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The present study was designed to compare the effects of nano-selenium and of sodium selenite on the chemotactic and respiratory burst activities of neutrophils in sheep. Fifteen sheep were randomly divided into three groups. Groups 1 and 2 received selenium nanoparticles (1 mg/kg) or sodium selenite (1 mg/kg) orally, respectively, for ten consecutive days, and the third group was considered as the control. To determine the chemotactic and respiratory burst activities of the neutrophils, the leading front assay and the NBT test were used on heparinized blood samples that were collected at different intervals (days 0, 10th, 20th, and 30th). The results obtained showed that the chemotactic activities in groups 1 and 2 increased significantly on the 10th, 20th, and 30th day, compared to day 0, and on the 20th day in comparison with the 10th day, while in group 2, there was a significant decrease on the 30th day compared to the 20th day. The chemotactic activities in group 1 were significantly higher than in group 2 on the 10th day and in the control group on the 10th, 20th, and 30th day, but the chemotactic activities in group 2 were significantly higher than those in the control group only on the 20th day. On the 30th day into the experiment, the respiratory bursts in groups 1 and 2 were significantly stronger in comparison with those at day 0. Overall, nano-selenium increased the chemotactic and respiratory burst activities more significantly than sodium selenite, which is suggestive of a stronger stimulatory effect of the Se nanoparticles on intracellular activities.  相似文献   
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We report a multitechnique study of structural organization and molecular mobility for soy glycinin at a low moisture content (<30% w/w) and relate these to its glass-to-rubber transition. Small-angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy are used to probe structure and mobility on different length and time scales. NMR (approximately 10(-6) to 10(-3) s) reveals transitions at a higher moisture content (>17%) than DSC or SAXS, which sample for much longer times (approximately 10 to 10(3) s) and where changes are detected at >13% water content at 20 degrees C. The mobility transitions are accompanied by small changes in unit-cell parameters and IR band intensities and are associated with the enhanced motion of the polypeptide backbone. This study shows how characteristic features of the ordered regions of the protein (probed by SAXS and FTIR) and mobile segments (probed by NMR and DSC) can be separately monitored and integrated within a mobility transformation framework.  相似文献   
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DNA‐assisted proteomics technologies enable ultra‐sensitive measurements in multiplex format using DNA‐barcoded affinity reagents. Although numerous antibodies are available, nowadays targeting nearly the complete human proteome, the majority is not accessible at the quantity, concentration, or purity recommended for most bio‐conjugation protocols. Here, we introduce a magnetic bead‐assisted DNA‐barcoding approach, applicable for several antibodies in parallel, as well as reducing required reagents quantities up to a thousand‐fold. The success of DNA‐barcoding and retained functionality of antibodies were demonstrated in sandwich immunoassays and standard quantitative Immuno‐PCR assays. Specific DNA‐barcoding of antibodies for multiplex applications was presented on suspension bead arrays with read‐out on a massively parallel sequencing platform in a procedure denoted Immuno‐Sequencing. Conclusively, human plasma samples were analyzed to indicate the functionality of barcoded antibodies in intended proteomics applications.  相似文献   
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ATAD2, a remarkably conserved, yet poorly characterized factor is found upregulated and associated with poor prognosis in a variety of independent cancers in human. Studies conducted on the yeast Saccharomyces cerevisiae ATAD2 homologue, Yta7, are now indicating that the members of this family may primarily be regulators of chromatin dynamics and that their action on gene expression could only be one facet of their general activity. In this review, we present an overview of the literature on Yta7 and discuss the possibility of translating these findings into other organisms to further define the involvement of ATAD2 and other members of its family in regulating chromatin structure and function both in normal and pathological situations.  相似文献   
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Mnt is a Max-interacting protein that can antagonize the activities of Myc oncoproteins in cultured cells. Mnt null mice die soon after birth, but conditional deletion of Mnt in breast epithelium leads to tumor formation. These and related data suggest that Mnt functions as a tumor suppressor. Here we show that conditional deletion of Mnt in T cells leads to tumor formation but also causes inflammatory disease. Deletion of Mnt caused increased apoptosis of thymic T cells and interfered with T-cell development yet led to spleen, liver, and lymph node enlargement. The proportion of T cells in the spleen and lymph nodes was reduced, and the numbers of cells in non-T-cell immune cell populations were elevated. The disruption of immune homeostasis is linked to a strong skewing toward production of T-helper 1 (Th1) cytokines and enhanced proliferation of activated Mnt-deficient CD4+ T cells. Consistent with Th1 polarization in vivo, extensive intestinal inflammation and liver necrosis developed. Finally, most mice lacking Mnt in T cells ultimately succumbed to T-cell lymphoma. These results strengthen the argument that Mnt functions as a tumor suppressor and reveal a critical and surprising role for Mnt in the regulation of T-cell development and in T-cell-dependent immune homeostasis.  相似文献   
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The major barrier to effective cancer therapy is the presence of genetic and phenotypic heterogeneity within cancer cell populations that provides a reservoir of therapeutically resistant cells. As the degree of heterogeneity present within tumours will be proportional to tumour burden, the development of rapid, robust, accurate and sensitive biomarkers for cancer progression that could detect clinically occult disease before substantial heterogeneity develops would provide a major therapeutic benefit. Here, we explore the application of chromatin conformation capture technology to generate a diagnostic epigenetic barcode for melanoma. The results indicate that binary states from chromatin conformations at 15 loci within five genes can be used to provide rapid, non‐invasive multivariate test for the presence of melanoma using as little as 200 μl of patient blood.  相似文献   
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Behavioral evidence suggests that instrumental conditioning is governed by two forms of action control: a goal-directed and a habit learning process. Model-based reinforcement learning (RL) has been argued to underlie the goal-directed process; however, the way in which it interacts with habits and the structure of the habitual process has remained unclear. According to a flat architecture, the habitual process corresponds to model-free RL, and its interaction with the goal-directed process is coordinated by an external arbitration mechanism. Alternatively, the interaction between these systems has recently been argued to be hierarchical, such that the formation of action sequences underlies habit learning and a goal-directed process selects between goal-directed actions and habitual sequences of actions to reach the goal. Here we used a two-stage decision-making task to test predictions from these accounts. The hierarchical account predicts that, because they are tied to each other as an action sequence, selecting a habitual action in the first stage will be followed by a habitual action in the second stage, whereas the flat account predicts that the statuses of the first and second stage actions are independent of each other. We found, based on subjects'' choices and reaction times, that human subjects combined single actions to build action sequences and that the formation of such action sequences was sufficient to explain habitual actions. Furthermore, based on Bayesian model comparison, a family of hierarchical RL models, assuming a hierarchical interaction between habit and goal-directed processes, provided a better fit of the subjects'' behavior than a family of flat models. Although these findings do not rule out all possible model-free accounts of instrumental conditioning, they do show such accounts are not necessary to explain habitual actions and provide a new basis for understanding how goal-directed and habitual action control interact.  相似文献   
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