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排序方式: 共有92条查询结果,搜索用时 15 毫秒
1.
Tomasz Wasiewicz Paulina Szyszka Miroslawa Cichorek Zorica Janjetovic Robert C. Tuckey Andrzej T. Slominski Michal A. Zmijewski 《International journal of molecular sciences》2015,16(4):6645-6667
Deregulated melanogenesis is involved in melanomagenesis and melanoma progression and resistance to therapy. Vitamin D analogs have anti-melanoma activity. While the hypercalcaemic effect of the active form of Vitamin D (1,25(OH)2D3) limits its therapeutic use, novel Vitamin D analogs with a modified side chain demonstrate low calcaemic activity. We therefore examined the effect of secosteroidal analogs, both classic (1,25(OH)2D3 and 25(OH)D3), and novel relatively non-calcemic ones (20(OH)D3, calcipotriol, 21(OH)pD, pD and 20(OH)pL), on proliferation, colony formation in monolayer and soft-agar, and mRNA and protein expression by melanoma cells. Murine B16-F10 and hamster Bomirski Ab cell lines were shown to be effective models to study how melanogenesis affects anti-melanoma treatment. Novel Vitamin D analogs with a short side-chain and lumisterol-like 20(OH)pL efficiently inhibited rodent melanoma growth. Moderate pigmentation sensitized rodent melanoma cells towards Vitamin D analogs, and altered expression of key genes involved in Vitamin D signaling, which was opposite to the effect on heavily pigmented cells. Interestingly, melanogenesis inhibited ligand-induced Vitamin D receptor translocation and ligand-induced expression of VDR and CYP24A1 genes. These findings indicate that melanogenesis can affect the anti-melanoma activity of Vitamin D analogs in a complex manner. 相似文献
2.
Flavonoid pigments in chalkhill blue (Lysandra coridon Poda) and other lycaenid butterflies 总被引:1,自引:0,他引:1
Angela Wilson 《Journal of chemical ecology》1987,13(3):473-493
Nine flavonoids, namely, kaempferol, kaempferol 7-rharanoside, kaempferol 3-rhamnoside, kaempferol 3-glucoside, kaempferol 3-glucoside, 7-rhamnoside, quercetin 3-glucoside, quercetin 3,7-diglucoside, isorhamnetin 3-glucoside, and isorhamnetin 3,7-diglucoside, have been identified in the body and wings of the chalkhill blue butterflyLysandra coridon Poda. Flavonoids have also been found in 15 of a further 17 lycaenid species examined. Analysis of the two-dimensional paper chromatographic flavonoid patterns and aglycone results has shown that the flavonoid content ofL. coridon and the other lycaenids is dependent on the flavonoid content of the larval diet. Differences in the flavonoid patterns ofL. coridon and its leguminous larval food plantsHippocrepis comosa, Anthyllis vulneraria, andLotus corniculatus, indicate that the ingested flavonoids are metabolized byL. coridon or its gut flora before sequestration. Despite the presence of fiavones, glycoflavones, and isoflavones in the larval food plant species, only flavonols are sequestered by the lycaenid species examined. The relationship between lycaenid butterflies and their larval food plants, and the possible role(s) of flavonoids in lycaenids has been discussed. Interactions between ants, plants, flavonoids, and myrmecophilous lycaenids have also been considered. 相似文献
3.
Zhao-Jun Pan Ya-Chi Nien Yu-An Shih Tsun-Ying Chen Wen-Dar Lin Wen-Hsi Kuo Hao-Chun Hsu Shih-Long Tu Jen-Chih Chen Chun-Neng Wang 《International journal of molecular sciences》2022,23(4)
The establishment of dorsal–ventral (DV) petal asymmetry is accompanied by differential growth of DV petal size, shape, and color differences, which enhance ornamental values. Genes involved in flower symmetry in Sinningia speciosa have been identified as CYCLOIDEA (SsCYC), but which gene regulatory network (GRN) is associated with SsCYC to establish DV petal asymmetry is still unknown. To uncover the GRN of DV petal asymmetry, we identified 630 DV differentially expressed genes (DV-DEGs) from the RNA-Seq of dorsal and ventral petals in the wild progenitor, S. speciosa ‘ES’. Validated by qRT-PCR, genes in the auxin signaling transduction pathway, SsCYC, and a major regulator of anthocyanin biosynthesis were upregulated in dorsal petals. These genes correlated with a higher endogenous auxin level in dorsal petals, with longer tube length growth through cell expansion and a purple dorsal color. Over-expression of SsCYC in Nicotiana reduced petal size by regulating cell growth, suggesting that SsCYC also controls cell expansion. This suggests that auxin and SsCYC both regulate DV petal asymmetry. Transiently over-expressed SsCYC, however, could not activate most major auxin signaling genes, suggesting that SsCYC may not trigger auxin regulation. Whether auxin can activate SsCYC or whether they act independently to regulate DV petal asymmetry remains to be explored in the future. 相似文献
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P. Khazaeli R. Goldoozian† F. Sharififar‡ 《International journal of cosmetic science》2009,31(5):375-381
This study aimed to evaluate the free radical scavenging and inhibition properties of five medicinal plants, including Quercus infectoria Olive., Terminalia chebula Retz. , Lavendula stoechas L., Mentha longifolia L., Rheum palmatum L., toward the activity of mushroom tyrosinase using l -tyrosine and l -3,4-dihydroxyphenylalanine ( l -DOPA) as the substrate. The methanol extracts of Q. infectoria and T. chebula showed strong radical scavenging effect in 2,2'-dipheny l -1-picrylhydrazyl (DPPH) assay (IC50 = 15.3 and 82.2 μg mL−1 respectively). These plants also showed inhibitory effects against the activity of mushroom tyrosinase in hydroxylation of l -tyrosine (85.9% and 82.2% inhibition, respectively). These two plants also inhibited the oxidation of l -DOPA similar to kojic acid as positive control (IC50 = 102.8 and 192.6 μg mL−1 respectively). In general Q. infectoria and T. chebula significantly inhibited tyrosinase activity and DPPH radical. Both activities were concentration-dependant but not in linear manner. It is needed to study the cytotoxicity of these plant extracts in pigment cell culture before further evaluation and moving to in vivo conditions. 相似文献
8.
Kantesh Balani Flavia C. Brito Lidia Kos Arvind Agarwal 《Journal of the Royal Society Interface》2009,6(40):1097-1102
Pigmentation of murine cardiac tricuspid valve leaflet is associated with melanocyte concentration, which affects its stiffness. Owing to its biological and viscoelastic nature, estimation of the in situ stiffness measurement becomes a challenging task. Therefore, quasi-static and nanodynamic mechanical analysis of the leaflets of the mouse tricuspid valve is performed in the current work. The mechanical properties along the leaflet vary with the degree of pigmentation. Pigmented regions of the valve leaflet that contain melanocytes displayed higher storage modulus (7–10 GPa) than non-pigmented areas (2.5–4 GPa). These results suggest that the presence of melanocytes affects the viscoelastic properties of the mouse atrioventricular valves and are important for their proper functioning in the organism. 相似文献
9.
M.R. Brett‐Crowther 《The International journal of environmental studies》2013,70(1-2):129-131
MAKING EUROPEAN POLICIES WORK: The implementation of Community legislation in the Member States, eds. (Heinrich Siedentopf and Jacques Ziller. European Institute of Public Administration/SAGE Publications, London, 1988. Vol One: Comparative Synthesis, 288 pp., cloth (£30); Vol Two: National reports, 736 pp., cloth (£45). 相似文献
10.
Commercial grade aluminum was anodized to form porous anodic films using alternating current at a voltage of 15 V and a temperature of 25°C. The AC anodization was implemented in phosphoric acid and in an electrolyte modified by dissolving 1.1 g/l iron powder. The presence of iron species in the modified electrolyte did not make iron to be incorporated in the film and appeared not to change the pore diameter, but doubled the film thickness. Electrodeposition of nickel was carried out to pigment the films. Pores of the films produced in the modified electrolyte were also found more accessible for nickel pigmentation. Reflectance spectrum of a nickel-pigmented film produced in the modified electrolyte was measured, and its solar absorptance and thermal emittance were calculated. It has been shown that AC anodization of aluminum in phosphoric acid modified by a small number of intentionally added species such as iron species, followed by electrodeposition of nickel, has potential in developing a method for cheaply preparing selective solar absorbing surface of nickel-pigmented anodic films of aluminum. 相似文献