Spinal Cord Conduction Research Articles

Human-induced pluripotent stem cell-derived neural stem/progenitor cell ex vivo gene therapy with synaptic organizer CPTX for spinal cord injury

The transplantation of neural stem/progenitor cells (NS/PCs) derived from human induced pluripotent stem cells (hiPSCs) has shown promise in spinal cord injury (SCI) model animals. Establishing a functional synaptic connection between the transplanted and host neurons is crucial for motor function recovery. To boost therapeutic outcomes, we developed an exvivo gene therapy aimed at promoting synapse formation by expressing the synthetic excitatory synapse organizer CPTX in hiPSC-NS/PCs. Using an immunocompromised transgenic rat model of SCI, we evaluated the effects of transplanting CPTX-expressing hiPSC-NS/PCs using histological and functional analyses. Our findings revealed a significant increase in excitatory synapse formation at the transplantation site. Retrograde monosynaptic tracing indicated extensive integration of transplanted neurons into the surrounding neuronal tracts facilitated by CPTX. Consequently, locomotion and spinal cord conduction significantly improved. Thus, exvivo gene therapy targeting synapse formation holds promise for future clinical applications and offers potential benefits to individuals with SCI.

Postural balance impairment of the trunk in adolescents with mesial ratio of dentition before and after surgical treatment in the presence and absence of congenital cervical spine abnormalities

BACKGROUND: In the presence of mandibular malformations and malocclusion, an abnormal morphology of the cervical spine is often detected. Latent neurological abnormalities in patients with possible disorders of spinal cord conduction function are promising in assessing the degree of postural balance impairment, which is well diagnosed by stabilometry.
 AIM: To evaluate the dynamics of postural stability in adolescents with the mesial ratio of dentition, with and without congenital cervical spine abnormalities, before and after reconstructive operations on the jaws with a constructive bite.
 MATERIALS AND METHODS: Clinical, radiographic, and two-platform stabilometric studies were conducted in 31 patients aged 15–17 years with combined dentomaxillofacial anomalies, having a mesial ratio of dentition. The main group included 10 adolescents with various congenital cervical spine abnormalities detected by multispiral computed tomography (CT). The control group included 21 patients who did not have CT signs of cervical spine abnormalities. The stabilometric parameters of the movement of the general body pressure center and the pressure centers of the contralateral lower extremities were evaluated in these patients before surgical correction of the bite and from 1 month to 1 year after it.
 RESULTS: In the main group, postural balance impairment was noted, which was more pronounced before surgical treatment than those in the control group. This was manifested by frontal–sagittal violations of postural stability, pathological increase in the areas of statokinesiograms, linear velocities of the centers of pressure, and abnormally severe asymmetry of stabilometric parameters between the contralateral lower extremities. After the surgical correction of the bite, signs of postural balance deterioration were recorded in the control group: a significant increase in the coefficient, i.e., a sharp change in the direction of movement of the general center of pressure from 18% [15%–20%] to 23% [15%–31%], and the asymmetry of the linear velocities of the centers of pressure of the contralateral lower extremities significantly increased from 0.9 [0.3–1.6] to 2.2 [0.9–4.4] mm/s. In the main group, a positive trend was observed—a change in these parameters toward normalization: that is, a tendency to decrease the coefficient and a significant decrease in the rate of the centers of pressure.
 CONCLUSIONS: To improve the quality of comprehensive diagnostics and medical rehabilitation of adolescents with congenital and combined dentomaxillofacial anomalies, additional radiographic examination of the cervical spine in combination with stabilometric and kinematic assessment of posture is necessary.

Electrophysiological evidence of diabetes' impacts on central conduction recoveries in degenerative cervical myelopathy after surgery.

To assess the impact of diabetes mellitus (DM) on the postoperative motor and somatosensory functional recoveries of degenerative cervical myelopathy (DCM) patients. Motor and somatosensory evoked potentials (MEP and SSEPs) and modified Japanese Orthopedic Association (mJOA) scores were recorded in 27 diabetic (DCM-DM group) and 38 non-diabetic DCM patients (DCM group) before and 1 year after surgery. The central motor (CMCT) and somatosensory (CSCT) conduction time were recorded to evaluate the conductive functions of the spinal cord. The mJOA scores, CMCT and CSCT improved (t test, p < 0.05) in both of the DCM-DM and DCM groups 1year after surgery. The mJOA recovery rate (RR) and CSCT recovery ratio were significantly worse (t test, p < 0.05) in the DCM-DM group compared to the DCM group. DM proved to be a significant independent risk factor for poor CSCT recovery (OR = 4.52, 95% CI 2.32-7.12) after adjusting for possible confounding factors. In DCM-DM group, CSCT recovery ratio was also correlated with preoperative HbA1 level (R = - 0.55, p = 0.003). Furthermore, DM duration longer than 10years and insulin dependence were risk factors for lower mJOA, CMCT and CSCT recoveries among all DCM-DM patients (t test, p < 0.05). DM may directly hinders spinal cord conduction recovery in DCM patients after surgery. Corticospinal tract impairments are similar between DCM and DCM-DM patients, but significantly worsened in chronic or insulin-dependent DM patients. The dorsal column is more sensitively affected in all DCM-DM patients. Deeper investigation into the mechanisms and neural regeneration strategies is needed.

Somatosensory evoked potentials of the tibial nerve during the surgical decompression of thoracolumbar intervertebral disk herniation in dogs.

This study aimed to identify the impact on spinal cord integrity and determine the electrophysiological safety level during surgery for thoracolumbar intervertebral disk herniation in dogs. A total of 52 dogs diagnosed with thoracolumbar intervertebral disk herniation were enrolled. The tibial nerve somatosensory evoked potential elicited on the scalp by stimulation of the tibial nerve was recorded before and during hemilaminectomy. Both the amplitude and latency of the somatosensory evoked potential were periodically registered, and the percentage changes from the pre-operative control values (amplitude rate and latency rate) were calculated. When the multifidus muscles were retracted after removal from the spinous processes and vertebrae, the somatosensory evoked potential amplitude rate decreased in all dogs, while the latency rate increased in 33 dogs examined. The amplitude rate remained unchanged during the halting procedure, loosening retraction, and hemilaminectomy. After removing the disc material from the spinal canal, the amplitude rate was increased. The somatosensory evoked potential latency increased when the multifidus muscles were retracted and shortened after multifidus muscles closure in four cases. The outcome of all cases showed improvement in clinical signs 7 days after operation. Spinal cord conduction is impaired by retraction of the multifidus muscles and improved by removal of disk materials. Maintaining intraoperative SEP amplitudes above 50% of control may help avoid additional spinal cord injury during surgery. Since we have no case that worsened after the surgery, however, further studies are necessary to confirm this proposal.

Pengaruh Mobilisasi Dini terhadap Berkemih Spontan Pasca Bedah Sesar dengan Anestesi Spinal di Rumah Sakit TK. IV IM 07.01 Lhokseumawe

Cesarean section requires anesthetic efforts to relieve pain in the patient. The type of anesthesia commonly used is spinal anesthesia. Urinary retention is one of the side effect on using spinal anesthetic drugs caused by blockade of spinal cord conduction as high as the S2-S4 segment which innervates the urinary bladder which can lead to UTI. One of the actions that can accelerate spontaneous voiding is early mobilization step by step after cesarean section. This study aims to determine the effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe. Method that used in this research is quasi-experimental design with one-group posttest-only design, a population of 53 mothers after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe in October - November 2021. Data analysis used univariate and bivariate with Fisher Exact Test with 95% confidence level, = 5%. The result showed there was an effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe with p value = 0.037 and OR = 6.346 (95% CI = 1.091-36.921). The conclusion of the study that there is an effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe in 2021 and early mobilization had an effect 6 times on the initial time of voiding.

Pengaruh Mobilisasi Dini terhadap Berkemih Spontan Pasca Bedah Sesar dengan Anestesi Spinal di Rumah Sakit TK. IV IM 07.01 Lhokseumawe

Cesarean section requires anesthetic efforts to relieve pain in the patient. The type of anesthesia commonly used is spinal anesthesia. Urinary retention is one of the side effect on using spinal anesthetic drugs caused by blockade of spinal cord conduction as high as the S2-S4 segment which innervates the urinary bladder which can lead to UTI. One of the actions that can accelerate spontaneous voiding is early mobilization step by step after cesarean section. This study aims to determine the effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe. Method that used in this research is quasi-experimental design with one-group posttest-only design, a population of 53 mothers after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe in October - November 2021. Data analysis used univariate and bivariate with Fisher Exact Test with 95% confidence level, = 5%. The result showed there was an effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe with p value = 0.037 and OR = 6.346 (95% CI = 1.091-36.921). The conclusion of the study that there is an effect of early mobilization on spontaneous voiding after cesarean section with spinal anesthesia at Level IV IM 07.01 Hospital Lhokseumawe in 2021 and early mobilization had an effect 6 times on the initial time of voiding.

Human menstrual blood-derived stem cells combined with a new 3D bioprinted composite scaffold for spinal cord injury treatment

Spinal cord injury (SCI) regeneration and repair is a worldwide medical issue, and stem cell therapy is an emerging treatment strategy. Previously, our research group found that transplanting menstrual blood-derived mesenchymal stem cells (MenSCs) can promote axon regeneration in rats SCI. However, the SCI pathological microenvironment inhibits stem cell survival after transplantation. The acellular spinal cord is the most similar to the spinal cord in terms of three-dimensional structure and natural biological activity, and it can efficiently regulate axon growth and promote synapse formation. Based on recent progress in the understanding of scar-free spinal cord repair in neonatal mice, it was postulated that in the acellular spinal cord microenvironment of neonatal rats, it would be more active ingredients to promote axon regeneration and inhibit glial scars, than in the adult rat. The hypothesis was formulated that a new 3D bioprinted scaffold with neonatal acellular spinal cord/GelMA hydrogel/MenSCs would efficiently repair SCI. The neonatal acellular spinal cord can provide a dual bionic microenvironment for axon regeneration, optimizing bioactive composition and microstructure, and the GelMA hydrogel guarantees the scaffold's mechanical properties. Then, using 3D bioprinting technology, the pore size of the scaffold can be precisely controlled, and the spinal cord conduction tract path may be stimulated. Moreover, a tissue-engineered spinal cord can be constructed by planting MenSCs in the pores. Overall, our hypothesis suggests that 3D bioprinted neonatal acellular spinal cord/GelMA hydrogel composite scaffold coupled with MenSCs might have more beneficial therapeutic effects on spinal cord injury rehabilitation.

Effects of the combination therapy of electric field stimulation and polyethylene glycol in the ex vivo spinal cord of female rats after compression.

The application of electric field stimulation (EFS) can reduce the cation influx after spinal cord injury. However, regenerated cation influx and reestablished injury potential are observed after EFS. Polyethylene glycol (PEG) is popular as an effective cell membrane fusion agent. This study aims to determine the effects of the combination therapy of EFS and PEG in the ex vivo spinal cord after compression. The ex vivo spinal cords of female rats with compression injury were incubated in a double sucrose gap recording chamber (DSGRC) and randomly divided into the following four groups: (1) compression group: compression only, (2) EFS group: EFS for 15min, (3) PEG group: PEG treatment for 4min, and (4) EFS+PEG group: EFS for 15min and PEG treatment for 4min. The hematoxylin-eosin staining was performed to measure the necrotic area of the spinal cords. The gap potential was detected, and the area under the curve of the gap potential was calculated. The intracellular cation concentration, membrane permeability, and compound action potential were measured and quantified. Results revealed no significant difference in the necrotic areas among different groups, and the compression model of the ex vivo spinal cord in the DSGRC had high consistency and stability. The combination therapy could attenuate cation inflow, promote cell membrane restoration, and promote the functional recovery of the spinal cord conduction after compression in ex vivo spinal cords.

Electrophysiological evaluation in 4 patients with diabetic pseudotabes

BACKGROUNDResearches on diabetic nervous system lesion are mainly focus on peripheral nerve and vegetative nerve, so there are few investigations on diabetic pseudotabes. OBJECTIVETo investigate the electrophysiological examinations on the diagnosis of diabetic pseudotabes. DESIGNCase study. SETTINGDepartment of Electrophysiology and Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University. PARTICIPANTSA total of 4 patients with type 2 diabetes mellitus, including 3 males and 1 female aged from 50 to 72 years, were selected from Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University from March 2002 to February 2005. All accepted subjects met the modified diagnostic criteria of diabetes mellitus, which was set by American Diabetes Mellitus Association (ADA) in 1997. Otherwise, the subjects had typical symptoms and physical signs of spinal posterior funiculus damage. However, patients with spinal cord lesion which was caused by other factors were excluded. All accepted subjects provided the confirmed consent. METHODSNicolet NT electromyography (EMG)/evoked potential meter (made in the USA) was used to detect spinal cord conduction velocity (SCCV), somatosensory evoked potential (SEP) of lower limbs, motor nerve conduction velocity (MNCV) and sensory nerve conduction velocity (SNCV) of extremities. Determining criteria: Measurements were performed based on the laboratory standards. SCCV, which was less than lower limit of normal value (T2–12: 40 – 55 m/s, T12 – L4: 20 – 41 m/s, T2 – L4: 36 – 45 m/s), was regarded as abnormal. SEP value of lower limbs: P40, P60 and PF, which were more than standard deviation of normal value (x+2.5), were regarded as the abnormality. Normal value of P40, P60 and PF latencies (x±s) in this study: P40, P60 and PF in males were (37.6±1.9) ms, (59.8±3.9) ms and (7.6±0.9) ms, respectively; meanwhile, those in females were (35.5±1.7) ms, (55.2±2.7) ms and (6.3±0.7) ms, respectively. MNCV and SNCV, which were less than 50 m/s in upper limbs and 40 m/s in lower limbs, were regarded as the abnormality. MAIN OUTCOME MEASURESElectrophysiological examinations. RESULTSAll 4 patients with type 2 diabetes mellitus were involved in the final analysis. (1) SCCV: Among 4 patients, SCCV of three patients was decreased in T2 – 12, T12 – L4 and T2 – L4, and that of the other one was decreased in T2–12 and T2 – L4; however, SCCV in T12 – L4 was normal. There was significant difference as compared with normal value (P < 0.01). (2) SEP of lower limbs: SEP values of lower limbs were abnormal in all 4 patients. Among them, P40, P60 and PF latencies of two patients were delayed; P40 of one patient was delayed and PF was not drained out; P40 and P60 of the last one were delayed and PF was normal. (3) MNCV and SNCV: The MNCV and SNCV were normal in one patient and abnormal in three patients. The results demonstrated that MNCV and SNCV of extremities decreased; especially, sensory nerve action potential (SNAP) of both lower extremities of one patient were not drained out. CONCLUSIONDetections of SCCV, SEP of lower limbs, MNCV and SNCV of extremities are helpful to investigate whether peripheral nerve and deep sensory passage are damaged or not and determine whether deep sensory damage is caused by peripheral nerve and spinal posterior funiculus.

Cerebrolysin enhances spinal cord conduction and reduces blood-spinal cord barrier breakdown, edema formation, immediate early gene expression and cord pathology after injury.

Spinal cord evoked potentials (SCEP) are good indicators of spinal cord function in health and disease. Disturbances in SCEP amplitudes and latencies during spinal cord monitoring predict spinal cord pathology following trauma. Treatment with neuroprotective agents preserves SCEP and reduces cord pathology after injury. The possibility that cerebrolysin, a balanced composition of neurotrophic factors improves spinal cord conduction, attenuates blood-spinal cord barrier (BSCB) disruption, edema formation, and cord pathology was examined in spinal cord injury (SCI). SCEP is recorded from epidural space over rat spinal cord T9 and T12 segments after peripheral nerves stimulation. SCEP consists of a small positive peak (MPP), followed by a prominent negative peak (MNP) that is stable before SCI. A longitudinal incision (2mm deep and 5mm long) into the right dorsal horn (T10 and T11 segments) resulted in an immediate long-lasting depression of the rostral MNP with an increase in the latencies. Pretreatment with either cerebrolysin (CBL 5mL/kg, i.v. 30min before) alone or TiO2 nanowired delivery of cerebrolysin (NWCBL 2.5mL/kg, i.v.) prevented the loss of MNP amplitude and even enhanced further from the pre-injury level after SCI without affecting latencies. At 5h, SCI induced edema, BSCB breakdown, and cell injuries were significantly reduced by CBL and NWCBL pretreatment. Interestingly this effect on SCEP and cord pathology was still prominent when the NWCBL was delivered 2min after SCI. Moreover, expressions of c-fos and c-jun genes that are prominent at 5h in untreated SCI are also considerably reduced by CBL and NWCBL treatment. These results are the first to show that CBL and NWCBL enhanced SCEP activity and thwarted the development of cord pathology after SCI. Furthermore, NWCBL in low doses has superior neuroprotective effects on SCEP and cord pathology, not reported earlier. The functional significance and future clinical potential of CBL and NWCBL in SCI are discussed.

Intraoperative response of the pyramidal system to surgical correction of spinal deformities of various etiologies

Objective . To assess the information value of comparing the results of formalizing intraoperative changes in transcranial motor evoked potentials during surgical correction of spinal deformities of various etiologies. Material and Methods . Study design: analysis of monocentric retrospective unselected cohort over 5 years, evidence class 2b. Surgical correction of spinal deformity under neurophysiological control was performed in 364 patients (mean age 12.80 ± 0.40 years). The scores of changes in motor evoked potentials were used to compare the pyramidal system response to surgical aggression in patients with congenital spinal deformities, idiopathic scoliosis, and systemic skeletal diseases. Results. Basic motor responses in patients with systemic diseases of the axial skeleton are to a greater extent depressed and unstable than in those with congenital deformity and idiopathic scoliosis. On surgery completion, these differences are exacerbated. Five identified types of response of the spinal cord conduction pathways to surgical correction of spinal deformity allow comparing intraoperative neuromonitoring results in different groups of patients. The most dangerous types of response are observed more often in patients with congenital and systemic pathologies than in those with idiopathic scoliosis. Conclusion . The proposed method for the rank assessment of intraoperative changes in motor evoked potentials during surgical correction of spinal deformity allows comparative studies of patients’ reactions to surgical intervention in different etiological and age groups. The greatest risk of iatrogenic motor disorders in the postoperative period is observed in patients with systemic skeletal pathology.

Potentiation of spinal cord conduction and neuroprotection following nanodelivery of DL-3-n-butylphthalide in titanium implanted nanomaterial in a focal spinal cord injury induced functional outcome, blood-spinal cord barrier breakdown and edema formation.

Spinal cord injury (SCI) is a devastating disease inflicting lifetime disability to the victims. Military personnel are quite often victims of SCI for which no suitable therapeutic strategies have been developed so far. The main reason for SCI induced disability is loss of neural connections below and above the lesion site causing motor paralysis and somatosensory disturbances Loss of neuronal connections thwart spinal cord conduction resulting in motor function disability. To enhance spinal cord conduction grafting of peripheral nerves, implant of hydrogels filled with neuroprotective drugs is used but so far, no satisfactory results re achieved. In this regards implants of microelectrode for enhancing tissue connectivity is suggested that is still under experimental state. We have used titanium implant with or without TiO2 nanowires in a focal spinal cord injury and studies spinal cord pathology and motor function. In addition, we also combined with nanowired delivery of a potential neuroprotective drug DL-3-n-butylphthalide (DL-NBP) to the spinal cord in a rat model. Our observations show that a combination of titanium implant with nanowired delivery of DL-NBP induces superior neuroprotection and enhance motor functions after SCI. This treatment also restored blood-spinal cord barrier (BSCB) function and reduces edema formation and cell injury after SCI, not reports earlier.

Tail nerve electrical stimulation-induced walking training promotes restoration of locomotion and electrophysiology in rats with chronic spinal cord injury

Functional recovery is the final goal in the treatment of spinal cord injury. However, to date, few treatment strategies have demonstrated significant locomotor improvement in animal experiments. By using tail nerve electrical stimulation (TANES) as an open-field locomotor training method combined with glial scar ablation and cell transplantation, we have successfully promoted locomotor recovery in rats with chronic spinal cord contusion injury. The purpose of the present study is to further investigate the mechanism of TANES and its effect on electrophysiology. Spinal cord segment T10 of female, adult Long-Evans rats was contused using the NYU impactor device with 25 mm height setting. After injury, rats were randomly divided into three groups. Group I was used as a control without any treatment, group II and group III were subjected to basic treatment including glial scar ablation and transplantation of olfactory lamina propria 6 weeks after injury, and group III received TANES-induced open-field locomotor training weekly after basic treatment. All animals were allowed to survive 22 weeks, except some rats which were transected. Basso, Beattie, and Bresnahan (BBB) open-field locomotor rating scale, horizontal ladder rung walking test, and electrophysiological tests were used to assess the restoration of functional behavior and conduction. Results showed that TANES significantly improves locomotor recovery and spinal cord conduction, reflex, as well as significantly reduces the occurrence of autophagia. Additionally, after transection, trained rats still maintained higher BBB score than that of control rats. This may be related to the activity-dependent plasticity promoted by TANES-induced locomotor training.

Assessing structure and function of myelin in cervical spondylotic myelopathy: Evidence of demyelination.

To assess the extent of demyelination in cervical spondylotic myelopathy (CSM) using myelin water imaging (MWI) and electrophysiologic techniques. Somatosensory evoked potentials (SSEPs) and MWI were acquired in 14 patients with CSM and 18 age-matched healthy controls. MWI was performed on a 3.0T whole body magnetic resonance scanner. Myelin water fraction (MWF) was extracted for the dorsal columns and whole cord. SSEPs and MWF were also compared with conventional MRI outcomes, including T2 signal intensity, compression ratio, maximum spinal cord compression (MSCC), and maximum canal compromise (MCC). Group analysis showed marked differences in T2 signal intensity, compression ratio, MSCC, and MCC between healthy controls and patients with CSM. There were no group differences in MWF and SSEP latencies. However, patients with CSM with pathologic SSEPs exhibited reduction in MWF (p < 0.05). MWF was also correlated with SSEP latencies. Our findings provide evidence of decreased myelin content in the spinal cord associated with impaired spinal cord conduction in patients with CSM. While conventional MRI are of great value to define the extent of cord compression, they show a limited correlation with functional deficits (i.e., delayed SSEPs). MWI provides independent and complementary readouts to spinal cord compression, with a high specificity to detect impaired conduction.

Orthopaedic and Neurologic Aspects of Early Coxarthrosis Development in Children with Hip Dysplasia

Comparison of clinical-roentgenologic and electroneuromyographic data was performed for 29 patients, aged 3 - 16 years, at different stages of conservative and surgical treatment for hip joints dysplasia. First group included 18 patients with complicated clinical course; second - 11 patients with favorable process of joint formation. Functional activity of motor neurons, spinal cord and peripheral nerves conductivity was assessed. It was shown that in patients from the 1 st group the ENMG indices were statistically significantly lower than in healthy children ( р <0,05). F-waves parameters were typical for the change in spinal cord motor neurons activity of both functional and organic pattern. Decrease in the latent period of F-waves was indicative of axonal demyelinating lesion of spinal cord roots and peripheral nerves. Dynamic control at different stages of treatment showed negative changes in electrophysiological indices in complicated clinical course that confirmed the necessity of neurophysiologic monitoring.

Orthopaedic and Neurologic Aspects of Early Coxarthrosis Development in Children with Hip Dysplasia

Comparison of clinical-roentgenologic and electroneuromyographic data was performed for 29 patients, aged 3 - 16 years, at different stages of conservative and surgical treatment for hip joints dysplasia. First group included 18 patients with complicated clinical course; second - 11 patients with favorable process of joint formation. Functional activity of motor neurons, spinal cord and peripheral nerves conductivity was assessed. It was shown that in patients from the 1st group the ENMG indices were statistically significantly lower than in healthy children ( р

Effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration after spinal cord injury in rats.

[Purpose] The aim of this study was to evaluate the effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration in rats with spinal cord injury. [Subjects and Methods] A rat model of spinal cord injury was constructed by using the Allen weight-drop method. These rats were randomly divided into normal, spinal cord injury, and spinal cord injury + oscillating electrical field stimulation groups. The experimental group received the intervention with oscillating electrical field stimulation, and the control group received the intervention with an electrical field stimulator without oscillating electrical field stimulation. Each group was then randomly divided into seven subgroups according to observation time (1, 2, 4, 6, 8, 10, and 12 weeks). Basso-Beattie-Bresnahan score and inclined plate test score evaluation, motor evoked potential detection, and histological observation were performed. [Results] In the first 2 weeks of oscillating electrical field stimulation, the oscillating electrical field stimulation and inclined plate test scores of spinal cord injury group and spinal cord injury + oscillating electrical field stimulation group were not significantly different. In the fourth week, the scores of the spinal cord injury group were significantly lower than those of the spinal cord injury + oscillating electrical field stimulation group. The motor evoked potential incubation period in the spinal cord injury + oscillating electrical field stimulation group at the various time points was shorter than that in the spinal cord injury group. In the sixth week, the relative area of myelin in the spinal cord injury + oscillating electrical field stimulation group was evidently larger than that in the spinal cord injury group. [Conclusion] Oscillating electrical field stimulation could effectively improve spinal cord conduction function and promote motor function recovery in rats with spinal cord injury, as well as promote myelin regeneration.

Effect of nitric oxide on spinal evoked potentials and survival rate in rats with decompression sickness.

Nitric oxide (NO) releasing agents have, in experimental settings, been shown to decrease intravascular nitrogen bubble formation and to increase the survival rate during decompression sickness (DCS) from diving. The effect has been ascribed to a possible removal of preexisting micronuclei or an increased nitrogen washout on decompression through augmented blood flow rate. The present experiments were conducted to investigate whether a short- or long-acting NO donor [glycerol trinitrate (GTN) or isosorbide-5-mononitrate (ISMN), respectively] would offer the same protection against spinal cord DCS evaluated by means of spinal evoked potentials (SEPs). Anesthetized rats were decompressed from a 1-h hyperbaric air dive at 506.6 kPa (40 m of seawater) for 3 min and 17 s, and spinal cord conduction was studied by measurements of SEPs. Histological samples of the spinal cord were analyzed for lesions of DCS. In total, 58 rats were divided into 6 different treatment groups. The first three received either saline (group 1), 300 mg/kg iv ISMN (group 2), or 10 mg/kg ip GTN (group 3) before compression. The last three received either 300 mg/kg iv ISMN (group 4), 1 mg/kg iv GTN (group 5), or 75 μg/kg iv GTN (group 6) during the dive, before decompression. In all groups, decompression caused considerable intravascular bubble formation. The ISMN groups showed no difference compared with the control group, whereas the GTN groups showed a tendency toward faster SEP disappearance and shorter survival times. In conclusion, neither a short- nor long-acting NO donor had any protective effect against fatal DCS by intravenous bubble formation. This effect is most likely due to a fast ascent rate overriding the protective effects of NO, rather than the total inert tissue gas load.

Effects of Cilostazol on Oxidative Stress, Systemic Cytokine Release, and Spinal Cord Injury in a Rat Model of Transient Aortic Occlusion

Cilostazol is a phosphodiesterase inhibitor that has anti-inflammatory potential in addition to vasodilator and antiplatelet effects. The aim of this study was to determine the influence of cilostazol on biochemical markers of oxidative damage, proinflammatory cytokine release, and spinal cord injury after transient aortic occlusion in rats. Animals were randomized into 3 groups. Sham group rats were subjected to laparotomy without aortic occlusion. Control group rats were pretreated with intraperitoneal dimethyl sulfoxide, and cilostazol group rats received intraperitoneal cilostazol (20 mg/kg/day) for 3 days before the induction of ischemia. Ischemia was induced by clamping of the infrarenal aorta, and 48 hours after reperfusion, Tarlov grades were assessed and spinal cord conduction velocities (SCCVs) were measured using epidural electrical stimulation. Erythrocyte superoxide dismutase (SOD) and catalase activities and plasma malondialdehyde, serum tumor necrosis factor-α, interleukin-1β, and interleukin-6 levels were analyzed. Spinal cord histopathology was examined to determine neuronal damage and tissue inflammation. Aortic occlusion caused significant increases in SOD, catalase activities, and malondialdehyde and cytokine levels accompanied by spinal cord injury. Cilostazol significantly reduced malondialdehyde levels but did not significantly alter the activations of antioxidant enzymes, levels of proinflammatory cytokines, or histologic severity of inflammation. The differences regarding the results of Tarlov grading, SCCVs, and neuronal viability between the ischemic and cilostazol pretreated groups were statistically nonsignificant. The present experimental study indicated that cilostazol pretreatment used in this study before aortic occlusion decreased lipid peroxidation, which may be related to the reduction of reactive oxygen species. Cilostazol did not significantly suppress systemic cytokine release and prevent spinal cord inflammation and injury; however, it did show some benefit. Additional investigations might be needed to determine the critical dose of cilostazol for clarifying the protective role of this drug in spinal cord ischemia/reperfusion injury.

Informativeness of neurophysiological diagnostic methods in the differentiation of motor neurons of spinal cord motor neuron disease

Objectives: Defining the principles and tactics of differential use of Neurophysiological (NPh) methods in cervical spondilotic myelopathy (CSM) diagnosis.Materials and methods. Analysis of the clinical and NPh examination data of 160 patients (from 31 to 76 years of age) suffering from CSM. The examination techniques used: clinical and neurological; neurovisualizing (MRI, CT, functional spondylography); a set of NPh methods, namely: stimulation electromyography (ENMG) with F-wave recording (188 examinations); needle EMG (105); motor evoked potentials (MEP) (188); somatosensory evoked potentials (SSEP) (50); single fiber EMG with determination of average density of muscle fibers in motor units and reliability of neuromuscular transmission (32).Results. An optimal scheme of the use of NPh diagnostic methods in patients with SCM was worked out and applied. Out of the total of 160 patients examined, 19 (11.9%) had motoneuron involved; 32 (20%) had ALS syndrome at the background of cervical spondylosis; 59 (36.9%) patients had concomitant radiculopathy, etc. The sensitivity of MEP technique in the identification of partial spinal cord compression in cervical spondylosis was confirmed – 134 (83.8%) cases; SSEP – 29 (58%). The clinical example illustrates the role of jitter-analysis in the cases when a subtle differentiation between the motoneuronal disease, ischemic and compression injury of the spinal cord motoneurons is necessary.Conclusions. An optimal scheme of the use of NPh diagnostic methods in patients with CSM was suggested. Due to the use of motor and somatosensory evoked potential techniques, the diagnosis of the spinal cord conduction structures compression and evaluation of the degree of their functional disorders were improved. The use of jitter-analysis allows to increase the information value of NPh diagnosis of the spinal motoneuron involvment, especially at the early stages of the pathological process.