aldehydes

醛类
  • 文章类型: Case Reports
    Glutaraldehyde is a kind of volatile and irritating aldehyde organic compound, which belongs to high-efficiency disinfectant. It has a strong stimulating effect on the mucous membranes of the eyes, respiratory tract and digestive tract, and skin causing denaturation, liquefaction and necrosis of mucous membrane proteins. This article analyzes the treatment process of a patient with high-concentration glutaraldehyde poisoning by oral and inhalation, and discusses the clinical manifestations and prognosis of high-concentration glutaraldehyde poisoning, so as to provide a basis for clinical treatment.
    戊二醛是一种易挥发的刺激性醛类有机化合物,属于高效消毒剂,对眼、呼吸道和消化道黏膜及皮肤有强烈的刺激作用,使黏膜蛋白质变性液化坏死。本文对1例口服及吸入高浓度戊二醛中毒患者的救治过程进行分析,探讨高浓度戊二醛中毒的临床表现和转归,为临床治疗提供依据。.
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  • 文章类型: Journal Article
    在这项研究中,介绍了有关橄榄果实中几种生物活性化合物测定的总体调查。开发了两种方法,一种用于测定橄榄果实酚类化合物的UPLC-Q-TOF-MS方法和一种针对色素(叶绿素和类胡萝卜素)测定的HPLC-DAD方法,生育酚(α-,β,-γ,δ-)和角鲨烯。开发了目标和可疑筛查工作流程,以对橄榄的酚类成分进行彻底的指纹识别。两种方法都得到了验证,表现出优异的性能特点,并且可以用作监测橄榄果实样品中生物活性化合物的可靠工具。开发的方法用于化学表征科洛维橄榄品种的果实,起源于莱斯沃斯岛,北爱琴海地区,希腊。用天花苷在Kolovi橄榄中鉴定并定量了25种酚类化合物,羟基酪醇,油精和油分浓度很高。此外,使用内部可疑数据库在样品中鉴定了12种新的生物活性化合物。色素分析结果表明,Kolovi品种应具有低色素沉着的特征,与其他橄榄品种相比,生育酚和角鲨烯含量相对较高。Kolovi橄榄生物活性含量的表征强调了Kolovi橄榄果实的高营养和可能的经济价值。
    In this study, an overall survey regarding the determination of several bioactive compounds in olive fruit is presented. Two methodologies were developed, one UPLC-Q-TOF-MS method for the determination of olive fruit phenolic compounds and one HPLC-DAD methodology targeting the determination of pigments (chlorophylls and carotenoids), tocopherols (α-, β, -γ, δ-) and squalene. Target and suspect screening workflows were developed for the thorough fingerprinting of the phenolic fraction of olives. Both methods were validated, presenting excellent performance characteristics, and can be used as reliable tools for the monitoring of bioactive compounds in olive fruit samples. The developed methodologies were utilized to chemical characterize the fruits of the Kolovi olive variety, originating from the island of Lesvos, North Aegean Region, Greece. Twenty-five phenolic compounds were identified and quantified in Kolovi olives with verbascoside, hydroxytyrosol, oleacein and oleomissional found in significantly high concentrations. Moreover, 12 new bioactive compounds were identified in the samples using an in-house suspect database. The results of pigments analysis suggested that Kolovi variety should be characterized as low pigmentation, while the tocopherol and squalene content was relatively high compared to other olive varieties. The characterization of Kolovi olive bioactive content highlighted the high nutritional and possible economic value of the Kolovi olive fruit.
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  • 文章类型: Journal Article
    Human breath contains a large amount of small volatile organic compounds (VOCs) and could therefore be used as a carrier of metabolic information for medical diagnostics. Still, in spite of several promising techniques that have been applied during the last decades to study breath content, there is a lack of breath-based diagnostic tools available for physicians. Among several promising techniques, infrared (IR) spectroscopy has already proved its potential for reliable detection of VOCs in the breath. However, due to the large dynamic range of molecular concentrations and overlapping absorption spectra of different VOCs, many low-absorption molecules stay hidden in spectroscopic measurements. To overcome this obstacle, we propose the Matryoshka method for removing masking effects and revealing the buried spectral structures in any bio-fluid in the gas phase. By exploiting both physical and digital removal steps, we demonstrate how the method reveals methane, acetone, aldehyde, and methyl butyrate in a real breath.
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  • 文章类型: Journal Article
    Among the numerous unknown metabolites representative of our exposure, focusing on toxic compounds should provide more relevant data to link exposure and health. For that purpose, we developed and applied a global method using data independent acquisition (DIA) in mass spectrometry to profile specifically electrophilic compounds originating metabolites. These compounds are most of the time toxic, due to their chemical reactivity toward nucleophilic sites present in biomacromolecules. The main line of cellular defense against these electrophilic molecules is conjugation to glutathione, then metabolization into mercapturic acid conjugates (MACs). Interestingly, MACs display a characteristic neutral loss in MS/MS experiments that makes it possible to detect all the metabolites displaying this characteristic loss, thanks to the DIA mode, and therefore to highlight the corresponding reactive metabolites. As a proof of concept, our workflow was applied to the toxicological issue of the oxidation of dietary polyunsaturated fatty acids, leading in particular to the formation of toxic alkenals, which lead to MACs upon glutathione conjugation and metabolization. By this way, dozens of MACs were detected and identified. Interestingly, multivariate statistical analyses carried out only on extracted HRMS signals of MACs yield a better characterization of the studied groups compared to results obtained from a classic untargeted metabolomics approach.
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  • 文章类型: Journal Article
    Substrate inhibition by the aldehyde has been observed for decades in NAD(P)+-dependent aldehyde dehydrogenase (ALDH) enzymes, which follow a Bi Bi ordered steady-state kinetic mechanism. In this work, by using theoretical simulations of different possible substrate inhibition mechanisms in monosubstrate and Bi Bi ordered steady-state reactions, we explored the kind and extent of errors arising when estimating the kinetic parameters and determining the kinetic mechanisms if substrate inhibition is intentionally or unintentionally ignored. We found that, in every mechanism, fitting the initial velocity data of apparently non-inhibitory substrate concentrations to a rectangular hyperbola produces important errors, not only in the estimation of Vmax values, which were underestimated as expected, but, surprisingly, even more in the estimation of Km values, which led to overestimation of the Vmax/Km values. We show that the greater errors in Km arises from fitting data that do experience substrate inhibition, although it may not be evident, to a Michaelis-Menten equation, which causes overestimation of the data at low substrate concentrations. Similarly, we show that if substrate inhibition is not fully assessed when inhibitors are evaluated, the estimated inhibition constants will have significant errors, and the type of inhibition could be grossly mistaken. We exemplify these errors with experimental results obtained with the betaine aldehyde dehydrogenase from spinach showing the errors predicted by the theoretical simulations and that these errors are increased in the presence of NADH, which in this enzyme favors aldehyde substrate inhibition. Therefore, we strongly recommend assessing substrate inhibition by the aldehyde in every ALDH kinetic study, particularly when inhibitors are evaluated. The common practices of using an apparently non-inhibitory concentration range of the aldehyde or a single high concentration of the aldehyde or the coenzyme when varying the other to determine true kinetic parameters should be abandoned.
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  • 文章类型: Journal Article
    这项工作的目的是通过离体方法研究人类老年人唾液的个体差异对香气释放和代谢的影响。从由年龄和性别匹配的110名老年人(年龄>65岁)组成的小组中选择30名患有或不患有唾液分泌不足的个体。然后,他们受刺激的唾液样品在三种芳香化合物(乙基己酸酯,octanal,2-壬酮)进行顶空-气相色谱和液/液萃取-气相色谱质谱分析。这些测定揭示了唾液对芳香化合物的释放和代谢的影响程度高度依赖于化合物的化学家族(辛醛>己酸乙酯>2-壬酮)。此外,对于三种被测定的化合物,与对照组相比,来自分泌分泌抑制剂(HPS)组的唾液表现出较低的释放和/或较高的代谢。关于唾液样本的生化特征,两组总蛋白含量无显著差异。这并不排除特定蛋白质参与需要在进一步实验中澄清的观察结果。HPS组唾液总抗氧化能力明显高于对照组,这表明该参数可能与唾液对芳香化合物的代谢有关。这种作用可能会改变患有唾液分泌不足的个体的香气感知。实际应用:世界人口老龄化如此之快,以至于大多数国家都没有准备好应对这一人口挑战,以非传染性慢性病患病率上升为特征(例如,糖尿病,胃肠道疾病)与饮食模式不足有关。因此,支持均衡饮食是维持良好生活质量的最具成本效益的策略之一。一个合适的饮食需要考虑到两者,特定的感官和营养个体需求。然而,衰老通常伴随着口腔健康的恶化(例如,低唾液分泌物),可以改变味觉和嗅觉的能力。这项工作的结果有助于更好地了解人类唾液在香气释放和代谢中的作用。理解鼻后香气释放和感知的第一步。这些知识将有助于为更好地适应老年人需求的食品配方提出创新的解决方案,从而允许依赖性的延迟发作。
    The aim of this work was to study the effects of interindividual variability of human elderly saliva on aroma release and metabolization by ex vivo approaches. Thirty individuals suffering or not from hyposalivation were selected from a panel formed by 110 elderly people (aged >65 years old) that were matched by age and sex. Then, their stimulated saliva samples were independently incubated in presence of three aroma compounds (ethyl hexanoate, octanal, 2-nonanone) to perform headspace-gas chromatography and liquid/liquid extraction-gas chromatography mass spectrometry analyses. These assays revealed that the extent of saliva effect on the release and metabolization of aroma compounds was highly dependent on the chemical family of the compounds (octanal>ethyl hexanoate>2-nonanone). Moreover, salivas from the hyposalivator (HPS) group exerted a significant lower release and/or higher metabolization than those of the control group for the three assayed compounds. Regarding the biochemical characterization of the saliva samples, no significant differences were found in the total protein content between the two groups. This does not preclude the involvement of specific proteins on the observed results that need to be clarified in further experiments. Saliva from the HPS group presented a significantly higher total antioxidant capacity than that of the control group, which suggests that this parameter could be related to the metabolization of aroma compounds by saliva. Such effects might alter aroma perception in individuals suffering from hyposalivation. PRACTICAL APPLICATIONS: The world population is getting older so fast that most countries are not prepared to handle this demographic challenge, characterized by an increasing prevalence of noncommunicable chronic diseases (e.g., diabetes, gastrointestinal disorders) associated to inadequate eating patterns. Thus, supporting a balanced diet is one of the most cost-effective strategies to maintain a good quality of life. A suitable diet needs to take into account both, specific sensory and nutritional individual needs. However, aging is often accompanied by deterioration in oral health (e.g., low salivary secretions), which could alter the capacities to taste and smell. Results from this work contribute to a better understanding of the role of human saliva in aroma release and metabolization, a first step to comprehend retronasal aroma release and perception. This knowledge will help to propose innovative solutions for the reformulation of food products better adapted to the elderly\'s needs, thus allowing delayed onset of dependency.
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  • 文章类型: Journal Article
    这项研究调查了在4°C下连续储存12个月期间三种光强度对四种类型棕榈油的影响。4-羟基-2-反式-己烯醛(4-HHE)的浓度,4-羟基-2-反式-壬烯醛(4-HNE),油中多环芳烃(PAH)4和PAH8随着储存后光照强度的增加而显著增加。红棕榈油的4-HNE增加率最低,而5°棕榈油的PAH增加率最高,OPAH,4-HNE,和过氧化物值在储存过程中。对于相同类型的油,在储存后6000lx(lx)的光强度下,OPAHs显著增加。9FO浓度的增加,ATQ,和储存在6000lx的油中的BaPO与它们相应的母体PAHs呈正相关,表明PAH氧化发生在6000lx。结果表明,光照强度和β-胡萝卜素可能控制PAHs,OPAHs,和4-羟基-反式-烯烃用于植物油储存,交通运输,和零售。
    This study investigated the effects of three light intensities on four types of palm oils during consecutive storage for 12 months at 4 °C. The concentrations of 4-hydroxy-2- trans-hexenal (4-HHE), 4-hydroxy-2- trans-nonenal (4-HNE), polycyclic aromatic hydrocarbon (PAH)4, and PAH8 in the oils significantly increased with the increasing light intensity after storage. The red palm oil had the lowest rate of increase of 4-HNE, while 5° palm oil had the highest rate of increase of the PAH, OPAH, 4-HNE, and peroxide values during storage. For the same type of oil, OPAHs increased significantly under a light intensity of 6000 lx (lx) after storage. The increasing concentrations of 9FO, ATQ, and BaPO in the oils stored at 6000 lx showed a positive relation to their corresponding parent PAHs, indicating that PAH oxidation occurred at 6000 lx. The results suggest that light intensity and β-carotene may control PAHs, OPAHs, and 4-hydroxy-trans- alkenals for vegetable oil storage, transportation, and retail.
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  • 文章类型: Journal Article
    Our study compared copper (Cu), zinc (Zn) and manganese (Mn), crucial for human normal physio-logy maintenance, and lead (Pb) levels as environmental pollutant, in subjects suffering of deep vein thrombosis of lower limbs (DVTs) vs. healthy subjects. Furthermore, we evaluated oxidative stress parameters, the thiobarbituric acid reactive substances (TBARS) as the sum of malondialdehyde or 1,1,3,3-tetraethoxypropane (MDA) and 4-hydroxynonenal 4-HNE) and cytosolic superoxide dismutase (Cu/Zn-SOD) concentrations in both groups. We recruited 24 DVT cases and 46 healthy subjects as controls. Questionnaire with socio‑demographic, habits and lifestyle were collected. Hair concentrations of Zn, Mn, Cu and Pb were measured by ICP-MS, plasma concentrations of MDA and 4-HNE were measured by HPLC and SOD plasma concentrations were detected by ELISA test. A quantitative and qualitative variables comparison between cases and controls group was made by Mann-Whitney U test and Pearson\'s Chi-square test, respectively. We found low concentrations of Zn, Mn and Cu vs. high Pb concentrations in DVTs subjects. TBARS were found higher in the cases group, conversely, SOD concentrations were found lower in cases with respect to controls. Furthermore, we found the diet of pathological subjects significantly deficient in vegetables. These results are indicative of a lower enzymatic activity in patients, related to low transition metal levels in the DVTs and high levels of Pb, coupled with an unbalanced diet.
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  • 文章类型: Journal Article
    The three-component reaction of indole, isobutyraldehyde, and methyl acetoacetate affords methyl 2-(acetyl)-3-(1H-indol-3-yl)-4-methylpentanoate as a single diastereomer. To investigate the origin of the observed diastereoselectivity, the thermodynamics and kinetics of interconversion of diastereomers 1 and 2 in solution were studied by a combination of (1)H nuclear magnetic resonance (NMR) spectroscopy, high-performance liquid chromatography (HPLC), mass spectrometry, and deuteration experiments. The results indicate that interconversion is both acid- and base-catalyzed, and that the alpha carbon is the only stereolabile center in the molecule. The evidence points to an enolization mechanism for the interconversion process. The selective precipitation of 1 in the presence of the equilibrium 1⇆2 eventually results in the exclusive formation of 1 (crystallization-induced asymmetric transformation).
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  • 文章类型: Journal Article
    这项研究是为了表征三种关注健康的醛(甲醛,乙醛,和丙烯醛)在2008年夏季和初秋(6月至10月)的北京中心站点。污染环境中的醛来自主要和次要来源,这限制了这些反应性化合物的控制策略。测量是以前做的,during,以及在北京奥运会之后,研究奥运会期间实施的戏剧性空气污染控制措施是否对三种醛的浓度及其潜在的主要和次要来源产生了影响。甲醛的平均浓度,乙醛和丙烯醛分别为29.3±15.1μg/m3,27.1±15.7μg/m3和2.3±1.0μg/m3,在整个测量期间,在光化学烟雾季节,所有这些都处于世界各地城市测得的浓度范围的高端。与奥运会前相比,污染控制期间甲醛和丙烯醛增加,跟随温度的变化,并且与臭氧和通过主成分分析(PCA)确定的次要形成因子显着相关。相比之下,与奥运会前相比,奥运会空气污染控制期间乙醛的平均浓度有所降低,并且与当地排放源排放的几种污染物显着相关(例如,NO2,CO,和PM2.5)。乙醛也与主要排放源密切相关,包括通过PCA确定的植物燃烧和石油燃烧因素。与奥运会前和奥运会期间相比,在奥运会后的采样期间,所有三种醛均较低,可能是由于季节性和区域性影响。我们的发现指出了二次污染物源控制策略的复杂性。
    This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.3±15.1 μg/m3, 27.1±15.7 μg/m3 and 2.3±1.0 μg/m3, respectively, for the entire period of measurements, all being at the high end of concentration ranges measured in cities around the world in photochemical smog seasons. Formaldehyde and acrolein increased during the pollution control period compared to the pre-Olympic Games, followed the changing pattern of temperature, and were significantly correlated with ozone and with a secondary formation factor identified by principal component analysis (PCA). In contrast, acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period and was significantly correlated with several pollutants emitted from local emission sources (e.g., NO2, CO, and PM2.5). Acetaldehyde was also more strongly associated with primary emission sources including vegetative burning and oil combustion factors identified through the PCA. All three aldehydes were lower during the post-Olympic sampling period compared to the before and during Olympic periods, likely due to seasonal and regional effects. Our findings point to the complexity of source control strategies for secondary pollutants.
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