• Title/Summary/Keyword: Carbon monoxide (CO)

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Carbon Monoxide as a Novel Central Pyrogenic Mediator

  • Jang, Choon-Gon;Lee, Seung-Jin;Yang, Sang-In;Kim, Jin-Hak;Sohn, Uy-Dong;Lee, Seok-Yong
    • Archives of Pharmacal Research
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    • v.25 no.3
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    • pp.343-348
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    • 2002
  • Carbon monoxide (CO) are produced by heme oxygenase (HO), and HO was detected in hypothalamus. However, the roles of CO produced in hypothalamus was not fully elucidated. So, we tested the effects of CO on body temperature because preoptic-anterior hypothalamus was known as the presumptive primary fever-producing site. CO-saturated aCSF ($4{\;}{\mu}l$, i.c.v.) and hemin ($10{\;}{\mu}g$, i.c.v.) elicited marked febrile response. Pretreatment with indomethacin completely inhibited CO- and hemin-induced fever. Zinc protoporphyrin-IX ($10{\;}{\mu}g$, i.c.v.) or ODQ ($50{\;}{\mu}g$, i.c.v.) partially reduced hemin-induced febrile response. Dibutyryl-cGMP ($100{\;}{\mu}g$, i.c.v.) produced profound febrile response and this febrile response was attenuated by indomethacin. These results indicate that endogenous CO may have a role as a pyrogenic mediator in CNS and CO-mediated pyresis is dependent on prostaglandin production and partially on activation of soluble guanylate cyclase.

Operational Characteristics of a Carbon Monoxide Laser for Instrumentationand its Applications (레이저 계측용 일산화탄소 레이저의 동작 특성 및 그 응용)

  • 김용평;최종운;김규욱;원종욱
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.07a
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    • pp.33-38
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    • 1990
  • The carbon monoxide laser is one of useful light sources for precision laser instrumentation because of tis high efficiency and wideband characteristics. In this presentation, the liquid nitrogen cooled cw CO laser which is developed in KSRI will be reviewed

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Synthesis of N-Substituted Isoindolin-1-ones via Palladium-Catalyzed Carbonylative Heterocyclization of o-Bromobenzylbromide with Carbon Monoxide and Primary Amines

  • 심상철;Li Hong Jiang;이동엽;조찬식
    • Bulletin of the Korean Chemical Society
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    • v.16 no.11
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    • pp.1064-1067
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    • 1995
  • A convenient method for the synthesis of N-substituted isoindolin-1-ones is disclosed in palladium(0)-catalyzed heterocyclization of o-bromobenzylbromide with carbon monoxide (CO) and primary amines in DMF at 100 ℃.

A Study on Carbon monoxide Gas Sensing Characteristics of Pt-SiC Schottky Diode Schottky Diode (Pt-SiC 쇼트키 다이오드를 이용한 CO Gas 감지 특성에 대한 연구)

  • Nho, I.H.;Lee, J.H.;Yang, S.J.;Jang, S.W.;Kim, C.K.
    • Proceedings of the KIEE Conference
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    • 2001.11a
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    • pp.90-92
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    • 2001
  • Carbon monoxide-sensing behavior of Pt-SiC Schottky diodes. fabricated on the same SiC substrate have been systematically compared and analyzed as a function of carbon monoxide concentrati on and temperature by I-V and ${\Delta}I$-t methods under steady-state and transient condition. Adsorption activation energies of Carbon monoxide on the surface of Pt-SiC Schottky diodes is investigated in a high temperature range ($100{\sim}500^{\circ}C$). The optimal temperature for behavior sensing is $300^{\circ}C$ and saturation concentration is 200 ppm.

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Nitric Oxide Synthase Mediates Carbon Monoxide-Induced Stimulation of L-type Calcium Currents in Human Jejunal Smooth Muscle Cells

  • Lim, In-Ja;Yun, Ji-Hyun;Kim, Seung-Tae;Myung, Soon-Chul;Kim, Tae-Ho;Bang, Hyo-Weon
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.3
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    • pp.161-165
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    • 2004
  • Exogenous carbon monoxide (0.2%) increases L-type calcium $(Ca^{2+})$ current in human jejunal circular smooth muscle cells. The stimulatory effect of carbon monoxide (CO) on L-type $Ca^{2+}$ current is inhibited by pre-application of L-NNA, a classical competitive inhibitor of nitric oxide synthase (NOS) with no significant isoform selectivity (Lim, 2003). In the present study, we investigated which isoform of NOS affected CO induced stimulation of L-type $Ca^{2+}$ current in human jejunal circular smooth muscle cells. Cells were voltage clamped by whole-cell mode patch clamp technique, and membrane currents were recorded with 10 mM barium as the charge carrier. Before the addition of CO, cells were pretreated with each inhibitor of three NOS isoforms for 15 minutes. CO-stimulating effect on L-type $Ca^{2+}$ current was partially blocked by N-(3-(Amino-methyl) benzyl) acetamidine 2HCl (1400W, an iNOS inhibitor). On the other hand, 3-bromo-7-nitroindazole (BNI, a nNOS inhibitor) or $N^5-(1-Iminoethyl)-L-ornithine$ dihydrochloride (L-NIO, an eNOS inhibitor) completely blocked the CO effect. These data suggest that low dose of exogenous CO may stimulate all NOS isoforms to increase L-type $Ca^{2+}$ channel through nitric oxide (NO) pathway in human jejunal circular smooth muscle cells.

Carbon monoxide releasing molecule-2 protects mice against acute kidney injury through inhibition of ER stress

  • Uddin, Md Jamal;Pak, Eun Seon;Ha, Hunjoo
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.5
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    • pp.567-575
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    • 2018
  • Acute kidney injury (AKI), which is defined as a rapid decline of renal function, becomes common and recently recognized to be closely intertwined with chronic kidney diseases. Current treatment for AKI is largely supportive, and endoplasmic reticulum (ER) stress has emerged as a novel mediator of AKI. Since carbon monoxide attenuates ER stress, the objective of the present study aimed to determine the protective effect of carbon monoxide releasing molecule-2 (CORM2) on AKI associated with ER stress. Kidney injury was induced after LPS (15 mg/kg) treatment at 12 to 24 h in C57BL/6J mice. Pretreatment of CORM2 (30 mg/kg) effectively prevented LPS-induced oxidative stress and inflammation during AKI in mice. CORM2 treatment also effectively inhibited LPS-induced ER stress in AKI mice. In order to confirm effect of CO on the pathophysiological role of tubular epithelial cells in AKI, we used mProx24 cells. Pretreatment of CORM2 attenuated LPS-induced ER stress, oxidative stress, and inflammation in mProx24 cells. These data suggest that CO therapy may prevent ER stress-mediated AKI.

PaCO2 at Early Stage is Associated with Adverse Cardiovascular Events in Acute Carbon Monoxide Poisoning (급성 일산화탄소 중독 환자에서 응급실 내원 초기 동맥혈 이산화탄소 분압의 임상적 의미)

  • Yang, Keun Mo;Chun, Byeong Jo;Moon, Jeong Mi;Cho, Young Soo
    • Journal of The Korean Society of Clinical Toxicology
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    • v.17 no.2
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    • pp.86-93
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    • 2019
  • Purpose: The objective was to determine the association between PaCO2 and adverse cardiovascular events (ACVEs) in carbon monoxide (CO)-poisoned patients. Methods: This retrospective study included 194 self-breathing patients after CO poisoning with an indication for hyperbaric oxygen therapy and available arterial blood gas analysis at presentation and 6 hours later. The baseline characteristics and clinical course during hospitalization were collected and compared. The mean PaCO2 during the first 6 hours after presentation was calculated. Results: The incidence rates of moderate (30 mmHg< PaCO2 <35 mmHg) or severe (PaCO2 ≤30 mmHg) hypocapnia at presentation after acute CO poisoning were 40.7% and 26.8%, respectively. The mean PaCO2 during the first 6 hours was 33 (31-36.7) mmHg. The incidence of ACVEs during hospitalization was 50.5%. A significant linear trend in the incidence of ACVEs was observed across the total ranges of PaCO2 variables. In multivariate regression analysis, mean PaCO2 was independently associated with ACVEs (OR 0.798 (95% CI 0.641-0.997)). Conclusion: Mean PaCO2 during the first 6 hours was associated with increased ACVEs. Given the high incidence of ACVEs and PaCO2 derangement and the observed association between PaCO2 and ACVEs, this study suggests that 1) PaCO2 should be monitored at the acute stage to predict and/or prevent ACVEs; and 2) further study is needed to validate this result and investigate early manipulation of PaCO2 as treatment.

An experimental study on emission control of HC and CO due to oxidizing catalyst (산화촉매에 의한 자동차 배출가스중 HC 및 CO의 정화에 관한 실험적 연구)

  • 한영출;최규훈
    • Journal of the korean Society of Automotive Engineers
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    • v.3 no.1
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    • pp.46-53
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    • 1981
  • This paper describes emission control of hydrocarbon and carbon-monoxide due to oxidizing catalyst. The experiment was performed on a precious metal pelleted catalyst(Pt). The factors of the efficiency for purification due to oxidizing catalyst are space velocity, temperature, composition of exhaust gas and supplementary air. The experiment was carried out to control the factors of efficiency for purification. The results of experimental study show that temperature of catalytic converter, supplementary air and space velocity affected the efficiency for purification of hydrocarbon and carbon monoxide.

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Carbon Monoxide Sensor Based on a B2HDDT-doped PEDOT:PSS Layer

  • Memarzadeh, R.;Noh, Hui-Bog;Javadpour, S.;Panahi, F.;Feizpour, A.;Shim, Yoon-Bo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2291-2296
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    • 2013
  • An efficient carbon monoxide (CO) sensor was developed based on poly(3,4-ethylenedioxy)thiophenepoly(styrenesulfonate) (PEDOT:PSS) modified with a new pyrimidine-fused heterocyclic compound, bis(2-hydroxyphenyl)dihydropyrido[2,3-d:6,5-d]dipyrimidine-tetraone (B2HDDT). B2HDDT remains stable in the polymer matrix through interactions with functional groups of the polymer. It created prominent sites that captured CO gas, and the experimental parameters, including the amount of doped B2HDDT in the PEDOT:PSS film, were optimized. The sensor probe was also examined to verify its reliability for detecting CO in the presence of atmospheric gases in a discriminating manner. NMR, AFM, and FT-IR spectra were obtained to evaluate the structure and morphology of the B2HDDT-doped PEDOT:PSS (PEDOT:PSS/B2HDDT) film. The content of 35 vol % B2HDDT (7.0 mM) in PEDOT:PSS provided the largest response factor (${\Delta}R/R_o$) for the CO gas. The sensor response was reproducible, with a relative standard deviation < 5% (n = 5). The detection limit was determined to be $0.44{\pm}0.05$ vol %.

Effect of Potassium Promoter on the Adsorption of Carbon Monoxide on Silica Supported Ruthenium

  • Lee, Jo-Woong;Chang, Sei-Hun;Pak, Hyung-Suk;Shin, Kook-Joe;Kim, Myung-Kun;Chung, Won-Il
    • Bulletin of the Korean Chemical Society
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    • v.9 no.3
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    • pp.137-143
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    • 1988
  • We have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported ruthenium with and without potassium coating within the frequency range of 1800-2200 $cm^{-1}$ at various ruthenium concentrations and CO pressures. For the system without potassium coating, three bands were observed in the infrared spectra when CO was adsorbed on both the reduced and oxidized form of supported ruthenium. However, the relative intensities of these three bands were found to have no interdependence. Therefore, we have assigned each of these bands as arising from the CO stretching vibration for carbon monoxide molecules adsorbed on the Ru sites of different nature. On coating with potassium, the 2030 $cm^{-1}$ band observed for the system without potassium coating was found to suffer red shift by 10-30 $cm^{-1}$ and we conclude that this bathochromic shift is caused by enhancement in the capability of back donation of electrons from the metal atom to the antibonding ${\pi}{\ast}$ orbitals of CO due to the presence of potassium.