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61.
62.
Whitehead TA Chevalier A Song Y Dreyfus C Fleishman SJ De Mattos C Myers CA Kamisetty H Blair P Wilson IA Baker D 《Nature biotechnology》2012,30(6):543-548
We show that comprehensive sequence-function maps obtained by deep sequencing can be used to reprogram interaction specificity and to leapfrog over bottlenecks in affinity maturation by combining many individually small contributions not detectable in conventional approaches. We use this approach to optimize two computationally designed inhibitors against H1N1 influenza hemagglutinin and, in both cases, obtain variants with subnanomolar binding affinity. The most potent of these, a 51-residue protein, is broadly cross-reactive against all influenza group 1 hemagglutinins, including human H2, and neutralizes H1N1 viruses with a potency that rivals that of several human monoclonal antibodies, demonstrating that computational design followed by comprehensive energy landscape mapping can generate proteins with potential therapeutic utility. 相似文献
63.
JC Lindow N Borochoff-Porte AP Durbin SS Whitehead KA Fimlaid JY Bunn BD Kirkpatrick 《PLoS neglected tropical diseases》2012,6(7):e1742
The four dengue virus serotypes (DENV-1-DENV-4) have a large impact on global health, causing 50-100 million cases of dengue fever annually. Herein, we describe the first kinetic T cell response to a low-dose DENV-1 vaccination study (10 PFU) in humans. Using flow cytometry, we found that proinflammatory cytokines, IFNγ, TNFα, and IL-2, were generated by DENV-1-specific CD4(+) cells 21 days post-DENV-1 exposure, and their production continued through the latest time-point, day 42 (p<0.0001 for all cytokines). No statistically significant changes were observed at any time-points for IL-10 (p = 0.19), a regulatory cytokine, indicating that the response to DENV-1 was primarily proinflammatory in nature. We also observed little T cell cross-reactivity to the other 3 DENV serotypes. The percentage of multifunctional T cells (T cells making ≥ 2 cytokines simultaneously) increased with time post-DENV-1 exposure (p<0.0001). The presence of multifunctional T cells together with neutralizing antibody data suggest that the immune response generated to the vaccine may be protective. This work provides an initial framework for defining primary T cell responses to each DENV serotype and will enhance the evaluation of a tetravalent DENV vaccine. 相似文献
64.
Stephanie Venn-Watson Lance Garrison Jenny Litz Erin Fougeres Blair Mase Gina Rappucci Elizabeth Stratton Ruth Carmichael Daniel Odell Delphine Shannon Steve Shippee Suzanne Smith Lydia Staggs Mandy Tumlin Heidi Whitehead Teri Rowles 《PloS one》2015,10(2)
A multi-year unusual mortality event (UME) involving primarily common bottlenose dolphins (Tursiops truncates) was declared in the northern Gulf of Mexico (GoM) with an initial start date of February 2010 and remains ongoing as of August 2014. To examine potential changing characteristics of the UME over time, we compared the number and demographics of dolphin strandings from January 2010 through June 2013 across the entire GoM as well as against baseline (1990-2009) GoM stranding patterns. Years 2010 and 2011 had the highest annual number of stranded dolphins since Louisiana’s record began, and 2011 was one of the years with the highest strandings for both Mississippi and Alabama. Statewide, annual numbers of stranded dolphins were not elevated for GoM coasts of Florida or Texas during the UME period. Demographic, spatial, and temporal clusters identified within this UME included increased strandings in northern coastal Louisiana and Mississippi (March-May 2010); Barataria Bay, Louisiana (August 2010-December 2011); Mississippi and Alabama (2011, including a high prevalence and number of stranded perinates); and multiple GoM states during early 2013. While the causes of the GoM UME have not been determined, the location and magnitude of dolphin strandings during and the year following the 2010 Deepwater Horizon oil spill, including the Barataria Bay cluster from August 2010 to December 2011, overlap in time and space with locations that received heavy and prolonged oiling. There are, however, multiple known causes of previous GoM dolphin UMEs, including brevetoxicosis and dolphin morbillivirus. Additionally, increased dolphin strandings occurred in northern Louisiana and Mississippi before the Deepwater Horizon oil spill. Identification of spatial, temporal, and demographic clusters within the UME suggest that this mortality event may involve different contributing factors varying by location, time, and bottlenose dolphin populations that will be better discerned by incorporating diagnostic information, including histopathology. 相似文献
65.
Stephanie Venn-Watson Kathleen M. Colegrove Jenny Litz Michael Kinsel Karen Terio Jeremiah Saliki Spencer Fire Ruth Carmichael Connie Chevis Wendy Hatchett Jonathan Pitchford Mandy Tumlin Cara Field Suzanne Smith Ruth Ewing Deborah Fauquier Gretchen Lovewell Heidi Whitehead David Rotstein Wayne McFee Erin Fougeres Teri Rowles 《PloS one》2015,10(5)
A northern Gulf of Mexico (GoM) cetacean unusual mortality event (UME) involving primarily bottlenose dolphins (Tursiops truncatus) in Louisiana, Mississippi, and Alabama began in February 2010 and continued into 2014. Overlapping in time and space with this UME was the Deepwater Horizon (DWH) oil spill, which was proposed as a contributing cause of adrenal disease, lung disease, and poor health in live dolphins examined during 2011 in Barataria Bay, Louisiana. To assess potential contributing factors and causes of deaths for stranded UME dolphins from June 2010 through December 2012, lung and adrenal gland tissues were histologically evaluated from 46 fresh dead non-perinatal carcasses that stranded in Louisiana (including 22 from Barataria Bay), Mississippi, and Alabama. UME dolphins were tested for evidence of biotoxicosis, morbillivirus infection, and brucellosis. Results were compared to up to 106 fresh dead stranded dolphins from outside the UME area or prior to the DWH spill. UME dolphins were more likely to have primary bacterial pneumonia (22% compared to 2% in non-UME dolphins, P = .003) and thin adrenal cortices (33% compared to 7% in non-UME dolphins, P = .003). In 70% of UME dolphins with primary bacterial pneumonia, the condition either caused or contributed significantly to death. Brucellosis and morbillivirus infections were detected in 7% and 11% of UME dolphins, respectively, and biotoxin levels were low or below the detection limit, indicating that these were not primary causes of the current UME. The rare, life-threatening, and chronic adrenal gland and lung diseases identified in stranded UME dolphins are consistent with exposure to petroleum compounds as seen in other mammals. Exposure of dolphins to elevated petroleum compounds present in coastal GoM waters during and after the DWH oil spill is proposed as a cause of adrenal and lung disease and as a contributor to increased dolphin deaths. 相似文献
66.
Cushing TD Baichwal V Berry K Billedeau R Bordunov V Broka C Browner MF Cardozo M Cheng P Clark D Dalrymple S DeGraffenreid M Gill A Hao X Hawley RC He X Labadie SS Labelle M Lehel C Lu PP McIntosh J Miao S Parast C Shin Y Sjogren EB Smith ML Talamas FX Tonn G Walker KM Walker NP Wesche H Whitehead C Wright M Jaen JC 《Bioorganic & medicinal chemistry letters》2011,21(1):423-426
A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKβ. In this Letter we document our efforts at further optimization of this series, culminating in 2 with submicromolar potency in a HWB assay and efficacy in a CIA mouse model. 相似文献
67.
Background
Variation in gene expression is extensive among tissues, individuals, strains, populations and species. The interactions among these sources of variation are relevant for physiological studies such as disease or toxic stress; for example, it is common for pathologies such as cancer, heart failure and metabolic disease to be associated with changes in tissue-specific gene expression or changes in metabolic gene expression. But how conserved these differences are among outbred individuals and among populations has not been well documented. To address this we examined the expression of a selected suite of 192 metabolic genes in brain, heart and liver in three populations of the teleost fish Fundulus heteroclitus using a highly replicated experimental design. 相似文献68.
Smith J.J.B.; Mitchell B.K.; Rolseth B.M.; Whitehead A.T.; Albert P.J. 《Chemical senses》1990,15(3):253-270
A set of programs is described for the digitization and analysisof electrophysiological recordings in which the nerve impulsesfrom several different cells may be present. Although they weredesigned for analysis of data from insect taste sensilla, theymay be applicable to other multi-unit preparations, and areavailable free from the authors. The programs run on standardMS-DOS compatible microcomputers, using a readily availableanalog-to-digital plug-in board. They are modular,and break the analysis into several stages, each of which maybe applied to many related files of data in a batchmode. Program design stresses the involvement of the user indecisions as to the effectiveness and accuracy of the analysisas it proceeds, as well as ease and efficiency of use. The programsuse many graphics screens in color, and are controlled by keyboard-or mouse-operated menus; however, they can also be controlledby command-line parameters for standard or repetitive input. 相似文献
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70.
Mtgr1 is a transcriptional corepressor that is required for maintenance of the secretory cell lineage in the small intestine 下载免费PDF全文