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11.
El Ghazi I Martin BL Armitage IM 《Experimental biology and medicine (Maywood, N.J.)》2006,231(9):1500-1506
Metallothionein (MT)-3, originally called growth inhibitory factor (GIF), was initially identified through its ability to inhibit the growth of neuronal cells in the presence of brain extract. MT-3 is the brain specific isoform of the MT family whose specific biological activity associates it with neurological disorders. Indeed, studies report that MT-3 is decreased by ~30% in brains of patients with Alzheimer disease (AD). Furthermore, many lines of evidence suggest that MT-3 engages in specific protein interactions. To address this, we conducted immunoaffinity chromatography experiments using an immobilized anti-mouse MT-3 antibody. We identified five associated proteins from the pool of sixteen recovered using mass spectrometry and tandem mass spectrometry after in-gel trypsin digestion of bands from the affinity chromatography. The proteins identified were: heat shock protein 84 (HSP84), heat shock protein 70 (HSP70), dihydropyrimidinase-like protein-2 (DRP-2), creatine kinase (CK) and beta-actin. Coimmunoprecipitation experiments, also conducted on whole mouse brain extract using the anti-mouse MT-3 antibody along with commercially available antibodies against HSP84 and CK, confirmed that these three proteins were in a single protein complex. Immunohistochemical experiments were then conducted on the perfused mouse brain that confirmed the in situ colocalization of CK and MT-3 in the hippocampus region. These data provide new insights into the involvement of MT-3 in a multiprotein complex, which will be used to understand the biological activity of MT-3 and its role in neurological disease. 相似文献
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Biotransformation of 4‐fluoro‐N‐(1‐{2‐[(propan‐2‐yl)phenoxy]ethyl}‐8‐azabicyclo[3.2.1]octan‐3‐yl)‐benzenesulfonamide,a novel potent 5‐HT7 receptor antagonist with antidepressant‐like and anxiolytic properties: In vitro and in silico approach 下载免费PDF全文
Karolina Słoczyńska Katarzyna Wójcik‐Pszczoła Vittorio Canale Paweł Żmudzki Paweł Zajdel Elżbieta Pękala 《Journal of biochemical and molecular toxicology》2018,32(5)
The aim of the study was to investigate the metabolism of 4‐fluoro‐N‐(1‐{2‐[(propan‐2‐yl)phenoxy]ethyl}‐8‐azabicyclo[3.2.1]octan‐3‐yl)‐benzenesulfonamide (PZ‐1150), a novel 5‐HT7 receptor antagonist with antidepressant‐like and anxiolytic properties, by the following three ways: in vitro with microsomes; in vitro employing Cunninghamella echinulata, and in silico using MetaSite. Biotransformation of PZ‐1150 with microsomes resulted in five metabolites, while transformation with C. echinulata afforded two metabolites. In both models, the predominant metabolite occurred due to hydroxylation of benzene ring. In silico data coincide with in vitro experiments, as three MetaSite metabolites matched compounds identified in microsomal samples. In human liver microsomes PZ‐1150 exhibited in vitro half‐life of 64 min, with microsomal intrinsic clearance of 54.1 μL/min/mg and intrinsic clearance of 48.7 mL/min/kg. Therefore, PZ‐1150 is predicted to be a high‐clearance agent. The study demonstrated the applicability of using microsomal model coupled with microbial model to elucidate the metabolic pathways of compounds and comparison with in silico metabolite predictions. 相似文献
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Effect of lead stress on mineral content and growth of wheat (Triticum aestivum) and spinach (Spinacia oleracea) seedlings 总被引:1,自引:0,他引:1
Mostafa Lamhamdi Ouiam El Galiou Ahmed Bakrim Juan Carlos Nóvoa-Muñoz Manuel Arias-Estévez Ahmed Aarab René Lafont 《Saudi Journal of Biological Sciences》2013,20(1):29-36
Lead (Pb) is the most common heavy metal contaminant in the environment. Pb is not an essential element for plants, but they absorb it when it is present in their environment, especially in rural areas when the soil is polluted by automotive exhaust and in fields contaminated with fertilizers containing heavy metal impurities. To investigate lead effects on nutrient uptake and metabolism, two plant species, spinach (Spinacia oleracea) and wheat (Triticum aestivum), were grown under hydroponic conditions and stressed with lead nitrate, Pb(NO3)2, at three concentrations (1.5, 3, and 15 mM).Lead is accumulated in a dose-dependent manner in both plant species, which results in reduced growth and lower uptake of all mineral ions tested. Total amounts and concentrations of most mineral ions (Na, K, Ca, P, Mg, Fe, Cu and Zn) are reduced, although Mn concentrations are increased, as its uptake is reduced less relative to the whole plant’s growth. The deficiency of mineral nutrients correlates in a strong decrease in the contents of chlorophylls a and b and proline in both species, but these effects are less pronounced in spinach than in wheat. By contrast, the effects of lead on soluble proteins differ between species; they are reduced in wheat at all lead concentrations, whereas they are increased in spinach, where their value peaks at 3 mM Pb.The relative lead uptake by spinach and wheat, and the different susceptibility of these two species to lead treatment are discussed. 相似文献
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Summary A new form of ectodermal dysplasia was observed in two siblings, offspring of healthy non-consanguineous parents. The main findings in both children are: hypodontia, abnormally shaped teeth, scalp hypotrichosis, pili annulati, follicular hyperkeratosis on the trunk and limbs, intensified delineation and reticular hyperpigmentation of the nape, and hyperopia; one of the siblings also has astigmatism. As both patients have normal nails and are euhidrotic, this is an ectodermal dysplasia of the pilodental subgroup. The cause is probably genetic and autosomal-recessive inheritance is most likely. 相似文献
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Although proteomics has been exploited in a wide range of diseases for identification of biomarkers and pathophysiological mechanisms, there are still biomedical disciplines such as otology where proteomics platforms are underused due to technical challenges and/or complex features of the disease. Thus, in the past few years, healthcare and scientific agencies have advocated the development and adoption of proteomic technologies in otological research. However, few studies have been conducted and limited literature is available in this area. Here, we present the state of the art of proteomics in otology, discussing the substantial evidence from recent experimental models and clinical studies in inner-ear conditions. We also delineate a series of critical issues including minute size of the inner ear, delicacy and poor accessibility of tissue that researchers face while undertaking otology proteomics research. Furthermore, we provide perspective to enhance the impact and lead to the clinical implementation of these proteomics-based strategies. 相似文献
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Ilker Kudret Sariyer Nana Merabova Prem Kumer Patel Tijana Knezevic Alessandra Rosati Maria C. Turco Kamel Khalili 《PloS one》2012,7(9)
JC virus, JCV, is a human neurotropic polyomavirus whose replication in glial cells causes the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML). In addition, JCV possesses oncogenic activity and expression of its transforming protein, large T-antigen (T-Ag), in several experimental animals induces tumors of neural origin. Further, the presence of JCV DNA and T-Ag have been repeatedly observed in several human malignant tissues including primitive neuroectodermal tumors and glioblastomas. Earlier studies have demonstrated that Bag3, a member of the Bcl-2-associated athanogene (Bag) family of proteins, which is implicated in autophagy and apoptosis, is downregulated upon JCV infection of glial cells and that JCV T-Ag is responsible for suppressing the activity of the BAG3 promoter. Here, we investigated the possible impact of Bag3 on T-Ag expression in JCV-infected human primary glial cells as well as in cells derived from T-Ag-induced medulloblastoma in transgenic animals. Results from these studies revealed that overexpression of Bag3 drastically decreases the level of T-Ag expression by inducing the autophagic degradation of the viral protein. Interestingly, this event leads to the inhibition of JCV infection of glial cells, suggesting that the reduced levels of T-antigen seen upon the overexpression of Bag3 has a biological impact on the viral lytic cycle. Results from protein-protein interaction studies showed that T-Ag and Bag3 physically interact with each other through the zinc-finger of T-Ag and the proline rich domains of Bag3, and this interaction is important for the autophagic degradation of T-Ag. Our observations open a new avenue of research for better understanding of virus-host interaction by investigating the interplay between T-Ag and Bag3, and their impact on the development of JCV-associated diseases. 相似文献
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Łukasz Kajtoch Elżbieta Cieślak Zoltán Varga Wojciech Paul Miłosz A. Mazur Gábor Sramkó Daniel Kubisz 《Biodiversity and Conservation》2016,25(12):2309-2339
The phylogeography of species associated with European steppes and extrazonal xeric grasslands is poorly understood. This paper summarizes the results of recent studies on the phylogeography and conservation genetics of animals (20 taxa of beetles, butterflies, reptiles and rodents) and flowering plants (18 taxa) of such, "steppic" habitats in Eastern Central Europe. Most species show a similar phylogeographic pattern: relatively high genetic similarity within regional groups of populations and moderate-to-high genetic distinctiveness of populations from currently isolated regions located in the studied area. This distinctiveness of populations suggests a survival here during glacial maxima, including areas north of the Bohemian Massif-Carpathians arc. Steppic species generally do not follow the paradigmatic patterns known for temperate biota (south-north “contraction–expansion”), but to some extent are similar to those of arctic-alpine taxa. There are three main groups of taxa within Eastern Central Europe that differ in their contemporary distribution pattern, which may reflect historical origin and expansion routes. Present diversity patterns of the studied steppic species suggest that they share a unique genetic signature and distinct assemblages exist in each of the now isolated areas rich in steppic habitats. At least some of these areas probably act as present “interglacial refugia” for steppic species. This study strongly supports the need to protect steppic species throughout their entire ranges in the region, as the continuous destruction of steppic habitats in some areas may lead not only to the disappearance of local populations, but also to the extinction of unique evolutionary units. 相似文献