oxidants

氧化剂
  • 文章类型: Journal Article
    液-液反应在有机合成中起着重要作用。然而,在不相容的两相液体之间的相界面的控制仍然具有挑战性。此外,分离液体酸,来自反应器的碱和氧化剂需要长时间和高成本。为了解决这些问题,我们从活生物体中细胞的结构和功能中获得灵感,并开发了仿生3D打印细胞反应器。蜂窝状反应器容纳含有催化剂或氧化剂的水相,同时浸入有机相反应物中。该设置控制相界面在有机相内的分布并将界面面积增加2.3倍。值得注意的是,完成反应后,从有机相中除去细胞反应器和水相,消除了额外的分离步骤,并防止了反应器和酸性物质之间的直接接触,碱性,或氧化物质。此外,蜂窝反应器提供了数字化设计可行性和具有成本效益的制造优势。
    Liquid-liquid reactions play a significant role in organic synthesis. However, control of the phase interface between incompatible two-phase liquids remains challenging. Moreover, separating liquid acid, base and oxidants from the reactor takes a long time and high cost. To address these issues, we draw inspiration from the structure and function of cells in living organisms and develop a biomimetic 3D-printed cellular reactor. The cellular reactor houses an aqueous phase containing the catalyst or oxidant while immersed in the organic phase reactant. This setup controls the distribution of the phase interface within the organic phase and increases the interface area by 2.3 times. Notably, the cellular reactor and the aqueous phase are removed from the organic phase upon completing the reaction, eliminating additional separation steps and preventing direct contact between the reactor and acidic, alkaline, or oxidizing substances. Furthermore, the cellular reactor offers the advantages of digital design feasibility and cost-effective manufacturing.
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  • 文章类型: Journal Article
    背景:无法解释的不孕症被定义为在无保护的性交1年后无法怀孕的夫妇进行的基本评估中没有任何病理。检查不孕症原因的测试结果显示,近15%的夫妇没有可识别的原因。
    目的:本研究的目的是研究活性氧(ROS)对妊娠和胚胎的影响。
    方法:这项研究包括200名患者,年龄在20-44岁之间,无法解释的不孕症,反复宫腔内人工授精失败,因此开始进行体外受精(IVF)/卵胞浆内单精子注射治疗。胚胎学家在取卵过程中从这些患者的卵母细胞中收集了一些废弃的卵泡液样品。接下来,总抗氧化剂状态(TAS),总氧化剂状态(TOS),和氧化应激指数(OSI)值在生物化学实验室计算。
    结果:就怀孕状况而言,生化和临床妊娠患者的卵泡TOS和OSI值没有显着差异,而妊娠患者的TAS值明显高于妊娠患者(P<0.05)。就胚胎质量而言,在TAS中没有观察到显著差异,TOS,和OSI值在1级和2级胚胎之间,而接受1级胚胎移植的患者的妊娠率显着较高(P<0.05)。然而,吸烟患者的卵泡液TAS水平显著低于不吸烟患者;TOS和OSI水平显著高于不吸烟患者.
    结论:这项研究表明,暴露于氧化应激可能是不孕症的一个致病因素。此外,ROS通过增加卵泡液中的OSI来降低TAS的水平;因此,抗氧化剂补充可能是必要的。
    BACKGROUND: Unexplained infertility is defined as the absence of any pathology in the basic evaluation performed in couples who cannot achieve pregnancy after 1 year of unprotected sexual intercourse. The results of tests examining the causes of infertility show no identifiable cause in almost 15% of couples.
    OBJECTIVE: The aim of this study was to investigate the effects of reactive oxygen species (ROS) on pregnancy and embryos.
    METHODS: This study included 200 patients, aged between 20-44 years, with unexplained infertility, who had recurrent intrauterine inseminations failures and hence started in vitro fertilization (IVF)/intracytoplasmic sperm injection treatment. Some amounts of waste follicular fluid samples were collected by embryologists from the oocytes of these patients during the ovum pick-up procedure. Next, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) values were calculated in the biochemistry laboratory.
    RESULTS: In terms of pregnancy status, both follicular TOS and OSI values were not significantly different in patients with biochemical and clinical pregnancy, whereas TAS values were significantly higher in patients with pregnancy (P < 0.05). In terms of embryo quality, no significant difference was observed in TAS, TOS, and OSI values between grade 1 and 2 embryos, whereas pregnancy rates were significantly higher in patients who received grade 1 embryo transfer (P < 0.05). However, the follicular fluid TAS levels were significantly lower in smoking patients than in those who did not smoke; TOS and OSI levels were significantly higher.
    CONCLUSIONS: This study showed that exposure to oxidative stress might be a causative factor for infertility. In addition, ROS decreased the level of TAS by increasing OSI in the follicular fluid; thus, antioxidant supplementation might be a necessity.
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  • 文章类型: Journal Article
    这项研究调查了CD8+T细胞活化后数小时内DNA甲基化的复杂动态,在一个关键但研究不足的时间窗口。DNA甲基化是调节基因表达和指导免疫反应的核心表观遗传修饰。我们的调查跨越了激活后96小时,并揭示了全球和位点特异性甲基化变化的细微差别。我们确定了15,626个显着的差异甲基化CpG分布在整个基因组中,最显著的变化发生在基因ADAM10、ICA1和LAPTM5内。虽然许多变化具有适度的效应大小,大约120个CpG表现出高于1.5的log2FC,其中细胞活化和增殖途径受影响最大。相对较少的差异甲基化CpG沿着相邻的基因区域发生。例外是七个差异甲基化基因区域,人类T细胞受体α连接基因在3kb窗口内表现出一致的甲基化变化。我们还研究了炎症环境是否可以在激活过程中改变DNA甲基化,增殖细胞暴露于氧化剂甘氨酸氯胺。在这种情况下没有观察到实质性的差异甲基化。早期激活的时间视角为表观遗传免疫学的发展领域增加了深度,提供具有治疗创新意义的见解,并扩大我们对免疫功能中表观遗传调节的理解。
    This research investigates the intricate dynamics of DNA methylation in the hours following CD8+ T cell activation, during a critical yet understudied temporal window. DNA methylation is an epigenetic modification central to regulation of gene expression and directing immune responses. Our investigation spanned 96-h post-activation and unveils a nuanced tapestry of global and site-specific methylation changes. We identified 15,626 significant differentially methylated CpGs spread across the genome, with the most significant changes occurring within the genes ADAM10, ICA1, and LAPTM5. While many changes had modest effect sizes, approximately 120 CpGs exhibited a log2FC above 1.5, with cell activation and proliferation pathways the most affected. Relatively few of the differentially methylated CpGs occurred along adjacent gene regions. The exceptions were seven differentially methylated gene regions, with the Human T cell Receptor Alpha Joining Genes demonstrating consistent methylation change over a 3kb window. We also investigated whether an inflammatory environment could alter DNA methylation during activation, with proliferating cells exposed to the oxidant glycine chloramine. No substantial differential methylation was observed in this context. The temporal perspective of early activation adds depth to the evolving field of epigenetic immunology, offering insights with implications for therapeutic innovation and expanding our understanding of epigenetic modulation in immune function.
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  • 文章类型: Editorial
    暂无摘要。
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  • 文章类型: Journal Article
    背景:牙周病是猫中最常见的诊断问题。众所周知,牙周疾病不仅会引起各种口腔健康问题,而且还会导致全身性疾病。氧化应激可能是全身性疾病和牙周炎之间的联系。我们的研究旨在说明牙周炎对猫氧化应激发展的影响。此外,研究了牙龈细菌菌群的变化。
    方法:基于临床和实验室检查,将50只猫分为正常(n=25)和中度至晚期牙周炎(n=25)两组。血清总抗氧化能力(TAC),总氧化剂状态(TOS),测定还原型(GSH)和氧化型谷胱甘肽(GSSG)。此外,从所有猫的龈下菌斑中取样进行细菌培养。
    结果:血清TOS,GSSG,GSSG与GSH比率,和氧化应激指数(OSI),计算为TOS与TAC的比率在有牙周病的猫明显更高,与对照组相比,TAC显著降低(p<0.05)。细菌培养结果表明,患者分离的菌落数量高于对照组。此外,对这些数据的分析显示,牙周指数与氧化应激呈正相关。
    结论:我们的结果表明,猫的牙周炎与主要的氧化应激有关。此外,氧化剂因素,如TOS和OSI,与抗氧化因子相比,可能更好地表明牙周炎患者存在氧化应激状况。
    BACKGROUND: Periodontal diseases are the most frequently diagnosed problem in cats. It has been well-established that periodontal diseases could not only cause various oral health issues but could also contribute to systemic diseases. Oxidative stress is a possible link between systemic diseases and periodontitis. Our study aimed to illustrate the influence of periodontitis on oxidative stress development in cats. Furthermore, the changes in the bacterial flora of the gums were investigated.
    METHODS: Based on the clinical and laboratory examinations, fifty cats were divided into two groups normal (n = 25) and moderate to advanced periodontitis (n = 25). Serum total antioxidant capacity (TAC), total oxidant status (TOS), reduced (GSH) and oxidized glutathione (GSSG) were measured. In addition, samples were taken from the subgingival plaques of all cats for bacterial culture.
    RESULTS: Serum TOS, GSSG, GSSG to GSH ratio, and oxidative stress index (OSI), calculated as the ratio of TOS to TAC in cats with periodontal disease were significantly higher, and TAC was significantly lower (p < 0.05) compared with controls. The results of bacterial culture indicated that the number of isolated bacterial colonies is higher in patients than in the control group. Additionally, the analysis of these data showed a positive association between periodontal index and oxidative stress.
    CONCLUSIONS: Our results revealed that periodontitis in cats is related to a main oxidative stress. Furthermore, oxidant factors such as TOS and OSI, compared to antioxidant factors, may better indicate the presence of oxidative stress conditions in patients with periodontitis.
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  • 文章类型: Journal Article
    垃圾填埋场附近的地下水污染通常是由渗滤液泄漏引起的,和渗透性反应屏障(PRB)被广泛用于地下水修复。然而,PRB中反应介质的失活和阻塞限制了它们的长期有效性。在目前的研究中,提出了一种新的PRB原位再生方法,以修复渗滤液污染的地下水。将CO2与氧化剂结合用于填料的分散和再生;通过注入CO2以分散填料,PRB的渗透率增加,氧化剂可以均匀地流入PRB。结果表明,最佳填料比例为零价铁(ZVI)/沸石/活性炭(AC)=3:8:10,最佳氧化剂比例为COD/Na2S2O8/H2O2/Fe2=1:5:6:5;Fe2/H2O2/S2O82-的氧化体系具有较高的氧化效率和持久性。沸石的平均再生率为72.71%,AC的平均再生率为68.40%;PRB的渗透率也增加。该技术对我国污染面积较大的垃圾填埋场的修复是有效的,污染物浓度分布不均匀,和长时间的污染。长期吸附和短时间原位氧化的净化模式可应用于长期高浓度有机污染地下水的修复,污染源难以切断的地方。
    Groundwater contamination near landfills is commonly caused by leachate leakage, and permeable reactive barriers (PRBs) are widely used for groundwater remediation. However, the deactivation and blockage of the reactive medium in PRBs limit their long-term effectiveness. In the current study, a new methodology was proposed for the in situ regeneration of PRB to remediate leachate-contaminated groundwater. CO2 coupled with oxidants was applied for the dispersion and regeneration of the fillers; by injecting CO2 to disperse the fillers, the permeability of the PRB was increased and the oxidants could flow evenly into the PRB. The results indicate that the optimum filler proportion was zero-valent iron (ZVI)/zeolites/activated carbon (AC) = 3:8:10 and the optimum oxidant proportion was COD/Na2S2O8/H2O2/Fe2+ = 1:5:6:5; the oxidation system of Fe2+/H2O2/S2O82- has a high oxidation efficiency and persistence. The average regeneration rate of zeolites was 72.71%, and the average regeneration rate of AC was 68.40%; the permeability of PRB also increased. This technology is effective for the remediation of landfills in China that have large contaminated areas, an uneven pollutant concentration distribution, and a long pollution duration. The purification mode of long-term adsorption and short-time in situ oxidation can be applied to the remediation of long-term high-concentration organically polluted groundwater, where pollution sources are difficult to cut off.
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  • 文章类型: Journal Article
    一种选择性去电试剂,具有极高的+2.00(溶液)/+2.41V(固态)与Fc+/0和基于室温稳固的全氟萘(萘基F)自由基阳离子盐的研制和应用。用[NO][F{Al(ORF)3}2]-对商业naph-tha-leneF进行固态去电化,生成[萘基F]*[F{Al(ORF)3}2]-(ORF=OC(CF3)3)。热化学分析揭示了起始[NO]+-试剂的固态去电子电位为+2.34Vvs.带有[F{Al(ORF)3}2]-反离子的Fc+/0,但只有+1.14Vvs.Fc+/0与小[SbF6]-离子。选择性反应证明了[萘基F]*对溶液中多种器官(金属)分子和元素的去电化的选择性:提供并苯的分子结构[四并苯]2,[并五苯]2或二茂铁指示[Fc(CO)]2的碳基复合物的光谱研究,来自白色荧光粉的[P9]+阳离子,无溶剂的铜(I)盐,从铜金属和双阳离子Fe(IV)-蝎子酸配合物[Fe(sc)2]2开始。
    A selective deelectronation reagent with very high potential of +2.00 (solution) / +2.41 V (solid-state) vs. Fc+/0 and based on a room temperature stable perfluoronaphthalene (naphthaleneF) radical cation salt was developed and applied. The solid-state deelectronation of commercial naph-tha-leneF with [NO]+[F{Al(ORF)3}2]- generates [naphthaleneF]+∙[F{Al(ORF)3}2]- (ORF = OC(CF3)3) in gram scale. Thermo-chemical analysis unravels the solid-state de-electronation potential of the starting [NO]+-reagent to be +2.34 V vs. Fc+/0 with [F{Al(ORF)3}2]- counterion, but only +1.14 V vs. Fc+/0 with the small [SbF6]- ion. Selective reactions demonstrate the selectivity of [naphthaleneF]+∙ for deelectronation of a multitude of organ(ometall)ic molecules and elements in solution: providing the molecular struc-tures of the acene dications [tetracene]2+, [pentacene]2+ or spectroscopic evi-dence for the carbo-nyl complex of the ferrocene dication [Fc(CO)]2+, the [P9]+ cation from white phosphor-us, the solvent-free copper(I) salt starting from copper metal and the dicationic Fe(IV)-scorpionate complex [Fe(sc)2]2+.
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  • 文章类型: Journal Article
    枯草芽孢杆菌铁氧还蛋白:NADP氧化还原酶(BsFNR)是硫氧还蛋白还原酶型FNR,其氧化还原特性和与非生理电子受体的反应性几乎没有表征。根据与3-乙酰吡啶腺嘌呤二核苷酸磷酸的氧化还原反应,黄素腺嘌呤二核苷酸(FAD)辅因子的两电子还原中点电位估计为-0.240V。使用5-脱氮黄素单核苷酸(5-脱氮FMN)作为光敏剂的光还原表明,第一和第二单电子转移步骤之间的氧化还原电位差异为0.024V。醌和芳香族N-氧化物对BsFNR的反应性当增加其单电子还原中点氧化还原电位时增加。硝基芳族化合物的反应性较低,由于它们的电子自交换速率较低,但它表现出同样的趋势。混合的单电子和双电子还原反应是醌的特征,而涉及硝基芳烃的反应仅通过单电子还原反应进行。FADH氧化为FAD是完全还原的FAD氧化过程中的限速步骤。与硝基芳烃反应中计算的电子转移距离接近其他FNR,包括植物型酶,因此,尽管它们的结构存在根本差异,但它们对低分子量氧化剂的活性位点可及性相似。
    Bacillus subtilis ferredoxin:NADP+ oxidoreductase (BsFNR) is a thioredoxin reductase-type FNR whose redox properties and reactivity with nonphysiological electron acceptors have been scarcely characterized. On the basis of redox reactions with 3-acetylpyridine adenine dinucleotide phosphate, the two-electron reduction midpoint potential of the flavin adenine dinucleotide (FAD) cofactor was estimated to be -0.240 V. Photoreduction using 5-deazaflavin mononucleotide (5-deazaFMN) as a photosensitizer revealed that the difference in the redox potentials between the first and second single-electron transfer steps was 0.024 V. We examined the mechanisms of the reduction of several different groups of non-physiological electron acceptors catalyzed by BsFNR. The reactivity of quinones and aromatic N-oxides toward BsFNR increased when increasing their single-electron reduction midpoint redox potentials. The reactivity of nitroaromatic compounds was lower due to their lower electron self-exchange rate, but it exhibited the same trend. A mixed single- and two-electron reduction reaction was characteristic of quinones, whereas reactions involving nitroaromatics proceeded exclusively via the one-electron reduction reaction. The oxidation of FADH• to FAD is the rate-limiting step during the oxidation of fully reduced FAD. The calculated electron transfer distances in the reaction with nitroaromatics were close to those of other FNRs including the plant-type enzymes, thus demonstrating their similar active site accessibility to low-molecular-weight oxidants despite the fundamental differences in their structures.
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  • 文章类型: Journal Article
    细胞外基质(ECM)对生物结构至关重要,并决定细胞特性,功能和活动。在许多情况下,它是非常丰富的,胶原蛋白和弹性蛋白是哺乳动物中最丰富的蛋白质。ECM由多种不同的蛋白质种类和糖聚合物组成,与不同的同工型和翻译后修饰(PTM)提供了各种各样的微环境,在决定组织结构和健康中起着关键作用。ECM中存在的许多PTM(例如交联)对完整性和功能至关重要,而其他对ECM结构和相关细胞都有害。据报道,随着年龄的增长,反应性氧化剂和亲电子试剂引起的修饰会在某些ECM中积累。这种积累可以因疾病而加剧,特别是那些与急性或慢性炎症相关的炎症,肥胖和糖尿病。这可能是由于在这些条件下改性剂的通量较高。在这次重点审查中,讨论了氧化剂和其他亲电体对ECM的作用和影响,特别关注动脉壁和动脉粥样硬化性心血管疾病。审查ECM组件上生成的修改,以及这些物种对细胞特性包括粘附的影响,扩散,迁移,生存能力,代谢活动,基因表达和表型。越来越多的数据表明ECM修饰在人类和哺乳动物组织中都很普遍,并且在疾病的发展和进展中起重要作用。
    The extracellular matrix (ECM) is critical to biological architecture and determines cellular properties, function and activity. In many situations it is highly abundant, with collagens and elastin being some of the most abundant proteins in mammals. The ECM comprises of multiple different protein species and sugar polymers, with both different isoforms and post-translational modifications (PTMs) providing a large variety of microenvironments that play a key role in determining tissue structure and health. A number of the PTMs (e.g. cross-links) present in the ECM are critical to integrity and function, whereas others are deleterious to both ECM structure and associated cells. Modifications induced by reactive oxidants and electrophiles have been reported to accumulate in some ECM with increasing age. This accumulation can be exacerbated by disease, and in particular those associated with acute or chronic inflammation, obesity and diabetes. This is likely to be due to higher fluxes of modifying agents in these conditions. In this focused review, the role and effects of oxidants and other electrophiles on ECM are discussed, with a particular focus on the artery wall and atherosclerotic cardiovascular disease. Modifications generated on ECM components are reviewed, together with the effects of these species on cellular properties including adhesion, proliferation, migration, viability, metabolic activity, gene expression and phenotype. Increasing data indicates that ECM modifications are both prevalent in human and mammalian tissues and play an important role in disease development and progression.
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  • 文章类型: Journal Article
    越来越多的证据表明,蔗糖摄入量的增加可能会导致神经系统疾病的发展。认识到定期锻炼有可能减少神经肌肉疾病的发生,本研究调查了运动对下丘脑氧化还原状态的影响,以减轻与高蔗糖摄入相关的不利影响。40只Wistar白化病大鼠接受了高蔗糖饮食,一些团体进行为期3个月的锻炼。发现运动方案可以维持下丘脑的氧化还原平衡。总之,高蔗糖饮食的消耗导致下丘脑的组织学形态紊乱,伴随着caspase-3阳性细胞百分比的增加。此外,高蔗糖饮食破坏了氧化剂/抗氧化剂的比例,有利于氧化剂,导致AOPP和AGEP水平升高。相反,锻炼有效地将这些值中的大多数恢复到接近对照组的水平,表明定期运动对高蔗糖饮食消耗对下丘脑的有害影响具有潜在的保护作用。图形抽象。
    A growing body of evidence suggests that elevated sucrose intake may contribute to the development of neurological disorders. Recognizing that regular exercise has the potential to reduce the occurrence of neuromuscular disorders, the present research investigated the impact of exercise on the redox status of the hypothalamus in mitigating the adverse effects associated with high sucrose intake. Forty Wistar albino rats were subjected to a high sucrose diet, with some groups engaging in exercise for a duration of 3 months. The exercise regimen was found to sustain the redox balance in the hypothalamus. In summary, the consumption of a high sucrose diet resulted in the disturbance of the histological morphology of the hypothalamus, accompanied by an increased percentage of caspase-3 positive cells. Additionally, the high sucrose diet disrupted the oxidant/antioxidant ratio in favor of oxidants, leading to elevated levels of AOPPs and AGEP. Conversely, exercise was effective in restoring most of these values to levels approximating the control group, indicating a potential protective effect of regular exercise against the detrimental impacts of high sucrose dietary consumption on the hypothalamus. Graphical abstract.
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