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991.
Luciane A. Faine Danielle M.H. Cavalcanti Martina Rudnicki Simone Ferderbar Sandra M.D. Macedo Heraldo P. Souza Sandra H.P. Farsky Lisardo Boscá Dulcineia Saes Parra Abdalla 《The Journal of nutritional biochemistry》2010,21(2):125-132
The vascular effects of nitrolinoleate (LNO2), an endogenous product of linoleic acid (LA) nitration by nitric oxide-derived species and a potential nitrosating agent, were investigated on rat endothelial-leukocyte interactions. Confocal microscopy analysis demonstrated that LNO2 was capable to deliver free radical nitric oxide (·NO) into cells, 5 min after its administration to cultured cells, with a peak of liberation at 30 min. THP-1 monocytes incubated with LNO2 for 5 min presented nitrosation of CD40, leading to its inactivation. Other anti-inflammatory actions of LNO2 were observed in vivo by intravital microscopy assays. LNO2 decreased the number of adhered leukocytes in postcapillary venules of the mesentery network. In addition to this, LNO2 reduced mRNA and protein expression of β2-integrin in circulating leukocytes, as well as VCAM-1 in endothelial cells isolated from postcapillary venules, confirming its antiadhesive effects on both cell types. Moreover, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, a nitric oxide scavenger, partially abolished the inhibitory action of LNO2 on leukocyte-endothelium interaction, suggesting that the antiadhesion effects of LNO2 involve a dual role in leukocyte adhesion, acting as a nitric oxide donor as well as through nitric oxide-independent mechanisms. In conclusion, LNO2 inhibited adhesion molecules expression and promoted ·NO inactivation of the CD40–CD40L system, both important processes of the inflammatory response. 相似文献
992.
Paola Palozza Rossella Simone Assunta Catalano Alma Boninsegna Volker Böhm Kati Fröhlich Maria Cristina Mele Giovanni Monego Franco O. Ranelletti 《The Journal of nutritional biochemistry》2010,21(1):34-46
The present study was undertaken to examine whether lycopene is able to counteract 7-ketocholesterol (7-KC)-induced oxidative stress and apoptosis in human macrophages. Human THP-1 macrophages were exposed to 7-KC (10–25 μM) alone and in combination with lycopene (0.5–2 μM), and we monitored changes in cell oxidative status [reactive oxygen species (ROS) production, NOX-4, hsp70 and hsp90 expressions, 8-OHdG formation] and in cell proliferation and apoptosis. After 24 h of treatment, lycopene significantly reduced the increase in ROS production and in 8-OHdG formation induced by the oxysterol in a dose-dependent manner. Moreover, the carotenoid strongly prevented the increase of NOX-4, hsp70 and hsp90 expressions as well as the phosphorylation of the redox-sensitive p38, JNK and ERK1/2 induced by the oxysterol. The attenuation of 7-KC-induced oxidative stress by lycopene coincided with a normalization of cell growth in human macrophages. Lycopene prevented the arrest in G0/G1 phase of cell cycle induced by the oxysterol and counteracted the increased expression of p53 and p21. Concomitantly, it inhibited 7-KC-induced apoptosis, by limiting caspase-3 activation and the modulatory effects of 7-KC on AKT, Bcl-2, Bcl-xL and Bax. Comparing the effects of lycopene, β-carotene and (5Z)-lycopene on ROS production, cell growth and apoptosis show that lycopene and its isomer were more effective than β-carotene in counteracting the dangerous effects of 7-KC in human macrophages. Our study suggests that lycopene may act as a potential antiatherogenic agent by preventing 7-KC-induced oxidative stress and apoptosis in human macrophages. 相似文献
993.
Objectives: Translational research using adult stem cells derived from various tissues has been highlighted in cell‐based therapy. However, there are many limitations to using conventional culture systems of adult stem cells for clinically applicability, including limited combinations of cytokines and use of nutrients derived from animals. Here, we have investigated the effects of placental extract (PE) for culture of placenta‐derived stem cells (PDSCs) as well as their potential for hepatogenic differentiation. Materials and methods: Placental extract, extracted using water‐soluble methods, was used as a supplement for culture of PDSCs. Cell viability was determined using the MTT assay, and cytokine assay was performed using Luminex assay kit. Gene expression, indocyanine green (ICG) up‐take, PAS (Periodic Acid‐Schiff) staining and urea production were also analysed. Results: The placental extract contained several types of cytokine and chemokine essential for maintenance and differentiation of stem cells. Expression of stemness markers in PDSCs cultured with PE is no different from that of PDSCs cultured with foetal bovine serum (FBS). After hepatogenic differentiation, expression patterns for hepatocyte‐specific markers in PDSCs cultured with PE were consistent and potential for hepatogenic differentiation of PDSCs cultured with PE was similar to that of PDSCs cultured with FBS, as shown by PAS staining and urea production assays. Conclusions: Our findings revealed that placental extract could be used as a new component for culture of adult stem cells, as well as for development of human‐based medium, in translational research for regenerative medicine. 相似文献
994.
995.
Simone Fattorini 《Biodiversity and Conservation》2010,19(12):3413-3429
The conservation status of invertebrates is usually lesser known than that of vertebrates, and strategies to identify biotopes
to preserve invertebrate diversity are typically based on a single surrogate taxon, or even on the use of vertebrates as surrogates.
Aim of this research is to illustrate a method for biotope prioritisation that can be easily adapted to different animal groups
and geographical contexts. A two-step protocol for biotope prioritisation is proposed on the basis of a multidimensional characterisation
of species vulnerability. Firstly, species vulnerability is estimated from rarity measures which include geographical range,
abundance and biotope specialisation. Then, these values of vulnerability are used to rank biotopes. The method was applied
here to the tenebrionid beetles, the butterflies, the birds and the mammals of the Central Apennines, a montane area of high
conservation concern for South Europe. This study provides evidence for the importance of including insects in conservation
decisions, because vertebrates are poor surrogates for insects. Conservation efforts in the reserves included in the study
area are mostly focused on vertebrates, for which woodlands are considered particularly important. However high altitude open
biotopes are crucial for both tenebrionids and butterflies, and preservation of such kind of biotopes would be beneficial
also for vertebrates. The approach applied here demonstrates that (1) vertebrates are poor surrogates for insects, and (2)
measures of species rarity, typically used in vertebrate conservation, can be obtained also for insects, for which a veritable
amount of data are hidden in specialised literature and museum collections. 相似文献
996.
997.
Alexey Rivkin Sean P. Ahearn Stephanie M. Chichetti Christopher L. Hamblett Yudith Garcia Michelle Martinez Jed L. Hubbs Michael H. Reutershan Matthew H. Daniels Phieng Siliphaivanh Karin M. Otte Chaomin Li Andrew Rosenau Laura M. Surdi Joon Jung Bethany L. Hughes Jamie L. Crispino George N. Nikov Richard E. Middleton Christopher M. Moxham Mark S. Shearman 《Bioorganic & medicinal chemistry letters》2010,20(7):2279-2282
The development of a novel series of purines as γ-secretase modulators for potential use in the treatment of Alzheimer’s disease is disclosed herein. Optimization of a previously disclosed pyrimidine series afforded a series of potent purine-based γ-secretase modulators with 300- to 2000-fold in vitro selectivity over inhibition of Notch cleavage and that selectively reduces Αβ42 in an APP-YAC transgenic mouse model. 相似文献
998.
999.
Fabrizio Micheli Daniele Andreotti Simone Braggio Anna Checchia 《Bioorganic & medicinal chemistry letters》2010,20(15):4566-4568
A direct and specific comparison of a trifluoromethyl group with the corresponding pentafluorosulfanyl group is made in terms of primary affinity and pharmacokinetic properties. 相似文献
1000.
Hee Jin Kim Myung-Ho Jung Hwan Kim Mohammed I. El-Gamal Tae Bo Sim So Ha Lee Jun Hee Hong Jung-Mi Hah Jung-Hyuck Cho Jung Hoon Choi Kyung Ho Yoo Chang-Hyun Oh 《Bioorganic & medicinal chemistry letters》2010,20(1):413-417
Synthesis of a new series of diarylureas and amides having pyrrolo[3,2-b]pyridine scaffold is described. Their in vitro antiproliferative activity against human melanoma cell line A375 and HS 27 human fibroblast cell line was tested and the effect of substituents on the pyrrolo[3,2-b]pyridine was investigated. The newly synthesized compounds, except meta-substituted derivatives (Ij–k and Iv–w), generally showed superior or similar activity against A375 to Sorafenib. Among all of these derivatives, compounds Ir and It having 5-benzylamide substituted 4′-amide moieties showed the most potent antiproliferative activity against A375. 相似文献