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991.
Marc Woodbury-Smith Andrew D. Paterson Bhooma Thiruvahindrapduram Anath C. Lionel Christian R. Marshall Daniele Merico Bridget A. Fernandez Eric Duku James S. Sutcliffe Irene O’Conner Christina Chrysler Ann Thompson Barbara Kellam Kristiina Tammimies Susan Walker Ryan K. C. Yuen Mohammed Uddin Jennifer L. Howe Morgan Parlier Kathy Whitten Peter Szatmari Veronica J. Vieland Joseph Piven Stephen W. Scherer 《Human genetics》2015,134(2):191-201
992.
Blake A. Grisham Clint W. Boal David A. Haukos Dawn M. Davis Kathy K. Boydston Charles Dixon Willard R. Heck 《PloS one》2013,8(7)
The Southern High Plains is anticipated to experience significant changes in temperature and precipitation due to climate change. These changes may influence the lesser prairie-chicken (Tympanuchus pallidicinctus) in positive or negative ways. We assessed the potential changes in clutch size, incubation start date, and nest survival for lesser prairie-chickens for the years 2050 and 2080 based on modeled predictions of climate change and reproductive data for lesser prairie-chickens from 2001–2011 on the Southern High Plains of Texas and New Mexico. We developed 9 a priori models to assess the relationship between reproductive parameters and biologically relevant weather conditions. We selected weather variable(s) with the most model support and then obtained future predicted values from climatewizard.org. We conducted 1,000 simulations using each reproductive parameter’s linear equation obtained from regression calculations, and the future predicted value for each weather variable to predict future reproductive parameter values for lesser prairie-chickens. There was a high degree of model uncertainty for each reproductive value. Winter temperature had the greatest effect size for all three parameters, suggesting a negative relationship between above-average winter temperature and reproductive output. The above-average winter temperatures are correlated to La Niña events, which negatively affect lesser prairie-chickens through resulting drought conditions. By 2050 and 2080, nest survival was predicted to be below levels considered viable for population persistence; however, our assessment did not consider annual survival of adults, chick survival, or the positive benefit of habitat management and conservation, which may ultimately offset the potentially negative effect of drought on nest survival. 相似文献
993.
994.
Transfer of the catabolic plasmid RP4::Tn4371 to indigenous soil bacteria and its effect on respiration and biphenyl breakdown 总被引:1,自引:0,他引:1
Helene De Rore Kathy Demolder Kurt De Wilde Eva Top Frans Houwen Willy Verstraete 《FEMS microbiology ecology》1994,15(1-2):71-77
Abstract The catabolic plasmid RP4::Tn 4371 , containing the genes for biphenyl and 4-chlorobiphenyl catabolism, was transferred from Enterobacter agglomerans DMK3 to indigenous bacteria in biphenyl amended sandy soil, although the donor survived for only 3 days. Proliferation of transconjugants above a detectable level required presence of the concomitant pollutant biphenyl. Different Gram-negative bacterial species, tentatively identified as Pseudomonas chlororaphis, Pseudomonas corrugata and Comamonas sp., had taken up the plasmid and were able to express the biphenyl degradation genes. These genera have, until now, not been reported to express the biphenyl degradative genes. The soil had a high natural catabolic capacity for biphenyl. Notwithstanding this, out of 8 trials in which DMK3 was inoculated, 2 were found not to respond but 6 had an increased biphenyl degradation and concomitant increased oxygen consumption. The results indicate that seeding of RP4::Tn 4371 generates a variety of transconjugants and holds potential for increasing the soil biodegradation capacity towards chlorinated biphenyl analogues. 相似文献
995.
996.
The zebra finch (Taeniopygia guttata) has a large Z chromosome and highly condensed W chromosome. We used the random amplified polymorphic DNA (RAPD) polymerase
chain reaction (PCR) technique to isolate female-specific sequences ZBM1 and ZBM2. Southern blot hybridization to male and
female zebra finch genomic DNA suggested that these sequences were located on the W chromosome, although homologous sequences
appeared to be autosomal or Z-linked. Fluorescent in situ hybridization (FISH) using bacterial artificial chromosome (BAC)
clones corresponding to ZBM sequences showed hybridization to the whole W chromosome, suggesting that the BACs encode sequences
that are repeated across the entire W chromosome. Based on the sequencing of a ZBM repetitive sequence and Z chromosome derived
BAC clones, we demonstrate a random distribution of repeat sequences that are specific to the W chromosome or encoded by both
Z and W. The positions of ZW-common repeat sequences mapped to a noncoding region of a Z chromosome BAC clone containing the
CHD1Z gene. The apparent lineage-specificity of W chromosome repeat sequences in passerines and galliform birds suggest that
the W chromosome had not differentiated well from the Z at the time of divergence of these lineages.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
The animal egg is a unique quiescent cell, prepackaged with maternal mRNAs and proteins that have functions in early development. Rapid, transient signaling at fertilization alters egg physiology, resulting in Ca2+ release from the endoplasmic reticulum (ER) and cytoplasmic alkalinization. These events trigger the zygote developmental program through initiation of DNA synthesis and entry into mitosis. Post-translational modifications of maternal proteins are responsible for the spatio-temporal regulation that orchestrates egg activation. We used functional proteomics to identify the candidate maternal proteins involved in egg activation and early development. As the first step of this analysis, we present the data on the baseline maternal proteome, in particular, on proteins exhibiting changes in abundance and in phosphorylation state upon egg activation. We identify 94 proteins that were stable, reproducibly displayed a shift in isoelectric point, or changed in relative abundance at specific times after activation. The identities of these proteins were determined by quadrupole time-of-flight tandem mass spectrometry. The set of the most dynamic proteins appear to be enriched in intermediary metabolism proteins, cytoskeletal proteins, gamete associated proteins and proteins that have Ca2+ mediated activities. 相似文献
998.
International Comparison of Clinical, Bovine, and Environmental Escherichia coli O157 Isolates on the Basis of Shiga Toxin-Encoding Bacteriophage Insertion Site Genotypes
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Joshua H. Whitworth Narelle Fegan Jasmin Keller Kari S. Gobius James L. Bono Douglas R. Call Dale D. Hancock Thomas E. Besser 《Applied microbiology》2008,74(23):7447-7450
Escherichia coli O157:H7 genotypes in the bovine reservoir may differ in virulence. The proportion of clinical genotypes among cattle isolates was weakly (P = 0.054) related to the international incidence of E. coli O157:H7-associated hemolytic-uremic syndrome, varied among clinical isolates internationally, and also differed along the putative cattle-hamburger-clinical case transmission chain. 相似文献
999.
Evidence is emerging of a growing societal consensus about appropriate and inappropriate uses of genetic information. The Genetic Information Nondiscrimination Act of 2008 provides new legal protections to Americans by prohibiting the discriminatory use of genetic information by health insurers and employers. Additionally, the United States military recently created new policies for fair use of genetic information in the determination of benefits for servicemen and servicewomen leaving military service. Although critical issues remain, such as the potential for genetic information to be used to deny people other forms of insurance, and how the military will use genetic medicine overall, significant progress has been made. 相似文献
1000.
He Q Eko FO Lyn D Ananaba GA Bandea C Martinez J Joseph K Kellar K Black CM Igietseme JU 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(6):4037-4042
We investigated the hypothesis that the enhanced Ag-presenting function of IL-10-deficient dendritic cells (DCs) is related to specific immunoregulatory cytoskeletal molecules expressed when exposed to Ags. We analyzed the role of a prominent cytoskeletal protein, LEK1, in the immunoregulation of DC functions; specifically cytokine secretion, costimulatory molecule expression, and T cell activation against Chlamydia. Targeted knockdown of LEK1 expression using specific antisense oligonucleotides resulted in the rapid maturation of Chlamydia-exposed DCs as measured by FACS analysis of key activation markers (i.e., CD14, CD40, CD54, CD80, CD86, CD197, CD205, and MHC class II). The secretion of mostly Th1 cytokines and chemokines (IL-1a, IL-9, IL-12, MIP-1a, and GM-CSF but not IL-4 and IL-10) was also enhanced by blocking of LEK1. The function of LEK1 in DC regulation involves cytoskeletal changes, since the dynamics of expression of vimentin and actin, key proteins of the cellular cytoskeleton, were altered after exposure of LEK1 knockdown DCs to Chlamydia. Furthermore, targeted inhibition of LEK1 expression resulted in the enhancement of the immunostimulatory capacity of DCs for T cell activation against Chlamydia. Thus, LEK1 knockdown DCs activated immune T cells at least 10-fold over untreated DCs. These results suggest that the effect of IL-10 deficiency is mediated through LEK1-related events that lead to rapid maturation of DCs and acquisition of the capacity to activate an elevated T cell response. Targeted modulation of LEK1 expression provides a novel strategy for augmenting the immunostimulatory function of DCs for inducing an effective immunity against pathogens. 相似文献