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21.
Fernanda R. Santana Liany Luna-Dulcey Víctor U. Antunes Claudio F. Tormena Marcia R. Cominetti Marcelo C. Duarte 《Natural product research》2020,34(1):102-109
AbstractHyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC50 of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC50 sufficiently low to be considered as a drug prototype. 相似文献
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Pedro L. R. Guedes Carolina P. F. Carvalho Adriana A. F. Carbonel Manuel J. Simes Marcelo Y. Icimoto Jair A. K. Aguiar Maria Kouyoumdjian Marcos L. Gazarini Marcia R. Nagaoka 《Molecules (Basel, Switzerland)》2022,27(3)
During liver fibrogenesis, there is an imbalance between regeneration and wound healing. The current treatment is the withdrawal of the causing agent; thus, investigation of new and effective treatments is important. Studies have highlighted the action of chondroitin sulfate (CS) in different cells; thus, our aim was to analyze its effect on an experimental model of bile duct ligation (BDL). Adult Wistar rats were subjected to BDL and treated with CS for 7, 14, 21, or 28 days intraperitoneally. We performed histomorphometric analyses on Picrosirius-stained liver sections. Cell death was analyzed according to caspase-3 and cathepsin B activity and using a TUNEL assay. Regeneration was evaluated using PCNA immunohistochemistry. BDL led to increased collagen content with corresponding decreased liver parenchyma. CS treatment reduced total collagen and increased parenchyma content after 21 and 28 days. The treatment also promoted changes in the hepatic collagen type III/I ratio. Furthermore, it was observed that CS treatment reduced caspase-3 activity and the percentage of TUNEL-positive cells after 14 days and cathepsin B activity only after 28 days. The regeneration increased after 14, 21, and 28 days of CS treatment. In conclusion, our study showed a promising hepatoprotective action of CS in fibrogenesis induced by BDL. 相似文献
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Steven J. Langford Marcia A.-P. Lee Katherine J. Macfarlane Josephine A. Weigold 《Journal of inclusion phenomena and macrocyclic chemistry》2001,41(1-4):135-139
A series of complexes of the type [Sn(TTP)L2] have been prepared by the condensation of [Sn(TTP)OH2] (TTP = meso-tetratolylporphyrin) with a range of substituted phenols. The resulting complexes were characterised using 1H NMR and single crystal X-ray diffraction techniques. In each case, the condensation of the phenols with the Sn(IV)porphyrin in CDCl3 solution is slow (h) but essentially quantitative. The slow kinetics of the formation of the diaxial phenolate complexes allows for the identification, by 1H NMR spectroscopy, of three independent complexes within this process, namely an outer-sphere (H-bonded) complex as well as two independent phenolate complexes. The rate of condensation is in the order phenol 4-methoxyphenol > 4-nitrophenol and suggests a steric rather than pKa dependency. 相似文献
24.
Tatsiana Mironava Michael Hadjiargyrou Marcia Simon Miriam H. Rafailovich 《Photochemistry and photobiology》2012,88(6):1497-1506
Compact fluorescent light (CFL) bulbs can provide the same amount of lumens as incandescent light bulbs, using one quarter of the energy. Recently, CFL exposure was found to exacerbate existing skin conditions; however, the effects of CFL exposure on healthy skin tissue have not been thoroughly investigated. In this study, we studied the effects of exposure to CFL illumination on healthy human skin tissue cells (fibroblasts and keratinocytes). Cells exposed to CFLs exhibited a decrease in the proliferation rate, a significant increase in the production of reactive oxygen species, and a decrease in their ability to contract collagen. Measurements of UV emissions from these bulbs found significant levels of UVC and UVA (mercury [Hg] emission lines), which appeared to originate from cracks in the phosphor coatings, present in all bulbs studied. The response of the cells to the CFLs was consistent with damage from UV radiation, which was further enhanced when low dosages of TiO2 nanoparticles (NPs), normally used for UV absorption, were added prior to exposure. No effect on cells, with or without TiO2 NPs, was observed when they were exposed to incandescent light of the same intensity. 相似文献
25.
Marcelo T. Oliveira Ana Flávia L. Specian Célia G.T.J. Andrade Emanuele J.G. Fran?a Luciana Furlaneto-Maia Marcia C. Furlaneto 《Micron (Oxford, England : 1993)》2010,41(6):604-608
Candida parapsilosis is found frequently as commensal organism on epithelial tissues, and is also an increasing cause of nosocomial infection. Scanning electron microscope (SEM) observations were used to analyse the capability of C. parapsilosis cells to adhere and grow as biofilm on human natural substrates and to compare the adherence pattern of isolates exhibiting distinct phenotypes. Cells from the crepe phenotype are predominantly elongated and form pseudohyphae whereas cells from the smooth phenotype are yeast-shaped, either in liquid cultures or on human nail and hair surfaces. The electron micrographs revealed that C. parapsilosis cells from the smooth phenotype adhered in higher number to both surfaces compared to the observed for the crepe phenotype. SEM analysis of human hair surface revealed that cells from the smooth phenotype appear as clumped blastoconidia of uniform morphology embedded in a flocculent extracellular material forming biofilm. The extracellular material and biofilm were seeing in a less extension in the crepe phenotype. A distinct adherence pattern was observed when human nail was used as substrate. Here C. parapsilosis cells seem to be linked to surface structures of human nail plate. Fibrillar extracellular material was observed connecting neighbouring cells as well as nail surface. 相似文献
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Reyes-Chilpa R Jiménez-Estrada M Godínez MV Hernández-Ortega S Campos M Béjar E 《Natural product letters》2002,16(4):239-242
A new cacalolide sesquiterpenoid, named as Romo-A, was isolated from the roots of Psacalium decompositum, Asteraceae, a Mexican medicinal shrub with antidiabetic properties. Its structure was elucidated by NMR, MS, IR, UV, and confirmed by X-ray diffraction studies. 相似文献
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Chad?A?Dickey Marcia?N?Gordon Donna?M?Wilcock Donna?L?Herber Melissa?J?Freeman Dave?MorganEmail author 《BMC neuroscience》2005,6(1):7