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Carla Kirschbaum Essa M. Saied Kim Greis Eike Mucha Sandy Gewinner Wieland Schllkopf Gerard Meijer Gert von Helden Berwyck L. J. Poad Stephen J. Blanksby Christoph Arenz Kevin Pagel 《Angewandte Chemie (International ed. in English)》2020,59(32):13638-13642
1‐Deoxysphingolipids are a recently described class of sphingolipids that have been shown to be associated with several disease states including diabetic and hereditary neuropathy. The identification and characterization of 1‐deoxysphingolipids and their metabolites is therefore highly important. However, exact structure determination requires a combination of sophisticated analytical techniques due to the presence of various isomers, such as ketone/alkenol isomers, carbon–carbon double‐bond (C=C) isomers and hydroxylation regioisomers. Here we demonstrate that cryogenic gas‐phase infrared (IR) spectroscopy of ionized 1‐deoxysphingolipids enables the identification and differentiation of isomers by their unique spectroscopic fingerprints. In particular, C=C bond positions and stereochemical configurations can be distinguished by specific interactions between the charged amine and the double bond. The results demonstrate the power of gas‐phase IR spectroscopy to overcome the challenge of isomer resolution in conventional mass spectrometry and pave the way for deeper analysis of the lipidome. 相似文献
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IntroductionThemotionoftheinviscid,irrotationalandincompressiblefluidinacylindricalcontainerwithradiusaisgovernedbyFig.1Sloshofaliquidinacylindricalcontainer2=0 (inV),(1)r=0 (onr=a),(2)z=0 (onz=-h),(3)ηt+·η=z (onz=η),(4)t+12|… 相似文献
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Miji Yeom Hyanggi Ji Jongheon Shin Eunae Cho De-Hun Ryu Deokhoon Park Eunsun Jung 《Molecules (Basel, Switzerland)》2022,27(4)
Striae distensae (SD) or stretch marks are common linear scars of atrophic skin with disintegrating extracellular matrix (ECM) structures. Although fibroblasts contribute to the construction of ECM structure in SD, some studies have reported that mast cell degranulation causes the disruption of ECM in early SD lesions. Lagerstroemia indica flower (LIF) has traditionally been used in India as a diuretic. However, little is known about the effect and molecular action of Lagerstroemia indica flower extract (LIFE) on alleviating SD. This study evaluated the effects of LIFE on mast cell degranulation and the synthesis of ECM components in fibroblasts. LIFE inhibits the adhesion of rat basophilic leukemia (RBL) cells, RBL-2H3 on fibronectin (FN) and the expression of integrin, a receptor for FN, thereby reducing focal adhesion kinase (FAK) phosphorylation. In addition, LIFE attenuated the allergen-induced granules and cytokine interleukin 3 (IL-3) through the adhesion with FN. Moreover, the conditioned medium (CM) of activated mast cells decreases the synthesis of ECM components, and LIFE restores the abnormal expressions induced by activated mast cells. These results demonstrate that LIFE suppresses FN-induced mast cell activation and promotes the synthesis of ECM components in fibroblast, which indicates that LIFE may be a useful cosmetic agent for SD treatment. 相似文献
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Jacek Lipok Tomasz Cierpicki Paweł Kafarski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1657-1660
Alternaria sp. isolated from the surface of carrot ( Daucus carota ) seeds appeared to be able to degrade amino-(4-methoxyphenyl)-methanephosphonic acid using it as a sole source of carbon, nitrogen, and phosphorus for growth. 相似文献
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The present study illustrated the stability of linkage isomers of [Fe(CO)4(NCS)]? and [Fe(CO)4(SCN)]? by the use of PBE quantum method. It also investigated the polarity of solvent effect on dipole moment, structural parameters, and frontier orbital energies of complexes. The results indicated that the polarity of solvent had a significant effect on the frontier orbital energies and HOMO-LUMO gap. The character of Fe-C bonds of molecules was analyzed by Natural bond orbital (NBO) analysis. Back-bonding effect in these bonds was explored with calculation of quadrupole polarization of carbon atom by QTAIM analysis. Also, 14N NQR parameters were used for the illustration of Fe-NCS and Fe-SCN bonds. 相似文献
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团簇结构测量是团簇科学研究中的一个重要课题。文章对近几年发展的注入离子漂移管技术进行了详细介绍与分析,该技术是上前测量团簇结构近似程度最高的技术,已在C,Si,Ge及Al等原子团簇的结构研究中获得广泛应用,并取得了许多重要结果。 相似文献