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101.
102.
Paltrinieri S Spagnolo V Giordano A Gelmetti D Comazzi S 《Journal of cellular physiology》2006,208(2):446-450
It has been postulated that Doppel (Dpl) and Prion (PrP) proteins have yet undetermined interactions, since Dpl is overexpressed in transgenic PrP-deficient mice. In this study we investigated the expression levels of Dpl and PrP on lymphocytes, monocytes and neutrophils (PMNs) isolated from bovine blood and incubated (2 and 18 h) with TNFalpha, IL-1, IL-2, IL-8, C5a, IFNgamma, anti-PrP, and anti-Dpl antibodies by flow cytometry. The isolation procedures yielded cell populations with high purity, viability and recovery rates. After 2 h incubation, expression of PrP or Dpl was altered only in PMNs. These cells overexpressed PrP when incubated with TNFalpha and IFNgamma, and both PrP and Dpl when incubated with C5a; incubation with TNFalpha, IL-8 and IFNgamma led to down-regulation of Dpl. Lymphocytes incubated for 18 h with IL-2 and with IFNgamma overexpressed Dpl. Incubation with the anti-PrP antibody induced down-regulation of Dpl in PMNs after 2 h and overexpression of Dpl in lymphocytes after 18 h. The differences recorded after 2 h were likely due to redistribution of pre-existing PrP or Dpl molecules, while those seen at 18 h were most probably due to increased protein synthesis. The variations seen using the different activators depend on different receptors and/or signaling pathways. These results demonstrate that is possible to alter the expression of Dpl and PrP in blood cells in vitro by incubation with either cytokines or anti-PrP antibodies. This opens an interesting opportunity to study the biology of these proteins using in vitro systems. 相似文献
103.
Michela Campolo Giovanna Casili Marika Lanza Alessia Filippone Marika Cordaro Alessio Ardizzone Sarah Adriana Scuderi Salvatore Cuzzocrea Emanuela Esposito Irene Paterniti 《Journal of cellular and molecular medicine》2021,25(16):7855-7866
Traumatic brain injury (TBI) provokes primary and secondary damage on endothelium and brain parenchyma, leading neurons die rapidly by necrosis. The mammalian target of rapamycin signalling pathway (mTOR) manages numerous aspects of cellular growth, and it is up-regulated after moderate to severe traumatic brain injury (TBI). Currently, the significance of this increased signalling event for the recovery of brain function is unclear; therefore, we used two different selective inhibitors of mTOR activity to discover the functional role of mTOR inhibition in a mouse model of TBI performed by a controlled cortical impact injury (CCI). Treatment with KU0063794, a dual mTORC1 and mTORC2 inhibitor, and with rapamycin as well-known inhibitor of mTOR, was performed 1 and 4 hours subsequent to TBI. Results proved that mTOR inhibitors, especially KU0063794, significantly improved cognitive and motor recovery after TBI, reducing lesion volumes. Also, treatment with mTOR inhibitors ameliorated the neuroinflammation associated with TBI, showing a diminished neuronal death and astrogliosis after trauma. Our findings propose that the involvement of selective mTORC1/2 inhibitor may represent a therapeutic strategy to improve recovery after brain trauma. 相似文献
104.
Primula sect. Aleuritia subsect. Aleuritia (Aleuritia) includes diploid, self-incompatible heterostyles and polyploid, self-compatible homostyles, the latter generally occurring at higher latitudes than the former. This study develops a phylogenetic hypothesis for Aleuritia to elucidate the interactions between Pleistocene glacial cycles, biogeographic patterns, ploidy levels and breeding systems. Sequences from five chloroplast DNA loci were analyzed with parsimony to reconstruct a phylogeny, haplotype network, and ancestral states for ploidy levels and breeding systems.The results supported the monophyly of Aleuritia and four major biogeographic lineages: an amphi-Pacific, a South American, an amphi-Atlantic and a European/North American lineage. At least four independent switches to homostyly and five to polyploidy were inferred. An Asian ancestor probably gave origin to an amphi-Pacific clade and to a lineage that diversified on the European and American continents. Switches to homostyly occurred exclusively in polyploid lineages, which mainly occupy previously glaciated areas. The higher success of the autogamous polyploid species at recolonizing habitats freed by glacial retreat might be explained in terms of selection for reproductive assurance. 相似文献
105.
Galzio R Cristiano L Fidoamore A Cifone MG Benedetti E Cinque B Menghini P Raysi Dehcordi S Ippoliti R Giordano A Cimini A 《Journal of cellular biochemistry》2012,113(11):3342-3352
Gliobastoma (GB), the most common adult brain tumor, infiltrates normal brain area rendering impossible the complete surgical resection, resulting in a poor median survival (14–15 months), despite the aggressive multimodality treatments post‐surgery, such as radiation and chemo‐therapy. GB is characterized by hypoxic and necrotic regions due to a poorly organized tumor vascularization, leading to inadequate blood supply and consequently to hypoxic and necrotic areas. We have previously shown that, under hypoxia GB primary cells increased the expression of stemness markers as well as the expression of the nuclear receptor peroxisome proliferator‐activated receptor α (PPARα) and also the crucial role played by PPARs in mouse neural stem cells maintenance and differentiation. Due to the importance of lipid signaling in cell proliferation and differentiation, in this work, we analyzed the expression of PPARs in GB neurospheres both in normoxic and hypoxic conditions. The results obtained suggest a differential regulation of the three PPARs by hypoxia, thus indicating a possible therapeutic strategy to counteract GB recurrencies. J. Cell. Biochem. 113: 3342–3352, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
106.
Furfaro AL Macay JR Marengo B Nitti M Parodi A Fenoglio D Marinari UM Pronzato MA Domenicotti C Traverso N 《Free radical biology & medicine》2012,52(2):488-496
Cancer cell survival is known to be related to the ability to counteract oxidative stress, and glutathione (GSH) depletion has been proposed as a mechanism to sensitize cells to anticancer therapy. However, we observed that GI-ME-N cells, a neuroblastoma cell line without MYCN amplification, are able to survive even if GSH-depleted by l-buthionine-(S,R)-sulfoximine (BSO). Here, we show that in GI-ME-N cells, BSO activates Nrf2 and up-regulates heme oxygenase-1 (HO-1). Silencing of Nrf2 restrained HO-1 induction by BSO. Inhibition of HO-1 and silencing of Nrf2 or HO-1 sensitized GI-ME-N cells to BSO, leading to reactive oxygen/nitrogen species overproduction and decreasing viability. Moreover, targeting the Nrf2/HO-1 axis sensitized GI-ME-N cells to etoposide more than GSH depletion. Therefore, we have provided evidence that in GI-ME-N cells, the Nrf2/HO-1 axis plays a crucial role as a protective factor against cellular stress, and we suggest that the inhibition of Nfr2/HO-1 signaling should be considered as a central target in the clinical battle against neuroblastoma. 相似文献
107.
108.
Social insect colonies contain attractive resources for many organisms. Cleptoparasites sneak into their nests and steal food resources. Social parasites sneak into their social organisations and exploit them for reproduction. Both cleptoparasites and social parasites overcome the ability of social insects to detect intruders, which is mainly based on chemoreception. Here we compared the chemical strategies of social parasites and cleptoparasites that target the same host and analyse the implication of the results for the understanding of nestmate recognition mechanisms. The social parasitic wasp Polistes atrimandibularis (Hymenoptera: Vespidae), and the cleptoparasitic velvet ant Mutilla europaea (Hymenoptera: Mutillidae), both target the colonies of the paper wasp Polistes biglumis (Hymenoptera: Vespidae). There is no chemical mimicry with hosts in the cuticular chemical profiles of velvet ants and pre-invasion social parasites, but both have lower concentrations of recognition cues (chemical insignificance) and lower proportions of branched alkanes than their hosts. Additionally, they both have larger proportions of alkenes than their hosts. In contrast, post-invasion obligate social parasites have proportions of branched hydrocarbons as large as those of their hosts and their overall cuticular profiles resemble those of their hosts. These results suggest that the chemical strategies for evading host detection vary according to the lifestyles of the parasites. Cleptoparasites and pre-invasion social parasites that sneak into host colonies limit host overaggression by having few recognition cues, whereas post-invasion social parasites that sneak into their host social structure facilitate social integration by chemical mimicry with colony members. 相似文献
109.
C Daleno A Piralla A Scala F Baldanti V Usonis N Principi S Esposito 《Journal of virology》2012,86(19):10888-10889
The new enterovirus C-117 strain belongs to the human enterovirus C species in the Picornaviridae family. We describe the characterization of the complete genome of this strain identified in a respiratory specimen of a child enrolled in the Community-Acquired Pneumonia Pediatric Research Initiative (CAP-PRI) study evaluating the etiology of community-acquired pneumonia (CAP). 相似文献
110.
Alessandra Fierabracci Carla Bizzarri Alessia Palma Annamaria Milillo Emanuele Bellacchio Marco Cappa 《Gene》2012