The effects of robotic assistance on upper limb spatial muscle synergies in healthy people during planar upper-limb training

BackgroundRobotic rehabilitation is a commonly adopted technique used to restore motor functionality of neurological patients. However, despite promising results were achieved, the effects of human-robot interaction on human motor control and the recovery mechanisms induced with robot assistance can be further investigated even on healthy subjects before translating to clinical practice. In this study, we adopt a standard paradigm for upper-limb rehabilitation (a planar device with assistive control) with linear and challenging curvilinear trajectories to investigate the effect of the assistance in human-robot interaction in healthy people.MethodsTen healthy subjects were instructed to perform a large set of radial and curvilinear movements in two interaction modes: 1) free movement (subjects hold the robot handle with no assistance) and 2) assisted movement (with a force tunnel assistance paradigm). Kinematics and EMGs from representative upper-limb muscles were recorded to extract phasic muscle synergies. The free and assisted interaction modes were compared assessing the level of assistance, error, and muscle synergy comparison between the two interaction modes.ResultsIt was found that in free movement error magnitude is higher than with assistance, proving that task complexity required assistance also on healthy controls. Moreover, curvilinear tasks require more assistance than standard radial paths and error is higher. Interestingly, while assistance improved task performance, we found only a slight modification of phasic synergies when comparing assisted and free movement.ConclusionsWe found that on healthy people, the effect of assistance was significant on task performance, but limited on muscle synergies. The findings of this study can find applications for assessing human-robot interaction and to design training to maximize motor recovery

Human Immunodeficiency Virus (HIV)-Antibody Repertoire Estimates Reservoir Size and Time of Antiretroviral Therapy Initiation in Virally Suppressed Perinatally HIV-Infected Children

Different specific antibody responses against 10 HIV-1 viral proteins detected by Western blot, plasma assay on a very small amount of plasma (20 μL) can estimate HIV-DNA size and timing of ART initiation in long-term virally suppressed children

Predictors of faster virological suppression in early treated infants with perinatal HIV from Europe and Thailand The European Pregnancy and Paediatric HIV Cohort Collaboration (EPPICC) and Early-treated Perinatally HIV-infected Individuals: Improving Children's Actual Life with Novel Immunotherapeutic Strategies (EPIICAL) study groups

Objective: To identify predictors of faster time to virological suppression among infants starting combination antiretroviral therapy (cART) early in infancy. Design: Cohort study of infants from Europe and Thailand included in studies participating in the European Pregnancy and Paediatric HIV Cohort Collaboration. Methods: Infants with perinatal HIV starting cART aged less than 6 months with at least 1 viral load measurement within 15 months of cART initiation were included. Multi-variable interval-censored flexible parametric proportional hazards models were used to assess predictors of faster virological suppression, with timing of suppression assumed to lie in the interval between last viral load at least 400 and first viral load less than 400 copies/ml. Results: Of 420 infants, 59% were female and 56% from Central/Western Europe, 26% United Kingdom/Ireland, 15% Eastern Europe and 3% Thailand; 46 and 54% started a boosted protease inhibitor-based or nonnucleoside reverse transcriptase inhibitor-based regimen, respectively. At cART initiation, the median age, CD4(+) % and viral load were 2.9 [interquartile range (IQR): 1.4-4.1] months, 34 (IQR: 24-45)% and 5.5 (IQR: 4.5-6.0) log(10) copies/ml, respectively. Overall, an estimated 89% (95% confidence interval: 86-92%) achieved virological suppression within 12 months of cART start. In multivariable analysis, younger age [adjusted hazard ratio (aHR): 0.84 per month older; P < 0.001], higher CD4(+) % (aHR: 1.11 per 10% higher; P=0.010) and lower log(10) viral load (aHR: 0.85 per log(10) higher; P < 0.001) at cART initiation independently predicted faster virological suppression. Conclusion: We observed a significant independent effect of age at cART initiation, even within a narrow 6 months window from birth. These findings support the earliest feasible cART initiation in infants and suggest that early therapy influences key virological and immunological parameters that could have important consequences for long-term health. Copyright (C) 2019 The Author(s). Published by Wolters Kluwer Health, Inc