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151.
AbstractThe need to optimize seed banking efforts has stimulated research for rapid methods to estimate quality in seed-lots. For terrestrial orchids, viability testing using tetrazolium (TTC) staining requires chemical scarification, as seeds have an impermeable testa. Different seed-coat permeability may affect TTC staining, thus affecting the results. The aim of this study was to perform a permeability test to assess the effectiveness of the used scarification method and its usefulness to correct TTC viability results. Mature seeds of Anacamptis laxiflora were subjected to eight scarification treatments with sodium hypochlorite solutions with different concentration and duration. Viability tests were performed using the basic TTC methodology, followed by a permeability test performed by means of trypan blue dye. The different scarification methods resulted in estimated TTC viability ranging from 0% and 94% for the same seed lot of A. laxiflora seeds. Our results proved that the used scarification protocol significantly affects both seed coat permeability and subsequent TTC staining (two-way ANOVA, p?< 0.0001). We describe a new rapid protocol that can be used to test terrestrial orchid seed viability. This double-staining method, providing rapid information on seed coat permeability, can be useful to avoid under-estimation of TTC results. 相似文献
152.
Harun Patel Rahul Pawara Iqrar Ansari Harsha Jadhav Sanjay Surana 《Journal of receptor and signal transduction research》2013,33(5-6):393-412
AbstractCardiotoxicity is one amongst the adverse effect of Osimertinib delineate in clinical trials and related to escalating doses. To triumph over the drawbacks of Osimertinib, in this study, we tend to delineate the design, synthesis, in vitro biological analysis of a series of novel reversible selective T790M inhibitors with minimal cardiotoxicity. Amongst the virtually sorted compounds; compound 18 and 74 have been located to be the foremost active compounds of the series with IC50 value of 0.88, 0.92?μM in cellular assay and 0.56, 0.62?μM in enzymatic assay, against double mutant L858R/T790M EGFR. Additionally, they showed much less affinity toward wild-type (WT)-EGFR with minimal cardiotoxicity. 相似文献
153.
A major difficulty in addressing chemical mixtures through legislation or regulations revolves around our limited understanding of their potential impacts. This review provides an overview of recent research on pesticide mixture toxicity to aquatic biota and the methods employed to predict toxic effects. The most common approaches are to assume concentration-addition or independent action of chemicals in a mixture. There are a number of cases in the literature of interactions between pesticides. However, models accounting for possible interactions between mixture components are used infrequently. Although results are limited, studies investigating the effects of pesticide mixtures have not demonstrated significant synergism at environmentally relevant concentrations. Based on the results of our review, we conclude that the concentration-addition model is a generally conservative and practical first-tier model for the ecological assessment of pesticide mixtures in aquatic systems. 相似文献
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Hiramani Dhungana Tarja Malm Adam Denes Piia Valonen Sara Wojciechowski Johanna Magga Ekaterina Savchenko Neil Humphreys Richard Grencis Nancy Rothwell Jari Koistinaho 《Aging cell》2013,12(5):842-850
Ischemic stroke is confounded by conditions such as atherosclerosis, diabetes, and infection, all of which alter peripheral inflammatory processes with concomitant impact on stroke outcome. The majority of the stroke patients are elderly, but the impact of interactions between aging and inflammation on stroke remains unknown. We thus investigated the influence of age on the outcome of stroke in animals predisposed to systemic chronic infection. Th1‐polarized chronic systemic infection was induced in 18–22 month and 4‐month‐old C57BL/6j mice by administration of Trichuris muris (gut parasite). One month after infection, mice underwent permanent middle cerebral artery occlusion and infarct size, brain gliosis, and brain and plasma cytokine profiles were analyzed. Chronic infection increased the infarct size in aged but not in young mice at 24 h. Aged, ischemic mice showed altered plasma and brain cytokine responses, while the lesion size correlated with plasma prestroke levels of RANTES. Moreover, the old, infected mice exhibited significantly increased neutrophil recruitment and upregulation of both plasma interleukin‐17α and tumor necrosis factor‐α levels. Neither age nor infection status alone or in combination altered the ischemia‐induced brain microgliosis. Our results show that chronic peripheral infection in aged animals renders the brain more vulnerable to ischemic insults, possibly by increasing the invasion of neutrophils and altering the inflammation status in the blood and brain. Understanding the interactions between age and infections is crucial for developing a better therapeutic regimen for ischemic stroke and when modeling it as a disease of the elderly. 相似文献
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Farzana Latif Ansari Abdul Wadood Ahsan Ullah Fatima Iftikhar 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):151-156
In continuation of our previous study on the urease inhibition by a number of chalcones, 2,3-dihydro-1,5-benzothiazepines and 2,3,4,5-tetrahydro-1,5-benzothiazepines, FlexX docking has been exploited to get a deeper insight into the mechanism of their inhibitory action. A comparison of the IC50 values of the active compounds reveals that, of the three classes of compounds studied, 2,3-dihydro-1,5-benzothiazepines were the most potent urease inhibitors. An in silico examination of these compounds showed that the activity is related to the interaction of ligand with the nickel metallocentre, its interaction with two amino acid residues, Asp224 and Cys322, in addition to the orientation of rings A and B in the catalytic core of the enzyme. The most active compound 2,3-dihydro-1,5-benzothiazepine (4) anchor tightly through a network of interactions with Ni701 and Ni702. This includes a number of hydrogen bonds and hydrophobic contacts with the amino acid residues in its vicinity. For their reduced analogs, the difference in the activity of different diastereomers has been observed to be configuration-dependent. This may be ascribed mainly to the difference in the orientation of ring B of the two stereoisomers and the extent of their interaction with Asp224 and Cys322 present in the catalytic core of the enzyme. 相似文献
160.
Chamaida Plasencia Dora Pascual-Salcedo Sara García-Carazo Leticia Lojo Laura Nu?o Alejandro Villalba Diana Peiteado Florencia Arribas Jesus Díez Maria Teresa López-Casla Emilio Martín-Mola Alejandro Balsa 《Arthritis research & therapy》2013,15(4):R79