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  • [期刊] Total Blood Carbon Monoxide: Alternative to Carboxyhemoglobin as Biological Marker for Carbon Monoxide Poisoning Determination
    摘要:As one of the most abundant toxic contaminants in the atmosphere, carbon monoxide (CO) plays a significant role in toxicology and public health. Every year, around half of the accidental non-fire-related poisoning deaths are attributed to CO in the USA, UK and many other countries. However, due to the non-specificity of the symptoms and often encountered inconsistency of these with the results obtained from measurements of the biomarker for CO poisonings, carboxyhemoglobin (COHb), there is a high rate of misdiagnoses. The mechanism of toxicity of CO includes not only the reduced transport of oxygen caused by COHb but also the impairment of cellular respiration and activation of oxidative metabolism by binding to other proteins. Therefore, in this study we propose the measurement of the total amount of CO in blood (TBCO) by airtight gas syringe-gas chromatography-mass spectrometry (AGS-GC-MS) as an alternative to COHb for the determination of CO exposures. The method is validated for a clinical range with TBCO concentrations of 1.63-104 nmol/mL of headspace (HS) (0.65-41.6 mol/mL blood). The limit of quantification was found between 2 and 5 nmol/mL HS (0.8 and 2 mol/mL blood). The method is applied to a cohort of 13 patients, who were exposed to CO under controlled conditions, and the results are compared to those obtained by CO-oximetry. Furthermore, samples were compared before and after a flushing step to remove excess CO. Results showed a significant decrease in TBCO when samples were flushed (10-60%), whereas no constant trend was observed for COHb. Therefore, measurement of TBCO by AGS-GC-MS suggests the presence of more dissolved CO than previously known. This constitutes a first step into the acknowledgment of a possibly significant amount of CO present not in the form of COHb, but as free CO, which might help explain the incongruences with symptoms and decrease misdiagnoses.
  • [期刊] Silicene nanoribbons as carbon monoxide nanosensors with molecular resolution
  • [期刊] Palladium-Catalyzed Addition of Carbon Monoxide and Carbon Tetrachloride to 1-Octene in Supercritical Carbon Dioxide
    摘要:The Pd-catalyzed addition of carbon monoxide and carbon tetrachloride to 1-octene gave coadduct [alkyl 2-( 2, 2, 2-trichloroethyl)octanoate] as the major product in supercritical carbon dioxide by using pyridine as the base. It was found that the selectivity and the yield of coadduct were greatly affected by the pressure of carbon dioxide, the reaction temperature and the amounts of alcohol and base used.
  • [期刊] 急性一氧化碳中毒对大鼠少突胶质细胞前体细胞活性及增殖能力的影响
    摘要:目的 探讨急性一氧化碳中毒(acute carbon monoxide poisoning,ACOP)对大鼠少突胶质细胞前体细胞(oligodendrocyte precursors,OPCs)活性及增殖能力的影响.方法 选取实验用SD新生大鼠24只,取脑后,采用差速贴壁法体外纯化和培养大鼠OPCs完成后,按照数字表法随机分成对照组和ACOP组,每组12只.ACOP组将OPCs放置于密闭容器内,根据体积比注入1%的CO,处理6、24和48 h后分别利用免疫荧光细胞化学法观察OPCs形态和数量,MTT法检测OPCs活性,Brdu染色检测OPCs增殖情况.结果 与对照组相比,ACOP组OPCs胞体呈扁平状、皱缩,突起数目减少、变短,且数量减少;ACOP组6h时OPCs活性无明显改变,24、48 h时细胞活性明显降低(P<0.05),其中48 h细胞活力降低最显著;ACOP组6h时OPCs的Brdu阳性率明显升高(P<0.05),24h时2组无明显差异(P>0.05),48 h时Brdu阳性率较对照组显著降低(P<0.05).结论 ACOP对OPCs造成不可逆性损伤,显著影响其活性和增殖能力,了解其作用机制对一氧化碳中毒迟发性脑病(delayed encephalopathy after acute carbon monoxide poisoning,DEACMP)及寻找其更有效的治疗方法具有重要意义.
  • [期刊] Ten Days of Intermittent, Low-dose Carbon Monoxide Inhalation does not Significantly Alter Hemoglobin Mass, Aerobic Performance Predictors, or Peak-power Exercise Tolerance
    摘要:Carbon monoxide (CO) rebreathing procedures are used to assess hemoglobin mass (Hbmass) but recent evidence suggests that CO is a signaling molecule that may alter physiological functions. We examined the effects of 10 days of intermittent, low-dose CO inhalation on Hbmass, aerobic performance predictors, and peak-power exercise tolerance. 18 recreationally-active men were randomized to either CO or placebo inhalation groups in a single-blind, pre-post parallel-groups trial. Primary outcomes were assessed before and after an intervention period during which subjects inhaled a bolus of 1.2 ml kg(-1) CO or placebo (room air) for 30 s, once per day on 10 days over a 12-day period. Cycling tests were performed >16 h following CO inhalation to exclude acute effects of CO exposure. CO inhalation elevated carboxyhemoglobin by 4.4 +/- 0.4 % (mean +/- SD) following each exposure. Compared to placebo, chronic CO inhalation did not significantly alter Hbmass (p = 0.99), peak oxygen uptake (p = 0.59), peak power output (p = 0.10), submaximal oxygen uptake (p = 0.91), submaximal RER (p = 0.22), lactate threshold (p = 0.65), or peakpower exercise tolerance (p = 0.60). In conclusion, our data support the ability to perform repeated measurements of Hbmass using CO rebreathing over a 12-day period without altering physiological responses.
  • [期刊] Functionalization of Carbon Monoxide and tert-Butyl Nitrile by Intramolecular Proton Transfer in a Bis(Phosphido) Thorium Complex
    摘要:We report intramolecular proton transfer reactions to functionalize carbon monoxide and tert-butyl nitrile from a bis(phosphido) thorium complex. The reaction of (C5Me5)(2)Th[PH(Mes)](2), Mes = 2,4,6-Me3C6H2, with 1 atm of CO yields (C5Me5)(2)Th(kappa(2)-(O,O)-OCH(2)PMes-C(O)PMes), in which one CO molecule is inserted into each thorium-phosphorus bond. Concomitant transfer of two protons, formerly coordinated to phosphorus, are now bound to one of the carbon atoms from one of the inserted CO molecules. DFT calculations were employed to determine the lowest energy pathway. With tert-butyl nitrile, (BuCN)-Bu-t, only one nitrile inserts into a thorium-phosphorus bond, but the proton is transferred to nitrogen with one phosphido remaining unperturbed affording (C5Me5)(2)Th[PH(Mes)][kappa(2)-(P,N)-N(H)C(CMe3)P(Mes)]. Surprisingly, reaction of this compound with KN(SiMe3)(2) removes the proton bound to nitrogen, not phosphorus.
  • [期刊] Transfer coefficients better reflect emphysematous changes than carbon monoxide diffusing capacity in obstructive lung diseases
    摘要:The overlap between asthma and chronic obstructive pulmonary disease (COPD) has attracted the interest of pulmonary physicians; thus, measurement of carbon monoxide diffusion capacity (DLco) and/or transfer coefficients (Kco, DLco/V-A) may become valuable in clinical settings. How these parameters behave in chronic obstructive lung diseases is poorly understood. We predicted that Kco might more accurately reflect emphysematous changes in the lungs than DLco. We examined DLco and Kco in nonsmokers and smokers with asthma and investigated their relationships with forced expiratory volume in 1 s (%FEV1) by group. We then selected nonsmokers (As-NS) and smokers with asthma (As-Sm) in both groups and those with COPD while controlling for the degree of airflow limitation across groups. Emphysema volumes [%lung attenuation volume (%LAV)] and percentage of cross-sectional area of small pulmonary vessels <5 mm(2) (%CSA(<5)) were measured by computed tomography. In As-NS, %Kco was significantly higher when FEN1 % was reduced, but such a correlation was not seen in As-Sm. %Kco successfully differentiated among the three groups when airflow limitation levels were matched. However, %DLc, was significantly reduced only in patients with COPD. Both %LAV and %CSA(<5) were better correlated with %Kco than with %DLco. There was discordance between %DLco and %Kco in As-Sm. which was not seen in As-NS. Overall, %Kco better reflects emphysematous changes in obstructive lung diseases than %DLco.
  • [期刊] A highly specific and sensitive ratiometric fluorescent probe for carbon monoxide and its bioimaging applications
    摘要:The sensitive and accurate detection of intracellular gasotransmitter carbon monoxide (CO) is of great significance for unraveling its diverse cellular functions. Herein, we report a simple highly specific and sensitive 4-hydroxynaphthalimide-based ratiometric fluorescent probe Ratio-CO for monitoring CO levels in living cells. Probe Ratio-CO could quantitatively detect CO in the range of 0-50 M by the ratiometric fluorescence spectroscopy method and the detection limit was measured to be about 17.9 nM. Additionally, probe Ratio-CO has been proven to possess preeminent selectivity towards CO over other bioactive species. Most importantly, the excellent response properties of probe Ratio-CO enable its applications in the monitoring of the fluctuations of CO levels in living cells by the ratiometric fluorescence imaging technique, and we thus anticipate that this probe would be a novel tool for further elucidating the biological functions of CO in living systems.
  • [期刊] Low-Temperature Oxidation of Carbon Monoxide: The Synthesis and Properties of a Catalyst Based on Titanium Dioxide, Nanodiamond, and Palladium for CO Oxidation
    摘要:A catalyst based on TiO2 and nanodiamond with a 10 wt % palladium content of the catalyst was synthesized. The effect of the nanodiamond content on the catalytic properties in a reaction of CO oxidation at room temperature and low concentrations of CO (< 100 mg/m(3)) was studied. It was established that, at a nanodiamond content of the catalyst from 7 to 9 wt % and a palladium content of 10 wt %, the rate of CO oxidation reached a maximum, and it was higher by a factor of 2.5 than the rate of CO oxidation on a catalyst based on pure TiO2, which included palladium clusters. With the use of transmission electron microscopy, XRD X-ray diffractometry, and X-ray photoelectron spectroscopy, it was found that the clusters of palladium covered with palladium oxide with an average cluster size of 4 nm were formed on the surface of the TiO2 carrier. It was assumed that the catalyst synthesized is promising for applications in catalytic and photocatalytic air-cleaning systems.
  • [期刊] Short-Term Forecast of the Carbon Monoxide Concentration Over the Moscow Region by COSMO-ART
    摘要:A short-term forecast of the city chemical weather requires real daily data on pollutant emissions. For operational daily forecasts of pollutant concentrations, usually long-term emission averages are used which may differ significantly from real values for a certain day, especially in big cities with intense and variable human activities. The online coupled atmospheric chemical transport model COSMO-ART was implemented for the Moscow region, Russia. A method for calculation of pollutant emissions for short-term forecasting was suggested. In this method, actual emissions for a certain day are obtained from measurements of air pollutant concentrations. It is assumed that the pollutant concentration reflects the spatially averaged intensity of emission sources. We used the observational data of pollutant concentrations from the network of the State Ecological Monitoring System of Moscow City. In order to get a more homogeneous field of data, virtual stations (so-called "bogus data") were added within the areas not covered with observations. The proposed method allows a transformation of the hourly measurements of air pollutant concentration to emission values just after the measurements are completed. We showed the application of this method for carbon monoxide. Verification of COSMO-ART results demonstrates that the forecasts based on emissions calculated by the new method are better than the ones based on climate mean emissions. The approach suggested in the study provides a possibility to issue more detailed operational short-term forecasts of pollutant concentrations for megacities depending on the real air pollution of the previous day. The main limitation of this methodology is that it can be applied to the chemical species that have longer chemical life-time compared to the frequency of concentration measurements.

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