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141.
Phytoextraction of trace elements by water hyacinth in contaminated area of gold mine tailing 总被引:1,自引:0,他引:1
Tamara E. Romanova Olga v. Shuvaeva Ludmila a. Belchenko 《International journal of phytoremediation》2016,18(2):190-194
The ability of water hyacinth (Eichhornia crassipes) to uptake Ag, Ba, Cd, Mo, and Pb from waters in gold mine tailing area was studied. All experiments were carried out in the field conditions without using of model system. Bioconcentration (BCF) and translocation factors (TF) as well as elements accumulation by plant in different points of tailings-impacted area were evaluated. It has been shown that water hyacinth demonstrates high ability to accumulate Mo, Pb, and Ba with BCF values 24,360 ± 3600, 18,800 ± 2800 and 10,040 ± 1400, respectively and is efficient in translocation of Mo and Cd. The general trend of the plant accumulation ability in relation to the studied elements corresponds to their concentration in the medium. As the distance from tailings increases, concentration of Ag, Ba and Pb in plant decreases more clearly than that of Cd, while the amount of Mo accumulated by plant doesn't drop significantly in accordance with its concentration in water. Under the conditions of the confluence of river Ur and drainage stream Ba and Ag can be considered as potential candidates for phytomining. 相似文献
142.
Shefali Setia Verma Jessica N. Cooke Bailey Anastasia Lucas Yuki Bradford James G. Linneman Michael A. Hauser Louis R. Pasquale Peggy L. Peissig Murray H. Brilliant Catherine A. McCarty Jonathan L. Haines Janey L. Wiggs Tamara R. Vrabec Gerard Tromp Marylyn D. Ritchie eMERGE Network NEIGHBOR Consortium 《PLoS genetics》2016,12(9)
Primary open angle glaucoma (POAG) is a complex disease and is one of the major leading causes of blindness worldwide. Genome-wide association studies have successfully identified several common variants associated with glaucoma; however, most of these variants only explain a small proportion of the genetic risk. Apart from the standard approach to identify main effects of variants across the genome, it is believed that gene-gene interactions can help elucidate part of the missing heritability by allowing for the test of interactions between genetic variants to mimic the complex nature of biology. To explain the etiology of glaucoma, we first performed a genome-wide association study (GWAS) on glaucoma case-control samples obtained from electronic medical records (EMR) to establish the utility of EMR data in detecting non-spurious and relevant associations; this analysis was aimed at confirming already known associations with glaucoma and validating the EMR derived glaucoma phenotype. Our findings from GWAS suggest consistent evidence of several known associations in POAG. We then performed an interaction analysis for variants found to be marginally associated with glaucoma (SNPs with main effect p-value <0.01) and observed interesting findings in the electronic MEdical Records and GEnomics Network (eMERGE) network dataset. Genes from the top epistatic interactions from eMERGE data (Likelihood Ratio Test i.e. LRT p-value <1e-05) were then tested for replication in the NEIGHBOR consortium dataset. To replicate our findings, we performed a gene-based SNP-SNP interaction analysis in NEIGHBOR and observed significant gene-gene interactions (p-value <0.001) among the top 17 gene-gene models identified in the discovery phase. Variants from gene-gene interaction analysis that we found to be associated with POAG explain 3.5% of additional genetic variance in eMERGE dataset above what is explained by the SNPs in genes that are replicated from previous GWAS studies (which was only 2.1% variance explained in eMERGE dataset); in the NEIGHBOR dataset, adding replicated SNPs from gene-gene interaction analysis explain 3.4% of total variance whereas GWAS SNPs alone explain only 2.8% of variance. Exploring gene-gene interactions may provide additional insights into many complex traits when explored in properly designed and powered association studies. 相似文献
143.
Timothée Poisot Benjamin Baiser Jennifer A. Dunne Sonia Kéfi François Massol Nicolas Mouquet Tamara N. Romanuk Daniel B. Stouffer Spencer A. Wood Dominique Gravel 《Ecography》2016,39(4):384-390
The study of ecological networks is severely limited by 1) the difficulty to access data, 2) the lack of a standardized way to link meta‐data with interactions, and 3) the disparity of formats in which ecological networks themselves are stored and represented. To overcome these limitations, we have designed a data specification for ecological networks. We implemented a database respecting this standard, and released an R package (rmangal) allowing users to programmatically access, curate, and deposit data on ecological interactions. In this article, we show how these tools, in conjunction with other frameworks for the programmatic manipulation of open ecological data, streamlines the analysis process and improves replicability and reproducibility of ecological network studies. 相似文献
144.
Fiona C. Lewis‐McDougall Prashant J. Ruchaya Eva Domenjo‐Vila Tze Shin Teoh Larissa Prata Beverley J. Cottle James E. Clark Prakash P. Punjabi Wael Awad Daniele Torella Tamara Tchkonia James L. Kirkland Georgina M. Ellison‐Hughes 《Aging cell》2019,18(3)
Aging leads to increased cellular senescence and is associated with decreased potency of tissue‐specific stem/progenitor cells. Here, we have done an extensive analysis of cardiac progenitor cells (CPCs) isolated from human subjects with cardiovascular disease, aged 32–86 years. In aged subjects (>70 years old), over half of CPCs are senescent (p16INK4A, SA‐β‐gal, DNA damage γH2AX, telomere length, senescence‐associated secretory phenotype [SASP]), unable to replicate, differentiate, regenerate or restore cardiac function following transplantation into the infarcted heart. SASP factors secreted by senescent CPCs renders otherwise healthy CPCs to senescence. Elimination of senescent CPCs using senolytics abrogates the SASP and its debilitative effect in vitro. Global elimination of senescent cells in aged mice (INK‐ATTAC or wild‐type mice treated with D + Q senolytics) in vivo activates resident CPCs and increased the number of small Ki67‐, EdU‐positive cardiomyocytes. Therapeutic approaches that eliminate senescent cells may alleviate cardiac deterioration with aging and restore the regenerative capacity of the heart. 相似文献
145.
Rodríguez-Castillo Tamara Estévez Edurne González-Ferreras Alexia María Barquín José 《Ecosystems》2019,22(4):892-911
Ecosystems - River ecosystem metabolism (REM) is a promising cost-effective measure of ecosystem functioning, as it integrates many different ecosystem processes and is affected by both rapid... 相似文献
146.
Jonathan M. Large Kristian Birchall Nathalie S. Bouloc Andy T. Merritt Ela Smiljanic-Hurley Denise J. Tsagris Mary C. Wheldon Keith H. Ansell Peter J. Coombs Catherine A. Kettleborough David Whalley Lindsay B. Stewart Paul W. Bowyer David A. Baker Simon A. Osborne 《Bioorganic & medicinal chemistry letters》2019,29(3):509-514
Development of a class of bicyclic inhibitors of the Plasmodium falciparum cyclic GMP-dependent protein kinase (PfPKG), starting from known compounds with activity against a related parasite PKG orthologue, is reported. Examination of key sub-structural elements led to new compounds with good levels of inhibitory activity against the recombinant kinase and in vitro activity against the parasite. Key examples were shown to possess encouraging in vitro ADME properties, and computational analysis provided valuable insight into the origins of the observed activity profiles. 相似文献
147.
148.
149.
Lee H Hubbert ML Osborne TF Woodford K Zerangue N Edwards PA 《The Journal of biological chemistry》2007,282(30):21653-21661
Fxralpha is known to regulate a variety of metabolic processes, including bile acid, cholesterol, and carbohydrate metabolism. In this study, we show direct evidence that Fxralpha is a key player in maintaining sulfate homeostasis. We identified and characterized the sodium/sulfate co-transporter (NaS-1; Slc13a1) as an Fxralpha target gene expressed in the kidney and intestine. Electromobility shift assays, chromatin immunoprecipitation, and promoter reporter studies identified a single functional Fxralpha response element in the second intron of the mouse Slc13a1 gene. Treatment of wild-type mice with GW4064, a synthetic Fxralpha agonist, induced Slc13a1 mRNA in the intestine and kidney. Slc13a1 mRNA was also induced in the kidney and intestine of wild-type, but not Fxralpha-/- mice, after treatment with the hepatotoxin alpha-naphthylisothiocyanate, which is known to result in elevated blood bile acid levels. Finally, we observed a decrease in Slc13a1 mRNA in the kidney and intestine of Fxralpha-/- mice and a corresponding increase in urinary excretion of free sulfates as compared with wild-type mice. These results demonstrate that mouse Slc13a1 is a novel Fxralpha target gene expressed in the kidney and intestine and that in the absence of Fxralpha, mice waste sulfate into the urine. Thus, Fxralpha is necessary for normal sulfate homeostasis in vivo. 相似文献
150.
Melov S Adlard PA Morten K Johnson F Golden TR Hinerfeld D Schilling B Mavros C Masters CL Volitakis I Li QX Laughton K Hubbard A Cherny RA Gibson B Bush AI 《PloS one》2007,2(6):e536
Age-related neurodegenerative disease has been mechanistically linked with mitochondrial dysfunction via damage from reactive oxygen species produced within the cell. We determined whether increased mitochondrial oxidative stress could modulate or regulate two of the key neurochemical hallmarks of Alzheimer's disease (AD): tau phosphorylation, and beta-amyloid deposition. Mice lacking superoxide dismutase 2 (SOD2) die within the first week of life, and develop a complex heterogeneous phenotype arising from mitochondrial dysfunction and oxidative stress. Treatment of these mice with catalytic antioxidants increases their lifespan and rescues the peripheral phenotypes, while uncovering central nervous system pathology. We examined sod2 null mice differentially treated with high and low doses of a catalytic antioxidant and observed striking elevations in the levels of tau phosphorylation (at Ser-396 and other phospho-epitopes of tau) in the low-dose antioxidant treated mice at AD-associated residues. This hyperphosphorylation of tau was prevented with an increased dose of the antioxidant, previously reported to be sufficient to prevent neuropathology. We then genetically combined a well-characterized mouse model of AD (Tg2576) with heterozygous sod2 knockout mice to study the interactions between mitochondrial oxidative stress and cerebral Ass load. We found that mitochondrial SOD2 deficiency exacerbates amyloid burden and significantly reduces metal levels in the brain, while increasing levels of Ser-396 phosphorylated tau. These findings mechanistically link mitochondrial oxidative stress with the pathological features of AD. 相似文献