• Title/Summary/Keyword: Mechanical pretreatment

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Participation of central GABAA receptors in the trigeminal processing of mechanical allodynia in rats

  • Kim, Min Ji;Park, Young Hong;Yang, Kui Ye;Ju, Jin Sook;Bae, Yong Chul;Han, Seong Kyu;Ahn, Dong Kuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.1
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    • pp.65-74
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    • 2017
  • Here we investigated the central processing mechanisms of mechanical allodynia and found a direct excitatory link with low-threshold input to nociceptive neurons. Experiments were performed on male Sprague-Dawley rats weighing 230-280 g. Subcutaneous injection of interleukin 1 beta ($IL-1{\beta}$) ($1ng/10{\mu}L$) was used to produce mechanical allodynia and thermal hyperalgesia. Intracisternal administration of bicuculline, a gamma aminobutyric acid A ($GABA_A$) receptor antagonist, produced mechanical allodynia in the orofacial area under normal conditions. However, intracisternal administration of bicuculline (50 ng) produced a paradoxical anti-allodynic effect under inflammatory pain conditions. Pretreatment with resiniferatoxin (RTX), which depletes capsaicin receptor protein in primary afferent fibers, did not alter the paradoxical anti-allodynic effects produced by the intracisternal injection of bicuculline. Intracisternal injection of bumetanide, an Na-K-Cl cotransporter (NKCC 1) inhibitor, reversed the $IL-1{\beta}$-induced mechanical allodynia. In the control group, application of GABA ($100{\mu}M$) or muscimol ($3{\mu}M$) led to membrane hyperpolarization in gramicidin perforated current clamp mode. However, in some neurons, application of GABA or muscimol led to membrane depolarization in the $IL-1{\beta}$-treated rats. These results suggest that some large myelinated $A{\beta}$ fibers gain access to the nociceptive system and elicit pain sensation via $GABA_A$ receptors under inflammatory pain conditions.

The Biomass Pre-treatment Effect on the Combustion Characteristics of Coal and Biomass Blends (바이오매스 전처리 기술에 따른 혼소 특성에 관한 실험적 연구)

  • KIM, JONG-HO;PARK, KYEONG-HOON;KIM, GYEONG-MIN;PARK, KYEONG-WON;JEONG, TAE-YONG;LEE, YOUNG-JOO;JEON, CHUNG-HWAN
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.1
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    • pp.81-89
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    • 2018
  • Fuel blend technique is one of the most effective way of using biomass to replace the coal. Many studies on combustion characteristics with coal and biomass blends have been conducted. In this study, char reactivity and emission characteristics of coal (Suek) and biomass (EFB) blends has been investigated by TGA and DTF to evaluate the applicability of the pre-treated (torrefaction, ash removal technology) EFB to pulverized coal boiler. In all blending cases, char reactivity improved as the blending ratio increases (10, 20, and 30%), especially torrefied EFB blended at 30%. Also, unburned carbon decreased as the blending ratio increases in all types of EFB. NOx emission showed the increase and decrease characteristics according to the content of fuel-N of raw EFB and torrefied EFB. But the amount of NOx emission at ashless EFB blends is greater than that of Suek despite of lower fuel-N. It indicated that co-firing effect of using the pretreatment biomass fuel is relatively better than those of the untreated biomass fuel about char reactivity and emission characteristics.

Ononis spinosa alleviated capsaicin-induced mechanical allodynia in a rat model through transient receptor potential vanilloid 1 modulation

  • Jaffal, Sahar Majdi;Al-Najjar, Belal Omar;Abbas, Manal Ahmad
    • The Korean Journal of Pain
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    • v.34 no.3
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    • pp.262-270
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    • 2021
  • Background: Transient receptor potential vanilloid 1 (TRPV1) is a non-selective cation channel implicated in pain sensation in response to heat, protons, and capsaicin (CAPS). It is well established that TRPV1 is involved in mechanical allodynia. This study investigates the effect of Ononis spinosa (Fabaceae) in CAPS-induced mechanical allodynia and its mechanism of action. Methods: Mechanical allodynia was induced by the intraplantar (ipl) injection of 40 ㎍ CAPS into the left hind paw of male Wistar rats. Animals received an ipl injection of 100 ㎍ O. spinosa methanolic leaf extract or 2.5% diclofenac sodium 20 minutes before CAPS injection. Paw withdrawal threshold (PWT) was measured using von Frey filament 30, 90, and 150 minutes after CAPS injection. A molecular docking tool, AutoDock 4.2, was used to study the binding energies and intermolecular interactions between O. spinosa constituents and TRPV1 receptor. Results: The ipsilateral ipl injection of O. spinosa before CAPS injection increased PWT in rats at all time points. O. spinosa decreased mechanical allodynia by 5.35-fold compared to a 3.59-fold decrease produced by diclofenac sodium. The ipsilateral pretreatment with TRPV1 antagonist (300 ㎍ 4-[3-Chloro-2-pyridinyl]-N-[4-[1,1-dimethylethyl] phenyl]-1-piperazinecarboxamide [BCTC]) as well as the β2-adrenoreceptor antagonist (150 ㎍ butoxamine) attenuated the action of O. spinosa. Depending on molecular docking results, the activity of the extract could be attributed to the bindings of campesterol, stigmasterol, and ononin compounds to TRPV1. Conclusions: O. spinosa alleviated CAPS-induced mechanical allodynia through 2 mechanisms: the direct modulation of TRPV1 and the involvement of β2 adrenoreceptor signaling.

Effect of Heat Treatment on Mechanical Properties of Cross-Linked Ultra-High Molecular Weight Polyethylene Used for Artificial Joint Liner (인공관절 라이너용 가교된 초고분자량폴리에틸렌(UHMWPE)의 열처리 조건에 따른 기계적 특성 변화)

  • Kim, Hyun-Mook;Kim, Dong-Hoon;Gu, Ja-Uk;Choi, Nak-Sam;Kim, Sung-Kon
    • Composites Research
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    • v.22 no.2
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    • pp.1-6
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    • 2009
  • The mechanical characteristics of gamma-ray irradiated UHMWPE specimens were investigated under various heat treatment conditions. The heat treatment was performed in the range of annealing and remelting temperatures. The annealing treatment below the temperature of $130^{\circ}C$ hardly induced changes in the tensile strength, the strain at the failure and the hardness. However the remelting treatment above $140^{\circ}C$ deteriorated those mechanical properties. It was shown in an FTIR analysis that the annealing treatment caused some oxidation of free radicals created by the pretreatment of the irradiation. These quantitative data represented by the behavior of mechanical properties might be used as basic informations for the design and analysis of various artificial joints.

Effect of Sonication and Reducing Agent Addition on Soil Washing of Heavy Metals-contaminated Soil (초음파 및 환원제 첨가가 중금속 오염토양의 토양세척에 미치는 영향)

  • Hwang, Seon-Suk;Park, Joon-Seok;NamKoong, Wan
    • Journal of Environmental Health Sciences
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    • v.33 no.1 s.94
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    • pp.75-81
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    • 2007
  • This research was conducted to estimate the effect of sonication and reducing agent addition on soil washing of heavy metals-contaminated soil. Sonication trained in soil washing did not significantly increased extraction efficiency of heavy metal compared to soil washing only. The extraction efficiency of sonication trained in soil washing was 12% increased for Pb in 0.01M EDTA leaching solution. Pb and Cd showed higher extraction efficiency in case of reducing agent treatment with mechanical shaking than that with sonication. However, the extraction efficiency of Cu and Zn in case of reducing agent treatment with sonication was over 2 times higher than that in with soil washing. Therefore, application of reducing agent addition with sonication or mechanical shaking should be decided differently for pretreatment of soil washing, according to the kind of heavy metal. It was estimated that sonication after adding reducing agent could increase removal efficiency of Zn or Cu-contaminated soil and shorten the treatment time.

Acupuncture analgesia in a rat model of neuropathic pain (Neuropathic pain을 일으킨 쥐에 있어서 침의 진통작용)

  • Lim, Kyu-sang
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.12 no.1
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    • pp.143-153
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    • 1999
  • Background: The vasoreactivity of cerebral artery is currently the subject of increasing interest Transcranial Doppler The purpose of this study was to investigate the analgesic effect of acupuncture in a model of neuropathic pain produced by segmental spinal nerve injury (SSI) in rats. The left L5 and L6 spinal nerves of Sprague-Dawley rats were tightly ligated, and one week later, manual or electro-acupuncture was applied for 30 minutes to the contralateral hindlimb (right side) while the animal was lightly anesthetized with halothane. The mechanical threshold of the paw for ipsilateral (left side) hind limb flinching was determined prior to and 0.5, 1, 2, 4, and 24 hours after termination of acupuncture. The mechanical threshold for flinching was significantly elevated for about 4 hours after manual acupuncture applied to the BL. 60 (Kunlun) point or electro-acupuncture to the BL. 60 and BL. 40 (Weizhong) points. However, manual acupuncture applied to the ST. 36 (Zusanli) point was not effective. Furthermore, systemic naloxone pretreatment had no effect on the acupuncture induced threshold elevation. These data suggests that acupuncture produces a point specific, naloxone independent analgesia in a rat neuropathic pain model. ※ This paper is supported by a grant from the '1996 Jusan Foundation of Wonkwang university.)

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Development of Microfluidic Chip for Enrichment and DNA Extraction of Bacteria Using Concanavalin A Coated Magnetic Particles (Concanavalin A가 코팅 된 자성 입자를 이용한 미생물 농축 및 유전자 추출 칩 개발)

  • Kwon, Kirok;Gwak, Hogyeong;Hyun, Kyung-A;Jung, Hyo-Il
    • Journal of Sensor Science and Technology
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    • v.27 no.4
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    • pp.237-241
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    • 2018
  • The real-time enrichment and detection of pathogens are serious issues and rapidly evolving field of research because of the ability of these pathogens to cause infectious diseases. In general, bacterial detection is accomplished by conventional colony counting or by polymerase chain reaction (PCR) after DNA extraction. As colony counting requires considerable time to cultivate, PCR is an attractive method for rapid detection. A small number of pathogens can cause diseases. Hence, a pretreatment process, such as enrichment is essential for detecting bacteria in an actual environment. Thus, in this study, we developed a microfluidic chip capable of performing rapid enrichment of bacteria and the extraction of their genes. A lectin, i.e., Concanavalin A (ConA), which shows binding affinity to the surface of most bacteria, was coated on the surface of magnetic particles to nonspecifically capture bacteria. It was subsequently concentrated through magnetic forces in a microfluidic channel. To lyse the captured bacteria, magnetic particles were irradiated by a wavelength of 532nm. The photo-thermal effect on the particles was sufficient for extracting DNA, which was consequently utilized for the identification of bacteria. Our device will help monitor the existence of bacteria in various environmental situations such as water, air, and soil.

The Experimental Study of Cheonghunhwadam-tang Gamypang on the Regional Cerebral Blood Flow and Mean Arterial Blood Pressure in Rats(III) (청훈화담탕가미방이 국소뇌혈류량 평균혈압에 미치는 실험적 연구(III))

  • Jeong Hyun Woo;Rho Young Ho;Kim Cheon Joong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.3
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    • pp.746-750
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    • 2003
  • Cheonghunhwadam-tang have been used in oriental medicine for many centuries as a therapeutic agent of vertigo by wind, fire and phlegm. CHT Gamypang(CTG) was CHT adding Aurantii Fructus(AF). The effects of CTG on the regional cerebral blood f1ow(rCBF) and mean arterial blood pressure(MABP) is not known. The mechanical Study of CTG on the cerebral hemodynamics is not known too. Therefore, purpose of this Study was to investigate effects of CTG on the rCBF and MABP, mechanism of CTG on the cerebral hemodynamics in rats. The changes of rCBF and BP was determinated by Laser-Doppler Flowmetry(LDF). The results were as follows ; CTG extract was significantly decreased rCBF in a dose-dependent, but the change of MABP was not shown. Pretreatment with propranolol(3mg/kg, i.v.) was significantly increased CTG(10 mg/kg, i.v.) induced decrease of rCBF. Pretreatment with indomethacin(3mg/kg, i.v.) and methylene blue(10㎍/kg, i.v.) were increased CTG induced decrease of rCBF too. This results suggest that the mechanism of CTG is mediated by adrenergic β - receptor, guanylate cyclase and cyclooxygenase.

Pretreatment of Waste-activated Sludge for Enhancement of Methane Production (메탄발효 효율향상을 위한 하.폐수 슬러지의 전처리 기술)

  • NamKung, Kyu-Cheol;Jeon, Che-Ok
    • Microbiology and Biotechnology Letters
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    • v.38 no.4
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    • pp.362-372
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    • 2010
  • Although different disposal routes of waste-activated sludge are possible, anaerobic digestion plays an important role for its abilities to further transform organic matter into methane. The potential of using methane as energy source has long been widely recognised and the present paper extensively reviews the principles of anaerobic digestion, the process parameters and hydrolysis. Hydrolysis is recognised as rate-limiting step in the complex digestion process. To accelerate the digestion and enhance the production of biogas, various pre-treatments can be used to improve the rate-limiting hydrolysis. These treatments include mechanical, thermal, chemical and biological interventions to the feedstock. All pre-treatments result in a lysis or disintegration of sludge cells, thus releasing and solubilizing intracellular material into the water phase and transforming refractory organic material into biodegradable species. The reader will finally be guided to extensive discussion for anaerobic digestion processes.

Value-added Utilization of Lignin Residue from Pretreatment Process of Lignocellulosic Biomass (목질계 바이오매스 전처리 공정에서 발생하는 리그닌 부산물 활용 기술 개발 동향)

  • Jung, Jae Yeong;Lee, Yumi;Lee, Eun Yeol
    • Applied Chemistry for Engineering
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    • v.27 no.2
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    • pp.135-144
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    • 2016
  • Due to the high price volatility and environmental concern of petroleum, biofuels such as bioethanol produced from lignocellulosic biomass have attracted much attention. It is also expected that the amount of lignin residue generated from pretreatment of lignocellulosic biomass will increase as the volume of cellulosic bioethanol increases. Lignin is a natural aromatic polymer and has very complex chemical structures with chemical functional groups. Chemical modification of lignin such as oxypropylation and epoxidation has also been applied to the production of value-added bioplastics such as polyurethane and polyester with enhanced thermal and mechanical properties. In addition, lignin can be used for carbon fiber production in automobile industries. This review highlights recent progresses in utilizations and chemical modifications of lignin for the production of bioplastics, resins, and carbon fiber.