Motor Nerve Conduction Research Articles

Homozygous Mutations in GDAP1 and MFN2 Genes Resulted in Autosomal Recessive Forms of Charcot-Marie-Tooth Disease in Consanguineous Pakistani Families.

Charcot-Marie-Tooth disease (CMT) is a heritable neurodegenerative disease of peripheral nervous system diseases in which more than 100 genes and their mutations are associated. Two consanguineous families Dera Ghazi Khan (PAK-CMT1-DG KHAN) and Layyah (PAK-CMT2-LAYYAH) with multiple CMT-affected subjects were enrolled from Punjab province in Pakistan. Basic epidemiological data were collected for the subjects. Nerve conduction study (NCS) and electromyography (EMG) were performed for the patients. Whole-exome sequencing (WES) followed by Sanger sequencing was applied to report the genetic basic of CMT. The NCS findings revealed that sensory and motor nerve conduction velocities for both families were <38 m/s. EMG presented denervation, neuropathic motor unit potential, and reduced interference pattern of peripheral nerves. WES identified that a novel nonsense mutation (c. 226 G>T) in GADP1 gene and a previously known missense mutation in MFN2 gene (c. 334 G>A) cause CMT4A (Charcot-Marie-Tooth disease type 4A) in the PAK-CMT1-DG KHAN family and CMT2A (Charcot-Marie-Tooth disease type 2A) in the PAK-CMT2-LAYYAH family, respectively. Mutations followed Mendelian pattern with autosomal recessive mode of inheritance. Multiple sequence alignment by Clustal Omega indicated that mutation-containing domain in both genes is highly conserved, and in situ analysis revealed that both mutations are likely to be pathogenic. We reported that a novel nonsense mutation and a previously known missense mutation in GAPD1 gene and MFN2 gene, respectively, cause CMT in consanguineous Pakistani families.

Sympathetic skin response for early detection of type 2 diabetic peripheral neuropathy and nephropathy.

Diabetic peripheral neuropathy (DPN) and diabetic nephropathy (DN) are common complications of type 2 diabetes mellitus (T2DM). Although nerve conduction studies (NCS) and sympathetic skin response (SSR) can detect DPN, the more sensitive method for early diagnosis remains unclear. Furthermore, whether DPN can be used as a predictor for diabetic nephropathy needs clarification. We evaluated nerve conduction studies, sympathetic skin response, and the diabetic nephropathy indicator microalbuminuria (MAU) in 192 patients with type 2 diabetes mellitus and 50 healthy controls. Patients with type 2 diabetes mellitus showed a lower sensory nerve conduction velocity (SCV), sensory active nerve potential (SNAP), motor nerve conduction velocity (MCV), and compound motor action potential (CMAP) than the controls on NCS. Abnormal rates for nerve conduction studies and sympathetic skin response were 75.0% and 83.3%, respectively, in patients with type 2 diabetes mellitus. Interestingly, 54.2% of patients with normal nerve conduction studies had an abnormal sympathetic skin response. Moreover, we found a positive correlation between sympathetic skin response and microalbuminuria for the first time. The abnormal rate of microalbuminuria was 53.8%, lower than that of abnormal nerve conduction studies or sympathetic skin response patients. Sympathetic skin response is a more sensitive method than nerve conduction studies for the early diagnosis of diabetic peripheral neuropathy. Abnormal sympathetic skin response might serve as an indicator for early diabetic nephropathy. Additionally, diabetic peripheral neuropathy may occur earlier than diabetic nephropathy in the development of type 2 diabetes mellitus.

Association of Sensory Nerve Action Potential Amplitude and Velocity With Type 2 Diabetic Peripheral Neuropathy.

There is ongoing controversy regarding the predominant type of nerve injury in diabetic peripheral neuropathy, whether it is demyelination or axonal degeneration. This study aimed to investigate the association between nerve conduction study parameters, specifically nerve conduction velocity and the amplitude of the action potential, with diabetic peripheral neuropathy and determine their potential as early indicators of the condition. A cross-sectional study was conducted involving diagnosed type 2 diabetes mellitus patients, who were divided into two groups: Group I (n = 111) with symptomatic diabetic peripheral neuropathy and Group II (n = 109) without clinically detectable peripheral neuropathy. Age and sex-matched healthy controls (n = 100) were also included. Nerve conduction velocity measurements were performed on both upper and lower limbs, with motor nerve conduction study focusing on the dominant side using the median and posterior tibial nervesand sensory nerve conduction study using the median and sural nerves. The nerve conduction studies revealed significantly lower sensory nerve action potential amplitudes and compound muscle action potential amplitudes in the median, posterior tibial, and sural nerves of the diabetic groups compared to the control subjects. Furthermore, these changes were more prominent in patients with peripheral neuropathy. Among the 220 diabetic patients analyzed, 135 (61.36%) exhibited nerve conduction abnormalities. The highest rate of abnormality was observed in the sural nerve, followed by the posterior tibial and median nerves. The most common abnormality detected in diabetic patients was a decrease in sensory nerve action potential, followed by a decrease in sensory nerve conduction velocity. The study findings suggest an association between reduced sensory nerve action potential amplitude and diabetic peripheral neuropathy. These results highlight the potential of sensory nerve action potential and velocity as a sensitive indicator of peripheral neuropathy in diabetic patients.

Efficacy and safety of Buyang Huanwu decoction for diabetic peripheral neuropathy: a systematic review and Metaanalysis.

To evaluate the efficacy and safety of Buyang Huanwu decoction (BYHWD) in treating diabetic peripheral neuropathy (DPN). Eight electronic databases, including China National Knowledge Infrastructure Database, Wanfang Database, China Science and Technology Journal Database, Chinese Biomedical Literature Database, Cochrane Library, Embase, Web of Science, and PubMed, were searched for randomized controlled trials (RCTs) of BYHWD to treat DPN. We identified all RCTs related to BYHWD and those on the treatment of DPN with the combination of mecobalamin. RevMan software was used for the statistical analysis. Twentyone RCTs with a total of 1945 patients were included. The methodological quality of the literature included was low. Metaanalysis showed that the efficacy of the treatment group was significantly better than that of the control group in the treatment of DPN with BYHWD [risk ratio () = 0.33, 95% (0.27, 0.40), 11.25, 0.000 01]. The median nerve of median motor nerve conduction velocity (MNCV) [mean difference () = 4.16, 95% (1.35, 6.98)] and median sensory NCV (SNCV) [(= 3.28, 95% (2.35, 4.22)] were improved in the treatment group. The MNCV in the common peroneal nerve [(= 1.63, 95% (0.39, 2.87)] and SNCV [(= 4.56, 95% (3.16, 5.97)] were significantly higher than those in the control group ( 0.01). Plasma viscosity [(= －0.15, 95% (－0.20, －0.09), 5.17, 0.01)], whole blood high shear [(= 0.83, 95% (1.56, －0.11), 2.26, 0.02)]and whole blood low shear [(= 1.61, 95% (2.28, 0.94), 4.68, 0.01)] decreased significantly after treatment. There was no significant difference in fasting blood glucose [(= 0.42, 95% ( 0.89, 0.05), 1.76, 0.08)] between the treatment and control groups; postprandial blood glucose [(= 0.62, 95% ( 1.19, 0.05), 2.12, 0.03)] decreased significantly. No significant difference was found in the blood lipid levels between the treatment and control groups, including triglycerides [(= 0.21, 95% (0.52, 0.10), 1.34, 0.18)] and cholesterol [(= 0.13, 95% ( 0.27, 0.00), 1.92, 0.06)]. Of the 21 RCTs, only five reported adverse reactions, and four studies reported the length of followup. No serious adverse events were reported. None of the studies reported the quality of life and economic conditions. Our study suggests that BYHWD has a significant therapeutic effect on DPN. Highquality, largescale RCTs are needed to provide more reliable evidence.

Nitrous-oxide-induced polyneuropathy and subacute combined degeneration of the spine: clinical and diagnostic characteristics in 70 patients, with focus on electrodiagnostic studies.

Nitrous oxide (N2 O) induced neurological symptoms are increasingly encountered. Our aim is to provide clinical and diagnostic characteristics with a focus on electrodiagnostic studies. Patients with neurological sequelae due to N2 O presenting in our hospital between November 2018 and December 2021 reporting clinical and diagnostic data were retrospectively reviewed. Seventy patients (median 22 years) were included. Median N2 O usage was 4 kg/week during 12 months. Patients' history revealed a higher rate of sensory symptoms compared to motor (97% vs. 57%) and 77% walking difficulties. Clinical diagnosis was polyneuropathy (PNP) in 44%, subacute combined degeneration (SCD) of the spine in 19%, both in 37%. Median vitamin B12 level was low (159 pmol/L), normal in 16%. The median methylmalonic acid was increased (2.66 μmol/L). Electrodiagnostic abnormalities were observed in 91%, with 72% fulfilling axonal PNP criteria, 20% showing mild to intermediate slowing. One patient fulfilled demyelinating PNP criteria not related to N2 O abuse (Charcot-Marie-Tooth type 1a). More prominent motor nerve conduction abnormalities were found; lower limbs were more affected. In 64% with normal conduction, myography showed signs of axonal loss. Magnetic resonance imaging showed cervical myelopathy in 58% involving generally five to six segments. Nitrous oxide (N2 O) leads to neurological symptoms by causing PNP and/or SCD primarily involving the legs. Distinguishing PNP and SCD clinically was shown to be insufficient. Electrodiagnostic studies showed axonal PNP. Demyelinating PNP due to N2 O abuse was not present in our cohort. Therefore, further diagnostic work-up is warranted if demyelinating features are present.

Facial nerve neurographies in intensive care unit-acquired weakness

BackgroundPatients with an intensive care unit-acquired weakness (ICU-AW) often present clinically with severe paresis of the limb and trunk muscles while facial muscles appear less affected. To investigate whether the facial nerves are partially spared from this condition, we performed both peripheral and cranial nerve conduction studies in critically ill patients.MethodsIn patients requiring prolonged ICU therapy, the motor and sensory nerve conduction velocities of the peroneal, ulnar and facial nerves and the muscle action potentials of the associated muscles, as well as the orbicularis oculi reflexes were assessed shortly after admission, and on ICU days 7 and 14.ResultsEighteen patients were included in the final data analysis (average age 54.2 ± 16.8 years, 8 females). The amplitudes of the peroneal nerve compound muscle action potentials (CMAPs) were reduced in all patients at ICU days 7 and 14 (F(1.39; 23.63) = 13.85; p < 0.001). There was no similar decrease in the CMAP amplitudes of the ulnar or facial nerve. Other parameters of nerve function (latencies, sensory and motor nerve conduction velocities, sensory nerve action potentials) remained unchanged. The reproducibility of the orbicularis oculi reflex was reduced during the disease course, while its latencies did not change significantly during the disease course.ConclusionsThere is a relative preservation of CMAPs in facial and hand as opposed to foot muscles. This is compatible with the clinical observation that the facial muscles in patients with ICU-AW are less severely affected. This may be primarily a function of the nerve length, and consequently more robust trophic factors in shorter nerves.Trial registration This study was prospectively registered in the German Clinical Trial Register on April 20th 2020 (DRKS00021467).

The Effects of Radial Extra Corporeal Shock Wave and Low-power Laser Therapies on Clinical and Electrophysiological Parameters in Moderate Carpal Tunnel Syndrome: A Blinded Randomized Control Trial

Objectives: Carpal tunnel syndrome (CTS) is a common peripheral entrapment neuropathy with squeezing of the median nerve and the patient is unable to function properly. There are different physiotherapy interventions for the management of these patients and recently, shock wave therapy and low-power laser (LPL) have been widely used, but there is no strong evidence comparing the effect of shock wave therapy and LLLT. Therefore, this trial was designed to compare the effect of extracorporeal shock wave therapy (ESWT), LPL, and routine interventions on clinical outcomes and electrophysiological parameters in patients with moderate CTS. Methods: Fifty-four patients were randomly assigned to the control (routine interventions), ESWT, and LPL therapy groups. All participants received transcutaneous electrical nerve stimulation (TENS) therapeutic ultrasound, hot pack, mobilization, and stretching for ten sessions over two weeks. Additionally, the ESWT group received radial ESWT in four sessions, and the LPL therapy group received laser in ten sessions. The primary outcomes were pain (assessed by the visual analog scale), function (assessed using the Boston questionnaire (BQ)), hand grip, and finger pinch strength. Secondary outcomes were electrophysiological parameters (distal motor and sensory latency and nerve conduction velocity (NCV) of the median nerve. Results: Time group interactions were significant for pain, the symptom severity subscale of BQ, finger pinch, and hand grip strength (p&lt;0.001). Significant improvements were seen in clinical and sensory latency and motor NCV of the median nerve (p&lt;0.05). The ESWT group experienced significant improvements with a large effect size in pain, function, and finger pinch strength compared to the control group (p&lt;0.01). Additionally, the LPL therapy group showed significant changes in the function and finger pinch and hand grip strength compared to the control group. There were no significant differences between the LPL therapy and ESWT groups except for pain in favor of the ESWT group. No significant differences were found among the three groups in electrophysiological parameters (p&gt;0.05). Discussion: Although laser therapy increased the efficacy of routine interventions, it seems adding ESWT to the routine treatment may be superior for the management of moderate CTS patients.

Nerve excitability test and lead toxicity: a case-control study

BackgroundAlthough conventional electrophysiological parameters have been proposed as clinical indicators for monitoring lead neuropathies, their correlations with blood lead level are weak. In this study, we investigated the applicability of nerve excitability tests (NETs) to evaluate lead intoxication.MethodsFourteen workers who were exposed to lead with an elevated blood level ranging from 17.8 to 64.9 µg/dL and 20 healthy controls with similar ages and body heights were enrolled. Both workers and controls underwent nerve conduction studies (NCSs), motor evoked potentials (MEPs) with transcranial magnetic stimulation (TMS), and NETs.ResultsNCSs showed prolonged distal latencies and decreased motor nerve conduction velocity of median nerves in the workers but without significant correlation to blood lead level (BLL). Significantly prolonged MEP latency was observed in the workers (+ 6 ms). NETs demonstrated hyperpolarized resting membrane potentials in stimulus-response curves and changes in the property of potassium channels under a hyperpolarized current in threshold electrotonus, implying that lead hyperpolarized nerves by interfering with potassium channels. NETs also showed a better correlation with BLL than conventional electrophysiological parameters.ConclusionsAxonal hyperpolarization and central conduction delay are more apparently reflecting elevated BLL than NCS. NET may have the potential for early detection of lead neuropathy.

AAV9-mediated SH3TC2 gene replacement therapy targeted to Schwann cells for the treatment of CMT4C

Type 4C Charcot-Marie-Tooth (CMT4C) demyelinating neuropathy is caused by autosomal recessive SH3TC2 gene mutations. SH3TC2 is highly expressed in myelinating Schwann cells. CMT4C is a childhood-onset progressive disease without effective treatment. Here, we generated a gene therapy for CMT4C mediated by an adeno-associated viral 9 vector (AAV9) to deliver the human SH3TC2 gene in the Sh3tc2-/- mouse model of CMT4C. We used a minimal fragment of the myelin protein zero (Mpz) promoter (miniMpz), which was cloned and validated to achieve Schwann cell-targeted expression of SH3TC2. Following the demonstration of AAV9-miniMpz.SH3TC2mycvector efficacy to re-establish SH3TC2 expression in the peripheral nervous system, we performed an early as well as a delayed treatment trial in Sh3tc2-/- mice. We demonstrate both after early as well as following late treatment improvements in multiple motor performance tests and nerve conduction velocities. Moreover, treatment led to normalization of the organization of the nodes of Ranvier,which is typically deficient in CMT4C patients and Sh3tc2-/- mice, along with reduced ratios of demyelinated fibers, increased myelin thickness and reduced g-ratios at both time points of intervention. Taken together, our results provide a proof of concept for an effective and potentially translatable gene replacement therapy for CMT4C treatment.

Peripheral Polyneuropathy in Children and Young Adults with Ataxia-Telangiectasia.

Ataxia-telangiectasia (A-T) is a rare, autosomal recessive, multisystem disorder that leads to progressive neurodegeneration with cerebellar ataxia and peripheral polyneuropathy. Cerebellar neurodegeneration is well described in A-T. However, peripheral nervous system involvement is an underdiagnosed but important additional target for supportive & systemic therapies. The aim was to conduct neurophysiological measurements to assess peripheral neurodegeneration and the development of age-dependent neuropathy in A-T. In this prospective study 42 classical A-T patients were assessed. The motor and sensory nerve conduction of the median and tibial nerves was evaluated. Data was compared to published standard values and a healthy age-gender-matched control group of 23 participants. Ataxia scores (Klockgether, SARA) were also assessed. In A-T neurophysiological assessment revealed neuropathic changes as early as the first year of life. Subjective symptomatology of neuropathy is rarely described. In the upper extremities, motor neuropathy was predominantly that of a demyelinating type and sensory neuropathy was predominantly that of a mixed type. In the lower extremities, motor and sensory neuropathy were predominantly that of a mixed type. We found significant correlations between age and the development of motor and sensory polyneuropathy in A-T compared with healthy controls (p<0.001). In A-T, polyneuropathy occurs mostly subclinical as early as the first year of life. The current study of a large national A-T cohort demonstrates that development of neuropathy in A-T differs in the upper and lower extremities.

Afterdischarges in myotonic dystrophy type 1.

Electrodiagnostic testing is an important screening test for myotonic dystrophy type 1 (DM1). Although myotonic discharges are observed on electromyography in cases of DM1, it is difficult to distinguish DM1 from other myotonic disorders clinically. In the present study, afterdischarges, another type of pathological potential revealed by electrodiagnostic testing, were analyzed, and their role in distinguishing DM1 from other myotonic disorders was explored. Data from 33 patients with myotonic discharges on electromyography were analyzed retrospectively. According to gene testing, the patients were divided into DM1 (n = 20) and non-DM1 myotonia (n = 13) groups. Afterdischarges were investigated by retrospectively evaluating the electrodiagnostic findings of motor nerve conduction studies, F-waves, and repetitive nerve stimulations. Afterdischarges were observed in 17 of the 20 patients with DM1, with an occurrence rate of approximately 85%. However, afterdischarges were absent in all patients with non-DM1 myotonia. There were significant differences in the occurrence rate between the two groups (P < 0.01). Afterdischarges may serve as a suggestive role in clinical diagnosis of DM1. The discovery that DM1 can present with afterdischarges may pave a new way to study the pathogenesis of DM1.

Recurrent laryngeal motor nerve conduction studies in a rat model: Establishing an objective measure for investigating laryngeal innervation.

Disease or injury can cause neuromuscular changes to the larynx that can affect voice, breathing, and swallowing. Motor nerve conduction studies have had limited use in the study of laryngeal neurophysiology, despite their importance in other anatomic sites. The aim of this study was to explore the feasibility of performing recurrent laryngeal motor nerve conduction studies (rlMNCS) in a rat model. rlMNCS were performed in 15 rats under anesthesia. A bipolar stimulating electrode was placed on the recurrent laryngeal nerve (RLN) 5 mm below the cricoid cartilage. Via direct laryngoscopy, a recording electrode was placed transorally into the thyroarytenoid muscle. The RLN was maximally stimulated to determine the compound muscle action potential (CMAP). Three consecutive trials were averaged. The mean stimulating threshold to the RLN to achieve a CMAP from the thyroarytenoid was 1.7 ± 0.6 mA. RLN stimulation caused a visible adductor twitch of the vocal fold in all animals. The mean negative amplitude was 2.0 ± 0.8 mV, and the total area was 1.0 ± 0.4 mV ms. The CMAP latency and negative duration were 1.0 ± 0.1 ms and 0.9 ± 0.2 ms, respectively. rlMNCS are feasible and may be useful in understanding laryngeal neurophysiology with disease or injury. This work could provide a tractable animal model for studying and monitoring treatment of neuromuscular conditions affecting voice, breathing, and swallowing.

Gene replacement therapy in two Golgi-retained CMT1X mutants before and after the onset of demyelinating neuropathy

X-linked Charcot-Marie-Tooth disease type 1 (CMT1X) is a demyelinating neuropathy resulting from loss-of-function mutations affecting the GJB1/connexin 32 (Cx32) gene. We previously showed functional and morphological improvement in Gjb1-null mice following AAV9-mediated delivery of human Cx32 driven by the myelin protein zero (Mpz) promoter in Schwann cells. However, CMT1X mutants may interfere with virally delivered wild-type (WT) Cx32. To confirm the efficacy of this vector also in the presence of CMT1X mutants, we delivered AAV9-Mpz-GJB1 by lumbar intrathecal injection in R75W/Gjb1-null and N175D/Gjb1-null transgenic lines expressing Golgi-retained mutations, before and after the onset of the neuropathy. Widespread expression of virally delivered Cx32 was demonstrated in both genotypes. Re-establishment of WT Cx32 function resulted in improved muscle strength and increased sciatic nerve motor conduction velocities in all treated groups from both mutant lines when treated before as well as after the onset of the neuropathy. Furthermore, morphological analysis showed improvement of myelination and reduction of inflammation in lumbar motor roots and peripheral nerves. In conclusion, this study provides proof of principle for a clinically translatable gene therapy approach to treat CMT1X before and after the onset of the neuropathy, even in the presence of endogenously expressed Golgi-retained Cx32 mutants.

Motor outcomes in patients with infantile and juvenile Pompe disease: Lessons from neurophysiological findings.

In Infantile Onset Pompe Disease (IOPD), enzyme replacement therapy (ERT) may improve survival, cardiac function, and motor development. However, even with early enzyme replacement therapy, some patients experienced poor response to ERT and abnormal motor milestones that could be due to motor neuron involvement. In this long-term retrospective study, we analyzed concomitant clinical motor outcomes and electroneuromyography (ENMG) findings in patients with IOPD and Juvenile Onset Pompe Disease (JOPD). Twenty-nine pediatric patients were included and 20 surviving were analyzed for neuromotor studies: 12 had IOPD (group 1), 4 had JOPD (group 2) and 4 (group 3) received ERT in the first month of age. Motor nerve conduction studies were mostly normal. Needle EMG performed at diagnosis always indicated the existence of myopathy that responded to ERT. Two IOPD patients (group 1) presenting with mixed motor neuropathy and myopathy displayed a poor outcome and never walked. Two patients became non-walkers (one IOPD patient and one patient of group 3) at respectively 9 and 3years of age. One JOPD patient is about to lose walking ability. This motor deterioration was associated with the development of a motor neuropathy. Patients older than 10years of age develop a motor neuropathy. Initial or secondary motor neuron involvement seems to be associated with a poor motor outcome showing that ERT may fail to prevent the accumulation of glycogen in motor neuron. Neurophysiological findings are important to assess severity of motor neuron damage in all Pompe pediatric patients and should be systematically performed.

Dietary interventions improve diabetic kidney disease, but not peripheral neuropathy, in a db/db mouse model of type 2 diabetes.

Patients with type 2 diabetes often develop the microvascular complications of diabetic kidney disease (DKD) and diabetic peripheral neuropathy (DPN), which decrease quality of life and increase mortality. Unfortunately, treatment options for DKD and DPN are limited. Lifestyle interventions, such as changes to diet, have been proposed as non-pharmacological treatment options for preventing or improving DKD and DPN. However, there are no reported studies simultaneously evaluating the therapeutic efficacy of varying dietary interventions in a type 2 diabetes mouse model of both DKD and DPN. Therefore, we compared the efficacy of a 12-week regimen of three dietary interventions, low carbohydrate, caloric restriction, and alternate day fasting, for preventing complications in a db/db type 2 diabetes mouse model by performing metabolic, DKD, and DPN phenotyping. All three dietary interventions promoted weight loss, ameliorated glycemic status, and improved DKD, but did not impact percent fat mass and DPN. Multiple regression analysis identified a negative correlation between fat mass and motor nerve conduction velocity. Collectively, our data indicate that these three dietary interventions improved weight and glycemic status and alleviated DKD but not DPN. Moreover, diets that decrease fat mass may be a promising non-pharmacological approach to improve DPN in type 2 diabetes given the negative correlation between fat mass and motor nerve conduction velocity.

An injectable, self-healing, electroconductive hydrogel loaded with neural stem cells and donepezil for enhancing local therapy effect of spinal cord injury

BackgroundSpinal cord injury (SCI) is a serious injury with high mortality and disability rates, and there is no effective treatment at present. It has been reported that some treatments, such as drug intervention and stem cell transplantation have positive effects in promoting neurological recovery. Although those treatments are effective for nerve regeneration, many drawbacks, such as low stem cell survival rates and side effects caused by systemic medication, have limited their development. In recent years, injectable hydrogel materials have been widely used in tissue engineering due to their good biocompatibility, biodegradability, controllable properties, and low invasiveness. The treatment strategy of injectable hydrogels combined with stem cells or drugs has made some progress in SCI repair, showing the potential to overcome the drawbacks of traditional drugs and stem cell therapy.MethodsIn this study, a novel injectable electroactive hydrogel (NGP) based on sodium hyaluronate oxide (SAO) and polyaniline-grafted gelatine (NH2-Gel-PANI) was developed as a material in which to load neural stem cells (NSCs) and donepezil (DPL) to facilitate nerve regeneration after SCI. To evaluate the potential of the prepared NGP hydrogel in SCI repair applications, the surface morphology, self-repairing properties, electrical conductivity and cytocompatibility of the resulting hydrogel were analysed. Meanwhile, we evaluated the neural repair ability of NGP hydrogels loaded with DPL and NSCs using a rat model of spinal cord injury.ResultsThe NGP hydrogel has a suitable pore size, good biocompatibility, excellent conductivity, and injectable and self-repairing properties, and its degradation rate matches the repair cycle of spinal cord injury. In addition, DPL could be released continuously and slowly from the NGP hydrogel; thus, the NGP hydrogel could serve as an excellent carrier for drugs and cells. The results of in vitro cell experiments showed that the NGP hydrogel had good cytocompatibility and could significantly promote the neuronal differentiation and axon growth of NSCs, and loading the hydrogel with DPL could significantly enhance this effect. More importantly, the NGP hydrogel loaded with DPL showed a significant inhibitory effect on astrocytic differentiation of NSCs in vitro. Animal experiments showed that the combination of NGP hydrogel, DPL, and NSCs had the best therapeutic effect on the recovery of motor function and nerve conduction function in rats. NGP hydrogel loaded with NSCs and DPL not only significantly increased the myelin sheath area, number of new neurons and axon area but also minimized the area of the cystic cavity and glial scar and promoted neural circuit reconstruction.ConclusionsThe DPL- and NSC-laden electroactive hydrogel developed in this study is an ideal biomaterial for the treatment of traumatic spinal cord injury.

Electrodiagnostic profile of conduction slowing in amyotrophic lateral sclerosis

ObjectiveSince motor nerve conduction slowing can occur due to loss of large axons, we investigate the conduction slowing profile in amyotrophic lateral sclerosis (ALS) and identify the limits beyond which the diagnosis of exclusive axonal loss is unlikely. MethodsFirst, using linear regression analysis, we established the range of motor conduction slowing in 76 chronic inflammatory demyelinating polyneuropathy (CIDP) patients. Demyelinating range confidence intervals were defined by assessing conduction velocity (CV), distal latency (DML), and F-wave latency (F) in relation to distal compound muscle action potential (CMAP) amplitude of median, ulnar, fibular, and tibial nerves. Results were subsequently validated in 38 additional CIDP patients. Then, the newly established demyelination confidence intervals were used to investigate the profile of conduction slowing in 95 ALS patients. ResultsCV slowing, prolonged DML, and abnormal F were observed in 22.2%, 19.6%, and 47.1% of the studied nerves respectively in ALS patients. When slowing occurred, it affected more than one segment of the motor nerve, suggesting that CMAP amplitude dependent conduction slowing caused by an exclusive loss of large axons is the main mechanism of slowing. No ALS patient had more than 2 nerves with CV slowing in the confidence interval defined by the regression equations or the American Academy of Neurology (AAN) research criteria for CIDP diagnosis. ConclusionsThe presence of more than two motor nerves with CV slowing in the demyelinating range defined by the regression analysis or AAN criteria in ALS patients suggests the contribution of acquired demyelination or other additional mechanisms exist in the electrodiagnostic profile of ALS.

Survey of body mass index (BMI) on median motor nerve conduction velocity (NCV) in normal population of Malwa region

: Nerve conduction studies reveal technique to work on peripheral nerve being capable in revealing nerve-related issue. It aids in distinguishing from a nerve injury to situation where muscles are affected due to a nerve lesion. While, in that respect much dissimilarity persist in use of Nerve Conduction Velocity (NCV) in different nerves with regard to place, sex, mass &amp; other ethnographical facts i.e. Span of life. This has been viewed in performing nerve conduction studies while ethnograpical part differs for different geological region.: The purpose of present work is to do the Nerve Conduction Variables (NCV) studies in rt. median nerve in usual well young of Malwa region and to study the outcome of B.M.I on it. : A total 110 healthy participants from the periods of 20 and 50 years, with none nerve lesion, being examined at IMCHRC, Indore. All trial were completed on JAVA RMSAleron-201 series. Scrutiny on SPSS 10.0 series. : The mean of NCV firstly rises among periods of 20-30 yrs, 31-40 yrs &amp; 40-50years, preceded by a fall in the mean NCV of elbow–wrist segment which significantly fall while the mean of B.M.I rises with increasing length of life. It is to be noted that NCV was inversely related to an increase in B.M.I in the volunteer the mean NCV of Set 1 &amp;#62; Set2, Set3, Set 4 with P &amp;#60; 0.05 that toply relevant.Usual parameter for conduction in peripheral nerves to be used in the test of peripheral nerve lesion. B.M.I has a definitive effect on NCV. So, this factor has been put into concern during interpretation of results during nerve conduction studies. Therefore, it should also be used for research purposes &amp; in prognosis approach.

Clinical and neurophysiological recovery of ulnar nerve conduction block at the elbow.

An important mechanism of peripheral nerve motor and sensory dysfunction is conduction block (CB). However, recovery from mechanically induced CB has been rarely studied in humans. The aim of this study was to describe clinical, electrodiagnostic (EDx), and ultrasonographic (US) characteristics of CB recovery in ulnar neuropathy at the elbow (UNE). We recruited a group of consecutive patients presenting to our EDx laboratory with UNE and >50% motor CB. Patients' histories were obtained and neurologic, EDx, and US examinations were repeated every 1-3 mo for at least 12 mo. We studied 10 patients (5 men), with a mean age of 63 y (range, 51-81 y). In all affected arms CB was localized to the retrocondylar groove. Following conservative management, myometrically measured index finger abduction improved from a median of 49% to 100% relative to the contralateral index finger, and ulnar nerve CB decreased from a median of 74% to 6%. Most of the improvement took place within 8 mo of symptom onset, and 6 mo after receiving treatment instructions. Mean motor nerve conduction velocity improved from 15 to 27 m/s in the most affected 2-cm ulnar nerve segment. The resolution of CB after typical chronic compression may take longer than after acute compression. This should be considered by clinicians when estimating prognosis for discussions with patients.

Effects of Low-Dose Citicoline on the Electrical Conduction Function of the Crushed Sciatic Nerve of Rats

Introduction: Citicoline has therapeutic and beneficial effects in a variety of neurologic disorders and neurodegenerative diseases. The aim of this study was to examine the beneficial effects of low doses of citicoline for the early period of administration in rat sciatic nerve crush injury by using electrophysiological and biochemical approaches. Methods: Thirty-two adult male Wistar rats were divided into four groups (n = 8 in each) and treated as follows: sham-operated (intact, saline), control (crushed sciatic nerve, saline), 50C (crushed sciatic nerve, 50 mg/kg citicoline), and 250C (crushed sciatic nerve, 250 mg/kg citicoline). At the end of the 7-day experimental period, motor nerve conduction velocities (MNCVs) were determined using in vivo electrodes and fresh rat blood was collected for biochemical analysis. Results: MNCVs were significantly reduced in crushed sciatic nerve of rats but significantly increased after 7 days of citicoline administration. Improved electrophysiological recovery in the citicoline groups was significant when compared to the control group. In addition, citicoline exacerbated the decrease in total glutathione level and glutathione reductase and catalase activities but decreased malondialdehyde levels compared to the control group. Conclusion: Results presented in this paper suggest that low doses of citicoline for the early period of administration have a promotional effect on improving the electrical conduction function of the sciatic nerve.