• 제목/요약/키워드: Tail latency

검색결과 55건 처리시간 0.019초

청반핵 자극으로 인한 노르아드레날린의 유리가 동통의 조절에 미치는 영향 (Effects of Locus Coeruleus/Subcoeruleus Stimulation on the Tail Flick Reflex and Efflux of Noradrenaline into the Spinal Cord Superfusates)

  • 박경표;김종성;서대철;박형섭
    • 대한약리학회지
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    • 제30권1호
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    • pp.29-37
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    • 1994
  • 배외측 뇌교의 전기자극은 척수 수준에서 동통의 역치를 증가시키고, 또한 말초로 부터 오는 유해성 자극에 의해 야기되는 척수후각세포의 흥분성을 억제하여 진통효과를 나타낸다. 이러한 진통효과는 noradrdnergic 원심신경을 매개로 한다고 하였지만, 이직까지 이를 직접적으로 뒷받침하는 신경화학적인 증거는 보고되지 않았다. 따라서 본 실험은 뇌교에 위치한 청반핵(Locus coeruleus)의 전기자극시, 척수 수준에서 일어나는 동통조절효과를 쥐꼬리 회피 반사(Tail Flick Reflex)를 이용해 관찰하고, 이러한 동통조절효과는 어떤 신경전달물질을 매개로해서 일어나며, 또한 생체내에서 직접 유리 되는지 살펴보기 위해 Push Pull technique을 이용해 척수액내 noradrenaline의 농도 변화를 HPLC로 측정하였다. 청반핵자극시의 동통조절기전을 알아보기위해 yohimbine, naloxone 그리고 vehicle의 3group 으로 나누어 각 길항제의 효과를 실험하였다. 청반핵 자극시 TF latency의 증가(>6.Ssec)를 보이는 역치 자극강도가 yohimbine $30{\mu}g$을 척수내로 투여한 후에는 $135\;{\mu}A$로서 안정시의 $55\;{\mu}A$에 비해 147% 증가되어 유의한 변화를 보여주었다(P<0.01, n=5). $Naloxone\;20{/mu}g$을 투여한 실험군 에서도 초기 역치자극강도 $54\;{\mu}A$에서 $120\;{\mu}A$로서 123% 증가되어 역시 유의한 변화를 보여주었다(P<0.01, n=5). 그러나 vehicle group에서는 투여 전, 후 역치자극강도의 변화가 없었다. 청반핵 자극이 없는 안정상태에서의 TF latency 값은 모두 3.1 sec였고 yohimbine과 naloxone투여후에는 각각 2.5 sec,2.6sec로 감소되어, 긴장성 억제가 차단되는 것으로 나타났다(각각 P<0.05,P<0.1,n=5).청반핵의 전기자극$(100\;{\mu}A)$은 척수액내 noradrenaline의 농도를 증가시켰으나(평균 4.18mg/ml에서 7.74 ng/ml로, p<0.05, n=10),dopamine의 농도는 증가되지 않았다. 이상의 결과는 청반핵 자극에 의한 척수내 동통조절효과는 opioid 계외에 부분적으로 noradrdnaline을 매개로 해서 이루어지며, 이에 관여하는 수용체는 ${\alpha}_2$ 임을 보여주었다.

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Optimizing Garbage Collection Overhead of Host-level Flash Translation Layer for Journaling Filesystems

  • Son, Sehee;Ahn, Sungyong
    • International Journal of Internet, Broadcasting and Communication
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    • 제13권2호
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    • pp.27-35
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    • 2021
  • NAND flash memory-based SSD needs an internal software, Flash Translation Layer(FTL) to provide traditional block device interface to the host because of its physical constraints, such as erase-before-write and large erase block. However, because useful host-side information cannot be delivered to FTL through the narrow block device interface, SSDs suffer from a variety of problems such as increasing garbage collection overhead, large tail-latency, and unpredictable I/O latency. Otherwise, the new type of SSD, open-channel SSD exposes the internal structure of SSD to the host so that underlying NAND flash memory can be managed directly by the host-level FTL. Especially, I/O data classification by using host-side information can achieve the reduction of garbage collection overhead. In this paper, we propose a new scheme to reduce garbage collection overhead of open-channel SSD by separating the journal from other file data for the journaling filesystem. Because journal has different lifespan with other file data, the Write Amplification Factor (WAF) caused by garbage collection can be reduced. The proposed scheme is implemented by modifying the host-level FTL of Linux and evaluated with both Fio and Filebench. According to the experiment results, the proposed scheme improves I/O performance by 46%~50% while reducing the WAF of open-channel SSDs by more than 33% compared to the previous one.

부자(附子)의 우울증 억제효과에 관한 연구 (Anti-depressant Effect of the Extracts of Aconitum carmichaeli)

  • 장문규;김근우;구병수
    • 동의신경정신과학회지
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    • 제20권3호
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    • pp.49-64
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    • 2009
  • Objectives : The water and methanol extracts of Aconitum carmichaeli(Aconiti Tuber Preparat) were investigated for their anti-depressant effects. Methods : In this study, reserpine-induced hypothermia test, tail suspension test and hot plate test. Additionally, the brain monoamine oxidase activity was determined in vivo. Results: In the reserpine-induced hypothermia test, both extracts suppressed the fall of body temperature compared to the control group in a dose-dependent manner, suggesting the inhibition on hypothermia. In the tail suspension test, the methanol extract dose-dependently reduced the duration of immobility by 28.4% at a dose of 1 g/kg compared to control group, which is more effective than the water extract. In the hot plate test, the water extract and methanol extract increased the jump latency time compared to the control group, showing the inhibition rate of 198% and 182%, respectively, at a dose of 1 g/kg. Methanol extracts potently inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, showing 84.6% inhibition, but the water extract revealed very weak activity. Conclusions : Above results suggested that the extract of Aconitum carmichaeli can be useful for the prevention and treatment of depression.

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초음파경혈요법의 진통소염효과 연구 (Analgesic and Anti-inflammatory Effects of Sono-acupoint Therapy)

  • 임사비나;손양선;진수희
    • Journal of Acupuncture Research
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    • 제19권5호
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    • pp.176-188
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    • 2002
  • Objective : Sono-acupoint (SA) therapy is a new therapeutic technique that combined with acupuncture points, herbal medicine and ultrasound therapy. This study was carried out to investigate the analgesic and anti-inflammatory effects of sono-acupoint therapy. Methods : We performed the tail-flick test with normal rats to examine the tail-flick latency (TFL), and the Freund's adjuvant-induced arthritis rat model to examine the edema, skin temperature and serum concentration of c-reactive protein and rheumatoid factor (RF). Herbal SA (HSA) treatment was performed at bilateral Zusanli (ST36) with the hanbang-gel made of several selected herbal drugs in Sprague-Dawley rats (male, $250{\pm}30g$). General SA (GSA) treatment was performed at bilateral Zusanli (ST36) with the gel used in ultrasound therapy. In arthritis rat model, Freund's adjuvant (50mg/ml) was injected in dorsal part of right foot, and these treatments were performed after 15 days. Results : TFL was lengthened after SA treatments. Skin temperature and RF concentration that were the evidence of arthritis in rats were decreased by HSA treatment (P < 0.05). Conclusion : These results indicate that HSA has the analgesic and anti-inflammatory effects in rats, and further developments will produce the advance of this new therapeutic skill.

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The Analgesic Effect of Bee Venom Acupuncture and Its Mechanism on the Type II Collagen-Induced Arthritis Rats

  • Seo, Byung-Kwan;Baek, Yong-Hyun;Choi, Do-Young;Park, Dong-Suk
    • Journal of Acupuncture Research
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    • 제22권2호
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    • pp.19-32
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    • 2005
  • Objectives : to evaluate the analgesic effect of bee venom acupuncture on Choksamni (ST36) in the collagen-induced arthritis rats and investigate the role played by serotonergic receptor subtypes (5-HT1a, 5-HT2a) in the antinociceptive effect of bee venom acupuncture in a thermal hyperalgesia test Methods : Experiments were performed on 5 week-aged 60 male Sprague-Dawley rats according to National Institute of Health guidelines and the ethical guidelines of the International Association for the Study of Pain (IASP). Arthritis was induced with arthrogenic collagen emulsion (Bovine type II collagen ${\mu}g$ with incomplete Freund's adjuvant $100\;{\mu}g$). The onset of arthritis was considered to be present when erythema and swelling were detected in at least one joint. The thermal hyperalgesia was evaluated weekly with tail flick test in the rats of severity grade 3 without any injury at tail and foot (including inflammation, ulceration, snap). In the fourth week after first immunization, the analgesic effect of bee venom acupuncture (Choksamni, ST36) was measured with consecutive tail flick latency after intraperitoneal injection of spiroxatrine (1mg/kg) and spiperone (1mg/kg). Results : Chronic inflammatory pain was induced as time elapsed after the immunization of arthrogenic collagen and the maximum value was reached from third to fifth week. Chronic inflammatory pain induced by CIA was inhibited by bee venom acupuncture on the left ST36. The analgesic effect of bee venom acupuncture was inhibited by intraperitoneal injection of 5-HT1a antagonist spiroxatrine and 5-HT2a antagonist spiperone. Conclusions : Therefore, a conclusion. that the analgesic effect of bee venom acupuncture in the chronic inflammatory pain is partially mediated by 5-HT1a and 5-HT2a receptors can be made.

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곤달비 메탄올 추출물의 진통 효과 (Anti-nociceptive Activity of Methanol Extracts from Ligularia stenocephala)

  • 차동석;전훈
    • 생약학회지
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    • 제44권1호
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    • pp.70-74
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    • 2013
  • Ligularia stenocephala has been widely used as a traditional medicine for the treatment of lots of diseases such as asthma, arthritis, and jaundice. In this study, we evaluated the anti-nocicepitve activities of methanolic extract of L. stenocephala (MLS) using various pain models including thermal nociception as well as chemical nociception methods. MLS showed significant increase in latency time in the tail immersion test and hot-plate test. In addition, the number of acetic acid-induced abdominal constrictions was decreased by MLS. MLS also attenuated paw licking time in the formalin test. The combination test using naloxone revealed that the anti-nociceptive properties of MLS was not associated with opioid receptor activation. The present results demonstrate that MLS may possibly used as valuable analgesic agent for the treatment of nociceptive pain.

Loxoprofen sodium 플라스타의 소염, 진통 작용 및 혈중 약물 농도에 대한 연구 (Anti-inflammatory and Analgesic Activities, and Plasma Concentration of Loxoprofen Sodium Plasters)

  • 채주병;전홍렬;이승목;정남주;김수균;조길도;김동연
    • Biomolecules & Therapeutics
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    • 제7권2호
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    • pp.198-203
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    • 1999
  • Loxoprofen-Na (sodium 2-〔4-(2-oxocyclopentylmethyl)pheny)propionate dihydrate) is a potent analgesic drug. We developed loxoprofen-Na plasters to extend duration time of analgesic activity and to reduce side effect on gastrointestinal tract. Analgesic effect of Loxoprofen-Na plasters was investigated. Loxoprofen-Na plaster had good analgesic effect in rat paw pressure test, Tail-flick latency test and acetic acid-induced writhing test. Also, it had anti-inflammatory effect on carrageenan-induced rat hind paw edema. In pharmacokinetic study of Loxoprofen-Na, plasters dosage form showed that plasma drug concentration was prolonged up to 14 hours. So, we can conclude that loxoprofen-Na plasters, when applied on skin, will be a new type of drug for controlling the various local pain or inflammation.

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Carrageenan으로 유도된 염증성 근통증 흰쥐 모델에서 경피신경전기자극과 냉치료에 의한 비복근의 cyclooxygenase-2의 감소 (Reduction of muscle cyclooxygenase-2 with transcutaneous electrical nerve stimulation and cold therapy in rats of carrageenan-induced inflammatory muscle pain)

  • 백윤웅;채윤원
    • 대한물리치료과학회지
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    • 제9권1호
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    • pp.89-94
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    • 2002
  • Prostaglandins are generated through two isoforms of the enzyme cyclooxygenase, constitutively expressed cyclooxygenase(COX)-1 and COX-2, which is induced at sites of inflammation. Inhibition of COX-2 is desirable as this may avoid side effects seen with NSAIDs. We examined the effects of transcutaneous electrical nerve stimulation and cold therapy on the levels of muscle cycloooxygenase-2 mRNA in rats of carrageenan-induced inflammatory. The method of behavioral assessment were paw withdrawal latency(PWL) and tail flick test(TFT). The COX-2 mRNA levels were quantified by reverse transcription-polymerase chain reaction (RT-PCR). Following the transcutaneous electrical nerve stimulation and cold therapy, PWL and TFT were increased and COX-2 mRNA expression in gastrocnemius muscles were decreased. These results suggest that a transcutaneous electrical nerve stimulation and cold therapy were good therapy for a muscle pain.

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신경병증성 통증에 대한 자동염전침의 진통효과 및 opioid 기전 (The Effects of Automatically Controlled Rotating Acupuncture on Thermal Allodynia in a Rat Model of Neuropathic Pain: Mediation by Endogenous Opioid System)

  • 박정혁;김선광;나효석;문학진;민병일;김기홍;임성수;이순걸;이상훈
    • Journal of Acupuncture Research
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    • 제23권5호
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    • pp.23-29
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    • 2006
  • Objectives : The present study was conducted to evaluate the effects of automatically controlled rotating acupuncture (ACRA) on thermal allodynia in neuropathic pain rats, and to examine whether the endogenous opioid system mediates the effects of ACRA. Methods : For the neuropathic surgery, the right superior caudal trunk was resected at the level between S1 and S2 spinal nerves innervating the tail. Two weeks after the nerve injury, ACRA stimulation with 4 different stimulation conditions (i.e., angle and frequency of rotation: 90o+1Hz, 90o+1/4Hz, 360o+/1Hz, and 360o+1/4Hz) was delivered to the Zusanli (ST36) acupoint for 15 min. The behavioral signs of thermal allodynia were evaluated by the tail immersion test (i.e., immersing the tail in cold $(4^{\circ}C)$ or warm $(4^{\circ}C)$ water and measuring the latency to an abrupt tail movement) before and after the stimulation. In an additional set of experiments, we examined the effects of naloxone (opioid Results : ACRA stimulations under all of the conditions above significantly relieved thermal antagonist, 2mg/kg, i.p.) on the action of ACRA stimulation. allodynia. There is no difference in the anti-allodynic effects among the 4 stimulation conditions. In addition, the effect of ACRA on thermal allodynia was reversed by naloxone pretreatment. Conclusion : These results indicate that ACRA stimulations have relieving effects on thermal allodynia in neuropathic pain rats, irrespective of stimulation parameters, and that this is mediated by the endogenous opioid system.

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Medetomidine의 투여가 흰쥐의 진통과 진정효과에 미치는 영향 (Effects of Medetomidine on Analgesia and Sedation in Rats)

  • 장환수;이만기
    • 한국임상수의학회지
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    • 제27권6호
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    • pp.674-678
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    • 2010
  • Medetomdine의 투여가 흰쥐의 진통과 진정효과에 미치는 영향에 대하여 평가하였다. 실험동물은 생리식염수 1 ml/kg 투여군 (group 'Saline'), butorphanol, 2.0 mg/kg 투여군 (group 'BUT'), medetomidine, 0.2, 0.4, 0.8 or 1.6 mg/kg 투여군 (각각 group 'MED0.2', 'MED0.4', 'MED0.8' and 'MED1.6') 등 6개의 실험군으로 나누어졌다. 진통효과는 $50^{\circ}C$ hot-water tail-flick latency test로 측정하였고, 진정효과는 numerical sedation score (NSS)와 정위반사 (righting reflex)로 평가하였다. MED0.2군을 제외한 모든 medetomidine 투여군들이 Saline군에 비해 유의적인 진통효과의 증가를 보였다. MED0.2군과 비교할 때 MED0.4와 MED0.8군은 유의적인 진통효과의 상승을 보였으나, MED1.6군은 유의적인 변화를 보이지 않았다. BUT군과 모든 medetomidine 투여군은 진통효과에서 유의적인 차이를 보이지 않았다. Saline과 butorphanol의 투여는 진정효과와 정위반사의 소실을 유발하지 않았다. Medetomidine의 투여 용량의 증가는 진정효과를 증가시켰다. MED0.2군과 비교할 때 MED0.4, MED0.8과 MED1.6군의 NSS가 유의적으로 증가하였으나, MED0.4군에 비해서는 MED0.8과 MED1.6군이 유의적인 차이를 나타내지 않았다. 정위반사의 소실 시간은 MED0.2군에 비해 MED0.8과 MED1.6군이 유의적으로 감소하였다. 본 실험의 결과로 볼 때, 흰쥐에서 medetomidine 0.4에서 0.8 mg/kg 이내의 용량을 복강내 투여할 때 신뢰할 수 있는 진통효과와 진정효과를 동시에 얻을 수 있으며, 따라서 흰쥐의 진정, 진통 및 화학적 보정 목적에 적절한 용량임을 알 수 있었다.