• Journal of Oral Medicine and Pain
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• v.41 no.4
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• pp.195-199
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• 2016

Central sensitization represents a functional change of second order neuron induced by continuous deep pain input and maintained by psychosocial factors. When afferent neurons are involved with central sensitization, secondary hyperalgesia can appear. Secondary hyperalgesia is an increased sensitivity to stimulation without a local cause. Reports on secondary hyperalgesia to heat stimuli are relatively rare compared to mechanical stimuli. And there were few reports of secondary hyperalgesia to heat stimuli in the oral cavity. We presented a case of secondary hyperalgesia to heat stimuli in the gingival area induced by continuous odontogenic pain with a review of the related literature.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.102-102
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• 2003

• 한국약용작물학회:학술대회논문집
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• 2006.04a
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• pp.75-90
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• 2006

Both synthetic and endogenous $A{\beta}$ are degraded by peptidase G. Both $A{\beta}40$ and 42 are cleaved by peptidase G. Peptidase G cleaves $A{\beta}40$ into small fragments ($A{\beta}18$) which lacks aggregation property and are not toxic to neuron. Peptidase G seems to degrade multimeric $A{\beta}$ more efficiently than monomeric $A{\beta}$. Peptidase G protects neurons from toxicity induced by $A{\beta}$ by cleaving it into smaller fragments. Thus, dis-regulation of peptidase G could contribute amyloid deposit found in AD brain.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.304.2-304.2
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• 2002

In central nervous system. matrix metalloproteinases (MMPs) are produced by neuron as well as glia and implicated in physiological events such as neurite outgrowth and myelination etc. In addition. MMPs also contribute to the pathogenesis of several CNS diseases such as multiple sclerosis, Alzheimer's disease and malignant glioma. In spite of their functional importance, little is known about the signal transduction pathways leading to the induction of MMPs in CNS. Here. we investigated whether the activation of Erk(1/2) is involved in the induction of MMP-9 in LPS-stimulated primary astrocytes. (omitted)

• International Journal of Stem Cells
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• v.16 no.1
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• pp.117-122
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• 2023

Background and Objectives: mRNA-based protein expression technology has been used to express functional proteins. We have previously generated dopamine neurons from rat-embryo derived neural precursor cells (NPCs) through repeated transfection of synthetic transcription factor mRNA encoding dopamine-inducible genes. However, NPCs began to die approximately 10 d post-transfection. In this study, we examined a long-term transfection protocol that did not affect cell viability. Methods and Results: Experiments were performed in eight groups sorted according to the start date of mRNA transfection. mRNA was transfected into NPCs daily for 21 d and live cell images of each group were recorded. NPCs which were differentiated for more than five days showed sustained gene expression and appreciable viability despite daily mRNA transfection for 21 d. Conclusions: Repeated mRNA transfection requires cells with a sufficient differentiation period.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.401-412
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• 2013

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.102-102
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• 2003

Embryonic stem (ES) cells proliferate extensively in the undifferentiated state and have the potential to differentiate into a variety of cell types in response to various environmental cues. The generation of functional dopaminergic neurons from ES cells is promising for cell replacement therapy to treat Parkinson's disease. We compared the in vitro differentiation potential of pluripotent human embryonic stem (hES, MB03) cells induced with basic fibroblast growth factor (bFGF) or retinoic acid (RA). Both types of treatment resulted in similar neural cell differentiation patterns at the terminal differentiation stage, specifically, 75% neurons and 11% glial cells. Additionally, treatment of hES cells with brain derived neurotrophic factor (BDNF) or transforming growth factor (TGF)- $\alpha$ during the terminal differentiation stage led to significantly increased tyrosine hydroxylase (TH) expression, compared to control (P<0.05). In contrast, no effect was observed on the rate of mature or glutamic acid decarboxylase-positive neurons. Immunostaining and HPLC analyses revealed the higher levels of TH (20.3%) and dopamine in bFGF and TGF-$\alpha$ treated hES cells than in RA or BDNF treated hES cells. The results indicate that TGF-$\alpha$ may be successfully used in the bFGF induction protocol to yield higher numbers of functional dopaminergic neurons from hES cells.

• Proceedings of the KOSOMBE Conference
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• v.1991 no.05
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• pp.34-38
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• 1991

This paper describes and discusses the employment of EMG pattern analysis to provide upper-motor-neuron paraplegics with patient-responsive control of FES (functional electrical stimulation) for the purpose of walker-supported walking. The use of above - lesion EMG signals as a solution to the control problem is considered. The AR (autoregressive) parameters are identified by Kalman filter algorithm using DSP chip and classified by fuzzy theory. The control and stimuli part of the below-lesion are based on microprocessor(8031). The designed stimulator is a 4-channel version. The experiments described above have only attempted to discriminate between standing function and sit-down function. A further advantage of the this system is applied for motor rehabilitation of social readaption of paralyzed humans.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.73-73
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• 2003

Purpose: To determine the motor cortex dysfunction in hemiparetic patients due to deep intracerebral hematoma, authors performed proton magnetic resonance spectroscopy (lH MRS) for the evaluation of biochemical changes in the cortex on affected hemisphere according to axonal injury at the level of internal capsule. Methods: Ten control subjects and 14 patients with documentable hemiparesis of varying severity hemiparesis were included. All the hemiparesis was caused by deep intracerebral hematoma (putaminal and thalamic hemorrhage). In vivo 1H MRS study was performed on a 3T MRI/MRS system using STEAM sequence. As a single-voxel technique, Spectral parameters were: 20 ms TE, 2000 ms TR, 128 averages, 2500 Hz spectral width, and 2048 data points. Results: We found that the mean N-acetylaspartate (NAA)/phosphocreatine (Cr) and NAA/choline (Cho) ratios were significantly decreased in the motor cortex of the hemiparesis patients compared with control subjects. Conclusions: 1H MRS examinations of the motor cortex might help to differentiate distinct clinical entities of hemiparesis and to monitor pharmacological effects in therapeutic trials, providing a quantitative biological marker for motor neuron dysfunction. Acknowledgement: This study was supported by a grant of the Center for Functional and Metabolic Imaging Technology, Ministry of Health & Welfare, Republic of Korea. (02-PJ3-PG6-EV07-000).

• Applied Microscopy
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• v.48 no.1
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• pp.11-16
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• 2018

For Odontamblyopus lacepedii with small and turbid eyes, the gross structure and histology of the olfactory organ, which is important for its survival and protection of the receptor neuron in estuarial environment and its ecological habit, was investigated using a stereo, light and scanning electron microscopes. Externally, the paired olfactory organs with two nostrils are located identically on each side of the snout. These nostrils are positioned at the anterior tip of the upper lip (anterior nostril) and just below eyes covered with the epidermis (posterior nostril). Internally, this is built of an elongated olfactory chamber and two accessory nasal sacs. In histology, the olfactory chamber is elliptical in shape, and lined by the sensory epithelium and the non-sensory epithelium. The sensory epithelium of a pseudostratified layer consists of olfactory receptor neurons, supporting cells, basal cells and lymphatic cells. The non-sensory epithelium of a stratified layer has swollen stratified epithelial cells and mucous cells with acidic and neutral sulfomucin. From these results, we confirmed the olfactory organ of O. lacepedii is adapted to its ecological habit as well as its habitat with burrows at the muddy field with standing and murky waters.