The effects of concurrent M1 anodal tDCS and physical therapy interventions on function of ankle muscles in patients with stroke: a randomized,double-blinded sham-controlled trial study

Neurological Sciences - One of the most common symptoms in stroke patients is spasticity. The aims were to investigate the effects of anodal trans-cranial direct current stimulation (a-tDCS) over...     

Relative contributions of infraspinatus and deltoid during external rotation in healthy shoulders

Balanced forces around the shoulder are important for normal function; however, rehabilitation guidelines are not well defined because the muscle contributions and optimal exercise technique to recruit them are poorly understood. This study aimed to determine (1) the conditions of resisted isometric external rotation that optimized the contribution of infraspinatus and (2) the load of external rotation at which the adduction strategy was most effective at reducing deltoid contributions. Eighteen subjects with healthy shoulders (n = 36) performed resisted isometric external rotation at 3 increasing loads--10%, 40%, and 70% of their maximal resisted external rotation voluntary isometric contraction--with and without adduction. Surface electromyographic activity of the infraspinatus, posterior and middle deltoid, and pectoralis major was recorded and normalized against the average activity of all 4 muscles, representing each muscle's relative contribution to the task. To optimize the relative contribution of the infraspinatus with the least deltoid involvement during isometric external rotation, a load between 10% and 40% maximal voluntary isometric contraction is appropriate. At low loads, use of the adduction strategy during external rotation reduces middle deltoid involvement. In contrast, the posterior deltoid is activated in parallel with the infraspinatus at low loads and may even act as an adductor with the arm by the side. This study provides a useful guide to optimize rehabilitative exercises for rotator cuff dysfunction; in particular, highlighting that activation of the deltoid could be counterproductive to infraspinatus retraining.     

Long-term pruritus as the initial and sole clinical manifestation of occult Hodgkin's disease

Pruritus or itch is a frequent symptom of patients with Hodgkin's disease. It often occurs during the clinical course of the disease and rarely may precede the diagnosis of underlying disease. In this report, we present a 16-year-old patient who had history of generalized pruritus without any skin rash for 4 years before the diagnosis of Hodgkin's disease. Within that period, she had received symptom-oriented medications, with no significant effect. After the first cycle of chemotherapy, her pruritus resolved completely. This case suggests that long-term generalized pruritus may be indicative of a significant underlying problem like Hodgkin's disease.     

Experience of patients hospitalized with COVID‐19: A qualitative study of a pandemic disease in Iran

BackgroundThe spread of COVID‐19 as an infectious disease brings about many newly arrived challenges, which call for further research on the scope of its effect on life due to the special conditions of this disease. The present study is, therefore, an attempt to understand the lived experience of inpatients hospitalized with COVID‐19.MethodIn this phenomenological study, among patients with COVID‐19 who were hospitalized in COVID‐19 referral hospitals, 17 people were selected by random sampling method. Data were gathered by interviews and analysed using MAXQDA10 software.FindingsAnalysis revealed 4 main themes and 16 subthemes. Main themes included the (1) denial of the disease, (2) negative emotions upon arrival, (3) perception of social and psychological supports and (4) post‐discharge concerns and problems.ConclusionPatients with COVID‐19 experience a different world of stresses, concerns and feelings in the course of their disease. Gaining a deeper insight into patients’ experiences with this disease can help handle this disease more effectively and provide better post‐corona nursing and psychological care and services.     

a-tDCS Differential Modulation of Corticospinal Excitability: The Effects of Electrode Size

BackgroundNovel noninvasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) have been developed in recent years. tDCS-induced corticospinal excitability changes depend on two important factors: current density and electrodes size. Despite clinical success with existing tDCS parameters; optimal protocols are still not entirely set.ObjectiveThe current study aimed to investigate the effects of anodal tDCS (a-tDCS) with three electrode sizes on corticospinal excitability.Methodsa-tDCS was applied with three active electrode sizes of 12, 24 and 35 cm² with a constant current density of 0.029 mA/cm² on twelve right handed healthy individuals (mean age: 34.5 ± 10.32 years) in different sessions at least 48 h apart. a-tDCS was applied continuously for 10 min, with a constant reference electrode size of 35 cm². The corticospinal excitability of extensor carpi radialis muscle (ECR) was measured before and immediately after the intervention and at 10, 20 and 30 min thereafter.ResultsWe found that smaller electrode may produce more focal current density and could lead to more effective and localized neural modulation than the larger ones. Post hoc comparisons showed that active electrode of 12 cm² size induces the biggest increase in the corticospinal excitability compared to bigger electrode sizes, 24 cm² (P = 0.002) and 35 cm² (P = 0.000). There was no significant difference between two larger electrode sizes (24 cm² and 35 cm²) (P = 0.177). a-tDCS resulted in significant excitability enhancement lasting for 30 min after the end of stimulation in the 12 and 24 cm² electrode size conditions (P < 0.005). However, in 35 cm² electrode size condition, the MEP amplitudes of the ECR did not differ significantly from baseline value in 20 and 30 min post stimulation (P > 0.005).ConclusionReducing stimulation electrode size to one third of the conventional one results in spatially more focused stimulation and increases the efficacy of a-tDCS for induction of larger corticospinal excitability. This may be due to the fact that larger electrodes stimulate nearby cortical functional areas which can have inhibitory effects on primary motor cortex.     

Ultrasound measurement of deep abdominal muscle activity in sitting positions with different stability levels in subjects with and without chronic low back pain

The purpose of this study was to investigate the changes in the thickness of the transversus abdominis (TrA) and internal oblique (IO) muscles in three sitting postures with different levels of stability. The technique of ultrasound imaging was used for individuals with and without chronic low back pain (LBP). A sample of 40 people participated in this study. Subjects were categorised into two groups: with LBP (N = 20) and without LBP (N = 20). Changes in the thickness of tested muscles were normalized under three different sitting postures to actual muscle thickness at rest in the supine lying position and were expressed as a percentage of thickness change. The percentage of thickness change in TrA and IO increased as the stability of the sitting position decreased in both groups. However, the percentages of thickness change in all positions were less in subjects with LBP. There was a significant difference in thickness change in TrA when sitting on a gym ball between subjects with and without LBP but no difference was found when sitting on a chair. There was no significant difference in thickness change in IO in all positions between the two groups. Our findings indicate that difference in the percentage of thickness change in TrA between subjects with and without LBP increases as the stability of sitting position decreases.     

The Effect of 2 Different Exercise Programs on Pain Intensity and Muscle Dimensions in Patients With Chronic Low Back Pain: A Randomized Controlled Trial

Objectives

The purpose of this study was to compare the effect of 2 exercise programs combined with electrotherapy on pain intensity and lumbar stabilizer muscles dimensions in patients with nonspecific chronic low back pain.

The molecular phenotype of human cardiac myosin associated with hypertrophic obstructive cardiomyopathy

AIM: The aim of the study was to compare the functional and structural properties of the motor protein, myosin, and isolated myocyte contractility in heart muscle excised from hypertrophic cardiomyopathy patients by surgical myectomy with explanted failing heart and non-failing donor heart muscle. METHODS: Myosin was isolated and studied using an in vitro motility assay. The distribution of myosin light chain-1 isoforms was measured by two-dimensional electrophoresis. Myosin light chain-2 phosphorylation was measured by sodium dodecyl sulphate-polyacrylamide gel electrophoresis using Pro-Q Diamond phosphoprotein stain. RESULTS: The fraction of actin filaments moving when powered by myectomy myosin was 21% less than with donor myosin (P = 0.006), whereas the sliding speed was not different (0.310 +/- 0.034 for myectomy myosin vs. 0.305 +/- 0.019 microm/s for donor myosin in six paired experiments). Failing heart myosin showed 18% reduced motility. One myectomy myosin sample produced a consistently higher sliding speed than donor heart myosin and was identified with a disease-causing heavy chain mutation (V606M). In myectomy myosin, the level of atrial light chain-1 relative to ventricular light chain-1 was 20 +/- 5% compared with 11 +/- 5% in donor heart myosin and the level of myosin light chain-2 phosphorylation was decreased by 30-45%. Isolated cardiomyocytes showed reduced contraction amplitude (1.61 +/- 0.25 vs. 3.58 +/- 0.40%) and reduced relaxation rates compared with donor myocytes (TT(50%) = 0.32 +/- 0.09 vs. 0.17 +/- 0.02 s). CONCLUSION: Contractility in myectomy samples resembles the hypocontractile phenotype found in end-stage failing heart muscle irrespective of the primary stimulus, and this phenotype is not a direct effect of the hypertrophy-inducing mutation. The presence of a myosin heavy chain mutation causing hypertrophic cardiomyopathy can be predicted from a simple functional assay.