Given continuous development in society and the economy, obesity has become a global epidemic, arousing great concern. In addition to genetic and dietary factors, exposure to environmental chemicals is associated with the occurrence and development of obesity. Current research has indicated that some chemicals with endocrine-disrupting effects can affect lipid metabolism , causing elevated lipid storage.
View Article and Find Full Text PDFUnderstanding the geochemical cycle of mercury (Hg) in the high-altitude Tibetan Plateau is of great value for studying the long-range transport of Hg. Herein, speciation and isotopic compositions of Hg in the muscle and feathers of upland buzzards (Buteo hemilasius) were studied to trace the terrestrial transformation of Hg in the Tibetan Plateau. Very low Hg content and relatively low δHg values (feather: -0.
View Article and Find Full Text PDFEnvironmental distribution and concentration of tetrabromobisphenol A bis- (2-hydroxyethyl) ether (TBBPA-DHEE) and tetrabromobisphenol A mono- (hydroxyethyl) ether (TBBPA-MHEE), are obscure due to the lack of available analytical methods. Here two novel immunoassays were established to systematically investigate their distributions in Taizhou, Eastern China. Five monoclonal antibodies against pollutants were generated with two designed haptens through animal immunization.
View Article and Find Full Text PDFUnderstanding the distribution and sources of mercury (Hg) in the Tibetan Plateau is of great value to study the long-range transport of Hg. Herein, the total Hg (THg) concentrations and the isotopic compositions of mosses, conifer needles, and surface soils collected from both slopes of the Shergyla Mountain of Tibetan Plateau were analyzed. The contents of THg in samples (except mosses on the eastern slope) were significantly positively correlated with altitude in both the western and eastern slopes, possibly caused by topographic factors.
View Article and Find Full Text PDFCoastal sediments are a major sink of the global mercury (Hg) biogeochemical cycle, bridging terrestrial Hg migration to the open ocean. It is thus of substantial interest to quantify the Hg contributors to coastal sediments and the extents to which the Hg sequestered into coastal sediments affects the ocean. Here, we measured concentrations and isotope compositions of Hg in Chinese coastal sediments and found that estuary sediments had distinctly higher δHg and lower ΔHg values than marine sediments.
View Article and Find Full Text PDFJ Environ Sci (China)
June 2018
N6-methyladenosine (m6A) RNA methylation is the most abundant modification on mRNAs and plays important roles in various biological processes. The formation of m6A is catalyzed by a methyltransferase complex including methyltransferase-like 3 (METTL3) as a key factor. However, the in vivo functions of METTL3 and m6A modification in mammalian development remain unclear.
View Article and Find Full Text PDFTo trace the most concerned bioavailable mercury (Hg) in aquatic environment, fish samples were collected from three typical regions in China, including 3 rivers and 1 lake in the Tibetan Plateau (TP, a high altitude background region with strong solar radiation), the Three Gorges Reservoir (TGR, the largest artificial freshwater reservoir in China), and the Chinese Bohai Sea (CBS, a heavily human-impacted semi-enclosed sea). The Hg isotopic compositions in fish muscles were analyzed. The results showed that anthropogenic emissions were the main sources of Hg in fish from TGR and CBS because of the observed negative δHg and positive ΔHg in these two regions (TGR, δHg: - 0.
View Article and Find Full Text PDFInorganic divalent mercury complexes (Hg) and monomethylmercury complexes (MeHg) are the main mercury species in aquatic systems and their toxicity to aquatic organisms is of great concern. Tetrahymena is a type of unicellular eukaryotic protozoa located at the bottom of food chain that plays a fundamental role in the biomagnification of mercury. In this work, the dynamic accumulation properties, toxicological characteristics and mechanisms of Hg and MeHg in five Tetrahymena species were evaluated in detail.
View Article and Find Full Text PDFIt is a great challenge to monitor the physical and chemical transformation of nanoparticles at environmentally relevant concentration levels, mainly because the commonly used techniques like dynamic light scattering and transmission electron microscopy are unable to characterize and quantify trace level nanoparticles in complex matrices. Herein, we demonstrate the on-line coupled system of hollow fiber flow field-flow fractionation (HF5), minicolumn concentration, and inductively coupled plasma mass spectrometry (ICPMS) detection as an efficient approach to study the aggregation and chemical transformation of silver nanoparticles (AgNPs) and ionic Ag species in the aqueous environment at ng/mL levels. Taking advantage of the in-line dialysis of HF5, the selective capture of Ag(I) species by the resin in minicolumn, and the high selectivity and sensitivity of ICPMS detection, we recorded the aggregation of 10 ng/mL AgNPs in complex matrices (e.
View Article and Find Full Text PDFUnderstanding the mechanism of nanosilver-dependent antibacterial activity against microorganisms helps optimize the design and usage of the related nanomaterials. In this study, we prepared four kinds of 10 nm-sized silver nanoparticles (AgNPs) with dictated surface chemistry by capping different ligands, including citrate, mercaptopropionic acid, mercaptohexanoic acid, and mercaptopropionic sulfonic acid. Their surface-dependent chemistry and antibacterial activities were investigated.
View Article and Find Full Text PDF5-methylcytosine (mC) is a post-transcriptional RNA modification identified in both stable and highly abundant tRNAs and rRNAs, and in mRNAs. However, its regulatory role in mRNA metabolism is still largely unknown. Here, we reveal that mC modification is enriched in CG-rich regions and in regions immediately downstream of translation initiation sites and has conserved, tissue-specific and dynamic features across mammalian transcriptomes.
View Article and Find Full Text PDFAccurate characterization, quantification, and identification of nanoparticles (NPs) are essential to fully understand the environmental processes and effects of NPs. Herein, the elemental mass size distribution (EMSD), which measures particle size, mass, and composition, is proposed for the direct size characterization, mass quantification, and composition identification of trace NPs in complex matrixes. A one-step method for the rapid measurement of EMSDs in 8 min was developed through the online coupling of size-exclusion chromatography (SEC) with inductively coupled plasma mass spectrometry (ICP-MS).
View Article and Find Full Text PDFA Ag monolayer facilitates the deposition of isolated Pd atoms rather than continuous ones on ultrathin Au nanowires. During the hydrogenation of nitrophenol and the electrooxidation of ethanol, these two groups of Pd atoms show distinctive but geometry-dependent catalytic activity. This new atomic geometry maneuvering strategy is ready for the atomically precise design of nanocatalysts.
View Article and Find Full Text PDFTetrabromobisphenol-A/S (TBBPA/S) analogs have raised substantial concern because of their adverse effects and potential bioaccumulative properties, such as TBBPA bis(allyl ether) (TBBPA-BAE) and TBBPA bis(2,3-dibromopropyl ether) (TBBPA-BDBPE). In this study, a comprehensive method for simultaneous determination of TBBPA/S and nine novel analogs, including TBBPA-BAE, TBBPA-BDBPE, TBBPS-BDBPE, TBBPA mono(allyl ether) (TBBPA-MAE), TBBPA mono(2-bromoallyl ether) (TBBPA-MBAE), TBBPA mono(2,3-dibromopropyl ether) (TBBPA-MDBPE), TBBPS-MAE, TBBPS-MBAE, and TBBPS-MDBPE in biological samples was developed. The distribution patterns and trophic transfer properties of TBBPA/S and analogs in various biological samples collected from the Chinese Bohai Sea were then studied in detail.
View Article and Find Full Text PDFThe regulatory role of N(6)-methyladenosine (m(6)A) and its nuclear binding protein YTHDC1 in pre-mRNA splicing remains an enigma. Here we show that YTHDC1 promotes exon inclusion in targeted mRNAs through recruiting pre-mRNA splicing factor SRSF3 (SRp20) while blocking SRSF10 (SRp38) mRNA binding. Transcriptome assay with PAR-CLIP-seq analysis revealed that YTHDC1-regulated exon-inclusion patterns were similar to those of SRSF3 but opposite of SRSF10.
View Article and Find Full Text PDFThe intertransformation of silver nanoparticles (AgNPs) and ionic silver (Ag(I)) in the environment determines their transport, uptake, and toxicity, demanding methods to simultaneously separate and quantify AgNPs and Ag(I). For the first time, hollow fiber flow field-flow fractionation (HF5) and minicolumn concentration were on-line coupled together with multiple detectors (including UV-vis spectrometry, dynamic light scattering, and inductively coupled plasma mass spectrometry) for full spectrum separation, characterization, and quantification of various Ag(I) species (i.e.
View Article and Find Full Text PDFIdentification of novel brominated contaminants in the environment, especially the derivatives and byproducts of brominated flame retardants (BFRs), has become a wide concern because of their adverse effects on human health. Herein, we qualitatively and quantitatively identified three byproducts of tetrabromobisphenol-S bis(2,3-dibromopropyl ether) (TBBPS-BDBPE), including TBBPS mono(allyl ether) (TBBPS-MAE), TBBPS mono(2-bromoallyl ether) (TBBPS-MBAE) and TBBPS mono(2,3-dibromopropyl ether) (TBBPS-MDBPE) as novel brominated contaminants. Meanwhile, the mass spectra and analytical method for determination of TBBPS-BDBPE byproducts were presented for the first time.
View Article and Find Full Text PDFIn this report, we propose and demonstrate the fabrication of a highly-specific SERS substrate, which was achieved by the co-precipitation of functional materials, such as nanosorbents and nanocatalysts, into Ag nanoporous films. Based on the nanostructures developed, we performed the ultrasensitive detection of arsenic ions by SERS and monitored the catalyzed reactions using real-time SERS.
View Article and Find Full Text PDFThe exposure of millions of people to unsafe levels of arsenite (AsIII) and arsenate (AsV) in drinking waters calls for the development of low-cost methods for on-site monitoring these two arsenic species in waters. Herein, for the first time, tetradecyl (trihexyl) phosphonium chloride ionic liquid was found to selectively bind with AsIII via extended X-ray absorption fine structure (EXAFS) analysis. Based on the finding, an AsIII-specific probe was developed by modifying gold nanoparticles with the ionic liquid.
View Article and Find Full Text PDFA total of 220 surface sediments and eight sediment cores were analyzed to study the distribution and transport of Hg in Chinese marginal seas. Spatial distribution showed a general offshore decreasing trend towards the outer continental shelf. Vertical profiles of sediment cores displayed a general increasing trend from bottom to surface layers.
View Article and Find Full Text PDFSeafood samples were collected from Dalian, China to study the accumulation and distribution characteristics of short chain chlorinated paraffins (SCCPs) by GC/ECNI-LRMS. Sum of SCCPs (dry weight) were in the range of 77-8 250 ng.g-1, with the lowest value in Scapharca subcrenata and highest concentration in Neptunea cumingi.
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