Citations

Epidural electrical stimulation (EES) of the spinal cord has been shown to restore function after spinal cord injury (SCI). Characterization of EES-evoked motor responses has provided a basic understanding of spinal sensorimotor network activity related to EES-enabled motor activity of the lower extremities. However, the use of EES-evoked motor responses to guide EES system implantation over the spinal cord and their relation to post-operative EES-enabled function in humans with chronic paralysis attributed to SCI has yet to be described. Herein, we describe the surgical and intraoperative electrophysiological approach used, followed by initial EES-enabled results observed in 2 human subjects with motor complete paralysis who were enrolled in a clinical trial investigating the use of EES to enable motor functions after SCI. The 16-contact electrode array was initially positioned under fluoroscopic guidance. Then, EES-evoked motor responses were recorded from select leg muscles and displayed in real time to determine electrode array proximity to spinal cord regions associated with motor activity of the lower extremities. Acceptable array positioning was determined based on achievement of selective proximal or distal leg muscle activity, as well as bilateral muscle activation. Motor response latencies were not significantly different between intraoperative recordings and post-operative recordings, indicating that array positioning remained stable. Additionally, EES enabled intentional control of step-like activity in both subjects within the first 5 days of testing. These results suggest that the use of EES-evoked motor responses may guide intraoperative positioning of epidural electrodes to target spinal cord circuitry to enable motor functions after SCI.

BackgroundEfforts to promote the cessation of harmful alcohol use are hindered by the affective and physiological components of alcohol withdrawal (AW), which can include life‐threatening seizures. Although previous studies ofAWand relapse have highlighted the detrimental role of stress, little is known about genetic risk factors.MethodsWe conducted a genome‐wide association study ofAWsymptom count in uniformly assessed subjects with histories of seriousAW, followed by additional genotyping in independentAWsubjects.ResultsThe top association signal forAWseverity was in sortilin family neurotrophin receptor geneSORCS2on chromosome 4 (European American meta‐analysisn = 1,478,p = 4.3 × 10−9). There were no genome‐wide significant findings in African Americans (n = 1,231). Bioinformatic analyses were conducted using publicly available high‐throughput transcriptomic and epigenomic data sets, showing that in humansSORCS2is most highly expressed in the nervous system. The identifiedSORCS2risk haplotype is predicted to disrupt a stress hormone‐modulated regulatory element that has tissue‐specific activity in human hippocampus. We used human neural lineage cells to demonstrate in vitro a causal relationship between stress hormone levels andSORCS2expression, and show thatSORCS2levels in culture are increased upon ethanol exposure and withdrawal.ConclusionsTaken together, these findings indicate that the pathophysiology of withdrawal may involve the effects of stress hormones on neurotrophic factor signaling. Further investigation of these pathways could produce new approaches to managing the aversive consequences of abrupt alcohol cessation.

AbstractRecent research has highlighted the importance of the human microbiome in many human disease and health conditions. Most current microbiome association analyses focus on unrelated samples; such methods are not appropriate for analysis of data collected from more advanced study designs such as longitudinal and pedigree studies, where outcomes can be correlated. Ignoring such correlations can sometimes lead to suboptimal results or even possibly biased conclusions. Thus, new methods to handle correlated outcome data in microbiome association studies are needed. In this paper, we propose the correlated sequence kernel association test (CSKAT) to address such correlations using the linear mixed model. Specifically, random effects are used to account for the outcome correlations and a variance component test is used to examine the microbiome effect. Compared to existing genetic association tests for longitudinal and family samples, we implement a correction procedure to better calibrate the null distribution of the score test statistic to accommodate the small sample size nature of data collected from a typical microbiome study. Comprehensive simulation studies are conducted to demonstrate the validity and efficiency of our method, and we show that CSKAT achieves a higher power than existing methods while correctly controlling the Type I error rate. We also apply our method to a microbiome data set collected from a UK twin study to illustrate its potential usefulness. A free implementation of our method in R software is available at https://github.com/jchen1981/SSKAT.

Introduction This manuscript describes data from an original study, simulating a tele-glaucoma programme in an established clinic practice with an interdisciplinary team. This is a ‘real life’ trial of a telemedicine approach to see a follow-up patient. The goal is to evaluate the accuracy of such a programme to detect worsening and/or unstable disease. Such a programme is attractive since in-clinic time could be reduced for both the patient and provider. This study evaluates agreement between in-person and remote assessment of glaucoma progression. Methods A total of 200 adult glaucoma patients were enrolled at a single institution. The in-person assessment by an optometrist or glaucoma specialist at time of enrolment was used as the gold standard for defining progression. Collated clinical data were then reviewed by four masked providers who classified glaucoma as progression or non-progression in each eye by comparing data from enrolment visit to data from the visit immediately prior to enrolment. Agreement of glaucoma progression between the masked observer and the in-person assessment was determined using Kappa statistics. Intra-observer agreement was calculated using Kappa to compare in-person to remote assessment when both assessments were performed by the same provider ( n = 279 eyes). Results A total of 399 eyes in 200 subjects were analysed. Agreement between in-person versus remote assessment for the determination of glaucoma progression was 63%, 62%, 69% and 68% for each reader 1–4 (kappa values = 0.19, 0.20, 0.35 and 0.33, respectively). For intra-observer agreement, reader 1 agreed with their own in-person assessment for 65% of visits (kappa = 0.18). Discussion Intra-observer agreement was similar to the agreement for each provider who did not see the patient in person. This similarity suggests that telemedicine may be equally effective at identifying glaucomatous disease progression, regardless of whether the same provider performed both in-clinic and remote assessments. However, fair agreement levels highlight a limitation of using only telemedicine data to determine progression compared with clinical detail available during in-patient assessment.

BACKGROUNDA prior practice survey revealed variations in the management of patients with sickle cell disease (SCD) and stressed the need for comprehensive guidelines. Here we discuss: 1) common indications for red blood cell exchange (RCE), 2) options for access, 3) how to prepare the red blood cells (RBCs) to be used for RCE, 4) target hemoglobin (Hb) and/or hematocrit (Hct) and HbS level, 5) RBC depletion/RCE, and 6) some complications that may ensue.STUDY DESIGN AND METHODSFifteen physicians actively practicing apheresis from 14 institutions representing different areas within the United States discussed how they manage RCE for patients with SCD.RESULTSSimple transfusion is recommended to treat symptomatic anemia with Hb level of less than 9 g/dL. RCE is indicated to prevent or treat complications arising from the presence of HbS. The most important goals are reduction of HbS while also preventing hyperviscosity. The usual goals are a target HbS level of not more than 30% and Hct level of less than 30%.CONCLUSIONAlthough a consensus as to protocol details may not be possible, there are areas of agreement in the management of these patients, for example, that it is optimal to avoid hyperviscosity and iron overload, that a target Hb S level in the range of 30% is generally desirable, and that RCE as an acute treatment for pain crisis in the absence of other acute or chronic conditions is ordinarily discouraged.