Cytokine balance as a diagnostic marker of inflammation in experimental purulent lesions of soft tissues

Inflammatory process is at the heart of artificial (artificial) purulent-inflammatory diseases of soft tissues (APDST), which may lead to the development of phlegmon and abscesses at the site of invasion within a three-day period. The study of the cytokine status of rats with APDST allows us to evaluate the dynamics of inflammation markers and assess the peculiarities of the pathological course in artificial model of inflammation. The experiment was carried out on 126 white Wistar rats divided into 3 groups: (1) the main group (n = 57), where the laboratory model of APDST was used; (2) a comparison group (n = 58), in which the rats were injected with a mixture of opportunistic bacterial strains isolated from pure cultures of human oral fluid, i.e., S. epidermidis, S. mitis, S. salivarius at the titer of 9lg (CFU) per 1 ml injected together with a mixture of 2.5% hydrocortisone acetate emulsion (20 mg per 100 g of animal body weight), and dexamethasone solution at the dose of 0.5 mg; (3) control group (n = 11), where the animals were injected with 0.9% sodium chloride solution in a volume of 0.3 ml, together with a mixture of 2.5% hydrocortisone acetate emulsion at the rate of 20 mg per 100 g of body weight, and dexamethasone solution at the dose of 0.5 mg. Blood cells were studied using the Mindray DC-2800 Vet Auto Hematology Analyzer automated rat blood test system. The dynamics of pro-inflammatory cytokines: tumor necrosis factor (TNF), interleukin-1β (IL-1β), interleukin-6 (IL-6), antiinflammatory cytokines: interleukin-4 (IL-4), interleukin-10 (IL-10) was assessed by enzyme immunoassay. To predict the course of inflammation towards complications, or resolution of the inflammatory process, the ratio of pro-inflammatory to anti-inflammatory cytokines was used, with normal ratio considered an estimated average of the cytokine ratio for the control group. When analyzing results of this experimental study, the nature of cellular inflammatory response was assessed in dynamics, and its relationship with inflammation markers was determined. All animals of the main group developed soft tissue phlegmon within 3 to 7 days from the beginning of the experiment, and their mortality rate was 100%. In comparison group, the abscesses developed in 82.8% of cases on the day 12 to 15 from the start of the experiment, without any deaths observed. The ratio of pro- and anti-inflammatory cytokines in the main group increased 8-fold already by the end of the 1st day, the comparison group was characterized by the absence of significant differences from the control group. The highest levels of pro-inflammatory cytokines were recorded in the main experimental group on the days 12 to 15

Human-machine interface for two-dimensional steering control with the auricular muscles

Human-machine interfaces (HMIs) can be used to decode a user's motor intention to control an external device. People that suffer from motor disabilities, such as spinal cord injury, can benefit from the uses of these interfaces. While many solutions can be found in this direction, there is still room for improvement both from a decoding, hardware, and subject-motor learning perspective. Here we show, in a series of experiments with non-disabled participants, a novel decoding and training paradigm allowing naïve participants to use their auricular muscles (AM) to control two degrees of freedom with a virtual cursor. AMs are particularly interesting because they are vestigial muscles and are often preserved after neurological diseases. Our method relies on the use of surface electromyographic records and the use of contraction levels of both AMs to modulate the velocity and direction of a cursor in a two-dimensional paradigm. We used a locking mechanism to fix the current position of each axis separately to enable the user to stop the cursor at a certain location. A five-session training procedure (20–30 min per session) with a 2D center-out task was performed by five volunteers. All participants increased their success rate (Initial: 52.78 ± 5.56%; Final: 72.22 ± 6.67%; median ± median absolute deviation) and their trajectory performances throughout the training. We implemented a dual task with visual distractors to assess the mental challenge of controlling while executing another task; our results suggest that the participants could perform the task in cognitively demanding conditions (success rate of 66.67 ± 5.56%). Finally, using the Nasa Task Load Index questionnaire, we found that participants reported lower mental demand and effort in the last two sessions. To summarize, all subjects could learn to control the movement of a cursor with two degrees of freedom using their AM, with a low impact on the cognitive load. Our study is a first step in developing AM-based decoders for HMIs for people with motor disabilities, such as spinal cord injury

A modular strategy for next-generation upper-limb sensory-motor neuroprostheses

Neuroprosthetics is a discipline that aims at restoring lost functions to people affected by a variety of neurological disorders or neurotraumatic lesions. It combines the expertise of computer science and electrical, mechanical, and micro/nanotechnology with cellular, molecular, and systems neuroscience. Rapid breakthroughs in the field during the past decade have brought the hope that neuroprostheses can soon become a clinical reality, in particular—as we will detail in this review—for the restoration of hand functions. We argue that any neuroprosthesis relies on a set of hardware and algorithmic building elements that we call the neurotechnological modules (NTs) used for motor decoding, movement restoration, or sensory feedback. We will show how the modular approach is already present in current neuroprosthetic solutions and how we can further exploit it to imagine the next generation of neuroprosthetics for sensory-motor restoration

Gait pattern prediction via bilateral neural ensemble recordings in motor cortex in rats.

We are interested in developing and building an experimental system for controlling a quadruped robot with a brain-derived signal of a rat. We recorded large ensembles of neurones in left M1 and right M1 and S1 using chronically implanted multi-electrodes arrays (up to 96 electrodes) in rats. The interpretation of such signals has proceeded to an advanced stage in animal experiments. Recently, this highly documented and efficient technology has given many concrete results and has opened new perspectives in the neuroprosthetics field. In our project we correlated motor area signals with the speed of a rat when walking on a treadmill. In parallel, we have performed an accurate analysis of rats kinematics. We performed the gait analysis thanks to an ad hoc motion capture system. We are able to reconstruct a 19 DOF (degree of freedom) simulated model of the rat skeleton for different speeds and different gaits patterns (walk to trot). We can now predict any of the 19 joint angles positions given brain derived signal. Preliminary results of our models suggest that with a high dimensional signal from cortical activity we can predict the actual gait patterns well (up to R2 = 0.64)

Before Disaster Strikes: A Pilot Intervention to Improve Pediatric Trainees\u27 Knowledge of Disaster Medicine

OBJECTIVE: Because training in pediatric disaster medicine (PDM) is neither required nor standardized for pediatric residents, we designed and integrated a PDM course into the curriculum of a pediatric residency program and assessed if participation increased participants\u27 knowledge of managing disaster victims. METHODS: We adapted and incorporated a previously studied PDM course into a small-sized pediatric residency program. The curriculum consisted of didactic lectures and experiential learning via simulation with structured debriefing. With IRB approval, the authors conducted a longitudinal series of pretests and posttests to assess knowledge and perceptions. RESULTS: Sixteen eligible residents completed the intervention. Before the course, none of the residents reported experience treating disaster victims. Pairwise comparison of scores revealed a 35% improvement in scores immediately after completing the course (95% confidence interval, 22.73%-47.26%; P \u3c 0.001) and a 23.73% improvement 2 months later (95% confidence interval, 7.12%-40.34%; P \u3c 0.01). CONCLUSIONS: Residents who completed this course increased their knowledge of PDM with moderate retention of knowledge gained. There was a significant increase in perceived ability to manage patients in a disaster situation after this educational intervention and the residents\u27 confidence was preserved 2 months later. This PDM course may be used in future formulation of a standardized curriculum

Restoration of natural thermal sensation in upper-limb amputees

The use of hands for gathering rich sensory information is essential for proper interaction with the environment; therefore, the restoration of sensation is critical for reestablishing the sense of embodiment in hand amputees. Here, we show that a noninvasive wearable device can be used to provide thermal sensations on amputees’ phantom hands. The device delivers thermal stimuli to specific regions of skin on their residual limb. These sensations were phenomenologically similar to those on the intact limbs and were stable over time. Using the device, the subjects could successfully exploit the thermal phantom hand maps to detect and discriminate different thermal stimuli. The use of a wearable device that provides thermal sensation can increase the sense of embodiment and improve life quality in hand amputees

Non-invasive, Brain-controlled Functional Electrical Stimulation for Locomotion Rehabilitation in Individuals with Paraplegia

Spinal cord injury (SCI) impairs the flow of sensory and motor signals between the brain and the areas of the body located below the lesion level. Here, we describe a neurorehabilitation setup combining several approaches that were shown to have a positive effect in patients with SCI: gait training by means of non-invasive, surface functional electrical stimulation (sFES) of the lower-limbs, proprioceptive and tactile feedback, balance control through overground walking and cue-based decoding of cortical motor commands using a brain-machine interface (BMI). The central component of this new approach was the development of a novel muscle stimulation paradigm for step generation using 16 sFES channels taking all sub-phases of physiological gait into account. We also developed a new BMI protocol to identify left and right leg motor imagery that was used to trigger an sFES-generated step movement. Our system was tested and validated with two patients with chronic paraplegia. These patients were able to walk safely with 65-70% body weight support, accumulating a total of 4,580 steps with this setup. We observed cardiovascular improvements and less dependency on walking assistance, but also partial neurological recovery in both patients, with substantial rates of motor improvement for one of them

Exoskeletons as Mechatronic Design Example

Exoskeletons are a perfect example of a mechatronics product. They illustrate the close integration and interdependence of mechanical design, drive train, sensors, control strategy and user interface. Recent developments of our lab will be discussed in detail. Application examples include paraplegics, amputees, muscular dystrophy patients. The motivations of the users exoskeletons are as diverse as sporting challenge, life quality improvement for daily living, rehabilitation and social integration. Links to Cognitive Neurosciences will also be briefly discussed