• 대한통합의학회지
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• 제7권4호
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• pp.131-140
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• 2019

Purpose : The purpose of this study was to investigate the interrelationship between eye movement and auditory function through the effects of eye lateralization on transient evoked otoacoustic emissions of auditory function. Methods : 25 subjects with complete set of ears were used in this study, which composed of 12 males and 13 females with pure tone threshold of below 25 dB without otolaryngology were evaluated. Each of the patient has a visual acuity of greater than 1.0 after correction, and has no problems with eye disease, eye movement, and human parallel system. In a dark silent room, the subjects sat on a chair with their heads fixed on a headrest. The tests were performed by asking the patients to look at a fixed red light dot on a light bar in front of them. This light was directed to the front, right and left sides of the subject at an angle of 40 ° In the presence of the stimulus sound in the ipsilateral ear, the transient evoked otoacoustic emissions of the ipsilateral ear was measured at the straight, right and left fixation. In order to evaluate the transient evoked otoacoustic emissions through the efferent auditory pathway, the transient evoked otoacoustic emission values of the contralateral ear were measured at the straight, right and left fixation. These measurements were taken at frequencies of 1 kHz, 1.4 kHz, 2.0 kHz, 2.8 kHz and 4 kHz, respectively. Results : Transient evoked otoacoustic emissions caused by lateral movement of the eye showed significant changes at 1.4 KHz and 2 KHz of the afferent pathway of the ipsilateral ear. Also, significant changes were observed at 1.4 KHz and 4 KHz of the efferent pathway of the contralateral ear. Conclusion : These results indicated that there is a close relationship between eye movement and auditory cochlea. In the future, further studies considering more diverse subjects and age groups will be needed.

• The Journal of Korean Physical Therapy
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• 제26권3호
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• pp.216-219
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• 2014

Purpose: We presented with a patient with traumatic brain injury who showed a transcallosal ipsilateral motor pathway from unaffected motor cortex to affected extremities, as evaluated by diffusion tensor tractography (DTT). Methods: One patient and six age-matched normal subjects were enrolled. A 42-year-old left hemiparetic male who suffered from brain injury by motor vehicle accident 9 years ago showed a leukomalactic lesion in the right corona radiata and parieto-temporal lobe. His left extremities were completely paralyzed initially, but recovered slowly over 2 years. At the time of the evaluation, he was able to grasp and release an object, and to walk with spastic gait pattern. DTT was performed using 1.5 T with a Synergy-L Sensitivity Encoding head coil. DTT was obtained with termination criteria of FA <0.2 and an angle change > $45^{\circ}c$. Results: The motor tracts of the unaffected (left) hemisphere of the patient and control subjects originated from the motor cortex and descended along the known corticospinal tract without any transcallosal tract. By contrast, the tract of the affected (right) hemisphere originated from the left premotor cortex, descended through the left corona radiata, and then crossed the mid-portion of the corpus callosum. The tract then descended through the known corticospinal tract pathway to the right medulla. Conclusion: We conclude that the transcallosal ipsilateral motor pathway from the unaffected hemisphere appeared to contribute to the motor recovery in this patient.

• 한국의학물리학회지:의학물리
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• 제18권1호
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• pp.42-47
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• 2007

목적: 망간 조영증강 자기공명영상을 이용하여 시신경경로의 활성화를 추적해 보고자 하였다. 대상 및 방법: 뉴질랜드 암컷 흰색 토끼의 망막에 $30{\mu}l$의 $MnSl_2(1mol)$ 용액을 주입한 후 고성능 경사자계 시스템이 장착된 임상용 1.5 기기에서 3D FSPGR 펄스열을 사용하여 고해상도 T1-강조영상을 망간 주입 후 12시간, 24시간, 48시간에 각각 획득한 후 시신경경로의 주요 해부학적 구조물에서의 조영증강을 관찰하였다. 또한 정량적 평가를 위하여 해부학적 위치에 동일한 원형의 관심영역을 정하여 신호강도를 측정 한 후 배경 잡음의 신호강도와의 신호대 잡음비(signal-to-noise ratio)를 구하였다. 결과: 망간 주입 후 시신경 경로상의 주요 구조물들이 조영증강 되었다 조영 증강된 주요 구조물로는 오른쪽 시신경(optic nerve), 시각교차(optic chiasm), 왼쪽 시신경 경로(optic tract), 왼쪽 가쪽 무릎핵(lateral geniculate nucleus), 왼쪽 상구(superior colliculus) 등 오른쪽 망막의 대측(contralateral) 시신경 경로상의 구조물이었으며 동측(ipsilateral) 시신경 경로는 조영증강을 보이지 않았다. 결론: 시신경계의 말단부위인 망막에 $MnCl_2$를 주입한 후 시신경계의 축삭을 통한 망간이온의 전파를 비침습적으로 관찰 할 수 있었다. 이러한 망간이온의 전파는 전압 개폐성 칼슘채널을 통하여 일어나는 것으로 여겨지며 특히 망막에 직접 주입하는 경우 전압 개폐성 칼슘채널의 빠른 이동 경로를 이용하는 것으로 추측된다.

• 대한중풍순환신경학회지
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• 제8권1호
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• pp.48-57
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• 2007

Stroke is a disease which results in impairment of body functions and affects everyday life. The ability of cerebral neurons to become reorganized and restore function after damage is called plasticity. Motor impairment typically appears contralateral to the affected cerebral hemisphere in patients with cerebral lesions. The authors report a case of a patient with hemiplegia ipsilateral to affected cerebral hemisphere, along with its conjectured mechanism.

• Journal of Microbiology and Biotechnology
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• 제32권9호
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• pp.1168-1177
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• 2022

Parkinson's disease (PD) is the second-most prevalent neurodegenerative disease and is characterized by dopaminergic neuronal death in the midbrain. Recently, the association between alterations in PD pathology and the gut microbiota has been explored. Microbiota-targeted interventions have been suggested as a novel therapeutic approach for PD. Agathobaculum butyriciproducens SR79^T (SR79) is an anaerobic bacterium. Previously, we showed that SR79 treatment induced cognitive improvement and reduced Alzheimer's disease pathologies in a mouse model. In this study, we hypothesized that SR79 treatment may have beneficial effects on PD pathology. To investigate the therapeutic effects of SR79 on PD, 6-hydroxydopamine (6-OHDA)-induced mouse models were used. D-Amphetamine sulfate (d-AMPH)-induced behavioral rotations and dopaminergic cell death were analyzed in unilateral 6-OHDA-lesioned mice. Treatment with SR79 significantly decreased ipsilateral rotations induced by d-AMPH. Moreover, SR79 treatment markedly activated the AKT/GSK3β signaling pathway in the striatum. In addition, SR79 treatment affected the Nrf2/ARE signaling pathway and its downstream target genes in the striatum of 6-OHDA-lesioned mice. Our findings suggest a protective role of SR79 in 6-OHDA-induced toxicity by regulating the AKT/Nrf2/ARE signaling pathway and astrocyte activation. Thus, SR79 may be a potential microbe-based intervention and therapeutic strategy for PD.

• Journal of Ginseng Research
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• 제47권2호
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• pp.274-282
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• 2023

Background: Ginsenoside compound K (CK) stimulated activation of the PI3K-Akt signaling is one of the major mechanisms in promoting cell survival after stroke. However, the underlying mediators remain poorly understood. This study aimed to explore the docking protein of ginsenoside CK mediating the neuroprotective effects. Materials and methods: Molecular docking, surface plasmon resonance, and cellular thermal shift assay were performed to explore ginsenoside CK interacting proteins. Neuroscreen-1 cells and middle cerebral artery occlusion (MCAO) model in rats were utilized as in-vitro and in-vivo models. Results: Ginsenoside CK interacted with recombinant human PTP1B protein and impaired its tyrosine phosphatase activity. Pathway and process enrichment analysis confirmed the involvement of PTP1B and its interacting proteins in PI3K-Akt signaling pathway. PTP1B overexpression reduced the tyrosine phosphorylation of insulin receptor substrate 1 (IRS1) after oxygen-glucose deprivation/reoxygenation (OGD/R) in neuroscreen-1 cells. These regulations were confirmed in the ipsilateral ischemic hemisphere of the rat brains after MCAO/R. Ginsenoside CK treatment reversed these alterations and attenuated neuronal apoptosis. Conclusion: Ginsenoside CK binds to PTP1B with a high affinity and inhibits PTP1B-mediated IRS1 tyrosine dephosphorylation. This novel mechanism helps explain the role of ginsenoside CK in activating the neuronal protective PI3K-Akt signaling pathway after ischemia-reperfusion injury.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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• pp.104-104
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• 2001

Purpose： In this study, we investigated the possible motor pathways of hemiplegic stroke patients usin combined TMS and BOLD fMRI approach and evaluated the correlation between TMS a fMRI methods. Method： Four subjects, who demonstrated left hemiplegia after stroke, are included. TMS was performed using a Dantec Mag2 stimulator (Dantec Company, USA) in single puls mode with figure eight-shaped coil. Following TMS localization, The BOLD T2＊-weight images were acquired with echo planar imaging sequence (TR = 1.2 sec, TE = 60 msec, and flip angle = 90). Motor activation was studied by means of a repetitive fing flexion-extension task. The stimulation protocol comprised 10 cycles of alternating activati and rest (10 images per cycle). Total 60 cycles were performed and each cycle take abou 1.5 sec. The resulting images were then analyzed with STIMULATE (CMRR, U, o Minnesota) to generate functional maps using a student t-test (p < 0.0005) and cluste analysis.

• Animal cells and systems
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• 제4권4호
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• pp.353-359
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• 2000

Location of the neurons in the lateral reticular nucleus projecting to dorsal horn of the cervical, thoracic, or lumbar spinal cord was investigated in the rat using the technique of retrograde transport of horseradish peroxidase. The projection was bilateral with ipsilateral predominance. Neurons projecting to the cervical spinal cord were located near the medial, dorsal, and lateral perimeter of the magnocellular division of the lateral reticular nucleus, whereas cells projecting to the thoracic and lumbar spinal cord were localized in the medial and dorsal boundaries of the magnocellular division. The labeled neurons were distinctly multipolar in shape and measured approximately 10-15 $\mu m$ in their greatest transverse diameter. A few neurons were also observed in the subtrigeminal nucleus, whereas few cells were in the parbocellular division. These observations provide an anatomical substrate for the functional implication of the lateral reticular nucleus in the regulation of spinal nociceptive transmission and vascular hemodynamics via the descending pathway into the spinal cord.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.831-841
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• 2001

Objective : Somatosensory evoked potentials(SSEPs) have been used widely both experimentally and clinically to monitor the function of central nervous system and peripheral nervous system. Studies of SSEPs have reported the various recording techniques and patterns of SSEP. The previous SSEP studies used scalp recording electrodes, showed mean vector potentials which included relatively constant brainstem potentials(far-field potentials) and unstable thalamocortical pathway potentials(near-field potentials). Even in invasive SSEP recording methods, thalamocortical potentials were variable according to the kinds, depths, and distance of two electrodes. So they were regarded improper method for monitoring of upper level of brainstem. The present study was conducted to investigate the characteristics of somatosensory evoked field potentials(SSEFPs) of the cerebral cortex that evoked by hindlimb stimulation using ball electrode and the pathways of SSEFP by recording the potentials simultaneously in the cortex, VPL nucleus of thalamus, and nucleus gracilis. Methods : In the first experiment, a specially designed recording electrode was inserted into the cerebral cortex perpendicular to the cortical surface in order to recording the constant cortical field potentials and SSEFPs mapped from different areas of somatosensory cortex were analyzed. In the second experiment, SSEPs were recorded in the ipsilateral nucleus gracilis, the contralateral ventroposterolateral thalamic nucleus(VPL), and the cerebral cortex along the conduction pathway of somatosensory information. Results : In the first experiment, we could constantly obtain the SSEFPs in cerebral cortex following the transcutaneous electrical stimulation of the hind limb, and it revealed that the first large positive and following negative waves were largest at the 2mm posterior and 2mm lateral to the bregma in the contralateral somatosensory cortex. The second experiment showed that the SSEPs were conducted by way of posterior column somatosensory pathway and thalamocortical pathway and that specific patterns of the SSEPs were recorded from the nucleus gracilis, VPL, and cerebral cortex. Conclusion : The specially designed recording electrode was found to be very useful in recording the localized SSEFPs and the transcutaneous electrical stimulation using ball electrode was effective in evoking SSEPs. The characteristic shapes, latencies, and conduction velocities of each potentials are expected to be used the fundamental data for the future study of brain functions, including the hydrocephalus model, middle cerebral artery ischemia model, and so forth.

• Journal of Korean Neurosurgical Society
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• 제29권8호
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• pp.985-994
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• 2000

Objective : There are some advantages of trigeminal evoked potential(TEP) recording compared to other somatosensory evoked potential(SSEP) recordings. The trigeminal sensory pathway has a pure sensory nerve branch, a broader receptive field in cerebral cortex, and a shorter pathway. Despite these advantages, there is little agreement as to what constitutes a normal response and what wave forms truly characterize the intraoperative TEP. This study presents the normative data of TEP recorded on the epidural surface of the rat with a platinum ball electrode. Materials & Methods : Under general anesthesia with urethane, the adult Sprague-Dawley male rats(300-350g) were given electrical stimulation with two stainless steel electrodes which were inserted into the subcutaneous layer of the area around whiskers. A reference electrode was positioned in the temporalis muscle ipsilateral to the recording site. Results : TEPs were recorded in the Par I area of somatosensory cortex and recorded most apparently on the point of 2mm posterior from the bregma and 6mm lateral from the midline. The typical wave form consisted of 5 peaks (N1-P1-N2-P2-N3 according to emerging order, upward negativity). Each latency to corresponding peaks was not influenced by the different intensities of stimulation, especially from 1 to 5mA. Average latencies of 5 peaks were in the following order ; 7.7, 11.1, 15, 22.3, 29.4ms. There was also no significant difference between latencies before and after administration of muscle relaxant(pancuronium). For the electrophysiological localization of recorded waves, the action potential of a single unit was recorded with glass microelectrode(filled with 2M NaCl, $3-5M{\Omega}$) in the thalamus of rat. A sharp wave was recorded in the VPM nucleus, in which the latency was shorter than that of N1. This suggests that all 5 peaks were generated by neural activities in the suprathalamic pathway. Conclusion : In terms of recording near-field potentials, our data also suggests that TEP in the rat may be superior to other SSEPs. In overall, these results may afford normative data for the studies of supratentorial lesions such as hydrocephalus or cerebral ischemia which can have an influence on near-field potentials.