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排序方式: 共有291条查询结果,搜索用时 15 毫秒
1.
Phorbol esters inhibit inositol phosphate and diacylglycerol formation in proliferating HL60 cells. Relationship to differentiation 总被引:2,自引:0,他引:2
Phorbol 12-myristate 13-acetate (PMA) induces the differentiation of the human promyelocytic cell line, HL60, towards adherent macrophage-like cells within 2 days. We have examined the early effects of PMA on inositol phosphates and on diacylglycerol production, two second messengers derived from inositol lipids. In proliferating HL60 cells, PMA induced a time- and concentration-dependent decrease in inositol phosphate levels. Maximal effects were seen after 1 h at 10 nM PMA. PMA also induced the translocation of protein kinase C from the cytosol to the membrane. Comparison between the differentiating effects of several phorbol esters and of 1-oleoyl-2-acetylglycerol with their ability to inhibit inositol phosphate formation suggests that the two effects are correlated. 相似文献
2.
Martin François-Marie Janssen Philippe Bergès Laurent Dupont Blandine Evette André 《Wetlands Ecology and Management》2021,29(1):27-39
Wetlands Ecology and Management - Riparian corridors play an important role for the maintenance of regional biodiversity and ecosystem functions. Riparian forests are even the only semi-natural... 相似文献
3.
Pedro M. D. Moreno Sylvain Geny Y. Vladimir Pabon Helen Bergquist Eman M. Zaghloul Cristina S. J. Rocha Iulian I. Oprea Burcu Bestas Samir EL Andaloussi Per T. J?rgensen Erik B. Pedersen Karin E. Lundin Rula Zain Jesper Wengel C. I. Edvard Smith 《Nucleic acids research》2013,41(5):3257-3273
In spite of the many developments in synthetic oligonucleotide (ON) chemistry and design, invasion into double-stranded DNA (DSI) under physiological salt and pH conditions remains a challenge. In this work, we provide a new ON tool based on locked nucleic acids (LNAs), designed for strand invasion into duplex DNA (DSI). We thus report on the development of a clamp type of LNA ON—bisLNA—with capacity to bind and invade into supercoiled double-stranded DNA. The bisLNA links a triplex-forming, Hoogsteen-binding, targeting arm with a strand-invading Watson–Crick binding arm. Optimization was carried out by varying the number and location of LNA nucleotides and the length of the triplex-forming versus strand-invading arms. Single-strand regions in target duplex DNA were mapped using chemical probing. By combining design and increase in LNA content, it was possible to achieve a 100-fold increase in potency with 30% DSI at 450 nM using a bisLNA to plasmid ratio of only 21:1. Although this first conceptual report does not address the utility of bisLNA for the targeting of DNA in a chromosomal context, it shows bisLNA as a promising candidate for interfering also with cellular genes. 相似文献
4.
Vélayoudom-Céphise Fritz-Line Rajaobelina Kalina Helmer Catherine Nov Sovanndany Pupier Emilie Blanco Laurence Hugo Marie Farges Blandine Astrugue Cyril Gin Henri Rigalleau Vincent 《Cardiovascular diabetology》2016,15(1):1-9
Type 1 diabetes is associated with increased cardiovascular disease (CVD). Decreased endothelial progenitor cells (EPCs) number plays a pivotal role in reduced endothelial repair and development of CVD. We aimed to determine if cardioprotective effect of metformin is mediated by increasing circulating endothelial progenitor cells (cEPCs), pro-angiogenic cells (PACs) and decreasing circulating endothelial cells (cECs) count whilst maintaining unchanged glycemic control. This study was an open label and parallel standard treatment study. Twenty-three type 1 diabetes patients without overt CVD were treated with metformin for 8 weeks (treatment group-TG). They were matched with nine type 1 diabetes patients on standard treatment (SG) and 23 age- and sex-matched healthy volunteers (HC). Insulin dose was adjusted to keep unchanged glycaemic control. cEPCs and cECs counts were determined by flow cytometry using surface markers CD45dimCD34+VEGFR-2+ and CD45dimCD133−CD34+CD144+ respectively. Peripheral blood mononuclear cells were cultured to assess changes in PACs number, function and colony forming units (CFU-Hill’s colonies). At baseline TG had lower cEPCs, PACs, CFU-Hills’ colonies and PACs adhesion versus HC (p < 0.001-all variables) and higher cECs versus HC (p = 0.03). Metformin improved cEPCs, PACs, CFU-Hill’s colonies number, cECs and PACs adhesion (p < 0.05-all variables) to levels seen in HC whilst HbA1c (one-way ANOVA p = 0.78) and glucose variability (average glucose, blood glucose standard deviation, mean amplitude of glycaemic excursion, continuous overall net glycaemic action and area under curve) remained unchanged. No changes were seen in any variables in SG. There was an inverse correlation between CFU-Hill’s colonies with cECs. Metformin has potential cardio-protective effect through improving cEPCs, CFU-Hill’s colonies, cECs, PACs count and function independently of hypoglycaemic effect. This finding needs to be confirmed by long term cardiovascular outcome studies in type 1 diabetes.
Trial registration ISRCTN26092132 相似文献
5.
Maternal thyroid hormones (THs) have been proven crucial for embryonic development in humans, but their influence within the natural variation on wild animals remains unknown. So far the only two studies that experimentally investigated the potential fitness consequences of maternal THs in birds found inconsistent results. More studies are thus required to assess the general effects of maternal THs and their influences on more behavioral and physiological parameters. In this study, we experimentally elevated yolk TH content in a wild migratory passerine species, the collared flycatcher Ficedula albicollis, to investigate the effects on hatching success, nestling growth and oxidative stress. We found that TH‐injected eggs had a higher hatching success, and the nestlings hatched from TH‐injected eggs were heavier and larger than control nestlings, but only during the early postnatal period. These differences vanished by fledging. Nestlings from TH‐injected eggs exhibited lower activity of the glutathione‐s‐transferase, a major antioxidant enzyme, than control nestlings at day 12, a few days before fledging, but they did not differ in oxidative damage and overall intracellular oxidative state. These results suggest that the early growth‐enhancing effects incurred no observable oxidative stress. We hypothesize that such a transient growth‐enhancing effect might be adaptive in advancing the development and maturation of the offspring so they are well‐prepared in time for the upcoming migration. Further studies investigating whether such advancing effects can influence long‐term fitness, will be more than valuable. 相似文献
6.
In order to gain insights into the evolution of gastrulation mechanisms among vertebrates, we have characterized a Brachyury-related gene in a lamprey, Lampetra fluviatilis, and in a chondrichthyan, Scyliorhinus canicula. These two genes, respectively termed LfT and ScT, share with their osteichthyan counterparts prominent expression sites in the developing notochord, the tailbud, but also a transient expression in the prechordal plate, which is likely to be ancestral among vertebrates. In addition, the lamprey LfT gene is transcribed in the endoderm of the pharyngeal arches and the epiphysis, two expression sites that have not been reported thus far in gnathostomes, and, as in the chick, in the differentiating nephrotomes. Since Brachyury expression in nascent mesoderm and endoderm is highly conserved among vertebrates as well as cephalochordates, we have used this marker to identify these cell populations during gastrulation in the dogfish. The results suggest that these cells are initially present over the whole margin of the blastoderm and are displaced during gastrulation to its posterior part, which may correspond to the site of mesoderm and endoderm internalization. These data provide the first molecular characterization of gastrulation in a chondrichthyan. They indicate that gastrulation in the dogfish and in some amniotes shares striking similarities despite the phylogenetic distance between these species. This supports the hypothesis that the extensively divergent morphologies of gastrulae among vertebrates largely result from adaptations to the presence of yolk. 相似文献
7.
Akendengue B Roblot F Loiseau PM Bories C Ngou-Milama E Laurens A Hocquemiller R 《Phytochemistry》2002,59(8):885-888
Bioguided-fractionation of a CH(2)Cl(2) extract of the stems of Uvaria klaineana (Annonaceae) led to isolation of klaivanolide, a novel bisunsaturated 7-membered lactone (5-acetoxy-7-benzoyloxymethyl-7H-oxepin-2-one), together with benzyl benzoate. Klaivanolide showed potent in vitro antileishmanial activity against both sensitive and amphotericin B-resistant promastigote forms of Leishmania donovani with IC(50) values of 1.75 and 3.12 microM, respectively. The compound also showed in vitro trypanocidal activity against trypomastigote forms of Trypanosoma brucei brucei GVR 35. Its structure was established by 1D and 2D NMR and other spectroscopic techniques. 相似文献
8.
9.
Stéphanie Foulon Tim Greacen Blandine Pasquet Romain Dugravier Thomas Sa?as Nicole Guedeney Antoine Guedeney Florence Tubach CAPEDP Study Group 《PloS one》2015,10(11)