• Title/Summary/Keyword: anti-decaying

Search Result 5, Processing Time 0.02 seconds

Intravenous Administration of Substance P Attenuates Mechanical Allodynia Following Nerve Injury by Regulating Neuropathic Pain-Related Factors

  • Chung, Eunkyung;Yoon, Tae Gyoon;Kim, Sumin;Kang, Moonkyu;Kim, Hyun Jeong;Son, Youngsook
    • Biomolecules & Therapeutics
    • /
    • v.25 no.3
    • /
    • pp.259-265
    • /
    • 2017
  • This study aimed to investigate the analgesic effect of substance P (SP) in an animal model of neuropathic pain. An experimental model of neuropathic pain, the chronic constriction injury (CCI) model, was established using ICR mice. An intravenous (i.v.) injection of SP (1 nmole/kg) was administered to the mice to examine the analgesic effects of systemic SP on neuropathic pain. Behavioral testing and immunostaining was performed following treatment of the CCI model with SP. SP attenuated mechanical allodynia in a time-dependent manner, beginning at 1 h following administration, peaking at 1 day post-injection, and decaying by 3 days post-injection. The second injection of SP also increased the threshold of mechanical allodynia, with the effects peaking on day 1 and decaying by day 3. A reduction in phospho-ERK and glial fibrillary acidic protein (GFAP) accompanied the attenuation of mechanical allodynia. We have shown for the first time that i.v. administration of substance P attenuated mechanical allodynia in the maintenance phase of neuropathic pain using von Frey's test, and simultaneously reduced levels of phospho-ERK and GFAP, which are representative biochemical markers of neuropathic pain. Importantly, glial cells in the dorsal horn of the spinal cord (L4-L5) of SP-treated CCI mice, expressed the anti-inflammatory cytokine, IL-10, which was not seen in vehicle saline-treated mice. Thus, i.v. administration of substance P may be beneficial for improving the treatment of patients with neuropathic pain, since it decreases the activity of nociceptive factors and increases the expression of anti-nociceptive factors.

A distance Relaying Algorithm Based on Numerical Solution of a Differential Equation for Transmission Line Protection (송전선 보호용 적분근사 거리계전 알고리즘)

  • 조경래;정병태;홍준희;박종근
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.43 no.5
    • /
    • pp.711-720
    • /
    • 1994
  • A distance relaying algorithm for detecting faults at power transmission line is presented in this paper. The algorithm is based on differential equation from relaton between voltage and current, which is composed of lumped resistance and inductance. During the fault transient state,the voltage and current signals are severely distorted due to the exponentially decaying DC offset and high frequency components, In spite of using small data, the presented integral method to evaluate R and L from voltage and current has high performance against these harmonics including DC offset. Therefore, the presented algorithm can be implemented with only a low order anti-aliasing analog filter and dosen't need any digital filter to remove specific components.

  • PDF

A Study on Viscous Damping System of a Ship with Anti-Rolling Pendulum (안티롤링 진자를 장치한 선박의 점성감쇠계 해석에 대한 연구)

  • Park, Sok-Chu;Jang, Kwang-Ho;Yi, Geum-Joo
    • Journal of Navigation and Port Research
    • /
    • v.41 no.6
    • /
    • pp.365-372
    • /
    • 2017
  • The rolling motion of a floating body makes crews and passengers exhausted and/or applies forces to the structure to cause damage; it might even upset the body. Therefore, almost all ships are equipped with bilge keels for anti-rolling; in special cases, an anti-rolling tank(ART) or fin stabilizer or gyroscope could be installed. But an ART requires a large capacity to install it, and a fin stabilizer and gyroscope need great costs to install and also many expenses to operate. The authors suggest the use of an anti-rolling pendulum(ARP), and they showed that the ARP is effective to reduce rolling by experiments and via a Runge-Kutta analysis. This paper introduces the linearized 2 degrees of freedom with a viscous damping system for a ship equipped with ARP; it also shows the validation of the linearized analysis for the ship's roll motion. The paper proposes an optimum ARP on the basis of the justified model. The case of the 7.7kg model with ship 20g ARP of a mass ratio of 0.26%, is the most effective for reducing roll motion. The paper shows the ARPs with various mass ratios are effective for reducing the roll motion of a ship by free decaying roll experiments.

Bioactivities of Several Functional Hardwood Trees (기능성 활엽수종의 생리활성)

  • Bae, Young-Soo;Ham, Yeon-Ho
    • Journal of the Korean Wood Science and Technology
    • /
    • v.28 no.2
    • /
    • pp.66-74
    • /
    • 2000
  • Wood of black locust(Robinia pseudoacacia) and bark of poplar(Populus alba x glandulosa), ash(Fraxinus rhynchophylla) and elm(Ulmus davidiana var. japonica) trees were collected, extracted with acetone-$H_2O$(7:3. v/v), fractionated with hexane, chloroform, ethylacetate and $H_2O$. then freeze dried to get some dark brown powder for bioactive tests. Decay-resistant activity was tested using wood block specimens from the hardwood trees and expressed by weight loss rate. Black locust specimens indicated the best anti-decaying property and poplar blocks were the worst. Antimicrobial and antioxidant activities were also investigated against each wood or bark extractives. Antifungal and antibacterial activities did not indicate any significant differences among the tested fractions. In antioxidant activity. ${\alpha}$-tocopherol one of natural antioxidants. and BHT, one of synthetic antioxidants, were used as references to compare with the antioxidant activities of the extracted fractions. Ethylacetate fraction of ash bark indicated the highest activity besides BHT in this test and all fractions of black locust extractives also indicated higher activities compared with the other fractions.

  • PDF

Bioactivities and Isolation of Functional Compounds from Decay-Resistant Hardwood Species (고내후성 활엽수종의 추출성분을 이용한 신기능성 물질의 분리 및 생리활성)

  • 배영수;이상용;오덕환;최돈하;김영균
    • Journal of Korea Foresty Energy
    • /
    • v.19 no.2
    • /
    • pp.93-101
    • /
    • 2000
  • Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

  • PDF