Interactive computation and visualization of deep brain stimulation effects using Duality

Deep brain stimulation (DBS) is an established treatment for movement disorders such as Parkinson's disease or essential tremor. Currently, the selection of optimal stimulation settings is performed by iteratively adjusting the stimulation parameters and is a time consuming procedure that requires multiple clinic visits of several hours. Recently, computational models to predict and visualize the effect of DBS have been developed with the goal to simplify and accelerate this procedure by providing visual guidance and such models have been made available also on mobile devices. However, currently available visualization software still either lacks mobility, i.e., it is running on desktop computers and not easily available in clinical praxis, or flexibility, as the simulations that are visualized on mobile devices have to be precomputed. The goal of the pipeline presented in this paper is to close this gap: Using Duality, a newly developed software for the interactive visualization of simulation results, we implemented a pipeline that allows to compute DBS simulations in near-real time and instantaneously visualize the result on a tablet computer. Therefore, a client-server setup is used, so that the visualization and user interaction occur on the tablet computer, while the computations are carried out on a remote server. We present two examples for the use of Duality, one for postoperative programming and one for the planning of DBS surgery in a pre- or intraoperative setting. We carry out a performance analysis and present the results of a case study in which the pipeline for postoperative programming was applied.

0922 Nightly Associations Between Pre-Bedtime Activity, Actigraphic Light, and Sleep in Children With ASD and Insomnia

Introduction

Approximately two thirds of children with Autism Spectrum Disorder (ASD) suffer from chronic insomnia. Current behavioral interventions for insomnia in children with ASD use sleep hygiene guidelines to educate parents and their children regarding sleep promoting habits. However, the relationship between pre-bedtime physical activity/light and sleep is understudied in ASD. The current study examined daily associations between pre-bedtime actigraphically assessed activity/light levels and objective/subjective sleep outcomes in children with ASD and insomnia.

Methods

Thirty children (Mage=8.5 yrs, SD=1.78 yrs) with comorbid ASD and insomnia completed 14 days of actigraphy measuring ambient white light intensity and activity levels every 30 seconds. Validated sleep scoring algorithms (in Actiware V. 6.0.9) estimated objective sleep onset latency (SOL), total sleep time (TST), wake time after sleep onset (WASO), and average activity/light levels 30, 60, and 120 mins prior to bedtime. Additionally, average activity/light levels 120-240, and 240-360 mins prior to bedtime were computed. Children also completed 14 daily sleep diaries (with parental assistance) measuring subjective reports of the same sleep parameters. Associations between daily estimations of pre-bedtime activity levels, light, and nighttime objective and subjective sleep were examined through multilevel modelling. Bonferroni corrections were performed to account for multiple comparisons.

Results

After Bonferroni corrections (p<.025 significance level), greater activity within 30 minutes (B=0.0465, p=.0093) and 60 minutes (B=0.0681, p=.0005) of bedtime were associated with longer subjective SOL. Pre-bedtime light exposure was not a significant predictor of sleep outcomes.

Conclusion

Results suggest that in general, variations in daily pre-bedtime activity, but not light, are associated with worse nightly subjective SOL in children with ASD and insomnia. Findings support that sleep hygiene recommendations in children with ASD include avoidance of higher levels of pre-sleep physical activity. Prospective studies examining temporal causal relationships between pre-bedtime activity and sleep in ASD are warranted.

Support

Research was supported by a University of Missouri Research Board award (McCrae, PI; Mazurek, Co-PI). Data collected as part of clinical trial NCT02755051 Targeting Sleep in Kids with Autism Spectrum Disorder at the University of Missouri (PI: McCrae).

Hepcidin Status at 2 Months in Infants Fed Breast Milk Compared with Formula

INTRODUCTION

The basis for the superior absorption of iron from breast milk compared with infant formulas is unclear. The hormone hepcidin downregulates dietary iron absorption. Hepcidin production increases with increased body iron status (reflected in serum ferritin levels). We hypothesized that serum hepcidin levels are suppressed relative to iron status in infants fed breast milk compared with formula.

METHODS

Subjects were healthy infants presenting for routine 2-month clinic visit and strictly fed either breast milk or standard infant formula. Urinary hepcidin and ferritin levels (reflective of serum levels) were analyzed and compared across the breast milk- and formula-fed groups. The relationship between urinary hepcidin and ferritin levels within each group was analyzed by linear regression.

RESULTS

Twenty-four subjects were enrolled in each group. The median urinary hepcidin level in the group fed breast milk was lower than in formula (130 vs. 359 ng hepcidin/mg creatinine, p < 0.05). However, the median ferritin levels were similar (2.1 vs. 1.9 ng/mL). Within each group, urinary hepcidin correlated with urinary ferritin (r = 0.5, p < 0.05 for each group); however, the slope of the regression line was lower in the group fed breast milk compared with formula (p < 0.005).

CONCLUSION

Despite similar urinary ferritin levels, urinary hepcidin levels are lower at 2 months in infants fed breast milk compared with infants fed formula. Hepcidin levels correlate with iron status in each group; however, this relationship is relatively dampened in infants fed breast milk. We speculate that relatively lower infant hepcidin contributes to the superior efficiency of iron absorption from breast milk.

Effect of calcitriol on serum hepcidin in individuals with chronic kidney disease: a randomized controlled trial

Background

Anemia is highly prevalent in chronic kidney disease (CKD). Elevated hepcidin concentrations are an important mediator of disordered iron metabolism, a key mechanism underlying anemia of CKD. Vitamin D was recently shown to reduce serum hepcidin concentrations in healthy individuals. We examined whether treatment with calcitriol reduces serum hepcidin in individuals with CKD.

Methods

A total of 40 participants with stage 3 or 4 CKD (eGFR 15–60 ml/min/1.73m²) were randomized to receive either oral calcitriol 0.5 mcg daily or identically-matched placebo for 6 weeks. The primary outcome variable was change in serum hepcidin concentrations. Secondary outcomes variables included the change in iron parameters, calcium, phosphorus, intact parathyroid hormone and hemoglobin concentrations. Study samples were drawn at baseline, 3 days, 1 week, 4 weeks and 6 weeks after randomization. Repeated measures analysis was used to examine differences in outcome variables over time in the two groups.

Results

There were no significant differences in the baseline characteristics between the placebo and calcitriol arms. Over 6 weeks of follow-up there were no significant differences in the change in serum hepcidin, iron parameters, or hemoglobin between the two groups. Serum calcium and phosphorus significantly increased and PTH significantly decreased after 6 weeks in calcitriol group whereas these analytes did not change in the placebo group.

Conclusion

Calcitriol did not reduce serum hepcidin concentrations among individuals with mild to moderate CKD. Future studies are needed to assess if nutritional forms of vitamin D affect hepcidin concentrations in CKD.

Trial registration

ClinicalTrials.gov Identifier: NCT01988116. Registered: November 4, 2013.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-0823-7) contains supplementary material, which is available to authorized users.

Compliance of acute and long stay geriatric patients with nutritional supplementation

BACKGROUND

Nutritional supplements are prescribed to improve nutritional status, and reduce hospital stays in manourised hospital patients. Clinical benefits are dependant on compliance, the level of which remains unclear.

AIMS

To assess compliance levels with oral nutritional supplementation and determine methods to improve compliance.

METHODS

Compliance was observed over 10 days by measuring total supplements prescribed and weighing wastage remaining after use. Areas for improvement were identified and implemented for 6 months. Specifically, a distinct supplement administration round was established and those patients requiring assistance with supplement consumption were identified with signage above their beds. Compliance was re-assessed in a sub sample of patients.

RESULTS

Thirty seven elderly patients (mean age 85 years; 57% female) prescribed nutritional supplements were studied. Mean compliance was significantly greater in males than females (85.7% vs 74%) and acute wards compared to longstay (89.5% vs. 74.2 Compliance with supplements was significantly greater following intervention (mean 74.2% vs. 93%, p < 0.0001).

CONCLUSION

Compliance with nutritional supplementation is variable among institutionalized geriatric patients. Timing of supplementation dispensation and improving staff vigilance can positively affect compliance.

Universal neonatal hearing screening moving from evidence to practice

Recent technological advances have made feasible universal newborn hearing screening and therefore early detection of permanent childhood hearing impairment. Over the past three years, new information has been published on whether early intervention is beneficial, the possibility of harm arising from newborn screening, and its cost. Dramatic progress has been made in the large scale implementation of universal screening in many parts of the western world.

Employee drug use, demographic characteristics, work reactions, and absenteeism

Employees in a large work organization participated in an investigation of relationships between drug use and absenteeism and tardiness. Specifically, the study investigated the extent to which both self-reported and urine-screened drug use accounted for variance in several types of absenteeism, as well as tardiness, above and beyond that accounted for by demographic and work reaction variables. The results showed that employee drug use accounted for additional statistically significant variance in overall absenteeism and in absenteeism due to injuries and suspensions, as well as days tardy. Implications of these findings for organizational drug testing are discussed.

The role of marketing research in securing a certificate of need for a new renal transplant facility

The authors describe how a negative Certificate of Need decision on the establishment of a new renal transplantation center was reversed by the reintroduction of arguments based on primary data. Specifically, a research project was undertaken to survey attitudes of past and potential patients toward using the new facility. In addition to overturning the negative decision, the data gathered were of significant value to hospital and transplantation facility administrators.

Autosomal dominant familial spastic paraplegia: report of a large New England family

A large New England family with autosomal dominant familial spastic paraplegia is described. In a pedigree of 173 individuals, 71 affected individuals are identified. Seventeen cases examined by the authors are described with regard to the natural history of FSP in this family. A staging system for following progress and planning interventions is proposed. Three illustrative cases are presented. In this family, FSP is found to have a homogeneous clinical course with nearly complete penetrance. Onset occurs at or before 3 years of age with involvement limited to the lower extremities. After the initial onset, no significant progression was noted. Early aggressive habilitative care may result in more functional ambulation.

A hospital team approach with parents of a Down's syndrome infant

This article is a description of a multidisciplinary team approach with parents of a Down's syndrome infant in the obstetrical department of the Royal Victoria Hospital in Montreal. After a brief explanation on the reason why a refinement of this approach became necessary, the authors give an account of the in-service training that was implemented for professionals as well as some comments on parents' initial reactions to the birth of a Down's syndrome child and the role of professionals in these situations. Finally, a "Protocol for management of Down's syndrome infants in hospital" is included in the last part of the article.

Circadian fluctuation of plasma epinephrine in supine humans

Previous studies have demonstrated circadian fluctuations of systemic catecholamines in man. However, methodological differences and conflicting results with epinephrine are apparent. In the present study, plasma and urinary epinephrine and norepinephrine and plasma cortisol were studied in healthy young adult males over 24 hr with 20 min plasma sampling and EEG monitoring of sleep. Plasma epinephrine did not have a circadian variation in supine subjects. Urinary epinephrine levels and small urinary circadian variations were increased by normal posture and activity. Sleep and sleep stage were not associated with different plasma epinephrine levels, and no ultradian fluctuation was observed. Levels of norepinephrine and cortisol were normal. Based on all studies to date, it appears that basal plasma epinephrine has either a very small amplitude or no circadian rhythm, but that changes in posture and activity or the rest/activity cycle may modify this pattern.