leigh, Ryan; Ferber, Reed

2013-08-01

Neuromuscular alterations are increasingly reported in individuals with knee osteoarthritis (KOA) during level walking. We aimed to determine which neuromuscular alterations are consistent in KOA individuals and how these may be influenced by osteoarthritis severity, varus alignment and/or joint laxity. Electronic databases were searched up to July 2012. Cross-sectional observational studies comparing lower-limb neuromuscular activity in individuals with KOA, healthy controls or with different KOA cohorts were included. Two reviewers assessed methodological quality. Effect sizes were used to quantify the magnitude of observed differences. Where studies were homogenous, effect sizes were pooled using a fixed-effects model. Fourteen studies examining neuromuscular alterations in indices of co-contraction, muscle amplitude and muscle activity duration were included. Data pooling revealed that moderate KOA individuals exhibit increased co-contraction of lateral knee muscles (ES 0.64 [0.3 to 0.97]) and moderately increased rectus femoris (ES 0.73 [0.23 to 1.22]), vastus lateralis (ES 0.77 [0.27 to 1.27]) and biceps femoris (ES 1.18 [0.67 to 1.7]) mean amplitude. Non-pooled data indicated prolonged activity of these muscles. Increased medial knee neuromuscular activity was prevalent for those exhibiting varus alignment and medial knee joint laxity. Interpretation Individuals with KOA exhibited increased co-contraction, amplitude and duration of lateral knee muscles regardless of disease severity, limb alignment or medial joint laxity. Individuals with severe disease, varus alignment and medial joint laxity demonstrate up-regulation of medial knee muscles. Future research investigating the efficacy of neuromuscular rehabilitation programs should consider the effect of simultaneous up-regulation of medial and lateral knee muscles on disease progression. © 2013.

Time course of action of sugammadex (Org 25969) on rocuronium-induced block in the Rhesus monkey, using a simple model of equilibration of complex formation.

NARCIS (Netherlands)

Boer, H.D. de; Egmond, J. van; Pol, F. van de; Bom, A.; Driessen, J.J.; Booij, L.H.D.J.

2006-01-01

BACKGROUND: Reversal of neuromuscular block can be accomplished by chemical encapsulation of rocuronium by sugammadex (Org 25969), a synthetic gamma-cyclodextrin derivative. The present study determined the time course of the reversal action of sugammadex on rocuronium-induced block in the

Interaction between protein kinase C and protein kinase A can modulate transmitter release at the rat neuromuscular synapse.

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Santafé, M M; Garcia, N; Lanuza, M A; Tomàs, M; Tomàs, J

2009-02-15

We used intracellular recording to investigate the functional interaction between protein kinase C (PKC) and protein kinase A (PKA) signal transduction cascades in the control of transmitter release in the neuromuscular synapses from adult rats. Our results indicate that: 1) PKA and PKC are independently involved in asynchronous release. 2) Evoked acetylcholine (ACh) release is enhanced with the PKA agonist Sp-8-BrcAMP and the PKC agonist phorbol ester (PMA). 3) PKA has a constitutive role in promoting a component of normal evoked transmitter release because, when the kinase is inhibited with H-89, the release diminishes. However, the PKC inhibitor calphostin C (CaC) does not affect ACh release. 4) PKA regulates neurotransmission without PKC involvement because, after PMA or CaC modulation of the PKC activity, coupling to the ACh release of PKA can normally be stimulated with Sp-8-BrcAMP or inhibited with H-89. 5) After PKA inhibition with H-89, PKC stimulation with PMA (or inhibition with CaC) does not lead to any change in evoked ACh release. However, in PKA-stimulated preparations with Sp-8-BrcAMP, PKC becomes tonically active, thus potentiating a component of release that can now be blocked with CaC. In normal conditions, therefore, PKA was able to modulate ACh release independently of PKC activity, whereas PKA stimulation caused the PKC coupling to evoked release. In contrast, PKA inhibition prevent PKC stimulation (with the phorbol ester) and coupling to ACh output. There was therefore some dependence of PKC on PKA activity in the fine control of the neuromuscular synaptic functionalism and ACh release.

Antibiotic-induced immediate type hypersensitivity is a risk factor for positive allergy skin tests for neuromuscular blocking agents.

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Hagau, Natalia; Gherman, Nadia; Cocis, Mihaela; Petrisor, Cristina

2016-01-01

Skin tests for neuromuscular blocking agents (NMBAs) are not currently recommended for the general population undergoing general anaesthesia. In a previous study we have reported a high incidence of positive allergy tests for NMBAs in patients with a positive history of non-anaesthetic drug allergy, a larger prospective study being needed to confirm those preliminary results. The objective of this study was to compare the skin tests results for patients with a positive history of antibiotic-induced immediate type hypersensitivity reactions to those of controls without drug allergies. Ninety eight patients with previous antibiotic hypersensitivity and 72 controls were prospectively included. Skin tests were performed for atracurium, pancuronium, rocuronium, and suxamethonium. We found 65 positive skin tests from the 392 tests performed in patients with a positive history of antibiotic hypersensitivity (1 6.58%) and 23 positive skin tests from the 288 performed in controls (7.98%), the two incidences showing significant statistical difference (p = 0.0011). The relative risk for having a positive skin test for NMBAs for patients versus controls was 1.77 (1.15-2.76). For atracurium, skin tests were more often positive in patients with a positive history of antibiotic hypersensitivity versus controls (p = 0.02). For pancuronium, rocuronium and suxamethonium the statistical difference was not attained (p-values 0.08 for pancuronium, 0.23 for rocuronium, and 0.26 for suxamethonium). Patients with a positive history of antibiotic hypersensitivity seem to have a higher incidence of positive skin tests for NMBAs. They might represent a group at higher risk for developing intraoperative anaphylaxis compared to the general population. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Effects of Neuromuscular Electrical Stimulation During Hemodialysis on Peripheral Muscle Strength and Exercise Capacity: A Randomized Clinical Trial.

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Brüggemann, Ana Karla; Mello, Carolina Luana; Dal Pont, Tarcila; Hizume Kunzler, Deborah; Martins, Daniel Fernandes; Bobinski, Franciane; Pereira Yamaguti, Wellington; Paulin, Elaine

2017-05-01

To evaluate the effects of neuromuscular electrical stimulation of high and low frequency and intensity, performed during hemodialysis, on physical function and inflammation markers in patients with chronic kidney disease (CKD). Randomized clinical trial. Hemodialysis clinic. Patients with CKD (N=51) were randomized into blocks of 4 using opaque sealed envelopes. They were divided into a group of high frequency and intensity neuromuscular electrical stimulation and a group of low frequency and intensity neuromuscular electrical stimulation. The high frequency and intensity neuromuscular electrical stimulation group was submitted to neuromuscular electrical stimulation at a frequency of 50Hz and a medium intensity of 72.90mA, and the low frequency and intensity neuromuscular electrical stimulation group used a frequency of 5Hz and a medium intensity of 13.85mA, 3 times per week for 1 hour, during 12 sessions. Peripheral muscle strength, exercise capacity, levels of muscle trophism marker (insulin growth factor 1) and levels of proinflammatory (tumor necrosis factor α) and anti-inflammatory (interleukin 10) cytokines. The high frequency and intensity neuromuscular electrical stimulation group showed a significant increase in right peripheral muscle strength (155.35±65.32Nm initial vs 161.60±68.73Nm final; P=.01) and left peripheral muscle strength (156.60±66.51Nm initial vs 164.10±69.76Nm final; P=.02) after the training, which did not occur in the low frequency and intensity neuromuscular electrical stimulation group for both right muscle strength (109.40±32.08Nm initial vs 112.65±38.44Nm final; P=.50) and left muscle strength (113.65±37.79Nm initial vs 116.15±43.01Nm final; P=.61). The 6-minute walk test distance (6MWTD) increased in both groups: high frequency and intensity neuromuscular electrical stimulation group (435.55±95.81m initial vs 457.25±90.64m final; P=.02) and low frequency and intensity neuromuscular electrical stimulation group (403.80�

Neuromuscular adaptations induced by adjacent joint training.

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Ema, R; Saito, I; Akagi, R

2018-03-01

Effects of resistance training are well known to be specific to tasks that are involved during training. However, it remains unclear whether neuromuscular adaptations are induced after adjacent joint training. This study examined the effects of hip flexion training on maximal and explosive knee extension strength and neuromuscular performance of the rectus femoris (RF, hip flexor, and knee extensor) compared with the effects of knee extension training. Thirty-seven untrained young men were randomly assigned to hip flexion training, knee extension training, or a control group. Participants in the training groups completed 4 weeks of isometric hip flexion or knee extension training. Standardized differences in the mean change between the training groups and control group were interpreted as an effect size, and the substantial effect was assumed to be ≥0.20 of the between-participant standard deviation at baseline. Both types of training resulted in substantial increases in maximal (hip flexion training group: 6.2% ± 10.1%, effect size = 0.25; knee extension training group: 20.8% ± 9.9%, effect size = 1.11) and explosive isometric knee extension torques and muscle thickness of the RF in the proximal and distal regions. Improvements in strength were accompanied by substantial enhancements in voluntary activation, which was determined using the twitch interpolation technique and RF activation. Differences in training effects on explosive torques and neural variables between the two training groups were trivial. Our findings indicate that hip flexion training results in substantial neuromuscular adaptations during knee extensions similar to those induced by knee extension training. © 2017 The Authors. Scandinavian Journal of Medicine & Science In Sports Published by John Wiley & Sons Ltd.

BIOLOGY OF SOME NEUROMUSCULAR DISORDERS

Directory of Open Access Journals (Sweden)

Gerta Vrbova

2004-12-01

unit is slower. The rate of maturation is critical for the survival of both motoneurone and muscle and that events that interfere with the time course of maturation cause both motoneurone and muscle fibre death. The proposal that the SMN gene/protein is involved in the process to developmental changes in cells and therefore crucial for their survival is put forward. The understanding of the developmental changes and their influence on motoneurone and muscle survival may help to devise therapeutic interventions. These may include a protection of the motoneurone cell body during a critical period of its development by reducing its excitability or enhancing its defences by upregulating heat shock proteins, b stabilizing neuromuscular junctions to enhance and prolong the retrograde influences from the muscle that affect motoneurone survival, c protecting muscle fibres from apoptosis, as well as stimulating their maturation by activity appropriate to their younger age that results from their delayed development.These approaches should be considered in addition to or in conjunction with possible interference with the gene and its product.In order to understand and possibly interfere/treat neuromuscular disorders it is important to analyze the biological events that may be causing the disability. In this presentation I would illustrate such attempts on two examples of genetically determined neuromuscular diseases: 1 Duchenne muscular dystrophy, and 2 Spinal muscular atrophy.

S-nitrosoglutathione reductase deficiency-induced S-nitrosylation results in neuromuscular dysfunction.

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Montagna, Costanza; Di Giacomo, Giuseppina; Rizza, Salvatore; Cardaci, Simone; Ferraro, Elisabetta; Grumati, Paolo; De Zio, Daniela; Maiani, Emiliano; Muscoli, Carolina; Lauro, Filomena; Ilari, Sara; Bernardini, Sergio; Cannata, Stefano; Gargioli, Cesare; Ciriolo, Maria R; Cecconi, Francesco; Bonaldo, Paolo; Filomeni, Giuseppe

2014-08-01

Nitric oxide (NO) production is implicated in muscle contraction, growth and atrophy, and in the onset of neuropathy. However, many aspects of the mechanism of action of NO are not yet clarified, mainly regarding its role in muscle wasting. Notably, whether NO production-associated neuromuscular atrophy depends on tyrosine nitration or S-nitrosothiols (SNOs) formation is still a matter of debate. Here, we aim at assessing this issue by characterizing the neuromuscular phenotype of S-nitrosoglutathione reductase-null (GSNOR-KO) mice that maintain the capability to produce NO, but are unable to reduce SNOs. We demonstrate that, without any sign of protein nitration, young GSNOR-KO mice show neuromuscular atrophy due to loss of muscle mass, reduced fiber size, and neuropathic behavior. In particular, GSNOR-KO mice show a significant decrease in nerve axon number, with the myelin sheath appearing disorganized and reduced, leading to a dramatic development of a neuropathic phenotype. Mitochondria appear fragmented and depolarized in GSNOR-KO myofibers and myotubes, conditions that are reverted by N-acetylcysteine treatment. Nevertheless, although atrogene transcription is induced, and bulk autophagy activated, no removal of damaged mitochondria is observed. These events, alongside basal increase of apoptotic markers, contribute to persistence of a neuropathic and myopathic state. Our study provides the first evidence that GSNOR deficiency, which affects exclusively SNOs reduction without altering nitrotyrosine levels, results in a clinically relevant neuromuscular phenotype. These findings provide novel insights into the involvement of GSNOR and S-nitrosylation in neuromuscular atrophy and neuropathic pain that are associated with pathological states; for example, diabetes and cancer.

Alterations in neuromuscular function in girls with generalized joint hypermobility

DEFF Research Database (Denmark)

Jensen, Bente Rona; Melcher, Jesper Sandfeld; Melcher, Pia Grethe Sandfeld

2016-01-01

BACKGROUND: Generalized Joint Hypermobility (GJH) is associated with increased risk of musculoskeletal joint pain. We investigated neuromuscular performance and muscle activation strategy. METHODS: Girls with GJH and non-GJH (NGJH) performed isometric knee flexions (90°,110°,130°), and extensions...

Ultrasound-guided paravertebral block for pyloromyotomy in 3 neonates with congenital hypertrophic pyloric stenosis

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Javier Mata-Gómez

2015-08-01

Full Text Available BACKGROUND AND OBJECTIVES: Hypertrophic pyloric stenosis is a relatively common affection of gastrointestinal tract in childhood that results in symptoms, such as projectile vomiting and metabolic disorders that imply a high risk of aspiration during anesthetic induction. In this way, the carrying out of a technique with general anesthesia and intravenous rapid sequence induction, preoxygenation and cricoid pressure are recommended. After the correction of systemic metabolic alkalosis and pH normalization, cerebrospinal fluid can keep a state of metabolic alkalosis. This circumstance, in addition to the residual effect of neuromuscular blocking agents, inhalant anesthetics and opioids could increase the risk of postoperative apnea after a general anesthesia.CASE REPORT: We present the successful management in 3 neonates in those a pyloromyotomy was carried out because they had presented congenital hypertrophic pyloric stenosis. This procedure was done under general anesthesia with orotracheal intubation and rapid sequence induction. Then, ultrasound-guided paravertebral block was performed as analgesic method without the need for administrating opioids within intraoperative period and keeping an appropriate analgesic level.CONCLUSIONS: Local anesthesia has demonstrated to be safe and effective in pediatric practice. We consider the ultrasound-guided paravertebral block with one dose as a possible alternative for other local techniques described, avoiding the use of opioids and neuromuscular blocking agents during general anesthesia, and reducing the risk of central apnea within postoperative period.

Elbow joint position sense after neuromuscular training with handheld vibration.

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Tripp, Brady L; Faust, Donald; Jacobs, Patrick

2009-01-01

Clinicians use neuromuscular control exercises to enhance joint position sense (JPS); however, because standardizing such exercises is difficult, validations of their use are limited. To evaluate the acute effects of a neuromuscular training exercise with a handheld vibrating dumbbell on elbow JPS acuity. Crossover study. University athletic training research laboratory. Thirty-one healthy, college-aged volunteers (16 men, 15 women, age = 23 + or - 3 years, height = 173 + or - 8 cm, mass = 76 + or - 14 kg). We measured and trained elbow JPS using an electromagnetic tracking device that provided auditory and visual biofeedback. For JPS testing, participants held a dumbbell and actively identified the target elbow flexion angle (90 degrees ) using the software-generated biofeedback, followed by 3 repositioning trials without feedback. Each neuromuscular training protocol included 3 exercises during which participants held a 2.55-kg dumbbell vibrating at 15, 5, or 0 Hz and used software-generated biofeedback to locate and maintain the target elbow flexion angle for 15 seconds. We calculated absolute (accuracy) and variable (variability) errors using the differences between target and reproduced angles. Training protocols using 15-Hz vibration enhanced accuracy and decreased variability of elbow JPS (P or = .200). Our results suggest these neuromuscular control exercises, which included low-magnitude, low-frequency handheld vibration, may enhance elbow JPS. Future researchers should examine vibration of various durations and frequencies, should include injured participants and functional multijoint and multiplanar measures, and should examine long-term effects of training protocols on JPS and injury.

A Markov computer simulation model of the economics of neuromuscular blockade in patients with acute respiratory distress syndrome

Directory of Open Access Journals (Sweden)

Chow John L

2006-03-01

Full Text Available Abstract Background Management of acute respiratory distress syndrome (ARDS in the intensive care unit (ICU is clinically challenging and costly. Neuromuscular blocking agents may facilitate mechanical ventilation and improve oxygenation, but may result in prolonged recovery of neuromuscular function and acute quadriplegic myopathy syndrome (AQMS. The goal of this study was to address a hypothetical question via computer modeling: Would a reduction in intubation time of 6 hours and/or a reduction in the incidence of AQMS from 25% to 21%, provide enough benefit to justify a drug with an additional expenditure of $267 (the difference in acquisition cost between a generic and brand name neuromuscular blocker? Methods The base case was a 55 year-old man in the ICU with ARDS who receives neuromuscular blockade for 3.5 days. A Markov model was designed with hypothetical patients in 1 of 6 mutually exclusive health states: ICU-intubated, ICU-extubated, hospital ward, long-term care, home, or death, over a period of 6 months. The net monetary benefit was computed. Results Our computer simulation modeling predicted the mean cost for ARDS patients receiving standard care for 6 months to be $62,238 (5% – 95% percentiles $42,259 – $83,766, with an overall 6-month mortality of 39%. Assuming a ceiling ratio of $35,000, even if a drug (that cost $267 more hypothetically reduced AQMS from 25% to 21% and decreased intubation time by 6 hours, the net monetary benefit would only equal $137. Conclusion ARDS patients receiving a neuromuscular blocker have a high mortality, and unpredictable outcome, which results in large variability in costs per case. If a patient dies, there is no benefit to any drug that reduces ventilation time or AQMS incidence. A prospective, randomized pharmacoeconomic study of neuromuscular blockers in the ICU to asses AQMS or intubation times is impractical because of the highly variable clinical course of patients with ARDS.

Neuromuscular function during stair descent in meniscectomized patients and controls

DEFF Research Database (Denmark)

Thorlund, Jonas Bloch; Roos, Ewa M; Aagaard, Per

2011-01-01

The aim of this study was to identify differences in knee range of motion (ROM), movement speed, ground reaction forces (GRF) profile, neuromuscular activity, and muscle coactivation during the transition between stair descent and level walking in meniscectomized patients at high risk of knee...

Synaptic activity-related classical protein kinase C isoform localization in the adult rat neuromuscular synapse.

Science.gov (United States)

Besalduch, Núria; Tomàs, Marta; Santafé, Manel M; Garcia, Neus; Tomàs, Josep; Lanuza, Maria Angel

2010-01-10

Protein kinase C (PKC) is essential for signal transduction in a variety of cells, including neurons and myocytes, and is involved in both acetylcholine release and muscle fiber contraction. Here, we demonstrate that the increases in synaptic activity by nerve stimulation couple PKC to transmitter release in the rat neuromuscular junction and increase the level of alpha, betaI, and betaII isoforms in the membrane when muscle contraction follows the stimulation. The phosphorylation activity of these classical PKCs also increases. It seems that the muscle has to contract in order to maintain or increase classical PKCs in the membrane. We use immunohistochemistry to show that PKCalpha and PKCbetaI were located in the nerve terminals, whereas PKCalpha and PKCbetaII were located in the postsynaptic and the Schwann cells. Stimulation and contraction do not change these cellular distributions, but our results show that the localization of classical PKC isoforms in the membrane is affected by synaptic activity.

Training the Antifragile Athlete: A Preliminary Analysis of Neuromuscular Training Effects on Muscle Activation Dynamics.

Science.gov (United States)

Kiefer, Adam W; Myer, Gregory D

2015-10-01

Athletic injuries typically occur when the stable, emergent coordination between behavioral processes breaks down due to external noise, or variability. A physiological system that operates at an optimal point on a spectrum of rigidity and flexibility may be better prepared to handle extreme external variability, and the purpose of the current experiment was to examine whether targeted neuromuscular training resulted in changes to the rigidity and flexibility of the gluteal muscle tonus signal as measured with electromyography prior to the landing phase of a drop vertical jump task. 10 adolescent female athletes who participated in a targeted 10-week neuromuscular training program and 6 controls participated, and their tonus dynamics were examined with recurrence quantification analysis prior to training and after the 10-week program. The dependent measures, percent laminarity (%LAM) and percent determinism (%DET) were hypothesized to decrease following training, and were submitted to a one tailed mixed-model ANOVA. The training group exhibited a decrease in %LAM and %DET after training compared to pre-training and controls. The present findings indicate increased metaflexibility (i.e., greater intermittency and an increase in internal randomness) in tonus dynamics following neuromuscular training, and have important implications for the prevention of musculoskeletal injury in sport, specifically within the context of external noise and antifragility.

The role of patient advocacy organisations in neuromuscular disease R&D - The case of the Dutch neuromuscular disease association VSN

NARCIS (Netherlands)

Boon, W.P.C.; Broekgaarden, R.

2010-01-01

This article investigates to what extent patient advocacy organisations play a role in influencing R&D and policymaking for rare neuromuscular diseases. The Dutch neuromuscular disease organisation VSN is studied in depth. A brief history of the VSN is sketched along with the international

PRELIMINARY INVESTIGATIONS OF THE CLINICAL-PHARMACOLOGY OF 3 SHORT-ACTING NONDEPOLARIZING NEUROMUSCULAR BLOCKING-AGENTS, ORG 9453, ORG 9489 AND ORG 9487

NARCIS (Netherlands)

WIERDA, JMKH; BEAUFORT, AM; KLEEF, UW; SMEULERS, NJ; AGOSTON, S

Three muscle relaxants, Org 9453, Org 9489 and Org 9487, short-acting in animals, were investigated to establish their profiles in humans. Potency, time course of action, and pharmacokinetic behaviour were studied in 90 healthy patients during fentanyl/halothane/N2O anaesthesia. Neuromuscular

Medical back belt with integrated neuromuscular electrical stimulation

NARCIS (Netherlands)

Bottenberg, E. (Eliza); Brinks, G.J. (Ger); Hesse, J. (Jenny)

2014-01-01

The medical back belt with integrated neuromuscular electrical stimulation is anorthopedic device, which has two main functions. The first function is to stimulate the backmuscles by using a neuromuscular electrical stimulation device that releases regular,electrical impulses. The second function of

Novel vibration-exercise instrument with dedicated adaptive filtering for electromyographic investigation of neuromuscular activation

NARCIS (Netherlands)

Xu, L.; Rabotti, C.; Mischi, M.

2012-01-01

Vibration exercise (VE) has been suggested as an effective methodology to improve muscle strength and power performance. Several studies link the effects of vibration training to enhanced neuromuscular demand, typically ascribed to involuntary reflex mechanisms. However, the underlying mechanisms

Recent advances in antisense oligonucleotide therapy in genetic neuromuscular diseases

Directory of Open Access Journals (Sweden)

Ashok Verma

2018-01-01

Full Text Available Genetic neuromuscular diseases are caused by defective expression of nuclear or mitochondrial genes. Mutant genes may reduce expression of wild-type proteins, and strategies to activate expression of the wild-type proteins might provide therapeutic benefits. Also, a toxic mutant protein may cause cell death, and strategies that reduce mutant gene expression may provide therapeutic benefit. Synthetic antisense oligonucleotide (ASO can recognize cellular RNA and control gene expression. In recent years, advances in ASO chemistry, creation of designer ASO molecules to enhance their safety and target delivery, and scientific controlled clinical trials to ascertain their therapeutic safety and efficacy have led to an era of plausible application of ASO technology to treat currently incurable neuromuscular diseases. Over the past 1 year, for the first time, the United States Food and Drug Administration has approved two ASO therapies in genetic neuromuscular diseases. This overview summarizes the recent advances in ASO technology, evolution and use of synthetic ASOs as a therapeutic platform, and the mechanism of ASO action by exon-skipping in Duchenne muscular dystrophy and exon-inclusion in spinal muscular atrophy, with comments on their advantages and limitations.

Electrical stimulation for physiologic measurement of neuromuscular function and respiratory support during anticholinesterase poisoning. Annual report, October 1983-September 1984

Energy Technology Data Exchange (ETDEWEB)

Yodlowski, E.H.

1984-10-01

The purpose of this research is to develop the techniques necessary for providing short-term respiratory support for personnel poisoned by organophosphate agents. Following acute exposure to organophosphate compounds, respiration ceases before cardiovascular collapse occurs. Military personnel exposed to these compounds in the field are most likely to die from asphyxiation. By virtue of their ability to cross the blood-brain barrier and inhibit cholinesterase activity the organophosphates are capable of interrupting control of respiration either centrally (i.e. within the central nervous system) or peripherally by blocking neuromuscular transmission or contraction coupling at the peripheral muscles. We hypothesize that it will be possible to overcome organophosphate induced respiratory arrest by providing artificial respiratory pacing. This research is aimed at producing a means of respiratory support via electronic stimulation of the phrenic nerve (s) that can be used when central respiratory drive has become blocked by organophosphate agents. Animal experiments have been conducted to implement and evaluate the transesophageal electrophrenic stimulation technique (TEST) for respiratory pacing and to determine appropriate stimulation parameters to produce effective and efficient respirations.

Neuromuscular adaptations predict functional disability independently of clinical pain and psychological factors in patients with chronic non-specific low back pain.

Science.gov (United States)

Dubois, Jean-Daniel; Abboud, Jacques; St-Pierre, Charles; Piché, Mathieu; Descarreaux, Martin

2014-08-01

Patients with chronic low back pain exhibit characteristics such as clinical pain, psychological symptoms and neuromuscular adaptations. The purpose of this study was to determine the independent contribution of clinical pain, psychological factors and neuromuscular adaptations to disability in patients with chronic low back pain. Clinical pain intensity, pain catastrophizing, fear-avoidance beliefs, anxiety, neuromuscular adaptations to chronic pain and neuromuscular responses to experimental pain were assessed in 52 patients with chronic low back pain. Lumbar muscle electromyographic activity was assessed during a flexion-extension task (flexion relaxation phenomenon) to assess both chronic neuromuscular adaptations and neuromuscular responses to experimental pain during the task. Multiple regressions showed that independent predictors of disability included neuromuscular adaptations to chronic pain (β=0.25, p=0.006, sr(2)=0.06), neuromuscular responses to experimental pain (β=-0.24, p=0.011, sr(2)=0.05), clinical pain intensity (β=0.28, p=0.002, sr(2)=0.08) and psychological factors (β=0.58, ppain intensity and psychological factors, and contribute to inter-individual differences in patients' disability. This suggests that disability, in chronic low back pain patients, is determined by a combination of factors, including clinical pain, psychological factors and neuromuscular adaptations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Deficits in Endogenous Adenosine Formation by Ecto-5′-Nucleotidase/CD73 Impair Neuromuscular Transmission and Immune Competence in Experimental Autoimmune Myasthenia Gravis

Directory of Open Access Journals (Sweden)

Laura Oliveira

2015-01-01

Full Text Available AMP dephosphorylation via ecto-5′-nucleotidase/CD73 is the rate limiting step to generate extracellular adenosine (ADO from released adenine nucleotides. ADO, via A2A receptors (A2ARs, is a potent modulator of neuromuscular and immunological responses. The pivotal role of ecto-5′-nucleotidase/CD73, in controlling extracellular ADO formation, prompted us to investigate its role in a rat model of experimental autoimmune myasthenia gravis (EAMG. Results show that CD4+CD25+FoxP3+ regulatory T cells express lower amounts of ecto-5′-nucleotidase/CD73 as compared to controls. Reduction of endogenous ADO formation might explain why proliferation of CD4+ T cells failed upon blocking A2A receptors activation with ZM241385 or adenosine deaminase in EAMG animals. Deficits in ADO also contribute to neuromuscular transmission failure in EAMG rats. Rehabilitation of A2AR-mediated immune suppression and facilitation of transmitter release were observed by incubating the cells with the nucleoside precursor, AMP. These findings, together with the characteristic increase in serum adenosine deaminase activity of MG patients, strengthen our hypothesis that the adenosinergic pathway may be dysfunctional in EAMG. Given that endogenous ADO formation is balanced by ecto-5′-nucleotidase/CD73 activity and that A2ARs exert a dual role to restore use-dependent neurocompetence and immune suppression in myasthenics, we hypothesize that stimulation of the two mechanisms may have therapeutic potential in MG.

Optimizing referral of patients with neuromuscular disorders to allied health care.

NARCIS (Netherlands)

Pieterse, A.J.; Cup, E.H.C.; Akkermans, R.P.; Hendricks, H.T.; Engelen, B.G.M. van; Wilt, G.J. van der; Oostendorp, R.A.B.

2009-01-01

BACKGROUND AND PURPOSE: To report the predictive validity of the perceived limitations in activities and need questionnaire (PLAN-Q), a screening instrument to support neurologists to select patients with neuromuscular disorders (NMD) for referral for a one-off consultation by occupational therapist

What occupant kinematics and neuromuscular responses tell us about whiplash injury.

Science.gov (United States)

Siegmund, Gunter P

2011-12-01

Literature-based review. To review the published data on occupant kinematic and neuromuscular responses during low-speed impacts and analyze how these data inform our understanding of whiplash injury. A stereotypical kinematic and neuromuscular response has been observed in human subjects exposed to rear-end impacts. Combined with various models of injury, these response data have been used to develop anti-whiplash seats that prevent whiplash injury in many, but not all, individuals exposed to a rear-end crash. Synthesis of the literature. Understanding of the occupant kinematics and neuromuscular responses, combined with data from various seat-related interventions, have shown that differential motion between the superior and inferior ends of the cervical spine is responsible for many whiplash injuries. The number of whiplash injuries not prevented by current anti-whiplash seats suggests than further work remains, possibly related to designing seats that respond dynamically to the occupant and collision properties. Neck muscles alter the head and neck kinematics during the interval in which injury likely occurs, even in initially relaxed occupants. It remains unclear whether muscle activation mitigates or exacerbates whiplash injury. If muscle activation mitigates injury, then advance warning could be used to help occupant tense their muscles before impact. Alternatively, if muscle activation exacerbates whiplash injury, then a loud preimpact sound that uncouples the startle and postural components of the muscle response could reduce peak muscle activation during a whiplash exposure. Our improved understanding of whiplash injury has led to anti-whiplash seats that have prevented many whiplash injuries. Further work remains to optimize these and possibly other systems to further reduce the number of whiplash injuries.

Reversal of Vecuronium-induced Neuromuscular Blockade with Low-dose Sugammadex at Train-of-four Count of Four: A Randomized Controlled Trial.

Science.gov (United States)

Asztalos, László; Szabó-Maák, Zoltán; Gajdos, András; Nemes, Réka; Pongrácz, Adrienn; Lengyel, Szabolcs; Fülesdi, Béla; Tassonyi, Edömér

2017-09-01

Rocuronium-induced neuromuscular block that spontaneously recovered to a train-of-four count of four can be reversed with sugammadex 0.5 or 1.0 mg/kg. We investigated whether these doses of sugammadex can also reverse vecuronium at a similar level of block. Sixty-five patients were randomly assigned, and 64 were analyzed in this controlled, superiority study. Participants received general anesthesia with propofol, sevoflurane, fentanyl, and vecuronium. Measurement of neuromuscular function was performed with acceleromyography (TOF-Watch-SX, Organon Teknika B.V., The Netherlands ). Once the block recovered spontaneously to four twitches in response to train-of-four stimulation, patients were randomly assigned to receive sugammadex 0.5, 1.0, or 2.0 mg/kg; neostigmine 0.05 mg/kg; or placebo. Time from study drug injection to normalized train-of-four ratio 0.9 and the incidence of incomplete reversal within 30 min were the primary outcome variables. Secondary outcome was the incidence of reparalysis (normalized train-of-four ratio less than 0.9). Sugammadex, in doses of 1.0 and 2.0 mg/kg, reversed a threshold train-of-four count of four to normalized train-of-four ratio of 0.9 or higher in all patients in 4.4 ± 2.3 min (mean ± SD) and 2.6 ± 1.6 min, respectively. Sugammadex 0.5 mg/kg reversed the block in 6.8 ± 4.1 min in 70% of patients (P 0.05 vs. sugammadex 0.5 mg/kg). The overall frequency of reparalysis was 18.7%, but this incidence varied from group to group. Sugammadex 1.0 mg/kg, unlike 0.5 mg/kg, properly reversed a threshold train-of-four count of four vecuronium-induced block but did not prevent reparalysis.

Computed tomography (CT) in neuromuscular disorders

International Nuclear Information System (INIS)

Novak, M.; Ambler, Z.

1997-01-01

For 24 patients with confirmed neuromuscular disorders, the clinical picture of the disease was complemented with CT examination. It is concluded, in accordance with the literature, that CT has a supplementary value as regards the extent and degree of disorder of the affected muscle groups. The basic pathological picture includes muscular atrophies, dystrophies, hypertrophies, and their combinations. The CT images are non-specific for the individual neuromuscular disorders and are of minor importance in the diagnostic process. 1 tab., 7 figs., 6 refs

The effects of neuromuscular training on knee joint motor control during sidecutting in female elite soccer and handball players

DEFF Research Database (Denmark)

Zebis, Mette K; Bencke, Jesper; Andersen, Lars

2008-01-01

and knee, and ground reaction forces were recorded during a sidecutting maneuver. Neuromuscular activity in the prelanding phase was obtained 10 and 50 ms before foot strike on a force plate and at 10 and 50 ms after foot strike on a force plate. RESULTS: Neuromuscular training markedly increased before...

[Perioperative management of a patient with myotonic dystrophy developing the cardiac symptoms initially prior to the neuromuscular symptoms].

Science.gov (United States)

Wake, M; Matsushita, M; Aono, H; Matsumoto, M; Kohri, Y

1994-08-01

The authors anesthetized a 48-year-old woman with endometrial cancer and a large ovarian cyst. She developed cardiac failure initially followed by the sick sinus syndrome and A-V block from hypertrophic cardiomyopathy, prior to neuromuscular symptoms. Epidural anesthesia assisted by general anesthesia was carried out safely without intravenous administration of any muscle relaxants. From this experience, it is considered that epidural anesthesia assisted with some other proper methods is suitable for surgery of lower abdomen.

Effects of napping on neuromuscular fatigue in myasthenia gravis.

Science.gov (United States)

Kassardjian, Charles D; Murray, Brian J; Kokokyi, Seint; Jewell, Dana; Barnett, Carolina; Bril, Vera; Katzberg, Hans D

2013-11-01

The relationship between sleep and neuromuscular fatigue is understood poorly. The goal of this study was to evaluate the effects of napping on quantitative measures of neuromuscular fatigue in patients with myasthenia gravis (MG). Eight patients with mild to moderate MG were recruited. Patients underwent maintenance of wakefulness tests (MWT) and multiple sleep latency tests (MSLT). The Quantitative Myasthenia Gravis Score (QMGS) was measured before nap and after each nap to examine the effects of napping and sleep on neuromuscular weakness. Results showed that QMGS improves only after naps where patients slept more than 5 min but not where patients did not sleep or slept less than 5 min. Daytime napping mitigates neuromuscular fatigue in patients with MG, especially if patients slept for more than 5 min. Copyright © 2013 Wiley Periodicals, Inc.

Neuromuscular training based on whole body vibration in children with spina bifida: a retrospective analysis of a new physiotherapy treatment program.

Science.gov (United States)

Stark, C; Hoyer-Kuhn, H-K; Semler, O; Hoebing, L; Duran, I; Cremer, R; Schoenau, E

2015-02-01

Spina bifida is the most common congenital cause of spinal cord lesions resulting in paralysis and secondary conditions like osteoporosis due to immobilization. Physiotherapy is performed for optimizing muscle function and prevention of secondary conditions. Therefore, training of the musculoskeletal system is one of the major aims in the rehabilitation of children with spinal cord lesions. The neuromuscular physiotherapy treatment program Auf die Beine combines 6 months of home-based whole body vibration (WBV) with interval blocks at the rehabilitation center: 13 days of intensive therapy at the beginning and 6 days after 3 months. Measurements are taken at the beginning (M0), after 6 months of training (M6), and after a 6-month follow-up period (M12). Gait parameters are assessed by ground reaction force and motor function by the Gross Motor Function Measurement (GMFM-66). Sixty children (mean age 8.71 ± 4.7 years) who participated in the program until February 2014 were retrospectively analyzed. Walking velocity improved significantly by 0.11 m/s (p = 0.0026) and mobility (GMFM-66) by 2.54 points (p = 0.001) after the training. All changes at follow-up were not significant, but significant changes were observed after the training period. Decreased contractures were observed with increased muscle function. Significant improvements in motor function were observed after the active training period of the new neuromuscular training concept. This first analysis of the new neuromuscular rehabilitation concept Auf die Beine showed encouraging results for a safe and efficient physiotherapy treatment program which increases motor function in children with spina bifida.

Fatiguing exercise intensity influences the relationship between parameters reflecting neuromuscular function and postural control variables.

Directory of Open Access Journals (Sweden)

Sébastien Boyas

Full Text Available The purpose of this study was to investigate the influence of fatiguing exercise intensity on the nature and extent of fatigue-induced changes in neuromuscular function and postural stability in quiet standing. We also explored the contribution of selected neuromuscular mechanisms involved in force production to postural stability impairment observed following fatigue using an approach based on multivariate regressions. Eighteen young subjects performed 30-s postural trials on one leg with their eyes closed. Postural trials were performed before and after fatiguing exercises of different intensities: 25, 50 and 75% of maximal isometric plantarflexor torque. Fatiguing exercises consisted of sustaining a plantarflexor isometric contraction at the target intensity until task failure. Maximal isometric plantarflexor torque, electromyographic activity of plantarflexor and dorsiflexor muscles, activation level (twitch interpolation technique and twitch contractile properties of plantarflexors were used to characterize neuromuscular function. The 25% exercise was associated with greater central fatigue whereas the 50 and 75% exercises involved mostly peripheral fatigue. However, all fatiguing exercises induced similar alterations in postural stability, which was unexpected considering previous literature. Stepwise multiple regression analyses showed that fatigue-related changes in selected parameters related to neuromuscular function could explain more than half (0.51≤R(2≤0.82 of the changes in postural variables for the 25% exercise. On the other hand, regression models were less predictive (0.17≤R(2≤0.73 for the 50 and 75% exercises. This study suggests that fatiguing exercise intensity does not influence the extent of postural stability impairment, but does influence the type of fatigue induced and the neuromuscular function predictors explaining changes in postural variables.

Postoperative Residual Neuromuscular Paralysis at an Australian Tertiary Children’s Hospital

Directory of Open Access Journals (Sweden)

Thomas Ledowski

2015-01-01

Full Text Available Purpose. Residual neuromuscular blockade (RNMB is known to be a significant but frequently overlooked complication after the use of neuromuscular blocking agents (NMBA. Aim of this prospective audit was to investigate the incidence and severity of RNMB at our Australian tertiary pediatric center. Methods. All children receiving NMBA during anesthesia were included over a 5-week period at the end of 2011 (Mondays to Fridays; 8 a.m.–6 p.m.. At the end of surgery, directly prior to tracheal extubation, the train-of-four (TOF ratio was assessed quantitatively. Data related to patient postoperative outcome was collected in the postoperative acute care unit. Results. Data of 64 patients were analyzed. Neostigmine was given in 34 cases and sugammadex in 1 patient. The incidence of RNMB was 28.1% overall (without reversal: 19.4%; after neostigmine: 37.5%; n.s.. Severe RNMB (TOF ratio < 0.7 was found in 6.5% after both no reversal and neostigmine, respectively. Complications in the postoperative acute care unit were infrequent, with no differences between reversal and no reversal groups. Conclusions. In this audit, RNMB was frequently observed, particularly in cases where patients were reversed with neostigmine. These findings underline the well-known problems associated with the use of NMBA that are not fully reversed.

Protein kinase C isoforms at the neuromuscular junction: localization and specific roles in neurotransmission and development.

Science.gov (United States)

Lanuza, Maria A; Santafe, Manel M; Garcia, Neus; Besalduch, Núria; Tomàs, Marta; Obis, Teresa; Priego, Mercedes; Nelson, Phillip G; Tomàs, Josep

2014-01-01

The protein kinase C family (PKC) regulates a variety of neural functions including neurotransmitter release. The selective activation of a wide range of PKC isoforms in different cells and domains is likely to contribute to the functional diversity of PKC phosphorylating activity. In this review, we describe the isoform localization, phosphorylation function, regulation and signalling of the PKC family at the neuromuscular junction. Data show the involvement of the PKC family in several important functions at the neuromuscular junction and in particular in the maturation of the synapse and the modulation of neurotransmission in the adult. © 2013 Anatomical Society.

Whole-body vibration does not influence knee joint neuromuscular function or proprioception.

Science.gov (United States)

Hannah, R; Minshull, C; Folland, J P

2013-02-01

This study examined the acute effects of whole-body vibration (WBV) on knee joint position sense and indices of neuromuscular function, specifically strength, electromechanical delay and the rate of force development. Electromyography and electrically evoked contractions were used to investigate neural and contractile responses to WBV. Fourteen healthy males completed two treatment conditions on separate occasions: (1) 5 × 1 min of unilateral isometric squat exercise on a synchronous vibrating platform [30 Hz, 4 mm peak-to-peak amplitude] (WBV) and (2) a control condition (CON) of the same exercise without WBV. Knee joint position sense (joint angle replication task) and quadriceps neuromuscular function were assessed pre-, immediately-post and 1 h post-exercise. During maximum voluntary knee extensions, the peak force (PF(V)), electromechanical delay (EMD(V)), rate of force development (RFD(V)) and EMG of the quadriceps were measured. Twitch contractions of the knee extensors were electrically evoked to assess EMD(E) and RFD(E). The results showed no influence of WBV on knee joint position, EMD(V), PF(V) and RFD(V) during the initial 50, 100 or 150 ms of contraction. Similarly, electrically evoked neuromuscular function and neural activation remained unchanged following the vibration exercise. A single session of unilateral WBV did not influence any indices of thigh muscle neuromuscular performance or knee joint proprioception. © 2011 John Wiley & Sons A/S.

Glial processes at the Drosophila larval neuromuscular junction match synaptic growth.

Directory of Open Access Journals (Sweden)

Deidre L Brink

Full Text Available Glia are integral participants in synaptic physiology, remodeling and maturation from blowflies to humans, yet how glial structure is coordinated with synaptic growth is unknown. To investigate the dynamics of glial development at the Drosophila larval neuromuscular junction (NMJ, we developed a live imaging system to establish the relationship between glia, neuronal boutons, and the muscle subsynaptic reticulum. Using this system we observed processes from two classes of peripheral glia present at the NMJ. Processes from the subperineurial glia formed a blood-nerve barrier around the axon proximal to the first bouton. Processes from the perineurial glial extended beyond the end of the blood-nerve barrier into the NMJ where they contacted synapses and extended across non-synaptic muscle. Growth of the glial processes was coordinated with NMJ growth and synaptic activity. Increasing synaptic size through elevated temperature or the highwire mutation increased the extent of glial processes at the NMJ and conversely blocking synaptic activity and size decreased the presence and size of glial processes. We found that elevated temperature was required during embryogenesis in order to increase glial expansion at the nmj. Therefore, in our live imaging system, glial processes at the NMJ are likely indirectly regulated by synaptic changes to ensure the coordinated growth of all components of the tripartite larval NMJ.

Glutamatergic postsynaptic block by Pamphobeteus spider venoms in crayfish.

Science.gov (United States)

Araque, A; Ferreira, W; Lucas, S; Buño, W

1992-01-31

The effects of toxins from venom glands of two south american spiders (Pamphobeteus platyomma and P. soracabae) on glutamatergic excitatory synaptic transmission were studied in the neuromuscular junction of the opener muscle of crayfish. The toxins selectively and reversibly blocked both excitatory postsynaptic currents and potentials in a dose-dependent manner. They also reversibly abolished glutamate-induced postsynaptic membrane depolarization. They had no effect on resting postsynaptic membrane conductance nor on postsynaptic voltage-gated currents. The synaptic facilitation and the frequency of miniature postsynaptic potentials were unaffected by the toxins, indicating that presynaptic events were not modified. Picrotoxin, a selective antagonist of the gamma-aminobutyric acid (GABA)A receptor, did not modify toxin effects. We conclude that both toxins specifically block the postsynaptic glutamate receptor-channel complex.

Neuromuscular control of prey capture in frogs.

OpenAIRE

Nishikawa, K C

1999-01-01

While retaining a feeding apparatus that is surprisingly conservative morphologically, frogs as a group exhibit great variability in the biomechanics of tongue protraction during prey capture, which in turn is related to differences in neuromuscular control. In this paper, I address the following three questions. (1) How do frog tongues differ biomechanically? (2) What anatomical and physiological differences are responsible? (3) How is biomechanics related to mechanisms of neuromuscular cont...

Identification and Simulation as Tools for Measurement of Neuromuscular Properties

National Research Council Canada - National Science Library

Kearney, R

2001-01-01

Quantitative, objective methods for the evaluation of neuromuscular properties are required for the diagnosis of neuromuscular disorders and the evaluation of the effectiveness of treatment and rehabilitation...

Neuromuscular prehabilitation to prevent osteoarthritis after a traumatic joint injury.

Science.gov (United States)

Tenforde, Adam S; Shull, Pete B; Fredericson, Michael

2012-05-01

Post-traumatic osteoarthritis (PTOA) is a process resulting from direct forces applied to a joint that cause injury and degenerative changes. An estimated 12% of all symptomatic osteoarthritis (OA) of the hip, knee, and ankle can be attributed to a post-traumatic cause. Neuromuscular prehabilitation is the process of improving neuromuscular function to prevent development of PTOA after an initial traumatic joint injury. Prehabilitation strategies include restoration of normative movement patterns that have been altered as the result of traumatic injury, along with neuromuscular exercises and gait retraining to prevent the development of OA after an injury occurs. A review of the current literature shows that no studies have been performed to evaluate methods of neuromuscular prehabilitation to prevent PTOA after a joint injury. Instead, current research has focused on management strategies after knee injuries, the value of exercise in the management of OA, and neuromuscular exercises after total knee arthroplasty. Recent work in gait retraining that alters knee joint loading holds promise for preventing the development of PTOA after joint trauma. Future research should evaluate methods of neuromuscular prehabilitation strategies in relationship to the outcome of PTOA after joint injury. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Research highlights of partial neuromuscular disorders

Directory of Open Access Journals (Sweden)

Cheng ZHANG

2014-05-01

Full Text Available In order to understand the latest progression on neuromuscular disorders for clinicians, this review screened and systemized the papers on neuromuscular disorders which were collected by PubMed from January 2013 to February 2014. This review also introduced the clinical diagnosis and treatment hightlights on glycogen storage disease type Ⅱ (GSD Ⅱ, Duchenne muscular dystrophy (DMD, amyotrophic lateral sclerosis (ALS and spinal muscular atrophy (SMA. The important references will be useful for clinicians. doi: 10.3969/j.issn.1672-6731.2014.05.004

Design of block-copolymer-based micelles for active and passive targeting

NARCIS (Netherlands)

Lebouille, Jérôme G J L; Leermakers, Frans A M; Cohen Stuart, Martien A.; Tuinier, Remco

2016-01-01

A self-consistent field study is presented on the design of active and passive targeting block-copolymeric micelles. These micelles form in water by self-assembly of triblock copolymers with a hydrophilic middle block and two hydrophobic outer blocks. A minority amount of diblock copolymers with the

Design of block-copolymer-based micelles for active and passive targeting

NARCIS (Netherlands)

Lebouille, Jérôme G.J.L.; Leermakers, Frans A.M.; Cohen Stuart, Martien A.; Tuinier, Remco

2016-01-01

A self-consistent field study is presented on the design of active and passive targeting block-copolymeric micelles. These micelles form in water by self-assembly of triblock copolymers with a hydrophilic middle block and two hydrophobic outer blocks. A minority amount of diblock copolymers with

[Characteristics of neuromuscular scoliosis].

Science.gov (United States)

Putzier, M; Groß, C; Zahn, R K; Pumberger, M; Strube, P

2016-06-01

Usually, neuromuscular scolioses become clinically symptomatic relatively early and are rapidly progressive even after the end of growth. Without sufficient treatment they lead to a severe reduction of quality of life, to a loss of the ability of walking, standing or sitting as well as to an impairment of the cardiopulmonary system resulting in an increased mortality. Therefore, an intensive interdisciplinary treatment by physio- and ergotherapists, internists, pediatricians, orthotists, and orthopedists is indispensable. In contrast to idiopathic scoliosis the treatment of patients with neuromuscular scoliosis with orthosis is controversially discussed, whereas physiotherapy is established and essential to prevent contractures and to maintain the residual sensorimotor function.Frequently, the surgical treatment of the scoliosis is indicated. It should be noted that only long-segment posterior correction and fusion of the whole deformity leads to a significant improvement of the quality of life as well as to a prevention of a progression of the scoliosis and the development of junctional problems. The surgical intervention is usually performed before the end of growth. A prolonged delay of surgical intervention does not result in an increased height but only in a deformity progression and is therefore not justifiable. In early onset neuromuscular scolioses guided-growth implants are used to guarantee the adequat development. Because of the high complication rates, further optimization of these implant systems with regard to efficiency and safety have to be addressed in future research.

Neuromuscular compensation mechanisms in vocal fold paralysis and paresis.

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Dewan, Karuna; Vahabzadeh-Hagh, Andrew; Soofer, Donna; Chhetri, Dinesh K

2017-07-01

Vocal fold paresis and paralysis are common conditions. Treatment options include augmentation laryngoplasty and voice therapy. The optimal management for this condition is unclear. The objective of this study was to assess possible neuromuscular compensation mechanisms that could potentially be used in the treatment of vocal fold paresis and paralysis. In vivo canine model. In an in vivo canine model, we examined three conditions: 1) unilateral right recurrent laryngeal nerve (RLN) paresis and paralysis, 2) unilateral superior laryngeal nerve (SLN) paralysis, and 3) unilateral vagal nerve paresis and paralysis. Phonatory acoustics and aerodynamics were measured in each of these conditions. Effective compensation was defined as improved acoustic and aerodynamic profile. The most effective compensation for all conditions was increasing RLN activation and decreasing glottal gap. Increasing RLN activation increased the percentage of possible phonatory conditions that achieved phonation onset. SLN activation generally led to decreased number of total phonation onset conditions within each category. Differential effects of SLN (cricothyroid [CT] muscle) activation were seen. Ipsilateral SLN activation could compensate for RLN paralysis; normal CT compensated well in unilateral SLN paralysis; and in vagal paresis/paralysis, contralateral SLN and RLN displayed antagonistic relationships. Methods to improve glottal closure should be the primary treatment for large glottal gaps. Neuromuscular compensation is possible for paresis. This study provides insights into possible compensatory mechanisms in vocal fold paresis and paralysis. NA Laryngoscope, 127:1633-1638, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Neuromuscular ultrasound of cranial nerves.

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Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

2015-04-01

Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

Muscular power, neuromuscular activation, and performance in shot put athletes at preseason and at competition period.

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Kyriazis, Thomas A; Terzis, Gerasimos; Boudolos, Konstantinos; Georgiadis, Georgios

2009-09-01

The aim of this study was to investigate changes in shot put performance, muscular power, and neuromuscular activation of the lower extremities, between the preseason and the competition period, in skilled shot put athletes using the rotational technique. Shot put performance was assessed at the start of the pre-season period as well as after 12 weeks, at the competition period, in nine shot putters. Electromyographic (EMG) activity of the right vastus lateralis muscle was recorded during all shot put trials. Maximum squat strength (1RM) and mechanical parameters during the countermovement jump (CMJ) on a force platform were also determined at pre-season and at competition period. Shot put performance increased 4.7% (p phase was increased significantly (p training period. Shot put performance was significantly related with muscular power and takeoff velocity during the CMJ, at competition period (r = 0.66, p competition period.

Recent achievements in restorative neurology: Progressive neuromuscular diseases

International Nuclear Information System (INIS)

Dimitrijevic, M.R.; Kakulas, B.A.; Vrbova, G.

1986-01-01

This book contains 27 chapters. Some of the chapter titles are: Computed Tomography of Muscles in Neuromuscular Disease; Mapping the Genes for Muscular Dystrophy; Trophic Factors and Motor Neuron Development; Size of Motor Units and Firing Rate in Muscular Dystrophy; Restorative Possibilities in Relation to the Pathology of Progressive Neuromuscular Disease; and An Approach to the Pathogenesis of some Congenital Myopathies

Neuromuscular control of scapula muscles during a voluntary task in subjects with Subacromial Impingement Syndrome

DEFF Research Database (Denmark)

Larsen, C M; Søgaard, Karen; Chreiteh, S S

2013-01-01

and time to activity onset. In spite of a tendency to higher activity among SIS 0.10-0.30 between-group differences were not significant neither in ratio of muscle activation 0.80-0.98 nor time to activity onset 0.53-0.98. The hypothesized between-group differences in neuromuscular activity of Trapezius...

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

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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.

Altered knee joint neuromuscular control during landing from a jump in 10-15year old children with Generalised Joint Hypermobility. A substudy of the CHAMPS-study Denmark

DEFF Research Database (Denmark)

Junge, Tina; Wedderkopp, Niels; Thorlund, Jonas Bloch

2015-01-01

Generalised Joint Hypermobility (GJH) is considered an intrinsic risk factor for knee injuries. Knee neuromuscular control during landing may be altered in GJH due to reduced passive stability. The aim was to identify differences in knee neuromuscular control during landing of the Single...... than controls, all significant findings. Although the groups performed equally in SLHD, GJH had a Gastrocnemius Medialis dominated neuromuscular strategy before landing, plausibly caused by reduced Semitendinosus activity. Reduced Semitendinosus activity was seen in GJH after landing...

Motor unit recruitment during neuromuscular electrical stimulation: a critical appraisal.

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Bickel, C Scott; Gregory, Chris M; Dean, Jesse C

2011-10-01

Neuromuscular electrical stimulation (NMES) is commonly used in clinical settings to activate skeletal muscle in an effort to mimic voluntary contractions and enhance the rehabilitation of human skeletal muscles. It is also used as a tool in research to assess muscle performance and/or neuromuscular activation levels. However, there are fundamental differences between voluntary- and artificial-activation of motor units that need to be appreciated before NMES protocol design can be most effective. The unique effects of NMES have been attributed to several mechanisms, most notably, a reversal of the voluntary recruitment pattern that is known to occur during voluntary muscle contractions. This review outlines the assertion that electrical stimulation recruits motor units in a nonselective, spatially fixed, and temporally synchronous pattern. Additionally, it synthesizes the evidence that supports the contention that this recruitment pattern contributes to increased muscle fatigue when compared with voluntary actions and provides some commentary on the parameters of electrical stimulation as well as emerging technologies being developed to facilitate NMES implementation. A greater understanding of how electrical stimulation recruits motor units, as well as the benefits and limitations of its use, is highly relevant when using this tool for testing and training in rehabilitation, exercise, and/or research.

The relative frequency of common neuromuscular diagnoses in a reference center

OpenAIRE

Cotta, Ana; Paim, Júlia Filardi; Carvalho, Elmano; da-Cunha-Júnior, Antonio Lopes; Navarro, Monica M.; Valicek, Jaquelin; Menezes, Miriam Melo; Nunes, Simone Vilela; Xavier-Neto, Rafael; Baptista Junior, Sidney; Lima, Luciano Romero; Takata, Reinaldo Issao; Vargas, Antonio Pedro

2017-01-01

ABSTRACT The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. Objective: To report the relative frequency of common neuromuscular diagnoses in a reference center. Methods: A 17-year chart review of patients with suspicion of myopathy. Results: Among 3,412 examinations, 1,603 (46.98%) yielded confir...

Quantitative determination of biological activity of botulinum toxins utilizing compound muscle action potentials (CMAP), and comparison of neuromuscular transmission blockage and muscle flaccidity among toxins.

Science.gov (United States)

Torii, Yasushi; Goto, Yoshitaka; Takahashi, Motohide; Ishida, Setsuji; Harakawa, Tetsuhiro; Sakamoto, Takashi; Kaji, Ryuji; Kozaki, Shunji; Ginnaga, Akihiro

2010-01-01

The biological activity of various types of botulinum toxin has been evaluated using the mouse intraperitoneal LD(50) test (ip LD(50)). This method requires a large number of mice to precisely determine toxin activity, and so has posed a problem with regard to animal welfare. We have used a direct measure of neuromuscular transmission, the compound muscle action potential (CMAP), to evaluate the effect of different types of botulinum neurotoxin (NTX), and we compared the effects of these toxins to evaluate muscle relaxation by employing the digit abduction scoring (DAS) assay. This method can be used to measure a broad range of toxin activities the day after administration. Types A, C, C/D, and E NTX reduced the CMAP amplitude one day after administration at below 1 ip LD(50), an effect that cannot be detected using the mouse ip LD(50) assay. The method is useful not only for measuring toxin activity, but also for evaluating the characteristics of different types of NTX. The rat CMAP test is straightforward, highly reproducible, and can directly determine the efficacy of toxin preparations through their inhibition of neuromuscular transmission. Thus, this method may be suitable for pharmacology studies and the quality control of toxin preparations. Copyright 2009 Elsevier Ltd. All rights reserved.

Effects of Short- and Long-Duration Space Flight on Neuromuscular Function

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Buxton, Roxanne E.; Spiering, Barry A.; Ryder, Jeffrey W.; Ploutz-Snyder, Lori L.; Bloomberg, Jacob J.

2010-01-01

The Functional Task Tests (FTT) is an interdisciplinary study designed to correlate the changes in functional tasks (such as emergency egress, ladder climbing, and hatch opening) with changes in neuromuscular, cardiovascular, and sensorimotor function. One aspect of the FTT, the neuromuscular function test, is used to investigate the neuromuscular component underlying changes in the ability of astronauts to perform functional tasks (representative of critical mission tasks) safely and quickly after flight. PURPOSE: To describe neuromuscular function after short- and long-duration space flight. METHODS: To date, 5 crewmembers on short-duration (10- to 15-day) missions and 3 on long-duration missions have participated. Crewmembers were assessed 30 days before flight, on landing day (short-duration subjects only) and 1, 6, and 30 days after landing. The interpolated twitch technique, which utilizes a combination of maximal voluntary contractions and electrically evoked contractions, was used to assess the maximal voluntary isometric force (MIF) and central activation capacity of the knee extensors. Leg-press and bench-press devices were used to assess MIF and maximal dynamic power of the lower and upper body respectively. Specifically, power was measured during concentric-only ballistic throws of the leg-press sled and bench-press bar loaded to 40% and 30% of MIF respectively. RESULTS: Data are currently being collected from both Shuttle and ISS crewmembers. Emerging data indicate that measures of knee extensor muscle function are decreased with long-duration flight. DISCUSSION: The relationships between flight duration, neural drive, and muscle performance are of particular interest. Ongoing research will add to the current sample size and will focus on defining changes in muscle performance measures after long-duration space flight.

Muscle Expression of SOD1G93A Triggers the Dismantlement of Neuromuscular Junction via PKC-Theta.

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Dobrowolny, Gabriella; Martini, Martina; Scicchitano, Bianca Maria; Romanello, Vanina; Boncompagni, Simona; Nicoletti, Carmine; Pietrangelo, Laura; De Panfilis, Simone; Catizone, Angela; Bouchè, Marina; Sandri, Marco; Rudolf, Rüdiger; Protasi, Feliciano; Musarò, Antonio

2018-04-20

Neuromuscular junction (NMJ) represents the morphofunctional interface between muscle and nerve. Several chronic pathologies such as aging and neurodegenerative diseases, including muscular dystrophy and amyotrophic lateral sclerosis, display altered NMJ and functional denervation. However, the triggers and the molecular mechanisms underlying the dismantlement of NMJ remain unclear. Here we provide evidence that perturbation in redox signaling cascades, induced by muscle-specific accumulation of mutant SOD1 G93A in transgenic MLC/SOD1 G93A mice, is causally linked to morphological alterations of the neuromuscular presynaptic terminals, high turnover rate of acetylcholine receptor, and NMJ dismantlement. The analysis of potential molecular mechanisms that mediate the toxic activity of SOD1 G93A revealed a causal link between protein kinase Cθ (PKCθ) activation and NMJ disintegration. The study discloses the molecular mechanism that triggers functional denervation associated with the toxic activity of muscle SOD1 G93A expression and suggests the possibility of developing a new strategy to counteract age- and pathology-associated denervation based on pharmacological inhibition of PKCθ activity. Collectively, these data indicate that muscle-specific accumulation of oxidative damage can affect neuromuscular communication and induce NMJ dismantlement through a PKCθ-dependent mechanism. Antioxid. Redox Signal. 28, 1105-1119.

Acute Neuromuscular Adaptations in the Postural Control of Patients with Parkinson’s Disease after Perturbed Walking

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Cristian F. Pasluosta

2017-09-01

Full Text Available Patients suffering from Parkinson’s disease (PD present motor impairments reflected in the dynamics of the center of pressure (CoP adjustments during quiet standing. One method to study the dynamics of CoP adjustments is the entropic half-life (EnHL, which measures the short-term correlations of a time series at different time scales. Changes in the EnHL of CoP time series suggest neuromuscular adaptations in the control of posture. In this study, we sought to investigate the immediate changes in the EnHL of CoP adjustments of patients with PD during one session of perturbed (experimental group and unperturbed treadmill walking (control group. A total of 39 patients with PD participated in this study. The experimental group (n = 19 walked on a treadmill providing small tilting of the treadmill platform. The control group (n = 20 walked without perturbations. Each participant performed 5-min practice followed by three 5-min training blocks of walking with or without perturbation (with 3-min resting in between. Quiet standing CoP data was collected for 30 s at pre-training, after each training block, immediately post-training, and after 10 min retention. The EnHL was computed on the original and surrogates (phase-randomized CoP signals in the medio-lateral (ML and anterior–posterior (AP directions. Data was analyzed using four-way mixed ANOVA. Increased EnHL values were observed for both groups (Time effect, p < 0.001 as the intervention progressed, suggesting neuromuscular adaptations in the control of posture. The EnHL of surrogate signals were significantly lower than for original signals (p < 0.001, confirming that these adaptations come from non-random control processes. There was no Group effect (p = 0.622, however by analyzing the significant Group by Direction by Time interaction (p < 0.05, a more pronounced effect in the ML direction of the perturbed group was observed. Altogether, our findings show that treadmill walking decreases

Neuromuscular Bandage: Neurophysiological Effects and the Role of Fascias

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Ximena María Villota Chicaíza

2014-05-01

Full Text Available During the last years, neuromuscular bandage, a therapeutic application created in 1979 by doctor Kenzo Kase has been introduced in the management of many disorders of the musculo-skeletal system and even more so in the treatment of neurological disorders; This therapeutic tool which consists of a self adhesive elastic bandage allows recovery of the injured party without diminishing its bodily function. According to the existing literature on the physiological effects of this therapeutic application in the body, you could say that there is consensus. However in this article the author wants to highlight the significant although little highlighted role played by the fas¬cias on the therapeutic effects of neuromuscular bandage, analyzing from a reflective perspective the analgesic, neuromechanical and circulatory effects, as fundamental effects of neuromuscular bandage and fascias in the same function, trying to bring a global understanding on the way they relate to all connective tissues, aspects that are of great importance for the proper evaluation of alterations and prescription of neuromuscular bandage

Imaging of respiratory muscles in neuromuscular disease: A review.

Science.gov (United States)

Harlaar, L; Ciet, P; van der Ploeg, A T; Brusse, E; van der Beek, N A M E; Wielopolski, P A; de Bruijne, M; Tiddens, H A W M; van Doorn, P A

2018-03-01

Respiratory muscle weakness frequently occurs in patients with neuromuscular disease. Measuring respiratory function with standard pulmonary function tests provides information about the contribution of all respiratory muscles, the lungs and airways. Imaging potentially enables the study of different respiratory muscles, including the diaphragm, separately. In this review, we provide an overview of imaging techniques used to study respiratory muscles in neuromuscular disease. We identified 26 studies which included a total of 573 patients with neuromuscular disease. Imaging of respiratory muscles was divided into static and dynamic techniques. Static techniques comprise chest radiography, B-mode (brightness mode) ultrasound, CT and MRI, and are used to assess the position and thickness of the diaphragm and the other respiratory muscles. Dynamic techniques include fluoroscopy, M-mode (motion mode) ultrasound and MRI, used to assess diaphragm motion in one or more directions. We discuss how these imaging techniques relate with spirometric values and whether these can be used to study the contribution of the different respiratory muscles in patients with neuromuscular disease. Copyright © 2017. Published by Elsevier B.V.

Total hip arthroplasty in patients with neuromuscular imbalance.

Science.gov (United States)

Konan, S; Duncan, C P

2018-01-01

Patients with neuromuscular imbalance who require total hip arthroplasty (THA) present particular technical problems due to altered anatomy, abnormal bone stock, muscular imbalance and problems of rehabilitation. In this systematic review, we studied articles dealing with THA in patients with neuromuscular imbalance, published before April 2017. We recorded the demographics of the patients and the type of neuromuscular pathology, the indication for surgery, surgical approach, concomitant soft-tissue releases, the type of implant and bearing, pain and functional outcome as well as complications and survival. Recent advances in THA technology allow for successful outcomes in these patients. Our review suggests excellent benefits for pain relief and good functional outcome might be expected with a modest risk of complication. Cite this article: Bone Joint J 2018;100-B(1 Supple A):17-21. ©2018 The British Editorial Society of Bone & Joint Surgery.

Altered knee joint neuromuscular control during landing from a jump in 10-15 year old children with generalised joint hypermobility. A substudy of the CHAMPS-study Denmark

DEFF Research Database (Denmark)

Junge, Tina; Juul-Kristensen, B; Bloch Thorlund, Jonas

Generalised Joint Hypermobility (GJH) is considered an intrinsic risk factor for knee injuries. Knee neuromuscular control during landing may be altered in GJH due to reduced passive stability. The aim was to identify differences in knee neuromuscular control during landing of the Single...... Electrical activity (MVE). There was no difference in jump length between groups. Before landing, GJH had 33% lower Semitendinosus, but 32% higher Gastrocnemius Medialis activity and 39% higher co-contraction of the lateral knee muscles, than controls. After landing, GJH had 36% lower Semitendinosus activity...... than controls, all significant findings. Although the groups performed equally in SLHD, GJH had a Gastrocnemius Medialis-dominated neuromuscular strategy before landing, plausibly caused by reduced Semitendinosus activity. Reduced Semitendinosus activity was seen in GJH after landing...

The novel protein kinase C epsilon isoform modulates acetylcholine release in the rat neuromuscular junction.

Science.gov (United States)

Obis, Teresa; Hurtado, Erica; Nadal, Laura; Tomàs, Marta; Priego, Mercedes; Simon, Anna; Garcia, Neus; Santafe, Manel M; Lanuza, Maria A; Tomàs, Josep

2015-12-01

Various protein kinase C (PKC) isoforms contribute to the phosphorylating activity that modulates neurotransmitter release. In previous studies we showed that nPKCε is confined in the presynaptic site of the neuromuscular junction and its presynaptic function is activity-dependent. Furthermore, nPKCε regulates phorbol ester-induced acetylcholine release potentiation, which further indicates that nPKCε is involved in neurotransmission. The present study is designed to examine the nPKCε involvement in transmitter release at the neuromuscular junction. We use the specific nPKCε translocation inhibitor peptide εV1-2 and electrophysiological experiments to investigate the involvement of this isoform in acetylcholine release. We observed that nPKCε membrane translocation is key to the synaptic potentiation of NMJ, being involved in several conditions that upregulate PKC isoforms coupling to acetylcholine (ACh) release (incubation with high Ca(2+), stimulation with phorbol esters and protein kinase A, stimulation with adenosine 3',5'-cyclic monophosphorothioate, 8-Bromo-, Rp-isomer, sodium salt -Sp-8-BrcAMP-). In all these conditions, preincubation with the nPKCε translocation inhibitor peptide (εV1-2) impairs PKC coupling to acetylcholine release potentiation. In addition, the inhibition of nPKCε translocation and therefore its activity impedes that presynaptic muscarinic autoreceptors and adenosine autoreceptors modulate transmitter secretion. Together, these results point to the importance of nPKCε isoform in the control of acetylcholine release in the neuromuscular junction.

Synaptic defects in the spinal and neuromuscular circuitry in a mouse model of spinal muscular atrophy.

Directory of Open Access Journals (Sweden)

Karen K Y Ling

2010-11-01

Full Text Available Spinal muscular atrophy (SMA is a major genetic cause of death in childhood characterized by marked muscle weakness. To investigate mechanisms underlying motor impairment in SMA, we examined the spinal and neuromuscular circuitry governing hindlimb ambulatory behavior in SMA model mice (SMNΔ7. In the neuromuscular circuitry, we found that nearly all neuromuscular junctions (NMJs in hindlimb muscles of SMNΔ7 mice remained fully innervated at the disease end stage and were capable of eliciting muscle contraction, despite a modest reduction in quantal content. In the spinal circuitry, we observed a ∼28% loss of synapses onto spinal motoneurons in the lateral column of lumbar segments 3-5, and a significant reduction in proprioceptive sensory neurons, which may contribute to the 50% reduction in vesicular glutamate transporter 1(VGLUT1-positive synapses onto SMNΔ7 motoneurons. In addition, there was an increase in the association of activated microglia with SMNΔ7 motoneurons. Together, our results present a novel concept that synaptic defects occur at multiple levels of the spinal and neuromuscular circuitry in SMNΔ7 mice, and that proprioceptive spinal synapses could be a potential target for SMA therapy.

Neuromuscular blockade of slow twitch muscle fibres elevates muscle oxygen uptake and energy turnover during submaximal exercise in humans.

Science.gov (United States)

Krustrup, Peter; Secher, Niels H; Relu, Mihai U; Hellsten, Ylva; Söderlund, Karin; Bangsbo, Jens

2008-12-15

We tested the hypothesis that a greater activation of fast-twitch (FT) fibres during dynamic exercise leads to a higher muscle oxygen uptake (VO2 ) and energy turnover as well as a slower muscle on-kinetics. Subjects performed one-legged knee-extensor exercise for 10 min at an intensity of 30 W without (CON) and with (CUR) arterial injections of the non-depolarizing neuromuscular blocking agent cisatracurium. In CUR, creatine phosphate (CP) was unaltered in slow twitch (ST) fibres and decreased (P fibres, whereas in CON, CP decreased (P fibres, respectively. From 127 s of exercise, muscle VO2 was higher (P muscle VO2 response was slower (P muscle homogenate CP was lowered (P muscle lactate production was similar in CUR and CON (37.8 +/- 4.1 versus 35.2 +/- 6.2 mmol). Estimated total muscle ATP turnover was 19% higher (P fibres are less efficient than ST fibres in vivo at a contraction frequency of 1 Hz, and that the muscle VO2 kinetics is slowed by FT fibre activation.

Effects of Different Footwear Properties and Surface Instability on Neuromuscular Activity and Kinematics During Jumping.

Science.gov (United States)

Lesinski, Melanie; Prieske, Olaf; Borde, Ron; Beurskens, Rainer; Granacher, Urs

2018-04-13

Lesinski, M, Prieske, O, Borde, R, Beurskens, R, and Granacher, U. Effects of different footwear properties and surface instability on neuromuscular activity and kinematics during jumping. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this study was to examine sex-specific effects of different footwear properties vs. barefoot condition during the performance of drop jumps (DJs) on stable and unstable surfaces on measures of jump performance, electromyographic (EMG) activity, and knee joint kinematics. Drop jump performance, EMG activity of lower-extremity muscles, as well as sagittal and frontal knee joint kinematics were tested in 28 healthy male (n = 14) and female (n = 14) physically active sports science students (23 ± 2 years) during the performance of DJs on stable and unstable surfaces using different footwear properties (elastic vs. minimal shoes) vs. barefoot condition. Analysis revealed a significantly lower jump height and performance index (Δ7-12%; p footwear conditions (Δ29%; p footwear-surface interactions were detected. Our findings revealed that surface instability had an impact on DJ performance, thigh/shank muscle activity, and knee joint kinematics. In addition, the single factors "footwear" and "sex" modulated knee joint kinematics during DJs. However, hardly any significant interaction effects were found. Thus, additional footwear-related effects can be neglected when performing DJs during training on different surfaces.

An 8-Week Neuromuscular Exercise Program for Patients With Mild to Moderate Knee Osteoarthritis

DEFF Research Database (Denmark)

Clausen, Brian; Holsgaard-Larsen, Anders; Roos, Ewa M

2017-01-01

OBJECTIVE:   To describe the feasibility of a neuromuscular exercise (NEMEX) program in patients with mild to moderate knee osteoarthritis (KOA). BACKGROUND:   Neuromuscular exercise has been increasingly used in patients with osteoarthritis to achieve sensorimotor control and improved daily...... function. TREATMENT:   A study of the first 23 physically active patients (11 men, 12 women; age range = 48-70 years) who had mild to moderate KOA and were undergoing an 8-week, twice-weekly program, consisting of 11 exercises with 3 to 4 levels of difficulty, as part of an ongoing randomized controlled...... to increased (n = 2) or persisting (n = 1) knee pain. However, their pain ratings did not show worsening symptoms. UNIQUENESS:   This NEMEX-KOA program was designed for physically active middle-aged patients with mild to moderate KOA; therefore, it involved exercises and difficulty levels that were more...

Synaptic Activity and Muscle Contraction Increases PDK1 and PKCβI Phosphorylation in the Presynaptic Membrane of the Neuromuscular Junction

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Erica Hurtado

2017-08-01

Full Text Available Conventional protein kinase C βI (cPKCβI is a conventional protein kinase C (PKC isoform directly involved in the regulation of neurotransmitter release in the neuromuscular junction (NMJ. It is located exclusively at the nerve terminal and both synaptic activity and muscle contraction modulate its protein levels and phosphorylation. cPKCβI molecular maturation includes a series of phosphorylation steps, the first of which is mediated by phosphoinositide-dependent kinase 1 (PDK1. Here, we sought to localize PDK1 in the NMJ and investigate the hypothesis that synaptic activity and muscle contraction regulate in parallel PDK1 and cPKCβI phosphorylation in the membrane fraction. To differentiate the presynaptic and postsynaptic activities, we abolished muscle contraction with μ-conotoxin GIIIB (μ-CgTx-GIIIB in some experiments before stimulation of the phrenic nerve (1 Hz, 30 min. Then, we analyzed total and membrane/cytosol fractions of skeletal muscle by Western blotting. Results showed that PDK1 is located exclusively in the nerve terminal of the NMJ. After nerve stimulation with and without coincident muscle contraction, total PDK1 and phosphorylated PDK1 (pPDK1 protein levels remained unaltered. However, synaptic activity specifically enhanced phosphorylation of PDK1 in the membrane, an important subcellular location for PDK1 function. This increase in pPDK1 coincides with a significant increase in the phosphorylation of its substrate cPKCβI also in the membrane fraction. Moreover, muscle contraction maintains PDK1 and pPDK1 but increases cPKCβI protein levels and its phosphorylation. Thus, even though PDK1 activity is maintained, pcPKCβI levels increase in concordance with total cPKCβI. Together, these results indicate that neuromuscular activity could induce the membrane targeting of pPDK1 in the nerve terminal of the NMJ to promote the phosphorylation of the cPKCβI, which is involved in ACh release.

Synaptic Activity and Muscle Contraction Increases PDK1 and PKCβI Phosphorylation in the Presynaptic Membrane of the Neuromuscular Junction.

Science.gov (United States)

Hurtado, Erica; Cilleros, Víctor; Just, Laia; Simó, Anna; Nadal, Laura; Tomàs, Marta; Garcia, Neus; Lanuza, Maria A; Tomàs, Josep

2017-01-01

Conventional protein kinase C βI (cPKCβI) is a conventional protein kinase C (PKC) isoform directly involved in the regulation of neurotransmitter release in the neuromuscular junction (NMJ). It is located exclusively at the nerve terminal and both synaptic activity and muscle contraction modulate its protein levels and phosphorylation. cPKCβI molecular maturation includes a series of phosphorylation steps, the first of which is mediated by phosphoinositide-dependent kinase 1 (PDK1). Here, we sought to localize PDK1 in the NMJ and investigate the hypothesis that synaptic activity and muscle contraction regulate in parallel PDK1 and cPKCβI phosphorylation in the membrane fraction. To differentiate the presynaptic and postsynaptic activities, we abolished muscle contraction with μ-conotoxin GIIIB (μ-CgTx-GIIIB) in some experiments before stimulation of the phrenic nerve (1 Hz, 30 min). Then, we analyzed total and membrane/cytosol fractions of skeletal muscle by Western blotting. Results showed that PDK1 is located exclusively in the nerve terminal of the NMJ. After nerve stimulation with and without coincident muscle contraction, total PDK1 and phosphorylated PDK1 (pPDK1) protein levels remained unaltered. However, synaptic activity specifically enhanced phosphorylation of PDK1 in the membrane, an important subcellular location for PDK1 function. This increase in pPDK1 coincides with a significant increase in the phosphorylation of its substrate cPKCβI also in the membrane fraction. Moreover, muscle contraction maintains PDK1 and pPDK1 but increases cPKCβI protein levels and its phosphorylation. Thus, even though PDK1 activity is maintained, pcPKCβI levels increase in concordance with total cPKCβI. Together, these results indicate that neuromuscular activity could induce the membrane targeting of pPDK1 in the nerve terminal of the NMJ to promote the phosphorylation of the cPKCβI, which is involved in ACh release.

Silver-enhanced block copolymer membranes with biocidal activity

KAUST Repository

Madhavan, Poornima

2014-11-12

Silver nanoparticles were deposited on the surface and pore walls of block copolymer membranes with highly ordered pore structure. Pyridine blocks constitute the pore surfaces, complexing silver ions and promoting a homogeneous distribution. Nanoparticles were then formed by reduction with sodium borohydride. The morphology varied with the preparation conditions (pH and silver ion concentration), as confirmed by field emission scanning and transmission electron microscopy. Silver has a strong biocide activity, which for membranes can bring the advantage of minimizing the growth of bacteria and formation of biofilm. The membranes with nanoparticles prepared under different pH values and ion concentrations were incubated with Pseudomonas aeruginosa and compared with the control. The strongest biocidal activity was achieved with membranes containing membranes prepared under pH 9. Under these conditions, the best distribution with small particle size was observed by microscopy.

Silver-enhanced block copolymer membranes with biocidal activity

KAUST Repository

Madhavan, Poornima; Hong, Pei-Ying; Sougrat, Rachid; Nunes, Suzana Pereira

2014-01-01

Silver nanoparticles were deposited on the surface and pore walls of block copolymer membranes with highly ordered pore structure. Pyridine blocks constitute the pore surfaces, complexing silver ions and promoting a homogeneous distribution. Nanoparticles were then formed by reduction with sodium borohydride. The morphology varied with the preparation conditions (pH and silver ion concentration), as confirmed by field emission scanning and transmission electron microscopy. Silver has a strong biocide activity, which for membranes can bring the advantage of minimizing the growth of bacteria and formation of biofilm. The membranes with nanoparticles prepared under different pH values and ion concentrations were incubated with Pseudomonas aeruginosa and compared with the control. The strongest biocidal activity was achieved with membranes containing membranes prepared under pH 9. Under these conditions, the best distribution with small particle size was observed by microscopy.

The role of proprioception and neuromuscular stability in carpal instabilities.

Science.gov (United States)

Hagert, E; Lluch, A; Rein, S

2016-01-01

Carpal stability has traditionally been defined as dependent on the articular congruity of joint surfaces, the static stability maintained by intact ligaments, and the dynamic stability caused by muscle contractions resulting in a compression of joint surfaces. In the past decade, a fourth factor in carpal stability has been proposed, involving the neuromuscular and proprioceptive control of joints. The proprioception of the wrist originates from afferent signals elicited by sensory end organs (mechanoreceptors) in ligaments and joint capsules that elicit spinal reflexes for immediate joint stability, as well as higher order neuromuscular influx to the cerebellum and sensorimotor cortices for planning and executing joint control. The aim of this review is to provide an understanding of the role of proprioception and neuromuscular control in carpal instabilities by delineating the sensory innervation and the neuromuscular control of the carpus, as well as descriptions of clinical applications of proprioception in carpal instabilities. © The Author(s) 2015.

Effects of HRV-Guided vs. Predetermined Block Training on Performance, HRV and Serum Hormones.

Science.gov (United States)

Nuuttila, Olli-Pekka; Nikander, Aku; Polomoshnov, Dmitry; Laukkanen, Jari Antero; Häkkinen, Keijo

2017-11-01

The aim of this study was to compare heart rate variability -guided (HRVG) and predetermined (PD) block periodization of high intensity aerobic training (HIT). Endurance performance, neuromuscular performance, heart rate variability (HRV) and serum hormone concentrations were measured before, in the middle and after the 8-week training period in 24 endurance trained males. Both groups improved significantly maximal treadmill velocity (V max ) (pHRV (RMSSD, LF and TP) increased significantly only in HRVG (pHRV and serum testosterone levels observed in HRVG, individually HRV -guided block training may be more optimal compared to predetermined training. © Georg Thieme Verlag KG Stuttgart · New York.

The Effect of Different Repeated-High-Intensity-Effort Bouts on Subsequent Running, Skill Performance, and Neuromuscular Function.

Science.gov (United States)

Johnston, Rich D; Gabbett, Tim J; Jenkins, David G; Speranza, Michael J

2016-04-01

To assess the impact of different repeated-high-intensity-effort (RHIE) bouts on player activity profiles, skill involvements, and neuromuscular fatigue during small-sided games. 22 semiprofessional rugby league players (age 24.0 ± 1.8 y, body mass 95.6 ± 7.4 kg). During 4 testing sessions, they performed RHIE bouts that each differed in the combination of contact and running efforts, followed by a 5-min off-side small-sided game before performing a second bout of RHIE activity and another 5-min small-sided game. Global positioning system microtechnology and video recordings provided information on activity profiles and skill involvements. A countermovement jump and a plyometric push-up assessed changes in lower- and upper-body neuromuscular function after each session. After running-dominant RHIE bouts, players maintained running intensities during both games. In the contact-dominant RHIE bouts, reductions in moderate-speed activity were observed from game 1 to game 2 (ES = -0.71 to -1.06). There was also moderately lower disposal efficiency across both games after contact-dominant RHIE activity compared with running-dominant activity (ES = 0.62-1.02). Greater reductions in lower-body fatigue occurred as RHIE bouts became more running dominant (ES = -0.01 to -1.36), whereas upper-body fatigue increased as RHIE bouts became more contact dominant (ES = -0.07 to -1.55). Physical contact causes reductions in running intensity and the quality of skill involvements during game-based activities. In addition, the neuromuscular fatigue experienced by players is specific to the activities performed.

Efficacy of tricaine methanesulfonate (MS-222 as an anesthetic agent for blocking sensory-motor responses in Xenopus laevis tadpoles.

Directory of Open Access Journals (Sweden)

Carlana Ramlochansingh

Full Text Available Anesthetics are drugs that reversibly relieve pain, decrease body movements and suppress neuronal activity. Most drugs only cover one of these effects; for instance, analgesics relieve pain but fail to block primary fiber responses to noxious stimuli. Alternately, paralytic drugs block synaptic transmission at neuromuscular junctions, thereby effectively paralyzing skeletal muscles. Thus, both analgesics and paralytics each accomplish one effect, but fail to singularly account for all three. Tricaine methanesulfonate (MS-222 is structurally similar to benzocaine, a typical anesthetic for anamniote vertebrates, but contains a sulfate moiety rendering this drug more hydrophilic. MS-222 is used as anesthetic in poikilothermic animals such as fish and amphibians. However, it is often argued that MS-222 is only a hypnotic drug and its ability to block neural activity has been questioned. This prompted us to evaluate the potency and dynamics of MS-222-induced effects on neuronal firing of sensory and motor nerves alongside a defined motor behavior in semi-intact in vitro preparations of Xenopus laevis tadpoles. Electrophysiological recordings of extraocular motor discharge and both spontaneous and evoked mechanosensory nerve activity were measured before, during and after administration of MS-222, then compared to benzocaine and a known paralytic, pancuronium. Both MS-222 and benzocaine, but not pancuronium caused a dose-dependent, reversible blockade of extraocular motor and sensory nerve activity. These results indicate that MS-222 as benzocaine blocks the activity of both sensory and motor nerves compatible with the mechanistic action of effective anesthetics, indicating that both caine-derivates are effective as single-drug anesthetics for surgical interventions in anamniotes.

Reversal of rocuronium-induced neuromuscular blockade by sugammadex allows for optimization of neural monitoring of the recurrent laryngeal nerve.

Science.gov (United States)

Lu, I-Cheng; Wu, Che-Wei; Chang, Pi-Ying; Chen, Hsiu-Ya; Tseng, Kuang-Yi; Randolph, Gregory W; Cheng, Kuang-I; Chiang, Feng-Yu

2016-04-01

The use of neuromuscular blocking agent may effect intraoperative neuromonitoring (IONM) during thyroid surgery. An enhanced neuromuscular-blockade (NMB) recovery protocol was investigated in a porcine model and subsequently clinically applied during human thyroid neural monitoring surgery. Prospective animal and retrospective clinical study. In the animal experiment, 12 piglets were injected with rocuronium 0.6 mg/kg and randomly allocated to receive normal saline, sugammadex 2 mg/kg, or sugammadex 4 mg/kg to compare the recovery of laryngeal electromyography (EMG). In a subsequent clinical application study, 50 patients who underwent thyroidectomy with IONM followed an enhanced NMB recovery protocol-rocuronium 0.6 mg/kg at anesthesia induction and sugammadex 2 mg/kg at the operation start. The train-of-four (TOF) ratio was used for continuous quantitative monitoring of neuromuscular transmission. In our porcine model, it took 49 ± 15, 13.2 ± 5.6, and 4.2 ± 1.5 minutes for the 80% recovery of laryngeal EMG after injection of saline, sugammadex 2 mg/kg, and sugammadex 4 mg/kg, respectively. In subsequent clinical human application, the TOF ratio recovered from 0 to >0.9 within 5 minutes after administration of sugammadex 2 mg/kg at the operation start. All patients had positive and high EMG amplitude at the early stage of the operation, and intubation was without difficulty in 96% of patients. Both porcine modeling and clinical human application demonstrated that sugammadex 2 mg/kg allows effective and rapid restoration of neuromuscular function suppressed by rocuronium. Implementation of this enhanced NMB recovery protocol assures optimal conditions for tracheal intubation as well as IONM in thyroid surgery. NA. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Palliative care in neuromuscular diseases

NARCIS (Netherlands)

de Visser, Marianne; Oliver, David J.

2017-01-01

Purpose of review Palliative care is an approach that improves the quality of life of patients and their families facing the problem associated with life-threatening illness. Neuromuscular disorders (NMDs) are characterized by progressive muscle weakness, leading to pronounced and incapacitating

Effects of novel tubing gait on neuromuscular imbalance in cerebral palsy.

Science.gov (United States)

Shin, Yoon Kyum; Lee, Dong Ryul; Kim, Do Hyun; Lee, Jae Jin; You, Sung Joshua Hyun; Yi, Chung Hwi; Jeon, Hye Seon

2014-01-01

Gait impairments from a neuromuscular imbalance are crucial issues in cerebral palsy. The purpose of our study was to compare the effects of the assistive tubing gait (ATG) and assistive-resistive tubing gait (ARTG) on improving the vasti and hamstring muscle imbalance during the initial contact to mid-stance phases in individuals with spastic diplegic cerebral palsy (CP). Fourteen age-matched individuals including seven normal individuals (11.7 years) and seven individuals with CP (12.9 years) were recruited. All participants underwent electromyography (EMG) measurement of the unilateral vasti and hamstring muscle activity during the three gait training conditions of no-tubing gait (NTG), ATG, and ARTG. A statistical one-way repeated-measure analysis of variance (ANOVA) was used to determine differences in the vasti and hamstring activity, the vasti/hamstring ratio, and the knee joint angle across the three gait training conditions for each group. The initial vasti and hamstring muscle imbalance in CP was significantly improved by applying the ARTG compared with the ATG. The vasti/hamstring ratio during the ARTG was compatible with the ratio value obtained from the NTG of normal individuals. The knee joint angle in CP was not improved in this short-term intervention. The ARTG proportionately increased the vasti activation and reciprocally inhibited the hamstring activity, subsequently improving the neuromuscular imbalance associated with the flexed-knee gait in individuals with spastic diplegic CP.

Surgical Space Conditions During Low-Pressure Laparoscopic Cholecystectomy with Deep Versus Moderate Neuromuscular Blockade

DEFF Research Database (Denmark)

Staehr-Rye, Anne K; Rasmussen, Lars S.; Rosenberg, Jacob

2014-01-01

: In this assessor-blinded study, 48 patients undergoing elective laparoscopic cholecystectomy were administered rocuronium for neuromuscular blockade and randomized to either deep neuromuscular blockade (rocuronium bolus plus infusion maintaining a posttetanic count 0-1) or moderate neuromuscular blockade...... (rocuronium repeat bolus only for inadequate surgical conditions with spontaneous recovery of neuromuscular function). Patients received anesthesia with propofol, remifentanil, and rocuronium. The primary outcome was the proportion of procedures with optimal surgical space conditions (assessed by the surgeon...

Muscle synergies and complexity of neuromuscular control during gait in cerebral palsy.

Science.gov (United States)

Steele, Katherine M; Rozumalski, Adam; Schwartz, Michael H

2015-12-01

Individuals with cerebral palsy (CP) have impaired movement due to a brain injury near birth. Understanding how neuromuscular control is altered in CP can provide insight into pathological movement. We sought to determine if individuals with CP demonstrate reduced complexity of neuromuscular control during gait compared with unimpaired individuals and if changes in control are related to functional ability. Muscle synergies during gait were retrospectively analyzed for 633 individuals (age range 3.9-70y): 549 with CP (hemiplegia, n=122; diplegia, n=266; triplegia, n=73; quadriplegia, n=88) and 84 unimpaired individuals. Synergies were calculated using non-negative matrix factorization from surface electromyography collected during previous clinical gait analyses. Synergy complexity during gait was compared with diagnosis subtype, functional ability, and clinical examination measures. Fewer synergies were required to describe muscle activity during gait in individuals with CP compared with unimpaired individuals. Changes in synergies were related to functional impairment and clinical examination measures including selective motor control, strength, and spasticity. Individuals with CP use a simplified control strategy during gait compared with unimpaired individuals. These results were similar to synergies during walking among adult stroke survivors, suggesting similar neuromuscular control strategies between these clinical populations. © 2015 Mac Keith Press.

Neuromuscular exercise as treatment of degenerative knee disease

DEFF Research Database (Denmark)

Ageberg, Eva; Roos, Ewa M.

2015-01-01

Exercise is recommended as first-line treatment of degenerative knee disease. Our hypothesis is that neuromuscular exercise is feasible and at least as effective as tradionally used strength or aerobic training, but aims to more closely target the sensorimotor deficiencies and functional...... instability associated with the degenerative knee disease than traditionally used training methods.SUMMARY FOR TABLE OF CONTENTS PAGECurrent data suggests that the effect from neuromuscular exercise on pain and function is comparable to the effects seen from other forms of exercise....

Hippocampal activation during face-name associative memory encoding: blocked versus permuted design

International Nuclear Information System (INIS)

De Vogelaere, Frederick; Vingerhoets, Guy; Santens, Patrick; Boon, Paul; Achten, Erik

2010-01-01

The contribution of the hippocampal subregions to episodic memory through the formation of new associations between previously unrelated items such as faces and names is established but remains under discussion. Block design studies in this area of research generally tend to show posterior hippocampal activation during encoding of novel associational material while event-related studies emphasize anterior hippocampal involvement. We used functional magnetic resonance imaging to assess the involvement of anterior and posterior hippocampus in the encoding of novel associational material compared to the viewing of previously seen associational material. We used two different experimental designs, a block design and a permuted block design, and applied it to the same associative memory task to perform valid statistical comparisons. Our results indicate that the permuted design was able to capture more anterior hippocampal activation compared to the block design, which emphasized more posterior hippocampal involvement. These differences were further investigated and attributed to a combination of the polymodal stimuli we used and the experimental design. Activation patterns during encoding in both designs occurred along the entire longitudinal axis of the hippocampus, but with different centers of gravity. The maximal activated voxel in the block design was situated in the posterior half of the hippocampus while in the permuted design this was located in the anterior half. (orig.)

Hippocampal activation during face-name associative memory encoding: blocked versus permuted design

Energy Technology Data Exchange (ETDEWEB)

De Vogelaere, Frederick; Vingerhoets, Guy [Ghent University, Laboratory for Neuropsychology, Department of Neurology, Ghent (Belgium); Santens, Patrick; Boon, Paul [Ghent University Hospital, Department of Neurology, Ghent (Belgium); Achten, Erik [Ghent University Hospital, Department of Radiology, Ghent (Belgium)

2010-01-15

The contribution of the hippocampal subregions to episodic memory through the formation of new associations between previously unrelated items such as faces and names is established but remains under discussion. Block design studies in this area of research generally tend to show posterior hippocampal activation during encoding of novel associational material while event-related studies emphasize anterior hippocampal involvement. We used functional magnetic resonance imaging to assess the involvement of anterior and posterior hippocampus in the encoding of novel associational material compared to the viewing of previously seen associational material. We used two different experimental designs, a block design and a permuted block design, and applied it to the same associative memory task to perform valid statistical comparisons. Our results indicate that the permuted design was able to capture more anterior hippocampal activation compared to the block design, which emphasized more posterior hippocampal involvement. These differences were further investigated and attributed to a combination of the polymodal stimuli we used and the experimental design. Activation patterns during encoding in both designs occurred along the entire longitudinal axis of the hippocampus, but with different centers of gravity. The maximal activated voxel in the block design was situated in the posterior half of the hippocampus while in the permuted design this was located in the anterior half. (orig.)

[The hip joint in neuromuscular disorders].

Science.gov (United States)

Strobl, W M

2009-07-01

Physiologic motor and biomechanical parameters are prerequisites for normal hip development and hip function. Disorders of muscle activity and lack of weight bearing due to neuromuscular diseases may cause clinical symptoms such as an unstable hip or reduced range of motion. Disability and handicap because of pain, hip dislocation, osteoarthritis, gait disorders, or problems in seating and positioning are dependent on the severity of the disease, the time of occurrence, and the means of prevention and treatment. Preservation of pain-free and stable hip joints should be gained by balancing muscular forces and by preventing progressive dislocation. Most important is the exact indication of therapeutic options such as movement and standing therapy as well as drugs and surgery.

FUNCTIONS OF A NEUROMUSCULAR CENTRE

Directory of Open Access Journals (Sweden)

Janez Zidar

2004-12-01

Full Text Available Main functions of a neuromuscular (NM centre are making diagnosis, treatment and counselling. Some other functions, e. g. forming a register and epidemiological endeavours, could be added. All these activities are expected to be achieved by multidisciplinary approach with the idea that members use the same guidelines and share the same knowledge.NM diseases affect lower levels of the nervous system that is motor units (motor cells in the brainstem and spinal cord, nerve roots, cranial and peripheral nerves, neuromuscular junction, and muscles. There are many such diseases; a few are more common others are rare.Rational approach in making a diagnosis can be divided into several steps. The process begins with a person with clinical symptoms and signs which raise the suspicion of NM disease. The first step is the description of the predominant pattern of muscular wasting and weakness (e. g. limb-girdle, distal, ocular, facio-scapulo-humeral. Each of these syndromes require a differential diagnosis within the motor unit territory what is achieved by means of EMG and muscle biopsy. The latter is even more important to define the nature of the abnormality. Disease nature can also be determined biochemically and, as NM disorders are commonly genetically determined, at the molecular genetic level. Treatment modalities include drugs (causative and symptomatic and other measures such as promoting and maintaining good general health, preventing skeletal deformities, physiotherapy, orthoses, surgery, and prevention of respiratory and cardiac functions. Counselling is mainly by social workers that focus on the practical aspects of coping with illness and disability and by genetic counsellors who gave advise on family planning.

Neuromuscular paralysis by the basic phospholipase A2 subunit of crotoxin from Crotalus durissus terrificus snake venom needs its acid chaperone to concurrently inhibit acetylcholine release and produce muscle blockage.

Science.gov (United States)

Cavalcante, Walter L G; Noronha-Matos, José B; Timóteo, Maria A; Fontes, Marcos R M; Gallacci, Márcia; Correia-de-Sá, Paulo

2017-11-01

Crotoxin (CTX), a heterodimeric phospholipase A 2 (PLA 2 ) neurotoxin from Crotalus durissus terrificus snake venom, promotes irreversible blockade of neuromuscular transmission. Indirect electrophysiological evidence suggests that CTX exerts a primary inhibitory action on transmitter exocytosis, yet contribution of a postsynaptic action of the toxin resulting from nicotinic receptor desensitization cannot be excluded. Here, we examined the blocking effect of CTX on nerve-evoked transmitter release measured directly using radioisotope neurochemistry and video microscopy with the FM4-64 fluorescent dye. Experiments were conducted using mice phrenic-diaphragm preparations. Real-time fluorescence video microscopy and liquid scintillation spectrometry techniques were used to detect transmitter exocytosis and nerve-evoked [ 3 H]-acetylcholine ([ 3 H]ACh) release, respectively. Nerve-evoked myographic recordings were also carried out for comparison purposes. Both CTX (5μg/mL) and its basic PLA 2 subunit (CB, 20μg/mL) had biphasic effects on nerve-evoked transmitter exocytosis characterized by a transient initial facilitation followed by a sustained decay. CTX and CB reduced nerve-evoked [ 3 H]ACh release by 60% and 69%, respectively, but only the heterodimer, CTX, decreased the amplitude of nerve-evoked muscle twitches. Data show that CTX exerts a presynaptic inhibitory action on ACh release that is highly dependent on its intrinsic PLA 2 activity. Given the high safety margin of the neuromuscular transmission, one may argue that the presynaptic block caused by the toxin is not enough to produce muscle paralysis unless a concurrent postsynaptic inhibitory action is also exerted by the CTX heterodimer. Copyright © 2017. Published by Elsevier Inc.

Effects of neuromuscular training on the reaction time and electromechanical delay of the peroneus longus muscle.

Science.gov (United States)

Linford, Christena W; Hopkins, J Ty; Schulthies, Shane S; Freland, Brent; Draper, David O; Hunter, Iain

2006-03-01

To examine the influence of a 6-week neuromuscular training program on the electromechanical delay and reaction time of the peroneus longus muscle. A 2 x 2 pre-post factorial design. Human performance research center biomechanics laboratory. Thirty-six healthy, physically active, college-age subjects were recruited for this study and 26 completed it. There were 5 men and 8 women in the treatment group (mean age +/- standard deviation, 21.9+/-2.1 y; height, 173.7+/-11.1cm; weight, 67.4+/-17.8 kg) and 6 men and 7 women in the control group (age, 21.8+/-2.3 y; height, 173.7+/-11.9 cm; weight, 70.8+/-19.4 kg). Subjects were not currently experiencing any lower-extremity pathology and had no history of injuries requiring treatment to either lower extremity. Subjects in the treatment group completed a 6-week neuromuscular training program involving various therapeutic exercises. Subjects in the control group were asked to continue their normal physical activity during the 6-week period. The electromechanical delay of the peroneus longus was determined by the onset of force contribution after artificial activation, as measured by electromyographic and forceplate data. Reaction time was measured after a perturbation during walking. Data were analyzed using two 2 x 2 analyses of covariance (covariate pretest score). Group (treatment, control) and sex (male, female) were between-subject factors. Neuromuscular training caused a decrease in reaction time to perturbation during walking compared with controls (F=4.030, P=.029), while there was a trend toward an increase in electromechanical delay (F=4.227, P=.052). There was no significant difference between sexes or the interaction of sex and treatment in either reaction time or electromechanical delay. The 6-week training program significantly reduced reaction time of the peroneus longus muscle in healthy subjects. Neuromuscular training may have a beneficial effect on improving dynamic restraint during activity.

Vocational perspectives and neuromuscular disorders

NARCIS (Netherlands)

Andries, F.; Wevers, C. W.; Wintzen, A. R.; Busch, H. F.; Höweler, C. J.; de Jager, A. E.; Padberg, G. W.; de Visser, M.; Wokke, J. H.

1997-01-01

The present study analyses the actual occupational situation, vocational handicaps and past labour career of a group of about 1000 Dutch patients suffering from a neuromuscular disorder (NMD). On the basis of the likelihood of a substantial employment history and sufficient numbers of patients, four

Vocational perspectives and neuromuscular disorders

NARCIS (Netherlands)

Andries, F; Wevers, CWJ; Wintzen, AR; Busch, HFM; Howeler, CJ; deJager, AEJ; Padberg, GW; deVisser, M; Wokke, JHJ

The present study analyses the actual occupational situation, vocational handicaps and past labour career of a group of about 1000 Dutch patients suffering from a neuromuscular disorder (NMD). On the basis of the likelihood of a substantial employment history and sufficient numbers of patients, four

Neuromuscular training to enhance sensorimotor and functional deficits in subjects with chronic ankle instability: a systematic review and best evidence synthesis

LENUS (Irish Health Repository)

O'Driscoll, Jeremiah

2011-09-22

Abstract Objective To summarise the available evidence for the efficacy of neuromuscular training in enhancing sensorimotor and functional deficits in subjects with chronic ankle instability (CAI). Design Systematic review with best evidence synthesis. Data Sources An electronic search was conducted through December 2009, limited to studies published in the English language, using the Pubmed, CINAHL, Embase, and SPORTDiscus databases. Reference screening of all included articles was also undertaken. Methods Studies were selected if the design was a RCT, quasi RCT, or a CCT; the patients were adolescents or adults with confirmed CAI; and one of the treatment options consisted of a neuromuscular training programme. The primary investigator independently assessed the risk of study bias and extracted relevant data. Due to clinical heterogeneity, data was analysed using a best-evidence synthesis. Results Fourteen studies were included in the review. Meta-analysis with statistical pooling of data was not possible, as the studies were considered too heterogeneous. Instead a best evidence synthesis was undertaken. There is limited to moderate evidence to support improvements in dynamic postural stability, and patient perceived functional stability through neuromuscular training in subjects with CAI. There is limited evidence of effectiveness for neuromuscular training for improving static postural stability, active and passive joint position sense (JPS), isometric strength, muscle onset latencies, shank\\/rearfoot coupling, and a reduction in injury recurrence rates. There is limited evidence of no effectiveness for improvements in muscle fatigue following neuromuscular intervention. Conclusion There is limited to moderate evidence of effectiveness in favour of neuromuscular training for various measures of static and dynamic postural stability, active and passive JPS, isometric strength, muscle onset latencies, shank\\/rearfoot coupling and injury recurrence rates. Strong

Neuromuscular Effects of Rocuronium Bromide in Patients in Statin Therapy for at least Three Months.

Science.gov (United States)

Ren, Hongwei; Lv, Huangwei

2016-12-01

Statins cause skeletal muscle myopathy. However, the neuromuscular effects of non-depolarizing neuromuscular-blocking agent in patients in long-term statin therapy remain unclear. Hence, we investigated the neuromuscular effects of rocuronium and muscle injury in patients in long-term statin therapy. Eighteen statin users using statins for at least 3 months were included in the statin group and 18 non-statin users were included in the non-statin group. General anaesthesia was induced with intravenous midazolam, etomidate, sufentanil and rocuronium 0.9 mg/kg (3ED 95 ) for intubation. Anaesthesia was maintained with 1% propofol and remifentanil. The onset time and duration 10% T 1 and 25% T 1 of rocuronium were recorded. Blood samples were obtained before induction and 5 min., 1 hr, 2 hr, 4 hr, 12 hr and 24 hr after rocuronium administration to measure creatine kinase (CK), myoglobin and potassium. Myalgia was determined at 2 and 24 hr after surgery. There were no significant differences in the basic clinical characteristics between the two groups. The onset time of the statin group was significantly shorter than that of the non-statin group (p = 0.02), while the duration 10% T 1 and duration 25% T 1 of the statin group were significantly longer than those of the non-statin group (p = 0.006; p = 0.045). The myoglobin and CK concentrations increased after rocuronium administration as compared to baseline in both groups. CK concentration in the statin group was significantly higher than in the non-statin group just at 24 hr (p = 0.000003). However, myoglobin showed no significant difference between the two groups. The onset time of rocuronium decreases and its duration time increases in patients in long-term statin therapy. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Immediate effect of selective neuromuscular electrical stimulation on the electromyographic activity of the vastus medialis oblique muscle

Directory of Open Access Journals (Sweden)

Jamilson Simões Brasileiro

2008-04-01

Full Text Available The Patellofemoral pain syndrome (PFPS is described as an anterior or retropatellar knee pain in the absence of other associated diseases, and has often been associated with dysfunction of the vastus medialis oblique muscle (VMO. However, several studies have demonstrated the impossibility of selectively activating this muscle with exercises. The aim of the present study was to analyze the immediate effect of neuromuscular electrical stimulation of VMO muscle by means of monitoring the electromyographic activity of the vastus medialis oblique (VMO and vastus lateralis (VL muscles. Eighteen healthy women with a mean age of 23.2 years and mean BMI of 20 Kg/m2 were evaluated. The study protocol included electromyographic analysis of VMO and VL muscles, before and immediately after neuromuscular electrical stimulation of the VMO muscle. During the electromyographic analysis, the volunteers performed maximal voluntary isometric contraction in a 60° knee extension on an isokinetic dynamometer. “Russian current” apparatus was used for electrical stimulation. Results: The data analysis demonstrated a signifi cant increase in VMO activation intensity immediately after it had been electrically stimulated (p=0.0125, whereas VL activation intensity exhibited no signifi cant increase (p=0.924. Moreover, a significant increase in the VMO/VL ratio was also detected (p=0.048. In this study it was observed that electrical stimulation modifiedthe VMO/VL ratio, which suggests electrical stimulation has a benefi cial effect on VMO muscle strength. Resumo A Síndrome da dor patelofemoral (SDPF é descrita como dor anterior ou retro-patelar do joelho na ausência de outras patologias associadas, sendo freqüentemente associada à disfunção do Vasto Medial Oblíquo (VMO. Entretanto, diversos estudos têm demonstrado a impossibilidade de ativar seletivamente este músculo através de exercícios. O objetivo do presente estudo foi analisar o efeito imediato da

Neuromuscular Exercise Post Partial Medial Meniscectomy

DEFF Research Database (Denmark)

Hall, Michelle; Hinman, Rana S; Wrigley, Tim V

2015-01-01

PURPOSE: To evaluate the effects of a 12-week, home-based, physiotherapist-guided neuromuscular exercise program on the knee adduction moment (an indicator of mediolateral knee load distribution) in people with a medial arthroscopic partial meniscectomy within the past 3-12 months. METHODS......: An assessor-blinded, randomised controlled trial including people aged 30-50 years with no to mild pain following medial arthroscopic partial meniscectomy was conducted. Participants were randomly allocated to either a 12-week neuromuscular exercise program that targeted neutral lower limb alignment...... or a control group with no exercise. The exercise program included eight individual sessions with one of seven physiotherapists in private clinics, together with home exercises. Primary outcomes were the peak external knee adduction moment during normal pace walking and during a one-leg sit-to-stand. Secondary...

Effects of sugammadex on incidence of postoperative residual neuromuscular blockade

DEFF Research Database (Denmark)

Brueckmann, B; Sasaki, N; Grobara, P

2015-01-01

BACKGROUND: This study aimed to investigate whether reversal of rocuronium-induced neuromuscular blockade with sugammadex reduced the incidence of residual blockade and facilitated operating room discharge readiness. METHODS: Adult patients undergoing abdominal surgery received rocuronium, followed...... by randomized allocation to sugammadex (2 or 4 mg kg(-1)) or usual care (neostigmine/glycopyrrolate, dosing per usual care practice) for reversal of neuromuscular blockade. Timing of reversal agent administration was based on the providers' clinical judgement. Primary endpoint was the presence of residual...... measured at PACU entry. Zero out of 74 sugammadex patients and 33 out of 76 (43.4%) usual care patients had TOF-Watch® SX-assessed residual neuromuscular blockade at PACU admission (odds ratio 0.0, 95% CI [0-0.06], P

Distinct neural and neuromuscular strategies underlie independent evolution of simplified advertisement calls.

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Leininger, Elizabeth C; Kelley, Darcy B

2013-04-07

Independent or convergent evolution can underlie phenotypic similarity of derived behavioural characters. Determining the underlying neural and neuromuscular mechanisms sheds light on how these characters arose. One example of evolutionarily derived characters is a temporally simple advertisement call of male African clawed frogs (Xenopus) that arose at least twice independently from a more complex ancestral pattern. How did simplification occur in the vocal circuit? To distinguish shared from divergent mechanisms, we examined activity from the calling brain and vocal organ (larynx) in two species that independently evolved simplified calls. We find that each species uses distinct neural and neuromuscular strategies to produce the simplified calls. Isolated Xenopus borealis brains produce fictive vocal patterns that match temporal patterns of actual male calls; the larynx converts nerve activity faithfully into muscle contractions and single clicks. In contrast, fictive patterns from isolated Xenopus boumbaensis brains are short bursts of nerve activity; the isolated larynx requires stimulus bursts to produce a single click of sound. Thus, unlike X. borealis, the output of the X. boumbaensis hindbrain vocal pattern generator is an ancestral burst-type pattern, transformed by the larynx into single clicks. Temporally simple advertisement calls in genetically distant species of Xenopus have thus arisen independently via reconfigurations of central and peripheral vocal neuroeffectors.

The relationship between rate of administration of an intubating dose of rocuronium and time to 50% and 90% block at the adductor pollicis muscle

NARCIS (Netherlands)

De Haes, A; Eleveld, DJ; Wierda, JMKH

2000-01-01

Objective. To determine the relationship between the rate of rocuronium injection and the onset time of neuromuscular block. Methods.After intravenous induction, 60 female patients (ASA I-II) were assigned randomly into 3 groups for rocuronium administration within 1-15, 15-30 or 30-60 seconds.

Reversal of profound rocuronium neuromuscular blockade by sugammadex in anesthetized rhesus monkeys.

NARCIS (Netherlands)

Boer, H.D. de; Egmond, J. van; Pol, F. van de; Bom, A.; Booij, L.H.D.J.

2006-01-01

BACKGROUND: Reversal of neuromuscular blockade can be accomplished by chemical encapsulation of rocuronium by sugammadex, a synthetic gamma-cyclodextrin derivative. The current study determined the feasibility of reversal of rocuronium-induced profound neuromuscular blockade with sugammadex in the

[Impact of sugammadex on neuromuscular blocking agents use: a multicentric, pharmaco-epidemiologic study in French university hospitals and military hospitals].

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Beny, K; Piriou, V; Dussart, C; Hénaine, R; Aulagner, G; Armoiry, X

2013-12-01

Seven Neuromuscular Blocking Agents (NMBA) are commercialized in France. Four of them have an intermediate duration of action. Sugammadex required the use of NMBA slightly employed in clinical practice in France. Its introduction in routine practice could have an impact on NMBA use in clinical practice. This study was then conducted to assess and compare NMBA use before and after the commercialization of sugammadex. A longitudinal, retrospective, observational study was conducted between 2008 and 2011 in French university hospitals and military hospitals. The consumption data for sugammadex and NMBA were collected using a collection grid which was filled by pharmacists or anesthesiologists. Drug use was measured by the number of vials used divided by the annual number of hospitalizations in surgery and obstetrics (HSO). An overall analysis of the annual frequency of NMBA use was firstly performed, then individual data of each hospital were analyzed. Descriptive statistical analysis including mean, standard deviation, median, minimum and maximum was achieved. Thirty-four out of 39 hospitals participated in the study (87%) and analysis was performed on 26 of them (7%). The data of eight institutions were excluded due to missing values or because of the non-admission of sugammadex in their formulary. The NMBA mostly used were non-steroidal NMBA (75% of market share) with an increased use between 2008 and 2011 concerning atracurium (from 41 to 51 vials of 50mg atracurium used per 100 HSO). The overall analysis revealed an increase of the occurrence of rocuronium (between 2008 and 2011: from 1 to 4.8 vials of 50mg rocuronium used per 100 HSO). Individual analyses on each hospital showed a possible effect of sugammadex introduction on NMBA use in nine hospitals. The commercialization of sugammadex seems to have induced a discrete increase of steroidal NMBA but non-steroidal NMBA remain the leading agent in France. A long-term follow-up is deserved. Copyright © 2013 Soci

Dengue-associated neuromuscular complications

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Ravindra Kumar Garg; Hardeep Singh Malhotra; Amita Jain; Kiran Preet Malhotra

2015-01-01

Dengue is associated with many neurological dysfunctions. Up to 4% of dengue patients may develop neuromuscular complications. Muscle involvement can manifest with myalgias, myositis, rhabdomyolysis and hypokalemic paralysis. Diffuse myalgia is the most characteristic neurological symptom of dengue fever. Dengue-associated myositis can be of varying severity ranging from self-limiting muscle involvement to severe dengue myositis. Dengue-associated hypokalemic paralysis often has a rapidly evo...

Effects of six weeks of resistance exercise with reciprocal contractions on knee extensors neuromuscular performance : Randomized controlled trial

NARCIS (Netherlands)

Cardoso, Euler; Bottaro, Martim; Rodrigues, Pâmella; Souza, Igor Eduardo; Durigan, João; Lima, Ricardo Moreno; Júnior, Silvio Assis Oliveira; Carregaro, Rodrigo Luiz

2015-01-01

BACKGROUND: Studies have shown that reciprocal exercise using a pre-Activation of antagonist muscles may increase the agonist neuromuscular performance. OBJECTIVE: To compare the efficiency of two modalities of resistance training (with and without antagonist muscle pre-Activation) during a six week

Silent synapses in neuromuscular junction development.

Science.gov (United States)

Tomàs, Josep; Santafé, Manel M; Lanuza, Maria A; García, Neus; Besalduch, Nuria; Tomàs, Marta

2011-01-01

In the last few years, evidence has been found to suggest that some synaptic contacts become silent but can be functionally recruited before they completely retract during postnatal synapse elimination in muscle. The physiological mechanism of developmental synapse elimination may be better understood by studying this synapse recruitment. This Mini-Review collects previously published data and new results to propose a molecular mechanism for axonal disconnection. The mechanism is based on protein kinase C (PKC)-dependent inhibition of acetylcholine (ACh) release. PKC activity may be stimulated by a methoctramine-sensitive M2-type muscarinic receptor and by calcium inflow though P/Q- and L-type voltage-dependent calcium channels. In addition, tropomyosin-related tyrosine kinase B (trkB) receptor-mediated brain-derived neurotrophic factor (BDNF) activity may oppose the PKC-mediated ACh release depression. Thus, a balance between trkB and muscarinic pathways may contribute to the final functional suppression of some neuromuscular synapses during development. © 2010 Wiley-Liss, Inc.

Ação neuro-muscular do veneno crotálico: dados preliminares Neuromuscular action of crotalid venom: preliminar data

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Maria Dorvalina Silva

1996-03-01

Full Text Available Estudamos 6 pacientes, 2 cães e um coelho com intoxicação crotálica. Avaliamos a condução nervosa periférica sensitiva e motora, a transmissão neuromuscular e eletromiografias. As biópsias de músculo foram processadas por histoquímica. Os 6 pacientes apresentaram mononeuropatia sensitiva no nervo periférico adjacente ao local da inoculação do veneno e encontramos evidências histoquímicas de miopatia mitocondrial. Os defeitos da transmissão neuromuscular foram mínimos. A maioria dos autores admite que veneno crotálico determina síndrome miastênica. Nossos achados indicam que ptose palpebral, facies miastênico e fraqueza muscular observados após acidente crotálico, correspondem provavelmente a miopatia mitocondrial, muitas vezes transitória e reversível.We studied 6 patients and 2 dogs that have been bitten by South American rattlesnake Crotalus durissus terrificus and one rabbit inoculated with crotalid venom. We analized sensory and motor peripheral nerve conduction, repetitive stimulation for studying neuromuscular transmission and electromyographies. Muscle biopsies were processed by histochemistry. All patients had peripheral mononeuropathy of the closest sensitive nerve to the area of snakebite. The neuromuscular transmission alterations were minimal. Muscle histochemistry of 4 patients, 2 dogs and 1 rabbit showed findings of mitochondrial myopathy. The majority of authors admit that crotalid venom causes myastenic syndrome. Our findings suggest that palpebral ptosis, myastenic facies and muscular weakness observed after crotalid poisoning are, probably, due to transient and reversible mitochondrial myopathy. As far as we know, this is the first report on the ability of the venom of this rattlesnake to cause local sensitive mononeuropathy and the first muscle histochemistry showing mitochondrial myopathy in humans poisoned by crotalid venom.

A Dutch guideline for the treatment of scoliosis in neuromuscular disorders

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Titarsolej PJ

2008-09-01

Full Text Available Abstract Background Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care. Methods The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence. Results For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands. Conclusion In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.

Biomechanical and neuromuscular characteristics of male athletes: implications for the development of anterior cruciate ligament injury prevention programs.

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Sugimoto, Dai; Alentorn-Geli, Eduard; Mendiguchía, Jurdan; Samuelsson, Kristian; Karlsson, Jon; Myer, Gregory D

2015-06-01

Prevention of anterior cruciate ligament (ACL) injury is likely the most effective strategy to reduce undesired health consequences including reconstruction surgery, long-term rehabilitation, and pre-mature osteoarthritis occurrence. A thorough understanding of mechanisms and risk factors of ACL injury is crucial to develop effective prevention programs, especially for biomechanical and neuromuscular modifiable risk factors. Historically, the available evidence regarding ACL risk factors has mainly involved female athletes or has compared male and female athletes without an intra-group comparison for male athletes. Therefore, the principal purpose of this article was to review existing evidence regarding the investigation of biomechanical and neuromuscular characteristics that may imply aberrant knee kinematics and kinetics that would place the male athlete at risk of ACL injury. Biomechanical evidence related to knee kinematics and kinetics was reviewed by different planes (sagittal and frontal/coronal), tasks (single-leg landing and cutting), situation (anticipated and unanticipated), foot positioning, playing surface, and fatigued status. Neuromuscular evidence potentially related to ACL injury was reviewed. Recommendations for prevention programs for ACL injuries in male athletes were developed based on the synthesis of the biomechanical and neuromuscular characteristics. The recommendations suggest performing exercises with multi-plane biomechanical components including single-leg maneuvers in dynamic movements, reaction to and decision making in unexpected situations, appropriate foot positioning, and consideration of playing surface condition, as well as enhancing neuromuscular aspects such as fatigue, proprioception, muscle activation, and inter-joint coordination.

[CLINICAL STUDIES ON EFFECT OF ARTHROSCOPIC INTERCONDYLAR FOSSA ANGIOPLASTY ON ABILITY OF NEUROMUSCULAR CONTROL IN ELDERLY PATIENTS WITH KNEE OSTEOARTHRITIS].

Science.gov (United States)

Huang, Jingmin; Wang, Haijiao; Wu, Jiang; Li, Dongchao; Li, Yuhong

2015-08-01

To study the effect of arthroscopic intercondylar fossa angioplasty on the ability of neuromuscular control of the knee joint in elderly patients with knee osteoarthritis (KOA). Between June 2012 and March 2013, 20 elderly patients with KOA and in accordance with inclusion and exclusion criteria underwent arthroscopic intercondylar fossa angioplasty (operation group), and 20 healthy elderly people served as control group. There was no significant difference in age, height, weight, and body mass index between 2 groups (P > 0.05). The proprioception capability (using passive regeneration test at measurement angles of 15, 30, and 60°) and quadriceps mobilization [including maximum voluntary contraction (MVC), central activation ratio (CAR), and activation deficit (AD)] were measured to avaluate the neuromuscular control of the knee; the Lysholm score was used to evaluate knee function. The above indexes were measured to assess the knee neuromuscular control and recovery of joint function in patients of operation group at 3, 6, and 9 months after operation. Compared with the control group, MVC, CAR, and Lysholm scores were significantly decreased, and the AD and passive knee angle difference were significantly increased in operation group (P 0.05). Arthroscopic intercondylar fossa angioplasty can relieve ACL pressure, abrasion, and impact, which will recover the ability of neuromuscular control, increase proprioception and quadriceps mobilization capacity, and improve the joint function.

Kinesiotaping enhances the rate of force development but not the neuromuscular efficiency of physically active young men

NARCIS (Netherlands)

Magalhães, Igor; Bottaro, Martim; Mezzarane, Rinaldo André; Neto, Frederico Ribeiro; Rodrigues, Bruno A.; Ferreira-Júnior, João B.; Carregaro, Rodrigo Luiz

2016-01-01

Introduction: Investigations on the effects of KT on human performance have been increasing in the last few years. However, there is a paucity of studies investigating its effects on neuromuscular efficiency (NME) and rate of force development (RFD). Objective: To evaluate the NME and RFD of the

Effects of regular Tai Chi practice and jogging on neuromuscular reaction during lateral postural control in older people.

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Wang, Shao-Jun; Xu, Dong-Qing; Li, Jing-Xian

2017-01-01

This study examined the effects of regular Tai Chi practice and jogging on the neuromuscular activity of the trunk, hip, and ankle joint muscles of older people during lateral postural perturbation. A total of 42 older people participated in the study and formed the Tai Chi, jogging, and sedentary control groups. Electromyography signals were collected from the peroneus longus, anterior tibialis, gluteus medius, and erector spinae during unpredictable mediolateral perturbation. The Tai Chi group exhibited significantly faster latencies of the tibialis anterior and erector spinae than the control group. The jogging group showed a significantly shorter neuromuscular reaction time of the erector spinae than the control group. No significant difference was observed between the Tai Chi and jogging groups. Long-term regular Tai Chi practice enhanced the neuromuscular reaction of the erector spinae and tibialis anterior to lateral perturbation and will help timely posture correction when lateral postural distributions occur.

The relative frequency of common neuromuscular diagnoses in a reference center.

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Cotta, Ana; Paim, Júlia Filardi; Carvalho, Elmano; da-Cunha-Júnior, Antonio Lopes; Navarro, Monica M; Valicek, Jaquelin; Menezes, Miriam Melo; Nunes, Simone Vilela; Xavier-Neto, Rafael; Baptista, Sidney; Lima, Luciano Romero; Takata, Reinaldo Issao; Vargas, Antonio Pedro

2017-11-01

The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. To report the relative frequency of common neuromuscular diagnoses in a reference center. A 17-year chart review of patients with suspicion of myopathy. Among 3,412 examinations, 1,603 (46.98%) yielded confirmatory results: 782 (48.78%) underwent molecular studies, and 821 (51.21%) had muscle biopsies. The most frequent diagnoses were: dystrophinopathy 460 (28.70%), mitochondriopathy 330 (20.59%), spinal muscular atrophy 158 (9.86%), limb girdle muscular dystrophy 157 (9.79%), Steinert myotonic dystrophy 138 (8.61%), facioscapulohumeral muscular dystrophy 99 (6.17%), and other diagnoses 261 (16.28%). Using the presently-available diagnostic techniques in this service, a specific limb girdle muscular dystrophy subtype diagnosis was reached in 61% of the patients. A neuromuscular-appropriate diagnosis is important for genetic counseling, rehabilitation orientation, and early treatment of respiratory and cardiac complications.

The relative frequency of common neuromuscular diagnoses in a reference center

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Ana Cotta

Full Text Available ABSTRACT The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. Objective: To report the relative frequency of common neuromuscular diagnoses in a reference center. Methods: A 17-year chart review of patients with suspicion of myopathy. Results: Among 3,412 examinations, 1,603 (46.98% yielded confirmatory results: 782 (48.78% underwent molecular studies, and 821 (51.21% had muscle biopsies. The most frequent diagnoses were: dystrophinopathy 460 (28.70%, mitochondriopathy 330 (20.59%, spinal muscular atrophy 158 (9.86%, limb girdle muscular dystrophy 157 (9.79%, Steinert myotonic dystrophy 138 (8.61%, facioscapulohumeral muscular dystrophy 99 (6.17%, and other diagnoses 261 (16.28%. Conclusion: Using the presently-available diagnostic techniques in this service, a specific limb girdle muscular dystrophy subtype diagnosis was reached in 61% of the patients. A neuromuscular-appropriate diagnosis is important for genetic counseling, rehabilitation orientation, and early treatment of respiratory and cardiac complications.

Neuromuscular fatigue and recovery profiles in individuals with intellectual disability

OpenAIRE

Borji , Rihab; Zghal , Firas; Zarrouk , Nidhal; Martin , Vincent; Sahli , Sonia; Rebai , Haithem

2017-01-01

International audience; Purpose: This study aimed to explore neuromuscular fatigue and recovery profiles in individuals with intellectual disability (ID) after exhausting submaximal contraction.Methods: Ten men with ID were compared to 10 men without ID. The evaluation of neuromuscular function consisted in brief (3 s) isometric maximal voluntary contraction (IMVC) of the knee extension superimposed with electrical nerve stimulation before, immediately after, and during 33 min after an exhaus...

Neuromuscular training to enhance sensorimotor and functional deficits in subjects with chronic ankle instability: A systematic review and best evidence synthesis

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O'Driscoll Jeremiah

2011-09-01

Full Text Available Abstract Objective To summarise the available evidence for the efficacy of neuromuscular training in enhancing sensorimotor and functional deficits in subjects with chronic ankle instability (CAI. Design Systematic review with best evidence synthesis. Data Sources An electronic search was conducted through December 2009, limited to studies published in the English language, using the Pubmed, CINAHL, Embase, and SPORTDiscus databases. Reference screening of all included articles was also undertaken. Methods Studies were selected if the design was a RCT, quasi RCT, or a CCT; the patients were adolescents or adults with confirmed CAI; and one of the treatment options consisted of a neuromuscular training programme. The primary investigator independently assessed the risk of study bias and extracted relevant data. Due to clinical heterogeneity, data was analysed using a best-evidence synthesis. Results Fourteen studies were included in the review. Meta-analysis with statistical pooling of data was not possible, as the studies were considered too heterogeneous. Instead a best evidence synthesis was undertaken. There is limited to moderate evidence to support improvements in dynamic postural stability, and patient perceived functional stability through neuromuscular training in subjects with CAI. There is limited evidence of effectiveness for neuromuscular training for improving static postural stability, active and passive joint position sense (JPS, isometric strength, muscle onset latencies, shank/rearfoot coupling, and a reduction in injury recurrence rates. There is limited evidence of no effectiveness for improvements in muscle fatigue following neuromuscular intervention. Conclusion There is limited to moderate evidence of effectiveness in favour of neuromuscular training for various measures of static and dynamic postural stability, active and passive JPS, isometric strength, muscle onset latencies, shank/rearfoot coupling and injury recurrence

Neuromechanical evidence of improved neuromuscular control around knee joint in volleyball players.

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Masci, Ilaria; Vannozzi, Giuseppe; Gizzi, Leonardo; Bellotti, Pasquale; Felici, Francesco

2010-02-01

The aim of the present work was to verify that skilled volleyball players present specific adaptations in both neuromuscular control and movement biomechanics, showing an improved neuromuscular control around the knee joint than in non-jumper athletes. Seven male volleyball players and seven male non-jumper athletes were recruited for this study. The following tests were performed in a random order: single countermovement jump (CMJ), single squat jump. At the end of the series, subjects performed a repetitive CMJ test. Electromyographic signals were recorded from vastus lateralis and biceps femoris muscles on both sides. Ground reaction forces and moments were measured with a force plate. Volleyball athletes performed better in all tests and were more resistant to fatigue than non-jumper athletes. Furthermore, volleyball athletes showed a reduced co-activation of knee flexor/extensor muscles. The present results seem to stand for a neural adaptation of the motor control scheme to training.

Joint angle affects volitional and magnetically-evoked neuromuscular performance differentially.

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Minshull, C; Rees, D; Gleeson, N P

2011-08-01

This study examined the volitional and magnetically-evoked neuromuscular performance of the quadriceps femoris at functional knee joint angles adjacent to full extension. Indices of volitional and magnetically-evoked neuromuscular performance (N=15 healthy males, 23.5 ± 2.9 years, 71.5 ± 5.4 kg, 176.5 ± 5.5 cm) were obtained at 25°, 35° and 45° of knee flexion. Results showed that volitional and magnetically-evoked peak force (PF(V) and P(T)F(E), respectively) and electromechanical delay (EMD(V) and EMD(E), respectively) were enhanced by increased knee flexion. However, greater relative improvements in volitional compared to evoked indices of neuromuscular performance were observed with increasing flexion from 25° to 45° (e.g. EMD(V), EMD(E): 36% vs. 11% improvement, respectively; F([2,14])=6.8, pjoint positions. These findings suggest that the extent of the relative differential between volitional and evoked neuromuscular performance capabilities is joint angle-specific and not correlated with performance capabilities at adjacent angles, but tends to be smaller with increased flexion. As such, effective prediction of volitional from evoked performance capabilities at both analogous and adjacent knee joint positions would lack robustness. Copyright © 2011 Elsevier Ltd. All rights reserved.

The effect of additional joint mobilization on neuromuscular performance in individuals with functional ankle instability.

Science.gov (United States)

Shih, Yi-Fen; Yu, Hsiang-Ting; Chen, Wen-Yin; Liao, Kwong-Kum; Lin, Hsiu-Chen; Yang, Yea-Ru

2018-03-01

To examine the effects of joint mobilization and exercise training on neuromuscular performance in individuals with functional ankle instability (FAI). A cross-sectional study. Forty five subjects with FAI were randomized into three groups: control (CG, n = 15, 27.9 ± 6.6yr), training (TG, n = 15, 26.9 ± 5.8yr) and mobilization with training group (MTG, n = 15, 26.5 ± 4.8yr). Four weeks of neuromuscular training for TG; neuromuscular training and joint mobilization for MTG. Electromyography of the peroneus longus (PL), tibialis anterior (TA), and soleus (SOL) and the reaching distance of the Y balance test (YBT), dorsiflexion range of motion (DFROM), Cumberland ankle instability tool (CAIT), and global rating scale (GRS). Two-way repeated measures MANOVA were used with the significance level p Joint mobilization resulted in additional benefits on self-reported ankle instability severity, dorsiflexion mobility, and posterolateral balance performance in individuals with FAI, but its effects on general improvement, muscle activation, and other balance tasks remained uncertain. Copyright © 2017 Elsevier Ltd. All rights reserved.

The pharmacological effect of Bothrops neuwiedii pauloensis (jararaca-pintada snake venom on avian neuromuscular transmission

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C.R. Borja-Oliveira

2003-05-01

Full Text Available The neuromuscular effects of Bothrops neuwiedii pauloensis (jararaca-pintada venom were studied on isolated chick biventer cervicis nerve-muscle preparations. Venom concentrations of 5-50 µg/ml produced an initial inhibition and a secondary increase of indirectly evoked twitches followed by a progressive concentration-dependent and irreversible neuromuscular blockade. At venom concentrations of 1-20 µg/ml, the responses to 13.4 mM KCl were inhibited whereas those to 110 µM acetylcholine alone and cumulative concentrations of 1 µM to 10 mM were unaffected. At venom concentrations higher than 50 µg/ml, there was pronounced muscle contracture with inhibition of the responses to acetylcholine, KCl and direct stimulation. At 20-24ºC, the venom (50 µg/ml produced only partial neuromuscular blockade (30.7 ± 8.0%, N = 3 after 120 min and the initial inhibition and the secondary increase of the twitch responses caused by the venom were prolonged and pronounced and the response to KCl was unchanged. These results indicate that B.n. pauloensis venom is neurotoxic, acting primarily at presynaptic sites, and that enzyme activity may be involved in this pharmacological action.

Report on Adaptive Force, a specific neuromuscular function

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Marko Hoff

2015-08-01

Full Text Available In real life motions, as well as in sports, the adaptation of the neuromuscular systems to externally applied forces plays an important role. The term Adaptive Force (AF shall characterize the ability of the nerve-muscle-system to adapt to impacting external forces during isometric and eccentric muscle action. The focus in this paper is on the concept of this neuromuscular action, which is not yet described in this way. A measuring system was constructed and evaluated for this specific neuromuscular function, but only the main information of the evaluation of the measuring system and the preliminary reference values are mentioned here, while an article with detailed description will be published separately. This paper concentrates on the three following points: 1 What is the peculiarity of this neuromuscular function, introduced as AF? 2 Is the measuring system able to capture its specific characteristics and which phases of measurement occur? 3 It seems reasonable to discuss if AF can be distinguished and classified among the known force concepts. The article describes the measuring system and how it is able to capture special features of real life motions like submaximal intensities and the subjects’ option to react adequately on external varying forces. Furthermore, within one measurement the system records three different force qualities: the isometric submaximal Adaptive Force (AFiso, the maximal isometric Adaptive Force (AFisomax and the maximal eccentric Adaptive Force (AFeccmax. Each of these phases provide different and unique information on the nerve-muscle-system that are discussed in detail. Important, in terms of the Adaptive Force, seems to be the combination of conditional and coordinative abilities.

Neuromuscular partitioning in the extensor carpi radialis longus and brevis based on intramuscular nerve distribution patterns: A three-dimensional modeling study.

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Ravichandiran, Mayoorendra; Ravichandiran, Nisanthini; Ravichandiran, Kajeandra; McKee, Nancy H; Richardson, Denyse; Oliver, Michele; Agur, Anne M

2012-04-01

Differential activation of specific regions within a skeletal muscle has been linked to the presence of neuromuscular compartments. However, few studies have investigated the extra- or intramuscular innervation throughout the muscle volume of extensor carpi radialis longus (ECRL) and brevis (ECRB). The aim of this study was to determine the presence of neuromuscular partitions in ECRL and ECRB based on the extra- and intramuscular innervation using three-dimensional modeling. The extra- and intramuscular nerve distribution was digitized and reconstructed in 3D in all the muscle volumes using Autodesk Maya in seven formalin embalmed cadaveric specimens (mean age, 75.7 ± 15.2 years). The intramuscular nerve distribution was modeled in all the muscle volumes. ECRL was found to have two neuromuscular compartments, superficial and deep. One branch from the radial nerve proper was found to innervate ECRL. This branch was divided into anterior and posterior branches to the superficial and deep compartments, respectively. Five innervation patterns were identified in ECRB with partitioning of the muscle belly into two, three, or four compartments, in a proximal to distal direction depending on the number of nerve branches entering the muscle belly. The ECRL and ECRB both demonstrated neuromuscular compartmentalization based on intramuscular innervation. According to the partitioning hypothesis, a muscle may be differentially activated depending on the required function of the muscle, thus allowing multifunctional muscles to contribute to a variety of movements. Therefore, the increased number of neuromuscular partitions in ECRB when compared with ECRL could be due to the need for more differential recruitment in the ECRB depending on force requirements. Copyright © 2011 Wiley Periodicals, Inc.

Anthropogenic Changes in Mid-latitude Storm and Blocking Activities from Observations and Climate Models

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Li, D.

2017-12-01

Fingerprints of anthropogenic climate change can be most readily detected in the high latitudes of Northern Hemisphere, where temperature has been rising faster than the rest of the globe and sea ice cover has shrunk dramatically over recent decades. Reducing the meridional temperature gradient, this amplified warming over the high latitudes influences weather in the middle latitudes by modulating the jet stream, storms, and atmospheric blocking activities. Whether observational records have revealed significant changes in mid-latitude storms and blocking activities, however, has remained a subject of much debate. Buried deep in strong year-to-year variations, the long-term dynamic responses of the atmosphere are more difficult to identify, compared with its thermodynamic responses. Variabilities of decadal and longer timescales further obscure any trends diagnosed from satellite observations, which are often shorter than 40 years. Here, new metrics reflecting storm and blocking activities are developed using surface air temperature and pressure records, and their variations and long-term trends are examined. This approach gives an inkling of the changes in storm and blocking activities since the Industrial Revolution in regions with abundant long-term observational records, e.g. Europe and North America. The relationship between Atlantic Multi-decadal Oscillation and variations in storm and blocking activities across the Atlantic is also scrutinized. The connection between observed centennial trends and anthropogenic forcings is investigated using a hierarchy of numerical tools, from highly idealized to fully coupled atmosphere-ocean models. Pre-industrial control simulations and a set of large ensemble simulations forced by increased CO2 are analyzed to evaluate the range of natural variabilities, which paves the way to singling out significant anthropogenic changes from observational records, as well as predicting future changes in mid-latitude storm and

Postoperative effects of neuromuscular exercise prior to hip or knee arthroplasty

DEFF Research Database (Denmark)

Villadsen, Allan; Overgaard, Søren; Holsgaard-Larsen, Anders

2014-01-01

neuromuscular exercise prior to total joint arthroplasty (TJA) of the hip or knee did not confer additional benefits 3 months postoperatively compared with TJA alone. However, the intervention group experienced a statistically significant short-term benefit in ADL and pain, suggesting an earlier onset......OBJECTIVE: To investigate the postoperative efficacy of a supervised programme of neuromuscular exercise prior to hip or knee arthroplasty. METHODS: In this assessor-blinded randomised controlled trial, we included 165 patients scheduled for hip or knee arthroplasty due to severe osteoarthritis (OA......). An 8-week preoperative neuromuscular supervised exercise programme was delivered twice a week for 1 h as adjunct treatment to the standard arthroplasty procedure and compared with the standard arthroplasty procedure alone. The primary outcome was self-reported physical function measured...

Protein kinase C involvement in the acetylcholine release reduction induced by amyloid-beta(25-35) aggregates on neuromuscular synapses.

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Tomàs, Marta; Garcia, Neus; Santafé, Manuel M; Lanuza, Maria; Tomàs, Josep

2009-01-01

Using intracellular recording of the diaphragm muscle of adult rats, we have investigated the short-term functional effects of amyloid-beta (Abeta(25-35) peptide aggregates on the modulation of acetylcholine (ACh) release and the involvement of protein kinase C (PKC). The non-aggregated form of this peptide does not change the evoked and spontaneous transmitter release parameters on the neuromuscular synapse. However, the aggregated form of Abeta(25-35) acutely interferes with evoked quantal ACh release (approximately 40% reduction) when synaptic activity in the ex vivo neuromuscular preparation is maintained by low frequency (1 Hz) electrical stimulation. This effect is partially dependent on the activity of PKC that may have a permissive action. The end result of Abeta(25-35) is in opposition to the PKC-dependent maintenance effect on ACh release manifested in active synapses.

Utilization of ACL Injury Biomechanical and Neuromuscular Risk Profile Analysis to Determine the Effectiveness of Neuromuscular Training.

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Hewett, Timothy E; Ford, Kevin R; Xu, Yingying Y; Khoury, Jane; Myer, Gregory D

2016-12-01

The widespread use of anterior cruciate ligament (ACL) injury prevention interventions has not been effective in reducing the injury incidence among female athletes who participate in high-risk sports. The purpose of this study was to determine if biomechanical and neuromuscular factors that contribute to the knee abduction moment (KAM), a predictor of future ACL injuries, could be used to characterize athletes by a distinct factor. Specifically, we hypothesized that a priori selected biomechanical and neuromuscular factors would characterize participants into distinct at-risk profiles. Controlled laboratory study. A total of 624 female athletes who participated in jumping, cutting, and pivoting sports underwent testing before their competitive season. During testing, athletes performed drop-jump tasks from which biomechanical measures were captured. Using data from these tasks, latent profile analysis (LPA) was conducted to identify distinct profiles based on preintervention biomechanical and neuromuscular measures. As a validation, we examined whether the profile membership was a significant predictor of the KAM. LPA using 6 preintervention biomechanical measures selected a priori resulted in 3 distinct profiles, including a low (profile 1), moderate (profile 2), and high (profile 3) risk for ACL injuries. Athletes with profiles 2 and 3 had a significantly higher KAM compared with those with profile 1 (P risk profiles. Three distinct risk groups were identified based on differences in the peak KAM. These findings demonstrate the existence of discernable groups of athletes that may benefit from injury prevention interventions. ClinicalTrials.gov NCT identifier: NCT01034527. © 2016 The Author(s).

Conservative management of neuromuscular scoliosis: personal experience and review of literature.

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Kotwicki, Tomasz; Jozwiak, Marek

2008-01-01

The principles of conservative management of neuromuscular scoliosis in childhood and adolescence are presented. Analysis of personal experience and literature review. The topic is discussed separately for patients with flaccid or spastic paresis. These demonstrate that conservative management might be proposed for patients with neuromuscular scoliosis in many clinical situations. In spastic disorders, it maintains the symmetry around the hip joints. Bracing is technically difficult and often is not tolerated well by cerebral palsy children. In patients with flaccid paresis, the fitting and the use of brace is easier than in spastic patients. The flexibility of the spinal curvature is more important. Functional benefits of conservative management of neuromuscular scoliosis comprise stable sitting, easier use of upper limbs, discharge of the abdomen from the collapsing trunk, increased diaphragm excursion, and, not always, prevention of curve progression. Specific natural history and multiple medical problems associated with the disease make the treatment of children with neuromuscular scoliosis an extremely complex issue, best addressed when a team approach is applied. Continuously improving techniques of conservative management, comprising bracing and physiotherapy, together with correctly timed surgery incorporated in the process of rehabilitation, provide the optimal care for patients.

VARIATIONS IN NEUROMUSCULAR ACTIVITY OF THIGH MUSCLES DURING WHOLE-BODY VIBRATION IN CONSIDERATION OF DIFFERENT BIOMECHANICAL VARIABLES

Directory of Open Access Journals (Sweden)

Dennis Perchthaler

2013-09-01

Full Text Available The intention of this study was to systematically analyze the impact of biomechanical variables in terms of different vibration frequencies, amplitudes and knee angles on quadriceps femoris and hamstring activity during exposure to whole-body vibration (WBV. 51 healthy men and women (age 55 ± 8 years voluntary participated in the study and were randomly allocated to five different vibration-frequency groups. Each subject performed 9 static squat positions (3 amplitudes x 3 knee angles on a side alternating vibration platform. Surface electromyography (EMG was used to record the neuromuscular activity of the quadriceps femoris and hamstring muscles. Maximal voluntary contractions (MVCs were performed prior to the measurements to normalize the EMG signals. A three-way mixed ANOVA was performed to analyze the different effects of the biomechanical variables on muscle activity. Depending on the biomechanical variables, EMG muscle activity ranged between 18.2 and 74.1 % MVC in the quadriceps femoris and between 5.2 and 27. 3 % MVC in the hamstrings during WBV. The highest levels of muscle activation were found at high frequencies and large amplitudes. Especially in the quadriceps femoris muscle, a WBV frequency of 30 Hz led to a significant increase in muscle activity compared to the other tested frequencies. However, it seems that knee angle is only relevant for the quadriceps femoris muscle. The results of this study should give more information for developing individual training protocols for WBV treatment in different practical applications

Dose-response effect of photobiomodulation therapy on neuromuscular economy during submaximal running.

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Dellagrana, Rodolfo André; Rossato, Mateus; Sakugawa, Raphael Luiz; Lazzari, Caetano Decian; Baroni, Bruno Manfredini; Diefenthaeler, Fernando

2018-02-01

The purpose of this study was to verify the photobiomodulation therapy (PBMT) effects with different doses on neuromuscular economy during submaximal running tests. Eighteen male recreational runners participate in a randomized, double-blind, and placebo-controlled trial, which each participant was submitted to the same testing protocol in five conditions: control, placebo, and PBMT with doses of 15, 30, and 60 J per site (14 sites in each lower limb). The submaximal running was performed at 8 and 9 km h -1 during 5 min for each velocity. Muscle activation of the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), biceps femoris (BF), and gastrocnemius lateralis (GL) was collected during the last minute of each running test. The root mean square (RMS) was normalized by maximal isometric voluntary contraction (MIVC) performed a priori in an isokinetic dynamometer. The RMS sum of all muscles (RMS LEG ) was considered as main neuromuscular economy parameter. PBMT with doses of 15, 30, and 60 J per site [33 diodes = 5 lasers (850 nm), 12 LEDs (670 nm), 8 LEDs (880 nm), and 8 LEDs (950 nm)] or placebo applications occurred before running tests. For the statistical analysis, the effect size was calculated. Moreover, a qualitative inference was used to determine the magnitude of differences between groups. Peak torque and RMS during MIVCs showed small effect sizes. According to magnitude-based inference, PBMT with dose of 15 J per site showed possibly and likely beneficial effects on neuromuscular economy during running at 8 and 9 km h -1 , respectively. On other hand, PBMT with doses of 30 and 60 J per site showed possible beneficial effects only during running at 9 km h -1 . We concluded that PBMT improve neuromuscular economy and the best PBMT dose was 15 J per site (total dose of 420 J).

Neuromuscular and muscle-tendon system adaptations to isotonic and isokinetic eccentric exercise.

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Guilhem, G; Cornu, C; Guével, A

2010-06-01

To present the properties of an eccentric contraction and compare neuromuscular and muscle-tendon system adaptations induced by isotonic and isokinetic eccentric trainings. An eccentric muscle contraction is characterized by the production of muscle force associated to a lengthening of the muscle-tendon system. This muscle solicitation can cause micro lesions followed by a regeneration process of the muscle-tendon system. Eccentric exercise is commonly used in functional rehabilitation for its positive effect on collagen synthesis but also for resistance training to increase muscle strength and muscle mass in athletes. Indeed, eccentric training stimulates muscle hypertrophy, increases the fascicle pennation angle, fascicles length and neural activation, thus inducing greater strength gains than concentric or isometric training programs. Eccentric exercise is commonly performed either against a constant external load (isotonic) or at constant velocity (isokinetic), inducing different mechanical constraints. These different mechanical constraints could induce structural and neural adaptive strategies specific to each type of exercise. The literature tends to show that isotonic mode leads to a greater strength gain than isokinetic mode. This observation could be explained by a greater neuromuscular activation after IT training. However, the specific muscle adaptations induced by each mode remain difficult to determine due to the lack of standardized, comparative studies. 2010 Elsevier Masson SAS. All rights reserved.

Kinesiotaping enhances the rate of force development but not the neuromuscular efficiency of physically active young men.

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Magalhães, Igor; Bottaro, Martim; Mezzarane, Rinaldo André; Neto, Frederico Ribeiro; Rodrigues, Bruno A; Ferreira-Júnior, João B; Carregaro, Rodrigo Luiz

2016-06-01

Investigations on the effects of KT on human performance have been increasing in the last few years. However, there is a paucity of studies investigating its effects on neuromuscular efficiency (NME) and rate of force development (RFD). To evaluate the NME and RFD of the soleus and gastrocnemius muscles in physically active individuals under KT application. Twenty young males (79.7±8.2kg; 1.78±0.05m; 24.7±4.4years) performed three conditions in a randomized order: (1) Baseline (BL, no tape); (2) Activation (ACTIKT, tape for muscle activation); and (3) Inhibition (INHIKT, tape for muscle inhibition). The tape was applied along the lateral and medial border of gastrocnemius with 30% tension for 48h. Peak torque (PT), RFD and NME were measured at BL and 48h after ACTIKT and INHIKT by performing a maximum isometric contraction. The RFD was significantly higher in ACTIKT compared to BL at 0-30 (P=0.010), 0-50 (P=0.008) and 0-100ms (P=0.007). The PT and NME did not differ among conditions (P>0.05). KT applied for muscle activation yielded a higher RFD during the initial phase of the muscle contraction. However, KT has no enhancement effect on NME and peak torque. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crimpy enables discrimination of presynaptic and postsynaptic pools of a BMP at the Drosophila neuromuscular junction.

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James, Rebecca E; Hoover, Kendall M; Bulgari, Dinara; McLaughlin, Colleen N; Wilson, Christopher G; Wharton, Kristi A; Levitan, Edwin S; Broihier, Heather T

2014-12-08

Distinct pools of the bone morphogenetic protein (BMP) Glass bottom boat (Gbb) control structure and function of the Drosophila neuromuscular junction. Specifically, motoneuron-derived Gbb regulates baseline neurotransmitter release, whereas muscle-derived Gbb regulates neuromuscular junction growth. Yet how cells differentiate between these ligand pools is not known. Here we present evidence that the neuronal Gbb-binding protein Crimpy (Cmpy) permits discrimination of pre- and postsynaptic ligand by serving sequential functions in Gbb signaling. Cmpy first delivers Gbb to dense core vesicles (DCVs) for activity-dependent release from presynaptic terminals. In the absence of Cmpy, Gbb is no longer associated with DCVs and is not released by activity. Electrophysiological analyses demonstrate that Cmpy promotes Gbb's proneurotransmission function. Surprisingly, the Cmpy ectodomain is itself released upon DCV exocytosis, arguing that Cmpy serves a second function in BMP signaling. In addition to trafficking Gbb to DCVs, we propose that Gbb/Cmpy corelease from presynaptic terminals defines a neuronal protransmission signal. Copyright © 2014 Elsevier Inc. All rights reserved.

Deep Neuromuscular Blockade Improves Laparoscopic Surgical Conditions

DEFF Research Database (Denmark)

Rosenberg, Jacob; Herring, W Joseph; Blobner, Manfred

2017-01-01

INTRODUCTION: Sustained deep neuromuscular blockade (NMB) during laparoscopic surgery may facilitate optimal surgical conditions. This exploratory study assessed whether deep NMB improves surgical conditions and, in doing so, allows use of lower insufflation pressures during laparoscopic cholecys...

Fatigue in neuromuscular disorders: Focus on Guillain-Barré syndrome and Pompe disease

NARCIS (Netherlands)

J.M. de Vries (Juna); M.L.C. Hagemans (Marloes); J.B.J. Bussmann (Hans); A.T. van der Ploeg (Ans); P.A. van Doorn (Pieter)

2010-01-01

textabstractFatigue accounts for an important part of the burden experienced by patients with neuromuscular disorders. Substantial high prevalence rates of fatigue are reported in a wide range of neuromuscular disorders, such as Guillain-Barré syndrome and Pompe disease. Fatigue can be subdivided

The immediate effect of neuromuscular joint facilitation on the rotation of the tibia during walking.

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Li, Desheng; Huang, Qiuchen; Huo, Ming; Hiiragi, Yukinobu; Maruyama, Hitoshi

2017-01-01

[Purpose] The aim of this study was to investigate the change in tibial rotation during walking among young adults after neuromuscular joint facilitation therapy. [Subjects and Methods] The subjects were twelve healthy young people (6 males, 6 females). A neuromuscular joint facilitation intervention and nonintervention were performed. The interventions were performed one after the other, separated by a 1-week interval. The order of the interventions was completely randomized. The rotation of the tibia during walking was evaluated before and after treatment. [Results] The neuromuscular joint facilitation group demonstrated increased lateral rotation of the tibia in the overall gait cycle and stance phase, and decreased medial rotation of the tibia in the overall gait cycle, stance phase, and swing phase after the neuromuscular joint facilitation intervention. In the control group, there were no significant differences. [Conclusion] These results suggest neuromuscular joint facilitation intervention has an immediate effect on the rotational function of the knee.

Comparing conventional physical therapy rehabilitation with neuromuscular electrical stimulation after TKA.

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Levine, Michael; McElroy, Karen; Stakich, Valerie; Cicco, Jodie

2013-03-01

Rehabilitation following total knee arthroplasty (TKA) is a costly, cumbersome, and often painful process. Physical therapy contributes to the successful outcome of TKA but can be expensive. Alternative methods of obtaining good functional results that help minimize costs are desirable. Neuromuscular electrical stimulation (NMES) is a potential option. Neuromuscular electrical stimulation has been shown to increase quadriceps muscle strength and activation following TKA. Functional scores also improve following TKA when NMES is added to conventional therapy protocols vs therapy alone. The authors hypothesized that rehabilitation managed by a physical therapist would not result in a functional advantage for patients undergoing TKA when compared with NMES and an unsupervised at-home range of motion exercise program and that patient satisfaction would not differ between the 2 groups. Seventy patients were randomized into a postoperative protocol of conventional physical therapy with a licensed therapist, including range of motion exercises and strengthening exercises, or into a program of NMES and range of motion exercises performed at home without therapist supervision. Noninferiority of the NMES program was obtained 6 weeks postoperatively (Knee Society pain/function scores, Western Ontario and McMaster Universities Osteoarthritis Index, flexion). Noninferiority was shown 6 months postoperatively for all parameters. The results suggest that rehabilitation managed by a physical therapist results in no functional advantage or difference in patient satisfaction when compared with NMES and an unsupervised at-home range of motion program. Neuromuscular electrical stimulation and unsupervised at-home range of motion exercises may provide an option for reducing the cost of the postoperative TKA recovery process without compromising quadriceps strength or patient satisfaction. Copyright 2013, SLACK Incorporated.

Redox homeostasis and age‐related deficits in neuromuscular integrity and function

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Lightfoot, Adam P.; Earl, Kate E.; Stofanko, Martin; McDonagh, Brian

2017-01-01

Abstract Skeletal muscle is a major site of metabolic activity and is the most abundant tissue in the human body. Age‐related muscle atrophy (sarcopenia) and weakness, characterized by progressive loss of lean muscle mass and function, is a major contributor to morbidity and has a profound effect on the quality of life of older people. With a continuously growing older population (estimated 2 billion of people aged >60 by 2050), demand for medical and social care due to functional deficits, associated with neuromuscular ageing, will inevitably increase. Despite the importance of this ‘epidemic’ problem, the primary biochemical and molecular mechanisms underlying age‐related deficits in neuromuscular integrity and function have not been fully determined. Skeletal muscle generates reactive oxygen and nitrogen species (RONS) from a variety of subcellular sources, and age‐associated oxidative damage has been suggested to be a major factor contributing to the initiation and progression of muscle atrophy inherent with ageing. RONS can modulate a variety of intracellular signal transduction processes, and disruption of these events over time due to altered redox control has been proposed as an underlying mechanism of ageing. The role of oxidants in ageing has been extensively examined in different model organisms that have undergone genetic manipulations with inconsistent findings. Transgenic and knockout rodent studies have provided insight into the function of RONS regulatory systems in neuromuscular ageing. This review summarizes almost 30 years of research in the field of redox homeostasis and muscle ageing, providing a detailed discussion of the experimental approaches that have been undertaken in murine models to examine the role of redox regulation in age‐related muscle atrophy and weakness. PMID:28744984

Direct and indirect measurement of neuromuscular fatigue in Canadian football players.

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Clarke, Nick; Farthing, Jonathan P; Lanovaz, Joel L; Krentz, Joel R

2015-05-01

This study assessed the effects of a fatiguing game simulation (G-Sim) on the balance of collegiate Canadian football players. The purpose of the study was to evaluate postural control as a potential tool for monitoring neuromuscular fatigue (NMF) in collision-based team sports. Fifteen male Canadian football players were recruited (mean±SD: age 21.8±1.6 years, weight 97.6±14.7 kg). Indirect NMF measures (postural sway and countermovement jump (CMJ)) were performed 24 h before (TBase), immediately before (TPre) and after (TPost), and 24 h (T24) and 48 h after (T48) a Canadian football G-Sim. Peak isometric knee extensor torque of a maximal voluntary contraction (MVC) and electrically evoked tetani at 20 Hz (P20) and 80 Hz (P80) were also recorded as direct NMF measures at TBase, TPre, TPost, and T48. At TPost, we observed significant declines in MVC, P20, and the MVC/P80 ratio (-15.3%, -15.7%, and -12.1%, respectively; n=12) along with reductions in CMJ takeoff velocity and peak power (-6.9% and -6.5%, respectively; n=12) and larger area of the center of pressure trajectory (95.2%; n=10) during a 60-s postural sway task. All variables were no longer different than baseline by T48. Acute neuromuscular impairment in this cohort is likely attributable to alterations in excitation-contraction coupling due to structural damage and central activation failure. Congruency between the direct and indirect measures of NMF suggests monitoring postural sway has the potential to identify both neuromuscular and somatosensory alterations induced by acute game-induced fatigue in collision-based team sports players.

Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration.

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Minamoto, Takehiro; Osaka, Mariko; Yaoi, Ken; Osaka, Naoyuki

2014-01-01

Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.

Ankles back in randomized controlled trial (ABrCt): braces versus neuromuscular exercises for the secondary prevention of ankle sprains. Design of a randomised controlled trial.

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Janssen, Kasper W; van Mechelen, Willem; Verhagen, Evert Alm

2011-09-27

Ankle sprains are the most common sports and physical activity related injury. There is extensive evidence that there is a twofold increased risk for injury recurrence for at least one year post injury. In up to 50% of all cases recurrences result in disability and lead to chronic pain or instability, requiring prolonged medical care. Therefore ankle sprain recurrence prevention in athletes is essential. This RCT evaluates the effect of the combined use of braces and neuromuscular training (e.g. proprioceptive training/sensorimotor training/balance training) against the individual use of either braces or neuromuscular training alone on ankle sprain recurrences, when applied to individual athletes after usual care. This study was designed as three way randomized controlled trial with one year follow-up. Healthy individuals between 12 and 70 years of age, who were actively participating in sports and who had sustained a lateral ankle sprain in the two months prior to inclusion, were eligible for inclusion. After subjects had finished ankle sprain treatment by means of usual care, they were randomised to any of the three study groups. Subjects in group 1 received an eight week neuromuscular training program, subjects in group 2 received a sports brace to be worn during all sports activities for the duration of one year, and group 3 received a combination of the neuromuscular training program and a sports brace to be worn during all sports activities for the duration of eight weeks. Outcomes were assessed at baseline and every month for 12 months therafter. The primary outcome measure was incidence of ankle sprain recurrences. Secondary outcome measures included the direct and indirect costs of recurrent injury, the severity of recurrent injury, and the residual complaints during and after the intervention. The ABrCt is the first randomized controlled trial to directly compare the secondary preventive effect of the combined use of braces and neuromuscular training

Effects of a single whole body cryotherapy (-110°C) bout on neuromuscular performance of the elbow flexors during isokinetic exercise.

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Ferreira-Junior, J B; Vieira, C A; Soares, S R S; Guedes, R; Rocha Junior, V A; Simoes, H G; Brown, L E; Bottaro, M

2014-12-01

It has been demonstrated that body cooling may decrease neuromuscular performance. However, the effect of a single session of whole body cryotherapy (-110°C) on neuromuscular performance has not been well documented. Thus, the aim of this study was to evaluate the effects of a single exposure of WBC on elbow flexor neuromuscular performance. Thirteen physically active, healthy young men (age=27.9±4.2 years, mass=79.4±9.7 kg, height=176.7±5.2 cm) were randomly exposed to 2 different experimental conditions separated by a minimum of 72 h: 1) whole body cryotherapy- 3 min at -110°C; 2) control- 3 min at 21°C. All subjects were tested for maximal isokinetic elbow flexion at 60°.s(-1) 30 min before and 10 min after each condition. There were no significant differences in peak torque, average power, total work or muscle activity between conditions. Peak torque was lower at post-test compared to pre-test in both conditions (F=6.58, p=0.025). However, there were no differences between pre-test and post-test for any other variables. These results indicate that strength specialists, athletic trainers and physical therapists might utilize whole body cryotherapy before training or rehabilitation without compromising neuromuscular performance of the elbow flexors. © Georg Thieme Verlag KG Stuttgart · New York.

Neuromuscular training injury prevention strategies in youth sport: a systematic review and meta-analysis.

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Emery, Carolyn A; Roy, Thierry-Olivier; Whittaker, Jackie L; Nettel-Aguirre, Alberto; van Mechelen, Willem

2015-07-01

Youth have very high participation and injury rates in sport. Sport is the leading cause of injury in youth. Sport injury reduces future participation in physical activity which adversely affects future health. Sport injury may lead to overweight/obesity and post-traumatic osteoarthritis. The objective of the systematic review and meta-analysis was to evaluate the efficacy of injury prevention neuromuscular training strategies in youth sport. Three electronic databases were systematically searched up to September 2014. Studies selected met the following criteria: original data; analytic prospective design; investigated a neuromuscular training prevention strategy intervention(s) and included outcomes for injury sustained during sport participation. Two authors assessed the quality of evidence using Downs and Black (DB) criteria. Meta-analyses including randomised controlled trials only (RCTs) to ensure study design homogeneity were completed for lower extremity and knee injury outcomes. Of 2504 potentially relevant studies, 25 were included. Meta-analysis revealed a combined preventative effect of neuromuscular training in reducing the risk of lower extremity injury (incidence rate ratio: IRR=0.64 (95% CI 0.49 to 0.84)). Though not statistically significant, the point estimate suggests a protective effect of such programmes in reducing the risk of knee injury (IRR=0.74 (95% CI 0.51 to 1.07)). There is evidence for the effectiveness of neuromuscular training strategies in the reduction of injury in numerous team sports. Lack of uptake and ongoing maintenance of such programmes is an ongoing concern. A focus on implementation is critical to influence knowledge, behaviour change and sustainability of evidence informed injury prevention practice. 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.

Neuromuscular Control Mechanisms During Single-Leg Jump Landing in Subacute Ankle Sprain Patients: A Case Control Study.

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Allet, Lara; Zumstein, Franziska; Eichelberger, Patric; Armand, Stéphane; Punt, Ilona M

2017-03-01

Optimal neuromuscular control mechanisms are essential for preparing, maintaining, and restoring functional joint stability during jump landing and to prevent ankle injuries. In subacute ankle sprain patients, neither muscle activity nor kinematics during jump landing has previously been assessed. To compare neuromuscular control mechanisms and kinematics between subacute ankle sprain patients and healthy persons before and during the initial contact phase of a 25-cm single-leg jump. Case-control study. University hospital. Fifteen patients with grade I or II acute ankle sprains were followed up after 4 weeks of conservative management not involving physical therapy. Subjects performed alternately 3 single-leg forward jumps of 25 cm (toe-to-heel distance) barefoot. Their results were compared with the data of 15 healthy subjects. Electromyographic (EMG) activity of the musculus (m.) gastrocnemius lateralis, m. tibialis anterior, and m. peroneus longus as well as kinematics for ankle, knee, and hip joint were recorded for pre-initial contact (IC) phase, post-initial contact phase, and reflex-induced phase. The results showed that EMG activity of the 3 muscles did not differ between ankle sprain patients (n = 15) and healthy persons (n = 15) for any of the analyzed time intervals (all P > .05). However, during the pre-IC phase, ankle sprain patients presented less plantar flexion, as well as during the post-IC phase after jump landing, compared to healthy persons (P ankle joint can lead to neuromuscular control mechanism disturbances through which functional instability might arise. III. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Proprioceptive Neuromuscular Facilitation (PNF): Its Mechanisms and Effects on Range of Motion and Muscular Function

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Hindle, Kayla B.; Whitcomb, Tyler J.; Briggs, Wyatt O.; Hong, Junggi

2012-01-01

Proprioceptive neuromuscular facilitation (PNF) is common practice for increasing range of motion, though little research has been done to evaluate theories behind it. The purpose of this study was to review possible mechanisms, proposed theories, and physiological changes that occur due to proprioceptive neuromuscular facilitation techniques. Four theoretical mechanisms were identified: autogenic inhibition, reciprocal inhibition, stress relaxation, and the gate control theory. The studies suggest that a combination of these four mechanisms enhance range of motion. When completed prior to exercise, proprioceptive neuromuscular facilitation decreases performance in maximal effort exercises. When this stretching technique is performed consistently and post exercise, it increases athletic performance, along with range of motion. Little investigation has been done regarding the theoretical mechanisms of proprioceptive neuromuscular facilitation, though four mechanisms were identified from the literature. As stated, the main goal of proprioceptive neuromuscular facilitation is to increase range of motion and performance. Studies found both of these to be true when completed under the correct conditions. These mechanisms were found to be plausible; however, further investigation needs to be conducted. All four mechanisms behind the stretching technique explain the reasoning behind the increase in range of motion, as well as in strength and athletic performance. Proprioceptive neuromuscular facilitation shows potential benefits if performed correctly and consistently. PMID:23487249

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

Science.gov (United States)

Fauroux, Brigitte; Khirani, Sonia

2014-08-01

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

Neuromuscular findings in thyroid dysfunction: a prospective clinical and electrodiagnostic study

Science.gov (United States)

Duyff, R.; Van den Bosch, J.; Laman, D; van Loon, B.-J. P.; Linssen, W.

2000-01-01

OBJECTIVES—To evaluate neuromuscular signs and symptoms in patients with newly diagnosed hypothyroidism and hyperthyroidism.
METHODS—A prospective cohort study was performed in adult patients with newly diagnosed thyroid dysfunction. Patients were evaluated clinically with hand held dynamometry and with electrodiagnosis. The clinical features of weakness and sensory signs and the biochemical data were evaluated during treatment.
RESULTS—In hypothyroid patients 79% had neuromuscular complaints, 38% had clinical weakness (manual muscle strength testing) in one or more muscle groups, 42% had signs of sensorimotor axonal neuropathy, and 29% had carpal tunnel syndrome. Serum creatine kinase did not correlate with weakness. After 1 year of treatment 13% of the patients still had weakness. In hyperthyroid patients 67% had neuromuscular symptoms, 62% had clinical weakness in at least one muscle group that correlated with FT4 concentrations, but not with serum CK. Nineteen per cent of the patients had sensory-motor axonal neuropathy and 0% had carpal tunnel syndrome. The neuromuscular signs developed rapidly, early in the course of the disorder and were severe, but resolved rapidly and completely during treatment (average time 3.6months).
CONCLUSIONS—Neuromuscular symptoms and signs were present in most patients. About 40% of the hypothyroid patients and 20% of the hyperthyroid patients had predominantly sensory signs of a sensorimotor axonal neuropathy early in the course of thyroid disease. Weakness in hyperthyroidism evolved rapidly at an early stage of the disorder and resolved completely during treatment, suggesting a functional muscle disorder. Hand held dynamometry is sensitive for the detection of weakness and for the clinical evaluation of treatment effects. Weakness in hypothyroidism is more difficult to treat, suggesting myopathy.

 PMID:10811699

Exercise Therapy in Spinobulbar Muscular Atrophy and Other Neuromuscular Disorders

DEFF Research Database (Denmark)

Dahlqvist, Julia Rebecka; Vissing, John

2016-01-01

There is no curative treatment for most neuromuscular disorders. Exercise, as a treatment for these diseases, has therefore received growing attention. When executed properly, exercise can maintain and improve health and reduce the risk of cardiovascular disease, obesity, and diabetes. In persons...... in patients with neuromuscular diseases associated with weakness and wasting. We review studies that have investigated different types of exercise in both myopathies and motor neuron diseases, with particular emphasis on training of persons affected by spinobulbar muscular atrophy (SBMA). Finally, we provide...

Neuromuscular function and fatigue resistance of the plantar flexors following short-term cycling endurance training

Directory of Open Access Journals (Sweden)

Martin eBehrens

2015-05-01

Full Text Available Previously published studies on the effect of short-term endurance training on the neuromuscular function of the plantar flexors have shown that the H-reflex elicited at rest and during weak voluntary contractions was increased following the training regime. However, these studies did not test H-reflex modulation during isometric maximum voluntary contraction (iMVC and did not incorporate a control group in their study design to compare the results of the endurance training group to individuals without the endurance training stimulus. Therefore, this randomized controlled study was directed to investigate the neuromuscular function of the plantar flexors at rest and during iMVC before and after eight weeks of cycling endurance training. Twenty-two young adults were randomly assigned to an intervention group and a control group. During neuromuscular testing, rate of torque development, isometric maximum voluntary torque and muscle activation were measured. Triceps surae muscle activation and tibialis anterior muscle co-activation were assessed by normalized root mean square of the EMG signal during the initial phase of contraction (0-100, 100-200 ms and isometric maximum voluntary contraction of the plantar flexors. Furthermore, evoked spinal reflex responses of the soleus muscle (H-reflex evoked at rest and during iMVC, V-wave, peak twitch torques induced by electrical stimulation of the posterior tibial nerve at rest and fatigue resistance were evaluated. The results indicate that the endurance training did not lead to a significant change in any variable of interest. Data of the present study conflict with the outcome of previously published studies that have found an increase in H-reflex excitability after endurance training. However, these studies had not included a control group in their study design as was the case here. It is concluded that short-term cycling endurance training does not necessarily enhance H-reflex responses and fatigue

Associations of leisure-time physical activity with balance and lower extremity strength: a validation of the neuromuscular part of the Physical Activity Pie.

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Lindström, Paula J; Suni, Jaana H; Nygård, Clas-Håkan

2009-07-01

The importance of neuromuscular-type exercise (NME) has been recognized in recent recommendations for public health. However, the knowledge on associations and dose response of different types of leisure-time physical activity (LTPA) with musculoskeletal fitness and health is incomplete. This study evaluated the validity of the NME recommendation for public health introduced by the Physical Activity Pie. Engagement in LTPA and health-related fitness were assessed in 2 consecutive studies with the same adult population age 30 to 69 years (n = 575). Cross-sectional associations between different LTPA types and motor and musculoskeletal fitness were examined by logistic-regression models. Engagement in NME was associated with good static and dynamic balance and lower extremity strength. The highest odds ratios (OR) were found between brisk NME and static balance (most vs least fit OR = 2.39, moderate vs least fit OR = 1.94) and brisk NME and leg strength (more vs least fit OR = 2.10). Some associations were also found between brisk aerobic exercise and good balance. This cross-sectional study suggests that the recommendation for NME in the Physical Activity Pie is valid in terms of balance and leg strength, the 2 major fitness factors related to mobility functioning, especially among aging adults.

Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration.

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Takehiro Minamoto

Full Text Available Different people make different responses when they face a frustrating situation: some punish others (extrapunitive, while others punish themselves (intropunitive. Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9 showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9 showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.

Seizures, refractory status epilepticus, and depolarization block as endogenous brain activities

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El Houssaini, Kenza; Ivanov, Anton I.; Bernard, Christophe; Jirsa, Viktor K.

2015-01-01

Epilepsy, refractory status epilepticus, and depolarization block are pathological brain activities whose mechanisms are poorly understood. Using a generic mathematical model of seizure activity, we show that these activities coexist under certain conditions spanning the range of possible brain activities. We perform a detailed bifurcation analysis and predict strategies to escape from some of the pathological states. Experimental results using rodent data provide support of the model, highlighting the concept that these pathological activities belong to the endogenous repertoire of brain activities.

Preventing Ischial Pressure Ulcers: III. Clinical Pilot Study of Chronic Neuromuscular Electrical Stimulation

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Hilton M. Kaplan

2011-01-01

Full Text Available Objective: BIONs™ (BIOnic Neurons are injectable, wireless microstimulators that make chronic BION Active Seating (BAS possible for pressure ulcer prevention (PUP. Neuromuscular electrical stimulation (NMES produces skeletal motion and activates trophic factors, counteracting three major etiological mechanisms leading to pressure ulcers (PUs: immobility, soft-tissue atrophy, and ischemia. Companion papers I and II reviewed prior experience with NMES for PUP, and analyzed the biomechanical considerations, respectively. This paper presents a treatment strategy derived from this analysis, and the clinical results of the first three cases.

Sugammadex for reversal of neuromuscular blockade: a retrospective analysis of clinical outcomes and cost-effectiveness in a single center

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Carron M

2016-02-01

Full Text Available Michele Carron, Fabio Baratto, Francesco Zarantonello, Carlo Ori Department of Medicine, Anesthesiology and Intensive Care, University of Padova, Padova, Italy Objective: The aim of the study is to evaluate the clinical and economic impact of introducing a rocuronium–neostigmine–sugammadex strategy into a cisatracurium–neostigmine regimen for neuromuscular block (NMB management. Methods: We conducted a retrospective analysis of clinical outcomes and cost-effectiveness in five operating rooms at University Hospital of Padova. A clinical outcome evaluation after sugammadex administration as first-choice reversal drug in selected patients (rocuronium–sugammadex and as rescue therapy after neostigmine reversal (rocuronium–neostigmine–sugammadex compared to control was performed. A cost-analysis of NMB management accompanying the introduction of a rocuronium–neostigmine–sugammadex strategy into a cisatracurium–neostigmine regimen was carried out. To such purpose, two periods were compared: 2011–2012, without sugammadex available; 2013–2014, with sugammadex available. A subsequent analysis was performed to evaluate if sugammadex replacing neostigmine as first choice reversal drug is cost-effective. Results: The introduction of a rocuronium–neostigmine–sugammadex strategy into a cisatracurium–neostigmine regimen reduced the average cost of NMB management by 36%, from €20.8/case to €13.3/case. Patients receiving sugammadex as a first-choice reversal drug (3% exhibited significantly better train-of-four ratios at extubation (P<0.001 and were discharged to the surgical ward (P<0.001 more rapidly than controls. The cost-saving of sugammadex as first-choice reversal drug has been estimated to be €2.9/case. Patients receiving sugammadex as rescue therapy after neostigmine reversal (3.2% showed no difference in time to discharge to the surgical ward (P=0.44 compared to controls. No unplanned intensive care unit (ICU

Architectural properties of the neuromuscular compartments in selected forearm skeletal muscles.

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Liu, An-Tang; Liu, Ben-Li; Lu, Li-Xuan; Chen, Gang; Yu, Da-Zhi; Zhu, Lie; Guo, Rong; Dang, Rui-Shan; Jiang, Hua

2014-07-01

The purposes f this study were to (i) explore the possibility of splitting the selected forearm muscles into separate compartments in human subjects; (ii) quantify the architectural properties of each neuromuscular compartment; and (iii) discuss the implication of these properties in split tendon transfer procedures. Twenty upper limbs from 10 fresh human cadavers were used in this study. Ten limbs of five cadavers were used for intramuscular nerve study by modified Sihler's staining technique, which confirmed the neuromuscular compartments. The other 10 limbs were included for architectural analysis of neuromuscular compartments. The architectural features of the compartments including muscle weight, muscle length, fiber length, pennation angle, and sarcomere length were determined. Physiological cross-sectional area and fiber length/muscle length ratio were calculated. Five of the selected forearm muscles were ideal candidates for splitting, including flexor carpi ulnaris, flexor carpi radials, extensor carpi radialis brevis, extensor carpi ulnaris and pronator teres. The humeral head of pronator teres contained the longest fiber length (6.23 ± 0.31 cm), and the radial compartment of extensor carpi ulnaris contained the shortest (2.90 ± 0.28 cm). The ulnar compartment of flexor carpi ulnaris had the largest physiological cross-sectional area (5.17 ± 0.59 cm(2)), and the ulnar head of pronator teres had the smallest (0.67 ± 0.06 cm(2)). Fiber length/muscle length ratios of the neuromuscular compartments were relatively low (average 0.27 ± 0.09, range 0.18-0.39) except for the ulnar head of pronator teres, which had the highest one (0.72 ± 0.05). Using modified Sihler's technique, this research demonstrated that each compartment of these selected forearm muscles has its own neurovascular supply after being split along its central tendon. Data of the architectural properties of each neuromuscular compartment provide insight into the 'design' of their

Architectural properties of the neuromuscular compartments in selected forearm skeletal muscles

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Liu, An-Tang; Liu, Ben-Li; Lu, Li-Xuan; Chen, Gang; Yu, Da-Zhi; Zhu, Lie; Guo, Rong; Dang, Rui-Shan; Jiang, Hua

2014-01-01

The purposes f this study were to (i) explore the possibility of splitting the selected forearm muscles into separate compartments in human subjects; (ii) quantify the architectural properties of each neuromuscular compartment; and (iii) discuss the implication of these properties in split tendon transfer procedures. Twenty upper limbs from 10 fresh human cadavers were used in this study. Ten limbs of five cadavers were used for intramuscular nerve study by modified Sihler's staining technique, which confirmed the neuromuscular compartments. The other 10 limbs were included for architectural analysis of neuromuscular compartments. The architectural features of the compartments including muscle weight, muscle length, fiber length, pennation angle, and sarcomere length were determined. Physiological cross-sectional area and fiber length/muscle length ratio were calculated. Five of the selected forearm muscles were ideal candidates for splitting, including flexor carpi ulnaris, flexor carpi radials, extensor carpi radialis brevis, extensor carpi ulnaris and pronator teres. The humeral head of pronator teres contained the longest fiber length (6.23 ± 0.31 cm), and the radial compartment of extensor carpi ulnaris contained the shortest (2.90 ± 0.28 cm). The ulnar compartment of flexor carpi ulnaris had the largest physiological cross-sectional area (5.17 ± 0.59 cm2), and the ulnar head of pronator teres had the smallest (0.67 ± 0.06 cm2). Fiber length/muscle length ratios of the neuromuscular compartments were relatively low (average 0.27 ± 0.09, range 0.18–0.39) except for the ulnar head of pronator teres, which had the highest one (0.72 ± 0.05). Using modified Sihler's technique, this research demonstrated that each compartment of these selected forearm muscles has its own neurovascular supply after being split along its central tendon. Data of the architectural properties of each neuromuscular compartment provide insight into the ‘design’ of their

Electrophysiological study in neuromuscular junction disorders

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Ajith Cherian

2013-01-01

Full Text Available This review is on ultrastructure and subcellular physiology at normal and abnormal neuromuscular junctions. The clinical and electrophysiological findings in myasthenia gravis, Lambert-Eaton myasthenic syndrome (LEMS, congenital myasthenic syndromes, and botulinum intoxication are discussed. Single fiber electromyography (SFEMG helps to explain the basis of testing neuromuscular junction function by repetitive nerve stimulation (RNS. SFEMG requires skill and patience and its availability is limited to a few centers. For RNS supramaximal stimulation is essential and so is display of the whole waveform of each muscle response at maximum amplitude. The amplitudes of the negative phase of the first and fourth responses are measured from baseline to negative peak, and the percent change of the fourth response compared with the first represents the decrement or increment. A decrement greater than 10% is accepted as abnormal and smooth progression of response amplitude train and reproducibility form the crux. In suspected LEMS the effect of fast rates of stimulation should be determined after RNS response to slow rates of stimulation. Caution is required to avoid misinterpretation of potentiation and pseudofacilitation.

An adaptive neuromuscular controller for assistive lower-limb exoskeletons : A preliminary study on subjects with spinal cord injury

NARCIS (Netherlands)

Wu, Amy R.; Dzeladini, Florin; Brug, Tycho J.H.; Tamburella, Federica; Tagliamonte, Nevio L.; Van Asseldonk, Edwin H.F.; van der Kooij, H.; Ijspeert, Auke J.

2017-01-01

Versatility is important for a wearable exoskeleton controller to be responsive to both the user and the environment. These characteristics are especially important for subjects with spinal cord injury (SCI), where active recruitment of their own neuromuscular system could promote motor recovery.

An adaptive neuromuscular controller for assistive lower-limb exoskeletons : A preliminary study on subjects with spinal cord injury

NARCIS (Netherlands)

Wu, Amy R.; Dzeladini, Florin; Brug, Tycho J.H.; Tamburella, Federica; Tagliamonte, Nevio L.; Van Asseldonk, Edwin H.F.; Van Der Kooij, Herman; IJspeert, Auke Jan

2017-01-01

Versatility is important for a wearable exoskeleton controller to be responsive to both the user and the environment. These characteristics are especially important for subjects with spinal cord injury (SCI), where active recruitment of their own neuromuscular system could promote motor recovery.

[Impact of a quality assurance program on the use of neuromuscular monitoring and reversal of muscle relaxants].

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Motamed, C; Bourgain, J-L

2009-04-01

As part of a quality assurance in the anaesthesia department, this study was designed to enhance the rate of neuromuscular blockade monitoring for patients receiving muscle relaxant during anaesthesia. After approval of our local ethical committee, we assessed 200 computerized anaesthesia records in which neuromuscular relaxants were used. The following data were collected: demographic characteristics, durations of anaesthesia and surgery, use of neuromuscular monitoring, reversal agents and the quality of neuromuscular monitoring. The results were discussed with all anaesthesia providers of the department and an internal guideline was elaborated with the endpoint that all patients having muscle relaxants should have quantitative neuromuscular monitoring. Six months later, another assessment of 200 consecutive records collected the same data to check the efficiency of the elaborated guideline. The monitoring rate was of 67% at the first assessment and increased to 94% (passessment and was stable at the second assessment (50%). The rate of patients not monitored and not reversed decreased from 5 to 2% (pquality assurance program systematic quantitative monitoring of neuromuscular blockade can be significantly increased.

Effects of neuromuscular joint facilitation on bridging exercises with respect to deep muscle changes.

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Zhou, Bin; Huang, QiuChen; Zheng, Tao; Huo, Ming; Maruyama, Hitoshi

2015-05-01

[Purpose] This study examined the effects of neuromuscular joint facilitation on bridging exercises by assessing the cross-sectional area of the multifidus muscle and thickness of the musculus transversus abdominis. [Subjects] Twelve healthy men. [Methods] Four exercises were evaluated: (a) supine resting, (b) bridging resistance exercise involving posterior pelvic tilting, (c) bridging resistance exercise involving anterior pelvic tilting, and (d) bridging resistance exercise involving neuromuscular joint facilitation. The cross-sectional area of the multifidus muscle and thickness of the musculus transversus abdominis were measured during each exercise. [Results] The cross-sectional area of the multifidus muscle and thickness of the musculus transversus abdominis were significantly greater in the neuromuscular joint facilitation group than the others. [Conclusion] Neuromuscular joint facilitation intervention improves the function of deep muscles such as the multifidus muscle and musculus transversus abdominis. Therefore, it can be recommended for application in clinical treatments such as that for back pain.

The Role of Neuromuscular Changes in Aging and Knee Osteoarthritis on Dynamic Postural Control

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Takacs, Judit; Carpenter, Mark G.; Garland, S. Jayne; Hunt, Michael A.

2013-01-01

Knee osteoarthritis (OA) is a chronic joint condition, with 30% of those over the age of 75 exhibiting severe radiographic disease. Nearly 50% of those with knee OA have experienced a fall in the past year. Falls are a considerable public health concern, with a high risk of serious injury and a significant socioeconomic impact. The ability to defend against a fall relies on adequate dynamic postural control, and alterations in dynamic postural control are seen with normal aging. Neuromuscular changes associated with aging may be responsible for some of these alterations in dynamic postural control. Even greater neuromuscular deficits, which may impact dynamic postural control and the ability to defend against a fall, are seen in people with knee OA. There is little evidence to date on how knee OA affects the ability to respond to and defend against falls and the neuromuscular changes that contribute to balance deficits. As a result, this review will: summarize the key characteristics of postural responses to an external perturbation, highlight the changes in dynamic postural control seen with normal aging, review the neuromuscular changes associated with aging that have known and possible effects on dynamic postural control, and summarize the neuromuscular changes and balance problems in knee OA. Future research to better understand the role of neuromuscular changes in knee OA and their effect on dynamic postural control will be suggested. Such an understanding is critical to the successful creation and implementation of fall prevention and treatment programs, in order to reduce the excessive risk of falling in knee OA. PMID:23696951

Fatty replacement of lower paraspinal muscles: normal and neuromuscular disorders

International Nuclear Information System (INIS)

Hader, H.; Gadoth, N.; Heifetz, H.

1983-01-01

The physiologic replacement of the lower paraspinal muscles by fat was evaluated in 157 patients undergoing computed tomography for reasons unrelated to abnormalities of the locomotor system. Five patients with neuromuscular disorders were similarly evaluated. The changes were graded according to severity at three spinal levels: lower thoracic-upper lumbar, midlumbar, and lumbosacral. The results were analyzed in relation to age and gender. It was found that fatty replacement of paraspinal muscles is a normal age-progressive phenomenon most prominent in females. It progresses down the spine, being most advanced in the lumbosacral region. The severest changes in the five patients with neuromuscular disorders (three with poliomyelitis and two with progressive muscular dystrophy) consisted of complete muscle group replacement by fat. In postpoliomyelitis atrophy, the distribution was typically asymmetric and sometimes lacked clinical correlation. In muscular dystrophy, fatty replacement was symmetric, showing relative sparing of the psoas and multifidus muscles. In patients with neuromuscular diseases, computed tomography of muscles may be helpful in planning a better rehabilitation regimen

Fatty replacement of lower paraspinal muscles: normal and neuromuscular disorders

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Hader, H.; Gadoth, N.; Heifetz, H.

1983-11-01

The physiologic replacement of the lower paraspinal muscles by fat was evaluated in 157 patients undergoing computed tomography for reasons unrelated to abnormalities of the locomotor system. Five patients with neuromuscular disorders were similarly evaluated. The changes were graded according to severity at three spinal levels: lower thoracic-upper lumbar, midlumbar, and lumbosacral. The results were analyzed in relation to age and gender. It was found that fatty replacement of paraspinal muscles is a normal age-progressive phenomenon most prominent in females. It progresses down the spine, being most advanced in the lumbosacral region. The severest changes in the five patients with neuromuscular disorders (three with poliomyelitis and two with progressive muscular dystrophy) consisted of complete muscle group replacement by fat. In postpoliomyelitis atrophy, the distribution was typically asymmetric and sometimes lacked clinical correlation. In muscular dystrophy, fatty replacement was symmetric, showing relative sparing of the psoas and multifidus muscles. In patients with neuromuscular diseases, computed tomography of muscles may be helpful in planning a better rehabilitation regimen.

Effects of sugammadex on incidence of postoperative residual neuromuscular blockade: a randomized, controlled study.

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Brueckmann, B; Sasaki, N; Grobara, P; Li, M K; Woo, T; de Bie, J; Maktabi, M; Lee, J; Kwo, J; Pino, R; Sabouri, A S; McGovern, F; Staehr-Rye, A K; Eikermann, M

2015-11-01

This study aimed to investigate whether reversal of rocuronium-induced neuromuscular blockade with sugammadex reduced the incidence of residual blockade and facilitated operating room discharge readiness. Adult patients undergoing abdominal surgery received rocuronium, followed by randomized allocation to sugammadex (2 or 4 mg kg(-1)) or usual care (neostigmine/glycopyrrolate, dosing per usual care practice) for reversal of neuromuscular blockade. Timing of reversal agent administration was based on the providers' clinical judgement. Primary endpoint was the presence of residual neuromuscular blockade at PACU admission, defined as a train-of-four (TOF) ratio sugammadex patients and 33 out of 76 (43.4%) usual care patients had TOF-Watch SX-assessed residual neuromuscular blockade at PACU admission (odds ratio 0.0, 95% CI [0-0.06], Psugammadex vs usual care (14.7 vs. 18.6 min respectively; P=0.02). After abdominal surgery, sugammadex reversal eliminated residual neuromuscular blockade in the PACU, and shortened the time from start of study medication administration to the time the patient was ready for discharge from the operating room. Clinicaltrials.gov:NCT01479764. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An evidence-based review of hip-focused neuromuscular exercise interventions to address dynamic lower extremity valgus

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Ford KR

2015-08-01

Full Text Available Kevin R Ford,1 Anh-Dung Nguyen,2 Steven L Dischiavi,1 Eric J Hegedus,1 Emma F Zuk,2 Jeffrey B Taylor11Department of Physical Therapy, High Point University, High Point, NC, USA; 2Department of Athletic Training, School of Health Sciences, High Point University, High Point, NC, USAAbstract: Deficits in proximal hip strength or neuromuscular control may lead to dynamic lower extremity valgus. Measures of dynamic lower extremity valgus have been previously shown to relate to increased risk of several knee pathologies, specifically anterior cruciate ligament ruptures and patellofemoral pain. Therefore, hip-focused interventions have gained considerable attention and been successful in addressing these knee pathologies. The purpose of the review was to identify and discuss hip-focused exercise interventions that aim to address dynamic lower extremity valgus. Previous electromyography, kinematics, and kinetics research support the use of targeted hip exercises with non-weight-bearing, controlled weight-bearing, functional exercise, and, to a lesser extent, dynamic exercises in reducing dynamic lower extremity valgus. Further studies should be developed to identify and understand the mechanistic relationship between optimized biomechanics during sports and hip-focused neuromuscular exercise interventions.Keywords: dynamic lower extremity valgus, hip neuromuscular control, ACL injury rehabilitation, patellofemoral pain, hip muscular activation

Caffeine ingestion reverses the circadian rhythm effects on neuromuscular performance in highly resistance-trained men.

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Ricardo Mora-Rodríguez

Full Text Available PURPOSE: To investigate whether caffeine ingestion counteracts the morning reduction in neuromuscular performance associated with the circadian rhythm pattern. METHODS: Twelve highly resistance-trained men underwent a battery of neuromuscular tests under three different conditions; i morning (10:00 a.m. with caffeine ingestion (i.e., 3 mg kg(-1; AM(CAFF trial; ii morning (10:00 a.m. with placebo ingestion (AM(PLAC trial; and iii afternoon (18:00 p.m. with placebo ingestion (PM(PLAC trial. A randomized, double-blind, crossover, placebo controlled experimental design was used, with all subjects serving as their own controls. The neuromuscular test battery consisted in the measurement of bar displacement velocity during free-weight full-squat (SQ and bench press (BP exercises against loads that elicit maximum strength (75% 1RM load and muscle power adaptations (1 m s(-1 load. Isometric maximum voluntary contraction (MVC(LEG and isometric electrically evoked strength of the right knee (EVOK(LEG were measured to identify caffeine's action mechanisms. Steroid hormone levels (serum testosterone, cortisol and growth hormone were evaluated at the beginning of each trial (PRE. In addition, plasma norepinephrine (NE and epinephrine were measured PRE and at the end of each trial following a standardized intense (85% 1RM 6 repetitions bout of SQ (POST. RESULTS: In the PM(PLAC trial, dynamic muscle strength and power output were significantly enhanced compared with AM(PLAC treatment (3.0%-7.5%; p≤0.05. During AM(CAFF trial, muscle strength and power output increased above AM(PLAC levels (4.6%-5.7%; p≤0.05 except for BP velocity with 1 m s(-1 load (p = 0.06. During AM(CAFF, EVOK(LEG and NE (a surrogate of maximal muscle sympathetic nerve activation were increased above AM(PLAC trial (14.6% and 96.8% respectively; p≤0.05. CONCLUSIONS: These results indicate that caffeine ingestion reverses the morning neuromuscular declines in highly resistance

Possible applications of Neuromuscular Taping in pain reduction in Multiple Sclerosis subject: a preliminary report

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Carmine Berlingieri

2016-12-01

Full Text Available Pain is a common disabling symptom in patients with Multiple Sclerosis (MS. It has been indicated that pain prevalence in MS patients is between 29–86 %. It is evident that most MS patients requiring treatment will be also searching pain related treatments to assist in day to day activities. Neuropathic pain is a difficult symptom and is generally inadequately relieved even though different rehabilitative approaches may be used. Neuromuscular Taping inducing micro-movements by stimulating receptors in the skin has been described in literature as a possible intervention in neurological and orthopedic rehabilitation improving mobility and in pain reduction. The aim of this preliminary report was to analyze the effect and to evaluate the possible applications of Neuromuscular Taping (NMT in patients with MS in order to reduce pain in comparison to the Transcutaneous Electrical Nerve Stimulation (TENS and to physical rehabilitation treatment alone. We observed that NMT together with standard physical rehabilitation was able to reduce neuropathic pain to greater lengths, with statistically significant differences between pre and post treatment, compared to the other treatments evaluated. This study showed increased efficacy in pain reduction when NMT was applied to standard physical treatment in long standing pain conditions. Neuromuscular Taping may constitute a low cost treatment strategy for neuropathic pain conditions in MS.

Ankles back in randomized controlled trial (ABrCt: braces versus neuromuscular exercises for the secondary prevention of ankle sprains. Design of a randomised controlled trial

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Verhagen Evert ALM

2011-09-01

Full Text Available Abstract Background Ankle sprains are the most common sports and physical activity related injury. There is extensive evidence that there is a twofold increased risk for injury recurrence for at least one year post injury. In up to 50% of all cases recurrences result in disability and lead to chronic pain or instability, requiring prolonged medical care. Therefore ankle sprain recurrence prevention in athletes is essential. This RCT evaluates the effect of the combined use of braces and neuromuscular training (e.g. proprioceptive training/sensorimotor training/balance training against the individual use of either braces or neuromuscular training alone on ankle sprain recurrences, when applied to individual athletes after usual care. Methods/Design This study was designed as three way randomized controlled trial with one year follow-up. Healthy individuals between 12 and 70 years of age, who were actively participating in sports and who had sustained a lateral ankle sprain in the two months prior to inclusion, were eligible for inclusion. After subjects had finished ankle sprain treatment by means of usual care, they were randomised to any of the three study groups. Subjects in group 1 received an eight week neuromuscular training program, subjects in group 2 received a sports brace to be worn during all sports activities for the duration of one year, and group 3 received a combination of the neuromuscular training program and a sports brace to be worn during all sports activities for the duration of eight weeks. Outcomes were assessed at baseline and every month for 12 months therafter. The primary outcome measure was incidence of ankle sprain recurrences. Secondary outcome measures included the direct and indirect costs of recurrent injury, the severity of recurrent injury, and the residual complaints during and after the intervention. Discussion The ABrCt is the first randomized controlled trial to directly compare the secondary preventive

Tilted seat position for non-ambulant individuals with neurological and neuromuscular impairment: a systematic review.

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Michael, S M; Porter, D; Pountney, T E

2007-12-01

To determine the effects of tilt-in-space seating on outcomes for people with neurological or neuromuscular impairment who cannot walk. Search through electronic databases (MEDLINE, Embase, CINAHL, AMED). Discussions with researchers who are active in field. Selection criteria included interventional studies that investigated the effects of seat tilt on outcome or observational studies that identified outcomes for those who had used tilt-in-space seating in populations with neurological or neuromuscular impairments. Two reviewers independently selected trials for inclusion, assessed quality and extracted data. Nineteen studies were identified which fulfilled the selection criteria. Seventeen of these were essentially before-after studies investigating the immediate effects of tilting the seating. All studies looked at populations with neurological impairment, and most were on children with cerebral palsy (n=8) or adults with spinal cord injury (n=8). REVIEWER'S CONCLUSION: Posterior tilt can reduce pressures at the interface under the pelvis.

Sugammadex facilitates early recovery after surgery even in the absence of neuromuscular monitoring in patients undergoing laryngeal microsurgery: a single-center retrospective study.

Science.gov (United States)

Park, Eui-Seok; Lim, Byung Gun; Lee, Won-Joon; Lee, Il Ok

2016-08-02

In many countries, routine clinical anaesthesia does not always involve neuromuscular monitoring. In these clinical settings, the efficacy and safety of sugammadex use has not yet been confirmed. We investigated the efficacy and safety of sugammadex in the absence of neuromuscular monitoring. One hundred and forty patients who underwent laryngeal microsurgery with the use of rocuronium as a neuromuscular blocking agent, without the use of a neuromuscular monitoring device, were retrospectively investigated. The patients were randomly chosen among all the patients who met the inclusion criteria at a tertiary university hospital between July 2013 and February 2015 and were allocated to group S (sugammadex group) or group P (pyridostigmine group) according to the neuromuscular reversal agent administered. Five patients were excluded from analysis and 135 patients completed the study. Primary outcome was extubation time. Secondary outcomes were anaesthesia time, the correlation between anaesthesia time and extubation time, the total amount of rocuronium, and postoperative adverse events in the post-anaesthesia care unit (PACU). Extubation time was significantly shorter in group S (6.3 ± 3.9 min) than in group P (9.0 ± 5.4 min). Anaesthesia time was also significantly shorter in group S (30.7 ± 10.3 min) than in group P (35.8 ± 12.6 min). In the patients with an anaesthesia time of 30 min or less, there was a positive correlation between anaesthesia time and extubation time in group P (r = 0.453), but there was no significant relationship in group S. The total amount of rocuronium used was higher in group S (0.62 ± 0.11 mg kg(-1)) than in group P (0.38 ± 0.14 mg kg(-1)). Postoperative adverse events in the PACU were comparable between the groups, except for tachycardia events: the incidence of tachycardia was significantly lower in group S (8.0 %) than in group P (17.3 %). Sugammadex could shorten anaesthesia and extubation

Evaluation of skeletal muscular involvement in neuromuscular disorders with thallium-201 whole body scintigraphy

International Nuclear Information System (INIS)

Yamamoto, Shuhei; Sotobata, Iwao; Indo, Toshikatsu; Matsuoka, Yukihiko; Matsushima, Hideo; Suzuki, Akio; Abe, Tetsutaro; Sakuma, Sadayuki

1986-01-01

The extent as well as severity of pathologic changes of skeletal muscles were analyzed with thallium-201 whole body scintigraphy (WBS) in 29 cases of various types of neuromuscular diseases (18 cases of myogenic and 11 cases of neurogenic muscular diseases) and 14 cases of normal controls. After intravenous injection of 2 mCi of thallium-201 chloride, WBS was performed for 15 minutes using a gamma camera with twin-opposed large rectangular detectors. Counts at brachia, forearms, thighs, and calves were assessed after reconstruction of the scintigram of the whole body by taking the geometric mean of the anterior and posterior data. WBS showed uniform tracer activities in the 4 extremities in 12 cases among 14 controls. Laterality in distribution of counts of both legs and arms was noted in the remaining 2 controls. WBS revealed decrease of perfusion in the extremities with muscular atrophy and/or weakness in neuromuscular diseases. The overall diagnostic accuracy of WBS for evaluation of skeletal muscle involvement was 75 to 80 % except for the bilateral brachia for which it decreased to 65 %. All of the three cases of muscular dystrophy with pseudohypertrophy of the calves or thighs showed unequivocal decrease of perfusion of those regions in WBS. In conclusion, thallium-201 WBS was considered to be a useful clinical means in evaluating the extent and severity of muscular involvement of various types of neuromuscular disorders. (author)

Neuromuscular signs associated with acute hypophosphatemia in a dog.

Science.gov (United States)

Claus, Kimberly N; Day, Thomas K; Wolf, Christina

2015-01-01

The purpose of this report was to describe the successful recognition and management of neuromuscular dysfunction secondary to severe, acute hypophosphatemia in an adult dog with a 2 day history of vomiting, anorexia, and abdominal pain. Radiographs were suggestive of a foreign body obstruction, and surgery was recommended. Resection and anastomosis of the distal duodenum and proximal jejunum was performed. The dog recovered uneventfully, but approximately 36 hr postoperatively, he was found to have significant weakness and muscle tremors that were accompanied by hyperthermia. The only significant abnormality on a serum biochemical profile was a phosphorous level of 0.26 mmol/L. Within 6 hr of initiating phosphorous supplementation, the patient fully recovered and had no residual signs of neuromuscular dysfunction. Signs of neurologic dysfunction secondary to hypophosphatemia are commonly recognized in human patients. Reports of patients with severe muscle weakness, some of which necessitate ventilation due to weakening of muscles of respiration, are common throughout the literature. Less commonly, tremors are noted. This is the first known report of neuromuscular signs recognized and rapidly corrected in a dog. Although it is likely to be uncommon, hypophosphatemia should be recognized as a differential diagnosis in patients with tremors and/or muscle weakness.

Effects of aquatic balance training and detraining on neuromuscular performance and balance in healthy middle aged male

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Ali Abbasi

2012-04-01

Full Text Available Introduction: Since disorders in neuromuscular performance and imbalance are the main cause of fallingamong the middle aged, their aspects including rehabilitation of balance are the main concern theresearchers attend to them. The aim of this study was to determine the effects of eight weeks aquaticbalance training (ABT and detraining on neuromuscular performance and balance in healthy middle agedmale.Materials and Methods: Thirty adult male subjects were randomized into two groups of ABT and control(n=15 per group. Berg balance scale, Timed Up and Go and 5-Chair stand tests, as they are indicators ofbalance and neuromuscular performance in older subjects, were taken as pretest and post-test and after four,six, and eight weeks of detraining as well. The ABT consisted of the sessions that lasted one hour, threetimes a week, for eight weeks.Results: Results showed that neuromuscular performance and balance improved significantly in ABTgroup (P 0.05.Conclusion: ABT can affect neuromuscular performance and balance in healthy middle aged male, andreduce the probability of falling among them. Moreover, the effects of these training are persistent afterdetraining periods. Hence, ABT can be recommended as an effective neuromuscular and balance training inhealthy middle aged male

Two novel mutations in the BCHE gene in patients with prolonged duration of action of mivacurium or succinylcholine during anaesthesia

DEFF Research Database (Denmark)

Gätke, Mona R; Bundgaard, Jens R; Viby-Mogensen, Jørgen

2007-01-01

Butyrylcholinesterase (BChE) hydrolyses the neuromuscular blocking agents, succinylcholine and mivacurium used during general anaesthesia. Hereditary low BChE activity may result in an extensively prolonged duration of action of these drugs, especially in patients who are homozygous for the atypi......Butyrylcholinesterase (BChE) hydrolyses the neuromuscular blocking agents, succinylcholine and mivacurium used during general anaesthesia. Hereditary low BChE activity may result in an extensively prolonged duration of action of these drugs, especially in patients who are homozygous...... for the atypical or silent variants. We present three novel mutations in the butyrylcholinesterase gene (BCHE) identified in three families in which a member had experienced severely prolonged duration of action of succinylcholine....

Staurosporine potentiates platelet activating factor stimulated phospholipase C activity in rabbit platelets but does not block desensitization by platelet activating factor

International Nuclear Information System (INIS)

Morrison, W.J.; Dhar, A.; Shukla, S.D.

1989-01-01

The possible involvement of protein kinase C activation in regulating PAF-stimulated PLC activity was studied in rabbit platelets. PAF stimulated incorporation of 32 P into proteins and caused [ 3 H]InsP 3 levels to increase about 260% of control. These responses were compared after platelets were pretreated with either PAF, phorbol 12-myristate 13-acetate (PMA) or staurosporine and also after pretreatments with staurosporine followed by PAF or PMA. Pretreating platelets with staurosporine potentiated PAF-stimulated [ 3 H]InsP 3 levels by 54% and blocked protein phosphorylation. Pretreatments with PAF and PMA caused PAF-stimulated [ 3 H]InsP 3 levels to decrease to 115 and 136%, respectively. Staurosporine pretreatment blocked the decrease caused by the PMA pretreatment but not that by PAF. This study demonstrates that PAF-stimulated PLC activity is negatively affected by protein kinase C (PKC) activation and that inhibition of PKC activity did not prevent desensitization of PLC by PAF

Hybrid neuroprosthesis for the upper limb: combining brain-controlled neuromuscular stimulation with a multi-joint arm exoskeleton

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Florian Grimm

2016-08-01

Full Text Available Brain-machine interface-controlled (BMI neurofeedback training aims to modulate cortical physiology and is applied during neurorehabilitation to increase the responsiveness of the brain to subsequent physiotherapy. In a parallel line of research, robotic exoskeletons are used in goal-oriented rehabilitation exercises for patients with severe motor impairment to extend their range of motion and the intensity of training. Furthermore, neuromuscular electrical stimulation (NMES is applied in neurologically impaired patients to restore muscle strength by closing the sensorimotor loop. In this proof-of-principle study, we explored an integrated approach for providing assistance as needed to amplify the task-related range of motion and the movement-related brain modulation during rehabilitation exercises of severely impaired patients. For this purpose, we combined these three approaches (BMI, NMES, and exoskeleton in an integrated neuroprosthesis and studied the feasibility of this device in seven severely affected chronic stroke patients who performed wrist flexion and extension exercises while receiving feedback via a virtual environment. They were assisted by a gravity-compensating, seven degree-of-freedom exoskeleton which was attached to the paretic arm. Neuromuscular electrical stimulation was applied to the wrist extensor and flexor muscles during the exercises and was controlled by a hybrid BMI based on both sensorimotor cortical desynchronization (ERD and electromyography (EMG activity. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e. induced no overt support. The hybrid BMI controlled the stimulation significantly better than the offline analyzed ERD (p=0.028 or EMG (p=0.021 modality alone. Neuromuscular stimulation could be well integrated into the exoskeleton-based training and amplified both the task-related range of motion (p=0.009 and the movement-related brain modulation (p=0

A theoretical framework for understanding neuromuscular response to lower extremity joint injury.

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Pietrosimone, Brian G; McLeod, Michelle M; Lepley, Adam S

2012-01-01

Neuromuscular alterations are common following lower extremity joint injury and often lead to decreased function and disability. These neuromuscular alterations manifest in inhibition or abnormal facilitation of the uninjured musculature surrounding an injured joint. Unfortunately, these neural alterations are poorly understood, which may affect clinical recognition and treatment of these injuries. Understanding how these neural alterations affect physical function may be important for proper clinical management of lower extremity joint injuries. Pertinent articles focusing on neuromuscular consequences and treatment of knee and ankle injuries were collected from peer-reviewed sources available on the Web of Science and Medline databases from 1975 through 2010. A theoretical model to illustrate potential relationships between neural alterations and clinical impairments was constructed from the current literature. Lower extremity joint injury affects upstream cortical and spinal reflexive excitability pathways as well as downstream muscle function and overall physical performance. Treatment targeting the central nervous system provides an alternate means of treating joint injury that may be effective for patients with neuromuscular alterations. Disability is common following joint injury. There is mounting evidence that alterations in the central nervous system may relate to clinical changes in biomechanics that may predispose patients to further injury, and novel clinical interventions that target neural alterations may improve therapeutic outcomes.

A robust neuromuscular system protects rat and human skeletal muscle from sarcopenia.

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Pannérec, Alice; Springer, Margherita; Migliavacca, Eugenia; Ireland, Alex; Piasecki, Mathew; Karaz, Sonia; Jacot, Guillaume; Métairon, Sylviane; Danenberg, Esther; Raymond, Frédéric; Descombes, Patrick; McPhee, Jamie S; Feige, Jerome N

2016-04-01

Declining muscle mass and function is one of the main drivers of loss of independence in the elderly. Sarcopenia is associated with numerous cellular and endocrine perturbations, and it remains challenging to identify those changes that play a causal role and could serve as targets for therapeutic intervention. In this study, we uncovered a remarkable differential susceptibility of certain muscles to age-related decline. Aging rats specifically lose muscle mass and function in the hindlimbs, but not in the forelimbs. By performing a comprehensive comparative analysis of these muscles, we demonstrate that regional susceptibility to sarcopenia is dependent on neuromuscular junction fragmentation, loss of motoneuron innervation, and reduced excitability. Remarkably, muscle loss in elderly humans also differs in vastus lateralis and tibialis anterior muscles in direct relation to neuromuscular dysfunction. By comparing gene expression in susceptible and non-susceptible muscles, we identified a specific transcriptomic signature of neuromuscular impairment. Importantly, differential molecular profiling of the associated peripheral nerves revealed fundamental changes in cholesterol biosynthetic pathways. Altogether our results provide compelling evidence that susceptibility to sarcopenia is tightly linked to neuromuscular decline in rats and humans, and identify dysregulation of sterol metabolism in the peripheral nervous system as an early event in this process.

["Habitual" left branch block alternating with 2 "disguised" bracnch block].

Science.gov (United States)

Lévy, S; Jullien, G; Mathieu, P; Mostefa, S; Gérard, R

1976-10-01

Two cases of alternating left bundle branch block and "masquerading block" (with left bundle branch morphology in the stnadard leads and right bundle branch block morphology in the precordial leads) were studied by serial tracings and his bundle electrocardiography. In case 1 "the masquerading" block was associated with a first degree AV block related to a prolongation of HV interval. This case is to our knowledge the first cas of alternating bundle branch block in which his bundle activity was recorded in man. In case 2, the patient had atrial fibrilation and His bundle recordings were performed while differents degrees of left bundle branch block were present: The mechanism of the alternation and the concept of "masquerading" block are discussed. It is suggested that this type of block represents a right bundle branch block associated with severe lesions of the "left system".

Changes in muscle strength in elderly women after proprioceptive neuromuscular facilitation based training

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Edivã Bernardo da Silva

Full Text Available Introduction Proprioceptive neuromuscular facilitation (PNF can be used to improve the quality of life of both healthy and diseased subjects, including the elderly, who suffer muscular weakness due to aging, leading to an impairment in functional capacity. Objective Verify the effectiveness of PNF as a tool for functional conditioning. Materials and methods We evaluated a total of ten elderly women aged 60–70 years, clinically healthy and physically active. They had the force of motion of hip flexion with knee extension analyzed by an analog dynamometer. They were then randomly and equally divided into experimental (EG and control group (CG. The GC was instructed to continue with their normal activities while the GE held 15 training sessions in the lower limb (LL based on the diagonal D1 and D2. Finally, a new collection wrench the two groups was performed and the data compared. Results There was a significant increase in the average strength of GE, on the order of 31% (p 0.05. Discussion : The results confirm that the FNP through initial work of readjustment and proprioceptive neuromuscular activation, and after that, conditioning of the muscle fibers (mainly resistive is capable of amplifying the force developed by the muscle. Conclusion The PNF was effective as training to gain muscle strength, should be better analyzed as a tool fitness, not to cause health risks, have low cost and easy application.

Neuromuscular Manifestations of West Nile Virus Infection

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A. Arturo eLeis

2012-03-01

Full Text Available The most common neuromuscular manifestation of West Nile virus (WNV infection is a poliomyelitis syndrome with asymmetric paralysis variably involving one (monoparesis to four limbs (quadriparesis, with or without brainstem involvement and respiratory failure. This syndrome of acute flaccid paralysis may occur without overt fever or meningoencephalitis. Although involvement of anterior horn cells in the spinal cord and motor neurons in the brainstem are the major sites of pathology responsible for neuromuscular signs, inflammation also may involve skeletal or cardiac muscle (myositis, myocarditis, motor axons (polyradiculitis, peripheral nerve (Guillain-Barré syndrome, brachial plexopathy. In addition, involvement of spinal sympathetic neurons and ganglia provides a plausible explanation for autonomic instability seen in some patients. Many patients also experience prolonged subjective generalized weakness and disabling fatigue. Despite recent evidence that WNV may persist long term in the central nervous system or periphery in animals, the evidence in humans is controversial. WNV persistence would be of great concern in immunosuppressed patients or in those with prolonged or recurrent symptoms. Support for the contention that WNV can lead to autoimmune disease arises from reports of patients presenting with various neuromuscular diseases that presumably involve autoimmune mechanisms (GBS, other demyelinating neu¬ropathies, myasthenia gravis, brachial plexopathies, stiff-person syndrome, and delayed or recurrent symptoms. Although there is no specific treatment or vaccine currently approved in humans, and the standard remains supportive care, drugs that can alter the cascade of immunobiochemical events leading to neuronal death may be potentially useful (high-dose corticosteroids, interferon preparations, and intravenous immune globulin containing WNV-specific antibodies. Human experience with these agents seems promising based on anecdotal

Acute neuromuscular weakness associated with dengue infection

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Harmanjit Singh Hira

2012-01-01

Full Text Available Background: Dengue infections may present with neurological complications. Whether these are due to neuromuscular disease or electrolyte imbalance is unclear. Materials and Methods: Eighty-eight patients of dengue fever required hospitalization during epidemic in year 2010. Twelve of them presented with acute neuromuscular weakness. We enrolled them for study. Diagnosis of dengue infection based on clinical profile of patients, positive serum IgM ELISA, NS1 antigen, and sero-typing. Complete hemogram, kidney and liver functions, serum electrolytes, and creatine phosphokinase (CPK were tested. In addition, two patients underwent nerve conduction velocity (NCV test and electromyography. Results: Twelve patients were included in the present study. Their age was between 18 and 34 years. Fever, myalgia, and motor weakness of limbs were most common presenting symptoms. Motor weakness developed on 2 nd to 4 th day of illness in 11 of 12 patients. In one patient, it developed on 10 th day of illness. Ten of 12 showed hypokalemia. One was of Guillain-Barré syndrome and other suffered from myositis; they underwent NCV and electromyography. Serum CPK and SGOT raised in 8 out of 12 patients. CPK of patient of myositis was 5098 IU. All of 12 patients had thrombocytopenia. WBC was in normal range. Dengue virus was isolated in three patients, and it was of serotype 1. CSF was normal in all. Within 24 hours, those with hypokalemia recovered by potassium correction. Conclusions: It was concluded that the dengue virus infection led to acute neuromuscular weakness because of hypokalemia, myositis, and Guillain-Barré syndrome. It was suggested to look for presence of hypokalemia in such patients.

Neuromuscular Responses to Simulated Brazilian Jiu-Jitsu Fights

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Corrêa da Silva Bruno Victor

2014-12-01

Full Text Available The aim of this study was to investigate the neuromuscular performance responses following successive Brazilian Jiu-Jitsu (BJJ fights. Twenty-three BJJ athletes (age: 26.3 ± 6.3 years; body mass: 79.4 ± 9.7 kg; body height: 1.80 ± 0.1 m undertook 3 simulated BJJ fights (10 min duration each separated by 15 min of rest. Neuromuscular performance was measured by the bench press throw (BPT and vertical counter movement jump (VCMJ tests, assessed before the 1st fight (Pre and after the last one (Post. Blood lactate (LA was measured at Pre, 1 min Post, and 15 min Post fights. Paired t-tests were employed in order to compare the BPT and VCMJ results. One-way ANOVA with Bonferroni post hoc tests were utilized to compare LA responses. The results revealed a significant (p < 0.05 increase in VCMJ performance (40.8 ± 5.5 cm Pre vs. 42.0 ± 5.8 cm Post, but no significant changes in the BPT (814 ± 167 W Pre vs. 835 ± 213 W Post were observed. LA concentration increased significantly (p < 0.05 at Post, both in the 1st min and the 15th min of recovery. We concluded that successive simulated BJJ fights demanded considerable anaerobic contribution of ATP supply, reinforcing the high-intensity intermittent nature of the sport. Nevertheless, no negative impact on acute neuromuscular performance (power was observed.

Neuromuscular rate of force development deficit in Parkinson disease.

Science.gov (United States)

Hammond, Kelley G; Pfeiffer, Ronald F; LeDoux, Mark S; Schilling, Brian K

2017-06-01

Bradykinesia and reduced neuromuscular force exist in Parkinson disease. The interpolated twitch technique has been used to evaluate central versus peripheral manifestations of neuromuscular strength in healthy, aging, and athletic populations, as well as moderate to advanced Parkinson disease, but this method has not been used in mild Parkinson disease. This study aimed to evaluate quadriceps femoris rate of force development and quantify potential central and peripheral activation deficits in individuals with Parkinson disease. Nine persons with mild Parkinson Disease (Hoehn & Yahr≤2, Unified Parkinson Disease Rating Scale total score=mean 19.1 (SD 5.0)) and eight age-matched controls were recruited in a cross-sectional investigation. Quadriceps femoris voluntary and stimulated maximal force and rate of force development were evaluated using the interpolated twitch technique. Thirteen participants satisfactorily completed the protocol. Individuals with early Parkinson disease (n=7) had significantly slower voluntary rate of force development (p=0.008; d=1.97) and rate of force development ratio (p=0.004; d=2.18) than controls (n=6). No significant differences were found between groups for all other variables. Persons with mild-to-moderate Parkinson disease display disparities in rate of force development, even without deficits in maximal force. The inability to produce force at a rate comparable to controls is likely a downstream effect of central dysfunction of the motor pathway in Parkinson disease. Copyright © 2017. Published by Elsevier Ltd.

Effect of salbutamol on neuromuscular function in endurance athletes.

Science.gov (United States)

Decorte, Nicolas; Bachasson, Damien; Guinot, Michel; Flore, Patrice; Levy, Patrick; Verges, Samuel; Wuyam, Bernard

2013-10-01

The potential ergogenic effects of therapeutic inhaled salbutamol doses in endurance athletes have been controversially discussed for decades. We hypothesized that salbutamol inhalation may increase peripheral muscle contractility, reduce fatigability, and improve force recovery after a localized exercise in endurance athletes. Eleven healthy, nonasthmatic male athletes with high aerobic capacities were recruited to be compared in a double-blinded, randomized crossover study of two dose levels of salbutamol (200 and 800 μg) and a placebo administered by inhalation before a quadriceps fatigue test. Subjects performed an incremental exercise protocol consisting in sets of 10 intermittent isometric contractions starting at 20% of maximum voluntary contraction (MVC) with 10% MVC increment until exhaustion. Femoral nerve magnetic stimulation was used during and after MVC to evaluate neuromuscular fatigue after each set, at task failure, and after 10 and 30 min of recovery. Initial MVC and evoked muscular responses were not modified with salbutamol (P > 0.05). The total number of submaximal contractions until task failure significantly differed between treatments (placebo, 72 ± 7; 200 µg, 78 ± 8; and 800 µg, 82 ± 7; P 0.05). Voluntary activation was unaffected by the fatiguing task and treatments (P > 0.05). Supratherapeutic inhaled doses of β2-agonists increased quadriceps endurance during an incremental and localized fatiguing task in healthy endurance-trained athletes without significant effect on neuromuscular fatigue. Further studies are needed to clarify the underlying mechanisms.

Influence of neuromuscular noise and walking speed on fall risk and dynamic stability in a 3D dynamic walking model.

Science.gov (United States)

Roos, Paulien E; Dingwell, Jonathan B

2013-06-21

Older adults and those with increased fall risk tend to walk slower. They may do this voluntarily to reduce their fall risk. However, both slower and faster walking speeds can predict increased risk of different types of falls. The mechanisms that contribute to fall risk across speeds are not well known. Faster walking requires greater forward propulsion, generated by larger muscle forces. However, greater muscle activation induces increased signal-dependent neuromuscular noise. These speed-related increases in neuromuscular noise may contribute to the increased fall risk observed at faster walking speeds. Using a 3D dynamic walking model, we systematically varied walking speed without and with physiologically-appropriate neuromuscular noise. We quantified how actual fall risk changed with gait speed, how neuromuscular noise affected speed-related changes in fall risk, and how well orbital and local dynamic stability measures predicted changes in fall risk across speeds. When we included physiologically-appropriate noise to the 'push-off' force in our model, fall risk increased with increasing walking speed. Changes in kinematic variability, orbital, and local dynamic stability did not predict these speed-related changes in fall risk. Thus, the increased neuromuscular variability that results from increased signal-dependent noise that is necessitated by the greater muscular force requirements of faster walking may contribute to the increased fall risk observed at faster walking speeds. The lower fall risk observed at slower speeds supports experimental evidence that slowing down can be an effective strategy to reduce fall risk. This may help explain the slower walking speeds observed in older adults and others. Copyright © 2013 Elsevier Ltd. All rights reserved.

One feature of the activated southern Ordos block: the Ziwuling small earthquake cluster

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Li Yuhang

2014-08-01

Full Text Available Small earthquakes (Ms > 2.0 have been recorded from 1970 to the present day and reveal a significant difference in seismicity between the stable Ordos block and its active surrounding area. The southern Ordos block is a conspicuous small earthquake belt clustered and isolated along the NNW direction and extends to the inner stable Ordos block; no active fault can match this small earthquake cluster. In this paper, we analyze the dynamic mechanism of this small earthquake cluster based on the GPS velocity field (from 1999 to 2007, which are mainly from Crustal Movement Observation Network of China (CMONOC with respect to the north and south China blocks. The principal direction of strain rate field, the expansion ratefield, the maximum shear strain rate, and the rotation rate were constrained using the GPS velocity field. The results show that the velocity field, which is bounded by the small earthquake cluster from Tongchuan to Weinan, differs from the strain rate field, and the crustal deformation is left-lateral shear. This left-lateral shear belt not only spatially coincides with the Neo-tectonic belt in the Weihe Basin but also with the NNW small earthquake cluster (the Ziwuling small earthquake cluster. Based on these studies, we speculate that the NNW small earthquake cluster is caused by left-lateral shear slip, which is prone to strain accumulation. When the strain releases along the weak zone of structure, small earthquakes diffuse within its upper crust. The maximum principal compression strees direction changed from NE-SW to NEE-SWW, and the former reverse faults in the southwestern margin of the Ordos block became a left-lateral strike slip due to readjustment of the tectonic strees field after the middle Pleistocene. The NNW Neo-tectonic belt in the Weihe Basin, the different movement character of the inner Weihe Basin (which was demonstrated through GPS measurements and the small earthquake cluster belt reflect the activated

[Neuromuscular disease: respiratory clinical assessment and follow-up].

Science.gov (United States)

Martínez Carrasco, C; Villa Asensi, J R; Luna Paredes, M C; Osona Rodríguez de Torres, F B; Peña Zarza, J A; Larramona Carrera, H; Costa Colomer, J

2014-10-01

Patients with neuromuscular disease are an important group at risk of frequently suffering acute or chronic respiratory failure, which is their main cause of death. They require follow-up by a pediatric respiratory medicine specialist from birth or diagnosis in order to confirm the diagnosis and treat any respiratory complications within a multidisciplinary context. The ventilatory support and the cough assistance have improved the quality of life and long-term survival for many of these patients. In this paper, the authors review the pathophysiology, respiratory function evaluation, sleep disorders, and the most frequent respiratory complications in neuromuscular diseases. The various treatments used, from a respiratory medicine point of view, will be analyzed in a next paper. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Different Muscle Action Training Protocols on Quadriceps-Hamstrings Neuromuscular Adaptations.

Science.gov (United States)

Ruas, Cassio V; Brown, Lee E; Lima, Camila D; Gregory Haff, G; Pinto, Ronei S

2018-05-01

The aim of this study was to compare three specific concentric and eccentric muscle action training protocols on quadriceps-hamstrings neuromuscular adaptations. Forty male volunteers performed 6 weeks of training (two sessions/week) of their dominant and non-dominant legs on an isokinetic dynamometer. They were randomly assigned to one of four groups; concentric quadriceps and concentric hamstrings (CON/CON, n=10), eccentric quadriceps and eccentric hamstrings (ECC/ECC, n=10), concentric quadriceps and eccentric hamstrings (CON/ECC, n=10), or no training (CTRL, n=10). Intensity of training was increased every week by decreasing the angular velocity for concentric and increasing it for eccentric groups in 30°/s increments. Volume of training was increased by adding one set every week. Dominant leg quadriceps and hamstrings muscle thickness, muscle quality, muscle activation, muscle coactivation, and electromechanical delay were tested before and after training. Results revealed that all training groups similarly increased MT of quadriceps and hamstrings compared to control (p0.05). These findings suggest that different short-term muscle action isokinetic training protocols elicit similar muscle size increases in hamstrings and quadriceps, but not for other neuromuscular variables. Nevertheless, effect sizes indicate that CON/ECC and ECC/ECC may elicit the greatest magnitude of change in muscle hypertrophy. © Georg Thieme Verlag KG Stuttgart · New York.

Genetics of Pediatric-Onset Motor Neuron and Neuromuscular Diseases

Science.gov (United States)

2015-08-24

Spinal Muscular Atrophy; Charcot-Marie-Tooth Disease; Muscular Dystrophy; Spinal Muscular Atrophy With Respiratory Distress 1; Amyotrophic Lateral Sclerosis; Motor Neuron Disease; Neuromuscular Disease; Peroneal Muscular Atrophy; Fragile X Syndrome

Propiocepción y control neuromuscular en el fútblo infantil

OpenAIRE

Zarza, Cristían

2014-01-01

En el fútbol profesional la escasa utilización de la pierna no hábil hace que muchas situaciones de juego no se resuelvan eficazmente, además de predisponer a la aparición de lesiones. El presente estudio se concentró en determinar la influencia del entrenamiento propioceptivo y del control neuromuscular en las cualidades físicas y técnicas del miembro no hábil. Objetivo: Indagar el nivel propioceptivo y de control neuromuscular del miembro inferior no hábil en chicos que re...

CT in neuromuscular disorders: A comparison of CT and histology

International Nuclear Information System (INIS)

Vliet, A.M. van der; Thijssen, H.O.M.; Merx, J.L.; Joosten, E.

1988-01-01

The value of CT-examination of the muscles compared to histology was studied in a retrospective analysis of 30 patients with clinical suspicion of neuromuscular disorder. In the evaluation of the CT-results descriptive criteria were used. The histologic diagnosis came from needle-biopsies taken from the quadriceps muscle. Considering the whole group of neuromuscular disorders, CT has an overall accuracy of 84.8%, a positive predictive value of 95.5% and a negative predictive value of 63.6%. This makes the use of CT as a diagnostic tool in neuromuscular disorders a reliable examination technique. In patients with a polymyositis there is even a 100% correlation between CT findings and biopsy results. Discrepancy between the biopsy results is remarkable of the quadriceps muscle and the CT findings: The number of abnormal histological findings is twice the number of abnormal CT findings. Using the more proximal gluteal region as a biopsy site would have decreased this discrepancy and would therefore have given a better correlation between CT and histology. The choice of protocol in determining the levels to be scanned is of great importance in achieving good reproducability in follow-up CT examinations. (orig.)

Magnetic resonance imaging (MRI) in the diagnosis of neuromuscular diseases

International Nuclear Information System (INIS)

Schalke, B.C.G.; Rohkamm, R.; Kaiser, W.

1990-01-01

In the last few years imaging procedures became also important in the diagnosis of neuromuscular diseases. We examined more than 150 patients with different neuromuscular diseases with MRI. Conventional diagnostic procedures like EMG, muscle biopsy can not be replaced by imaging procedures. MRI gives the chance to get additional diagnostic informations. It is possible to determine exact distribution and intensity of pathological changes in the muscle. Inflammatory muscle diseases can be differrentiated by T1/T2 values from atrophic/dystrophic diseases. The resolving power is very high and allows the exact detection of affected areas even in a single muscle. This can help to reduce false negative muscle biopsies. This is very useful in children and young adults. MRI can be used for the early detection of genetic myopathies and neuropathies. MRI allows to examine all muscles, including the heart, bone artefacts are absent. Heart muscle involvement in neuromuscular diseases can directly be shown by this method without any risk for the patient. In addition P-spectroscopy can be done for better understanding of pathogenesis, especially if the exact distribution of pathological changes is known. (author)

Neuromuscular deficits after peripheral joint injury: a neurophysiological hypothesis.

Science.gov (United States)

Ward, Sarah; Pearce, Alan J; Pietrosimone, Brian; Bennell, Kim; Clark, Ross; Bryant, Adam L

2015-03-01

In addition to biomechanical disturbances, peripheral joint injuries (PJIs) can also result in chronic neuromuscular alterations due in part to loss of mechanoreceptor-mediated afferent feedback. An emerging perspective is that PJI should be viewed as a neurophysiological dysfunction, not simply a local injury. Neurophysiological and neuroimaging studies have provided some evidence for central nervous system (CNS) reorganization at both the cortical and spinal levels after PJI. The novel hypothesis proposed is that CNS reorganization is the underlying mechanism for persisting neuromuscular deficits after injury, particularly muscle weakness. There is a lack of direct evidence to support this hypothesis, but future studies utilizing force-matching tasks with superimposed transcranial magnetic stimulation may be help clarify this notion. © 2014 Wiley Periodicals, Inc.

Theory of multichannel magnetic stimulation: toward functional neuromuscular rehabilitation.

Science.gov (United States)

Ruohonen, J; Ravazzani, P; Grandori, F; Ilmoniemi, R J

1999-06-01

Human excitable cells can be stimulated noninvasively with externally applied time-varying electromagnetic fields. The stimulation can be achieved either by directly driving current into the tissue (electrical stimulation) or by means of electro-magnetic induction (magnetic stimulation). While the electrical stimulation of the peripheral neuromuscular system has many beneficial applications, peripheral magnetic stimulation has so far only a few. This paper analyzes theoretically the use of multiple magnetic stimulation coils to better control the excitation and also to eventually mimic electrical stimulation. Multiple coils allow electronic spatial adjustment of the shape and location of the stimulus without moving the coils. The new properties may enable unforeseen uses for peripheral magnetic stimulation, e.g., in rehabilitation of patients with neuromuscular impairment.

Developmental and adult-specific processes contribute to de novo neuromuscular regeneration in the lizard tail.

Science.gov (United States)

Tokuyama, Minami A; Xu, Cindy; Fisher, Rebecca E; Wilson-Rawls, Jeanne; Kusumi, Kenro; Newbern, Jason M

2018-01-15

Peripheral nerves exhibit robust regenerative capabilities in response to selective injury among amniotes, but the regeneration of entire muscle groups following volumetric muscle loss is limited in birds and mammals. In contrast, lizards possess the remarkable ability to regenerate extensive de novo muscle after tail loss. However, the mechanisms underlying reformation of the entire neuromuscular system in the regenerating lizard tail are not completely understood. We have tested whether the regeneration of the peripheral nerve and neuromuscular junctions (NMJs) recapitulate processes observed during normal neuromuscular development in the green anole, Anolis carolinensis. Our data confirm robust axonal outgrowth during early stages of tail regeneration and subsequent NMJ formation within weeks of autotomy. Interestingly, NMJs are overproduced as evidenced by a persistent increase in NMJ density 120 and 250 days post autotomy (DPA). Substantial Myelin Basic Protein (MBP) expression could also be detected along regenerating nerves indicating that the ability of Schwann cells to myelinate newly formed axons remained intact. Overall, our data suggest that the mechanism of de novo nerve and NMJ reformation parallel, in part, those observed during neuromuscular development. However, the prolonged increase in NMJ number and aberrant muscle differentiation hint at processes specific to the adult response. An examination of the coordinated exchange between peripheral nerves, Schwann cells, and newly synthesized muscle of the regenerating neuromuscular system may assist in the identification of candidate molecules that promote neuromuscular recovery in organisms incapable of a robust regenerative response. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of exercise therapy on neuromuscular activity and knee strength in female adolescents with patellofemoral pain

DEFF Research Database (Denmark)

Rathleff, Michael S.; Samani, Afshin; Olesen, Jens L.

2016-01-01

. A random subsample of 57 female adolescents was included and tested at baseline and after 3months. Neuromuscular control of the knee was quantified as the complexity of surface electromyography of the vastus lateralis and vastus medialis during stair descent. Secondary outcomes were complexity of knee...... during stair descent than those receiving patient education alone. This suggest that exercise therapy has an effect not only on self-reported outcome measures but also on objective measures of thigh muscle function in female adolescents with patellofemoral pain....

Alterations in aerobic energy expenditure and neuromuscular function during a simulated cross-country skiathlon with the skating technique.

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Fabre, Nicolas; Mourot, Laurent; Zoppirolli, Chiara; Andersson, Erik; Willis, Sarah J; Holmberg, Hans-Christer

2015-04-01

Here, we tested the hypothesis that aerobic energy expenditure (AEE) is higher during a simulated 6-km (2 loops of 3-km each) "skiathlon" than during skating only on a treadmill and attempted to link any such increase to biomechanical and neuromuscular responses. Six elite male cross-country skiers performed two pre-testing time-trials (TT) to determine their best performances and to choose an appropriate submaximal speed for collection of physiological, biomechanical and neuromuscular data during two experimental sessions (exp). Each skier used, in randomized order, either the classical (CL) or skating technique (SK) for the first 3-km loop, followed by transition to the skating technique for the second 3-km loop. Respiratory parameters were recorded continuously. The EMG activity of the triceps brachii (TBr) and vastus lateralis (VLa) muscles during isometric contractions performed when the skiers were stationary (i.e., just before the first loop, during the transition, and after the second loop); their corresponding activity during dynamic contractions; and pole and plantar forces during the second loop were recorded. During the second 3-km of the TT, skating speed was significantly higher for the SK-SK than CL-SK. During this second loop, AEE was also higher (+1.5%) for CL-SKexp than SK-SKexp, in association with higher VLa EMG activity during both isometric and dynamic contractions, despite no differences in plantar or pole forces, poling times or cycle rates. Although the underlying mechanism remains unclear, during a skiathlon, the transition between the sections of classical skiing and skating alters skating performance (i.e., skiing speed), AEE and neuromuscular function. Copyright © 2015 Elsevier B.V. All rights reserved.

Alterations in neuromuscular function in girls with generalized joint hypermobility.

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Jensen, Bente Rona; Sandfeld, Jesper; Melcher, Pia Sandfeld; Johansen, Katrine Lyders; Hendriksen, Peter; Juul-Kristensen, Birgit

2016-10-03

Generalized Joint Hypermobility (GJH) is associated with increased risk of musculoskeletal joint pain. We investigated neuromuscular performance and muscle activation strategy. Girls with GJH and non-GJH (NGJH) performed isometric knee flexions (90°,110°,130°), and extensions (90°) at 20 % Maximum Voluntary Contraction, and explosive isometric knee flexions while sitting. EMG was recorded from knee flexor and extensor muscles. Early rate of torque development was 53 % faster for GJH. Reduced hamstring muscle activation in girls with GJH was found while knee extensor and calf muscle activation did not differ between groups. Flexion-extension and medial-lateral co-activation ratio during flexions were higher for girls with GJH than NGJH girls. Girls with GJH had higher capacity to rapidly generate force than NGJH girls which may reflect motor adaptation to compensate for hypermobility. Higher medial muscle activation indicated higher levels of medial knee joint compression in girls with GJH. Increased flexion-extension co-activation ratios in GJH were explained by decreased agonist drive to the hamstrings.

Neuromuscular Fatigue During 200 M Breaststroke

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Ana Conceição

2014-03-01

Full Text Available The aims of this study were: i to analyze activation patterns of four upper limb muscles (duration of the active and non-active phase in each lap of 200m breaststroke, ii quantify neuromuscular fatigue, with kinematics and physiologic assessment. Surface electromyogram was collected for the biceps brachii, deltoid anterior, pectoralis major and triceps brachii of nine male swimmers performing a maximal 200m breaststroke trial. Swimming speed, SL, SR, SI decreased from the 1st to the 3rd lap. SR increased on the 4th lap (35.91 ± 2.99 stroke·min-1. Peak blood lactate was 13.02 ± 1.72 mmol·l-1 three minutes after the maximal trial. The EMG average rectified value (ARV increased at the end of the race for all selected muscles, but the deltoid anterior and pectoralis major in the 1st lap and for biceps brachii, deltoid anterior and triceps brachii in the 4th lap. The mean frequency of the power spectral density (MNF decreased at the 4th lap for all muscles. These findings suggest the occurrence of fatigue at the beginning of the 2nd lap in the 200m breaststroke trial, characterized by changes in kinematic parameters and selective changes in upper limb muscle action. There was a trend towards a non-linear fatigue state.

Altered knee joint neuromuscular control during landing from a jump in 10-15 year old children with Generalised Joint Hypermobility. A substudy of the CHAMPS-study Denmark.

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Junge, Tina; Wedderkopp, Niels; Thorlund, Jonas Bloch; Søgaard, Karen; Juul-Kristensen, Birgit

2015-06-01

Generalised Joint Hypermobility (GJH) is considered an intrinsic risk factor for knee injuries. Knee neuromuscular control during landing may be altered in GJH due to reduced passive stability. The aim was to identify differences in knee neuromuscular control during landing of the Single-Leg-Hop-for-Distance test (SLHD) in 25 children with GJH compared to 29 children without GJH (controls), all 10-15years. Inclusion criteria for GJH: Beighton score⩾5/9 and minimum one hypermobile knee. EMG was recorded from the quadriceps, the hamstring and the calf muscles, presented relative to Maximum Voluntary Electrical activity (MVE). There was no difference in jump length between groups. Before landing, GJH had 33% lower Semitendinosus, but 32% higher Gastrocnemius Medialis activity and 39% higher co contraction of the lateral knee muscles, than controls. After landing, GJH had 36% lower Semitendinosus activity than controls, all significant findings. Although the groups performed equally in SLHD, GJH had a Gastrocnemius Medialis dominated neuromuscular strategy before landing, plausibly caused by reduced Semitendinosus activity. Reduced Semitendinosus activity was seen in GJH after landing, but with no compensatory Gastrocnemius Medialis activity. Reduced pre and post-activation of the Semitendinosus may present a risk factor for traumatic knee injuries as ACL ruptures in GJH with knee hypermobility. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Assessment of bone density in patients with scoliosis neuromuscular secondary to cerebral palsy

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Charbel Jacob Júnior

2014-09-01

Full Text Available OBJECTIVE: To evaluate bone mineral density in patients with neuromuscular scoliosis secondary to spastic quadriplegic cerebral palsy. METHODS: A prospective descriptive study in which, in addition to bone densitometry, the anthropometric data of the patients were assessed. As inclusion criterion we adopted patients with spastic quadriplegic cerebral palsy, wheelchair users, aged between 10 and 20 years and with neuromuscular scoliosis. RESULTS: We evaluated 31 patients, 20 female, whose average age was 14.2 years. The mean bone density was -3.2 standard deviation (Z-score, with mean biceps circumference of 19.4 cm, calf circumference 18.6 cm and BMI of 13.6 kg/m². CONCLUSION: There is a high incidence of osteoporosis in patients with neuromuscular scoliosis secondary to spastic quadriplegic cerebral palsy.

Injection of a soluble fragment of neural agrin (NT-1654 considerably improves the muscle pathology caused by the disassembly of the neuromuscular junction.

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Stefan Hettwer

Full Text Available Treatment of neuromuscular diseases is still an unsolved problem. Evidence over the last years strongly indicates the involvement of malformation and dysfunction of neuromuscular junctions in the development of such medical conditions. Stabilization of NMJs thus seems to be a promising approach to attenuate the disease progression of muscle wasting diseases. An important pathway for the formation and maintenance of NMJs is the agrin/Lrp4/MuSK pathway. Here we demonstrate that the agrin biologic NT-1654 is capable of activating the agrin/Lrp4/MuSK system in vivo, leading to an almost full reversal of the sarcopenia-like phenotype in neurotrypsin-overexpressing (SARCO mice. We also show that injection of NT-1654 accelerates muscle re-innervation after nerve crush. This report demonstrates that a systemically administered agrin fragment has the potential to counteract the symptoms of neuromuscular disorders.

Schwann Cells in Neuromuscular Junction Formation and Maintenance.

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Barik, Arnab; Li, Lei; Sathyamurthy, Anupama; Xiong, Wen-Cheng; Mei, Lin

2016-09-21

The neuromuscular junction (NMJ) is a tripartite synapse that is formed by motor nerve terminals, postjunctional muscle membranes, and terminal Schwann cells (TSCs) that cover the nerve-muscle contact. NMJ formation requires intimate communications among the three different components. Unlike nerve-muscle interaction, which has been well characterized, less is known about the role of SCs in NMJ formation and maintenance. We show that SCs in mice lead nerve terminals to prepatterned AChRs. Ablating SCs at E8.5 (i.e., prior nerve arrival at the clusters) had little effect on aneural AChR clusters at E13.5, suggesting that SCs may not be necessary for aneural clusters. SC ablation at E12.5, a time when phrenic nerves approach muscle fibers, resulted in smaller and fewer nerve-induced AChR clusters; however, SC ablation at E15.5 reduced AChR cluster size but had no effect on cluster density, suggesting that SCs are involved in AChR cluster maturation. Miniature endplate potential amplitude, but not frequency, was reduced when SCs were ablated at E15.5, suggesting that postsynaptic alterations may occur ahead of presynaptic deficits. Finally, ablation of SCs at P30, after NMJ maturation, led to NMJ fragmentation and neuromuscular transmission deficits. Miniature endplate potential amplitude was reduced 3 d after SC ablation, but both amplitude and frequency were reduced 6 d after. Together, these results indicate that SCs are not only required for NMJ formation, but also necessary for its maintenance; and postsynaptic function and structure appeared to be more sensitive to SC ablation. Neuromuscular junctions (NMJs) are critical for survival and daily functioning. Defects in NMJ formation during development or maintenance in adulthood result in debilitating neuromuscular disorders. The role of Schwann cells (SCs) in NMJ formation and maintenance was not well understood. We genetically ablated SCs during development and after NMJ formation to investigate the consequences

Gradual nerve elongation affects nerve cell bodies and neuro-muscular junctions.

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Kazuo Ikeda, K I; Masaki Matsuda, M M; Daisuke Yamauchi, D Y; Katsuro Tomita, K T; Shigenori Tanaka, S T

2005-07-01

The purpose of this study is to clarify the reactions of the neuro-muscular junction and nerve cell body to gradual nerve elongation. The sciatic nerves of Japanese white rabbits were lengthened by 30 mm in increments of 0.8 mm/day, 2.0 mm/day and 4.0 mm/day. A scanning electron microscopic examination showed no degenerative change at the neuro-muscular junction, even eight weeks after elongation in the 4-mm group. Hence, neuro-muscular junction is not critical for predicting damage from gradual nerve elongation. There were no axon reaction cells in the 0.8-mm group, a small amount in the 2-mm group, and a large amount in the 4-mm group. The rate of growth associated protein-43 positive nerve cells was significant in the 4-mm group. Hence, the safe speed for nerve cells appeared to be 0.8-mm/day, critical speed to be 2.0-mm/day, and dangerous speed to be 4.0-mm/day in this elongation model.

Spinal Muscular Atrophy: From Defective Chaperoning of snRNP Assembly to Neuromuscular Dysfunction

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Maia Lanfranco

2017-06-01

Full Text Available Spinal Muscular Atrophy (SMA is a neuromuscular disorder that results from decreased levels of the survival motor neuron (SMN protein. SMN is part of a multiprotein complex that also includes Gemins 2–8 and Unrip. The SMN-Gemins complex cooperates with the protein arginine methyltransferase 5 (PRMT5 complex, whose constituents include WD45, PRMT5 and pICln. Both complexes function as molecular chaperones, interacting with and assisting in the assembly of an Sm protein core onto small nuclear RNAs (snRNAs to generate small nuclear ribonucleoproteins (snRNPs, which are the operating components of the spliceosome. Molecular and structural studies have refined our knowledge of the key events taking place within the crowded environment of cells and the numerous precautions undertaken to ensure the faithful assembly of snRNPs. Nonetheless, it remains unclear whether a loss of chaperoning in snRNP assembly, considered as a “housekeeping” activity, is responsible for the selective neuromuscular phenotype in SMA. This review thus shines light on in vivo studies that point toward disturbances in snRNP assembly and the consequential transcriptome abnormalities as the primary drivers of the progressive neuromuscular degeneration underpinning the disease. Disruption of U1 snRNP or snRNP assembly factors other than SMN induces phenotypes that mirror aspects of SMN deficiency, and splicing defects, described in numerous SMA models, can lead to a DNA damage and stress response that compromises the survival of the motor system. Restoring the correct chaperoning of snRNP assembly is therefore predicted to enhance the benefit of SMA therapeutic modalities based on augmenting SMN expression.

Acute fatigue impairs neuromuscular activity of anterior cruciate ligament-agonist muscles in female team handball players

DEFF Research Database (Denmark)

Zebis, M K; Bencke, J; Andersen, L L

2011-01-01

In sports, like team handball, fatigue has been associated with an increased risk of anterior cruciate ligament (ACL) injury. While effects of fatigue on muscle function are commonly assessed during maximal isometric voluntary contraction (MVC), such measurements may not relate to the muscle...... function during match play. The purpose of this study was to investigate the effect of muscle fatigue induced by a simulated handball match on neuromuscular strategy during a functional sidecutting movement, associated with the incidence of ACL injury. Fourteen female team handball players were tested...

Creating Active Device Materials for Nanoelectronics Using Block Copolymer Lithography.

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Cummins, Cian; Bell, Alan P; Morris, Michael A

2017-09-30

The prolonged and aggressive nature of scaling to augment the performance of silicon integrated circuits (ICs) and the technical challenges and costs associated with this has led to the study of alternative materials that can use processing schemes analogous to semiconductor manufacturing. We examine the status of recent efforts to develop active device elements using nontraditional lithography in this article, with a specific focus on block copolymer (BCP) feature patterning. An elegant route is demonstrated using directed self-assembly (DSA) of BCPs for the fabrication of aligned tungsten trioxide (WO₃) nanowires towards nanoelectronic device application. The strategy described avoids conventional lithography practices such as optical patterning as well as repeated etching and deposition protocols and opens up a new approach for device development. Nanoimprint lithography (NIL) silsesquioxane (SSQ)-based trenches were utilized in order to align a cylinder forming poly(styrene)- block -poly(4-vinylpyridine) (PS- b -P4VP) BCP soft template. We outline WO₃ nanowire fabrication using a spin-on process and the symmetric current-voltage characteristics of the resulting Ti/Au (5 nm/45 nm) contacted WO₃ nanowires. The results highlight the simplicity of a solution-based approach that allows creating active device elements and controlling the chemistry of specific self-assembling building blocks. The process enables one to dictate nanoscale chemistry with an unprecedented level of sophistication, forging the way for next-generation nanoelectronic devices. We lastly outline views and future research studies towards improving the current platform to achieve the desired device performance.

Creating Active Device Materials for Nanoelectronics Using Block Copolymer Lithography

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Cian Cummins

2017-09-01

Full Text Available The prolonged and aggressive nature of scaling to augment the performance of silicon integrated circuits (ICs and the technical challenges and costs associated with this has led to the study of alternative materials that can use processing schemes analogous to semiconductor manufacturing. We examine the status of recent efforts to develop active device elements using nontraditional lithography in this article, with a specific focus on block copolymer (BCP feature patterning. An elegant route is demonstrated using directed self-assembly (DSA of BCPs for the fabrication of aligned tungsten trioxide (WO3 nanowires towards nanoelectronic device application. The strategy described avoids conventional lithography practices such as optical patterning as well as repeated etching and deposition protocols and opens up a new approach for device development. Nanoimprint lithography (NIL silsesquioxane (SSQ-based trenches were utilized in order to align a cylinder forming poly(styrene-block-poly(4-vinylpyridine (PS-b-P4VP BCP soft template. We outline WO3 nanowire fabrication using a spin-on process and the symmetric current-voltage characteristics of the resulting Ti/Au (5 nm/45 nm contacted WO3 nanowires. The results highlight the simplicity of a solution-based approach that allows creating active device elements and controlling the chemistry of specific self-assembling building blocks. The process enables one to dictate nanoscale chemistry with an unprecedented level of sophistication, forging the way for next-generation nanoelectronic devices. We lastly outline views and future research studies towards improving the current platform to achieve the desired device performance.

Anormalidades neuromuscular no desuso, senilidade e caquexia Neuromuscular abnormalities in disuse, cachexia and ageing

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João Aris Kouyoumdjian

1993-09-01

Full Text Available É feita revisão de literatura sobre as principais alterações do sistema neuromuscular no desuso, senilidade e caquexia no ser humano e em modelos animais. A diminuição do diâmetro das fibras musculares após período de inatividade/imobilidade (desuso deve-se à perda de miofibrilas periféricas não ocorrendo formação de core-targetóides ou diminuição da atividade da miofosforilase, próprias da desnervação; mantêm-se a liberação espontânea de acetilcolina e fatores tróficos na junção mio-neural; em geral são afetadas preferencialmente fibras II, que podem assumir forma angular. Existe um processo contínuo intrínseco de envelhecimento de nervos e músculos, com desnervação e reinervação lenta e progressiva; o número de unidades motoras se reduz após 60 anos, sem ocorrência de atividade elétrica desnervatória; a quantidade de acetilcolina liberada nos neurônios terminais e a capacidade máxima de utilização de oxigênio estão diminuídas; a redução da capacidade oxidativa mitocondrial pode explicar o aumento de fibras I, mantendo-se o equilíbrio energético. Após poucas semanas de caquexia as fibras musculares podem ter o diâmetro reduzido em 30%, essa redução ocorre em ordem decrescente nos músculos dos membros inferiores, superiores e tronco; existe atrofia II preferencial com fibras angulares ocasionais, redução de RNA/síntese proteica, mantendo-se DNA normal.Cachexia, ageing and disuse and their effects on the human and animals neuromuscular system are reviewed. Disuse induces reduction of muscle fibers (mainly II diameter with peripheral myofibrils lost; there is no core-targetoid or even reduction on myophosphorilase activity, both typical of denervation; the acetylcholine spontaneous release and trophic factors on myoneural junction are maintained; muscle fibers could change to angular shape. Ageing affects nerve and muscle by a continuous and progressive process of denervation and reinner

Effect of knee angle on neuromuscular assessment of plantar flexor muscles: A reliability study

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Cornu, Christophe; Jubeau, Marc

2018-01-01

Introduction This study aimed to determine the intra- and inter-session reliability of neuromuscular assessment of plantar flexor (PF) muscles at three knee angles. Methods Twelve young adults were tested for three knee angles (90°, 30° and 0°) and at three time points separated by 1 hour (intra-session) and 7 days (inter-session). Electrical (H reflex, M wave) and mechanical (evoked and maximal voluntary torque, activation level) parameters were measured on the PF muscles. Intraclass correlation coefficients (ICC) and coefficients of variation were calculated to determine intra- and inter-session reliability. Results The mechanical measurements presented excellent (ICC>0.75) intra- and inter-session reliabilities regardless of the knee angle considered. The reliability of electrical measurements was better for the 90° knee angle compared to the 0° and 30° angles. Conclusions Changes in the knee angle may influence the reliability of neuromuscular assessments, which indicates the importance of considering the knee angle to collect consistent outcomes on the PF muscles. PMID:29596480

Dysfunction of the neuromuscular junction in spinal muscular atrophy types 2 and 3.

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Wadman, Renske I; Vrancken, Alexander F J E; van den Berg, Leonard H; van der Pol, W Ludo

2012-11-13

Spinal muscular atrophy (SMA) is pathologically characterized by degeneration of anterior horn cells. Recent observations in animal models of SMA and muscle tissue from patients with SMA suggest additional abnormalities in the development and maturation of the neuromuscular junction. We therefore evaluated neuromuscular junction function in SMA with repetitive nerve stimulation. In this case-control study, repetitive nerve stimulation was performed in 35 patients with SMA types 2, 3, and 4, 20 healthy controls, and 5 controls with motor neuron disease. Pathologic decremental responses (>10%) during 3-Hz repetitive nerve stimulation were observed in 17 of 35 patients (49%) with SMA types 2 and 3, but not in healthy controls or controls with motor neuron disease. None of the patients or controls had an abnormal incremental response of >60%. The presence of an abnormal decremental response was not specific for the type of SMA, nor was it associated with compound muscle action potential amplitude, clinical scores, or disease duration. Two of 4 patients with SMA type 3 who tried pyridostigmine reported increased stamina. These data suggest dysfunction of the neuromuscular junction in patients with SMA types 2 and 3. Therefore, drugs that facilitate neuromuscular transmission are candidate drugs for evaluation in carefully designed, placebo-controlled, clinical trials.

Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs.

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Bühler, Mira; Vollstädt-Klein, Sabine; Klemen, Jane; Smolka, Michael N

2008-07-22

Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA) 19, 37, 48), parietal areas (BA 7, 40) and areas in the frontal lobe (BA 6, 44). Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli.Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal.

Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs

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Klemen Jane

2008-07-01

Full Text Available Abstract Background Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. Methods To clarify how experimental functional magnetic resonance imaging (fMRI design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. Results Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA 19, 37, 48, parietal areas (BA 7, 40 and areas in the frontal lobe (BA 6, 44. Conclusion Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli. Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal.

MRI in neuromuscular disorders

International Nuclear Information System (INIS)

Fischmann, Arne

2014-01-01

Neuromuscular disorders are caused by damage of the skeletal muscles or supplying nerves, in many cases due to a genetic defect, resulting in progressive disability, loss of ambulation and often a reduced life expectancy. Previously only supportive care and steroids were available as treatments, but several novel therapies are under development or in clinical trial phase. Muscle imaging can detect specific patterns of involvement and facilitate diagnosis and guide genetic testing. Quantitative MRT can be used to monitor disease progression either to monitor treatment or as a surrogate parameter for clinical trails. Novel imaging sequences can provide insights into disease pathology and muscle metabolism. (orig.)

Diagnostic value of CT scanning in neuromuscular diseases

International Nuclear Information System (INIS)

Bulcke, J.A.L.; Leuven Univ.; Herpels, V.

1983-01-01

The diagnosis of myopathies has become easier since the CT technique is available. In this article the possibilities of CT for diagnostic procedures of neuromuscular diseases are pointed out. Density measurements increase differentiation of atrophy or hypertrophy of muscles as well as other pathological changes. (orig.)

Comparison of the Effect of Neuromuscular Electrical Stimulation ...

African Journals Online (AJOL)

Children with cerebral palsy (CP) often demonstrate poor hand function due to spasticity. Thus spasticity in the wrist and finger flexors poses a great deal of functional limitations. This study was therefore designed to compare the effectiveness of Cryotherapy and Neuromuscular Electrical Stimulation (NMES) on spasticity ...

Block That Pain!

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Skip Navigation Bar Home Current Issue Past Issues Block That Pain! Past Issues / Fall 2007 Table of ... contrast, most pain relievers used for surgical procedures block activity in all types of neurons. This can ...

An improved method to determine neuromuscular properties using force laws - From single muscle to applications in human movements.

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Siebert, T; Sust, M; Thaller, S; Tilp, M; Wagner, H

2007-04-01

We evaluate an improved method for individually determining neuromuscular properties in vivo. The method is based on Hill's equation used as a force law combined with Newton's equation of motion. To ensure the range of validity of Hill's equation, we first perform detailed investigations on in vitro single muscles. The force-velocity relation determined with the model coincides well with results obtained by standard methods (r=.99) above 20% of the isometric force. In addition, the model-predicted force curves during work loop contractions very well agree with measurements (mean difference: 2-3%). Subsequently, we deduce theoretically under which conditions it is possible to combine several muscles of the human body to model muscles. This leads to a model equation for human leg extension movements containing parameters for the muscle properties and for the activation. To numerically determine these invariant neuromuscular properties we devise an experimental method based on concentric and isometric leg extensions. With this method we determine individual muscle parameters from experiments such that the simulated curves agree well with experiments (r=.99). A reliability test with 12 participants revealed correlations r=.72-.91 for the neuromuscular parameters (p<.01). Predictions of similar movements under different conditions show mean errors of about 5%. In addition, we present applications in sports practise and theory.

Onset and duration of action of rocuronium - from tracheal intubation, through intense block to complete recovery

DEFF Research Database (Denmark)

Schultz, P.; Ibsen, M.; Østergaard, Doris

2001-01-01

pharmacodynamic, neuromuscular relaxant, rocuronium, neuromuscular transmission, nerve stimulator, post tetanic count......pharmacodynamic, neuromuscular relaxant, rocuronium, neuromuscular transmission, nerve stimulator, post tetanic count...

Cross‐disease comparison of amyotrophic lateral sclerosis and spinal muscular atrophy reveals conservation of selective vulnerability but differential neuromuscular junction pathology

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Nijssen, Jik; Frost‐Nylen, Johanna

2015-01-01

Neuromuscular junctions are primary pathological targets in the lethal motor neuron diseases spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Synaptic pathology and denervation of target muscle fibers has been reported prior to the appearance of clinical symptoms in mouse models of both diseases, suggesting that neuromuscular junctions are highly vulnerable from the very early stages, and are a key target for therapeutic intervention. Here we examined neuromuscular pathology longitudinally in three clinically relevant muscle groups in mouse models of ALS and SMA in order to assess their relative vulnerabilities. We show for the first time that neuromuscular junctions of the extraocular muscles (responsible for the control of eye movement) were resistant to degeneration in endstage SMA mice, as well as in late symptomatic ALS mice. Tongue muscle neuromuscular junctions were also spared in both animal models. Conversely, neuromuscular junctions of the lumbrical muscles of the hind‐paw were vulnerable in both SMA and ALS, with a loss of neuronal innervation and shrinkage of motor endplates in both diseases. Thus, the pattern of selective vulnerability was conserved across these two models of motor neuron disease. However, the first evidence of neuromuscular pathology occurred at different timepoints of disease progression, with much earlier evidence of presynaptic involvement in ALS, progressing to changes on the postsynaptic side. Conversely, in SMA changes appeared concomitantly at the neuromuscular junction, suggesting that mechanisms of neuromuscular disruption are distinct in these diseases. J. Comp. Neurol. 524:1424–1442, 2016. © 2015 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:26502195

Professional Soccer Player Neuromuscular Responses and Perceptions to Acute Whole Body Vibration Differ from Amateur Counterparts

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Ross Cloak, Andrew Lane, Matthew Wyon

2016-03-01

Full Text Available Acute whole body vibration (WBV is an increasingly popular training technique amongst athletes immediately prior to performance and during scheduled breaks in play. Despite its growing popularity, evidence to demonstrate its effectiveness on acute neuromuscular responses is unclear, and suggestions that athlete ability impacts effectiveness warrant further investigation. The purpose of this study was to compare the neuromuscular effects of acute WBV and perceptions of whether WBV is an effective intervention between amateur and professional soccer players. Participants were 44 male soccer players (22 professional and 22 amateur; age: 23.1 ± 3.7 years, body mass: 75.6 ± 8.8 kg and height: 1.77 ± 0.05 m. Participants in each group were randomly assigned to either an intervention of 3 x 60 s of WBV at 40 Hz (8mm peak-to-peak displacement or control group. Peak knee isometric force, muscle activation and post activation potentiation (PAP of the knee extensors along with self-report questionnaire of the perceived benefits of using the intervention were collected. A three-way ANOVA with repeated measures revealed professional players demonstrated a significant 10.6% increase (p < 0.01, Partial Eta2 = 0.22 in peak knee isometric force following acute WBV with no significant differences among amateur players. A significant difference (p < 0.01, Partial Eta2 = 0.16 in PAP amongst professional players following acute WBVT was also reported. No significant differences amongst amateur players were reported across measurements. Results also indicated professional players reported significantly stronger positive beliefs in the effectiveness of the WBV intervention (p < 0.01, Partial Eta2 = 0.27 compared to amateur players. Acute WBV elicited a positive neuromuscular response amongst professional players identified by PAP and improvements in knee isometric peak force as well as perceived benefits of the intervention, benefits not found among amateur players.

Speed adaptation in a powered transtibial prosthesis controlled with a neuromuscular model.

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Markowitz, Jared; Krishnaswamy, Pavitra; Eilenberg, Michael F; Endo, Ken; Barnhart, Chris; Herr, Hugh

2011-05-27

Control schemes for powered ankle-foot prostheses would benefit greatly from a means to make them inherently adaptive to different walking speeds. Towards this goal, one may attempt to emulate the intact human ankle, as it is capable of seamless adaptation. Human locomotion is governed by the interplay among legged dynamics, morphology and neural control including spinal reflexes. It has been suggested that reflexes contribute to the changes in ankle joint dynamics that correspond to walking at different speeds. Here, we use a data-driven muscle-tendon model that produces estimates of the activation, force, length and velocity of the major muscles spanning the ankle to derive local feedback loops that may be critical in the control of those muscles during walking. This purely reflexive approach ignores sources of non-reflexive neural drive and does not necessarily reflect the biological control scheme, yet can still closely reproduce the muscle dynamics estimated from biological data. The resulting neuromuscular model was applied to control a powered ankle-foot prosthesis and tested by an amputee walking at three speeds. The controller produced speed-adaptive behaviour; net ankle work increased with walking speed, highlighting the benefits of applying neuromuscular principles in the control of adaptive prosthetic limbs.

Management of neuromuscular diseases and spinal muscular atrophy in Latin America.

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Monges, S; Rosa, A L

2017-09-01

Latin America (LA) has a population of ~645 million people distributed over 33 countries with marked political, cultural and economic differences. In LA, patients with inherited neuromuscular diseases (NMDs) often do not have access to specialized medical centers and many of them go undiagnosed. General management and care of spinal muscular dystrophy (SMA) patients in the region varies due to heterogeneous health care. An active generation of young clinical neurologists is being trained for the specialized care of SMA and other neuromuscular (NM) patients, both in the private and public sectors. The Euro-Latin-American Summer School of Myology (EVELAM) as well as efforts of professionals at large public centers in the major cities of LA have a leading role in this development. Different regional academic-scientific organizations as well as the expanding number of telethon centers and the creation of parent organizations, mostly concerning SMA, all together are contributing to the increased quality of the management of NMD patients. Over the past years, academic and clinical research, as well as the establishment of qualified centers for the molecular testing of NMD are pushing forward the creation of patient registries and the development of specific clinical trials, with Argentina and Brazil having a major role in this field. Nevertheless, increased awareness and further training of specialized health professionals are necessary to reach patients that are currently lacking care throughout the region.

Sugammadex in patients with chronic renal failure: two case reports

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Gwi Eun Yeo

2016-04-01

Full Text Available Rocuronium is a non-depolarizing aminosteroidal neuromuscular blocking agent that is widely used in general anesthesia. Its effects may be prolonged in patients with renal disease, especially renal failure, due to reduced clearance of the drug. Sugammadex, a modified γ-cyclodextrin, is known to be a highly effective reversal agent for rocuronium-induced muscle relaxation. However, the administration of sugammadex for reversal of rocuronium-induced neuromuscular block in patients with renal disease is controversial. Recently, we administered rocuronium for neuromuscular blockade during the surgery of two patients with chronic renal failure, instead of cisatracurium, a benzylisoquinoline compound. Therefore, we had to administer sugammadex to ensure maximum alleviation of residual neuromuscular blockade risk after surgery. Although the effect of rocuronium was prolonged during surgery, sugammadex quickly and completely restored the response of train-of-four stimulation postoperatively. There were no residual neuromuscular block signs or symptoms observed in these patients throughout the postoperative period. In this report, we share our experience with these cases, and discuss the effectiveness and safety of sugammadex in the context of chronic renal failure.   Keywords: Neuromuscular blockade; Neuromuscular monitoring; Renal failure; Residual neuromuscular blockade; Rocuronium; Sugammadex

Early appearance and possible roles of non-neuromuscular cholinesterases.

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Carla eFalugi

2012-04-01

Full Text Available The biological function of the cholinesterase (ChE enzymes is well known and has been studied since the beginning of the XXth century; in particular, acetylcholinesterase (AChE, E.C. 3.1.1.7 is an enzyme playing a key role in the modulation of neuromuscular impulse transmission. However, in the past decades, there has been increasing interest concerning its role in regulating non-neuromuscular cell-to-cell interactions mediated by intracellular ion concentration changes, like the ones occurring during gamete interaction and embryonic development. An understanding of the mechanisms of the cholinergic regulation of these events can help us foresee the possible impact on environmental and human health, including gamete efficiency and possible teratogenic effects on different models, and help elucidate the extent to which exposure to ChE inhibitors may affect human health.

Minocycline blocks glial cell activation and ventilatory acclimatization to hypoxia.

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Stokes, Jennifer A; Arbogast, Tara E; Moya, Esteban A; Fu, Zhenxing; Powell, Frank L

2017-04-01

Ventilatory acclimatization to hypoxia (VAH) is the time-dependent increase in ventilation, which persists upon return to normoxia and involves plasticity in both central nervous system respiratory centers and peripheral chemoreceptors. We investigated the role of glial cells in VAH in male Sprague-Dawley rats using minocycline, an antibiotic that inhibits microglia activation and has anti-inflammatory properties, and barometric pressure plethysmography to measure ventilation. Rats received either minocycline (45mg/kg ip daily) or saline beginning 1 day before and during 7 days of chronic hypoxia (CH, Pi O 2  = 70 Torr). Minocycline had no effect on normoxic control rats or the hypercapnic ventilatory response in CH rats, but minocycline significantly ( P minocycline administration during only the last 3 days of CH did not reverse VAH. Microglia and astrocyte activation in the nucleus tractus solitarius was quantified from 30 min to 7 days of CH. Microglia showed an active morphology (shorter and fewer branches) after 1 h of hypoxia and returned to the control state (longer filaments and extensive branching) after 4 h of CH. Astrocytes increased glial fibrillary acidic protein antibody immunofluorescent intensity, indicating activation, at both 4 and 24 h of CH. Minocycline had no effect on glia in normoxia but significantly decreased microglia activation at 1 h of CH and astrocyte activation at 24 h of CH. These results support a role for glial cells, providing an early signal for the induction but not maintenance of neural plasticity underlying ventilatory acclimatization to hypoxia. NEW & NOTEWORTHY The signals for neural plasticity in medullary respiratory centers underlying ventilatory acclimatization to chronic hypoxia are unknown. We show that chronic hypoxia activates microglia and subsequently astrocytes. Minocycline, an antibiotic that blocks microglial activation and has anti-inflammatory properties, also blocks astrocyte activation in respiratory

A neuromuscular exercise programme versus standard care for patients with traumatic anterior shoulder instability

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Eshoj, Henrik; Rasmussen, Sten; Frich, Lars Henrik

2017-01-01

BACKGROUND: Anterior shoulder dislocation is a common injury and may have considerable impact on shoulder-related quality of life (QoL). If not warranted for initial stabilising surgery, patients are mostly left with little to no post-traumatic rehabilitation. This may be due to lack of evidence......-based exercise programmes. In similar, high-impact injuries (e.g. anterior cruciate ligament tears in the knee) neuromuscular exercise has shown large success in improving physical function and QoL. Thus, the objective of this trial is to compare a nonoperative neuromuscular exercise shoulder programme...... dislocations due to at least one traumatic event will be randomised to 12 weeks of either a standardised, individualised or physiotherapist-supervised neuromuscular shoulder exercise programme or standard care (self-managed shoulder exercise programme). Patients will be stratified according to injury status...

Accuracy of a Custom Physical Activity and Knee Angle Measurement Sensor System for Patients with Neuromuscular Disorders and Gait Abnormalities

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Frank Feldhege

2015-05-01

Full Text Available Long-term assessment of ambulatory behavior and joint motion are valuable tools for the evaluation of therapy effectiveness in patients with neuromuscular disorders and gait abnormalities. Even though there are several tools available to quantify ambulatory behavior in a home environment, reliable measurement of joint motion is still limited to laboratory tests. The aim of this study was to develop and evaluate a novel inertial sensor system for ambulatory behavior and joint motion measurement in the everyday environment. An algorithm for behavior classification, step detection, and knee angle calculation was developed. The validation protocol consisted of simulated daily activities in a laboratory environment. The tests were performed with ten healthy subjects and eleven patients with multiple sclerosis. Activity classification showed comparable performance to commercially available activPAL sensors. Step detection with our sensor system was more accurate. The calculated flexion-extension angle of the knee joint showed a root mean square error of less than 5° compared with results obtained using an electro-mechanical goniometer. This new system combines ambulatory behavior assessment and knee angle measurement for long-term measurement periods in a home environment. The wearable sensor system demonstrated high validity for behavior classification and knee joint angle measurement in a laboratory setting.

Clinical applications of immunoglobulin in neuromuscular diseases: focus on inflammatory myopathies

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Paulo Victor Sgobbi de Souza

2014-12-01

Full Text Available During recent years, an increasing number of neuromuscular diseases have been recognized either to be caused primarily by autoimmune mechanisms, or to have important autoimmune components. The involved pathophysiological mechanisms and clinical manifestations have been better recognized and many of these disorders are potentially treatable by immunosuppression or by immunomodulation with intravenous immunoglobulin (IVIg. IVIg has been tried in a variety of immune-mediated neurological diseases, being target of widespread use in central and peripheral nervous systems diseases. Objective To give an overview of the main topics regarding the mechanism of action and different therapeutic uses of IVIg in neurological practice, mainly in neuromuscular diseases.

Knee joint biomechanics and neuromuscular control during gait before and after total knee arthroplasty are sex-specific.

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Astephen Wilson, Janie L; Dunbar, Michael J; Hubley-Kozey, Cheryl L

2015-01-01

The future of total knee arthroplasty (TKA) surgery will involve planning that incorporates more patient-specific characteristics. Despite known biological, morphological, and functional differences between men and women, there has been little investigation into knee joint biomechanical and neuromuscular differences between men and women with osteoarthritis, and none that have examined sex-specific biomechanical and neuromuscular responses to TKA surgery. The objective of this study was to examine sex-associated differences in knee kinematics, kinetics and neuromuscular patterns during gait before and after TKA. Fifty-two patients with end-stage knee OA (28 women, 24 men) underwent gait and neuromuscular analysis within the week prior to and one year after surgery. A number of sex-specific differences were identified which suggest a different manifestation of end-stage knee OA between the sexes. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of a 6-week dynamic neuromuscular training programme on ankle joint function: A Case report.

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O'Driscoll, Jeremiah; Kerin, Fearghal; Delahunt, Eamonn

2011-06-09

Ankle joint sprain and the subsequent development of chronic ankle instability (CAI) are commonly encountered by clinicians involved in the treatment and rehabilitation of musculoskeletal injuries. It has recently been advocated that ankle joint post-sprain rehabilitation protocols should incorporate dynamic neuromuscular training to enhance ankle joint sensorimotor capabilities. To date no studies have reported on the effects of dynamic neuromuscular training on ankle joint positioning during landing from a jump, which has been reported as one of the primary injury mechanisms for ankle joint sprain. This case report details the effects of a 6-week dynamic neuromuscular training programme on ankle joint function in an athlete with CAI. The athlete took part in a progressive 6-week dynamic neuromuscular training programme which incorporated postural stability, strengthening, plyometric, and speed/agility drills. The outcome measures chosen to assess for interventional efficacy were: 1 Cumberland Ankle Instability Tool (CAIT) scores, 2 Star Excursion Balance Test (SEBT) reach distances, 3 ankle joint plantar flexion during drop landing and drop vertical jumping, and 4 ground reaction forces (GRFs) during walking. CAIT and SEBT scores improved following participation in the programme. The angle of ankle joint plantar flexion decreased at the point of initial contact during the drop landing and drop vertical jumping tasks, indicating that the ankle joint was in a less vulnerable position upon landing following participation in the programme. Furthermore, GRFs were reduced whilst walking post-intervention. The 6-week dynamic neuromuscular training programme improved parameters of ankle joint sensorimotor control in an athlete with CAI. Further research is now required in a larger cohort of subjects to determine the effects of neuromuscular training on ankle joint injury risk factors.

Neuromuscular Coordination Deficit Persists 12 Months after ACL Reconstruction But Can Be Modulated by 6 Weeks of Kettlebell Training: A Case Study in Women’s Elite Soccer

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Mette K. Zebis

2017-01-01

Full Text Available The aim of the present single-case study was to investigate the effect of 6 weeks’ kettlebell training on the neuromuscular risk profile for ACL injury in a high-risk athlete returning to sport after ACL reconstruction. A female elite soccer player (age 21 years with no previous history of ACL injury went through neuromuscular screening as measured by EMG preactivity of vastus lateralis and semitendinosus during a standardized sidecutting maneuver. Subsequently, the player experienced a noncontact ACL injury. The player was screened again following postreconstruction rehabilitation, then underwent 6-week kettlebell training, and was subsequently screened again at 6-week follow-up. Prior to and after postreconstruction rehabilitation the player demonstrated a neuromuscular profile during sidecutting known to increase the risk for noncontact ACL injury, that is, reduced EMG preactivity for semitendinosus and elevated EMG preactivity for vastus lateralis. Subsequently, the 6-week kettlebell training increased semitendinosus muscle preactivity during sidecutting by 38 percentage points to a level equivalent to a neuromuscular low-risk profile. An ACL rehabilitated female athlete with a high-risk neuromuscular profile changed to low-risk in response to 6 weeks of kettlebell training. Thus, short-term kettlebell exercise with documented high levels of medial hamstring activation was found to transfer into high medial hamstring preactivation during a sidecutting maneuver.

Active zone proteins are transported via distinct mechanisms regulated by Par-1 kinase.

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Kara R Barber

2017-02-01

Full Text Available Disruption of synapses underlies a plethora of neurodevelopmental and neurodegenerative disease. Presynaptic specialization called the active zone plays a critical role in the communication with postsynaptic neuron. While the role of many proteins at the active zones in synaptic communication is relatively well studied, very little is known about how these proteins are transported to the synapses. For example, are there distinct mechanisms for the transport of active zone components or are they all transported in the same transport vesicle? Is active zone protein transport regulated? In this report we show that overexpression of Par-1/MARK kinase, a protein whose misregulation has been implicated in Autism spectrum disorders (ASDs and neurodegenerative disorders, lead to a specific block in the transport of an active zone protein component- Bruchpilot at Drosophila neuromuscular junctions. Consistent with a block in axonal transport, we find a decrease in number of active zones and reduced neurotransmission in flies overexpressing Par-1 kinase. Interestingly, we find that Par-1 acts independently of Tau-one of the most well studied substrates of Par-1, revealing a presynaptic function for Par-1 that is independent of Tau. Thus, our study strongly suggests that there are distinct mechanisms that transport components of active zones and that they are tightly regulated.

Comparing targeted exome and whole exome approaches for genetic diagnosis of neuromuscular disorders

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Svetlana Gorokhova

2015-12-01

Full Text Available Massively parallel sequencing is rapidly becoming a widely used method in genetic diagnostics. However, there is still no clear consensus as to which approach can most efficiently identify the pathogenic mutations carried by a given patient, while avoiding false negative and false positive results. We developed a targeted exome approach (MyoPanel2 in order to optimize genetic diagnosis of neuromuscular disorders. Using this approach, we were able to analyse 306 genes known to be mutated in myopathies as well as in related disorders, obtaining 98.8% target sequence coverage at 20×. Moreover, MyoPanel2 was able to detect 99.7% of 11,467 known mutations responsible for neuromuscular disorders. We have then used several quality control parameters to compare performance of the targeted exome approach with that of whole exome sequencing. The results of this pilot study of 140 DNA samples suggest that targeted exome sequencing approach is an efficient genetic diagnostic test for most neuromuscular diseases.

Do Psychosocial Interventions Improve Quality of Life and Wellbeing in Adults with Neuromuscular Disorders? A Systematic Review and Narrative Synthesis.

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Walklet, Elaine; Muse, Kate; Meyrick, Jane; Moss, Tim

2016-08-30

Quality of life and well-being are frequently restricted in adults with neuromuscular disorders. As such, identification of appropriate interventions is imperative. The objective of this paper was to systematically review and critically appraise quantitative studies (RCTs, controlled trials and cohort studies) of psychosocial interventions designed to improve quality of life and well-being in adults with neuromuscular disorders. A systematic review of the published and unpublished literature was conducted. Studies meeting inclusion criteria were appraised using a validated quality assessment tool and results presented in a narrative synthesis. Out of 3,136 studies identified, ten studies met criteria for inclusion within the review. Included studies comprised a range of interventions including: cognitive behavioural therapy, dignity therapy, hypnosis, expressive disclosure, gratitude lists, group psychoeducation and psychologically informed rehabilitation. Five of the interventions were for patients with Amyotrophic Lateral Sclerosis (ALS). The remainder were for patients with post-polio syndrome, muscular dystrophies and mixed disorders, such as Charcot-Marie-Tooth disease, myasthenia gravis and myotonic dystrophy. Across varied interventions and neuromuscular disorders, seven studies reported a short-term beneficial effect of intervention on quality of life and well-being. Whilst such findings are encouraging, widespread issues with the methodological quality of these studies significantly compromised the results. There is no strong evidence that psychosocial interventions improve quality of life and well-being in adults with neuromuscular disorders, due to a paucity of high quality research in this field. Multi-site, randomised controlled trials with active controls, standardised outcome measurement and longer term follow-ups are urgently required.

Neuromuscular strategies for lumbopelvic control during frontal and sagittal plane movement challenges differ between people with and without low back pain.

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Nelson-Wong, E; Poupore, K; Ingvalson, S; Dehmer, K; Piatte, A; Alexander, S; Gallant, P; McClenahan, B; Davis, A M

2013-12-01

Observation-based assessments of movement are a standard component in clinical assessment of patients with non-specific low back pain. While aberrant motion patterns can be detected visually, clinicians are unable to assess underlying neuromuscular strategies during these tests. The purpose of this study was to compare coordination of the trunk and hip muscles during 2 commonly used assessments for lumbopelvic control in people with low back pain (LBP) and matched control subjects. Electromyography was recorded from hip and trunk muscles of 34 participants (17 with LBP) during performance of the Active Hip Abduction (AHAbd) and Active Straight Leg Raise (ASLR) tests. Relative muscle timing was calculated using cross-correlation. Participants with LBP demonstrated a variable strategy, while control subjects used a consistent proximal to distal activation strategy during both frontal and sagittal plane movements. Findings from this study provide insight into underlying neuromuscular control during commonly used assessment tests for patients with LBP that may help to guide targeted intervention approaches. Copyright © 2013 Elsevier Ltd. All rights reserved.

Time course and dimensions of postural control changes following neuromuscular training in youth field hockey athletes.

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Zech, Astrid; Klahn, Philipp; Hoeft, Jon; zu Eulenburg, Christine; Steib, Simon

2014-02-01

Injury prevention effects of neuromuscular training have been partly attributed to postural control adaptations. Uncertainty exists regarding the magnitude of these adaptations and on how they can be adequately monitored. The objective was to determine the time course of neuromuscular training effects on functional, dynamic and static balance measures. Thirty youth (14.9 ± 3 years) field hockey athletes were randomised to an intervention or control group. The intervention included a 20-min neuromuscular warm-up program performed twice weekly for 10 weeks. Balance assessments were performed at baseline, week three, week six and post-intervention. They included the star excursion balance test (SEBT), balance error scoring system (BESS), jump-landing time to stabilization (TTS) and center of pressure (COP) sway velocity during single-leg standing. No baseline differences were found between groups in demographic data and balance measures. Adherence was at 86%. All balance measures except the medial-lateral TTS improved significantly over time (p controls (31.8 ± 22.1%). There were no significant group by time interactions in the SEBT, TTS and COP sway velocity. Neuromuscular training was effective in improving postural control in youth team athletes. However, this effect was not reflected in all balance measures suggesting that the neuromuscular training did not influence all dimensions of postural control. Further studies are needed to confirm the potential of specific warm-up programs to improve postural control.

Estimulação elétrica neuromuscular na disfunção patelofemoral: revisão de literatura Neuromuscular electric stimulation in patellofemoral dysfunction: riterature review

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Ricardo Lucas dos Santos

2013-02-01

Full Text Available A disfunção femoropatelar é uma deficiência bastante comum entre indivíduos jovens que acomete, principalmente, o sexo feminino e pode ser caracterizada por dor, edema e creptação retropatelar. Sistematizar o conhecimento em relação ao aumento da força muscular do quadríceps e alívio de dor em pacientes com disfunção femoropatelar, através da utilização da estimulação elétrica neuromuscular e exercícios resistidos. Trata se de um estudo de revisão narrativa da literatura no período de 2005 a 2011. Os critérios de inclusão foram artigos de intervenção, dos últimos seis anos, nos idiomas inglês, espanhol e português, que utilizaram o fortalecimento muscular e a eletroestimulação neuromuscular para reabilitação obtidos através de buscas nos bancos de dados eletrônicos Medline, Lilacs e na biblioteca Bireme. A busca bibliográfica resultou em 28 referências, destes foram excluídos nove de acordo com os objetivos e critérios de inclusão e foram selecionados 16 artigos para leitura dos resumos e posterior análise. A Estimulação Elétrica Neuromuscular (EENM de média frequência pode ser utilizada associada a exercícios resistidos como coadjuvante no tratamento da disfunção femoropatelar (DFP, tanto para se obter um reequilíbrio muscular quanto para o alívio da dor.Patellofemoral dysfunction is a fairly common deficiency among young individuals that primarily affects females and may be characterized by pain, swelling and retropatellar crepitation. The purpose of this review of literature from the period between 2005 and 2011 was to systematize knowledge in relation to the increase in quadriceps muscle strength and pain relief in patients with patellofemoral dysfunction, using neuromuscular electrical stimulation and resistance exercises. The inclusion criteria were intervention articles from the past six years, in English, Spanish and Portuguese, which used muscle strengthening and neuromuscular

Pseudomonas aeruginosa alkaline protease blocks complement activation via the classical and lectin pathways.

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Laarman, Alexander J; Bardoel, Bart W; Ruyken, Maartje; Fernie, Job; Milder, Fin J; van Strijp, Jos A G; Rooijakkers, Suzan H M

2012-01-01

The complement system rapidly detects and kills Gram-negative bacteria and supports bacterial killing by phagocytes. However, bacterial pathogens exploit several strategies to evade detection by the complement system. The alkaline protease (AprA) of Pseudomonas aeruginosa has been associated with bacterial virulence and is known to interfere with complement-mediated lysis of erythrocytes, but its exact role in bacterial complement escape is unknown. In this study, we analyzed how AprA interferes with complement activation and whether it could block complement-dependent neutrophil functions. We found that AprA potently blocked phagocytosis and killing of Pseudomonas by human neutrophils. Furthermore, AprA inhibited opsonization of bacteria with C3b and the formation of the chemotactic agent C5a. AprA specifically blocked C3b deposition via the classical and lectin pathways, whereas the alternative pathway was not affected. Serum degradation assays revealed that AprA degrades both human C1s and C2. However, repletion assays demonstrated that the mechanism of action for complement inhibition is cleavage of C2. In summary, we showed that P. aeruginosa AprA interferes with classical and lectin pathway-mediated complement activation via cleavage of C2.

Muscles in a mouse model of spinal muscular atrophy show profound defects in neuromuscular development even in the absence of failure in neuromuscular transmission or loss of motor neurons.

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Lee, Young Il; Mikesh, Michelle; Smith, Ian; Rimer, Mendell; Thompson, Wesley

2011-08-15

A mouse model of the devastating human disease "spinal muscular atrophy" (SMA) was used to investigate the severe muscle weakness and spasticity that precede the death of these animals near the end of the 2nd postnatal week. Counts of motor units to the soleus muscle as well as of axons in the soleus muscle nerve showed no loss of motor neurons. Similarly, neither immunostaining of neuromuscular junctions nor the measurement of the tension generated by nerve stimulation gave evidence of any significant impairment in neuromuscular transmission, even when animals were maintained up to 5days longer via a supplementary diet. However, the muscles were clearly weaker, generating less than half their normal tension. Weakness in 3 muscles examined in the study appears due to a severe but uniform reduction in muscle fiber size. The size reduction results from a failure of muscle fibers to grow during early postnatal development and, in soleus, to a reduction in number of fibers generated. Neuromuscular development is severely delayed in these mutant animals: expression of myosin heavy chain isoforms, the elimination of polyneuronal innervation, the maturation in the shape of the AChR plaque, the arrival of SCs at the junctions and their coverage of the nerve terminal, the development of junctional folds. Thus, if SMA in this particular mouse is a disease of motor neurons, it can act in a manner that does not result in their death or disconnection from their targets but nonetheless alters many aspects of neuromuscular development. Copyright © 2011 Elsevier Inc. All rights reserved.

Visualization of the distribution of surface-active block copolymers in PDMS-based coatings

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Noguer, A. Camós; Latipov, R.; Madsen, F. B.

2018-01-01

the distribution and release of these block copolymers from PDMS-based coatings has been previously reported. However, the distribution and behaviour of these compounds in the bulk of the PDMS coating are not fully understood. A novel fluorescent-labelled triblock PEG-b-PDMS-b-PEG copolymer was synthesized...... results in non-specific protein adsorption and wettability issues. Poly(ethylene glycol)-based surface-active block copolymers and surfactants have been added to PDMS coatings and films to impart biofouling resistance and hydrophilicity to the PDMS surface with successful results. Information regarding...

The effects of neuromuscular exercise on medial knee joint load post-arthroscopic partial medial meniscectomy: 'SCOPEX', a randomised control trial protocol.

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Hall, Michelle; Hinman, Rana S; Wrigley, Tim V; Roos, Ewa M; Hodges, Paul W; Staples, Margaret; Bennell, Kim L

2012-11-27

Meniscectomy is a risk factor for knee osteoarthritis, with increased medial joint loading a likely contributor to the development and progression of knee osteoarthritis in this group. Therefore, post-surgical rehabilitation or interventions that reduce medial knee joint loading have the potential to reduce the risk of developing or progressing osteoarthritis. The primary purpose of this randomised, assessor-blind controlled trial is to determine the effects of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee joint load during functional tasks in people who have recently undergone a partial medial meniscectomy. 62 people aged 30-50 years who have undergone an arthroscopic partial medial meniscectomy within the previous 3 to 12 months will be recruited and randomly assigned to a neuromuscular exercise or control group using concealed allocation. The neuromuscular exercise group will attend 8 supervised exercise sessions with a physiotherapist and will perform 6 exercises at home, at least 3 times per week for 12 weeks. The control group will not receive the neuromuscular training program. Blinded assessment will be performed at baseline and immediately following the 12-week intervention. The primary outcomes are change in the peak external knee adduction moment measured by 3-dimensional analysis during normal paced walking and one-leg rise. Secondary outcomes include the change in peak external knee adduction moment during fast pace walking and one-leg hop and change in the knee adduction moment impulse during walking, one-leg rise and one-leg hop, knee and hip muscle strength, electromyographic muscle activation patterns, objective measures of physical function, as well as self-reported measures of physical function and symptoms and additional biomechanical parameters. The findings from this trial will provide evidence regarding the effect of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee

Effect of temperature on spontaneous release of transmitter at the mammalian neuromuscular junction

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Duncan, C J; Statham, H E

1977-01-01

Temperature has a multifactorial effect on miniature endplate potential (MEPP) frequency at the mammalian neuromuscular junction, with a negative Q/sub 10/ at 14--28/sup 0/C. The results are explained in terms of the effect of temperature on the various factors that control (Ca/sup 2/+sub i/ at the presynaptic terminals. The temperature-sensitivity of the Ca/sup 2 +/-transport enzyme is believed to be of particular significance and accounts for the observed differences between the amphibian and mammalian neuromuscular junctions.

Effects of Muscle Fatigue, Creep, and Musculoskeletal Pain on Neuromuscular Responses to Unexpected Perturbation of the Trunk: A Systematic Review.

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Abboud, Jacques; Lardon, Arnaud; Boivin, Frédéric; Dugas, Claude; Descarreaux, Martin

2016-01-01

Introduction: Trunk neuromuscular responses have been shown to adapt under the influence of muscle fatigue, as well as spinal tissue creep or even with the presence of low back pain (LBP). Despite a large number of studies exploring how these external perturbations affect the spinal stability, characteristics of such adaptations remains unclear. Aim: The purpose of this systematic review was to assess the quality of evidence of studies investigating trunk neuromuscular responses to unexpected trunk perturbation. More specifically, the targeted neuromuscular responses were trunk muscle activity reflex and trunk kinematics under the influence of muscle fatigue, spinal creep, and musculoskeletal pain. Methods: A research of the literature was conducted in Pubmed, Embase, and Sport-Discus databases using terms related to trunk neuromuscular reflex responses, measured by electromyography (baseline activity, reflex latency, and reflex amplitude) and/or trunk kinematic, in context of unexpected external perturbation. Moreover, independent variables must be either trunk muscle fatigue or spinal tissue creep or LBP. All included articles were scored for their electromyography methodology based on the "Surface Electromyography for the Non-Invasive Assessment of Muscles (SENIAM)" and the "International Society of Electrophysiology and Kinesiology (ISEK)" recommendations whereas overall quality of articles was scored using a specific quality checklist modified from the Quality Index. Meta-analysis was performed on reflex latency variable. Results: A final set of 29 articles underwent quality assessments. The mean quality score was 79%. No effect of muscle fatigue on erector spinae reflex latency following an unexpected perturbation, nor any other distinctive effects was found for back muscle fatigue and reflex parameters. As for spinal tissue creep effects, no alteration was found for any of the trunk reflex variables. Finally, the meta-analysis revealed an increased erector

FUTSAL MATCH-RELATED FATIGUE AFFECTS RUNNING PERFORMANCE AND NEUROMUSCULAR PARAMETERS BUT NOT FINISHING KICK SPEED OR ACCURACY

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Fabio Milioni

2016-11-01

Full Text Available Purpose: The aim of the present study was to investigate the influence of futsal match-related fatigue on running performance, neuromuscular variables, and finishing kick speed and accuracy. Methods: Ten professional futsal players participated in the study (age: 22.2±2.5 years; and initially performed an incremental protocol to determine maximum oxygen uptake (VO2max : 50.6±4.9 mL.kg-1.min-1. Next, simulated games were performed, in four periods of 10 min during which heart rate and blood lactate concentration were monitored. The entire games were video recorded for subsequent automatic tracking. Before and immediately after the simulated game, neuromuscular function was measured by maximal isometric force of knee extension, voluntary activation using twitch interpolation technique, and electromyographic activity. Before, at half time, and immediately after the simulated game, the athletes also performed a set of finishing kicks for ball speed and accuracy measurements. Results: Total distance covered (1st half: 1986.6±74.4 m; 2nd half: 1856.0±129.7 m – P=0.00 and distance covered per minute (1st half: 103.2±4.4 m.min-1; 2nd half: 96.4±7.5 m.min-1 – P=0.00 demonstrated significant declines during the simulated game, as well as maximal isometric force of knee extension (Before: 840.2±66.2 N; After: 751.6±114.3 N – P=0.04 and voluntary activation (Before: 85.9±7.5%; After: 74.1±12.3% – P=0.04, however ball speed and accuracy during the finishing kicks were not significantly affected.Conclusion: Therefore, we conclude that despite the decline in running performance and neuromuscular variables presenting an important manifestation of central fatigue, this condition apparently does not affect the speed and accuracy of finishing kicks.

Effects of Increasing Neuromuscular Electrical Stimulation Current Intensity on Cortical Sensorimotor Network Activation: A Time Domain fNIRS Study.

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Makii Muthalib

Full Text Available Neuroimaging studies have shown neuromuscular electrical stimulation (NMES-evoked movements activate regions of the cortical sensorimotor network, including the primary sensorimotor cortex (SMC, premotor cortex (PMC, supplementary motor area (SMA, and secondary somatosensory area (S2, as well as regions of the prefrontal cortex (PFC known to be involved in pain processing. The aim of this study, on nine healthy subjects, was to compare the cortical network activation profile and pain ratings during NMES of the right forearm wrist extensor muscles at increasing current intensities up to and slightly over the individual maximal tolerated intensity (MTI, and with reference to voluntary (VOL wrist extension movements. By exploiting the capability of the multi-channel time domain functional near-infrared spectroscopy technique to relate depth information to the photon time-of-flight, the cortical and superficial oxygenated (O2Hb and deoxygenated (HHb hemoglobin concentrations were estimated. The O2Hb and HHb maps obtained using the General Linear Model (NIRS-SPM analysis method, showed that the VOL and NMES-evoked movements significantly increased activation (i.e., increase in O2Hb and corresponding decrease in HHb in the cortical layer of the contralateral sensorimotor network (SMC, PMC/SMA, and S2. However, the level and area of contralateral sensorimotor network (including PFC activation was significantly greater for NMES than VOL. Furthermore, there was greater bilateral sensorimotor network activation with the high NMES current intensities which corresponded with increased pain ratings. In conclusion, our findings suggest that greater bilateral sensorimotor network activation profile with high NMES current intensities could be in part attributable to increased attentional/pain processing and to increased bilateral sensorimotor integration in these cortical regions.

Effects of Increasing Neuromuscular Electrical Stimulation Current Intensity on Cortical Sensorimotor Network Activation: A Time Domain fNIRS Study.

Science.gov (United States)

Muthalib, Makii; Re, Rebecca; Zucchelli, Lucia; Perrey, Stephane; Contini, Davide; Caffini, Matteo; Spinelli, Lorenzo; Kerr, Graham; Quaresima, Valentina; Ferrari, Marco; Torricelli, Alessandro

2015-01-01

Neuroimaging studies have shown neuromuscular electrical stimulation (NMES)-evoked movements activate regions of the cortical sensorimotor network, including the primary sensorimotor cortex (SMC), premotor cortex (PMC), supplementary motor area (SMA), and secondary somatosensory area (S2), as well as regions of the prefrontal cortex (PFC) known to be involved in pain processing. The aim of this study, on nine healthy subjects, was to compare the cortical network activation profile and pain ratings during NMES of the right forearm wrist extensor muscles at increasing current intensities up to and slightly over the individual maximal tolerated intensity (MTI), and with reference to voluntary (VOL) wrist extension movements. By exploiting the capability of the multi-channel time domain functional near-infrared spectroscopy technique to relate depth information to the photon time-of-flight, the cortical and superficial oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin concentrations were estimated. The O2Hb and HHb maps obtained using the General Linear Model (NIRS-SPM) analysis method, showed that the VOL and NMES-evoked movements significantly increased activation (i.e., increase in O2Hb and corresponding decrease in HHb) in the cortical layer of the contralateral sensorimotor network (SMC, PMC/SMA, and S2). However, the level and area of contralateral sensorimotor network (including PFC) activation was significantly greater for NMES than VOL. Furthermore, there was greater bilateral sensorimotor network activation with the high NMES current intensities which corresponded with increased pain ratings. In conclusion, our findings suggest that greater bilateral sensorimotor network activation profile with high NMES current intensities could be in part attributable to increased attentional/pain processing and to increased bilateral sensorimotor integration in these cortical regions.

Effect of a 6-week dynamic neuromuscular training programme on ankle joint function: A Case report

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O'Driscoll Jeremiah

2011-06-01

Full Text Available Abstract Background Ankle joint sprain and the subsequent development of chronic ankle instability (CAI are commonly encountered by clinicians involved in the treatment and rehabilitation of musculoskeletal injuries. It has recently been advocated that ankle joint post-sprain rehabilitation protocols should incorporate dynamic neuromuscular training to enhance ankle joint sensorimotor capabilities. To date no studies have reported on the effects of dynamic neuromuscular training on ankle joint positioning during landing from a jump, which has been reported as one of the primary injury mechanisms for ankle joint sprain. This case report details the effects of a 6-week dynamic neuromuscular training programme on ankle joint function in an athlete with CAI. Methods The athlete took part in a progressive 6-week dynamic neuromuscular training programme which incorporated postural stability, strengthening, plyometric, and speed/agility drills. The outcome measures chosen to assess for interventional efficacy were: 1 Cumberland Ankle Instability Tool (CAIT scores, 2 Star Excursion Balance Test (SEBT reach distances, 3 ankle joint plantar flexion during drop landing and drop vertical jumping, and 4 ground reaction forces (GRFs during walking. Results CAIT and SEBT scores improved following participation in the programme. The angle of ankle joint plantar flexion decreased at the point of initial contact during the drop landing and drop vertical jumping tasks, indicating that the ankle joint was in a less vulnerable position upon landing following participation in the programme. Furthermore, GRFs were reduced whilst walking post-intervention. Conclusions The 6-week dynamic neuromuscular training programme improved parameters of ankle joint sensorimotor control in an athlete with CAI. Further research is now required in a larger cohort of subjects to determine the effects of neuromuscular training on ankle joint injury risk factors.

Effect of a 6-week dynamic neuromuscular training programme on ankle joint function: A Case report

LENUS (Irish Health Repository)

O'Driscoll, Jeremiah

2011-06-09

Abstract Background Ankle joint sprain and the subsequent development of chronic ankle instability (CAI) are commonly encountered by clinicians involved in the treatment and rehabilitation of musculoskeletal injuries. It has recently been advocated that ankle joint post-sprain rehabilitation protocols should incorporate dynamic neuromuscular training to enhance ankle joint sensorimotor capabilities. To date no studies have reported on the effects of dynamic neuromuscular training on ankle joint positioning during landing from a jump, which has been reported as one of the primary injury mechanisms for ankle joint sprain. This case report details the effects of a 6-week dynamic neuromuscular training programme on ankle joint function in an athlete with CAI. Methods The athlete took part in a progressive 6-week dynamic neuromuscular training programme which incorporated postural stability, strengthening, plyometric, and speed\\/agility drills. The outcome measures chosen to assess for interventional efficacy were: 1 Cumberland Ankle Instability Tool (CAIT) scores, 2 Star Excursion Balance Test (SEBT) reach distances, 3 ankle joint plantar flexion during drop landing and drop vertical jumping, and 4 ground reaction forces (GRFs) during walking. Results CAIT and SEBT scores improved following participation in the programme. The angle of ankle joint plantar flexion decreased at the point of initial contact during the drop landing and drop vertical jumping tasks, indicating that the ankle joint was in a less vulnerable position upon landing following participation in the programme. Furthermore, GRFs were reduced whilst walking post-intervention. Conclusions The 6-week dynamic neuromuscular training programme improved parameters of ankle joint sensorimotor control in an athlete with CAI. Further research is now required in a larger cohort of subjects to determine the effects of neuromuscular training on ankle joint injury risk factors.

Neuromuscular blockade for improvement of surgical conditions during laparotomy

DEFF Research Database (Denmark)

Madsen, Matias Vested; Scheppan, Susanne; Kissmeyer, Peter

2015-01-01

neuromuscular blockade (NMB), defined as a post-tetanic-count (PTC) of 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesised that deep NMB (PTC 0-1) would improve surgical conditions during upper laparotomy as compared to standard NMB with bolus administration. METHODS...

Sex differences in kinetic and neuromuscular control during jumping and landing

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Márquez, G.; Alegre, L.M.; Jaén, D.; Martin-Casado, L.; Aguado, X.

2017-01-01

In the present study, we analysed the kinetic profile together with the lower limb EMG activation pattern during a countermovement jump and its respective landing phase in males and females. Twenty subjects (10 males and 10 females) took part in the study. One experimental session was conducted in order to record kinetic and electromyographic (EMG) parameters during a countermovement jump (CMJ) and the subsequent landing phase. During the CMJ, males recorded a higher (ppush-off phase. During landings males showed higher (p<0.01) peak ground reaction forces (Fpeak), greater (p<0.05) stiffness and a higher maximal displacement of the CoM (p<0.05) than females. EMG analysis revealed greater EMG activity in the tibialis anterior (p<0.05) and rectus femoris (p=0.05) muscles in males. Higher plantar flexor co-activation during landing has also been found in males. Our findings demonstrated different neuromuscular control in males and females during jumping and landing. PMID:28250245

Manejo de longo prazo em crianças com transtornos neuromusculares Long-term management of children with neuromuscular disorders

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Eugen-Matthias Strehle

2009-10-01

Full Text Available OBJETIVO: A distrofia muscular de Duchenne é o tipo mais comum de miopatia genética. Contudo, existe um grande número de doenças neuromusculares hereditárias que são individualmente muito raras e sobre as quais não há muita informação clínica disponível. Este artigo de revisão baseia-se na experiência do autor em uma clínica pediátrica para tratamento de doenças musculares e apresenta orientação prática e planos terapêuticos para os problemas frequentemente encontrados. FONTES DE DADOS: O banco de dados da MEDLINE foi pesquisado com o objetivo de localizar artigos recentes e relevantes para o manejo de crianças com miopatias e neuropatias hereditárias. Uma coorte de 200 pacientes foi avaliada através de análise estatística descritiva. SÍNTESE DOS DADOS: A distrofia muscular de Duchenne representou quase metade dos diagnósticos, seguida da atrofia muscular espinhal (12%, da distrofia muscular de Becker e da distrofia miotônica (7% cada. Dezesseis pacientes (9% apresentaram miopatia de origem desconhecida. CONCLUSÕES: Assim como ocorre com outras doenças crônicas, esses pacientes devem passar por acompanhamento periódico realizado por profissionais de saúde desde cedo para aumentar sua expectativa de vida e melhorar sua qualidade de vida. É útil para os médicos adotarem uma abordagem estruturada ao atender crianças com transtornos neuromusculares e monitorar todos os sistemas de órgãos afetados.OBJECTIVE: Duchenne muscular dystrophy is the commonest genetic myopathy but there exist a large number of inherited neuromuscular diseases which individually are very rare and where clinical information is not widely available. This review is based on the author's experience in a pediatric muscle clinic and provides practical guidance and treatment plans for frequently encountered problems. SOURCES: A MEDLINE search was conducted to retrieve recent articles relevant to the management of children with

Sleep-Disordered Breathing in Neuromuscular Disease: Diagnostic and Therapeutic Challenges.

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Aboussouan, Loutfi S; Mireles-Cabodevila, Eduardo

2017-10-01

Normal sleep-related rapid eye movement sleep atonia, reduced lung volumes, reduced chemosensitivity, and impaired airway dilator activity become significant vulnerabilities in the setting of neuromuscular disease. In that context, the compounding effects of respiratory muscle weakness and disease-specific features that promote upper airway collapse or cause dilated cardiomyopathy contribute to various sleep-disordered breathing events. The reduction in lung volumes with neuromuscular disease is further compromised by sleep and the supine position, exaggerating the tendency for upper airway collapse and desaturation with sleep-disordered breathing events. The most commonly identified events are diaphragmatic/pseudo-central, due to a decrease in the rib cage contribution to the tidal volume during phasic rapid eye movement sleep. Obstructive and central sleep apneas are also common. Noninvasive ventilation can improve survival and quality of sleep but should be used with caution in the context of dilated cardiomyopathy or significant bulbar symptoms. Noninvasive ventilation can also trigger sleep-disordered breathing events, including ineffective triggering, autotriggering, central sleep apnea, and glottic closure, which compromise the potential benefits of the intervention by increasing arousals, reducing adherence, and impairing sleep architecture. Polysomnography plays an important diagnostic and therapeutic role by correctly categorizing sleep-disordered events, identifying sleep-disordered breathing triggered by noninvasive ventilation, and improving noninvasive ventilation settings. Optimal management may require dedicated hypoventilation protocols and a technical staff well versed in the identification and troubleshooting of respiratory events. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Sleep Extension before Sleep Loss: Effects on Performance and Neuromuscular Function.

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Arnal, Pierrick J; Lapole, Thomas; Erblang, Mégane; Guillard, Mathias; Bourrilhon, Cyprien; Léger, Damien; Chennaoui, Mounir; Millet, Guillaume Y

2016-08-01

This study aimed to investigate the effects of six nights of sleep extension on motor performance and associated neuromuscular function before and after one night of total sleep deprivation (TSD). Twelve healthy men participated in two experimental conditions (randomized crossover design): extended sleep (EXT, 9.8 ± 0.1 h time in bed) and habitual sleep (HAB, 8.2 ± 0.1 h time in bed). In each condition, subjects performed six nights of either EXT or HAB at home followed by an assessment of motor performance and neuromuscular function at baseline (D0) and after one night of TSD, i.e., 34-37 h of continuous wakefulness (D1). Maximal voluntary contractions with superimposed femoral nerve electrical and transcranial magnetic stimulations and stimulations on relaxed muscles were investigated before and after submaximal isometric knee extensor exercises performed until task failure. Time to exhaustion was longer in EXT compared with HAB (+3.9% ± 7.7% and +8.1% ± 12.3% at D0 and D1, respectively). Performance at D1 decreased from D0 similarly between conditions (-7.2% ± 5.6% and -3.7% ± 7.3% in HAB and EXT, respectively). At D1, the RPE during exercise was lower in EXT compared with HAB (-7.2% ± 7.5%) with no difference at D0. No difference was observed in voluntary activation between the two conditions. Six nights of sleep extension improved sustained contraction time to exhaustion, and this result cannot be explained by smaller reductions in voluntary activation, measured by both nerve and transcranial magnetic stimulation. The beneficial effect on motor performance in the EXT condition was likely due to reduced RPE after TSD.

Acetylcholine-induced inhibition of presynaptic calcium signals and transmitter release in the frog neuromuscular junction

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Eduard Khaziev

2016-12-01

Full Text Available Acetylcholine (ACh, released from axonal terminals of motor neurones in neuromuscular junctions regulates the efficacy of neurotransmission through activation of presynaptic nicotinic and muscarinic autoreceptors. Receptor-mediated presynaptic regulation could reflect either direct action on exocytotic machinery or modulation of Ca2+ entry and resulting intra-terminal Ca2+ dynamics. We have measured free intra-terminal cytosolic Ca2+ ([Ca2+]i using Oregon-Green 488 microfluorimetry, in parallel with voltage-clamp recordings of spontaneous (mEPC and evoked (EPC postsynaptic currents in post-junctional skeletal muscle fibre. Activation of presynaptic muscarinic and nicotinic receptors with exogenous acetylcholine and its non-hydrolized analogue carbachol reduced amplitude of the intra-terminal [Ca2+]i transients and decreased quantal content (calculated by dividing the area under EPC curve by the area under mEPC curve. Pharmacological analysis revealed the role of muscarinic receptors of M2 subtype as well as d-tubocurarine-sensitive nicotinic receptor in presynaptic modulation of [Ca2+]i transients. Modulation of synaptic transmission efficacy by ACh receptors was completely eliminated by pharmacological inhibition of N-type Ca2+ channels. We conclude that ACh receptor-mediated reduction of Ca2+ entry into the nerve terminal through N-type Ca2+ channels represents one of possible mechanism of presynaptic modulation in frog neuromuscular junction.

Anaesthesia for the patient with dementia undergoing outpatient surgery

DEFF Research Database (Denmark)

Funder, Kamilia S; Steinmetz, Jacob; Rasmussen, Lars S

2009-01-01

, as documented in elderly patients. Neuromuscular blocking agents, and especially rocuronium, display an increased variability in the duration of action, but the new drug sugammadex may reverse the neuromuscular block in a few minutes. Postoperative cognitive decline is more frequent in elderly patients...

Neuromuscular stimulation after stroke: from technology to clinical deployment

NARCIS (Netherlands)

IJzerman, Maarten Joost; Renzenbrink, Gerbert J.; Geurts, Alexander C.H.

2009-01-01

Since the early 1960s, electrical or neuromuscular electrical stimulation (NMES) has been used to support the rehabilitation of stroke patients. One of the earliest applications of NMES included the use of external muscle stimulation to correct drop-foot after stroke. During the last few decades

Roles of neuro-exocytotic proteins at the neuromuscular junction

NARCIS (Netherlands)

Sons-Michel, Michèle S.

2011-01-01

The aim of the studies described in the thesis was to elucidate the roles of several neuro-exocytotic proteins at the motor nerve terminal in neuromuscular synaptic transmission, making use of genetic knockout (KO) mice, each missing one (or more) neuro-exocytotic proteins. In addition, it was

Porous concrete block as an environmental enrichment device increases activity of laying hens in cages.

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Holcman, A; Gorjanc, G; Stuhec, I

2008-09-01

The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible

Neuromuscular adjustments of the quadriceps muscle after repeated cycling sprints.

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Olivier Girard

Full Text Available PURPOSE: This study investigated the supraspinal processes of fatigue of the quadriceps muscle in response to repeated cycling sprints. METHODS: Twelve active individuals performed 10 × 6-s "all-out" sprints on a cycle ergometer (recovery = 30 s, followed 6 min later by 5 × 6-s sprints (recovery = 30 s. Transcranial magnetic and electrical femoral nerve stimulations during brief (5-s and sustained (30-s isometric contractions of the knee extensors were performed before and 3 min post-exercise. RESULTS: Maximal strength of the knee extensors decreased during brief and sustained contractions (~11% and 9%, respectively; P0.05. While cortical voluntary activation declined (P 40% reduced (P<0.001 following exercise. CONCLUSION: The capacity of the motor cortex to optimally drive the knee extensors following a repeated-sprint test was shown in sustained, but not brief, maximal isometric contractions. Additionally, peripheral factors were largely involved in the exercise-induced impairment in neuromuscular function, while corticospinal excitability was well-preserved.

Premature awakening and underuse of neuromuscular monitoring in a registry of patients with butyrylcholinesterase deficiency

DEFF Research Database (Denmark)

Thomsen, J L; Nielsen, C V; Palmqvist, D F

2015-01-01

, neuromuscular monitoring, and postoperative respiratory complications, defined as arterial oxygen desaturation prematurely awakened if anaesthesia had been terminated while the patient was still...... paralysed. RESULTS: We included 123 patients. Neuromuscular monitoring was applied before awakening in 48 (39%) patients. A nerve stimulator was never used or only after attempted awakening in the remaining 75 (61%) patients. Premature awakening occurred in 75 (100%) and 14 (29%) of the unmonitored...

Etiology and Recovery of Neuromuscular Fatigue following Competitive Soccer Match-Play

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Callum G. Brownstein

2017-10-01

Full Text Available Aim: Previous research into the etiology of neuromuscular fatigue following competitive soccer match-play has primarily focused on peripheral perturbations, with limited research assessing central nervous system function in the days post-match. The aim of the present study was to examine the contribution and time-course of recovery of central and peripheral factors toward neuromuscular fatigue following competitive soccer match-play.Methods: Sixteen male semi-professional soccer players completed a 90-min soccer match. Pre-, post- and at 24, 48, and 72 h participants completed a battery of neuromuscular, physical, and perceptual tests. Maximal voluntary contraction force (MVC and twitch responses to electrical (femoral nerve and transcranial magnetic stimulation (TMS of the motor cortex during isometric knee-extension and at rest were measured to assess central nervous system (voluntary activation, VA and muscle contractile (potentiated twitch force, Qtw, pot function. Electromyography responses of the rectus femoris to single- and paired-pulse TMS were used to assess corticospinal excitability and short-interval intracortical inhibition (SICI, respectively. Fatigue and perceptions of muscle soreness were assessed via visual analog scales, and physical function was assessed through measures of jump (countermovement jump height and reactive strength index and sprint performance.Results: Competitive match-play elicited significant post-match declines in MVC force (−14%, P < 0.001 that persisted for 48 h (−4%, P = 0.01, before recovering by 72 h post-exercise. VA (motor point stimulation was reduced immediately post-match (−8%, P < 0.001, and remained depressed at 24 h (−5%, P = 0.01 before recovering by 48 h post-exercise. Qtw,pot was reduced post-match (−14%, P < 0.001, remained depressed at 24 h (−6%, P = 0.01, before recovering by 48 h post-exercise. No changes were evident in corticospinal excitability or SICI. Jump performance

Does mental exertion alter maximal muscle activation?

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Vianney eRozand

2014-09-01

Full Text Available Mental exertion is known to impair endurance performance, but its effects on neuromuscular function remain unclear. The purpose of this study was to test the hypothesis that mental exertion reduces torque and muscle activation during intermittent maximal voluntary contractions of the knee extensors. Ten subjects performed in a randomized order three separate mental exertion conditions lasting 27 minutes each: i high mental exertion (incongruent Stroop task, ii moderate mental exertion (congruent Stroop task, iii low mental exertion (watching a movie. In each condition, mental exertion was combined with ten intermittent maximal voluntary contractions of the knee extensor muscles (one maximal voluntary contraction every 3 minutes. Neuromuscular function was assessed using electrical nerve stimulation. Maximal voluntary torque, maximal muscle activation and other neuromuscular parameters were similar across mental exertion conditions and did not change over time. These findings suggest that mental exertion does not affect neuromuscular function during intermittent maximal voluntary contractions of the knee extensors.

Feeding and Swallowing Disorders in Pediatric Neuromuscular Diseases: An Overview.

Science.gov (United States)

van den Engel-Hoek, Lenie; de Groot, Imelda J M; de Swart, Bert J M; Erasmus, Corrie E

2015-11-20

Feeding and swallowing problems in infants and children have a great impact on health and wellbeing. The aim of this study was to provide an overview of recognized feeding and swallowing problems in different groups of children with neuromuscular diseases, based on relevant literature and expert opinion, and to propose recommendations for the assessment and treatment of these problems. Almost all pediatric neuromuscular diseases are accompanied by feeding and swallowing problems during the different phases of deglutition, problems that give rise to a wide variety of signs and symptoms, which emphasizes the importance of a comprehensive feeding and swallowing assessment by a speech and language therapist.

Motor neuron, nerve, and neuromuscular junction disease.

Science.gov (United States)

Finsterer, Josef; Papić, Lea; Auer-Grumbach, Michaela

2011-10-01

The aim is to review the most relevant findings published during the last year concerning clinical, genetic, pathogenic, and therapeutic advances in motor neuron disease, neuropathies, and neuromuscular junction disorders. Studies on animal and cell models have improved the understanding of how mutated survival motor neuron protein in spinal muscular atrophy governs the pathogenetic processes. New phenotypes of SOD1 mutations have been described. Moreover, animal models enhanced the insight into the pathogenetic background of sporadic and familial amyotrophic lateral sclerosis. Novel treatment options for motor neuron disease have been described in humans and animal models. Considerable progress has been achieved also in elucidating the genetic background of many forms of inherited neuropathies and high clinical and genetic heterogeneity has been demonstrated. Mutations in MuSK and GFTP1 have been shown to cause new types of congenital myasthenic syndromes. A third type of autoantibodies (Lrp4) has been detected to cause myasthenia gravis. Advances in the clinical and genetic characterization of motor neuron diseases, neuropathies, and neuromuscular transmission defects have important implications on the fundamental understanding, diagnosis, and management of these disorders. Identification of crucial steps of the pathogenetic process may provide the basis for the development of novel therapeutic strategies.

Learning disabilities in neuromuscular disorders: a springboard for adult life.

Science.gov (United States)

Astrea, Guja; Battini, Roberta; Lenzi, Sara; Frosini, Silvia; Bonetti, Silvia; Moretti, Elena; Perazza, Silvia; Santorelli, Filippo M; Pecini, Chiara

2016-10-01

Although the presence of cognitive deficits in Duchenne muscular dystrophy or myotonic dystrophy DM1 is well established in view of brain-specific expression of affected muscle proteins, in other neuromuscular disorders, such as congenital myopathies and limb-girdle muscular dystrophies, cognitive profiles are poorly defined. Also, there are limited characterization of the cognitive profile of children with congenital muscular dystrophies, notwithstanding the presence of cerebral abnormality in some forms, and in spinal muscular atrophies, with the exception of distal spinal muscular atrophy (such as the DYN1CH1- associated form). Starting from the Duchenne muscular dystrophy, which may be considered a kind of paradigm for the co-occurrence of learning disabilities in the contest of a progressive muscular involvement, the findings of neuropsychological (or cognitive) dysfunctions in several forms of neuromuscular diseases will be examined and reviewed.

The effects of neuromuscular exercise on medial knee joint load post-arthroscopic partial medial meniscectomy: ‘SCOPEX’ a randomised control trial protocol

Science.gov (United States)

2012-01-01

Background Meniscectomy is a risk factor for knee osteoarthritis, with increased medial joint loading a likely contributor to the development and progression of knee osteoarthritis in this group. Therefore, post-surgical rehabilitation or interventions that reduce medial knee joint loading have the potential to reduce the risk of developing or progressing osteoarthritis. The primary purpose of this randomised, assessor-blind controlled trial is to determine the effects of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee joint load during functional tasks in people who have recently undergone a partial medial meniscectomy. Methods/design 62 people aged 30–50 years who have undergone an arthroscopic partial medial meniscectomy within the previous 3 to 12 months will be recruited and randomly assigned to a neuromuscular exercise or control group using concealed allocation. The neuromuscular exercise group will attend 8 supervised exercise sessions with a physiotherapist and will perform 6 exercises at home, at least 3 times per week for 12 weeks. The control group will not receive the neuromuscular training program. Blinded assessment will be performed at baseline and immediately following the 12-week intervention. The primary outcomes are change in the peak external knee adduction moment measured by 3-dimensional analysis during normal paced walking and one-leg rise. Secondary outcomes include the change in peak external knee adduction moment during fast pace walking and one-leg hop and change in the knee adduction moment impulse during walking, one-leg rise and one-leg hop, knee and hip muscle strength, electromyographic muscle activation patterns, objective measures of physical function, as well as self-reported measures of physical function and symptoms and additional biomechanical parameters. Discussion The findings from this trial will provide evidence regarding the effect of a home-based, physiotherapist

The effects of neuromuscular exercise on medial knee joint load post-arthroscopic partial medial meniscectomy: ‘SCOPEX’ a randomised control trial protocol

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Hall Michelle

2012-11-01

Full Text Available Abstract Background Meniscectomy is a risk factor for knee osteoarthritis, with increased medial joint loading a likely contributor to the development and progression of knee osteoarthritis in this group. Therefore, post-surgical rehabilitation or interventions that reduce medial knee joint loading have the potential to reduce the risk of developing or progressing osteoarthritis. The primary purpose of this randomised, assessor-blind controlled trial is to determine the effects of a home-based, physiotherapist-supervised neuromuscular exercise program on medial knee joint load during functional tasks in people who have recently undergone a partial medial meniscectomy. Methods/design 62 people aged 30–50 years who have undergone an arthroscopic partial medial meniscectomy within the previous 3 to 12 months will be recruited and randomly assigned to a neuromuscular exercise or control group using concealed allocation. The neuromuscular exercise group will attend 8 supervised exercise sessions with a physiotherapist and will perform 6 exercises at home, at least 3 times per week for 12 weeks. The control group will not receive the neuromuscular training program. Blinded assessment will be performed at baseline and immediately following the 12-week intervention. The primary outcomes are change in the peak external knee adduction moment measured by 3-dimensional analysis during normal paced walking and one-leg rise. Secondary outcomes include the change in peak external knee adduction moment during fast pace walking and one-leg hop and change in the knee adduction moment impulse during walking, one-leg rise and one-leg hop, knee and hip muscle strength, electromyographic muscle activation patterns, objective measures of physical function, as well as self-reported measures of physical function and symptoms and additional biomechanical parameters. Discussion The findings from this trial will provide evidence regarding the effect of a home

Does perioperative tactile evaluation of the train-of-four response influence the frequency of postoperative residual neuromuscular blockade?

DEFF Research Database (Denmark)

Pedersen, T; Viby-Mogensen, J; Bang, U

1990-01-01

pancuronium), the anesthetists assessed the degree of neuromuscular blockade during operation and during recovery from neuromuscular blockade by manual evaluation of the response to TOF nerve stimulation. In the other two groups, one of which received vecuronium and the other pancuronium, the anesthetists...... evaluated the degree of neuromuscular blockade solely by clinical criteria. The use of a nerve stimulator was found to have no effect on the dose of relaxant given during anesthesia, on the need for supplementary doses of anticholinesterase in the recovery room, on the time from end of surgery to end...... of anesthesia, or on the incidence of postoperative residual neuromuscular blockade evaluated clinically. The median (and range of) TOF ratios recorded in the recovery room were 0.75 (0.33-0.96) and 0.79 (0.10-0.97) in the vecuronium groups monitored with and without a nerve stimulator, respectively...

Biochemistry of Neuromuscular Diseases: A Course for Undergraduate Students

Science.gov (United States)

Ohlendieck, Kay

2002-01-01

This article outlines an undergraduate course focusing on supramolecular membrane protein complexes involved in the molecular pathogenesis of neuromuscular disorders. The emphasis of this course is to introduce students to the key elements involved in the ion regulation and membrane stabilization during muscle contraction and the role of these…

C-terminal agrin fragment is inversely related to neuromuscular fatigue in older men.

Science.gov (United States)

Stout, Jeffrey R; Fragala, Maren S; Hoffman, Jay R; Robinson, Edward H; Mccormack, William P; Townsend, Jeremy R; Jatjner, Adam R; Emerson, Nadia S; Oliveira, Leonardo P; Fukuda, David H

2015-01-01

The aim of this study was to examine the relationship between serum C-terminal agrin fragment (CAF) concentrations and neuromuscular fatigue in older adults. Twenty-two healthy older men and women volunteered for this study. Resting fasted blood samples were collected and prepared for measurement of serum CAF concentration by a commercially available ELISA kit. The onset of neuromuscular fatigue was measured by monitoring electromyographic fatigue curves from the vastus lateralis muscle using the physical working capacity at fatigue threshold (PWCFT ) test. A significant inverse correlation for men was observed between CAF and PWCFT (r = -0.602; P = 0.05), but not for women (r = 0.208; P = 0.54). After controlling for age and body mass index, significant correlations (r = -0.69; P = 0.042) remained for men, but not for women (r = 0.12; P = 0.76). These data suggest that serum CAF concentrations were significantly related to the onset of neuromuscular fatigue independent of age and BMI in men only. © 2014 Wiley Periodicals, Inc.

Neuromuscular activity during bench press exercise performed with and without the preexhaustion method.

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Brennecke, Allan; Guimarães, Thiago M; Leone, Ricardo; Cadarci, Mauro; Mochizuki, Luiz; Simão, Roberto; Amadio, Alberto Carlos; Serrão, Júlio C

2009-10-01

The purpose of the present study was to investigate the effects of exercise order on the tonic and phasic characteristics of upper-body muscle activity during bench press exercise in trained subjects. The preexhaustion method involves working a muscle or a muscle group combining a single-joint exercise immediately followed by a multi-joint exercise (e.g., flying exercise followed by bench press exercise). Twelve subjects performed 1 set of bench press exercises with and without the preexhaustion method following 2 protocols (P1-flying before bench press; P2-bench press). Both exercises were performed at a load of 10 repetition maximum (10RM). Electromyography (EMG) sampled at 1 kHz was recorded from the pectoralis major (PM), anterior deltoid (DA), and triceps brachii (TB). Kinematic data (60 Hz) were synchronized to define upward and downward phases of exercise. No significant (p > 0.05) changes were seen in tonic control of PM and DA muscles between P1 and P2. However, TB tonic aspect of neurophysiologic behavior of motor units was significantly higher (p 0.05). The kinematic pattern of movement changed as a result of muscular weakness in P1. Angular velocity of the right shoulder performed during the upward phase of the bench press exercise was significantly slower (p < 0.05) during P1. Our results suggest that the strategies set by the central nervous system to provide the performance required by the exercise are held constant throughout the exercise, but the tonic aspects of the central drive are increased so as to adapt to the progressive occurrence of the neuromuscular fatigue. Changes in tonic control as a result of the muscular weakness and fatigue can cause changes in movement techniques. These changes may be related to limited ability to control mechanical loads and mechanical energy transmission to joints and passive structures.

Neuromuscular Control of Rapid Linear Accelerations in Fish

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2016-06-22

sunfish, Lepomis macrochirus. Animals with flexible bodies, like fishes , face a tradeoff for rapid movements. To produce high forces, they must...2014 30-Apr-2015 Approved for Public Release; Distribution Unlimited Final Report: Neuromuscular Control of Rapid Linear Accelerations in Fish The...Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 swimming, acceleration, fish , muscle, stiffness REPORT DOCUMENTATION PAGE 11. SPONSOR

Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

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Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2014-10-01

Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity.

Relationship between skin temperature and muscle activation during incremental cycle exercise.

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Priego Quesada, Jose I; Carpes, Felipe P; Bini, Rodrigo R; Salvador Palmer, Rosario; Pérez-Soriano, Pedro; Cibrián Ortiz de Anda, Rosa M

2015-02-01

While different studies showed that better fitness level adds to the efficiency of the thermoregulatory system, the relationship between muscular effort and skin temperature is still unknown. Therefore, the present study assessed the relationship between neuromuscular activation and skin temperature during cycle exercise. Ten physically active participants performed an incremental workload cycling test to exhaustion while neuromuscular activations were recorded (via surface electromyography - EMG) from rectus femoris, vastus lateralis, biceps femoris and gastrocnemius medialis. Thermographic images were recorded before, immediately after and 10 min after finishing the cycling test, at four body regions of interest corresponding to the muscles where neuromuscular activations were monitored. Frequency band analysis was conducted to assess spectral properties of EMG signals in order to infer on priority in recruitment of motor units. Significant inverse relationship between changes in skin temperature and changes in overall neuromuscular activation for vastus lateralis was observed (r0.7 and p<0.01). Participants with larger overall activation and reduced low frequency component for vastus lateralis activation presented a better adaptive response of their thermoregulatory system by showing fewer changes in skin temperature after incremental cycling test. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sugammadex to reverse neuromuscular blockade and provide optimal conditions for motor-evoked potential monitoring

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Mehdi Trifa

2017-01-01

Full Text Available Sugammadex is a novel pharmacologic agent, which reverses neuromuscular blockade (NMB via a mechanism that differs completely from acetylcholinesterase inhibitors. By encapsulating rocuronium, sugammadex can provide recovery of neuromuscular function even when there is a profound degree of NMB. We report anecdotal experience with the use of sugammadex to reverse NMB to facilitate intraoperative neurophysiological monitoring (motor evoked potentials in an adolescent with scoliosis during posterior spinal fusion. Its potential application in this unique clinical scenario is discussed, and potential dosing schemes are reviewed.

Effect of Dex medetomidine on Neuromuscular Blockade in Patients Undergoing Complex Major Abdominal or Pelvic Surgery

International Nuclear Information System (INIS)

El-Awady, G.A.; Abdelhalim, J.M.K.; Azer, M.S.

2003-01-01

Dex medetomidine is a highly selective α2 agonist with anesthetic, analgesic and sympatholytic properties. Its neuromuscular effects in humans are unknown. This study evaluates the effect of dex medetomidine on neuromuscular block and hemodynamics during thiopental/ isoflurane anesthesia for patients with complex abdominal or pelvic surgery. Patients and methods: During thiopental/isoflurane anesthesia, the rocuronium infusion rate was adjusted in 20 complex surgery patients to maintain a stable first response (T1) in the train of four sequence of 50% ± 3 of the pre-rocuronium value. Dex medetomidine was then administered by infusion pump, targeting a plasma dex medetomidine concentration of 0.6 ng/dL for 45 min. The evoked mechanical responses of the adductor pollicis responses (T1 response and T4/T1 ratio), systolic blood pressure, diastolic blood pressure and heart rate (HR) were measured during the dex medetomidine infusion using repeated measures analysis of variance. Plasma levels ranged from 0.73 to 1.38 ng/mL. Results: T1 values decreased during the infusion from 55(ρ2 to 38±9 ((ρ< 0.05). T4/Tl values did not change during the infusion. Dex medetomidine increased SBP (ρ< 0.001) and decreased HR ((ρ< 0.05) (10 min median values) during the infusion compared with values before the infusion. This study demonstrated that dex medetomidine decreased T1, increased SBP and decreased HR during thiopental/isoflurane anesthesia. Conclusion: We conclude that dex medetomidine induced direct vasoconstriction may alter pharmacokinetics of rocuronium, therefore increasing plasma rocuronium concentration. Although these effects were statistically significant, further studies should be held for understanding and characterizing the peripheral vasoconstrictive effects of a2 agonists that allow better management and determination of drug dosing regimens

Effects of transcranial direct current stimulation of the motor cortex on prefrontal cortex activation during a neuromuscular fatigue task: an fNIRS study.

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Muthalib, Makii; Kan, Benjamin; Nosaka, Kazunori; Perrey, Stephane

2013-01-01

This study investigated whether manipulation of motor cortex excitability by transcranial direct current stimulation (tDCS) modulates neuromuscular fatigue and functional near-infrared spectroscopy (fNIRS)-derived prefrontal cortex (PFC) activation. Fifteen healthy men (27.7 ± 8.4 years) underwent anodal (2 mA, 10 min) and sham (2 mA, first 30 s only) tDCS delivered to the scalp over the right motor cortex. Subjects initially performed a baseline sustained submaximal (30 % maximal voluntary isometric contraction, MVC) isometric contraction task (SSIT) of the left elbow flexors until task failure, which was followed 50 min later by either an anodal or sham treatment condition, then a subsequent posttreatment SSIT. Endurance time (ET), torque integral (TI), and fNIRS-derived contralateral PFC oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin concentration changes were determined at task failure. Results indicated that during the baseline and posttreatment SSIT, there were no significant differences in TI and ET, and increases in fNIRS-derived PFC activation at task failure were observed similarly regardless of the tDCS conditions. This suggests that the PFC neuronal activation to maintain muscle force production was not modulated by anodal tDCS.

Influência da procainamida sobre o bloqueio neuromuscular produzido pelo rocurônio e investigação sobre o mecanismo de ação da procainamida na junção neuromuscular Influencia de la procainamida sobre el bloqueo neuromuscular producido por el rocuronio e investigación sobre el mecanismo de acción de la procainamida en la junción neuromuscular Influence of procainamide on the neuromuscular blockade caused by rocuronium and investigation on the mechanism of action of procainamide on the neuromuscular junction

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Thalita Duque Martins

2007-02-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: A potencialização da procainamida sobre o bloqueio neuromuscular produzido pela d-tubocurarina já está comprovada, porém o mecanismo é controverso. O objetivo do estudo foi avaliar a influência da procainamida no bloqueio neuromuscular produzido pelo rocurônio e investigar os mecanismos desta interação. MÉTODO: Foram utilizados 15 ratos (250 a 300 g em preparação descrita por Bülbring. Formaram-se os seguintes grupos (n = 5 cada: procainamida - 20 µg.mL-1 (Grupo I; rocurônio - 4 µg.mL-1 (Grupo II e rocurônio - 4 µg.mL-1 e procainamida - 20 µg.mL-1 (Grupo III. Avaliaram-se: 1 a amplitude das contrações musculares sob estimulação indireta em cada grupo, antes e após a adição dos fármacos; 2 os potenciais de placa terminal em miniatura (PPTM; 3 a eficácia da 4-aminopiridina na reversão do bloqueio neuromuscular. O mecanismo da interação foi estudado em Biventer cervicis (n = 5 e diafragma de rato desnervado (n = 5, observando-se a influência da procainamida na resposta à acetilcolina antes e após a adição da procainamida. RESULTADOS: A procainamida isoladamente não alterou as respostas neuromusculares. O bloqueio produzido com o Grupo III foi de 68,6% ± 7,1%, com diferença significativa (p = 0,0067 em relação ao Grupo II (10,4% ± 4,5%, revertido pela 4-aminopiridina. A procainamida ocasionou aumento na freqüência dos PPTM, seguido de bloqueio revertido pela 4-aminopiridina. Em Biventer cervicis a procainamida aumentou a resposta à ação de contração da acetilcolina, resultado não observado com o diafragma desnervado. CONCLUSÕES: A procainamida potencializou o bloqueio produzido pelo rocurônio. As alterações observadas com PPTM e Biventer cervicis identificaram ação pré-sináptica. O antagonismo da 4-aminopiridina sobre o bloqueio dos PPTM sugeriu dessensibilização dos receptores pela procainamida.JUSTIFICATIVA Y OBJETIVOS: La potenciación de la procainamida sobre

Emerging modalities in dysphagia rehabilitation: neuromuscular electrical stimulation.

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Huckabee, Maggie-Lee; Doeltgen, Sebastian

2007-10-12

The aim of this review article is to advise the New Zealand medical community about the application of neuromuscular electrical stimulation (NMES) as a treatment for pharyngeal swallowing impairment (dysphagia). NMES in this field of rehabilitation medicine has quickly emerged as a widely used method overseas but has been accompanied by significant controversy. Basic information is provided about the physiologic background of electrical stimulation. The literature reviewed in this manuscript was derived through a computer-assisted search using the biomedical database Medline to identify all relevant articles published until from the initiation of the databases up to January 2007. The reviewers used the following search strategy: [(deglutition disorders OR dysphagia) AND (neuromuscular electrical stimulation OR NMES)]. In addition, the technique of reference tracing was used and very recently published studies known to the authors but not yet included in the database systems were included. This review elucidates not only the substantive potential benefit of this treatment, but also potential key concerns for patient safety and long term outcome. The discussion within the clinical and research communities, especially around the commercially available VitalStim stimulator, is objectively explained.

The use of an online support group for neuromuscular disorders: a thematic analysis of message postings.

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Meade, Oonagh; Buchanan, Heather; Coulson, Neil

2017-06-08

People affected by neuromuscular disorders can experience adverse psychosocial consequences and difficulties accessing information and support. Online support groups provide new opportunities for peer support. The aim of this study was to understand how contributors used the message board function of a newly available neuromuscular disorders online support group. Message postings (n = 1951) from the first five months of the message board of a newly formed online support group for neuromuscular disorders hosted by a charitable organization were analyzed using inductive thematic analysis. Members created a sense of community through disclosing personal information, connecting with people with similar illness experiences or interests, welcoming others and sharing aspirations for the development of a resourceful community. Experiences, emotional reactions and support were shared in relation to: delayed diagnosis; symptom interpretation; illness management and progression; the isolating impact of rare disorders; and the influence of social and political factors on illness experiences. This study provided a novel insight into individuals' experiences of accessing a newly available online support group for rare conditions hosted by a charitable organization. The findings highlight how the online support group provided an important peer support environment for members to connect with others, exchange information and support and engender discussion on political and social issues unique to living with often-rare neuromuscular disorders. Online support groups may therefore provide an important and easily accessible support outlet for people with neuromuscular disorders as well as a platform for empowering members to raise awareness about the impact of living with these conditions. Further research is needed to examine member motivations for using such groups and any effects of participation in greater detail. Implications for rehabilitation Online support groups may

Effect of a neuromuscular training program on the kinetics and kinematics of jumping tasks.

Science.gov (United States)

Chappell, Jonathan D; Limpisvasti, Orr

2008-06-01

Altered motor control strategies are a proposed cause of the female athlete's increased risk for noncontact anterior cruciate ligament injury. Injury prevention programs have shown promising results in decreasing the incidence of anterior cruciate ligament injury. To evaluate the effect of the Kerlan-Jobe Orthopaedic Clinic Modified Neuromuscular Training Program on the biomechanics of select jumping tasks in the female collegiate athlete. Controlled laboratory study. Thirty female National Collegiate Athletic Association Division I soccer and basketball players performed vertical jump, hopping tests, and 2 jumping tasks (drop jump and stop jump). All subjects completed a 6-week neuromuscular training program with core strengthening and plyometric training. Three-dimensional motion analysis and force plate data were used to compare the kinetics and kinematics of jumping tasks before and after training. Dynamic knee valgus moment during the stance phase of stop jump tasks decreased after completion of the neuromuscular training program (P = .04), but differences were not observed for the drop jump. Initial knee flexion (P = .003) and maximum knee flexion (P = .006) angles increased during the stance phase of drop jumps after training, but differences were not observed for the stop jump. The athletes showed improved performance in vertical jump (P training program improved select athletic performance measures and changed movement patterns during jumping tasks in the subject population. The use of this neuromuscular training program could potentially modify the collegiate athlete's motion strategies, improve performance, and lower the athlete's risk for injury.

Isometric and dynamic strength and neuromuscular attributes as predictors of vertical jump performance in 11- to 13-year-old male athletes.

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McKinlay, Brandon John; Wallace, Phillip J; Dotan, Raffy; Long, Devon; Tokuno, Craig; Gabriel, David A; Falk, Bareket

2017-09-01

In explosive contractions, neural activation is a major factor in determining the rate of torque development, while the latter is an important determinant of jump performance. However, the contribution of neuromuscular activation and rate of torque development to jump performance in children and youth is unclear. The purpose of this study was to examine the relationships between the rate of neuromuscular activation, peak torque, rate of torque development, and jump performance in young male athletes. Forty-one 12.5 ± 0.5-year-old male soccer players completed explosive, unilateral isometric and dynamic (240°/s) knee extensions (Biodex System III), as well as countermovement-, squat-, and drop-jumps. Peak torque (pT), peak rate of torque development (pRTD), and rate of vastus lateralis activation (Q 30 ) during the isometric and dynamic contractions were examined in relation to attained jump heights. Isometric pT and pRTD were strongly correlated (r = 0.71) but not related to jump performance. Dynamic pT and pRTD, normalized to body mass, were significantly related to jump height in all 3 jumps (r = 0.38-0.66, p jump performance, while isometric contractions are not. These findings have implications in the choice of training and assessment methods for young athletes.

A Versatile Active Block: DXCCCII and Tunable Applications

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S. A. Tekin

2014-12-01

Full Text Available The study describes dual-X controlled current conveyor (DXCCCII as a versatile active block and its application to inductance simulators for testing. Moreover, the high pass filter application using with DXCCCII based inductance simulator and oscillator with flexible tunable oscillation frequency have been presented and simulated to confirm the theoretical validity. The proposed circuit which has a simple circuit design requires the low-voltage and the DXCCCII can also be tuned in the wide range by the biasing current. The proposed DXCCCII provides a good linearity, high output impedance at Z terminals, and a reasonable current and voltage transfer gain accuracy. The proposed DXCCCII and its applications have been simulated using the CMOS 0.18 µm technology.

Neuromuscular electrical stimulation improves exercise tolerance in chronic obstructive pulmonary disease patients with better preserved fat-free mass

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Lara Maris Nápolis

2011-01-01

Full Text Available BACKGROUND: High-frequency neuromuscular electrical stimulation increases exercise tolerance in patients with advanced chronic obstructive pulmonary disease (COPD patients. However, it is conceivable that its benefits are more prominent in patients with better-preserved peripheral muscle function and structure. OBJECTIVE: To investigate the effects of high-frequency neuromuscular electrical stimulation in COPD patients with better-preserved peripheral muscle function. Design: Prospective and cross-over study. METHODS: Thirty COPD patients were randomly assigned to either home-based, high-frequency neuromuscular electrical stimulation or sham stimulation for six weeks. The training intensity was adjusted according to each subject's tolerance. Fat-free mass, isometric strength, six-minute walking distance and time to exercise intolerance (Tlim were assessed. RESULTS: Thirteen (46.4% patients responded to high-frequency neuromuscular electrical stimulation; that is, they had a post/pre Δ Tlim >10% after stimulation (unimproved after sham stimulation. Responders had a higher baseline fat-free mass and six-minute walking distance than their seventeen (53.6% non-responding counterparts. Responders trained at higher stimulation intensities; their mean amplitude of stimulation during training was significantly related to their fat-free mass (r = 0.65; p<0.01. Logistic regression revealed that fat-free mass was the single independent predictor of Tlim improvement (odds ratio [95% CI] = 1.15 [1.04-1.26]; p<0.05. CONCLUSIONS: We conclude that high-frequency neuromuscular electrical stimulation improved the exercise capacity of COPD patients with better-preserved fat-free mass because they tolerated higher training stimulus levels. These data suggest that early training with high-frequency neuromuscular electrical stimulation before tissue wasting begins might enhance exercise tolerance in patients with less advanced COPD.

Thermo-responsive, UV-active poly(phenyl acrylate-b-poly(diethyl acrylamide block copolymers

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M. Maric

2013-12-01

Full Text Available The homopolymerization of phenyl acrylate (PA was investigated for the first time by nitroxide mediated polymerization (NMP with the succinimidyl form of the SG1-based unimolecular initiator 2-[N-tert-butyl-2,2-(dimethylpropyl-aminooxy]propionic acid (BlocBuilder MA. The control of PPA homopolymerization was improved by the use of 15 mol% additional free nitroxide SG1 ([tert-butyl[1-(diethoxyphosphoryl-2,2-dimethylpropyl]amino]oxidanyl and dispersities, Mw/Mn, of around 1.2 were achieved. A PPA homopolymer was then successfully chain-extended with diethyl acrylamide (DEAAm to form a block copolymer of PPA-b-PDEAAm where the PDEAAm segment is thermo-responsive, while the PPA block is potentially UV-active. The thermo-responsive behavior of the block copolymer in 0.5 wt% aqueous solution was studied by UV-Vis spectrometry and dynamic light scattering (DLS, indicating cloud point temperatures of 26–30°C, close to that reported for PDEAAm homopolymers.

Transmitter release in the neuromuscular synapse of the protein kinase C theta-deficient adult mouse.

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Besalduch, Núria; Santafé, Manel M; Garcia, Neus; Gonzalez, Carmen; Tomás, Marta; Tomás, Josep; Lanuza, Maria A

2011-04-01

We studied structural and functional features of the neuromuscular junction in adult mice (P30) genetically deficient in the protein kinase C (PKC) theta isoform. Confocal and electron microscopy shows that there are no differences in the general morphology of the endplates between PKC theta-deficient and wild-type (WT) mice. Specifically, there is no difference in the density of the synaptic vesicles. However, the myelin sheath is not as thick in the intramuscular nerve fibers of the PKC theta-deficient mice. We found a significant reduction in the size of evoked endplate potentials and in the frequency of spontaneous, asynchronous, miniature endplate potentials in the PKC theta-deficient neuromuscular preparations in comparison with the WT, but the mean amplitude of the spontaneous potentials is not different. These changes indicate that PKC theta has a presynaptic role in the function of adult neuromuscular synapses. Copyright © 2010 Wiley-Liss, Inc.

Recommendations on the use of deep neuromuscular blockade by anaesthesiologists and surgeons. AQUILES (Anestesia QUIrúrgica para Lograr Eficiencia y Seguridad) Consensus.

Science.gov (United States)

Errando-Oyonarte, C L; Moreno-Sanz, C; Vila-Caral, P; Ruiz de Adana-Belbel, J C; Vázquez-Alonso, E; Ramírez-Rodríguez, J M; Veiga-Ruiz, G; Guasch-Arévalo, E; Lora-Tamayo D'Ocón, J I

2017-02-01

Neuromuscular blockade enables airway management, ventilation and surgical procedures. However there is no national consensus on its routine clinical use. The objective was to establish the degree of agreement among anaesthesiologists and general surgeons on the clinical use of neuromuscular blockade in order to make recommendations to improve its use during surgical procedures. Multidisciplinary consensus study in Spain. Anaesthesiologists experts in neuromuscular blockade management (n=65) and general surgeons (n=36) were included. Delphi methodology was selected. A survey with 17 final questions developed by a dedicated scientific committee was designed. The experts answered the successive questions in two waves. The survey included questions on: type of surgery, type of patient, benefits/harm during and after surgery, impact of objective neuromuscular monitoring and use of reversal drugs, viability of a multidisciplinary and efficient approach to the whole surgical procedure, focussing on the level of neuromuscular blockade. Five recommendations were agreed: 1) deep neuromuscular blockade is very appropriate for abdominal surgery (degree of agreement 94.1%), 2) and in obese patients (76.2%); 3) deep neuromuscular blockade maintenance until end of surgery might be beneficial in terms of clinical aspects, such as as immobility or better surgical access (86.1 to 72.3%); 4) quantitative monitoring and reversal drugs availability is recommended (89.1%); finally 5) anaesthesiologists/surgeons joint protocols are recommended. Collaboration among anaesthesiologists and surgeons has enabled some general recommendations to be established on deep neuromuscular blockade use during abdominal surgery. Copyright © 2016 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

Comparison of reversal with neostigmine of low-dose rocuronium vs. reversal with sugammadex of high-dose rocuronium for a short procedure.

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Choi, E S; Oh, A Y; Koo, B W; Hwang, J W; Han, J W; Seo, K S; Ahn, S H; Jeong, W J

2017-10-01

Some short procedures require deep neuromuscular blockade, which needs to be reversed at the end of the procedure. Forty-four patients undergoing elective laryngeal micro-surgery were randomly allocated into two groups: rocuronium 0.45 mg.kg -1 with neostigmine (50 μg.kg -1 with glycopyrrolate 10 μg.kg -1 ) reversal (moderate block group) vs. rocuronium 0.90 mg.kg -1 with sugammadex (4 mg.kg -1 ) reversal (deep block group). The primary outcome was the intubating conditions during laryngoscopy secondary outcomes included recovery of neuromuscular block; conditions for tracheal intubation; satisfaction score as determined by the surgeon; onset of neuromuscular block; and postoperative sore throat. The onset of neuromuscular block was more rapid, and intubation conditions and ease of intra-operative laryngoscopy were more favourable, and the satisfaction score was lower in the moderate block group compared with the deep block group. No difference was found in the incidence of postoperative sore throat. In laryngeal micro-surgery, the use of rocuronium 0.9 mg.kg -1 with sugammadex for reversal was associated with better surgical conditions and a shorter recovery time than rocuronium 0.45 mg.kg -1 with neostigmine. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

Minimally Invasive Scoliosis Surgery: A Novel Technique in Patients with Neuromuscular Scoliosis

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Vishal Sarwahi

2015-01-01

Full Text Available Minimally invasive surgery (MIS has been described in the treatment of adolescent idiopathic scoliosis (AIS and adult scoliosis. The advantages of this approach include less blood loss, shorter hospital stay, earlier mobilization, less tissue disruption, and relatively less pain. However, despite these significant benefits, MIS approach has not been reported in neuromuscular scoliosis patients. This is possibly due to concerns with longer surgery time, which is further increased due to more levels fused and instrumented, challenges of pelvic fixation, size and number of incisions, and prolonged anesthesia. We modified the MIS approach utilized in our AIS patients to be implemented in our neuromuscular patients. Our technique allows easy passage of contoured rods, placement of pedicle screws without image guidance, partial/complete facet resection, and all standard reduction maneuvers. Operative time needed to complete this surgery is comparable to the standard procedure and the majority of our patients have been extubated at the end of procedure, spending 1 day in the PICU and 5-6 days in the hospital. We feel that MIS is not only a feasible but also a superior option in patients with neuromuscular scoliosis. Long-term results are unavailable; however, short-term results have shown multiple benefits of this approach and fewer limitations.

Small molecule inhibitors block Gas6-inducible TAM activation and tumorigenicity.

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Kimani, Stanley G; Kumar, Sushil; Bansal, Nitu; Singh, Kamalendra; Kholodovych, Vladyslav; Comollo, Thomas; Peng, Youyi; Kotenko, Sergei V; Sarafianos, Stefan G; Bertino, Joseph R; Welsh, William J; Birge, Raymond B

2017-03-08

TAM receptors (Tyro-3, Axl, and Mertk) are a family of three homologous type I receptor tyrosine kinases that are implicated in several human malignancies. Overexpression of TAMs and their major ligand Growth arrest-specific factor 6 (Gas6) is associated with more aggressive staging of cancers, poorer predicted patient survival, acquired drug resistance and metastasis. Here we describe small molecule inhibitors (RU-301 and RU-302) that target the extracellular domain of Axl at the interface of the Ig-1 ectodomain of Axl and the Lg-1 of Gas6. These inhibitors effectively block Gas6-inducible Axl receptor activation with low micromolar IC 50s in cell-based reporter assays, inhibit Gas6-inducible motility in Axl-expressing cell lines, and suppress H1299 lung cancer tumor growth in a mouse xenograft NOD-SCIDγ model. Furthermore, using homology models and biochemical verifications, we show that RU301 and 302 also inhibit Gas6 inducible activation of Mertk and Tyro3 suggesting they can act as pan-TAM inhibitors that block the interface between the TAM Ig1 ectodomain and the Gas6 Lg domain. Together, these observations establish that small molecules that bind to the interface between TAM Ig1 domain and Gas6 Lg1 domain can inhibit TAM activation, and support the further development of small molecule Gas6-TAM interaction inhibitors as a novel class of cancer therapeutics.

Quality of life after surgery for neuromuscular scoliosis

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Peter Obid

2013-02-01

Full Text Available Surgery in patients with neuromuscular scoliosis is associated with a higher rate of complications. It is still controversially discussed whether the patients truly benefit from deformity correction. The purpose of this study is to investigate if the quality of life has been improved and if the patients and their caregivers are satisfied with the results of surgery. This is a retrospective clinical outcome study of 46 patients with neuromuscular scoliosis which were treated with primary stable posterior pedicle screw instrumentation and correction. To achieve fusion only autologous bone was used. Follow up was minimum 2 years and maximum 5 years with an average of 36 months. The patients and/or their caregivers received a questionnaire based on the PEDI (pediatric disability inventory and the GMFS (gross motor function score. The patients (and their caregivers were also asked if the quality of life has improved after surgery. Only 32 of 46 patients answered the questionnaire. The answers showed a high approval-rate regarding the patients satisfaction with the surgery and the improvement of quality of life. The questionnaire could be answered from 1 (I do not agree to 4 (I completely agree. The average agreement to the following statements was: i the quality of life has improved: 3.35; ii I am satisfied with surgery: 3.95; iii the operation has fulfilled my expectations: 3.76. The average age at surgery was 12.7 years. The mean pre-operative cobb-angle of the main curve was 83.1° with a correction post-operatively to a mean of 36.9° and 42.6° at final follow-up. That is an average correction of 56.9%. Although spinal fusion in neuromuscular scoliosis is associated with a higher rate of complications our results show that the patients and their caregivers are satisfied with the operation and the quality of life has improved after surgery.

Neuromuscular diseases: Diagnosis and management.

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Mary, P; Servais, L; Vialle, R

2018-02-01

Neuromuscular diseases (NMDs) affect the peripheral nervous system, which includes the motor neurons and sensory neurons; the muscle itself; or the neuromuscular junction. Thus, the term NMDs encompasses a vast array of different syndromes. Some of these syndromes are of direct relevance to paediatric orthopaedic surgeons, either because the presenting manifestation is a functional sign (e.g., toe-walking) or deformity (e.g., pes cavus or scoliosis) suggesting a need for orthopaedic attention or because orthopaedic abnormalities requiring treatment develop during the course of a known NMD. The main NMDs relevant to the orthopaedic surgeon are infantile spinal muscular atrophy (a motor neuron disease), peripheral neuropathies (chiefly, Charcot-Marie-Tooth disease), congenital muscular dystrophies, progressive muscular dystrophies, and Steinert myotonic dystrophy (or myotonic dystrophy type 1). Muscle weakness is a symptom shared by all these conditions. The paediatric orthopaedic surgeon must be familiar, not only with the musculoskeletal system, but also with many other domains (particularly respiratory and cardiac function and nutrition) that may interfere with the treatment and require preoperative management. Good knowledge of the natural history of each NMD is essential to ensure optimal timing of the therapeutic interventions, which must be performed under the best possible conditions in these usually frail patients. Timing is particularly crucial for the treatment of spinal deformities due to paraspinal muscle hypotonia during growth: depending on the disease and natural history, the treatment may involve non-operative methods or growing rods, followed by spinal fusion. A multidisciplinary approach is always required. Finally, the survival gains achieved in recent years increasingly require attention to preparing for adult life, to orthopaedic problems requiring treatment before the patient leaves the paediatric environment, and to the transition towards the

Acute effects of the use of external instability generating devices on neuromuscular performance

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Guillermo Peña García-Orea

2016-02-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n6p722   Physical training with the use of instability generator devices has become popular in the health area, in sport training and clinical practice (mainly in the prevention and treatment of injuries. To understand how the process of using these devices occurs and the results of their acute effects is important to guide professionals in choosing the appropriate device. The aim of this review was to present the main features of instability devices and analyze their acute effects on core muscle activation, neuromuscular performance and activation of lower and upper limbs. Studies have shown that the main acute effects of exercises performed with these devices are: 1 increased activation / muscular recruitment (especially in the middle zone or core; 2 greater co-activation of antagonist muscles (trunk, upper and lower limbs, with increased stiffness and joint stability; 3 lower force output, power and speed in extremities.

No Neuromuscular Side-Effects of Scopolamine in Sensorimotor Control and Force-Generating Capacity Among Parabolic Fliers

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Ritzmann, Ramona; Freyler, Kathrin; Krause, Anne; Gollhofer, Albert

2016-10-01

Scopolamine is used to counteract motion sickness in parabolic flight (PF) experiments. Although the drug's anticholinergic properties effectively impede vomiting, recent studies document other sensory side-effects in the central nervous system that may considerably influence sensorimotor performance. This study aimed to quantify such effects in order to determine if they are of methodological and operational significance for sensorimotor control. Ten subjects of a PF campaign received a weight-sex-based dose of a subcutaneous scopolamine injection. Sensorimotor performance was recorded before medication, 20min, 2h and 4h after injection in four space-relevant paradigms: balance control in one-leg stance with eyes open (protocol 1) and closed as well as force-generating capacity in countermovement jumps and hops (protocol 2). Postural sway, forces and joint angles were recorded. Neuromuscular control was assessed by electromyography and peripheral nerve stimulation; H-reflexes and M-waves were used to monitor spinal excitability of the Ia afferent reflex circuitry and maximal motor output. (1) H-reflex amplitudes, latencies and functional reflexes remained unchanged after scopolamine injection. (2) M-waves, neuromuscular activation intensities and antagonistic muscle coordination did not change with scopolamine administration. (3) Balance performance and force-generating capacity were not impeded by scopolamine. We found no evidence for changes in sensorimotor control in response to scopolamine injection. Sensory processing of daily relevant reflexes, spinal excitability, maximal motor output and performance parameters were not sensitive to the medication. We conclude that scopolamine administration can be used to counteract motion sickness in PF without methodological and operational concerns or interference regarding sensorimotor skills associated with neuromuscular control.

Generation of functional neuromuscular junctions from human pluripotent stem cell lines

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Katja ePuttonen

2015-12-01

Full Text Available Several neuromuscular diseases involve dysfunction of neuromuscular junctions (NMJs, yet there are no patient-specific human models for electrophysiological characterization of NMJ. We seeded cells of neurally-induced embryoid body-like spheres derived from induced pluripotent stem cell (iPSC or embryonic stem cell (ESC lines as monolayers without basic fibroblast factor (bFGF and observed differentiation of neuronal as well as spontaneously contracting, multinucleated skeletal myotubes. The myotubes showed striation, immunoreactivity for myosin heavy chain, actin bundles typical for myo-oriented cells, and generated spontaneous and evoked action potentials (APs. The myogenic differentiation was associated with expression of MyoD1, myogenin and type I ryanodine receptor. Neurons formed end plate like structures with strong binding of α-bungarotoxin, a marker of nicotinic acetylcholine receptors highly expressed in the postsynaptic membrane of NMJs, and expressed SMI-32, a motoneuron marker, as well as SV2, a marker for synapses. Pharmacological stimulation of cholinergic receptors resulted in strong depolarization of myotube membrane and raised Ca2+ concentration in sarcoplasm, while electrical stimulation evoked Ca2+ transients in myotubes. Stimulation of motoneurons with N-Methyl-D-aspartate resulted in reproducible APs in myotubes and end plates displayed typical MEPs and tonic activity depolarizing myotubes of about 10 mV. We conclude that simultaneous differentiation of neurons and myotubes from patient-specific iPSCs or ESCs results also in the development of functional NMJs. Our human model of NMJ may serve as an important tool to investigate normal development, mechanisms of diseases and novel drug targets involving NMJ dysfunction and degeneration.

Man-Machine Interface System for Neuromuscular Training and Evaluation Based on EMG and MMG Signals

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Patricia Fernández

2010-12-01

Full Text Available This paper presents the UVa-NTS (University of Valladolid Neuromuscular Training System, a multifunction and portable Neuromuscular Training System. The UVa-NTS is designed to analyze the voluntary control of severe neuromotor handicapped patients, their interactive response, and their adaptation to neuromuscular interface systems, such as neural prostheses or domotic applications. Thus, it is an excellent tool to evaluate the residual muscle capabilities in the handicapped. The UVa-NTS is composed of a custom signal conditioning front-end and a computer. The front-end electronics is described thoroughly as well as the overall features of the custom software implementation. The software system is composed of a set of graphical training tools and a processing core. The UVa-NTS works with two classes of neuromuscular signals: the classic myoelectric signals (MES and, as a novelty, the myomechanic signals (MMS. In order to evaluate the performance of the processing core, a complete analysis has been done to classify its efficiency and to check that it fulfils with the real-time constraints. Tests were performed both with healthy and selected impaired subjects. The adaptation was achieved rapidly, applying a predefined protocol for the UVa-NTS set of training tools. Fine voluntary control was demonstrated to be reached with the myoelectric signals. And the UVa-NTS demonstrated to provide a satisfactory voluntary control when applying the myomechanic signals.

Man-machine interface system for neuromuscular training and evaluation based on EMG and MMG signals.

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de la Rosa, Ramon; Alonso, Alonso; Carrera, Albano; Durán, Ramon; Fernández, Patricia

2010-01-01

This paper presents the UVa-NTS (University of Valladolid Neuromuscular Training System), a multifunction and portable Neuromuscular Training System. The UVa-NTS is designed to analyze the voluntary control of severe neuromotor handicapped patients, their interactive response, and their adaptation to neuromuscular interface systems, such as neural prostheses or domotic applications. Thus, it is an excellent tool to evaluate the residual muscle capabilities in the handicapped. The UVa-NTS is composed of a custom signal conditioning front-end and a computer. The front-end electronics is described thoroughly as well as the overall features of the custom software implementation. The software system is composed of a set of graphical training tools and a processing core. The UVa-NTS works with two classes of neuromuscular signals: the classic myoelectric signals (MES) and, as a novelty, the myomechanic signals (MMS). In order to evaluate the performance of the processing core, a complete analysis has been done to classify its efficiency and to check that it fulfils with the real-time constraints. Tests were performed both with healthy and selected impaired subjects. The adaptation was achieved rapidly, applying a predefined protocol for the UVa-NTS set of training tools. Fine voluntary control was demonstrated to be reached with the myoelectric signals. And the UVa-NTS demonstrated to provide a satisfactory voluntary control when applying the myomechanic signals.

Repetitive Daily Point of Choice Prompts and Occupational Sit-Stand Transfers, Concentration and Neuromuscular Performance in Office Workers: An RCT

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Lars Donath

2015-04-01

Full Text Available Objective: Prolonged office sitting time adversely affects neuromuscular and cardiovascular health parameters. As a consequence, the present study investigated the effects of prompting the use of height-adjustable working desk (HAWD on occupational sitting and standing time, neuromuscular outcomes and concentration in office workers. Methods: A single-blinded randomized controlled trial (RCT with parallel group design was conducted. Thirty-eight office workers were supplied with HAWDs and randomly assigned (Strata: physical activity (PA, BMI, gender, workload to a prompt (INT or non-prompt (CON group. INT received three daily screen-based prompts within 12 weeks. CON was only instructed once concerning the benefits of using HAWDs prior to the start of the study. Sitting and standing times were objectively assessed as primary outcomes for one entire working week using the ActiGraph wGT3X-BT at baseline (pre, after 6 (mid and 12 weeks (post. Concentration (d2-test, postural sway during upright stance (under single, dual and triple task and lower limb strength endurance (heel-rise were collected as secondary outcomes. Results: With large but not statistically significant within group effects from pre to post, INT increased weekly standing time at work by 9% (p = 0.22, d = 0.8 representing an increase from 7.2 h (4.8 to 9.7 (6.6 h (p = 0.07. Concentration and neuromuscular performance did not change from pre to post testing (0.23 < p < 0.95; 0.001 < ηp² < 0.05. Conclusion: Low-frequent and low cost screen-based point of choice prompts (3 per day within 12 weeks already result in notable increases of occupational standing time of approx. daily 30 min. These stimuli, however, did not relevantly affect neuromuscular outcomes.