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Widmalm SE, Lee YS, McKay DC. Clinical Use of Qualitative Electromyography in the Evaluation of Jaw Muscle Function: A Practitioner's Guide. Cranio 2014; 25:63-73. [PMID: 17304920 DOI: 10.1179/crn.2007.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Esakov IS, Pechetov AA, Gritsiuta AI. [Choice of diaphragm plasty for acquired relaxation with evidence-based medicine]. Khirurgiia (Mosk) 2014:88-91. [PMID: 25786283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Sharma MG, Upadhyay A, Sharma V. Mental health management of pathological gamblers by counseling and relaxation practices. JOURNAL OF EVIDENCE-BASED SOCIAL WORK 2013; 10:505-508. [PMID: 24066639 DOI: 10.1080/15433714.2012.760960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The present study examines the mental health management of pathological gamblers by counseling and relaxation practices. Fifty-five treated and 55 non-treated pathological gamblers were evaluated at S. I. Mental and Physical Health Society, Varanasi, India. The two groups were matched by age, ranging 20 to 53 years with a mean age of 36.2 years and mean length of uncontrollable gambling of 7.3 years. The Middlesex Hospital Questionnaire and the Death Anxiety Scale were administered to ascertain mental health and death anxiety on seven selected dimensions, including: anxiety, obsession, phobia, somatization, depression, hysteria, and death anxiety. Mean scores obtained on different variables were analyzed using a t-test of significance. Results indicated that the characteristic associated with treated pathological gamblers was phobia whereas the characteristics associated with non-treated pathological gamblers were anxiety, obsession, somatization, depression, and death anxiety.
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Hortemo KH, Munkvik M, Lunde PK, Sejersted OM. Multiple causes of fatigue during shortening contractions in rat slow twitch skeletal muscle. PLoS One 2013; 8:e71700. [PMID: 23977116 PMCID: PMC3745421 DOI: 10.1371/journal.pone.0071700] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/08/2013] [Indexed: 01/18/2023] Open
Abstract
Fatigue in muscles that shorten might have other causes than fatigue during isometric contractions, since both cross-bridge cycling and energy demand are different in the two exercise modes. While isometric contractions are extensively studied, the causes of fatigue in shortening contractions are poorly mapped. Here, we investigate fatigue mechanisms during shortening contractions in slow twitch skeletal muscle in near physiological conditions. Fatigue was induced in rat soleus muscles with maintained blood supply by in situ shortening contractions at 37°C. Muscles were stimulated repeatedly (1 s on/off at 30 Hz) for 15 min against a constant load, allowing the muscle to shorten and perform work. Fatigue and subsequent recovery was examined at 20 s, 100 s and 15 min exercise. The effects of prior exercise were investigated in a second exercise bout. Fatigue developed in three distinct phases. During the first 20 s the regulatory protein Myosin Light Chain-2 (slow isoform, MLC-2s) was rapidly dephosphorylated in parallel with reduced rate of force development and reduced shortening. In the second phase there was degradation of high-energy phosphates and accumulation of lactate, and these changes were related to slowing of muscle relengthening and relaxation, culminating at 100 s exercise. Slowing of relaxation was also associated with increased leak of calcium from the SR. During the third phase of exercise there was restoration of high-energy phosphates and elimination of lactate, and the slowing of relaxation disappeared, whereas dephosphorylation of MLC-2s and reduced shortening prevailed. Prior exercise improved relaxation parameters in a subsequent exercise bout, and we propose that this effect is a result of less accumulation of lactate due to more rapid onset of oxidative metabolism. The correlation between dephosphorylation of MLC-2s and reduced shortening was confirmed in various experimental settings, and we suggest MLC-2s as an important regulator of muscle shortening.
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Lauche R, Materdey S, Cramer H, Haller H, Stange R, Dobos G, Rampp T. Effectiveness of home-based cupping massage compared to progressive muscle relaxation in patients with chronic neck pain--a randomized controlled trial. PLoS One 2013; 8:e65378. [PMID: 23762355 PMCID: PMC3676414 DOI: 10.1371/journal.pone.0065378] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 04/23/2013] [Indexed: 11/18/2022] Open
Abstract
Chronic neck pain is a major public health problem with very few evidence-based complementary treatment options. This study aimed to test the efficacy of 12 weeks of a partner-delivered home-based cupping massage, compared to the same period of progressive muscle relaxation in patients with chronic non-specific neck pain. Patients were randomly assigned to self-directed cupping massage or progressive muscle relaxation. They were trained and asked to undertake the assigned treatment twice weekly for 12 weeks. Primary outcome measure was the current neck pain intensity (0–100 mm visual analog scale; VAS) after 12 weeks. Secondary outcome measures included pain on motion, affective pain perception, functional disability, psychological distress, wellbeing, health-related quality of life, pressure pain thresholds and adverse events. Sixty one patients (54.1±12.7 years; 73.8%female) were randomized to cupping massage (n = 30) or progressive muscle relaxation (n = 31). After treatment, both groups showed significantly less pain compared to baseline however without significant group differences. Significant effects in favor of cupping massage were only found for wellbeing and pressure pain thresholds. In conclusion, cupping massage is no more effective than progressive muscle relaxation in reducing chronic non-specific neck pain. Both therapies can be easily used at home and can reduce pain to a minimal clinically relevant extent. Cupping massage may however be better than PMR in improving well-being and decreasing pressure pain sensitivity but more studies with larger samples and longer follow-up periods are needed to confirm these results. Trial Registration ClinicalTrials.gov NCT01500330
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Hu B, Ning X, Nimbarte AD. The changes of lumbar muscle flexion-relaxation response due to laterally slanted ground surfaces. ERGONOMICS 2013; 56:1295-1303. [PMID: 23730975 DOI: 10.1080/00140139.2013.803161] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
UNLABELLED Lifting tasks performed on uneven ground surfaces are common in outdoor industries. Previous studies have demonstrated that lifting tasks performed on laterally slanted ground surfaces influence lumbar muscle activation and trunk kinematics. In this study, the effect of laterally slanted ground surfaces on the lumbar muscle flexion-relaxation responses was investigated. Fourteen participants performed sagittal plane, trunk flexion-extension tasks on three laterally slanted ground surfaces (0° (flat ground), 15° and 30°), while lumbar muscle activities and trunk kinematics were recorded. Results showed that flexion-relaxation occurred up to 6.2° earlier among ipsilateral lumbar muscles with an increase in laterally slanted ground angle; however, the contralateral side was not affected as much. Our findings suggest that uneven ground alters the lumbar tissue load-sharing mechanism and creates unbalanced lumbar muscle activity, which may increase the risk of low back pain with repeated exposure to lifting on variable surfaces. PRACTITIONER SUMMARY Uneven ground surfaces are ubiquitous in agriculture, construction, fishing and other outdoor industries. A better understanding of the effects of laterally slanted ground surfaces on the interaction between passive and active lumbar tissues during lifting tasks could provide valuable knowledge in the design of preventive strategies for low back injuries.
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Tao L, Hu HS, Shen XC. Endothelium-dependent vasodilatation effects of the essential oil from Fructus alpiniae zerumbet (EOFAZ) on rat thoracic aortic rings in vitro. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2013; 20:387-393. [PMID: 23369344 DOI: 10.1016/j.phymed.2012.12.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 11/25/2012] [Accepted: 12/25/2012] [Indexed: 06/01/2023]
Abstract
Fructus Alpiniae Zerumbet (FAZ) is an herb widely used to treat vascular disorders in Guizhou province, China, the essential oil has been identified as one of it vasodilation effect active components, and especial, the composition was significantly difference from the leaves. Vasodilation effects and mechanism of essential oil from FAZ (EOFAZ) were investigated. The EOFAZ showed significant vasodilation effect on endothelium-with rat thoracic aortic rings preincubated with norepinephrine (NE, 1.0μM) or KCl (60mM) in a concentration-dependent manner (1.14-72.96μg/ml). The non-selective nitric oxide synthase inhibitor l-NAME, as well as the soluble guanylate cyclase inhibitor MB, attenuated the relaxation of EOFAZ in endothelium-intact rat thoracic aortic rings. However, there were not significantly affected the vasodilation effects pretreated with cyclooxygenase inhibition by indomethacin (Indo) or β-noradrenergic inhibition by propranolol (Prop). The present results first demonstrated that vasodilation effect of EOFAZ depending upon the endothelium and concentration, and the mechanism involvement of NOS-cGMP system. In contrast, prostacyclin and β-adrenoceptor may not be associated with EOFAZ-induced vasorelaxation.
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Jorge JX, Borges CIC, Panão EA, Delgado FJ, Simões MA, Coelho ÁC, Silva AL, Almeida CC. Recto-anal manometric characteristics of type 2 diabetic patients who have sensation of incomplete defecation. J Diabetes Complications 2013; 27:167-70. [PMID: 23312216 DOI: 10.1016/j.jdiacomp.2012.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Many diabetic patients report symptoms of incomplete defecation. We aimed to clarify the recto-anal manometric characteristics related to these symptoms. MATERIAL AND METHODS A questionnaire regarding gastrointestinal symptoms was distributed to 35 diabetics (19 women and 16 men) aged between 39 and 81 years. Nineteen reported incomplete defecation sensation (WS) and 16 did not (NS). Recto-anal manometry was performed for all patients. Data are presented as mean±SD. RESULTS Resting rectal pressure was 14.4±10.1 mmHg and 8.8±3.9 mmHg, p<.03; first sensation was 61.0±27.8 ml and 83.1±35.7 ml, p<.04; and maximum tolerable volume was 174.2±81.5 ml and 235.0±89.5 ml, p<.04 for WS and NS, respectively. The WS group was further divided into 2 groups according to symptom severity (less severe and very severe). Significant differences were found in resting external anal sphincter pressure (50.4±15.6 and 34.3±17.4, p<.04) and the recto anal inhibitory reflex (48.6±19.8 and 26.3±23.2, p<.03) between the less severe and very severe groups, respectively. CONCLUSIONS (1) Resting rectal pressure was significantly higher in symptomatic individuals. (2) First sensation and maximum tolerable volume were higher in asymptomatic diabetics. (3) In diabetics with more severe symptoms, the resting external anal sphincter pressures were significantly lower. (4) The degree of relaxation in the recto-anal inhibitory reflex was significantly higher in individuals without complaints.
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Dada J, Pinder AG, Lang D, James PE. Oxygen mediates vascular smooth muscle relaxation in hypoxia. PLoS One 2013; 8:e57162. [PMID: 23451175 PMCID: PMC3579807 DOI: 10.1371/journal.pone.0057162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 01/18/2013] [Indexed: 11/19/2022] Open
Abstract
The activation of soluble guanylate cyclase (sGC) by nitric oxide (NO) and other ligands has been extensively investigated for many years. In the present study we considered the effect of molecular oxygen (O2) on sGC both as a direct ligand and its affect on other ligands by measuring cyclic guanosine monophosphate (cGMP) production, as an index of activity, as well as investigating smooth muscle relaxation under hypoxic conditions. Our isolated enzyme studies confirm the function of sGC is impaired under hypoxic conditions and produces cGMP in the presence of O2, importantly in the absence of NO. We also show that while O2 could partially affect the magnitude of sGC stimulation by NO when the latter was present in excess, activation by the NO independent, haem-dependent sGC stimulator 3-(5′-hydroxymethyl-2′-furyl)-1-benzylindazole (YC-1) was unaffected. Our in vitro investigation of smooth muscle relaxation confirmed that O2 alone in the form of a buffer bolus (equilibrated at 95% O2/5% CO2) had the ability to dilate vessels under hypoxic conditions and that this was dependent upon sGC and independent of eNOS. Our studies confirm that O2 can be a direct and important mediator of vasodilation through an increase in cGMP production. In the wider context, these observations are key to understanding the relative roles of O2 versus NO-induced sGC activation.
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85
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Dubois PE, Mulier JP. A review of the interest of sugammadex for deep neuromuscular blockade management in Belgium. ACTA ANAESTHESIOLOGICA BELGICA 2013; 64:49-60. [PMID: 24191526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Oro-tracheal intubation and selected surgical conditions are facilitated by a deep neuromuscular block (NMB), but patient's security can be jeopardized by its residual effects at the time of tracheal extubation. Although neostigmine remains the reference reversal agent in many situations, the limitations of its efficacy must be well understood (ceiling effect, delay of action, side effects). It is best administered after re-emergence of the 3rd or 4th train-of-four (TOF) response. Sugammadex causes more predictable and more rapid recoveries from much deeper rocuronium-induced NMB. Therefore, maintaining deep NMB during surgery is no longer incompatible with rapid recovery and safe extubation. In Belgium, the use of sugammadex and its reimbursement depend on specific conditions. The excellent clinical tolerance of sugammadex benefits to patients at risk of developing complications related to residual NMB or to the undesirable effects of neostigmine. In all cases, neuromuscular transmission monitoring is the key to adequate NMB management.
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Czaprowski D, Leszczewska J, Kolwicz A, Pawłowska P, Kędra A, Kriščiūnas A, Raistenskis J, Kowalski IM. The influence of self-stretching based on postisometrical relaxation, static stretching combined with stabilizing exercises, and stabilizing exercises only on the flexibility of one-joint and two-joint hip flexors. MEDICINA (KAUNAS, LITHUANIA) 2013; 49:439-446. [PMID: 24709786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND AND OBJECTIVE. The limitations of muscle flexibility are a common dysfunction of the musculoskeletal system. Therefore, various therapeutic techniques are used in rehabilitation programs to increase their flexibility. The aim of this prospective, randomized, single-blind study was to evaluate the changes in the flexibility of hip flexors in children who participated in a 6-week therapeutic program consisting of one physiotherapy session per week with a physiotherapist and daily home exercises. MATERIAL AND METHODS. A total of 94 children aged 10-13 years were randomly assigned to 3 experimental groups: postisometrical relaxation group (PIR group), static stretching combined with stabilizing exercise group (SE/SS group), and stabilizing exercise group (SS group). To assess the flexibility of one- and two-joint hip flexors, the modified Thomas test was used. The examination was conducted by blinded observers. RESULTS. A significant improvement in the flexibility of one-joint hip flexors was documented in all 3 groups (P<0.01). The flexibility of two-joint hip flexors increased significantly only in the SS/SE group (P<0.05). After the program, the highest range of motion of the hip extension (test for one-joint hip flexors) was recorded in the SS/SE group (20.6° ± 4.5°), and it was significantly greater than in the SE group (16.6° ± 4.0°, P<0.05). There were no significant differences in the knee flexion (test for two-joint hip flexors) among all 3 groups (P>0.05). CONCLUSIONS. The 6-week therapeutic program regardless of the technique applied (postisometrical muscle relaxation, static stretching with stabilizing exercises, and stabilizing exercises only) resulted in the increased flexibility of one-joint hip flexors. Only static stretching combined with stabilizing exercises led to a significant increase in the flexibility of two-joint hip flexors.
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87
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Yeung Y. Distraction techniques for anxious dental patients an arising field in analgesia for modern dentistry. SAAD DIGEST 2013; 29:82-87. [PMID: 23544225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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88
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Lachance PA. Reduction of shoulder dislocation: are communication and adequate relaxation more important than technique? CANADIAN FAMILY PHYSICIAN MEDECIN DE FAMILLE CANADIEN 2012; 58:1189-e614. [PMID: 23152452 PMCID: PMC3498008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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89
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Dayapoğlu N, Tan M. Evaluation of the effect of progressive relaxation exercises on fatigue and sleep quality in patients with multiple sclerosis. J Altern Complement Med 2012; 18:983-7. [PMID: 22967281 PMCID: PMC3469207 DOI: 10.1089/acm.2011.0390] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Fatigue and sleep problems are very commonly observed in patients with multiple sclerosis (MS). The Progressive Muscle Relaxation Technique (PMRT), used as one of the alternative methods in recent years, is reported to have benefits such as facilitating sleep and reducing sensitivity against fatigue. This research was conducted to investigate the effect of PMRT on fatigue and sleep quality in patients with MS. SETTING AND DESIGN This research was performed as a single-group pretest/post-test pretrial model. The research was conducted between March 2008 and December 2009 in the neurology polyclinic. MATERIALS AND METHODS The study was conducted with 32 patients who met the research criteria and agreed to participate in the study. A Personal Information Form was used as a data collection tool, Fatigue Severity Scale was used for measuring fatigue, and the Pittsburgh Sleep Quality Index was used for evaluating the sleep quality. PMRT was applied to the sample group once a day for 6 weeks. STATISTICAL ANALYSIS Percentage, paired t-test, and Pearson's correlation analysis were used in the assessment of data. RESULTS It was determined that PMRT decreased patients' fatigue level and improved their sleep quality, and this difference was observed to be statistically significant. Moreover, patients' fatigue level increased as their sleep quality decreased. CONCLUSIONS This study supports the effect of PMRT on fatigue and sleep quality in patients with MS, and it is recommended that further studies be conducted on this subject in the future.
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Lee EJ, Bhattacharya J, Sohn C, Verres R. Monochord sounds and progressive muscle relaxation reduce anxiety and improve relaxation during chemotherapy: a pilot EEG study. Complement Ther Med 2012; 20:409-16. [PMID: 23131371 DOI: 10.1016/j.ctim.2012.07.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 03/31/2012] [Accepted: 07/05/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Chemotherapy is the most distressing form of cancer treatment in oncology, but listening to music can be an adjuvant during chemotherapy. Monochord (MC) sounds are used in music therapy for the alleviation of pain, enhanced body perception, and relaxation. This study investigated the relaxation effect of MC sounds for patients during chemotherapy compared with progressive muscle relaxation (PMR), an established relaxation technique. METHODOLOGY/PRINCIPAL FINDINGS Two randomized groups of patients were observed during chemotherapy. One group listened to recorded MC sounds (n=20) and the other group listened to recorded PMR (n=20). Each session was investigated pre and post using Spielberger's State Anxiety Inventory (SAI) and a questionnaire about the patient's physical and psychological states. Further, for the first and the last session, multivariate electroencephalogram (EEG) signals were recorded. Patients in both MC and PMR groups showed significant improvement in their physical and psychological states and in state anxiety. The EEG data showed that the MC and the PMR groups were associated with an increase of posterior theta (3.5-7.5 Hz) and a decrease of midfrontal beta-2 band (20-29.5 Hz) activity during the end phase of relaxation treatment. Further, the MC group was associated with decreased alpha band (8-12 Hz) activity in comparison with PMR group. CONCLUSIONS This study shows that both listening to recorded MC sounds and practising PMR have a useful and comparable effect on gynaecologic oncological patients during chemotherapy, with partially overlapping but also notably divergent neural correlates. Future research should establish the systematic use of MC in oncological contexts.
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91
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Halder A. Effect of progressive muscle relaxation versus intake of ginger powder on dysmenorrhoea amongst the nursing students in Pune. THE NURSING JOURNAL OF INDIA 2012; 103:152-6. [PMID: 23534170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The present study was conducted to examine the comparative efficacy of progressive muscle relaxation and the oral intake of ginger on symptoms of dysmenorrhoea among nursing students of Pune, Maharashtra. The study students (n = 75) were divided into three groups, two experimental and one control Ginger powder 1 gm per dose was administered twice a day with warm water after meal to the second experimental group during the first three days of their menstruation. Main outcome measures were the severity of selected symptoms of dysmenorrhoea. The daily symptom calendar, a 5-point Likert Scale was used to assess the severity of selected symptoms of dysmenorrhoea. Main outcome measures were the severity of selected symptoms of dysmenorrhoea, which were analysed using MANOVA. It was concluded that in treating symptoms of dysmenorrhoea, ginger powder has efficacy superior to progressive muscle relaxation.
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Nunes PM, van de Weijer T, Veltien A, Arnts H, Hesselink MKC, Glatz JFC, Schrauwen P, Tack CJ, Heerschap A. Increased intramyocellular lipids but unaltered in vivo mitochondrial oxidative phosphorylation in skeletal muscle of adipose triglyceride lipase-deficient mice. Am J Physiol Endocrinol Metab 2012; 303:E71-81. [PMID: 22496349 DOI: 10.1152/ajpendo.00597.2011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Adipose triglyceride lipase (ATGL) is a lipolytic enzyme that is highly specific for triglyceride hydrolysis. The ATGL-knockout mouse (ATGL(-/-)) accumulates lipid droplets in various tissues, including skeletal muscle, and has poor maximal running velocity and endurance capacity. In this study, we tested whether abnormal lipid accumulation in skeletal muscle impairs mitochondrial oxidative phosphorylation, and hence, explains the poor muscle performance of ATGL(-/-) mice. In vivo ¹H magnetic resonance spectroscopy of the tibialis anterior of ATGL(-/-) mice revealed that its intramyocellular lipid pool is approximately sixfold higher than in WT controls (P = 0.0007). In skeletal muscle of ATGL(-/-) mice, glycogen content was decreased by 30% (P < 0.05). In vivo ³¹P magnetic resonance spectra of resting muscles showed that WT and ATGL(-/-) mice have a similar energy status: [PCr], [P(i)], PCr/ATP ratio, PCr/P(i) ratio, and intracellular pH. Electrostimulated muscles from WT and ATGL(-/-) mice showed the same PCr depletion and pH reduction. Moreover, the monoexponential fitting of the PCr recovery curve yielded similar PCr recovery times (τPCr; 54.1 ± 6.1 s for the ATGL(-/-) and 58.1 ± 5.8 s for the WT), which means that overall muscular mitochondrial oxidative capacity was comparable between the genotypes. Despite similar in vivo mitochondrial oxidative capacities, the electrostimulated muscles from ATGL(-/-) mice displayed significantly lower force production and increased muscle relaxation time than the WT. These findings suggest that mechanisms other than mitochondrial dysfunction cause the impaired muscle performance of ATGL(-/-) mice.
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Chuan P, Sivaramakrishnan S, Ashley EA, Spudich JA. Cell-intrinsic functional effects of the α-cardiac myosin Arg-403-Gln mutation in familial hypertrophic cardiomyopathy. Biophys J 2012; 102:2782-90. [PMID: 22735528 DOI: 10.1016/j.bpj.2012.04.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 04/02/2012] [Accepted: 04/13/2012] [Indexed: 01/27/2023] Open
Abstract
Human familial hypertrophic cardiomyopathy is the most common Mendelian cardiovascular disease worldwide. Among the most severe presentations of the disease are those in families heterozygous for the mutation R403Q in β-cardiac myosin. Mice heterozygous for this mutation in the α-cardiac myosin isoform display typical familial hypertrophic cardiomyopathy pathology. Here, we study cardiomyocytes from heterozygous 403/+ mice. The effects of the R403Q mutation on force-generating capabilities and dynamics of cardiomyocytes were investigated using a dual carbon nanofiber technique to measure single-cell parameters. We demonstrate the Frank-Starling effect at the single cardiomyocyte level by showing that cell stretch causes an increase in amplitude of contraction. Mutant 403/+ cardiomyocytes exhibit higher end-diastolic and end-systolic stiffness than +/+ cardiomyocytes, whereas active force generation capabilities remain unchanged. Additionally, 403/+ cardiomyocytes show slowed relaxation dynamics. These phenotypes are consistent with increased end-diastolic and end-systolic chamber elastance, as well as diastolic dysfunction seen at the level of the whole heart. Our results show that these functional effects of the R403Q mutation are cell-intrinsic, a property that may be a general phenomenon in familial hypertrophic cardiomyopathy.
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Kraus D. [With hypnosis, progressive muscle relaxation and co. This is how pain memory fades]. MMW Fortschr Med 2012; 154:22-23. [PMID: 22803233 DOI: 10.1007/s15006-012-0661-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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95
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Kimelman C. [Relaxation techniques in general practice. Get away from passivity (interiview By Dr. Dagmar Kraus)]. MMW Fortschr Med 2012; 154:23. [PMID: 22803234 DOI: 10.1007/s15006-012-0662-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Knowles AC, Irving M, Sun YB. Conformation of the troponin core complex in the thin filaments of skeletal muscle during relaxation and active contraction. J Mol Biol 2012; 421:125-37. [PMID: 22579625 DOI: 10.1016/j.jmb.2012.05.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 04/25/2012] [Accepted: 05/03/2012] [Indexed: 01/13/2023]
Abstract
Contraction of skeletal and cardiac muscles is regulated by Ca(2+) binding to troponin in the actin-containing thin filaments, leading to an azimuthal movement of tropomyosin around the filament that uncovers the myosin binding sites on actin. Here, we use polarized fluorescence to determine the orientation of the C-terminal lobe of troponin C (TnC) in skeletal muscle cells as a step toward elucidating the molecular mechanism of troponin-mediated regulation. Assuming, as shown by X-ray crystallography, that this lobe of TnC is part of a well-defined troponin domain called the IT arm, we show that the coiled coil formed by troponin components I and T makes an angle of about 55° with the thin filament axis in relaxed muscle, in contrast with previous models based on electron microscopy in which this angle is close to 0°. The E helix of TnC makes an angle of about 45° with the thin filament axis. Both the IT coiled coil and the TnC E helix tilt by about 10° on muscle activation. By combining in situ measurements of the orientation of the IT arm and regulatory domain of troponin, which together form the troponin core complex, with published intermolecular distances between thin filament components, we derive models of thin filament structure in which the IT arm of troponin holds its regulatory domain close to the actin surface. Although the structure and function of troponin regions outside the core complex remain to be characterized, the present results provide useful constraints for molecular models of the mechanism of muscle regulation.
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Shimokawa H. Vasodilation regulated by H2O2. Nihon Yakurigaku Zasshi 2012; 139:229. [PMID: 22993887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Peterson LR, Saeed IM, McGill JB, Herrero P, Schechtman KB, Gunawardena R, Recklein C, Coggan AR, DeMoss AJ, Dence CS, Gropler RJ. Sex and type 2 diabetes: obesity-independent effects on left ventricular substrate metabolism and relaxation in humans. Obesity (Silver Spring) 2012; 20:802-10. [PMID: 21818149 PMCID: PMC3314727 DOI: 10.1038/oby.2011.208] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Patients with type 2 diabetes (T2DM), particularly women, are at risk for heart failure. Myocardial substrate metabolism derangements contribute to cardiac dysfunction in diabetic animal models. The purpose of this study was to determine the effects of diabetes and sex on myocardial metabolism and diastolic function in humans, separate from those of obesity. Thirty-six diabetic subjects (22 women) and 36 nondiabetic, BMI-matched subjects (21 women) underwent positron emission tomography (myocardial metabolism) and echocardiography (structure, function). Myocardial blood flow and oxygen consumption (MVO(2)) were higher in women than men (P = 0.003 and <0.0001, respectively). Plasma fatty acid (FA) levels were higher in diabetics (vs. obese, P < 0.003) and sex and diabetes status interacted in its prediction (P = 0.03). Myocardial FA utilization, oxidation, and esterification were higher and percent FA oxidation lower in diabetics (vs. obese, P = 0.0004, P = 0.007, P = 0.002, P = 0.02). FA utilization and esterification were higher and percent FA oxidation lower in women (vs. men, P = 0.03, P = 0.01, P = 0.03). Diabetes and sex did not affect myocardial glucose utilization, but myocardial glucose uptake/plasma insulin was lower in the diabetics (P = 0.04). Left ventricular relaxation was lower in diabetics (P < 0.0001) and in men (P = 0.001), and diabetes and sex interacted in its prediction (P = 0.03). Sex, T2DM, or their interaction affect myocardial blood flow, MVO(2), FA metabolism, and relaxation separate from obesity's effects. Sexually dimorphic myocardial metabolic and relaxation responses to diabetes may play a role in the known cardiovascular differences between men and women with diabetes.
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Koriak IA. [Contraction properties and musculo-tendinous stiffness of the human triceps surae muscle and their change as a result of a long-term bed-rest]. FIZIOLOHICHNYI ZHURNAL (KIEV, UKRAINE : 1994) 2012; 58:66-79. [PMID: 22873055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The effect of a 120-day 5 degree head-down tilt (HDT) bed rest on the mechanical properties and electromechanical delay (EMD) of the human triceps surae (TS) muscle was studied in four (mean age 31.5+/-1.7 yr) healthy young women subjects. The TS mechanical properties were evaluated based on the following indicators: maximal voluntary contraction (MVC), maximal strength (Po; frequency 150 Hz), peak twitch force (Poc), time-to-peak tension (TPT), half-relaxation time (1/2 RT) and tension development time to reach 25, 50, 75 and 90% of maximal tension. Force deficit (Pd) were estimated. In response to a light signal,the subject was supposed to make a voluntary foot flexion, with the instruction "to exert the fastest and greatest tension". EMD measurements were recorded from each subject during voluntary contraction. Surface electrodes sensed electromyographic (EMG) activity in the soleus muscle. A separate timer was used to determine total reaction time (TRT). Premotor time (PMT) was taken to be the time interval from the delivery of the signal to change in EMG. EMD was the time interval between the change in EMG and movement i.e. the time interval between EMG and the onset of muscle tension. After HDT Poe, MVC and Po decreased by 24.4, 36.1 and 11.5%, respectively, while Pd increased by 38.8%. TPT increased by 13.6%, while 1/2RT decreased by 19.2%. The rate of increase of voluntary contractions calculated according to a relative scale significantly increased, while the rate of development of electrically evoked contraction did not show any significant differences. The voluntary contraction EMD increased by 27.4%; PMT by 8.7%, and TRT by 13.6%. Thus, the mechanical changes suggest that weightlessness changes not only the peripheral processes associated with contractions but also the central and neural command. EMD is a simple and quick method for evaluation of muscle stiffness changes. Moreover, EMD can serve as an indicator of the functional condition of the neuromuscular system.
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Bae BG, Oh SH, Park CO, Noh S, Noh JY, Kim KR, Lee KH. Progressive muscle relaxation therapy for atopic dermatitis: objective assessment of efficacy. Acta Derm Venereol 2012; 92:57-61. [PMID: 21879233 DOI: 10.2340/00015555-1189] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The aims of this study were to validate the efficacy of progressive muscle relaxation (PMR) in patients with atopic dermatitis and to evaluate the serological parameters that may serve as objective measures of the efficacy of PMR. A total of 25 patients with atopic dermatitis were randomly assigned to either a PMR group (n = 15) or a control group (n = 10). Serum levels of nerve growth, neuropeptide Y, and Th2 cytokines (IL-4, IL-5, and IL-13) were measured at baseline and after one month. At baseline, only anxiety was positively correlated with pruritus score (state anxiety: R = 0.496, p = 0.014; trait anxiety: R = 0.423, p = 0.04). Serum levels of neuropeptide Y were inversely related to the State-Trait Anxiety Inventory (STAI) (state anxiety: R = -0.475, p = 0.019; trait anxiety: R = -0.418, p = 0.042) and pruritus scores (R = -0.451, p = 0.035). After one month of PMR therapy, the degree of pruritus and loss of sleep was significantly decreased in the PMR group (p < 0.001), but not among controls. State anxiety scores showed significant improvement after treatment only in the PMR group (p = 0.005). There were no significant changes in the serological parameters in either group. Reductions in Eczema Area and Severity Index (EASI) scores were significant, but similar, in both groups. PMR may be a useful adjunctive modality for the management of atopic dermatitis through the reduction of anxiety. No change was found in biological parameters, but it was observed that neuropeptide Y may be related to high levels of anxiety in atopic dermatitis at baseline.
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