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Capsule Adoptions occurred at low rate (2.6% of successful nests and 1.1% of fledglings), probably as a result of a mistake in early offspring recognition. 相似文献
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Traditionally the hERG1 potassium channel has been known to have a fundamental role in membrane excitability of several mammalian cells including cardiac myocytes. hERG1 has recently been found to be expressed in non-excitable cancer cells of different histogenesis, but the role of this channel in cancer biology is unknown. Results form recent studies on the effect hERG1 inhibition in some breast cancer cells are controversial as it can lead to apoptosis or protect against cell death. Nevertheless, these data suggest that the hERG1 channel could have an important role in cancer biology. Here we report the effects of hyperstimulation of hERG1 channel in human mammary gland adenocarcinoma-derived cells. Application of the hERG1 activator, the diphenylurea derivative NS1643, inhibits cell proliferation irreversibly. This event is accompanied by a preferential arrest of the cell cycle in G0/G1 phase without the occurrence of apoptotic events. Consequently, cells responded to NS1643 by developing a senescence-like phenotype associated with increased protein levels of the tumor suppressors p21 and p16INK4a and by a positive β-galactosidase assay. These data suggest that prolonged stimulation of the hERG1 potassium channel may activate a senescence program and offers a compelling opportunity to develop a potential antiproliferative cancer therapy. 相似文献
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Seyyed Saeed HOSSEINIAN YOUSEFKHANI Gentile Francesco FICETOLA Nasrullah RASTEGAR-POUYANI Natalia B ANANJEVA Eskandar RASTEGAR-POUYANI Rafaqat MASROOR 《亚洲两栖爬行动物研究(英文版)》2013,(3):207-213
Predictive potential distribution modeling is crucial in outlining habitat usage and establishing conservation management priorities. In this paper we provide detailed data on the distribution of the Caucasian rock agama Para- laudakia caucasia, and use species distribution models (MAXENT) to evaluate environmental suitability and potential distribution at a broad spatial scale. Locality data on the distribution of P. caucasia have been gathered over nearly its entire range by various authors from field surveys. The distribution model ofP caucasia showed good performance (AUC = 0.887), and predicted high suitability in regions mainly located in Tajikistan, north Pakistan, Afghanistan, southeast Turkmenistan, northeast Iran along the Elburz mountains, Transcaueasus (Azerbajan, Armenia, Georgia), northeastern Turkey and northward along the Caspian Sea coast in Daghestan, Russia. The identification of suitable areas for this species will help to assess conservation status of the species, and to set up management programs. 相似文献
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Vascular targeting of malignant tissues with systemically injected nanoparticles (NPs) holds promise in molecular imaging and anti-angiogenic therapies. Here, a computational model is presented to predict the development of tumor neovasculature over time and the specific, vascular accumulation of blood-borne NPs. A multidimensional tumor-growth model is integrated with a mesoscale formulation for the NP adhesion to blood vessel walls. The fraction of injected NPs depositing within the diseased vasculature and their spatial distribution is computed as a function of tumor stage, from 0 to day 24 post-tumor inception. As the malignant mass grows in size, average blood flow and shear rates increase within the tumor neovasculature, reaching values comparable with those measured in healthy, pre-existing vessels already at 10 days. The NP vascular affinity, interpreted as the likelihood for a blood-borne NP to firmly adhere to the vessel walls, is a fundamental parameter in this analysis and depends on NP size and ligand density, and vascular receptor expression. For high vascular affinities, NPs tend to accumulate mostly at the inlet tumor vessels leaving the inner and outer vasculature depleted of NPs. For low vascular affinities, NPs distribute quite uniformly intra-tumorally but exhibit low accumulation doses. It is shown that an optimal vascular affinity can be identified providing the proper balance between accumulation dose and uniform spatial distribution of the NPs. This balance depends on the stage of tumor development (vascularity and endothelial receptor expression) and the NP properties (size, ligand density and ligand-receptor molecular affinity). Also, it is demonstrated that for insufficiently developed vascular networks, NPs are transported preferentially through the healthy, pre-existing vessels, thus bypassing the tumor mass. The computational tool described here can effectively select an optimal NP formulation presenting high accumulation doses and uniform spatial intra-tumor distributions as a function of the development stage of the malignancy. 相似文献
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Cristina Zennaro Maria Pia Rastaldi Lorella Pascolo Marco Stebel Elisa Trevisan Mary Artero Claudio Tiribelli Vittorio Di Maso Michele Carraro 《PloS one》2013,8(6)
Several complex mechanisms contribute to the maintenance of the intricate ramified morphology of glomerular podocytes and to interactions with neighboring cells and the underlying basement membrane. Recently, components of small molecule transporter families have been found in the podocyte membrane, but expression and function of membrane transporters in podocytes is largely unexplored. To investigate this complex field of investigation, we used two molecules which are known substrates of membrane transporters, namely Penicillin G and Puromycin Aminonucleoside (PA).We observed that Penicillin G pre-administration prevented both in vitro and in vivo podocyte damage caused by PA, suggesting the engagement of the same membrane transporters by the two molecules. Indeed, we found that podocytes express a series of transporters which are known to be used by Penicillin G, such as members of the Organic Anion Transporter Polypeptides (OATP/Oatp) family of influx transporters, and P-glycoprotein, a member of the MultiDrug Resistance (MDR) efflux transporter family.Expression of OATP/Oatp transporters was modified by PA treatment. Similarly, in vitro PA treatment increased mRNA and protein expression of P-glycoprotein, as well as its activity, confirming the engagement of the molecule upon PA administration.In summary, we have characterized some of the small molecule transporters present at the podocyte membrane, focusing on those used by PA to enter and exit the cell. Further investigation will be needed to understand precisely the role of these transporter families in maintaining podocyte homeostasis and in the pathogenesis of podocyte injury. 相似文献
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Giobbe S Marceddu S Scherm B Zara G Mazzarello VL Budroni M Migheli Q 《FEMS yeast research》2007,7(8):1389-1398
A biofilm-forming strain of Pichia fermentans proved to be most effective in controlling brown rot on apple fruit when coinoculated into artificial wounds with a phytopathogenic isolate of Monilinia fructicola. Culture filtrates and autoclaved cells had no significant influence on the disease. When sprayed onto the apple fruit surface, this yeast formed a thin biofilm but failed to colonize the underlying tissues. When inoculated into wounds artificially inflicted to peach fruit or when sprayed onto the surface of peach fruit, the same strain showed an unexpected pathogenic behaviour, causing rapid decay of fruit tissues even in the absence of M. fructicola. Both optical and scanning electron microscopy were used to evaluate the pattern of fruit tissue colonization by P. fermentans. While on apple surface and within the apple wound the antagonist retained its yeast-like shape, colonization of peach fruit tissue was always characterized by a transition from budding growth to pseudohyphal growth. These results suggest that pseudohyphal growth plays a major role in governing the potential pathogenicity of P. fermentans, further emphasizing the importance of a thorough risk assessment for the safe use of any novel biocontrol agent. 相似文献