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911.
Huifang Lv Wang Dong Zhi Cao Jihui Lin Yueling Ouyang Kangkang Guo Cunfa Li Yanming Zhang 《Journal of biosciences》2018,43(5):947-957
Classical swine fever (CSF) is a contagious disease with a high mortality rate and is caused by classical swine fever virus (CSFV). CSFV non-structural protein 4B (NS4B) plays a crucial role in CSFV replication and pathogenicity. However, precisely how NS4B exerts these functions remains unknown, especially as there are no reports relating to potential cellular partners of CSFV NS4B. Here, a yeast two-hybrid (Y2H) system was used to screen the cellular proteins interacting with NS4B from a porcine alveolar macrophage (PAM) cDNA library. The protein screen along with alignment using the NCBI database revealed 14 cellular proteins that interact with NS4B: DDX39B, COX7C, FTH1, MAVS, NR2F6, RPLP1, PSMC4, FGL2, MKRN1, RPL15, RPS3, RAB22A, TP53BP2 and TBK1. These proteins mostly relate to oxidoreductase activity, signal transduction, localization, biological regulation, catalytic activity, transport and metabolism by GO categories. Tank-binding kinase 1 (TBK1) was chosen for further confirmation. The NS4B-TBK1 interaction was further confirmed by subcellular co-location, co-immunoprecipitation and glutathione S-transferase pull-down assays. This study offers a theoretical foundation for further understanding of the diversity of NS4B functions in relation to viral infection and subsequent pathogenesis. 相似文献
912.
913.
Quantitative Proteomic Analysis of Biological Processes and Responses of the Bacterium Desulfovibrio desulfuricans ND132 upon Deletion of Its Mercury Methylation Genes 下载免费PDF全文
Chen Qian Hongmei Chen Alexander Johs Xia Lu Jing An Eric M. Pierce Jerry M. Parks Dwayne A. Elias Robert L. Hettich Baohua Gu 《Proteomics》2018,18(17)
Recent studies of microbial mercury (Hg) methylation revealed a key gene pair, hgcAB, which is essential for methylmercury (MeHg) production in the environment. However, many aspects of the mechanism and biological processes underlying Hg methylation, as well as any additional physiological functions of the hgcAB genes, remain unknown. Here, quantitative proteomics are used to identify changes in potential functional processes related to hgcAB gene deletion in the Hg‐methylating bacterium Desulfovibrio desulfuricans ND132. Global proteomics analyses indicate that the wild type and ΔhgcAB strains are similar with respect to the whole proteome and the identified number of proteins, but differ significantly in the abundance of specific proteins. The authors observe changes in the abundance of proteins related to the glycolysis pathway and one‐carbon metabolism, suggesting that the hgcAB gene pair is linked to carbon metabolism. Unexpectedly, the authors find that the deletion of hgcAB significantly impacts a range of metal transport proteins, specifically membrane efflux pumps such as those associated with heavy metal copper (Cu) export, leading to decreased Cu uptake in the ΔhgcAB mutant. This observation indicates possible linkages between this set of proteins and metal homeostasis in the cell. However, hgcAB gene expression is not induced by Hg, as evidenced by similarly low abundance of HgcA and HgcB proteins in the absence or presence of Hg (500 nm ). Taken together, these results suggest an apparent link between HgcAB, one‐carbon metabolism, and metal homeostasis, thereby providing insights for further exploration of biochemical mechanisms and biological functions of microbial Hg methylation. 相似文献
914.
Structural Engineering of Multishelled Hollow Carbon Nanostructures for High‐Performance Na‐Ion Battery Anode 下载免费PDF全文
De‐Shan Bin Yunming Li Yong‐Gang Sun Shu‐Yi Duan Yaxiang Lu Jianmin Ma An‐Min Cao Yong‐Sheng Hu Li‐Jun Wan 《Liver Transplantation》2018,8(26)
Hard carbon has long been considered the leading candidate for anode materials of Na‐ion batteries. Intensive research efforts have been carried out in the search of suitable carbon structure for an improved storage capability. Herein, an anode based on multishelled hollow carbon nanospheres, which are able to deliver an outstanding electrochemical performance with an extraordinary reversible capacity of 360 mAh g?1 at 30 mA g?1, is designed. An interesting dependence of the electrochemical properties on the multishelled structural features is identified: with an increase in the shell number of the model carbon materials, the sloping capacity in the charge/discharge curve remains almost unchanged while the plateau capacity continuously increases, suggesting an adsorption‐filling Na‐storage mechanism for the multishelled hollow hard carbon materials. The findings not only provide new perspective in the structural design of high‐performance anode materials, but also shed light on the complicated mechanism behind Na‐storage by hard carbon. 相似文献
915.
William J. Meurer Brigid Rowell Devin Brown Alexander Tsodikov Angela Fagerlin Steven A. Telian Laura Damschroder Lawrence C. An Lewis B. Morgenstern Laura Loudermilk Sandeep Vijan Kevin A. Kerber 《Trials》2018,19(1):697
Background
Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder, and accounts for 8% of individuals with moderate or severe dizziness. BPPV patients experience substantial inconveniences and disabilities during symptomatic periods. BPPV therapeutic processes – the Dix-Hallpike Test (DHT) and the Canalith Repositioning Maneuver (CRM) – have an evidence base that is at the clinical practice guideline level. The most commonly used CRM is the modified Epley maneuver. The DHT is the gold standard test for BPPV and the CRM is supported by numerous randomized controlled trials and systematic reviews. Despite this, BPPV care processes are underutilized.Methods/design
This is a stepped-wedge, randomized clinical trial of a multi-faceted educational and care-process-based intervention designed to improve the guideline-concordant care of patients with BPPV presenting to the emergency department (ED) with dizziness. The unit of randomization and target of intervention is the hospital. After an initial observation period, the six hospitals will undergo the intervention in five waves (two closely integrated hospitals will be paired). The order will be randomized. The primary endpoint is measured at the individual patient level, and is the presence of documentation of either the Dix-Hallpike Test or CRM. The secondary endpoints are referral to a health care provider qualified to treat dizziness for CRM and 90-day stroke rates following an ED dizziness visit. Formative evaluations are also performed to monitor and identify potential and actual influences on the progress and effectiveness of the implementation efforts.Discussion
If this study safely increases documentation of the DHT/CRM, this will be an important step in implementing the use of these evidenced-based processes of care. Positive results will support conducting larger-scale follow-up studies that assess patient outcomes. The data collection also enables evaluation of potential and actual influences on the progress and effectiveness of the implementation efforts.Trial registration
ClinicalTrials.gov, ID: NCT02809599. The record was first available to the public on 22 June 2016 prior to the enrollment of the first patients in October 2016.916.
917.
Martine Mostert An Caris Sabine Limbourg 《Flexible Services and Manufacturing Journal》2018,30(3):397-420
Freight transport planning is nowadays encouraged to align with environmental objectives. Among those, climate change is of particular interest for many countries. In its White Paper on Transport, the European Commission considers intermodal transport as a potential solution for reducing environmental impacts. In order to make good strategic transport decisions, realistic decision support models for freight transport networks must be developed, so that insights can be derived for the different stakeholders of the transportation chain. This research proposes a bi-objective mathematical formulation which takes into account economic and environmental objectives, on a road and intermodal network with three modes of transport (road, intermodal rail, and intermodal inland waterways), and in which economies of scale of intermodal transport can be considered. With this model better fitting reality, an application to the Belgian case study provides practical information on how flows, terminal types and locations vary depending on the chosen policy, on the integration or not of economies of scale, on costs or emissions modifications and on the number of terminals to locate. Results show that the chosen policy influences the terminal type and the intermodal market share. The study also highlights the interest of intermodal transport on short distances, and the risk of flow exchanges inside the intermodal market share, rather than between road and intermodal transport. 相似文献
918.
919.
Min Zhang Qingsheng Chen Peng Zhou Qiang Zhang Yanming Fang 《Plant Growth Regulation》2018,86(3):445-453
It has been suggested that vacuolar H+-ATPase (V-H+-ATPase) plays a pivotal role in salt stress, and salt stress could modulate the expression and enzyme activity of V-H+-ATPase. In this work, salt modulation of V-H+-ATPase and tonoplast fatty acid compositions were evaluated in two shrub willow clones differing in salt tolerance after 3, 6 and 12 days of treatment. The results showed that the activity of V-H+-ATPase was regulated in tissue and clone specifically under NaCl stress. In the leaves of salt-tolerant clone 2345, treatment with 100 mM NaCl increased V-H+-ATPase activity first and then decreased it at day 12, while V-H+-ATPase activity was stimulated in the roots by NaCl during the treatment time. In contrast, V-H+-ATPase activity reached the highest value at day 3 in the leaves of salt-sensitive clone 2367 and then it decreased. Accumulation of Na+ in the vacuole was observed in parallel with increase in V-H+-ATPase activity. Western blot and immunofluorescence analysis of V-H+-ATPase subunit E revealed that the protein content varied in parallel with V-H+-ATPase activity. Moreover, a decreased unsaturated fatty acids ratio to saturated ones together with an increased V-H+-ATPase activity was detected in the roots of salt-tolerant clone 2345 at day 12. Altogether, it suggested that the induction of V-H+-ATPase expression and increase in the saturation of tonoplast fatty acids as a homeostatic mechanism for shrub willow to cope with salt stress. 相似文献
920.
Inhalation of airborne fungi is known to cause respiratory illnesses such as allergies. However, the association between exposure and health outcomes remains largely unclear, in part due to lack of knowledge about fungal exposure in daily life. This study aims to introduce DNA-based methods such as high-throughput sequencing (HTS) and quantitative polymerase chain reaction (qPCR) to compare fungal microbiota and concentrations in indoor, outdoor, and personal air. Five sets of concurrent indoor, outdoor, and personal air samples were collected, each with duration of 4 days. Sequencing analysis revealed greater species richness in personal than indoor air for four out of the five sets, indicating that people are exposed to outdoor species that are not in indoor air. The personal–indoor (P/I) and personal–outdoor (P/O) ratios of total fungi were 1.2 and 0.15, respectively, suggesting that personal exposure to total fungi is better represented by indoor than outdoor concentrations. However, the ratios were taxon dependent, highlighting the complexity of generalizing personal exposure to the diverse kingdom Fungi. These results demonstrate that the HTS/qPCR method is useful for assessing taxon-specific fungal exposure, which might be difficult to achieve effectively using conventional, non-DNA-based techniques. 相似文献