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This paper aims to fabricate a hybrid piezoelectric/triboelectric nanogenerator via fusion deposition modeling as a proof of concept in the wearable device industry. The nanogenerator structure consists of a TPU/ZnO nanocomposite and an Ecoflex layer. The nanocomposite layer is fabricated using two different weight percentages (15 wt% and 20 wt%) and poled piezoelectric sheets, generating 2.63 V to 3.46 V. Variations regarding the nanogenerator's physical parameters were implemented to examine the effect on nanogenerator performance under different frequencies. The hybrid nanogenerator enabled energy harvesting for wearable devices. It was strapped on the side of the wrist to generate a potential difference with the motion of the wrist, creating a contact separation piezoelectric/triboelectric nanogenerator. Furthermore, a piezoelectric sheet was placed at the bottom of the wrist to harvest energy. The hybrid nanogenerator provided a maximum triboelectric response of 5.75 V and a maximum piezoelectric response of 2.85 V during wrist motion. The piezoelectric nanogenerator placed at the bottom of the wrist generated up to 4.78 V per wrist motion. [ABSTRACT FROM AUTHOR]

Background. Central post-stroke pain (CPSP) occurs following cerebrovascular accidents and is a neuropathic pain syndrome that is characterized by stimulation-independent pain; shooting, burning, or electric shock-like sensation and paresthesia. Multiple pathogenetic theories have been proposed for the CPSP including disinhibition, central sensitization, thalamic changes, and altered function of spinothalamic tract (STT). Investigations such as MRI DTI can help to understand the pathogenesis of CPSP. Objective. To determine the radiological and clinical biomarkers in cases with CPSP. Methods. This case-control study was retrospectively conducted upon 60 persons divided into 20 CPSP cases (group 1), 20 cases with no CPSP (group 2) and 20 healthy controls (group 3). All subjects had Routine MRI and complete neurological examination including “sensory testing” but stroke patients were evaluated by quantitative assessment of neuropathic pain, the National Institutes of Health Stroke Scale (NIHSS), Ashworth scale, Modified Rankin Scale (MRS) and Hamilton depression rating scale (HAM-D scale). Results. Significant differences existed among studied groups regarding motor examination, sensory examination, NIHSS score and Hamilton depression score. A non-significant difference was detected among the groups regarding MRS findings. A significant difference existed between groups 1 and 2, between groups 1 and 3 while no significant difference was detected between groups 2 and 3 for all FA readings and all ADC readings in ipsilateral affected side assessed at internal capsule, midbrain, and pons. No significant difference existed between groups 1 and 2, between groups 1 and 3 and between groups 2 and 3 regarding FA readings and ADC readings in contralateral side assessed at internal capsule, midbrain, and pons. Conclusion. Our study highlighted the significance of white matter tracts (WMT) other than the conventional pain path-ways in CPSP and can thus serve as a predictive marker for CPSP onset or a prognostic marker after any drug therapy or neuromodulatory treatment. [ABSTRACT FROM AUTHOR]

Background. Multiple sclerosis (MS) is a chronic inflammatory immune-mediated disease, distinguished by demyelination and oligodendropathy in the central nervous system. Cognitive impairment (CI) can impact patients at any stage of MS, including those with clinically isolated syndrome (CIS). Patients and methods. This is a prospective cross-sectional study which enrolled 60 patients with RRMS. They were subjected to cognitive scale assessment, routine brain MRI study and volumetric assessment of hippocampus. Results. This study found a significant positive correlation between duration of disease and Subjective memory complaints questionnaire (r=0.525, p=0.001). A significant negative correlation existed between disease duration and MMSE score (r=-0.404, p=0.001) and between disease duration and MoCA score (r=-0.310, p=0.016). No significant difference between both groups regarding the relative hippocampal volume. Mean relative right hippocampal volume is 0.0026 for cases versus 0.0027 among control group and mean relative left hippocampal volume is 0.0025 for cases versus 0.0026 among control group. Conclusion. Multiple sclerosis disease duration had an impact on cognitive state. However, hippocampal volume assessment did not predict the cognitive affection in patient with RRMS. [ABSTRACT FROM AUTHOR]

Background. Multiple sclerosis (MS) is an autoimmune disease that targets the central nervous system (CNS). A patient’s degree of demyelination and axonal degeneration can only be roughly estimated based on clinical symptoms, neuro-chemical analysis or standard clinical MRI. Magnetic resonance diffusion tensor imaging (DTI) may provide more information on MS pathology than T1- and T2-weighted MRI alone. Glial fibrillary acidic protein (GFAP) uniquely found in astrocytes in the (CNS), non-myelinating Schwann cells in the peripheral nervous system (PNS), and enteric glial cells. GFAP is postulated to be a biomarker of astrocytic damage and reactive astrogliosis. Methods. A total of 60 patients with MS was categorized into three equal groups according to The Multiple Sclerosis Progression Discussion Tool (MSProDiscuss tool): RRMS, SPMS, RRMS with high risk to become SPMS and 20 healthy controls. Baseline clinical characteristics and detailed medical and neurological history were taken into consideration, as well as time of onset of MS, delay in diagnosis, initial symptoms, relapses features and behavior, EDSS and disease modifying therapy. They were subjected to DTI-MRI and blood sampling for GFAP. Results. DTI was able to differentiate between different MS phenotypes and was able to detect progression when we evaluated DTI changes in NAWM in different brain areas as low FA and high MD were associated with progression and increasing disability (p value =0.001). Serum GFAP differs significantly between patients with SPMS or patients in transi)tion, also, it was higher in patients in transition than RRMS or control group (P value <0.001). There was a significant correlation between serum GFAP and DTI changes in NAWM as higher titres of GFAP were associated with lower FA and higher MD values in NAWM of frontal, temporal lobes, and CC body. Conclusion. Serum GFAP in addition to DTI measurable microdamage in NAWM can give us a wide scope of view about potential progression in MS pathology and related astrocytopathy. [ABSTRACT FROM AUTHOR]