• The Korean Journal of Zoology
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• v.33 no.4
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• pp.454-460
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• 1990

The effed of acrylamide on the nervous system has heen morphologically studied using light and electron microscopes. The light micrographs on central and pedpheral nervous tissues of mouse treated with acrylamide monomer showed total vacuolation of spinal cord, cell degradation containing neuron and neuroglia, and distal nerve fiber degeneration. The electron micrographs showed ultrastrudural changes. Abnormal mitochondria in neuron, splitting of myelin sheath in lumbar ventral root nerve, partial disintergration of myelin sheath and axoplasmic degeneration in sciatic nerve, and overafl polyneuropathies in nervous system were observed. These results suggest that acrylarnide intoxicated mouse shows distal behavioral neuropathy as an earlist clinical sign, but the initial effect of acrylamide on the nervous system seems to appear at nearly the same time in both central and peripheral nervous systems.

• PNF and Movement
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• v.6 no.3
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• pp.37-51
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• 2008

Purpose : This paper focuses on the emerging concept that adult central nervous system neurogenesis can be regulated by various physical activity, enriched environment, and pathological conditions. Neurogenesis-the production of new neuron-is an ongoing process that persists in the adult brain of mammalian, including humans. Result : The adult brain was thought be limited in its regenerative function. However, this concepts changed, recent evidence of neurogenesis in certain adult brain areas such as SVZ(subventricular zone) and SGZ(subgranular zone) in hippocampus, raised possibility for improved treatment for patient with stroke. Neural plasticity has an adaptive purpose, because an ability of the brain to change in response to peripheral stimulation, physical activity, experience, and injury. Conclusions : The major function of the neurogenesis in adult brain seems to be replacing the neuron that die regularly in discrete adult brain regions. These cells are capable of functionally integrating into neighboring neural cells, and reconnecting to the correct neural networks. This review suggest that various intervention, including physical activity, voluntary movement training, skilled forelimb reaching training, and enriched environment, induced neural cell production in certain adult brain, and associated with functional recovery after stroke.

• Journal of Korean Biological Nursing Science
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• v.4 no.1
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• pp.101-112
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• 2002

Peripheral nerve injury results in plastic changes in the dorsal ganglia (DRG) and spinal cord, and is often complicated with neuropathic pain. The mechanisms underlying these changes are not known, but these changes seem to be most likely related to the neurotrophic factors. This study investigated the effects of mechanical peripheral nerve injury on expression of brain-derived neurotrophic factor(BDNF) in the DRG and spinal cord in rats. 1) Bennett model and Chung model groups showed significantly increased percentage of small, medium and large BDNF-immunoreactive neurons in the ipsilateral $L_4$ DRG compared with those in the contralateral side at 1 and 2 weeks of the injury. 2) In the ipsilateral $L_5$ DRG of the Chung model, percentage of medium and large BDNF-immunoreactive neurons increased significantly at 1 week, whereas that of large BDNF-immunoreactive neurons decreased at 2 week when compared with those in the contralateral side. The intensity of immunoreactivity of each neuron was lower in the ipsilateral than in the contralateral DRG. 3) In the spinal cord, the Bennett and Chung model groups showed a markedly increased BDNF-immunoreactivity in axonal fibers of both superficial and deeper laminae. The present study demonstrates that peripheral nerve injury in neuropathic models altered the BDNF expression in the DRG and spinal cord. This may suggest important roles of BDNF in sensory abnormalities after nerve injury and in protecting the large-sized neurons in the damaged DRG.

• The Korean Journal of Pain
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• v.13 no.1
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• pp.19-30
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• 2000

Background: Partial nerve injury to a peripheral nerve may induce the development of neuropathic pain which is characterized by symptoms such as spontaneous burning pain, allodynia and hyperalgesia. Though underlying mechanism has not fully understood, sensitization of dorsal horn neurons may contribute to generate such symptoms. Nitric oxide acts as an inter- and intracellular messenger in the nervous system and is produced from L-arginine by nitric oxide synthase (NOS). Evidence is accumulating which indicate that nitric oxide may mediate nociceptive information transmission. Recently, it has been reported that NOS inhibitor suppresses neuropathic pain behavior in an neuropathic pain animal model. This study was conducted to determine whether nitric oxide could be involved in the sensitization of dorsal horn neurons in neuropathic animal model. Methods: Neuropathic animal model was made by tightly ligating the left L5 and L6 spinal nerves and we examined the effects of iontophoretically applied NOS inhibitor (L-NAME) on the dorsal horn neuron's responses to mechanical stimuli within the receptive fields. Results: In normal animals, NOS inhibitor (L-NAME) specifically suppressed the responses to the noxious mechanical stimuli. In neuropathic animals, the dorsal horn neuron's responses to mechanical stimuli were enhanced and NOS inhibitor suppressed the dorsal horn neuron's enhanced responses to non-noxious stimuli as well as those to noxious ones. Conclusions: These results suggest that nitric oxide may mediate nociceptive transmission in normal animal and also mediate sensitization of dorsal horn neurons in neuropathic pain state.

• Journal of KIISE:Information Networking
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• v.29 no.4
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• pp.386-396
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• 2002

This paper presents a neural network-based near-optimal routing algorithm. It employs a modified Hopfield Neural Network (MHNN) as a means to solve the shortest path problem. It uses every piece of information that is available at the peripheral neurons in addition to the highly correlated information that is available at the local neuron. Consequently, every neuron converges speedily and optimally to a stable state. The convergence is faster than what is usually found in algorithms that employ conventional Hopfield neural networks. Computer simulations support the indicated claims. The results are relatively independent of network topology for almost all source-destination pairs, which nay be useful for implementing the routing algorithms appropriate to multi -hop packet radio networks with time-varying network topology.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.185-197
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• 1993

The rostral ventrolateral medulla (RVLM) includes vasopressor neurons, which transmit activation signals to the intermediolateral nucleus (IML) of the spinal cord, where the preganglionic sympathetic nucleus is located, to raise arterial blood pressure (BP). However, controversy exists as to the possible depressor area in the RVLM and the pathway involved. The present study persued evidence far the location of depressor neurons and the pathway by simultaneously observing changes in BP and the firing rate (FR) of cardiovascular neurons (CVNs) in the RVLM during the somatosympathetic reflex (SSR) elicited by peripheral nerve stimulation, since CVNs are known to contribute to the generation of the sympathetic nerve discharge. In 42 cats, anaesthetized with $\alpha-chloralose$, single unit recording was performed, using carbon filament electrodes inserted into the RVLM, enabling estimation of the post R wave unit histogram (PR-UNlT) and the spike triggered average of sympathetic nerve discharge (STA-SND), allowing identification of CVNs. Antidromic stimulation of spinal $T_2$ segment was followed to determine whether the identified CVN projects axonal endings to the spinal cord (reticulospinal neuron). The sciatic nerve was electrically stimulated at $A\delta-intensity$ (1 mA, 0.1 ms), 1 Hz and C-intensity (10 mA, 0.5 ms), 20 Hz to elicit the depressor, and pressor responses of the SSR, respectively. Simultaneous measurement of CVN firing rate was made. Experimental results are summarized as follows. 1) 20 out of 98 CVNs had axonal projections to the spinal cord and 17 out of 98 CVNs showed FR changes during SSR. 2) Response patterns of FR and BP during SSR were classified into 8 types. 3) These 8 different response patterns could be further classified into those from pressor and depressor neurons. These results demonstrate that some CVNs were identifiable as reticulospinal neurons responding to anti-dromic stimulation and that CVNs operating as depressor neurons as well as pressor neurons exist in the RVLM, both of which are involved with SSR mediation. Therefore, evidence was found that an independent depressor pathway might be involved in the mediation of SSR.

• Journal of information and communication convergence engineering
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• v.10 no.2
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• pp.194-199
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• 2012

This paper proposes a novel scheme of a gray scale fingerprint image for a high-accuracy capacitive sensor chip. The conventional grayscale image scheme uses a digital-to-analog converter (DAC) of a large-scale layout or charge-pump circuit with high power consumption and complexity by a global clock signal. A modified capacitive detection circuit for the charge sharing scheme is proposed, which uses a down literal circuit (DLC) with a floating-gate metal-oxide semiconductor transistor (FGMOS) based on a neuron model. The detection circuit is designed and simulated in a 3.3 V, 0.35 ${\mu}m$ standard CMOS process. Because the proposed circuit does not need a comparator and peripheral circuits, the pixel layout size can be reduced and the image resolution can be improved.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.6
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• pp.566-573
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• 2004

This paper describes the ubiquitous home network (uHome-net) testbed and LonRF intelligent devices based on LonWorks technology. These devices consist of Neuron Chip, RF transceiver, sensor, and other peripheral components. Using LonRF devices, a home control network can be simplified and most devices can be operated on LonWorks control network. Also, Indoor Positioning System (IPS) that can serve various location based services was implemented in uHome-net. Smart Badge of IPS, that is a special LonRF device, can measure the 3D location of objects in the indoor environment. In the uHome-net testbed, remote control service, cooking help service, wireless remote metering service, baby monitoring service and security ＆ fire prevention service were realized. This research shows the vision of the ubiquitous home network that will be emerged in the near future.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.20-27
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• 2002

A role for ATP in nociception and pain induction was proposed. ATP-gated P2X ion channel receptors are localized throughout the nervous system and have been identified on neurons which participate in conduction of nociceptive information from the periphery to central nervous system. We consider the role of ATP as a peripheral activator of nociceptive sensory neuron via ATP-gated ion channels.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1422-1427
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• 1992

Askin tumor is rare malignant small round cell tumor that orgins from interconstal nerve of chest in children It was not until 1979 that Askin first reported that tumor. Although few sporadic reports had been reported, its incidence were too low to analize its clinical featurs. That tumors prognosis is so grave that no therapy would success to cure, but early diagnosis and enbloc excision with following combind chemotherapy and radiotherapy will prolong their survival. Other small round cell tumors of chest wall that must differentiate are Ewing`s sarcoma, rhabdomyosarcoma, lymphoma, neuroblastoma and pulmonary bla-stoma. The most prominant histologic charactersistics of this tumor is neuron specific eno-lase which is detected with immunohistochemistry technique, and neurosecretary electron dense granules within cytoplasm. We expirienced a case of Askin tumor occuring 12-year-old female who has huge right lower chest mass with dull chest pain. She have been underwent excision and postoperative radiotherapy. We are following her up for months and there is no evidence of local recurrence.