• 한국식품저장유통학회지
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• 제31권2호
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• pp.298-306
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• 2024

본 연구에서는 식물 추출물 혼합 분말의 근육세포 분화 및 산화적 스트레스에 대한 세포 보호 효과를 확인하고자 하였다. 추출물을 최대 1,000 ㎍/mL 농도까지 세포에 처리한 결과, 세포 생존율이 감소하지 않음을 확인되었다. 식물 추출물 혼합분말이 근육세포 분화 인자에 미치는 영향을 확인하기 위해 myogenin과 MHC의 발현 여부를 확인한 결과, 무처리군에 비해 발현이 증가함을 확인하였다. H₂O₂에 의해 유도된 산화적 스트레스에 대한 세포 보호 효과를 확인한 결과, 식물 추출물 혼합 분말 처리에 의해 H₂O₂ 단독 처리군보다 세포 생존율이 증가하였으며, LDH와 creatine kinase의 활성이 감소하였다. 또한, Bax와 Bcl-2의 발현을 조절하여 caspase-9와 -3 활성화를 억제함을 확인하였다. 이를 통해 식물 추출물 혼합 분말의 근육세포 분화 효과 및 H₂O₂에 의해 유도된 산화적 스트레스에 대한 세포 보호 효과가 있음을 확인하였다. 따라서 식물 추출물 혼합 분말은 근감소증 개선을 위한 기능성 소재로써 활용이 가능할 것으로 판단되며, 향후 근감소증 개선을 위한 기능성 소재로서의 유효성 확보를 위해서 근감소증 세포 및 동물모델을 이용한 효능 및 기전 분석 연구가 더 필요할 것으로 사료된다.

• International Journal of Oral Biology
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• 제36권2호
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• pp.71-78
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• 2011

Using whole cell current- and voltage-clamp recording we investigated the characteristics and pharmacology of group I metabotropic glutamate receptor (mGluR)-mediated responses in rat medial vestibular nucleus (MVN) neurons. In current clamp conditions, activation of mGluR I by application of the group I mGluR agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) induced a direct excitation of MVN neurons that is characterized by depolarization and increased spontaneous firing frequency. To identify which of mGluR subtypes are responsible for the various actions of DHPG in MVN, we used two subtype-selective antagonists. (S)-(+)- alpha-amino-a-methylbenzeneacetic acid (LY367385) is a potent competitive antagonist that is selective for mGluR1, whereas 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is a potent noncompetitive antagonist that is selective for mGluR5. In voltage clamp conditions, DHPG application increased the frequency of spontaneous and miniature inhibitory postsynaptic currents (IPSCs) but had no effect on amplitude distributions. Antagonism of the DHPG-induced increase of miniature IPSCs required the blockade of both mGluR1 and mGluR5. DHPG application induced an inward current, which can be enhanced under depolarized conditions. DHPG-induced current was blocked by LY367385, but not by MPEP. Both LY367385 and MPEP antagonized the DHPG-induced suppression of the calcium activated potassium current ($I_{AHP}$). These data suggest that mGluR1 and mGluR5 have similar roles in the regulation of the excitability of MVN neurons, and show a little distinct. Furthermore, mGluR I, via pre- and postsynaptic actions, have the potential to modulate the functions of the MVN.

• International Journal of Oral Biology
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• 제34권4호
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• pp.215-222
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• 2009

Medial vestibular nucleus (MVN) neurons are involved in the reflex control of the head and eyes, and in the recovery of vestibular function after the formation of peripheral vestibular lesions. In our present study, whole cell patch clamp recordings were carried out on MVN neurons in brainstem slices from neonatal rats to investigate the actions of a group I metabotropic glutamate receptor (mGluR) agonist upon synaptic transmission and ionic currents. Application of the mGluR I agonist (S)-3,5- dihydroxyphenylglycine (DHPG) increased the frequency of miniature inhibitory postsynaptic currents (mIPSCs) but had no effect upon amplitude distributions. To then identify which of mGluR subtypes is responsible for the actions of DHPG in the MVN, we employed two novel subtype selective antagonists. (S)-(+)-$\alpha$-amino-a-methylbenzeneacetic acid (LY367385) is a potent competitive antagonist that is selective for mGluR1, whereas 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is a potent noncompetitive antagonist of mGluR5. Both LY367385 and MPEP antagonized the DHPG-induced increase of mIPSCs, with the former being more potent. DHPG was also found to induce an inward current, which can be enhanced under depolarized conditions. This DHPG-induced current was reduced by both LY367385 and MPEP. The DHPG-induced inward current was also suppressed by the PLC blocker U-73122, the $IP_3$ receptor antagonist 2-APB, and following the depletion of the intracellular $Ca^{2+}$ pool by thapsigargin. These data suggest that the DHPG-induced inward current may be mainly regulated by the intracellular $Ca^{2+}$ store via the PLC-$IP_3$ pathway. In conclusion, mGluR I, via pre- and postsynaptic actions, may modulate the excitability of the MVN neurons.

• 디지털융복합연구
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• 제12권12호
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• pp.491-506
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• 2014

본 연구의 목적은 방송광고에 장르 개념을 학제적으로 적용하여 방송광고에서의 장르 역할에 대한 기대관점과 장르 활용에 대한 태도가 소구유형으로서의 방송광고 장르 호감도에 미치는 영향을 탐색적으로 살펴보는데 있다. 연구 결과, 거시환경적 기대관점과 부정적 태도 간에, 미시실용적 기대관점과 긍정적 태도 간에 높은 상관관계가 있는 것으로 나타났다. 통합상황적 기대관점의 소비자는 방송광고에서의 장르 역할에 이중적 태도를 갖고 있는 것으로 조사되었다. 방송광고에서 장르의 역할에 미시실용적 기대관점을 지닌 소비자는 비교광고와 성표현광고 호감도가 상대적으로 더 높게 나타났고, 통합상황적 기대관점을 가진 소비자는 거시환경적 기대관점과 미시실용적 기대관점의 중간적인 호감도를 보였다. 방송광고에서의 장르 활용에 긍정적 태도를 갖고 있는 경우 비교광고와 성표현광고 호감도가 상대적으로 더 높은 것으로 나타났고, 이중적 태도를 가진 소비자의 방송광고 장르 유형에 대한 호감도는 부정적 태도와 긍정적 태도의 중간적인 것으로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.278-280
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• 2007

In this paper, wd design the Program Specific Information (PSI) parser and its On-Screen Display (OSD) on the middleware of ALi M3330 MPEG-2 decoder processor to analyze DVB-T Transport Stream(TS) information. To test the functional operation of the designed parser, we implement the DVB-T test board including the RF-tuner using ALi M3330 MPEP-2 decoder processor and confirm the correct operation using the input TS stream generated by DVB-T stream generator. The developed PSI parser could be used for the test environment, various channel extension, and the development of DVB-T reception module.

• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.531-540
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• 2022

Group 1 metabotropic glutamate receptors (mGluRs) can positively affect postsynaptic neuronal excitability and epileptogenesis. The objective of the present study was to determine whether group 1 mGluRs might be involved in synaptically-induced intracellular free Ca²⁺ concentration ([Ca²⁺]_i) spikes and neuronal cell death induced by 0.1 mM Mg²⁺ and 10 µM glycine in cultured rat hippocampal neurons from embryonic day 17 fetal Sprague-Dawley rats using imaging methods for Ca²⁺ and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays for cell survival. Reduction of extracellular Mg²⁺ concentration ([Mg²⁺]_o) to 0.1 mM induced repetitive [Ca²⁺]_i spikes within 30 sec at day 11.5. The mGluR5 antagonist 6-Methyl2-(phenylethynyl) pyridine (MPEP) almost completely inhibited the [Ca²⁺]_i spikes, but the mGluR1 antagonist LY367385 did not. The group 1 mGluRs agonist, 3,5-dihydroxyphenylglycine (DHPG), significantly increased the [Ca²⁺]_i spikes. The phospholipase C inhibitor U73122 significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The IP₃ receptor antagonist 2-aminoethoxydiphenyl borate or the ryanodine receptor antagonist 8-(diethylamino)octyl 3,4,5-trimethoxybenzoate also significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The TRPC channel inhibitors SKF96365 and flufenamic acid significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The mGluR5 antagonist MPEP significantly increased the neuronal cell survival, but mGluR1 antagonist LY367385 did not. These results suggest a possibility that mGluR5 is involved in synaptically-induced [Ca²⁺]_i spikes and neuronal cell death in cultured rat hippocampal neurons by releasing Ca²⁺ from IP₃ and ryanodine-sensitive intracellular stores and activating TRPC channels.

• The Korean Journal of Physiology and Pharmacology
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• 제12권5호
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• pp.237-243
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• 2008

Intraplantar injection of melittin has been known to induce sustained decrease of mechanical threshold and increase of spontaneous flinchings. The present study was undertaken to investigate how the melittin-induced nociceptive responses were modulated by changes of metabotropic glutamate receptor (mGluR) activity. Changes in paw withdrawal threshold (PWT), number of flinchings and paw thickness were measured at a given time point after injection of melittin ($10{\mu}g$/paw) into the mid-plantar area of rat hindpaw. To observe the effects of mGluRs on the melittin-induced nociceptions, group I mGluR (AIDA, $100{\mu}g$ and $200{\mu}g$), $mGluR_1$ (LY367385, $50{\mu}g$ and $100{\mu}g$) and $mGluR_5$ (MPEP, $200{\mu}g$ and $300{\mu}g$) antagonists, group II (APDC, $100{\mu}g$ and $200{\mu}g$) and III (L-SOP, $100{\mu}g$ and $200{\mu}g$) agonists were intrathecally administered 20 min before melittin injection. Intraplantar injection of melittin induced a sustained decrease of mechanical threshold, spontaneous flinchings and edema. The effects of melittin to reduce mechanical threshold and to induce spontaneous flinchings were significantly suppressed following intrathecal pre-administration of group I mGluR, $mGluR_1$ and $mGluR_5$ antagonists, group II and III mGluR agonists. Group I mGluR antagonists and group II and III mGluR agonists had no significant effect on melittin-induced edema. These experimental findings indicate that multiple spinal mGluRs are involved in the modulation of melittin-induced nociceptive responses.