• Journal of Oral Medicine and Pain
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• v.46 no.4
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• pp.136-142
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• 2021

Purpose: Oral and facial sensation is affected by various factors, including trauma and disease. This study assessed the clinical profile of patients diagnosed with sensory dysfunction and investigated their sensory perception using simple qualitative sensory tests. Methods: Based on a retrospective review of the medical records, we analyzed a total of 68 trigeminal nerve branches associated with sensory dysfunction in 52 subjects. We analyzed the frequency and etiology of sensory dysfunction, and the frequency of different types of sensory perception in response to qualitative sensory testing using tactile and pin-prick stimuli. Results: The inferior alveolar nerve branch was the most frequently involved in sensory dysfunction (88.5%). Third molar extraction (36.5%) and implant surgery (36.5%) were the most frequent etiological factors associated with sensory dysfunction. Hypoesthesia was the most frequent sensory response to tactile stimuli (60.3%). Pin-prick stimuli elicited hyperalgesia, hypoalgesia, and analgesia in 32.4%, 27.9%, and 36.8%, respectively. A significant association was found between the two kinds of stimuli (p=0.260). Conclusions: Sensory dysfunction frequently occurs in the branches of the trigeminal nerve, including the inferior alveolar nerve, mainly due to trauma associated with dental treatment. Simple qualitative sensory testing can be conveniently used to screen sensory dysfunction in patients with altered sensation involving oral and facial regions.

• Journal of Korean Neurosurgical Society
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• v.40 no.6
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• pp.401-405
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• 2006

Objective : Electrodiagnostic test has shown diagnostic sensitivity and specificity in carpal tunnel syndrome[CTS]. This study was to evaluate the correlation between clinical outcome of endoscopic carpal tunnel ligament release[ECTR] and the predictive value of sensory nerve conduction. Methods : From January 1998 to December 2004, 87 patients [44 right hand, 37 left hand, 6 bilateral hands] with CTS who underwent ECTR were followed up in our hospital for an average of 24 months. We retrospectively analyzed the results with previous medical records. All patients underwent electrodiagnostic test and ECTR. The patients were divided into three groups according to the electrodiagnostic test results. Group [A] was normal sensory nerve response, Group [B] was slowing sensory response and Group [C] was no sensory response. Improvement of the symptom after ECTR was assessed using a visual analogue scale[VAS] score. Results : Differences between the three groups on the correlation of severity of sensory potential and duration of preoperative symptoms were significant. The mean value of improved VAS scores for the three groups were $6.0{\pm}0.96$ in the Group A, $6.11{\pm}0.48$ in the Group B and $6.14{\pm}0.53$ in the Group C. There was no statistically significant difference between the severity of sensory nerve response and improvement in VAS score after ECTR. Complications included a wound infection, a case of skin necrosis, and two patients with persistent symptoms without any improvement. Conclusion : Although electrodiagnostic test has been known to be useful, sensory nerve response is considered not to be a good prognostic value for carpal tunnel syndrome after ECTR.

• Annals of Clinical Neurophysiology
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• v.7 no.2
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• pp.97-100
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• 2005

Background: The most distal sensory fibers of the feet are often affected first in polyneuropathy. However, they are not evaluated in routine nerve conduction studies. Thus we evaluated the dorsal sural sensory nerve in patients with sensorimotor polyneuropathy with normal sural response, in order to assess the usefulness in electrodiagnostic practice. Methods: In this study, 53 healthy subjects and 27 patients with clinical evidence of sensorimotor polyneuropathy were included. In all subjects, peripheral motor and sensory nerve studies were performed on the upper and lower limbs including dorsal sural nerve conduction studies. On electrodiagnostic testing, all patients had normal sural responses. Results: The dorsal sural sensory nerve action potentials (SNAPs) mean amplitude was $13.12{\pm}5.68{\mu}V$, mean latency was $3.12{\pm}0.43msec$, and mean sensory conduction velocity (SCV) was $36.50{\pm}3.40m/s$ in healthy subjects. In 7 of 27 patients, the dorsal sural nerve SNAPs were absent bilaterally, and in 20 patients, the mean dorsal sural nerve distal latency was longer($3.40{\pm}0.48ms$, P=0.006), and mean SCV was slower than in healthy subjects($35.08{\pm}4.59$, P=0.043). However, dorsal sural nerve amplitude was not different between the groups (P=0.072). Conclusions: Our findings suggest that dorsal sural nerve conduction studies should be included in the routine electrodiagnostic evaluation of patients with suspected polyneuropathy and normal sural nerve responses.

• Electronics and Telecommunications Trends
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• v.38 no.6
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• pp.62-74
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• 2023

In response to diverse external stimuli, sensory receptors generate spiking nerve signals. These generated signals are transmitted to the brain along the neural pathway to advance to the stage of recognition or perception, and then they reach the area of discrimination or judgment for remembering, assessing, and processing incoming information. We review research trends in neuromorphic sensory perception technology inspired by biological sensory perception functions. Among the various senses, we consider sensory nerve decoding technology based on sensory nerve pathways focusing on touch and smell, neuromorphic synapse elements that mimic biological neurons and synapses, and neuromorphic processors. Neuromorphic sensory devices, neuromorphic synapses, and artificial sensory memory devices that integrate storage components are being actively studied. However, various problems remain to be solved, such as learning methods to implement cognitive functions beyond simple detection. Considering applications such as virtual reality, medical welfare, neuroscience, and cranial nerve interfaces, neuromorphic sensory recognition technology is expected to be actively developed based on new technologies, including combinatorial neurocognitive cell technology.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.37-43
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• 1991

The nerve impulse pattern of Chorda tympani(CT) of cat was tested with Monosodium glutamate(MSG) solutions as well as some basic taste substances applied on the tongue of cat. The effect of MSG applied in the tongue prior to the stimulation of other taste substances was also investigated. The response impulse frequency of CT of cat was changed by the kind and concentration of taste substances. The response to citric acid was the highest among the tested substances, NaCl, KCl and MSG showed similar responses. When different concentrations of MSG were applied on the tongue prior to other substances, the response to NaCl increased with the maximum response at the MSG concentration of 0.02 M. The response to sucrose tended to be reduced, but the response to citric acid was distinctly supressed by the previous MSG stimulation. These results were well consistent with the sensory evaluation on the effect of MSG to some basic taste substances. previously reported by the authors.

• The Journal of Internal Korean Medicine
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• v.33 no.2
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• pp.126-144
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• 2012

Background : Peripheral nerves more rapidly recover than central nerves. However, it has been known that the degree of reaction of axons of peripheral nerves is affected by distinctive characteristics of axons and environmental factors near the axons. Taxol is a widely used medicine as for ovarian, breast, lung and gastric cancer. However it causes patients difficulties under treatment due to its toxic and side effects, which include persistent pain. Objectives : This study reviewed how SJT extract in vitro and in vivo affects nerve tissues of a sciatic nerve damaged by Taxol. It also studied how SJT extract in vivo affects axons of the sciatic nerve after the sciatic nerve was damaged by pressing. Methods : After vehicle, Taxol, and Taxol plus SJT were treated respectively for tissue of the sciatic nerve in vitro and then tissues were observed using Neurofilament 200, Hoechst, ${\beta}$-tubulin, $S100{\beta}$, caspase-3 and anti-cdc2. SJT was also oral medicated by injecting Taxol into the sciatic nerve of in vivo rats. Tissues of the sciatic nerve and axons of DRG sensory nerves were then observed using Neurofilament 200, Hoechst, ${\beta}$-tubulin, $S100{\beta}$, caspase-3 and p-Erk1/2. After inflicting pressing damage to the sciatic nerve of in vivo rats, tissues of the sciatic nerve and DRG sensory nerve were observed using Neurofilament 200, Hoechst, $S100{\beta}$, caspase-3, anti-cdc2, phospho-vimentin, ${\beta}1$-integrin, Dil reverse tracking and p-Erk1/2. Results : The group of in vitro Taxol plus SJT treatment had meaningful effects after sciatic nerve tissue was damaged by Taxol. The group of in vivo SJT treatment had effects of regenerating Schwann cells and axons which were damaged by Taxol treatment. The group of in vivo SJT had effects of regenerating axons in damaged areas after the sciatic nerve was damaged by pressing, and also had variations of distribution in Schwann cells at DRG sensory nerves and axons. Conclusions : This study confirmed that SJT treatment is effective for growth of axons in the sciatic nerve tissues and improvement of Schwann cells after axons of the sciatic nerve tissues was damaged. After tissues of sciatic nerve was damaged by pressing in vivo, SJT treatment had effects on promoting regeneration of axon in the damaged area and reactional capabilities in axons of DRG sensory nerves.

• The Korean Journal of Physiology
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• v.30 no.2
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• pp.289-297
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• 1996

Excitatory amino acids (EAA) are thought to play an important role in producing cell death associated with ischemic and traumatic spinal cord injury. The present study was carried out to determine if the response characteristics of spinal sensory neurons in segments adjacent to degeneration sites induced by EAA are altered following these morphological changes. Intraspinal injections of quisqualic acid (QA) produced neuronal degeneration and spinal cavitation of gray matter. The severity of lesions was significantly attenuated by pretreatment with a non-NMDA antagonist NBQX. In extracellular single unit recordings, dorsal horn neurons in QA injected animal showed the increased mechanosensitivity, which included a shift to the left in the stimulus-response relationship, an increased background activity and an increase in the duration of after-discharge responses. Neuronal responses, especially the C-fiber response, to suprathreshold electrical stimulation of sciatic nerve also increased in most cases. These results suggest that altered functional states of neurons may be responsible for sensory abnormalities, e.g. allodynia and hyperalgesia, associated with syringomyolia and spinal cord injury.

• Annals of Clinical Neurophysiology
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• v.19 no.1
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• pp.34-39
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• 2017

Background: Automated nerve excitability testing is used to assess various peripheral neuropathies and motor neuron diseases. Comparing these excitability parameters with normal data provides information regarding the axonal excitability properties and ion biophysics in diseased axons. This study measured and compared normal values of axonal excitability parameters in both the distal motor and sensory axons of normal Koreans. Methods: The axonal excitability properties of 50 distal median motor axons and 30 distal median sensory axons were measured. An automated nerve excitability test was performed using the QTRACW threshold-tracking software (Institute of Neurology, University College London, London, UK) with the TRONDF multiple excitability recording protocol. Each parameter of stimulus-response curves, threshold electrotonus, current-voltage relationship, and recovery cycle was measured and calculated. Results: Our Korean normal data on axonal excitability showed ranges of values and characteristics similar to previous reports from other countries. We also reaffirmed that there exist characteristic differences in excitability properties between motor and sensory axons: compared to motor axons, sensory axons showed an increased strength-duration time constant, more prominent changes in threshold to hyperpolarizing threshold electrotonus (TE) and less prominent changes in threshold to depolarizing TE, and more prominent refractoriness and less prominent subexcitability and superexcitability. Conclusions: We report normal data on axonal excitability in Koreans. These data can be used to compare various pathological conditions in peripheral nerve axons such as peripheral neuropathies and motor neuron disease.

• YAKHAK HOEJI
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• v.41 no.1
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• pp.139-146
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• 1997

In the present study, capsaicin-induced desensitization of peripheral sensory nerves were investigated by using guinea pig bronchi, in which these nerves are stimulated with cap saicin to produce a contractile response via the release of sensory neuropeptides such as substance P and neurokinin A. The contractile response to capsaicin was inhibited by the combination of CP96345 and SR 48968 suggesting that the excitatory effect of capsaicin is mediated via both the tachykinin NK-1 and NK-2 receptor. Capsaicin produced in vitro-desensitization in dose-dependent manner, but after this in vitro-desensitization the response to NK-1 and NK-2 receptor agonist did not change. Systemic administration (s.c.) of capsaicin also desensitized significantly bronchial tissues but could not produce any change in the contractile response to the selective agonists of NK-1 and NK-2 receptor. Therefore, the present results suggest that functional desensitization to capsaicin-induced contractile response in guinea pig bronchi does not involve NK-1 and NK-2 receptor, while excitatory effect of capsaicin is mediated via both NK-1 and NK-2 receptor. In conclusion, it is suggested that capsaicin- induced excitation and desensitization involves somewhat different pathways.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.101-121
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• 2000

The purpose of this morphological studies was to investigate the relation to the meridian, acupoint and nerve. The common locations of the spinal cord and brain projecting to the the gallbladder, GB34 and common peroneal nerve were observed following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV), into the gallbladder, GB34 and common peroneal nerve of the rabbit. After survival times of 96 hours following injection of PRV, the thirty rabbits were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by PRV immunohistochemical staining method, and observed with light microscope. The results were as follows: 1. In spinal cord, PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in thoracic, lumbar and sacral spinal segments. Densely labeled areas of each spinal cord segment were founded in lamina V, VII, X, intermediolateral nucleus and dorsal nucleus. 2. In medulla oblongata, The PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in the A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nucleus, medullary reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus, gigantocellular nucleus, lateral paragigantocellular nucleus, principal sensory trigeminal nucleus and spinal trigeminal nucleus. 3. In Pons, PRV labeled neurons were parabrachial nucleus, Kolliker-Fuse nucleus and cochlear nucleus. 4. In midbrain, PRV labeled neurons were founded in central gray matter and substantia nigra. 5. In diencephalon, PRV labeled neurons were founded in lateral hypothalamic nucleus, suprachiasmatic nucleus and paraventricular hypothalamic nucleus. 6. In cerebral cortex, PRV labeled neuron were founded in hind limb area.This results suggest that PRV labeled common areas of the spinal cord projecting to the gallbladder, GB34 and common peroneal nerve may be first-order neurons related to the somatic sensory, viscero-somatic sensory and symapathetic preganglionic neurons, and PRV labeled common area of the brain may be first, second and third-order neurons response to the movement of smooth muscle in gallbladder and blood vessels.These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory system monitoring the internal environment, including both visceral sensation and various chemical and physical qualities of the bloodstream. The present morphological results provide that gallbladder meridian and acupoint may be related to the central autonomic pathways.