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Introduction: Muscle activity patterns in the residual arm are systematically present during phantom hand movements (PHM) in transhumeral amputees. However, their characteristics have not been directly investigated yet, leaving their neurophysiological origin poorly understood. This study pioneers a neurophysiological perspective in examining PHM-related muscle activity patterns by characterizing and comparing them with those in the arm, forearm, and hand muscles of control participants executing intact hand movements (IHM) of similar types., Methods: To enable rigorous comparison, we developed meta-variables independent of electrode placement, quantifying the phasic profile of recorded surface EMG signals and the specificity of their patterns across electrode sites and movement types., Results: Similar to the forearm and hand muscles during IHM, each signal recorded from the residual upper arm during PHM displays a phasic profile, synchronized with the onset and offset of each movement repetition. Furthermore, the PHM-related patterns of phasic muscle activity are specific not only to the type of movement but also to the electrode site, even within the same upper arm muscle, while these muscles exhibit homogeneous activities in intact arms., Discussion: Our results suggest the existence of peripheral reorganization, eventually leading to the emergence of independently controlled muscular sub-volumes. This reorganization potentially occurs through the sprouting of severed axons and the recapture of muscle fibers in the residual limb. Further research is imperative to comprehend this mechanism and its relationship with PHM, holding significant implications for the rehabilitation process and myoelectric prosthesis control., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chateaux, Rossel, Vérité, Nicol, Touillet, Paysant, Jarrassé and De Graaf.)

Purpose: Laparoscopic surgery has improved outcomes in abdominal surgery, but presents kinematic restrictions for surgeons. Robotic comanipulation with adaptative damping has been investigated in simple laparoscopic tasks. The present protocol aimed to determine the contribution of adaptive damping in complex bimanual tasks approaching clinical setting., Methods: Fourteen residents in general surgery performed three exercises, and for each three repetitions without (classic repetitions) and three with robotic assistance (robotic repetitions) in a randomised order. The exercises chosen were trajectory, modified Pea on a Peg and intracorporeal suture. Task performance, gesture performance, workload and impression were measured. Also, a semi-directed interview was performed to collect the participants' feeling about companipulated robots and their potential application in clinical practice., Results: Adaptative damping assistance did not impact task performance, but allowed an economy of movement in the non-dominant hand during suture exercise (distance 916 ± 500 mm in classic vs. 563 ± 261 mm in robotic, p < 0.001). Perceived workload (p = 0.12) and user's impression were not different between classic and robotic repetitions, except novelty (p < 0.001). Participants' interviews revealed their interest for the robotic devices, particularly the gravity compensation, and were ready to use the adaptative damping provided an intermittent use, for example to dissect dangerous areas., Conclusion: Adaptative damping applied by comanipulated robots does not influence the performance of the task, but improves the performance of the gesture itself, particularly for the non-dominant hand, and during the realisation of a complex task like suturing. For residents in digestive surgery, this assistance does increase workload, and they would use this help in the operating room under certain conditions., (© 2024. CARS.)

Purpose: Laparoscopic surgery has demonstrated various advantages for the patients' care, but also presents some difficulties for the surgeons, such as kinematic restrictions. Robotic comanipulation, in which control of instruments is shared between the robot and the surgeon, can provide adaptative damping assistance which allows stabilisation of movements. The objective of the present study was to determine the contribution of this assistance on a bimanual laparoscopic task., Methods: Adaptative damping was studied on Peg Transfer task, performed by eighteen surgery-naive subjects. This exercise was repeated seven times without (Classic repetitions) and seven times with comanipulated robots (Robot repetitions), in a randomised order. We measured task performance, using Peg Transfer score; gesture performance, using hand oscillations and travelled distance; eye-tracking movements as an indicator of emergence of expertise. Participants' perceived workload was assessed by NASA TLX questionnaire, and difference in impression between the two conditions by UEQ questionnaire., Results: Adaptative damping improved gesture performance (oscillations F(1,17) = 23.473, p < 0.001, η 2  = 0.580), with a statistically significant simple effect on the tool oscillation for both non-dominant (p < 0.001) and dominant hands (p = 0.005), without influencing task performance (mean Peg Transfer score t(17) = 0.920, p = 0.382, d = 0.29), but deteriorating eye-tracking movements associated with emergence of expertise (mean fixation rate per second F(1,17) = 6.318, p = 0.022, η 2  = 0.271), at the cost of a high perceived workload (NASA TLX score 59.78/100)., Conclusion: Assistance by adaptative damping applied by comanipulated robots improved gesture performance during a laparoscopic bimanual task, without impacting task's performance without allowing the emergence of comportments associated with an expertise, and at the cost of a high perceived workload. Further research should investigate this assistance on more precise and clinical tasks performed by professionals., (© 2022. CARS.)

CD95 is a death receptor that can promote oncogenesis through molecular mechanisms that are not fully elucidated. Although the mature CD95 membrane receptor is considered to start with the arginine at position 17 after elimination of the signal peptide, this receptor can also be cleaved by MMP7 upstream of its leucine at position 37. This post-translational modification occurs in cancer cells but also in normal cells such as peripheral blood leukocytes. The non-cleaved CD95 amino-terminal region consists in a disordered domain and its in silico reconstitution suggests that it might contribute to receptor aggregation and thereby, regulate the downstream death signaling pathways. In agreement with this molecular modeling analysis, the comparison of CD95-deficient cells reconstituted with full-length or N-terminally truncated CD95 reveals that the loss of the amino-terminal region of CD95 impairs the initial steps of the apoptotic signal while favoring the induction of pro-survival signals, including the PI3K and MAPK pathways., (© 2022. The Author(s).)

(1) Background: The aim was to describe the rate and outcomes of cystoid macular edema (CME) after pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD) and to identify risk factors and imaging characteristics. (2) Methods: A retrospective consecutive case study was conducted over a 5-year period among adult patients who underwent PPV for primary RRD repair. The main outcome measure was the rate of CME at 12 months following PPV. (3) Results: Overall, 493 eyes were included. The CME rate was 28% (93 patients) at 12 months. In multivariate analysis, eyes with worse presenting visual acuity (VA) (odds ratio [OR], 1.55; 95% CI, 1.07-2.25; p = 0.02) and grade C proliferative vitreoretinopathy (PVR) (OR, 2.88; 95% CI, 1.04-8.16; p = 0.04) were more at risk of developing CME 1 year after PPV. Endolaser retinopexy was associated with a greater risk of CME than cryotherapy retinopexy (OR, 3.06; 95% CI, 1.33-7.84; p = 0.01). Eyes undergoing cataract surgery within 6 months of the initial RRD repair were more likely to develop CME at 12 months (OR, 1.96; 95% CI, 1.06-3.63; p = 0.03). (4) Conclusions: CME is a common complication after PPV for primary RRD repair. Eyes with worse presenting VA, severe PVR at initial presentation, endolaser retinopexy, and cataract surgery within 6 months of initial RRD repair were risk factors for postoperative CME at 12 months.

Exoskeletons are robots that closely interact with humans and that are increasingly used for different purposes, such as rehabilitation, assistance in the activities of daily living (ADLs), performance augmentation or as haptic devices. In the last few decades, the research activity on these robots has grown exponentially, and sensors and actuation technologies are two fundamental research themes for their development. In this review, an in-depth study of the works related to exoskeletons and specifically to these two main aspects is carried out. A preliminary phase investigates the temporal distribution of scientific publications to capture the interest in studying and developing novel ideas, methods or solutions for exoskeleton design, actuation and sensors. The distribution of the works is also analyzed with respect to the device purpose, body part to which the device is dedicated, operation mode and design methods. Subsequently, actuation and sensing solutions for the exoskeletons described by the studies in literature are analyzed in detail, highlighting the main trends in their development and spread. The results are presented with a schematic approach, and cross analyses among taxonomies are also proposed to emphasize emerging peculiarities.

Upright posture control and gait are essential for achieving autonomous daily living activities. Postural control of upright posture relies, among others, on the integration of various sensory information. In this context, light touch (LT) and light grip (LG) of a stationary object provide an additional haptic sensory input that helps to reduce postural sway. When LG was studied through the grasp of a cane, the sensory role of this assistive tool was often limited to a mediation interface. Its role was restricted to transmit the interaction forces between its tip and the ground to the hand. While most studies involve participants standing in an unstable way, such as the tandem stance, in this paper we study LG from a different perspective. We attached a handle of a cane firmly to a stationary support. Thus, we can focus on the role of the hand receptors in the LG mechanism. LG condition was ensured through the tactile information gathered by FSR sensors placed on the handle surface. Moreover, participants involved in our study stood in a usual way. The study involved twelve participants in an experiment composed of two conditions: standing relaxed while lightly gripping an equipped handle attached to the ground, and standing in the same way without gripping the handle. Spatial and frequency analyses confirmed the results reported in the literature with other approaches.

Lightly touching an earth-fixed external surface with the forefinger provides somatosensory information that reduces the center of pressure (CoP) oscillations. If this surface were to move slowly, the central nervous system (CNS) would misinterpret its movement as body self-motion, and involuntary compensatory sway responses would appear, resulting in a significant coupling between finger and CoP motions. We designed a forefinger moving light-touch biofeedback based on this finding, which controls the surface velocity to drive the CoP towards a target position. Here, we investigate this biofeedback resistance to cognitive processes. In addition to a baseline, the experimental protocol includes four main conditions. In the first, participants were utterly naive about the feedback. Then, they received additional reliable sensory information. The third condition ensured their full awareness of the external nature of the surface motion. Finally, the experimenter notified them that the external motion drives their balance and asked them to reject its influence. Our investigation shows that despite the robustness of the proposed biofeedback, light-touch remains penetrable by cognitive processes. For participants to dramatically reduce the existing coupling between the finger and CoP motions, they should be aware of the external motion, how it impacts sway, and actively reject its influence. The main implication of our findings is that light-touch exhibits the same cognitive flexibility as vision when artificially stimulated. This could be interpreted as a defense mechanism to re-weight these two sensory inputs in a moving environment., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The adaptor SHARPIN composes, together with the E3 ligases HOIP and HOIL1, the linear ubiquitin chain assembly complex (LUBAC). This enzymatic complex catalyzes and stamps atypical linear ubiquitin chains onto substrates to modify their fate and has been linked to the regulation of the NF-κB pathway downstream of most immunoreceptors, inflammation, and cell death. However, how this signaling complex is regulated is not fully understood. Here, we report that a portion of SHARPIN is constitutively phosphorylated on the serine at position 165 in lymphoblastoid cells and can be further induced following T cell receptor stimulation. Analysis of a phosphorylation-resistant mutant of SHARPIN revealed that this mark controls the linear ubiquitination of the NF-κB regulator NEMO and allows the optimal activation of NF-κB in response to TNFα. These results identify an additional layer of regulation of the LUBAC and unveil potential strategies to modulate its action., Competing Interests: The authors declare no competing interests., (© 2020 The Author(s).)

Background: Coupling between postural sway and fingertip displacement has been observed in individuals lightly touching a moving surface. This can be attributed to the central nervous system (CNS) misinterpreting surface motion as self-motion, evoking a compensatory sway response., Research Question: Does baseline postural state influence the correct perception of haptic object motion?, Methods: Motion perception detection thresholds of index finger displacement at 1 mm s -1 velocity during light touch were determined for three postural conditions: standing with eyes open (EO) and closed (EC), and sitting with eyes closed. For the standing condition with eyes shut, displacement thresholds were measured using three velocities (1, 2 and 4 mm s -1 )., Results: Postural condition had a large influence on motion perception, with a reduction in displacement threshold from 12 → 6 → 2 mm during the transition from standing EC → standing EO → sitting EC. A systematic decrease in displacement perception threshold was observed with increasing velocity. This tends to suggest that the increase of the touched object velocity may help overcoming the misinterpretation., Significance: These results suggest that the ability to disambiguate self motion from haptic motion is enhanced during stable postures, and when stimulus velocity is high. Our findings may help to understand the mechanisms underlying the coupling between surface movements and postural sway, reported in the literature., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We report the case of a 32-year-old man who developed acute psychiatric disorders after repeated intravenous injections of methylphenidate. The behavioural disorders with extreme psychomotor restlessness and delirious syndrome have resolved within 24hours. The available data highlight the fact that the prescriptions of methylphenidate, an amphetamine-like substance, are constantly increasing in Europe and Northern America. The potential of abuse and addiction to this drug, which is growingly misused, is now clearly established. The medical professionals should be cautious and attentive to the risk of misuse of this drug., (Copyright © 2016 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Background and Objectives: The Vel blood group antigen is a poorly characterized high-prevalence antigen. Until now, anti-Vel antibodies have been observed in only alloimmunized Vel-negative individuals. In this study, we aimed to establish a human hybridoma cell line secreting the first anti-Vel monoclonal antibody (mAb), clone SpG213Dc., Materials and Methods: Peripheral blood lymphocytes from a French Vel-negative woman with anti-Vel in her plasma were transformed with Epstein-Barr virus and then hybridized with the myeloma cell line Sp2/O-Ag14 using the polyethylene glycol (PEG) method. A specific anti-Vel mAb was successfully produced and was extensively characterized by serological, flow cytometry and Western blot analyses., Results: One human anti-Vel-secreting clone was produced and the secreted anti-Vel mAb (SpG213Dc) was examined. The specificity of the SpG213Dc mAb was assessed by its reactivity against a panel of nine genotyped RBCs including, respectively, three Vel-negative and six Vel-positive (three wild-type homozygous and three heterozygous) samples using flow cytometry method. Vel-positive RBCs were specifically stained and were subsequently used to perform Western blot and immunoprecipitation analysis of the Vel antigen., Conclusion: Serological characterization of the new monoclonal anti-Vel SpG213Dc showed a heterogeneous level of expression of the Vel antigen on the different RBCs. Our results suggest that the mAb SpG213Dc can be reliably used as a blood grouping reagent, thus allowing the mass-scale phenotyping of blood donors to strengthen rare blood banks with Vel-negative RBC units., (© 2015 International Society of Blood Transfusion.)

Postural control rehabilitation may benefit from the use of smart devices providing biofeedback. This approach consists of increasing the patients perception of their postural state. Namely, postural state is monitored and fed back in real time to the patients through one or more sensory channels. This allows implementing rehabilitation exercises where the patients control their posture with the help of additional sensory inputs. In this paper, a closed loop control of the Center-Of-Pressure (CoP) based on kinesthetic feedback is proposed as a new form of biofeedback. The motion of a one Degree of Freedom (DoF) translational device, lightly touched by the patient's forefinger, is servoed to the patient's CoP position extracted from the measurements of a force plate on which he/she stands. As a result, the patient's CoP can be controllably displaced. A first set of experiments is used to prove the feasibility of this closed-loop control under ideal conditions favoring the perception of the kinesthetic feedback, while the subject is totally unaware of the context. A second set of experiments is then proposed to evaluate the robustness of this approach under experimental conditions that are more realistic with regards to the clinical context of a rehabilitation program involving biofeedback-based exercises.

We compared the activities of thyroid-stimulating antibodies (TSAb) as measured with two cell lines (JP26 and JP26/26) transfected with cloned human thyrotropin (TSH) receptor and the values for TSAb measured on human thyrocytes cultures. Sera were obtained from patients with Graves' disease, before, during and after therapy with carbimazole (1-methyl-2-thio-3-carbethoxyimidazole). The activities of TSAb performed with the three assays correlated significantly. The TSAb technique using JP26/26 cells was as sensitive as the method performed on human thyrocyte cultures since positive TSAb values were found in 45 out of 47 (95.7%) newly diagnosed patients, in 100% of patients who relapsed after drug withdrawal and in none in remission. When the JP26 cell line was used, sensitivity decreased as the detection rate was only 53.2 and 55.5% before treatment and in case of relapse, respectively. The TSH receptors analysis showed a receptor density two times higher for JP26/26 than for JP26. JP26/26 cells provide similar diagnostic information on human thyrocytes in patients with Graves' disease. Moreover with these cells, the procedure for cell culture is less cumbersome and precision is better. However, rigorous culture conditions are required to maintain TSH receptor expression in transfected cells.

The aim of this study was to investigate the frequencies of clinical diabetes and humoral markers of anti-pancreatic autoimmunity in a homogeneous population of 600 Caucasian patients with recently diagnosed Graves' disease (GD), in order to characterize the specific features of this group of endocrine patients among subjects at risk of diabetes. Ten were already diabetic at GD diagnosis. Among the 590 non-diabetic patients, 29 had islet cell antibodies (ICA), including 15 with low titre ICA and only 1 ICA-positive subject with a familial history of diabetes. Twenty-four patients had insulin autoantibodies, including three in association with ICA. Glutamic acid decarboxylase (GAD)/64 kDa antibodies were found in 16 of the 150 tested sera, including 13 of the 29 ICA-positive sera. Four ICA-positive patients displayed 37/40 kDa antibodies, including three in association with GAD/64 kDa antibodies. During follow-up, one of the ICA-positive patients developed insulin-dependent diabetes, 14 years after the GD diagnosis. To summarize, this anti-pancreatic autoimmunity study was focused on a large but specific and homogeneous group of subjects at risk for diabetes: recently diagnosed GD patients. This population was characterized by a high prevalence of GAD/64 kDa antibodies but also by a low frequency of evolution towards diabetes and the slowness of the process which could be due to the fact that only a minority of subjects possessed a sufficient combination of anti-pancreatic markers at the same time.