scholarly journals Blinding in electric current stimulation in subacute neglect patients with current densities of 0.8 A/m2: a cross-over pilot study

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Anna Gorsler ◽  
Ulrike Grittner ◽  
Nadine Külzow ◽  
Torsten Rackoll

Abstract Objective Neglect after stroke is a disabling disorder and its rehabilitation is a major challenge. Transcranial direct current stimulation (tDCS) seems to be a promising adjuvant technique to improve standard care neglect therapy. Since electric fields are influenced by age-related factors, higher current densities are probably needed for effective treatment in aged stroke patients. Validation of treatment efficacy requires sham-controlled experiments, but increased current densities might comprise blinding. Therefore, a pilot study was conducted to test sham adequacy when using current density of 0.8 A/m2. Whether especially neglect patients who mainly suffer from perceptual and attentional deficits are able to differentiate beyond chance active from sham tDCS was investigated in a randomized cross-over design (active/sham stimulation) in 12 early subacute patients with left-sided hemineglect. Stimulation (0.8 A/m2) was performed simultaneous to standard care neglect therapy. Results Odds ratio of correct guessing an atDCS condition compared to wrongly judge an atDCS condition as sham was 10.00 (95%CI 0.65–154.40, p = 0.099). However, given the small sample size and high OR, although likely somewhat overestimated, results require careful interpretation and blinding success in neglect studies with current densities of 0.8 A/m2 should be further confirmed.

2020 ◽  
Author(s):  
Anna Gorsler ◽  
Ulrike Grittner ◽  
Nadine Külzow ◽  
Torsten Rackoll

Abstract Objective Neglect after stroke is a disabling disorder and its rehabilitation is a major challenge. Transcranial direct current stimulation (tDCS) seems to be a promising adjuvant technique to improve standard care neglect therapy. Since electric fields are influenced by age-related factors, higher current densities are probably needed for effective treatment in aged stroke patients. Validation of treatment efficacy requires sham-controlled experiments, but increased current densities might comprise blinding. Therefore, a pilot study was conducted to test sham adequacy when using current density of 0.8 A/m2. Whether especially neglect patients who mainly suffer from perceptual and attentional deficits are able to differentiate beyond chance active from sham tDCS was investigated in a randomized cross-over design (active/sham stimulation) in 12 early subacute patients with left-sided hemineglect. Stimulation (0.8 A/m²) was performed simultaneous to standard care neglect therapy. Results Odds ratio of correct guessing an atDCS condition compared to wrongly judge an atDCS condition as sham was 10.00 (95%CI: 0.65 - 154.40, p = 0.099). However, given the small sample size and high OR, although likely somewhat overestimated, results require careful interpretation and blinding success in neglect studies with current densities of 0.8 A/m² should be further confirmed.


2020 ◽  
Author(s):  
Anna Gorsler ◽  
Ulrike Grittner ◽  
Nadine Külzow ◽  
Torsten Rackoll

Abstract Objective: Neglect after stroke is a disabling disorder and its rehabilitation is a major challenge. Transcranial direct current stimulation (tDCS) seems to be a promising adjuvant technique to improve standard care neglect therapy. Since electric fields are influenced by age-related factors, higher current densities are probably needed for effective treatment in aged stroke patients. Validation of treatment efficacy requires sham-controlled experiments but increased current densities might comprise blinding. Therefore, we conducted a pilot study to test sham adequacy when using current density of 0.8 A/m2. Whether especially neglect patients who mainly suffer from perceptual and attentional deficits are able to differentiate beyond chance active from sham tDCS was investigated in a randomized cross-over design (active/sham stimulation) in 12 early subacute patients with left-sided hemineglect. Stimulation (0.8 A/m²) was performed simultaneous to standard care neglect therapy. Progress of neglect symptomatology was also monitored during inpatient rehabilitation.Results: Odds ratio of correct guessing an atDCS condition compared to wrongly judge an atDCS condition as sham was 10.00 (95%CI: 0.65 - 154.40, p = 0.099). However, due to small sample size results must be interpreted with caution and blinding success in neglect studies with current densities of 0.8 A/m² still warrants further investigation.


2020 ◽  
Author(s):  
Anna Gorsler ◽  
Ulrike Grittner ◽  
Nadine Külzow ◽  
Torsten Rackoll

Abstract Objective Neglect after stroke is a disabling disorder and its rehabilitation is a major challenge. Transcranial direct current stimulation (tDCS) seems to be a promising adjuvant technique to improve standard care neglect therapy. Since electric fields are influenced by age-related factors higher current densities are probably needed for effective treatment in aged stroke patients. The validation of treatment efficacy requires sham-controlled experiments but increased current densities might comprise blinding. Therefore, we conducted a pilot study to test sham adequacy when using current density of 0.8 A/m2. Whether especially neglect patients who mainly suffer from perceptual and attentional deficits are able to differentiate beyond chance active from sham tDCS was investigated in a cross-over design (active/sham stimulation, randomized order) in 12 early subacute patients with left-sided hemineglect. Stimulation was performed simultaneous to standard care neglect therapy with 0.8 A/m². Progress of neglect symptomatology was also monitored during inpatient rehabilitation.Results Higher odds of correct guessing an active tDCS condition compared to wrongly judge an active tDCS condition as sham stimulation (Odds ratio 10.00, 95%CI: 0.65 - 154.40, p = 0.099) were observed. Therefore, blinding success remains debatable in neglect studies with current densities of 0.8 A/m² and still warrants further investigation.


2020 ◽  
Author(s):  
Anna Gorsler ◽  
Ulrike Grittner ◽  
Nadine Külzow ◽  
Torsten Rackoll

Abstract Objective Transcranial direct current stimulation (tDCS) is a promising adjuvant technique to improve standard care neglect therapy in patients suffering from stroke. Current densities in tDCS are modeled by tissue distribution in the brain. Therefore, we hypothesized that higher current densities are needed in aged stroke population to counteract age related brain volume loss. Here it is still unresolved whether blinding of participants can be achieved. Our aim was to test whether stroke patients with left-sided hemineglect are able to differentiate beyond chance active tDCS from sham stimulation at a current density of 0.8 A/m². Therefore, we investigated 12 early subacute stroke patients with left-sided hemineglect in a cross-over design with two stimulation settings (active/sham stimulation in randomized order). Stimulation was performed simultaneous to standard care neglect therapy with 0.8 A/m² and progress of neglect symptomatology was monitored during inpatient rehabilitation.Results Our sample exhibited higher odds of correct guessing an active tDCS condition compared to wrongly judge an active tDCS condition as sham stimulation (Odds ratio 10.00, 95%CI: 0.65 - 154.40, p = 0.099). Therefore, we must question the feasibility of blinding success in studies with current densities of 0.8 A/m². Assessment in multisession protocols still warrants further investigation.


2021 ◽  
Vol 13 (11) ◽  
pp. 6285
Author(s):  
Sandra Misiak-Kwit ◽  
Małgorzata Wiścicka-Fernando ◽  
Kelaniyage Shihan Dilruk Fernando

In this manuscript, the authors aim to explore firstly the association between entrepreneurial mindset and co-creation experience, secondly the association between co-creation experience and entrepreneurial intentions, and thirdly the association between entrepreneurial mindset and entrepreneurial intentions within the sustainability context. In this paper, the authors present the results of the pilot study. Primary data were collected from 500 university students from China, Georgia, Poland, Romania, and Sri Lanka by using a convenient sampling technique, and a literature review was the primary method of the concept development. The authors selected the above-mentioned countries to collect primary data by using a convenient sampling technique based on accessibility; they also visited all analysed countries in order to conduct the pilot survey personally. Descriptive statistics and the Spearman’s rank correlation coefficient were applied as primary statistical methods. The findings reveal that there is a very strong association between co-creation experience and entrepreneurial intentions, a very weak negative association between entrepreneurial mindset and co-creation experience, and, surprisingly, a weak association between entrepreneurial mindset and entrepreneurial intentions. The added value of the conducted pilot research involves filling in a gap regarding the relationship between experience and the subjective norm. In the presented pilot research, co-creation experience was compared with not only entrepreneurial mindset but with entrepreneurial intentions as well. An additional value of this exploratory research is compiling an international comparison. The main contribution of this pilot study is examining the symbiotic mutualism between co-creation and entrepreneurship. Among many platforms of associations, the following can be differentiated: creativity, innovativeness, openness, engagement, awareness, motivation, trust (level of social capital), and recognizing the significance of social and sustainable development objectives. Due to the small sample size, the results cannot be generalised. Results refer only to the respondents. However, the findings of the pilot study are the basis for further research studies on symbiotic mutualism between entrepreneurship and co-creation.


2021 ◽  
pp. 193229682110111
Author(s):  
Sarah Nadeem ◽  
Uswah Siddiqi ◽  
Russell Seth Martins ◽  
Kaleemullah Badini

Introduction: Diabetes mellitus technology (DMT) is increasingly used for routine management in developed countries, yet its uptake in developing countries is not as consistent. Multiple factors may influence this, including country specific patient perception regarding DMT. We conducted a pilot study in Pakistan to understand this important question which has not been studied yet. Methods: A cross-sectional pilot study was conducted in Pakistan. An anonymous survey exploring perceptions of diabetes technology was circulated on social media platforms, collecting responses over 2 weeks. Target population included adults (≥18 years) living in Pakistan, with DM1 or 2. Results: A total of 40 responses were received. The majority (36/40) reported using conventional glucometers. Nine used continuous glucose monitoring (CGM). Thirty-two of 40 patients believed DMT improved diabetes care, 22 felt it helped decreased risk of Diabetes-related complications. 15/40 stated that DMT results in increased cost of care. Sixteen reported their diabetes care teams had never discussed wearable DMT options whereas 11 disliked them because they did not want a device on their self. Conclusion: In our pilot study we have identified broad themes of opportunity and challenges to DMT use in Pakistan. Patients’ perceptions regarding DMT were generally positive but significant barriers to its acceptance included high cost, lack of discussion between doctor and patient about available technology and personal hesitation. Limitations of our study include sampling bias (online survey) and small sample size, but this data can help inform larger studies, to look at this important topic in greater detail.


2012 ◽  
Vol 97 (11) ◽  
pp. 3989-3995 ◽  
Author(s):  
A. Valcour ◽  
F. Blocki ◽  
D. M. Hawkins ◽  
Sudhaker D. Rao

Context: Several studies define optimal serum 25-hydroxyvitamin D (25-OHD) levels based on serum PTH level reaching an asymptote. However, results differ widely, ranging from 25-OHD levels of 12–44 ng/ml: many studies are constrained by small sample size. Objective: The objective of the study was to determine the relationship between serum PTH and 25-OHD levels and age in a very large reference laboratory database. Design: This was a detailed cross-sectional analysis of 312,962 paired serum PTH and 25-OHD levels measured from July 2010 to June 2011. Results: Median PTH levels and the proportion of patients (PTH > 65 pg/ml), from 63 successive 25-OHD frequency classes of 5000 patients, provide smooth, exceptionally well-fitted curves (R2 = 0.994 and R2 = 0.995, respectively) without discernible inflection points or asymptotes but with striking age dependencies. Serum 25-OHD was below the recent Institute of Medicine sufficiency guidance of 20 ng/ml in 27% (85,000) of the subjects. More importantly, 40 and 51% of subjects (serum 25-OHD <20 and 10 ng/ml, respectively) had biochemical hyperparathyroidism (PTH > 65 pg/ml). Conclusions: This analysis, despite inevitable inherent limitations, introduces several clinical implications. First, median 25-OHD-dependent PTH levels revealed no threshold above which increasing 25-OHD fails to further suppress PTH. Second, the large number of subjects with 25-OHD deficiency and hyperparathyroidism reinforces the Third International Workshop on Asymptomatic Primary Hyper parathyroidism's recommendations to test for, and replete, vitamin D depletion before considering parathyroidectomy. Third, strong age dependency of the PTH-25-OHD relationship likely reflects the composite effects of age-related decline in calcium absorption and renal function. Finally, this unselected large population database study could guide clinical management of patients based on an age-dependent, PTH-25-OHD continuum.


2020 ◽  
Author(s):  
Abbi R. Hernandez ◽  
Quinten P. Federico ◽  
Sara N. Burke

AbstractDeclining health and cognition are hallmarks of advanced age that reduce both the quality and length of the lifespan. While caloric restriction has been highlighted as a dietary intervention capable of improving the healthspan by restoring metabolic function in late life, time-restricted feeding and changes in dietary macronutrient composition may be more feasible alternatives with similar health outcomes. To investigate the potential of these two interventions, a pilot cohort of fully mature adult rats were placed on a time-restricted feeding regimen of a ketogenic or micronutrient and calorically matched control diet from 8 to 21 months of age. A third group of rats was permitted to eat standard chow ad libitum. At 22 months, all rats were then placed on time-restricted feeding and tested on a biconditional association task. While the data presented here are preliminary (small sample size of 3-4/diet group), additional animals are currently undergoing the feeding regimen, and will be added into the behavioral studies at a later date. For the current data, regardless of dietary composition, time-restricted-fed rats performed significantly better than ad libitum-fed rats. This observation could not be accounted for by differences in motivation, procedural or sensorimotor impairments, indicating that mid-life dietary interventions capable of preventing metabolic impairments may also serve to prevent age-related cognitive decline.


2015 ◽  
Vol 1 (1) ◽  
pp. 12-18 ◽  
Author(s):  
Lindsay C Johnston ◽  
Ruijun Chen ◽  
Travis M Whitfill ◽  
Christie J Bruno ◽  
Orly L Levit ◽  
...  

IntroductionDirect laryngoscopy (DL) and airway intubation are critical for neonatal resuscitation. A challenge in teaching DL is that the instructor cannot assess the learners’ airway view. Videolaryngoscopy (VL), which allows display of a patient's airway on a monitor, enables the instructor to view the airway during the procedure. This pilot study compared deliberate practice using either VL with instruction (I-VL) or traditional DL. We hypothesised that I-VL would improve the efficiency and effectiveness of neonatal intubation (NI) training.MethodsParticipants (students, paediatric interns and neonatal fellows) were randomised to I-VL or DL. Baseline technical skills were assessed using a skills checklist and global skills assessment. Following educational sessions, deliberate practice was performed on mannequins using the Storz C-MAC. With I-VL, the instructor could guide training using a real-time airway monitor view. With DL, feedback was based solely on technique or direct visual confirmation, but the instructor and learner views were not concurrent. During summative assessment, procedural skills checklists were used to evaluate intubation ability on a neonatal airway trainer. The duration of attempts was recorded, and recorded airway views were blindly reviewed for airway grade. ‘Effectiveness’ reflected achievement of the minimum passing score (MPS). ‘Efficiency’ was the duration of training for learners achieving the MPS.Results58 learners were randomised. Baseline demographics were similar. All participants had a significant improvement in knowledge, skills and comfort/confidence following training. There were no significant differences between randomised groups in efficiency or effectiveness, but trends towards improvement in each were noted. Fellows were more likely to achieve ‘competency’ postinstruction compared to non-fellows (p<0.001).ConclusionsThis educational intervention to teach NI increased the learner's knowledge, technical skills and confidence in procedural performance in both groups. I-VL did not improve training effectiveness. The small sample size and participant diversity may have limited findings, and future work is indicated.


2021 ◽  
pp. 112067212110425
Author(s):  
Amar Pujari ◽  
Gunjan Saluja ◽  
Rohan Chawla ◽  
Asha Samdani ◽  
Swati Phuljhele ◽  
...  

Optical coherence tomography angiography (OCTA) is a non-invasive tool to assess the retino-choroidal vasculature in vivo. It tracks the red blood cell movement and maps the vasculature in quick succession. In routine, diabetic retinopathy, age related macular degeneration, central serous chorioretinopathy, and others are commonly being studied to unveil its clinic role. On the other hand, amblyopia is a condition where the visual acuity is subnormal due to non-organic causes in the eye. But the OCTA studies till now have shown variable changes along retino-choroidal vasculature. Hence, to comprehend the existing literature knowledge, a systematic literature search was carried out and the original works describing novel findings in amblyopic eyes on OCTA were included. Upon detailed assessment, firstly, the disturbed vasculature along superficial retinal plexus, deeper retinal plexus, and choroidal plexus were evident in most untreated amblyopic eyes. However, such changes were not uniform, which is due to noted heterogenic patient profile, small sample size, biometric biases, non-uniform algorithms, and other factors. And to note, even in presence of such diverse changes, almost all the authors stated a plausible explanation for their notable changes. Secondly, the utility of OCTA in identifying vascular changes with standard treatments and segregation of visual beneficiaries from non-beneficiaries were possible. Hence, to conclude, OCTA is a valuable tool which can provide valuable useful insights into the amblyopic eyes during pre and post treatment periods. However, to gather more concrete evidence for clinical benefits, systematic, homogenous, and better structured clinical studies are mandated.


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