Lepidium

Lepidium
  • 文章类型: Journal Article
    在冷冻有机溶剂和蛋白质环境中,对叶绿素a的光激发三重态进行了磁光选择(MPS)研究,由Virginicum的水溶性叶绿素蛋白(WSCP)提供,据报道。MPS实验将通过线性偏振光激发实现的光选择与电子顺磁共振(EPR)光谱的磁选择相结合,允许确定两种环境中光学跃迁偶极矩和零场分裂张量轴的相对方向。我们证明了所提出的方法的鲁棒性,用于定量描述颜料之间的激子相互作用。通过WSCP中的EPR分析确定的光学跃迁偶极矩的方向,被确定为适当的模型系统,与点偶极近似中计算的结果非常吻合。此外,MPS提供有关三重态电子特性的信息,定位于蛋白质簇的单个叶绿素a色素上,就分子框架中零场分裂张量轴的方向而言。
    A magnetophotoselection (MPS) investigation of the photoexcited triplet state of chlorophyll a both in a frozen organic solvent and in a protein environment, provided by the water-soluble chlorophyll protein (WSCP) of Lepidium virginicum, is reported. The MPS experiment combines the photoselection achieved by exciting with linearly polarized light with the magnetic selection of electron paramagnetic resonance (EPR) spectroscopy, allowing the determination of the relative orientation of the optical transition dipole moment and the zero-field splitting tensor axes in both environments. We demonstrate the robustness of the proposed methodology for a quantitative description of the excitonic interactions among pigments. The orientation of the optical transition dipole moments determined by the EPR analysis in WSCP, identified as an appropriate model system, are in excellent agreement with those calculated in the point-dipole approximation. In addition, MPS provides information on the electronic properties of the triplet state, localized on a single chlorophyll a pigment of the protein cluster, in terms of orientation of the zero-field splitting tensor axes in the molecular frame.
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  • 文章类型: Journal Article
    Matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) is a novel technique for in-situ distribution of various substances in tissue without labeling. This technique is increasingly applied to the study of medicinal plants owing to its high spatial resolution and its potential of in-situ analysis in small molecules. In this study, the structural information and their fragmentation patterns of the midazole alkaloids(1,3-dibenzyl-4,5-dimethylimidazolium chloride and 1,3-dibenzyl-2,4,5-trimethylimi-dazolium chloride) and benzylglucosinolate in the medicinal plant Maca(Lepdium meyeni) root were analyzed by ultra-high-performance liquid phase combined with LTQ-Orbitrap mass spectrometry(UHPLC-HR-MS). The localization of these active ingredients in the cross-sections of Maca root was performed by MALDI-MSI. These results demonstrated that the two types of imidazole alkaloids had a similar distributed pattern. They were located more in the cortex and the periderm than those in the medulla of a lateral root, while the localization of benzylglucosinolate was concentrated in the center of the root rather than in the cortex and the periderm. The precise spatial distribution of various secondary metabolites in tissue provides an important scientific basis for the accumulation of medicinal plant active ingredients in tissues. In addition, this imaging method is a promising technique for the rapid evaluation and identification of the active ingredients of traditional Chinese medicine in plant tissues, as well as assisting the research on the processing of medicinal plants.
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  • 文章类型: Journal Article
    BACKGROUND: The consumption of botanical dietary supplements (BDS) is a common practice among the US population. However, the potential for botanical-drug interactions exists, and their mechanisms have not been thoroughly studied. CYP3A4 is an important enzyme that contributes to the metabolism of about 60% of clinically used drugs.
    OBJECTIVE: To investigate the potential for botanical-drug interactions of Lepidium meyenii Walpers (maca) root and Euterpe oleracea Mart. (açaí) berries, two commonly used BDS, when co-administered with CYP3A4-metabolized drugs.
    METHODS: In an attempt to decrease the general discrepancy between in vivo and in vitro studies, the absorption profiles, particularly for passive diffusion, of plant extracts were investigated. Specifically, the parallel artificial membrane permeability assay (PAMPA) model was utilized to simulate intestinal filtration of passively diffused constituents of açaí and maca extracts. These were subsequently screened for in vitro liver CYP3A4 inhibition and induction. In the inhibition assay, midazolam was used as the probe substrate on genotyped human liver microsomes (CYP3A5 null), and the production of its 1\'-substituted metabolite when co-cultured with extract treatments was monitored. In the induction assay, extract treatments were applied to human primary hepatocytes, and quantitative PCR analysis was performed to determine CYP3A4 mRNA expression.
    RESULTS: Passively diffused constituents of the methanol açaí extract (IC50 of 28.03 µg/µl) demonstrated the highest inhibition potential, and, at 1.5 µg/µl, induced significant changes in CYP3A4 gene expression. The composition of this extract was further investigated using the chemometric tool Mass Profiler Professional (MPP) on liquid chromatography-mass spectroscopy (LC-MS) data. Subsequently, five compounds of interest characterized by high abundance or high permeability were extracted for further study. This included efforts in effective passive permeability determination and structural elucidation by tandem mass spectrometry (MS/MS).
    CONCLUSIONS: The passively absorbable portion of a methanol açaí extract exhibited inhibition and induction effects on CYP3A4 suggesting the potential to produce botanical-drug interactions.
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  • 文章类型: Journal Article
    背景:在发达国家广泛使用自制和民间疗法,使用的材料是植物提取物,柠檬汁和一些干燥的昆虫尸体。
    方法:我们报告了一例严重眼外伤的病例,该病例是在一名47岁男子的双眼中自行施用植物种子后,他将植物LepidiumSativum(Rashad)的种子放入眼睛后,双侧出现严重的眼部损伤。他报告了严重的眼部疼痛和红肿,结膜上皮缺损和睑粘连。进行了结膜活检,结果对眼部瘢痕性天疱疮(OCP)的免疫染色研究呈阴性。患者视力由治疗前的20/40提高至治疗后的20/25,随访3个月无后遗症。
    结论:自诱导植物提取物可引起眼部并发症。公众意识对于阻止在人眼中使用这些有害植物提取物是必要的。
    BACKGROUND: Homemade and folk remedies\' use is widely practiced in under developed countries, of the used materials are plant extracts, lemon juice and some dried insect bodies.
    METHODS: We report a case of severe ocular injury and its management after self administered plants seeds in both the eyes of a 47-year-old man who had bilateral severe ocular damage after he put the seeds of a plant Lepidium Sativum (Rashad) in his eyes. He reported severe ocular pain and redness, conjunctival epithelial defect and symblepharon. A conjunctival biopsy was taken which turned out to be negative for the immunological staining studies for Ocular Cicatricial Pemphegoid (OCP). The patient\'s visual acuity improved from 20/40 before treatment to 20/25 after treatment with no further sequelae after 3 months follow-up.
    CONCLUSIONS: Self induced plant extracts can cause ocular complications. Public awareness is necessary to help in discouraging the use of these harmful plant extracts in human eyes.
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  • 文章类型: Case Reports
    A young female with prolonged intermenstrual bleeding was found to have raised total plasma testosterone of 25.8 nmol/l (NR<2.9 nmol/l) using the Roche Elecsys Testosterone I immunoassay without clinical features of virulisation. Few months ago investigations for lethargy and low libido had shown normal total testosterone of 0.8 nmol/l. Further history revealed that she was using maca extract to improve her lethargy and low libido. Maca is traditionally used for its aphrodisiac and fertility-enhancing properties. Maca use has not been shown to affect serum testosterone in mice and human studies. Immunoassay interference with maca was suspected. Testosterone immunoassays use monoclonal antibodies specifically directed against testosterone. They are prone to interference from androgenic compounds. Reanalysis of the original serum sample using Elecsys Testosterone II assay, a higher affinity assay, revealed a total testosterone level of 2.9 nmol/l. It is important to exclude assay interference when testosterone level is greater than 5 nmol/l without supportive clinical signs.
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