Ethyl Ethers

乙基醚
  • 文章类型: Journal Article
    本研究介绍了一种创新的针捕集装置(NTD),该装置具有分子印迹聚合物(MIP)表面改性的沸石Y。开发的NTD与气相色谱-火焰离子化检测器(GC-FID)集成在一起,用于分析燃料醚含氧化合物(甲基叔丁基醚,MTBE,乙基叔丁基醚,ETBE,和甲酸叔丁酯,TBF)在尿样中。优化提取温度等关键实验变量,提取时间,盐浓度,和搅拌速度,采用中央复合设计-响应面方法(CCD-RSM)。研究中提取的最佳值为51.2°C提取温度,提取时间46.2min,27%盐浓度,和620rpm的搅拌速度。在优化条件下,校准曲线在0.1-100μgL-1范围内表现出良好的线性,相关系数(R2)超过0.99。MTBE的检测限(LODs),ETBE,和TBF分别获得0.06、0.08和0.09μgL-1。此外,MTBE的定量限(LOQ),ETBE,和TBF分别获得0.18、0.24和0.27μgL-1。还发现富集因子在98-129的范围内。NTD-GC-FID程序显示出高提取效率,使其成为对燃料醚含氧化合物进行尿液生物监测的有希望的工具,与目前的方法相比具有改进的灵敏度和选择性。
    This study introduces an innovative needle trap device (NTD) featuring a molecularly imprinted polymer (MIP) surface-modified Zeolite Y. The developed NTD was integrated with gas chromatography-flame ionization detector (GC-FID) and employed for analysis of fuel ether oxygenates (methyl tert‑butyl ether, MTBE, ethyl tert‑butyl ether, ETBE, and tert‑butyl formate, TBF) in urine samples. To optimize the key experimental variables including extraction temperature, extraction time, salt concentration, and stirring speed, a central composite design-response surface methodology (CCD-RSM) was employed. The optimal values for extraction in the study were found to be 51.2 °C extraction temperature, 46.2 min extraction time, 27 % salt concentration, and 620 rpm stirring speed. Under the optimized conditions, the calibration curves demonstrated excellent linearity within the range of 0.1-100 μg L-1, with correlation coefficients (R2) exceeding 0.99. The limits of detection (LODs) for MTBE, ETBE, and TBF were obtained 0.06, 0.08, and 0.09 μg L-1, respectively. Moreover, the limits of quantification (LOQs) for MTBE, ETBE, and TBF were obtained 0.18, 0.24, and 0.27 μg L-1, respectively. The enrichment factor was also found to be in the range of 98-129.The NTD-GC-FID procedure demonstrated a high extraction efficiency, making it a promising tool for urinary biomonitoring of fuel ether oxygenates with improved sensitivity and selectivity compared to current methods.
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  • 文章类型: Journal Article
    用于核酸(NA)疗法的mRNA的出现开启了许多不同的研究和临床研究领域。然而,与其他NA相比,mRNA的细胞内半衰期较短,可能需要更频繁的给药方案。因为脂质纳米颗粒(LNP)是用于mRNA的主要递送系统,这可能导致与累积的脂质负荷相关的耐受性挑战.这可以通过将酶促裂解的羧酸酯引入脂质组分的疏水区域来解决,特别是,可电离的脂质。然而,酶活性可随年龄显著变化,疾病状态,和物种,可能会限制在人类中的应用。在这里,我们报告了一种依赖于非酶水解的可电离脂质降解的替代方法,导致控制和高效的脂质清除曲线。我们确定了非常有效的例子,并证明了它们在多个临床前物种中的特殊耐受性,包括在非人灵长类动物(NHP)中多次给药。
    The advent of mRNA for nucleic acid (NA) therapeutics has unlocked many diverse areas of research and clinical investigation. However, the shorter intracellular half-life of mRNA compared with other NAs may necessitate more frequent dosing regimens. Because lipid nanoparticles (LNPs) are the principal delivery system used for mRNA, this could lead to tolerability challenges associated with an accumulated lipid burden. This can be addressed by introducing enzymatically cleaved carboxylic esters into the hydrophobic domains of lipid components, notably, the ionizable lipid. However, enzymatic activity can vary significantly with age, disease state, and species, potentially limiting the application in humans. Here we report an alternative approach to ionizable lipid degradability that relies on nonenzymatic hydrolysis, leading to a controlled and highly efficient lipid clearance profile. We identify highly potent examples and demonstrate their exceptional tolerability in multiple preclinical species, including multidosing in nonhuman primates (NHP).
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  • 文章类型: Journal Article
    总可氧化前体(TOP)测定已广泛用于检测不具有分析标准的PFAS污染物。它使用来自过硫酸盐在碱性pH值下的热活化的羟基自由基(HO•)将含H的前体转化为全氟烷基羧酸盐(PFCA)进行目标分析。然而,当前的TOP测定氧化方法不适用于新兴的PFAS,因为(i)许多结构不含有用于HO•攻击的C-H键,以及(ii)转化产物不一定是PFCA。在这项研究中,我们探索了使用经典的酸性过硫酸盐消化,产生硫酸根(SO4-•),以扩展TOP测定的能力。我们检查了含有C-H或-COO-的Nafion相关醚磺酸盐的氧化,表征氧化产物,并量化了F原子平衡。SO4-·氧化极大地扩展了可氧化前体的范围。转化是通过脱羧开始的,随后是各种自发的步骤,如HF消除和酯水解。我们进一步比较了使用SO4-·与HO·的传统氟调聚物的氧化。结果表明新的产品分布模式,取决于官能团和氧化剂剂量。一般趋势和策略也通过分析100000或10000倍稀释的水性成膜泡沫(含有各种氟调聚物表面活性剂和有机物)和掺加的Nafion前体的混合物来验证。因此,(1)SO4-•和HO•氧化的联合使用,(2)扩大标准化学品清单,和(3)SO4-·氧化机制的进一步阐明将为探测新出现的PFAS污染物提供更关键的信息。
    The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO•) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO• attack and (ii) the transformation products are not necessarily PFCAs. In this study, we explored the use of classic acidic persulfate digestion, which generates sulfate radicals (SO4-•), to extend the capability of the TOP assay. We examined the oxidation of Nafion-related ether sulfonates that contain C-H or -COO-, characterized the oxidation products, and quantified the F atom balance. The SO4-• oxidation greatly expanded the scope of oxidizable precursors. The transformation was initiated by decarboxylation, followed by various spontaneous steps, such as HF elimination and ester hydrolysis. We further compared the oxidation of legacy fluorotelomers using SO4-• versus HO•. The results suggest novel product distribution patterns, depending on the functional group and oxidant dose. The general trends and strategies were also validated by analyzing a mixture of 100000- or 10000-fold diluted aqueous film-forming foam (containing various fluorotelomer surfactants and organics) and a spiked Nafion precursor. Therefore, (1) the combined use of SO4-• and HO• oxidation, (2) the expanded list of standard chemicals, and (3) further elucidation of SO4-• oxidation mechanisms will provide more critical information to probe emerging PFAS pollutants.
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  • 文章类型: Journal Article
    这项研究调查了尖端的合成化学方法,用于设计和生产具有改善疗效和减少不良反应的创新抗疟药物。合成了新的氨基(-NH2)和羟基(-OH)官能化的11-氮杂的话9、12和14及其衍生物11a,13a-e,和15a-b通过ART,并通过肌内(i.m.)和口服途径在瑞士小鼠中测试了其针对约氏疟原虫的AMA(抗疟活性)。醚衍生物13c是通过i.m.途径最具活性的化合物,它在12mg/kg×4天的剂量下显示出100%的保护作用,在6mg/kg的剂量下在第4天显示出100%的寄生虫血症清除率。胺11a,醚衍生物13d,13e和醚15a也显示有希望的抗疟活性。β-Arteether通过口服途径在48mg/kg×4天的剂量下产生100%的保护作用,在24mg/kg×4天的剂量下产生20%的保护作用。虽然它在6mg/kg×4天显示100%的保护,在3mg/kg×4天没有保护。
    This study investigates cutting-edge synthetic chemistry approaches for designing and producing innovative antimalarial drugs with improved efficacy and fewer adverse effects. Novel amino (-NH2) and hydroxy (-OH) functionalized 11-azaartemisinins 9, 12, and 14 were synthesized along with their derivatives 11a, 13a-e, and 15a-b through ART and were tested for their AMA (antimalarial activity) against Plasmodium yoelii via intramuscular (i.m.) and oral routes in Swiss mice. Ether derivative 13c was the most active compound by i.m. route, it has shown 100 % protection at the dose of 12 mg/kg × 4 days and showed 100 % clearance of parasitaemia on day 4 at dose of 6 mg/kg. Amine 11a, ether derivatives 13d, 13e and ether 15a also showed promising antimalarial activity. β-Arteether gave 100 % protection at the dose of 48 mg/kg × 4 days and 20 % protection at 24 mg/kg × 4 days dose by oral route, while it showed 100 % protection at 6 mg/kg × 4 days and no protection at 3 mg/kg × 4 days by i.m. route.
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  • 文章类型: Journal Article
    全氟烷基醚羧酸(PFECA)已成为传统的全氟和多氟烷基物质(PFAS)的新型替代品。现有的研究已经揭示了各种PFAS诱导的肝毒性,包括PFECA。然而,这些研究主要集中在整个肝脏组织的整体变化,特别是在肝细胞中,与PFAS对不同肝脏非实质细胞(NPC)的影响仍未充分了解。在本研究中,我们检查了暴露于全氟-3,5,7,9,11-五氧杂萘癸酸(PFO5DoDA)后肝NPC的异质性反应,一种PFECA,通过向雄性小鼠施用PFO5DoDA(5μg/L)污染的水一年。来自肝脏的15008个细胞的单细胞RNA测序(scRNA-seq)鉴定了10个不同的NPC群体。值得注意的是,尽管暴露于5μg/LPFO5DoDA后,相对肝脏重量基本保持不变,观察到增殖细胞的增加,表明增殖的NPC可能导致暴露于PFAS的肝脏中常见的肝肿大。肝NPC的组成也有相当大的变化。具体来说,B细胞总数大幅下降,而许多其他细胞,如单核细胞和巨噬细胞,PFO5DoDA暴露后增加。此外,PFO5DoDA暴露后,肝NPC种群之间的相互作用发生了不同的变化。研究结果强调了肝脏NPC对PFO5DoDA暴露反应的异质性。一起来看,免疫细胞群及其细胞间相互作用的变化表明,PFO5DoDA破坏了肝脏的免疫稳态.这些发现为PFAS诱导的肝损伤的细胞机制提供了新的见解。
    Perfluoroalkyl ether carboxylic acids (PFECA) have emerged as novel alternatives to legacy per- and polyfluoroalkyl substances (PFAS). Existing research has revealed hepatoxicity induced by various PFAS, including PFECA. However, these studies have primarily focused on overall changes in whole liver tissue, particularly in hepatocytes, with the impact of PFAS on diverse liver non-parenchymal cells (NPCs) still inadequately understood. In the present study, we examined the heterogeneous responses of hepatic NPCs following exposure to perfluoro-3,5,7,9,11-pentaoxadodecanoic acid (PFO5DoDA), a type of PFECA, by administering PFO5DoDA (5 μg/L)-contaminated water to male mice for one year. Single-cell RNA sequencing (scRNA-seq) of 15 008 cells from the liver identified 10 distinct NPC populations. Notably, although relative liver weight remained largely unchanged following exposure to 5 μg/L PFO5DoDA, there was an observed increase in proliferating cells, indicating that proliferating NPCs may contribute to the hepatomegaly frequently noted in PFAS-exposed livers. There was also a considerable alteration in the composition of hepatic NPCs. Specifically, the total number of B cells decreased substantially, while many other cells, such as monocytes and macrophages, increased after PFO5DoDA exposure. In addition, interactions among the hepatic NPC populations changed variously after PFO5DoDA exposure. The findings emphasize the heterogeneity in the responses of hepatic NPCs to PFO5DoDA exposure. Taken together, the changes in immune cell populations and their intercellular interactions suggest that PFO5DoDA disrupts immune homeostasis in the liver. These findings offer new insights into the cellular mechanisms of PFAS-induced liver damage.
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  • 文章类型: Journal Article
    暂无摘要。
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  • 文章类型: Journal Article
    天然产物的结构修饰是提高抗真菌活性的有效途径,因此,被广泛用于新的农用化学产品的开发。在这项工作中,设计了一系列含有肟醚结构的新型香豆素衍生物,合成,并评估抗真菌活性。一些设计的化合物对测试的真菌表现出有希望的抗真菌活性,和化合物4a,4c,5a,和6b的EC50值相当于商业杀真菌剂的EC50值。化合物6b是针对枯萎病丝核菌的最有希望的候选杀真菌剂(EC50=0.46μg/mL)。体内抗真菌生物测定表明化合物5a和6b可以用作新型农业抗真菌剂。此外,显微镜显示,化合物6b诱导菌丝的蔓延生长,扭曲了细胞壁的轮廓,线粒体数量减少。此外,取代基空间的影响,静电,疏水,使用准确可靠的三维定量结构-活性关系(3D-QSAR)模型阐明了氢键场。此处介绍的结果将指导发现用于农业中植物病害控制的潜在新型杀菌剂。
    Structural modification of natural products is an effective approach for improving antifungal activity and has, therefore, been used extensively in the development of new agrochemical products. In this work, a series of novel coumarin derivatives containing oxime ether structures were designed, synthesized, and evaluated for antifungal activity. Some of the designed compounds exhibited promising antifungal activities against tested fungi, and compounds 4a, 4c, 5a, and 6b had EC50 values equivalent to those of commercial fungicides. Compound 6b was the most promising candidate fungicide against Rhizoctonia solani (EC50 = 0.46 μg/mL). In vivo antifungal bioassays suggested that compounds 5a and 6b could serve as novel agricultural antifungals. Furthermore, microscopy demonstrated that compound 6b induced the sprawling growth of hyphae, distorted the outline of cell walls, and reduced mitochondrial numbers. Additionally, the effects of the substituent steric, electrostatic, hydrophobic, and hydrogen-bond fields were elucidated using an accurate and reliable three-dimensional quantitative structure-activity relationship (3D-QSAR) model. The results presented here will guide the discovery of potential novel fungicides for plant disease control in agriculture.
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  • 文章类型: Journal Article
    背景:在反刍动物中,纤维饲料必须包括在口粮中,以确保正常的瘤胃生理和防止瘤胃相关代谢疾病的发生。除了是纤维饲料的来源,它们含有取决于消化水平和蛋白质的能量,矿物,脂肪酸,矿物,和次要化合物。
    目的:本研究旨在确定营养物质,脂肪酸,pennyroyal(MenthapulegiumL.)植物的矿物质和体外瘤胃发酵值。
    方法:在不同的物候阶段收集pennyroyal植物样品(营养,充分开花,和种子膨胀)来自天然草地。分析了样品的核心营养素,缩合单宁,矿物,脂肪酸,和体外瘤胃发酵参数。
    结果:钙(Ca)和铁(Fe)含量以及体外瘤胃发酵参数(总产气和甲烷产量,有机物消化(OMd),氨氮)随物候阶段的增加而降低(p<0.05)。亚油酸的百分比,α-亚麻酸,pennyroyal植物的ω-3,ω-6和多不饱和脂肪酸(PUFA)随着物候阶段线性增加(p<0.05)。然而,盛花期体外瘤胃发酵液中丁酸(BA)浓度低于其他阶段(p<0.05)。
    结论:Pennyroyal植物在高值的醚提取物(EE)方面是一种功能性植物,α-亚麻酸,亚油酸,∑ω-3脂肪酸,Ca,Fe和Zn含量。这种植物用作动物饲料,当它的Ca值最高的阶段,Mg,S和Zn矿物质和离体OMd是营养性和全花期。作为∑ω-3和∑ω-6脂肪酸和核心营养素(CP和EE)的动物饲料具有良好潜力的阶段是种子膨胀阶段。
    In ruminants, fibrous feedstuffs must be included in the ration to ensure normal rumen physiology and to prevent the occurrence of rumen-related metabolic diseases. In addition to being a source of fibrous feedstuffs, they contain energy depending on the level of digestion and protein, minerals, fatty acids, minerals, and secondary compounds.
    This study aimed to determine the nutrient matter, fatty acid, mineral and in vitro rumen fermentation values of the pennyroyal (Mentha pulegium L.) plant.
    The pennyroyal plant samples were collected at different phenological stages (vegetative, full flowering, and seed bulking) from the natural meadow. The samples were analysed for core nutrients, condensed tannins, minerals, fatty acids, and in vitro ruminal fermentation parameters.
    The calcium (Ca) and iron (Fe) contents and in vitro ruminal fermentation parameters (total gas production and methane production, organic matter digestion (OMd), and the ammonia-nitrogen) decreased with increasing phenological stage (p < 0.05). The percentages of linoleic, α-linolenic, ω-3, ω-6 and polyunsaturated fatty (PUFA) acids of the pennyroyal plant linearly increased with the phenological stages (p < 0.05). However, butyric acid (BA) concentration in the in vitro ruminal fermentation fluid in the full flowering stage was lower than that of other stages (p < 0.05).
    Pennyroyal plant is a functional plant in terms of high values of ether extract (EE), α-linolenic acid, linoleic acid, ∑ω-3 fatty acids, Ca, Fe and Zn contents. For this plant to be used as animal feed, the stage when it has the highest values for Ca, Mg, S and Zn minerals and in vitro OMd were vegetative and full flowering. The stage with good potential as animal feed for ∑ω-3 and ∑ω-6 fatty acids and core nutrients (CP and EE) is the seed bulking stage.
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  • 文章类型: Journal Article
    四溴双酚A双(2-羟乙基)醚(TBBPA-DHEE),作为四溴双酚A的主要衍生物之一,因其健康风险而备受关注。在这项研究中,神经毒性,机制,系统研究了TBBPA-DHEE对性发育雄性大鼠的敏感性。神经行为研究表明,TBBPA-DHEE暴露可以显著影响行为,学习,和雄性大鼠的记忆能力,加重他们的抑郁.TBBPA-DHEE暴露可抑制神经递质的分泌。转录组学研究表明,TBBPA-DHEE可以显著影响基因表达,共富集334个差异表达基因。GO功能富集分析表明,TBBPA-DHEE暴露可显著影响突触和细胞组分相关基因的表达。KEGG功能富集分析表明,TBBPA-DHEE暴露可显著影响神经相关信号通路的表达,神经发育,和信号转导。易感性分析表明,雌性大鼠比雄性大鼠更容易暴露于TBBPA-DHEE。因此,TBBPA-DHEE暴露对雄性发育大鼠具有神经发育毒性,雌性发育大鼠比雄性发育大鼠更易感。其可能的分子机制是TBBPA-DHEE可抑制神经递质的分泌,影响与神经发育和信号转导相关的信号通路。
    Tetrabromobisphenol A bis (2- hydroxyethyl) ether (TBBPA-DHEE), as one of the main derivatives of Tetrabromobisphenol A, been attracted attention for its health risks. In this study, the neurotoxicity, mechanism, and susceptivity of TBBPA-DHEE exposure to sexually developing male rats were systematically studied. Neurobehavioral research showed that TBBPA-DHEE exposure could significantly affect the behavior, learning,and memory abilities of male-developing rats, and aggravate their depression. TBBPA-DHEE exposure could inhibit the secretion of neurotransmitters. Transcriptomics studies show that TBBPA-DHEE can significantly affect gene expression, and a total of 334 differentially expressed genes are enriched. GO function enrichment analysis shows that TBBPA-DHEE exposure can significantly affect the expression of genes related to synapses and cell components. KEGG function enrichment analysis shows that TBBPA-DHEE exposure can significantly affect the expression of signal pathways related to nerves, nerve development, and signal transduction. Susceptibility analysis showed that female rats were more susceptible to TBBPA-DHEE exposure than male rats. Therefore, TBBPA-DHEE exposure has neurodevelopmental toxicity to male developmental rats, and female developmental rats are more susceptible than male developmental rats. Its possible molecular mechanism is that TBBPA-DHEE may inhibit the secretion of neurotransmitters and affect signal pathways related to neurodevelopment and signal transduction.
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  • 文章类型: Journal Article
    来自木质素降解农杆菌的LigE型β-醚酶。已经被确认,这有助于聚合木质素的降解。对木质素二聚体模型化合物的测试显示,它不催化先前报道的鞘氨醇SYK-6LigE的反应,而是显示出β-5苯基香豆素木质素二聚体的活性。反应产物不含谷胱甘肽,表明还原型谷胱甘肽在该酶中具有催化作用。确定了三种反应产物:主要产物是由涉及甲醛损失的C-C片段产生的顺式-二苯乙烯;两种次要产物是消除谷胱甘肽产生的烯烃,和一种氧化酮,提议由中间体与分子氧的反应产生。对苏打木质素的重组酶的测试通过二维NMR分析揭示了新信号的形成。其化学位移与聚合物木质素中的二苯乙烯单元的形成一致。
    A LigE-type beta-etherase enzyme from lignin-degrading Agrobacterium sp. has been identified, which assists degradation of polymeric lignins. Testing against lignin dimer model compounds revealed that it does not catalyse the previously reported reaction of Sphingobium SYK-6 LigE, but instead shows activity for a β-5 phenylcoumaran lignin dimer. The reaction products did not contain glutathione, indicating a catalytic role for reduced glutathione in this enzyme. Three reaction products were identified: the major product was a cis-stilbene arising from C-C fragmentation involving loss of formaldehyde; two minor products were an alkene arising from elimination of glutathione, and an oxidised ketone, proposed to arise from reaction of an intermediate with molecular oxygen. Testing of the recombinant enzyme against a soda lignin revealed the formation of new signals by two-dimensional NMR analysis, whose chemical shifts are consistent with the formation of a stilbene unit in polymeric lignin.
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