Retraining of interjoint arm coordination after stroke using robot-assisted time-independent functional training

We have developed a haptic-based approach for retraining of interjoint coordination following stroke called time-independent functional training (TIFT) and implemented this mode in the ARMin III robotic exoskeleton. The ARMin III robot was developed by Drs. Robert Riener and Tobias Nef at the Swiss Federal Institute of Technology Zurich (Eidgenossische Technische Hochschule Zurich, or ETH Zurich), in Zurich, Switzerland. In the TIFT mode, the robot maintains arm movements within the proper kinematic trajectory via haptic walls at each joint. These arm movements focus training of interjoint coordination with highly intuitive real-time feedback of performance; arm movements advance within the trajectory only if their movement coordination is correct. In initial testing, 37 nondisabled subjects received a single session of learning of a complex pattern. Subjects were randomized to TIFT or visual demonstration or moved along with the robot as it moved though the pattern (time-dependent [TD] training). We examined visual demonstration to separate the effects of action observation on motor learning from the effects of the two haptic guidance methods. During these training trials, TIFT subjects reduced error and interaction forces between the robot and arm, while TD subject performance did not change. All groups showed significant learning of the trajectory during unassisted recall trials, but we observed no difference in learning between groups, possibly because this learning task is dominated by vision. Further testing in stroke populations is warranted.

ZeroG: overground gait and balance training system

A new overground body-weight support system called ZeroG has been developed that allows patients with severe gait impairments to practice gait and balance activities in a safe, controlled manner. The unloading system is capable of providing up to 300 lb of static support and 150 lb of dynamic (or constant force) support using a custom-series elastic actuator. The unloading system is mounted to a driven trolley, which rides along an overhead rail. We evaluated the performance of ZeroG's unloading system, as well as the trolley tracking system, using benchtop and human-subject testing. Average root-mean-square and peak errors in unloading were 2.2 and 7.2 percent, respectively, over the range of forces tested while trolley tracking errors were less than 3 degrees, indicating the system was able to maintain its position above the subject. We believe training with ZeroG will allow patients to practice activities that are critical to achieving functional independence at home and in the community.

Myocardial infarction and post-traumatic stress disorder: frequency, outcome, and atherosclerotic mechanisms

BACKGROUND: Post-traumatic stress disorder (PTSD) may develop in the aftermath of an acute myocardial infarction (MI). Whether PTSD is a risk factor for cardiovascular disease (CVD) is elusive. The biological mechanisms linking PTSD with atherosclerosis are unclear. DESIGN: A critical review of 31 studies in the English language pursuing three aims: (i) to estimate the prevalence of PTSD in post-MI patients; (ii) to investigate the association of PTSD with cardiovascular endpoints; and (iii) to search for low-grade systemic inflammatory changes in PTSD pertinent to atherosclerosis. METHODS: We located studies by PubMed electronic library search and through checking the bibliographies of these sources. RESULTS: The weighted prevalence of PTSD after MI was 14.7% (range 0-25%; a total of 13 studies and 827 post-MI patients). Two studies reported a prospective association between PTSD and an increased risk of cardiovascular readmission in post-MI patients and of cardiovascular mortality in combat veterans, respectively. In a total of 11 studies, patients with PTSD had increased rates of physician-rated and self-reported cardiovascular diseases. Various cytokines and C-reactive protein were investigated in a total of seven studies suggesting that PTSD confers a pro-inflammatory state. CONCLUSIONS: Increasing evidence suggests that PTSD specifically related to MI develops considerably frequently in post-MI patients. More research is needed in larger cohorts applying a population design to substantiate findings suggesting PTSD is an atherogenic risk factor and to understand better the suspected behavioural and biological mechanisms involved.

Human temporal bones versus mechanical model to evaluate three middle ear transducers

A life-size mechanical middle ear model and human temporal bones were used to evaluate three different middle ear transducers for implantable hearing aids: the driving rod transducer (DRT), the floating mass transducer (FMT) or vibrant sound bridge, and the contactless transducer (CLT). Results of the experiments with the mechanical model were within the range of the results for human temporal bones. However, results with the mechanical model showed better reproducibility. The handling of the mechanical model was considerably simpler and less time-consuming. Systematic variations of mounting parameters showed that the angle of the rod has virtually no effect on the output of the DRT, the mass loading on the cable of the FMT has a larger impact on the output than does the tightness of crimping, and the output level of the CLT can be increased by 10 dB by optimizing the mounting parameters.

Estimating the patient's contribution during robot-assisted therapy

Robot-assisted therapy has become increasingly common in neurorehabilitation. Sophisticated controllers have been developed for robots to assist and cooperate with the patient. It is difficult for the patient to judge to what extent the robot contributes to the execution of a movement. Therefore, methods to comprehensively quantify the patient's contribution and provide feedback are of key importance. We developed a method comprehensively to estimate the patient's contribution by combining kinematic measures and the motor assistance applied. Inverse dynamic models of the robot and the passive human arm calculate the required torques to move the robot and the arm and build, together with the recorded motor torque, a metric (in percentage) that represents the patient's contribution to the movement. To evaluate the developed metric, 12 nondisabled subjects and 7 patients with neurological problems simulated instructed movement contributions. The results are compared with a common performance metric. The estimation shows very satisfying results for both groups, even though the arm model used was strongly simplified. Displaying this metric to patients during therapy can potentially motivate them to actively participate in the training.

«The Broken Years»: War Crimes and the laws of war under the impact of the First World War

When the First World War began, the international co-operation of legal academics, which had been a characteristic of the late 19th and early 20th century came to a halt. In the context of the atrocities in Belgium as well as Serbia academics on both sides became involved in the propaganda campaigns of the belligerents on both sides. Not many of them were able to divest themselves. The presentation will claim that as a consequence the time between the First World War and the beginning of the Second can be characterized as «Broken Years» not only in regard to war veterans (Gammage 1974), but also in regard to the international academic discourse on issues of war crimes and the laws of war. This shall be substantiated by a look at academic activities in the interwar period within the International Law Association, the Institut de Droit International, the Interparliamentary Union, the Association Internationale de Droit Pénal and the Internationale Kriminalistische Vereinigung.

Are Selective Serotonin Reuptake Inhibitors Associated With Hepatocellular Carcinoma in Patients With Hepatitis C?

BACKGROUND AND AIMS: Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed for patients with chronic hepatitis C virus (HCV) infection. Research suggests that serotonin promotes the development and growth of hepatocellular carcinoma (HCC). We tested the hypothesis whether exposure to SSRIs is associated with an increased risk of HCC in HCV patients. METHOD: Patients who entered the United States Veterans Affairs (VA) Hepatitis C Clinical Case Registry in 2000 to 2009 were analyzed. During the 8 years of follow-up, 36,192 patients filled at least 1 SSRI prescription. Cases of HCC were identified by diagnosis codes (ICD-9 155.0). Multivariable Cox regression analyses estimated adjusted HCC hazard ratios (HRs) for SSRI-exposed versus SSRI-unexposed subjects and categories of average SSRI doses. RESULTS: The annual incidence of HCC in the VA registry cohort of 109,736 patients was 0.5% and significantly greater in the 8% with cirrhosis at baseline (HR = 5.2; 95% CI, 4.7-5.7). There was no evidence for significant interactions between the effect of SSRI-exposure and cirrhosis. Baseline characteristics of the exposed (n = 36,192) and unexposed (n = 73,544) subjects were similar. The median (interquartile range [IQR]) follow-up period after SSRI-exposure began was 44 (20-74) months with 18 (3-49) months between the first and last prescription. The median average SSRI dose during follow-up expressed as a fraction of initial recommended doses for depression was 0.94 (IQR, 0.5 to 1.3). The risk of HCC was not significantly increased after SSRI exposure (HR = 0.96; 95% CI, 0.87-1.05) or with increasing SSRI doses. CONCLUSIONS: Analysis of a large cohort of HCV patients did not support the hypothesis that SSRIs increase the risk of developing HCC.

Efficacy of motivational enhancement therapy on alcohol use disorders in patients with chronic hepatitis C: a randomized controlled trial

AIMS: To determine the efficacy of motivational enhancement therapy (MET) on alcohol use in patients with the hepatitis C virus (HCV) and an alcohol use disorder (AUD). DESIGN: Randomized, single-blind, controlled trial comparing MET to a control education condition with 6-month follow-up. SETTING: Patients were recruited from hepatitis clinics at the Minneapolis, Minnesota and Portland, Oregon Veterans Affairs Health Care Systems, USA. PARTICIPANTS AND INTERVENTION: Patients with HCV, an AUD and continued alcohol use (n = 139) were randomized to receive either MET (n = 70) or a control education condition (n = 69) over 3 months. MEASUREMENTS: Data were self-reported percentage of days abstinent from alcohol and number of standard alcohol drinks per week 6 months after randomization. FINDINGS: At baseline, subjects in MET had 34.98% days abstinent, which increased to 73.15% at 6 months compared to 34.63 and 59.49% for the control condition. Multi-level models examined changes in alcohol consumption between MET and control groups. Results showed a significant increase in percentage of days abstinent overall (F(1120.4)  = 28.04, P < 0.001) and a significant group × time effect (F(1119.9)  = 5.23, P = 0.024) with the MET group showing a greater increase in percentage of days abstinent at 6 months compared with the education control condition. There were no significant differences between groups for drinks per week. The effect size of the MET intervention was moderate (0.45) for percentage of days abstinent. CONCLUSION: Motivational enhancement therapy (MET) appears to increase the percentage of days abstinent in patients with chronic hepatitis C, alcohol use disorders and ongoing alcohol use. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.