Motor Nerve Function Research Articles

Multimodal Neural Response and Effect Assessment During a BCI-Based Neurofeedback Training After Stroke.

Stroke caused by cerebral infarction or hemorrhage can lead to motor dysfunction. The recovery of motor function is vital for patients with stroke in daily activities. Traditional rehabilitation of stroke generally depends on physical practice under passive affected limbs movement. Motor imagery-based brain computer interface (MI-BCI) combined with functional electrical stimulation (FES) is a potential active neural rehabilitation technology for patients with stroke recently, which complements traditional passive rehabilitation methods. As the predecessor of BCI technology, neurofeedback training (NFT) is a psychological process that feeds back neural activities online to users for self-regulation. In this work, BCI-based NFT were proposed to promote the active repair and reconstruction of the whole nerve conduction pathway and motor function. We designed and implemented a multimodal, training type motor NFT system (BCI-NFT-FES) by integrating the visual, auditory, and tactile multisensory pathway feedback mode and using the joint detection of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). The results indicated that after 4 weeks of training, the clinical scale score, event-related desynchronization (ERD) of EEG patterns, and cerebral oxygen response of patients with stroke were enhanced obviously. This study preliminarily verified the clinical effectiveness of the long-term NFT system and the prospect of motor function rehabilitation.

Sistem Pakar Diagnosis Penyakit Saraf Motorik Menerapkan Metode Fuzzy Mamdani

Motor nerve diseases are a group of neurological disorders that cause gradual loss of muscle strength. Motor nerves are divided into two types, namely upper motor neurons and lower motor neurons. The UMN originates in the brain and is responsible for sending signals from the brain to the brainstem or to the spinal cord. While the LMN originates from the brain stem and spinal cord, and functions to transmit signals to all muscles. The signals sent are used to regulate body muscle movements, such as walking, gripping, breathing, speaking, or swallowing. When motor nerve function is disturbed, the sufferer will find it difficult to carry out these movements. Problems that occur in the RSU. Mitra Medika Medan in the process of consulting patients who experience motor nerve disease problems, namely the process of diagnosing motor nerve diseases using the services of an expert doctor in the field of motor nerve disease diagnosis by consulting conventional methods, the time needed to serve many patients is less efficient, so long queues can be avoided. so that not a few patients feel disappointed. Overcome problems that occur in RSU. Mitra Medika Medan, it is necessary to have a tool in the form of an expert system that provides diagnostic results in accordance with expert knowledge. Therefore, in this study, the authors built an expert system for diagnosing motor neuron disease using visual-based visual basic net 2008 by applying the Mamdani method as a method of solving diagnostic problems in the expert system that was built

Peripheral Blood Mononuclear Cells Regulate Differentially Expressed Proteins in the Proximal Sciatic Nerve of Rats after Transection Anastomosis

Peripheral nerve injury (PNI) is a common disease that causes the partial loss of sensory, exercise, and autonomic nervous function. In clinical practice, accurate end-to-end neurorrhaphy of the epineurium without tension is the ideal treatment when there is no nerve defect. We have confirmed that peripheral blood mononuclear cells (PBMCs) can effectively improve nerve regeneration and motor function recovery after PNI. However, the global protein profile and signaling conduction pathways regulated by PBMCs remain unclear. This study employed the transection anastomosis model to detect the walking track analysis, gastrocnemius wet weight rate, and morphological examination in order to validate the effect of PBMCs on sciatic nerve injury in rats. Results showed that PBMCs improved nerve regeneration after sciatic nerve dissociation and anastomosis in rats, which reflected in the improvement of the sciatic nerve function index, wet weight rate of gastrocnemius muscles, muscle fiber structure, and the number of axons. We then used TMT labeling quantitative proteomics to explore the underlying mechanism by which PBMCs ameliorated sciatic nerve injury. Results showed that PBMCs regulated 40 differential proteins and the regulated proteins were primarily involved in the complement and coagulation cascade pathways, the notch signaling pathway, the renin angiotensin system, DNA replication, histidine metabolism, β-alanine metabolism, and other types of O-glycan biosynthesis. Immunohistochemical results supported our findings on the changes in expression of Kininogen 1 and Psen1, the relationships between PNI and the notch pathway and the complement and coagulation level pathways.

A Comparative Study of Sensory and Motor Peripheral Nerve Functions in Elderly Patients of Diabetes Mellitus and Non-Diabetic Controls in a Tertiary Care Hospital

Introduction: In elderly diabetics, peripheral neuropathy is a significant cause of morbidity and physical disability. Diabetes Mellitus, and its chronic complications like peripheral neuropathy have been instrumental in contributing to the physical decline in the elderly. However, objective assessment of physical ability in elderly diabetics and devising their correlation to reduced peripheral nerve functions has been a hitherto uncharted territory. This study aims at evaluating the peripheral nerve functions in elderly diabetics. This study hypothesizes that peripheral nerve functions were significantly reduced in elderly diabetics in comparison to elderly nondiabetics. Materials and Method: Relevant history, prescriptions and laboratory reports were collected from the study participants. Sensory functions were tested by 10g Semmes-Weinstein Monofilament Test and Vibration Perception Threshold (VPT) was tested by handheld biothesiometer. Motor functions were tested by the Compound Muscle Action Potential and Nerve Conduction Velocity (CMAP and NCV respectively) for the peroneal nerve (preferably of right side). Fisher exact test has been applied barring the parameters for nerve function with respect to Monofilament and VPT. For Monofilament and VPT, Z statistic has been used to test the differences in proportion. Results: Most of the diabetic patients were overweight. NCV and CMAP were significantly reduced in diabetics. Mean NCV in diabetic group was 37.81 m/s as compared to 42.08 in non-diabetic. Mean CMAP in diabetics was 2.55 mV as compared to 3.21 mV in non-diabetic. Our study showed that number of participants with impaired VPT and monofilament test was higher in diabetics than non-diabetics. Conclusion: Diabetic patients are more prone to develop peripheral neuropathy. Assessment of the clinical homologue of these pathological processes is the first step in implementing the appropriate type of intervention. Treatment should be individualized to take into account specific manifestations and the underlying pathogenesis of each patient's unique clinical presentation. Keywords: Diabetes Mellitus, Nerve Function, Peripheral Neuropathy.

Associations of Lower Extremity Peripheral Nerve Impairment and Risk of Dementia in Black and White Older Adults.

Peripheral nerve impairments and dementia are common among older adults and share risk factors. However, few studies have examined whether peripheral nerve function and dementia are associated. We evaluated whether lower extremity peripheral nerve impairments were associated with higher incidence of dementia and whether associations differed by comorbidity subgroups (diabetes, low vitamin B12, and APOE ε4 allele carriers). We studied Black and White Health, Aging, and Body Composition Study participants 70 to 79 years of age and without dementia at enrollment. Lower extremity sensory and motor peripheral nerve function was measured at year 4 (the analytic baseline of this study). Sensory nerve impairments were measured with monofilament (1.4 g, 10 g) and vibration threshold of the toe. Monofilament insensitivity was defined as unable to detect monofilament (3 of 4 touches), and vibration detection impairment was defined as >130 μm. Fibular motor impairments were defined as <1 mV compound motor action potential (CMAP) amplitude and slow nerve conduction velocity <40 m/s. Incident dementia over the following 11 years was determined from medical records, cognitive scores, and medications. Cox proportional hazard models adjusted for demographics and health conditions assessed associations of nerve impairments with incident dementia. Among 2,174 participants (52% women, 35% Black), 45% could not detect monofilament 1.4 g, 9% could not detect monofilament 10 g, 6% could not feel vibration, 10% had low CMAP amplitude, and 24% had slow conduction velocity. Monofilament 10 g (hazard ratio [HR] 1.35, 95% CI 0.99-1.84) and vibration detection insensitivity (HR 1.73, 95% CI 1.24-2.40) were associated/borderline associated with a higher risk of dementia after covariate adjustment. Estimates were elevated but not significant for monofilament 1.4 g, CMAP amplitude, and conduction velocity (p > 0.05). Increasing number of peripheral nerve impairments was associated with higher risk of dementia in a graded fashion; for ≥3 impairments, the HR was 2.37 (95% CI 1.29-4.38). In subgroup analyses, effect estimates were generally higher among those with diabetes, low vitamin B12, and APOE ε4 allele except for vibration detection. Peripheral nerve impairments, especially sensory, were associated with a higher risk of dementia even after adjustment for age and other health factors. These associations may represent a shared susceptibility to nervous system degeneration.

Electroactive Scaffolds to Improve Neural Stem Cell Therapy for Spinal Cord Injury.

Spinal cord injury (SCI) is a serious condition caused by damage to the spinal cord through trauma or disease, often with permanent debilitating effects. Globally, the prevalence of SCI is estimated between 40 to 80 cases per million people per year. Patients with SCI can experience devastating health and socioeconomic consequences from paralysis, which is a loss of motor, sensory and autonomic nerve function below the level of the injury that often accompanies SCI. SCI carries a high mortality and increased risk of premature death due to secondary complications. The health, social and economic consequences of SCI are significant, and therefore elucidation of the complex molecular processes that occur in SCI and development of novel effective treatments is critical. Despite advances in medicine for the SCI patient such as surgery and anaesthesiology, imaging, rehabilitation and drug discovery, there have been no definitive findings toward complete functional neurologic recovery. However, the advent of neural stem cell therapy and the engineering of functionalized biomaterials to facilitate cell transplantation and promote regeneration of damaged spinal cord tissue presents a potential avenue to advance SCI research. This review will explore this emerging field and identify new lines of research.

Application of Data Mining in the Effect of Traditional Chinese Medicine on the Rehabilitation of Cerebral Spasticity of Lower Extremity Exercise Energy.

In this article, we have examined the effect of acupoint injection of mecobalamin on the nerve function of the lower limbs of stroke patients by giving acupoint injection of mecobalamin for 2 weeks in patients with stroke, effectively fusing acupuncture, acupoints, and drugs in traditional Chinese medicine to rehabilitate the effect of motor function and activities of daily living. For this purpose, a total of 60 study cases will be screened in the study. They are randomly divided into experimental group and control group: the control group will be treated with conventional stroke treatment and nursing, and the experimental group will be treated with bilateral acupoint injection of mecobalamin; once a day, after 14 days of continuous injection, we observed and intervened the lower limb nerve function, motor function, and activities of daily living of the two groups before and after the treatment and statistically analyzed the data so as to obtain the clinical effect of the treatment on the lower limb rehabilitation of stroke patients. Before the intervention, the general information and basic clinical data of the two groups of subjects were collected for baseline comparison, and the differences between the two groups of subjects' lower limb nerve function, motor function and activities of daily living before the intervention were compared. Comparison of lower limb neurological deficits mainly include comparison between groups and comparison within groups. Comparison of lower limb motor function mainly include comparison between groups and comparison within groups. (1) Acupoint injection of mecobalamin therapy and simple stroke rehabilitation therapy have good results. (2) Acupoint injection of mecobalamin can improve the neurological deficits of the lower limbs of stroke patients more than simple conventional stroke therapy, and it also has a rehabilitation effect in nourishing the nerves, improving circulation, and protecting the brain. (3) Point-injection mecobalamin therapy is more effective than conventional stroke therapy in improving the motor function of the lower limbs and promoting the rehabilitation of the lower limbs of patients with ischemic stroke. (4) Acupoint injection of mecobalamin therapy can improve the activities of daily living of patients with ischemic stroke and improve the quality of life of patients compared with conventional stroke therapy alone.

Evaluation of Laryngeal Motor Neuropathy Using Transcranial Magnetic Stimulation-Mediated Evoked Potentials.

Contemporary evaluation of vocal fold motion impairment largely relies on clinical laryngoscopy, with the diagnoses of vocal fold paresis (VFPa) and paralysis (VFP) being based on identification of partial and complete restriction of gross vocal fold motion, respectively. No consensus exists on the diagnostic criteria of VFPa. Laryngeal electromyography does not offer any insight into nerve conduction velocity without the adjunction of nerve conduction studies, which are impractical to perform on laryngeal nerves due to their anatomic location. The present study aims to assess the feasibility of laryngeal nerve conduction studies using transcranial magnetic stimulation (TMS)-mediated myogenic evoked potentials in the evaluation of laryngeal motor nerve function. Prospective controlled cohort study. Enrollment of three groups of subjects defined as healthy volunteers, subjects with clinically diagnosed unilateral VFP, and subjects with clinically diagnosed unilateral VFPa of peripheral etiology. Electrodiagnostic studies consisting of bilateral stimulation of the laryngeal motor cortex, proximal cisternal, and peripheral portions of the vagus nerves were performed using figure-of-eight magnetic stimulation coils, and myogenic evoked potentials recorded from bilateral thyroarytenoid, cricothyroid, and posterior cricoarytenoid muscles using indwelling hook wire electrodes. Conduction latencies were plotted against demographic and anthropometric variables. Values obtained in healthy volunteers were used as normative references and compared to aggregated latencies of VFP and VFPa groups. Enrolled subjects included 19 healthy volunteers, 5 subjects with VFP, and 4 subjects with VFPa. Normative laryngeal nerve conduction latency ranges measured in healthy subjects were comparable to prior published values, and recorded latencies increased in positive correlation with age. VFPa subjects exhibited increased latencies in affected nerve sites, while VFP subjects presented more variability in electrophysiologic manifestations, mostly dependent on their degree of compensatory reinnervation. Aberrant and synkinetic reinnervation patterns were more predominant in the VFP group than the VFPa group. Laryngeal nerve conduction studies using TMS-mediated myogenic evoked potentials are safely feasible. They may serve as a useful complement to laryngeal electromyography in the evaluation of motor laryngeal neuropathy and represent a promising diagnostic modality in the evaluation of VFPa. Based on the present study's findings, the commonly accepted notion of VFPa as a manifestation of a less severe form of neuropathy than VFP may be unsubstantiated. Aging may contribute to progressive motor nerve dysfunction. Future investigations are needed to ascertain the role of nerve conduction studies in clinical laryngology practice. 3 Laryngoscope, 132:S1-S12, 2022.

Partial Restoration of Spinal Cord Neural Continuity via Sural Nerve Transplantation Using a Technique of Spinal Cord Fusion.

BackgroundSpinal cord injury (SCI) can cause paralysis and serious chronic morbidity, and there is no effective treatment. Based on our previous experimental results of spinal cord fusion (SCF) in mice, rats, beagles, and monkeys, we developed a surgical protocol of SCF for paraplegic human patients. We designed a novel surgical procedure of SCF, called sural nerve transplantation (SNT), for human patients with lower thoracic SCI and distal cord dysfunction.MethodsWe conducted a clinical trial (ChiCTR2000030788) and performed SNT in 12 fully paraplegic patients due to SCI between T1 and T12. We assessed pre- and postoperative central nerve pain, motor function, sensory function, and autonomic nerve function. Conduction of action potentials across the sural nerve transplant was evaluated. Neural continuity was also examined by diffusion tensor imaging (DTI).ResultsAmong the 12 paraplegic patients enrolled in this clinical trial, seven patients demonstrated improved autonomic nerve functions. Seven patients had clinically significant relief of their symptoms of cord central pain. One patient, however, developed postoperative cord central pain (VAS: 4). Five patients had varying degrees of recovered sensory and/or motor functions below the single neurologic level 1 month after surgery. One patient showed recovery of electrophysiologic, motor-evoked potentials 6 months after the operation. At 6 months after surgery, DTI indicated fusion and nerve connections of white cord and sural nerves in seven patients.ConclusionSNT was able to fuse the axonal stumps of white cord and sural nerve and at least partially improve the cord central pain in most patients. Although SNT did not restore the spinal cord continuity in white matter in some patients, SNT could restore spinal cord continuity in the cortico-trunco-reticulo-propriospinal pathway, thereby restoring in part some motor and sensory functions. SNT may therefore be a safe, feasible, and effective method to treat paraplegic patients with SCI. Future clinical trials should be performed to optimize the type/technique of nerve transplantation, reduce surgical damage, and minimize postoperative scar formation and adhesion, to avoid postoperative cord central pain.Clinical Trial Registration[http://www.chictr.org.cn/showproj.aspx?proj=50526], identifier [ChiCTR2000030788].

Interleukin 37's role in promoting nerve repair and attenuating immune rejection of peripheral nerve xenografts in mice

BackgroundThe aim of the study was to explore the potential role of IL-37 in nerve repair and immune regulation in peripheral nerve xenograft hosts.MethodsRat nerve xenografts were transplanted into mouse recipients. Transplanted mice received an intraperitoneal injection of IL-37 on the day before transplantation, whereas control mice remained untreated. At postoperative 2, 4, 8, and 12 weeks, the effects of IL-37 were examined on motor function, tissue morphology, and regenerative ability of xenograft nerves. Levels of IL-17 and IL-22 in serum and spleen were measured at 3, 7, 14, and 28 days after nerve transplantation.ResultsAt 12 postoperative weeks, grafted nerves grew well in IL-37 treatment group, as documented by the recovery in function of sciatic nerves compared to untreated controls. In particular, IL-37-treated mice showed more complete neuromorphology, thicker myelin sheath, compact structure, and the increased number of myelinated nerve fibers in histological examination. The number of T helper (Th)17 (CD3 + CD4 + IL-17+) and Th22 (CD3 + CD4 + IL-22+) cells in the spleen was reduced in the IL-37-treated group, as well as serum IL-17 and IL-22 were decreased after IL-37 treatment compared with the untreated group.ConclusionsIL-37 attenuates immunomodulatory responses induced by xenografts, contributing to the recovery of nerve function and the prevention of muscle atrophy caused by nerve grafts.

Effects of progressive resistance training in individuals with type 2 diabetic polyneuropathy: a randomised assessor-blinded controlled trial.

The aim of this study was to evaluate the effects of progressive resistance training (PRT) on muscle strength, intraepidermal nerve fibre density (IENFD) and motor function in individuals with type 2 diabetic polyneuropathy (DPN) and to compare potential adaptations to those of individuals with type 2 diabetes without DPN and healthy controls. This was an assessor-blinded trial conducted at the Neurology department, Aarhus University Hospital. Adults with type 2 diabetes, with and without DPN and healthy control participants were randomised to either supervised PRT or non-PRT for 12 weeks. Allocation was concealed by a central office unrelated to the study. The co-primary outcomes were muscle strength in terms of the peak torque of the knee and ankle extensors and flexors, and IENFD. Secondary outcome measures included the 6 min walk test (6MWT), five-time sit-to-stand test (FTSST) and postural stability index obtained by static posturography. A total of 109 individuals were enrolled in three groups (type 2 diabetes with DPN [n = 42], type 2 diabetes without DPN [n = 32] and healthy control [n = 35]). PRT resulted in muscle strength gains of the knee extensors and flexors in all three groups using comparative analysis (DPN group, PRT 10.3 ± 9.6 Nm vs non-PRT -0.4 ± 8.2 Nm; non-DPN group, PRT 7.5 ± 5.8 Nm vs non-PRT 0.6 ± 8.8 Nm; healthy control group, PRT 6.3 ± 9.0 Nm vs non-PRT -0.4 ± 8.4 Nm; p<0.05, respectively). Following PRT the DPN group improved the 6MWT (PRT 34.6 ± 40.9 m vs non-PRT 2.7 ± 19.6 m; p=0.001) and the FTSST (PRT -1.5 ± 2.2 s vs non-PRT 1.5 ± 4.6 s; p=0.02). There was no change in IENFD following PRT in any of the groups. PRT improved muscle strength of the knee extensors and flexors and motor function in individuals with type 2 diabetic polyneuropathy at levels comparable with those seen in individuals with diabetes without DPN and healthy control individuals, while no effects were observed in IENFD. ClinicalTrials.gov NCT03252132 FUNDING: Research reported in this paper is part of the International Diabetic Neuropathy Consortium (IDNC) research programme, supported by a Novo Nordisk Foundation Challenge Program grant (grant no. NNF14OC0011633) and Aarhus University.

Deranged Blood Sugar Levels in Type 2 Diabetics induced impairment of nerve conduction

Background: One of the complications of diabetes is Peripheral neuropathy that becomes the source of frailty and indisposition. Metabolic malfunction is the root cause in diabetes that target nerve damage. Aim: To evaluate electrophysiological case research with respect to effect of diabetics on nerves and to link it along with blood sugar Methods: Assessment of nerves related to of upper limb was carried out for motor nerve by aid of computerized system and surface electrodes in 40 male individuals suffering from type 2 and 40 healthy males. The ulnar and median nerve was selected for case research. Parameters that were being discussed included conduction velocity and distal latency Results: Diabetics have increased distal delay and reduced conduction velocity. These variables were linked to blood sugar levels in diabetics. Conclusions: There is affect to nerves in case of diabetes as shown by poor motor nerve function and depicted via testing electro physiologically. Increase in sugar blood levels is associate with damage to nerves. Keywords: Electrophysiological tests, Conduction velocity, Peripheral neuropathy, Diabetes,

Motor imagery with visual feedback inhibits excitability of the spinal motor nerve function and improves motor skills

Motor imagery with visual feedback inhibits excitability of the spinal motor nerve function and improves motor skills

Acellular nerve grafts supplemented with induced pluripotent stem cell-derived exosomes promote peripheral nerve reconstruction and motor function recovery

Peripheral nerve injury is a great challenge in clinical work due to the restricted repair gap and weak regrowth ability. Herein, we selected induced pluripotent stem cells (iPSCs) derived exosomes to supplement acellular nerve grafts (ANGs) with the aim of restoring long-distance peripheral nerve defects. Human fibroblasts were reprogrammed into iPSCs through non-integrating transduction of Oct3/4, Sox2, Klf4, and c-Myc. The obtained iPSCs had highly active alkaline phosphatase expression and expressed Oct4, SSEA4, Nanog, Sox2, which also differentiated into all three germ layers in vivo and differentiated into mature peripheral neurons and Schwann cells (SCs) in vitro. After isolation and biological characteristics of iPSCs-derived exosomes, we found that numerous PKH26-labeled exosomes were internalized inside SCs through endocytotic pathway and exhibited a proliferative effect on SCs that were involved in the process of axonal regeneration and remyelination. After that, we prepared ANGs via optimized chemical extracted process to bridge 15 mm long-distance peripheral nerve gaps in rats. Owing to the promotion of iPSCs-derived exosomes, satisfactory regenerative outcomes were achieved including gait behavior analysis, electrophysiological assessment, and morphological analysis of regenerated nerves. Especially, motor function was restored with comparable to those achieved with nerve autografts and there were no significant differences in the fiber diameter and area of reinnervated muscle fibers. Taken together, our combined use of iPSCs-derived exosomes with ANGs demonstrates good promise to restore long-distance peripheral nerve defects, and thus represents a cell-free strategy for future clinical applications.

Normal Values of the Second Interosseous Pinch: A Measurement of Pure Ulnar-Innervated Intrinsic Muscles of the Hand

The second palmar interosseous muscle is innervated solely by the ulnar nerve, and second palmar interosseous pinch (2IP) strength may be a good indicator of ulnar nerve motor function. The goal of this study was to describe the 2IP test and establish its normative values, stratified by age, sex, and dominance. Volunteers were recruited to participate in this study at various community locations. Patients over the age of 18 years were eligible for this study. Demographic information on all subjects was collected. The volunteers were asked to pinch a hydraulic pinch gauge between the index and middle finger proximal phalanges with the proximal and distal interphalangeal joints flexed and without recruiting the thumb. Three 2IP measurements were taken for each hand. Descriptive statistics and analysis of covariance were performed to determine the effect of age, sex, dominance, and side on 2IP. We analyzed the 2IP strength using the 2IP test across 3 trials to determine whether it was affected by repeated testing. Two hundred thirty-eight patients met the inclusion criteria (45 ± 21 years, 55% women, 87% right-hand dominant). There was no statistically significant difference between dominant and nondominant hands or among the 3 trials. There was a statistically significant correlation between age and 2IP strength ranging between 0.32 and 0.44 kg. Age and sex showed a statistically significant association with 2IP strength, with patients of older age and women having weaker 2IP. We determined normative values for 2IP strength using a sample from a normal population. More studies are needed to validate these results. Second interosseous pinch strength may be a useful tool to assess ulnar nerve function.

Circulating testosterone and dehydroepiandrosterone are associated with individual motor unit features in untrained and highly active older men

Long-term exercise training has been considered as an effective strategy to counteract age-related hormonal declines and minimise muscle atrophy. However, human data relating circulating hormone levels with motor nerve function are scant. The aims of the study were to explore associations between circulating sex hormone levels and motor unit (MU) characteristics in older men, including masters athletes competing in endurance and power events. Forty-three older men (mean ± SD age: 69.9 ± 4.6 years) were studied based on competitive status. The serum concentrations of dehydroepiandrosterone (DHEA), total testosterone (T) and estradiol were quantified using liquid chromatography mass spectrometry. Intramuscular electromyographic signals were recorded from vastus lateralis (VL) during 25% of maximum voluntary isometric contractions and processed to extract MU firing rate (FR), and motor unit potential (MUP) features. After adjusting for athletic status, MU FR was positively associated with DHEA levels (p = 0.019). Higher testosterone and estradiol were associated with lower MUP complexity; these relationships remained significant after adjusting for athletic status (p = 0.006 and p = 0.019, respectively). Circulating DHEA was positively associated with MU firing rate in these older men. Higher testosterone levels were associated with reduced MUP complexity, indicating reduced electrophysiological temporal dispersion, which is related to decreased differences in conduction times along axonal branches and/or MU fibres. Although evident in males only, this work highlights the potential of hormone administration as a therapeutic interventional strategy specifically targeting human motor units in older age.

Are multidisciplinary neurodevelopmental profiles of children born very preterm at age 2 relevant to their long-term development? A preliminary study

ABSTRACT To identify distinctive multidisciplinary neurodevelopmental profiles of relatively healthy children born very preterm (VPT) and describe the longitudinal course of these profiles up to age 10. At 2 years of corrected age, 84 children born VPT underwent standardized testing for cognitive, language, speech, motor, behavioral, and auditory nerve function. These data were submitted to factor and cluster analysis. Sixty-one of these children underwent cognitive, language, and behavioral assessment again at age 10. Descriptive statistics were used to analyze longitudinal trajectories for each profile. Four neurodevelopmental profiles were identified at age 2. Profile 1 children (n = 22/26%) had excellent cognitive-language-motor function, normal behavioral and auditory nerve function, but showed an unexpected severe decline up to age 10. Profile 2 children (n = 16/19%) had very low behavioral function, low cognitive-language-motor function, and accelerated auditory nerve function. Their scores remained low up until age 10. Profile 3 children (n = 17/20%) had delayed auditory nerve function, low behavioral function, and slightly lower cognitive-language-motor function. They showed the most increasing trajectory. Profile 4 children (n = 29/35%) had very low cognitive-language-motor function, normal behavioral and auditory nerve function, but showed wide variation in their trajectory. Our preliminary study showed that a multidisciplinary profile-oriented approach may be important in children born VPT to improve counseling and provide targeted treatment for at risk children. High performers at age 2 may not be expected to maintain their favorable development. Behavioral problems might negatively impact language development. Delayed auditory nerve function might represent a slow start and catch-up development.

Autonomic and Somatic Nerve Functions in Type 2 Diabetes Mellitus Patients: Electrophysiological Aspects.

Objectives: To investigate the relationship between neurophysiological sensory and motor nerve function parameters, assessed by nerve conduction studies (NCS) with parasympathetic autonomic function and by heart rate variability (HRV) tests in patients with type 2 diabetes mellitus (T2DM). Material and Methods: A total of 161 T2DM patients underwent NCS. Cardiac autonomic response was assessed by HRV tests to deep breathing (HRV DB), to Valsalva manoeuvre, and during postural change from lying to standing. Results: The amplitude of motor response in the median nerve, tibial nerve, and peroneal nerve was associated with reduced HRV DB (p = 0.0001). The amplitude of motor response in the median nerve, tibial nerve, and peroneal nerve was associated with reduced HRV Valsalva (p = 0.0001). The correlation between the amplitude of response in all sensory nerves (sural, median, and ulnar) and HRV DB was statistically significant (p = 0.0001). Conclusion: The results indicate that there is a correlation in T2DM patients between the damage of small myelinated and unmyelinated nerve fibres from cardiac autonomic nerves, assessed by HRV tests and damage of large motor and sensory fibres, assessed by NCS. Based on the above results, a combination of NCS and HRV tests should be considered in the neurophysiological approach to diabetic neuropathy.

Krüppel-like factor 7 attenuates hippocampal neuronal injury after traumatic brain injury.

Our previous study has shown that the transcription factor Krüppel-like factor 7 (KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury. KLF7 also participates in traumatic brain injury, but its regulatory mechanisms remain poorly understood. In the present study, an HT22 cell model of traumatic brain injury was established by stretch injury and oxygen-glucose deprivation. These cells were then transfected with an adeno-associated virus carrying KLF7 (AAV-KLF7). The results revealed that, after stretch injury and oxygen-glucose deprivation, KLF7 greatly reduced apoptosis, activated caspase-3 and lactate dehydrogenase, downregulated the expression of the apoptotic markers B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) and cleaved caspase-3, and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2. Furthermore, KLF7 overexpression upregulated Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygen-glucose deprivation. Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3. In addition, treatment with AG490, a selective inhibitor of JAK2/STAT3, weakened the protective effects of KLF7. A mouse controlled cortical impact model of traumatic brain injury was then established. At 30 minutes before modeling, AAV-KLF7 was injected into the ipsilateral lateral ventricle. The protein and mRNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury. KLF7 reduced ipsilateral hippocampal atrophy, decreased the injured cortex volume, downregulated Bax and cleaved caspase-3 expression, and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression. Moreover, KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus. These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injury through activation of the JAK2/STAT3 signaling pathway. The study was approved by the Institutional Review Board of Mudanjiang Medical University, China (approval No. mdjyxy-2018-0012) on March 6, 2018.

Eccentric exercise causes delayed sensory nerve conduction velocity but no repeated bout effect in the flexor pollicis brevis muscles.

This study was aimed at investigating the effect of eccentric contractions (ECCs) of flexor pollicis brevis muscles (FPBMs) on motor and sensory nerve functions as well as the ipsilateral repeated bout effect (IL-RBE) and contralateral (CL)-RBE of motor and sensory nerve conduction velocities following ECCs. Thirty-two young healthy men (age: 19.6 ± 0.2years, height: 173.2 ± 1.2cm, body mass: 69.7 ± 1.9kg) performed two bouts of ECCs. During the first ECCs bout (ECCs-1), all participants performed 100 ECCs with 1 hand; for the second bout, 3 groups (2weeks [W]: n = 11, 4W: n = 10, 8W: n = 11) performed ECCs with both hands 2, 4, or 8weeks after ECCs-1. The maximal voluntary isometric contraction (MVC), range of motion (ROM), visual analog scale for pain (VAS), motor and sensory nerve conduction velocities were measured before, immediately after, and 1, 2, 3, and 5days after ECCs. ECCs-1 decreased the MVC, limited the ROM, developed VAS, and decreased the motor and sensory nerve conduction velocities compared tonon-exercise hand (p < 0.05). The repeated bout effect was observed in the ROM for IL-RBE in 2W and 4W, VAS for IL-RBE in 2W, and ROM and VAS for CL-RBE in 2W (p < 0.05). However, RBEs of MVC and motor and sensory nerve conduction velocities were not observed, and no differences were confirmed depending on the interval. In the present study, ECCs of the FPBM caused a sensory nerve dysfunction, while IL- or CL-RBE was not observed.