• Title/Summary/Keyword: Tail latency

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

  • Park, Kyung-Pyo;Kim, Jong-Sung;Suh, Dae-Chul;Park, Hyoung-Sup
    • The Korean Journal of Pharmacology
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    • v.30 no.1
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    • pp.29-37
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    • 1994
  • Inhibition of the nociceptive Tail Flick Reflex (TFR) was observed with electrical stimulation of the locus coeruleus/subcoeruleus (LC/SC) in the male Sprague - Dawley rats under light anesthesia, and the involved neurotransmitter (s) were characterized. Electrical stimulation of LC/SC induced the analgesia with the stimulation threshold (intensity of the current, given for 100 usec and in 100 Hz frequency, which caused the TF latency longer than 6.5 sec) around 55 uA. Intrathecal administrations of ${\alpha}_2$ antagonist, yohimbine (30 ug) or opioid antagonist, naloxone (20 ug) increased the stimulation threshold by 147% and 123% respectively (from 55 uA to 135 uA,9 and from 54 uA to 123 uA;P0.01, n=5, each). The basal TF latency without stimulation (3.1 sec) was reduced by the antagonists (to 2.5 sec by yohimbine, p<0.05, n=5; to 2.6 sec by naloxone, p<0.1, n=5), vehicle only did not show any effect. Noradrenaline(NA) in the spinal cord superfusates measured with HPLC was increased by the LC/SC stimulation, from 4.18 ng/ml before to 7.74 ng/ml after stimulation (P<0.05, n=10). The result suggest that analgesia induced by LC/SC stimulation is mediated, at least in part, by the noradrenergic system in which ${\alpha}_2$ receptor is involved, as well as the opioid system.

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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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    • v.13 no.2
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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.

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

  • Chang, Moon-Kyoo;Kim, Geun-Woo;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.20 no.3
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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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Analgesic and Anti-inflammatory Effects of Sono-acupoint Therapy (초음파경혈요법의 진통소염효과 연구)

  • Lim, Sabina;Son, Yang-sun;Jin, Soo-hee
    • Journal of Acupuncture Research
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    • v.19 no.5
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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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    • v.22 no.2
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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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Anti-nociceptive Activity of Methanol Extracts from Ligularia stenocephala (곤달비 메탄올 추출물의 진통 효과)

  • Cha, Dong Seok;Jeon, Hoon
    • Korean Journal of Pharmacognosy
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    • v.44 no.1
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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.

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

  • 채주병;전홍렬;이승목;정남주;김수균;조길도;김동연
    • Biomolecules & Therapeutics
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    • v.7 no.2
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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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Reduction of muscle cyclooxygenase-2 with transcutaneous electrical nerve stimulation and cold therapy in rats of carrageenan-induced inflammatory muscle pain (Carrageenan으로 유도된 염증성 근통증 흰쥐 모델에서 경피신경전기자극과 냉치료에 의한 비복근의 cyclooxygenase-2의 감소)

  • Paek, Yun-Woong;Chae, Yun-Won
    • Journal of Korean Physical Therapy Science
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    • v.9 no.1
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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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The Effects of Automatically Controlled Rotating Acupuncture on Thermal Allodynia in a Rat Model of Neuropathic Pain: Mediation by Endogenous Opioid System (신경병증성 통증에 대한 자동염전침의 진통효과 및 opioid 기전)

  • Park, Jung-Hyuk;Kim, Sun-Kwang;Na, Hyo-Suk;Moon, Hak-Jin;Min, Byung-Il;Kim, Ki-Hong;Rhim, Sung-Soo;Lee, Soon-Geul;Lee, Sang-Hoon
    • Journal of Acupuncture Research
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    • v.23 no.5
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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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Effects of Medetomidine on Analgesia and Sedation in Rats (Medetomidine의 투여가 흰쥐의 진통과 진정효과에 미치는 영향)

  • Jang, Hwan-Soo;Lee, Maan-Gee
    • Journal of Veterinary Clinics
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    • v.27 no.6
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    • pp.674-678
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    • 2010
  • The effects of medetomidine on the degree of analgesia and sedation in rats were evaluated. The rats were randomly divided into six groups: saline, 1 mL/kg (group 'Saline'); butorphanol, 2.0 mg/kg; medetomidine, 0.2, 0.4, 0.8 or 1.6 mg/kg (group 'MED0.2', 'MED0.4', 'MED0.8' and 'MED1.6', respectively). The degree of analgesia was measured in the $50^{\circ}C$ hot-water tail-flick latency test, and the degree of sedation was evaluated using the numerical sedation score (NSS) and the righting reflex. All doses of medetomidine, except MED0.2, significantly increased the analgesic effect compared to the Saline group. Variables in the MED0.4 and MED0.8 groups, but not in the MED1.6 group, were significantly increased compared to those in the MED0.2 group. However, analgesia with all doses of medetomidine was not significantly different compared to that with butorphanol. Saline and butorphanol treatments did not induce sedation and loss of righting reflex during the recording period. NSS in the MED0.4, MED0.8 and MED1.6 groups were significantly higher than that in the MED0.2 group. NSS in the MED0.8 and MED1.6 groups were not significantly different from that in the MED0.4 group. The latency to loss of righting reflex in the MED0.8 and MED1.6 groups decreased significantly compared to that in the MED0.2 group. Thus, 0.4 and 0.8 mg/kg of medetomidine provided not only reliable analgesia but also sedation to rats. In conclusion, 0.4 to 0.8 mg/kg medetomidine could be a useful chemical restraint method in rats.