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11.
Ariana Borges Souza Monique Rodrigues Moreira Carly Henrique Gambeta Borges Marília Rodrigues Simão Jairo Kenupp Bastos João Paulo Barreto de Sousa Sérgio Ricardo Ambrosio Rodrigo Cassio Sola Veneziani 《Biomedical chromatography : BMC》2013,27(3):280-283
The Copaifera species (Leguminoseae) are popularly known as ‘copaíba’ or ‘copaíva’ and are grown in the states of Amazonas, Pará and Ceará in northern Brazil. The oleoresins obtained from these species have been extensively used owing to their pharmacological potential and their application in cosmetic and pharmaceutical preparations. In the present study, the development and validation of a novel, rapid and efficient RP‐HPLC methodology for the analysis of the diterpene (?)‐copalic acid (CA), pointed out as the only chemical marker of the Copaifera genus, are described. The regression equation (Y = 26,707x ? 29,498) was obtained with good linearity (r2 = 0.9993) and the limits of quantification and detection were 9.182 and 3.032 µg/mL, respectively. The precision and the accuracy of the method were adequate (lower than 4%). Finally, the validation parameters evaluated were satisfactorily met, so the developed method represents a suitable tool for application in the quality control of such natural products. Further studies aiming to develop analytical methodologies for each Copaifera species using a more representative number of chemical markers should be performed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
12.
Cephalotanins A–D,Four Norditerpenoids Represent Three Highly Rigid Carbon Skeletons from Cephalotaxus sinensis
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Dr. Jin‐Biao Xu Dr. Yao‐Yue Fan Prof. Dr. Li‐She Gan Dr. Yu‐Bo Zhou Prof. Dr. Jia Li Prof. Dr. Jian‐Min Yue 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14648-14654
Four polycyclic norditerpenoids, cephalotanins A–D ( 1 – 4 ) representing three unprecedented carbon skeletons with highly rigid ring systems, were isolated from Cephalotaxus sinensis and structurally characterized by a combination of various methods. Compounds 1 and 2 are new skeletal norditerpenoid trilactones, while 3 and 4 are two norditerpenoids featuring different new carbon skeletons. Biosynthetic pathways for 1 – 4 were proposed by involving diverse and very fascinating chemical events with the coexisting cephalotane troponoids as the precursors. Compound 1 exhibited good NF‐κB inhibition with an IC50 value of 4.12±0.61 μΜ. 相似文献
13.
油楠树脂油化学成分的研究 总被引:2,自引:0,他引:2
采用毛细管气相色谱-质谱(CGC-MS)联用技术对油楠树脂油的化学成分进行研究,共分离出42个峰,并确认了其中39种成分,占总油量的94.31%。分离出的主要成分为蓖麻油酸(17.91%);7,7,8,8-四甲基二环[4.2.0]辛烷-1(6),3-二烯-2,5-二酮(7.60%);1,2-二乙基-3,4-二甲基-苯(6.70%);1,2,6,6-四甲基-1,3-环己二烯(5.35%);n-棕榈酸(4.47%);1,3,4-三甲基-3-环己烯-1-甲醛(4.17%)。 相似文献
14.
Izabela Gregorczyk Agnieszka Jasiecka-Mikoajczyk Tomasz Malanka 《Molecules (Basel, Switzerland)》2021,26(11)
The main purpose of this study was to investigate whether the blockade of the interaction between the receptor activator of nuclear factor-κB (NF-ĸB) ligand (RANKL) and its receptor RANK as well as the blockade of NF-κB inhibitor kinase (IKK) and of NF-κB translocation have the potential to suppress the pathogenesis of allergic asthma by inhibition and/or enhancement of the production by CD4+ and CD8+ T cells of important cytokines promoting (i.e., IL-4 and IL-17) and/or inhibiting (i.e., IL-10 and TGF-β), respectively, the development of allergic asthma. Studies using ovalbumin(OVA)-immunized mice have demonstrated that all the tested therapeutic strategies prevented the OVA-induced increase in the absolute number of IL-4- and IL-17-producing CD4+ T cells (i.e., Th2 and Th17 cells, respectively) indirectly, i.e., through the inhibition of the clonal expansion of these cells in the mediastinal lymph nodes. Additionally, the blockade of NF-κB translocation and RANKL/RANK interaction, but not IKK, prevented the OVA-induced increase in the percentage of IL-4-, IL-10- and IL-17-producing CD4+ T cells. These latter results strongly suggest that both therapeutic strategies can directly decrease IL-4 and IL-17 production by Th2 and Th17 cells, respectively. This action may constitute an important mechanism underlying the anti-asthmatic effect induced by the blockade of NF-κB translocation and of RANKL/RANK interaction. Thus, in this context, both these therapeutic strategies seem to have an advantage over the blockade of IKK. None of the tested therapeutic strategies increased both the absolute number and frequency of IL-10- and TGF-β-producing Treg cells, and hence they lacked the potential to inhibit the development of the disease via this mechanism. 相似文献
15.
Valeria Guarrasi Giacoma Cinzia Rappa Maria Assunta Costa Fabio Librizzi Marco Raimondo Vita Di Stefano Maria Antonietta German Silvia Vilasi 《Molecules (Basel, Switzerland)》2021,26(8)
Waste valorization represents one of the main social challenges when promoting a circular economy and environmental sustainability. Here, we evaluated the effect of the polyphenols extracted from apple peels, normally disposed of as waste, on the amyloid aggregation process of κ-casein from bovine milk, a well-used amyloidogenic model system. The effect of the apple peel extract on protein aggregation was examined using a thioflavin T fluorescence assay, Congo red binding assay, circular dichroism, light scattering, and atomic force microscopy. We found that the phenolic extract from the peel of apples of the cultivar “Fuji”, cultivated in Sicily (Caltavuturo, Italy), inhibited κ-casein fibril formation in a dose-dependent way. In particular, we found that the extract significantly reduced the protein aggregation rate and inhibited the secondary structure reorganization that accompanies κ-casein amyloid formation. Protein-aggregated species resulting from the incubation of κ-casein in the presence of polyphenols under amyloid aggregation conditions were reduced in number and different in morphology. 相似文献
16.
Using a master equation for the reduced density matrix of open quantum system, the influence of coordinate-dependent microscopical diffusion coefficients on the decay rate from a potential well is studied. For different temperatures, frictions, heights of barrier and ratios of stiffnesses of the potential in the minimum and on the top of the barrier, the quasistationary decay rates are obtained with the sets of coordinate-dependent and -independent microscopical diffusion coefficients, and coordinate-dependent phenomenological diffusion coefficients. 相似文献
17.
Ginseng is a vastly used herbal supplement in Southeast Asian countries. Red ginseng extract enriched with Rg3 (Rg3-RGE) is a formula that has been extensively studied owing to its various biological properties. Persicaria tinctoria (PT), belonging to the Polygonaceae family, has also been reported for its anti-inflammatory properties. Ulcerative colitis (UC) is inflammation of the large intestine, particularly in the colon. This disease is increasingly common and has high probability of relapse. We investigated, separately and in combination, the effects of Rg3-RGE and PT using murine exemplary of UC induced by DSS (Dextran Sulfate Sodium). For in vitro and in vivo experiments, nitric oxide assay, qRT-Polymerase Chain Reaction (PCR), Western blot, ulcerative colitis introduced by DSS, Enzyme Linked Immunosorbent Assay (ELISA), and flow cytometry analysis were performed. The results obtained demonstrate that treatment with Rg3-RGE + PT showed synergism to suppress inflammation (in vitro) in RAW 264.7 cells via mitogen-activated protein kinase and nuclear factor κB pathways. Moreover, in C57BL/6 mice, this mixture exhibits strong anti-inflammatory effects in restoring colon length, histopathological damage, pro-inflammatory mediators, and cytokines amount, and decreasing levels of NLRP3 inflammasome (in vivo). Our results recommend that this mixture can be used for the prevention of UC as a prophylactic/therapeutic supplement. 相似文献
18.
Emanuela Colombo Rosaria Pascente Daniela Triolo Claudia Bassani Anthea De Angelis Francesca Ruffini Linda Ottoboni Giancarlo Comi Gianvito Martino Cinthia Farina 《Molecules (Basel, Switzerland)》2020,25(22)
Astrocytes greatly participate to inflammatory and neurotoxic reactions occurring in neurodegenerative diseases and are valuable pharmacological targets to support neuroprotection. Here we used human astrocytes generated from reprogrammed fibroblasts as a cellular model to study the effect of the compound Laquinimod and its active metabolite de-Laquinimod on astrocyte functions and the astrocyte–neuron interaction. We show that human iAstrocytes expressed the receptor for the inflammatory mediator IL1 and responded to it via nuclear translocation of NFκB, an event that did not occur if cells were treated with Laquinimod, indicating a direct anti-inflammatory activity of the drug on the human astrocyte. Similarly, while exposure to IL1 downregulated glial glutamate transporters GLAST and GLT1, treatment with Laquinimod supported maintenance of physiological levels of these proteins despite the inflammatory milieu. Laquinimod also induced nuclear translocation of the aryl hydrocarbon receptor (AHR), suggesting that drug action was mediated by activation of the AHR pathway. However, the drug was effective despite AHR inhibition via CH223191, indicating that AHR signaling in the astrocyte is dispensable for drug responses. Finally, in vitro experiments with rat spinal neurons showed that laquinimod did not exert neuroprotection directly on the neuron but dampened astrocyte-induced neurodegeneration. Our findings indicate that fibroblast-derived human astrocytes represent a suitable model to study astrocyte–neuron crosstalk and demonstrate indirect, partial neuroprotective efficacy for laquinimod. 相似文献
19.
Callicarpalongissima has been used as a Yao folk medicine to treat arthritis for years in China, although its active anti-arthritic moieties have not been clarified so far. In this study, two natural phenolic diterpenoids with anti-rheumatoid arthritis (RA) effects, rosmanol and carnosol, isolated from the medicinal plant were reported on for the first time. In type II collagen-induced arthritis DBA/1 mice, both rosmanol (40 mg/kg/d) and carnosol (40 mg/kg/d) alone alleviated the RA symptoms, such as swelling, redness, and synovitis; decreased the arthritis index score; and downregulated the serum pro-inflammatory cytokine levels of interleukin 6 (IL-6), monocyte chemotactic protein 1 (MCP-1), and tumor necrosis factor α (TNF-α). Additionally, they blocked the activation of the Toll-like receptor 4 (TLR4)/nuclear factor κB (NF-κB)/c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) pathways. Of particular interest was that when they were used in combination (20 mg/kg/d each), the anti-RA effect and inhibitory activity on the TLR4/NF-κB/MAPK pathway were significantly enhanced. The results demonstrated that rosmanol and carnosol synergistically alleviated RA by inhibiting inflammation through regulating the TLR4/NF-κB/MAPK pathway, meaning they have the potential to be developed into novel, safe natural combinations for the treatment of RA. 相似文献
20.
Xu Xiaoyong Zheng Guoguang Wang Qing-an 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,92(1):61-72
This paper experimentally and theoretically examines the scattering properties of simulated non-spherical hydrometeors including water oblates, ice oblates and ice sphere-cone-oblates, in terms of the backscattering cross-section and the differential reflectivity. The experimental measurements of the backscattering cross-sections of non-spherical hydrometeor samples were performed in the Electromagnetic Scattering Laboratory of China National Space Industrial Corporation. Meanwhile, the backscattering cross-sections have been computed with the transition (T) matrix method. The theoretical results are compared with the experimental data, showing that the calculations are consistent with the observations in general. Experimental and theoretical analyses indicate that the backscattering cross-section of non-spherical particles increases as the particle size parameter increases, and fluctuates when the sizes are larger under the effect of resonance scattering. Differential reflectivity ZDR of water oblates in natural rainfall is always greater than 0 dB whereas ZDR of hailstones may be negative. There is a good linear relationship between differential reflectivity and aspect ratio of a particle. These derivations agree with the literature and can be used to identify the presence of hail particles and distinguish between plate-type and columnar-type hydrometeors. In this study, the measuring experiment and the T-matrix method calculations for the scattering of simulated raindrop and ice particles are also briefly described. 相似文献