Publications by authors named "Weiping Xu"

65 Publications

Simultaneous detection of tumor-related mRNA and miRNA in cancer cells with magnetic SERS nanotags.

Talanta 2021 Sep 24;232:122432. Epub 2021 Apr 24.

The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230001, China; Anhui Provincial Key Laboratory of Tumor Immunotherapy and Nutrition Therapy, Anhui, Hefei, 230001, China. Electronic address:

The design of simultaneous detection method has broad prospects for cancer diagnosis and prognosis. Herein, we reported a low cost and sensitive SERS sensing platform for simultaneous p21 mRNA and miRNA-21 detection based on duplex-specific nuclease signal amplification (DSNSA) plus multifunctional [email protected] magnetic nanoparticles ([email protected] MNPs). Here, [email protected] MNPs were used as a separation substrate, and [email protected] served as stable and ultrasensitive SERS nanotags. Firstly, [email protected] and [email protected] MNPs were attached to both ends of capture probe (CP) by covalent bonds. Under the assistance of the target p21 mRNA and miRNA-21, DNA (CP) of the DNA-RNA heteroduplexes could be specifically degraded by DSN and the SERS nanotags that were released from the surface of [email protected] MNPs. Meanwhile, the target p21 mRNA and miRNA-21 were released and then involved in the next round of signal reactions. The proposed strategy allowed quantitative detection of p21 mRNA and miRNA-21 and the limit of detection (LOD) was 0.12 fM and 0.17 fM, respectively. This method gives a great potential for multiplex detection of biological molecules.
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http://dx.doi.org/10.1016/j.talanta.2021.122432DOI Listing
September 2021

Effects of Different Nitrogen Sources and Ratios to Carbon on Larval Development and Bioconversion Efficiency in Food Waste Treatment by Black Soldier Fly Larvae ().

Insects 2021 May 31;12(6). Epub 2021 May 31.

Department of Environmental Ecological Engineering, School of Marine Science and Technology, Dalian University of Technology, Panjin 124221, China.

Biowaste treatment by black soldier fly larvae (BSFL, ) has received global research interest and growing industrial application. Larvae farming conditions, such as temperature, pH, and moisture, have been critically examined. However, the substrate carbon to nitrogen ratio (C/N), one of the key parameters that may affect larval survival and bioconversion efficiency, is significantly less studied. The current study aimed to compare the nitrogen supplying effects of 9 nitrogen species (i.e., NHCl, NaNO, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, /), soybean flour, and fish meal) during food waste larval treatment, and further examine the C/N effects on the larval development and bioconversion process, using the C/N adjustment with urea from the initial 21:1 to 18:1, 16:1, 14:1, 12:1, and 10:1, respectively. The food wastes were supplied with the same amount of nitrogen element (1 g N/100 g dry wt) in the nitrogen source trial and different amount of urea in the C/N adjustment trial following larvae treatment. The results showed that NHCl and NaNO caused significant harmful impacts on the larval survival and bioconversion process, while the 7 organic nitrogen species resulted in no significant negative effect. Further adjustment of C/N with urea showed that the C/N range between 18:1 and 14:1 was optimal for a high waste reduction performance (73.5-84.8%, < 0.001) and a high larvae yield (25.3-26.6%, = 0.015), while the C/N range of 18:1 to 16:1 was further optimal for an efficient larval protein yield (10.1-11.1%, = 0.003) and lipid yield (7.6-8.1%, = 0.002). The adjustment of C/N influenced the activity of antioxidant enzymes, such as superoxide dismutase (SOD, = 0.015), whereas exerted no obvious impact on the larval amino acid composition. Altogether, organic nitrogen is more suitable than NHCl and NaNO as the nitrogen amendment during larval food waste treatment, addition of small amounts of urea, targeting C/N of 18:1-14:1, would improve the waste reduction performance, and application of C/N at 18:1-16:1 would facilitate the larval protein and lipid bioconversion process.
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http://dx.doi.org/10.3390/insects12060507DOI Listing
May 2021

Enhancement of plasma-catalytic oxidation of ethylene oxide (EO) over FeMn catalysts in a dielectric barrier discharge reactor.

Sci Total Environ 2021 Sep 11;788:147675. Epub 2021 May 11.

State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science & Technology, Wuhan 430074, Hubei Province, China. Electronic address:

In this work, an integrated system combining non-thermal plasma (NTP) and FeMn catalysts was developed for ethylene oxide (EO) oxidation. The effect of Fe/Mn molar ratio on the oxidation rate of EO and energy yield of the plasma-catalytic process has been investigated as a function of specific energy density (SED). Compared with the case of using plasma alone, the combination of plasma and FeMn catalysts greatly enhanced the reaction performance by the factor of 25.2% to 97.6%. The maximum oxidation rate of 98.8% was achieved when FeMn catalyst was placed in the dielectric barrier discharge (DBD) reactor at the SED of 656.1 J·L. The highest energy yield of 2.82 g·kWh was obtained at the SED of 323.2 J·L over the FeMn catalyst. The interactions between Fe and Mn species resulted in larger specific surface area of the catalyst. Moreover, the reducibility of the catalysts was improved, while more surface adsorbed oxygen (O) was detected on the catalyst surfaces. Moreover, the redox cycles between Fe and Mn species facilitated consumption and supplementation of reactive oxygen species, which contributed to the plasma-catalytic oxidation reactions. The major reaction products of plasma-induced EO oxidation over the FeMn catalysts, including CHCOOH, CHCHO, CH, CH and CH, were observed using the FT-IR analyzer and GC-MS instrument. The reaction mechanisms of EO oxidation were discussed in terms of both gas-phase reaction and catalyst surface reaction. The redox cycles between Fe and Mn species facilitated the plasma reaction and accelerated the deep oxidation of by-products.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147675DOI Listing
September 2021

Evaluation of the risk of fracture in type 2 diabetes mellitus patients with incretins: an updated meta-analysis.

Endokrynol Pol 2021 May 19. Epub 2021 May 19.

Hospital of the southwest university of political science and law.

Context: Effect of incretins including DPP4-Is and GLP1-ras in the treatment of type 2 diabetes increases the risk of fracture remains controversial. And no meta-analysis has been written to discuss this from the prospective interventional studies. Objective:To evaluate the association between the using of incretins and fracture risk.

Methods: Multiple databases were search for original articles that investigated the relationship between the use of incretin agents and fractures risk up to December 2019. Trials were pooled using the Mantel-Haenszel method to calculate OR and 95% CI. The multiple sensitivity, heterogeneity, publication bias and quality were analyzed to evaluate the robustness of results among studies.

Results: The fixed-effects model was used on account of the I2 test for heterogeneity (I2 = 0.0%). Incretins were not associated with fracture risks. [0.97 (95% CI: 0.88~1.08)]. But in the subgroup analysis, when sitagliptin 100mg (OR 0.495, 95% CI: 0.304~0.806) or liraglutide 1.8mg was administered per day (OR 0.621, 95% CI: 0.413~0.933), it reduced fracture risk. The sensitivity analysis and publication bias prompted the robustness of results.

Conclusions: This meta-analysis suggested that current use of incretins not only is safe for fracture in type 2 diabetes patients from RCT studies, but also when sitagliptin 100mg or liraglutide 1.8mg per day was administered, they may have exhibited protective effects on bone metabolism.
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http://dx.doi.org/10.5603/EP.a2021.0031DOI Listing
May 2021

Quantitative SERS sensor based on self-assembled [email protected] heterogeneous nanocuboids monolayer with high enhancement factor for practical quantitative detection.

Anal Bioanal Chem 2021 May 14. Epub 2021 May 14.

The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, Anhui, China.

Accurate and rapid quantitative detection of pesticide and pollutant levels in the actual sample can aid in protecting food security, environmental security, and human health. A high Raman enhancement factor and good repeatability of the surface-enhanced Raman spectroscopy (SERS) substrates are favorable to quantitative analysis. Herein, a quantitative SERS sensor based on constructed self-assembled plasmonic [email protected] heterogeneous nanocuboids ([email protected] NCs) monolayer was developed. The sensor was used to quantitatively detect the trace pesticides extracted from pear surfaces and pollutants in fishpond water. Densely packed [email protected] NCs fabricated into large-scale monolayer films were chemically functionalized using 4-methyl-thiobenzoic acid (4-MBA) at the organic/aqueous interface, in which plentiful nanogaps contribute to increase hotspots. Their sharp corners and edges make the sensor have high SERS performance through providing abundant "hot spots." The obtained optically SERS-based sensor with uniform liquid-state interfacial nanoparticle arrays appeared to have nice SERS performance and uniformity using crystal violet (CV) as a probe molecule. In particular, the proposed SERS sensor was applied for quantitative detection of thiabendazole (TBZ) extracted from pear surfaces and malachite green (MG) in fishpond water down to levels of 0.0105 nM and 0.87 nM for SERS assay respectively. As a result, our proposed SERS quantitative detection strategy is quite preferred to on-site analysis and supervision of contaminant in food samples.
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http://dx.doi.org/10.1007/s00216-021-03366-9DOI Listing
May 2021

Environmental exposure to perfluoroalkyl substances in early pregnancy, maternal glucose homeostasis and the risk of gestational diabetes: A prospective cohort study.

Environ Int 2021 May 11;156:106621. Epub 2021 May 11.

Ministry of Education -Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Jiao Tong University School of Public Health, Shanghai, China. Electronic address:

Background: Humans are widely exposed to environmental perfluoroalkyl substances (PFAS), which may affect glucose homeostasis. However, research linking PFAS exposure to glucose homeostasis during pregnancy is limited and the results were inconsistent. We aimed to investigate the association between PFAS exposure and glucose homeostasis in pregnancy in a large prospective cohort.

Methods: A total of 2747 pregnant women who participated in the Shanghai Birth Cohort, had blood samples in early pregnancy and completed a 75 g oral glucose tolerance test (OGTT) at 24-28 gestational weeks were included. 10 PFAS were determined by high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS-MS) in the plasma samples in early pregnancy. Logistic regression was used to explore the associations between PFAS concentrations and gestational diabetes mellitus (GDM), while multiple linear regression was used to model the associations between PFAS and OGTT fasting, 1-h and 2-h glucose levels. Potential confounders were adjusted. Bayesian kernel machine regression (BKMR) and a quantile-based g-computation approach (qgcomp) were employed to explore the joint and independent effects of PFAS on glucose homeostasis.

Results: The incidence of GDM was 11.8%. One log-unit increment in plasma concentrations in early pregnancy was associated with an increased risk of GDM for perfluorobutane sulfonate (PFBS) (adjusted odd ratio (aOR) = 1.23, 95% confidence interval (95% CI): 1.05, 1.44) and perfluoroheptanoic acid (PFHpA) (aOR = 1.25, 95% CI: 1.07, 1.46). Perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorohexanesulfonate (PFHxS) and PFHpA were positively correlated with 1-h and 2-h glucose levels. Results of the mixed exposure model showed that the joint effects of PFAS were significantly associated with abnormal glucose homeostasis; In the BKMR model, PFAS mixture exposure was positively associated with the GDM incidence, 1-h and 2-h glucose levels and negatively correlated with FBG level. A similar trend could be observed in qgcomp and the positive correlation between PFAS and 2-h glucose level was significant (β = 0.12, 95% CI: 0.04, 0.20). PFOS, PFNA and PFHpA may be the main contributors after controlling for other PFAS congeners. PFOS was significantly correlated with GDM incidence and 2-h glucose level, and PFHpA was significantly associated with FBG and 2-h glucose levels. The above associations were more prominent among women with a normal prepregnant BMI.

Conclusions: Environmental exposure to PFAS may affect glucose homeostasis in pregnancy and increase the risk of GDM, especially in normal weight women.
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http://dx.doi.org/10.1016/j.envint.2021.106621DOI Listing
May 2021

Combining Serum DNA Methylation Biomarkers and Protein Tumor Markers Improved Clinical Sensitivity for Early Detection of Colorectal Cancer.

Int J Genomics 2021 21;2021:6613987. Epub 2021 Apr 21.

Department of Clinical Laboratory, Nanjing Integrated Traditional Chinese and Western Medicine Hospital, Nanjing, Jiangsu 210014, China.

Background: Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide and in China. Early CRC screening is the best approach to reduce its incidence and mortality rates. The ColoDefense test, a multiplex qPCR assay simultaneously detecting both methylated and genes, has demonstrated improved clinical performance on either methylation biomarker alone for CRC screening with both blood and stool samples.

Method: Leftover blood chemistry test samples from 125 CRC, 35 advanced adenoma, and 35 small polyp patients and 92 healthy control subjects were examined by the ColoDefense test. Among these samples, the levels of three circulating tumor markers, CEA, AFP, and CA19-9, were also measured for 106 CRC, 28 advanced adenoma, and 20 small polyp patients and all control subjects.

Results: Due to the smaller volume and extended storage in nonfrozen state, the ColoDefense test with these samples exhibited reduced performance for all stages of CRC and advanced adenomas. The performance of CEA, AFP, and CA19-9 and their various combinations was also evaluated for CRC screening to identify the tumor marker combinations with the best performance. When combined with the ColoDefense test, the identified combinations did improve the clinical performance.

Conclusion: These results suggested a rational path towards developing a CRC screening method that takes advantage of leftover blood chemistry test samples. The successful development of such a method will undoubtedly help promote early CRC screening by increasing its accessibility for the general public.
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http://dx.doi.org/10.1155/2021/6613987DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8084680PMC
April 2021

The copper-catalyzed selective monoalkylation of active methylene compounds with alkylsilyl peroxides.

Org Biomol Chem 2021 03 9;19(12):2658-2662. Epub 2021 Mar 9.

School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China.

A novel method for a mild copper-catalyzed selective monoalkylation of active methylene compounds with various alkylsilyl peroxides has been developed. The reaction has a broad substrate scope and our mechanistic studies suggest the participation of radical species in this alkylation reaction.
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http://dx.doi.org/10.1039/d1ob00075fDOI Listing
March 2021

Electrophysiological characterization of photoreceptor-like cells in human inducible pluripotent stem cell-derived retinal organoids during in vitro maturation.

Stem Cells 2021 Mar 4. Epub 2021 Mar 4.

Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, People's Republic of China.

Retinal organoids (ROs) derived from human inducible pluripotent stem cells (hiPSCs) exhibit considerable therapeutic potential. However, current quality control of ROs during in vitro differentiation is largely limited to the detection of molecular markers, often by immunostaining, polymerase chain reaction (PCR) assays and sequencing, often without proper functional assessments. As such, in the current study, we systemically characterized the physiological maturation of photoreceptor-like cells in hiPSC-derived ROs. By performing patch-clamp recordings from photoreceptor-like cells in ROs at distinct differentiation stages (ie, Differentiation Day [D]90, D150, and D200), we determined the electrophysiological properties of the plasma membrane and several characteristic ion channels closely associated with the physiological functions of the photoreceptors. Ionic hallmarks, such as hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and cyclic nucleotide-gated (CNG) channels, matured progressively during differentiation. After D200 in culture, these characteristic currents closely resembled those in macaque or human native photoreceptors. Furthermore, we demonstrated that the hyperpolarization-activated inward current/depolarization-activated outward current ratio (I /I ), termed as the inward-outward current (IOC) ratio hereon, accurately represented the maturity of photoreceptors and could serve as a sensitive indicator of pathological state. Thus, this study provides a comprehensive dataset describing the electrophysiological maturation of photoreceptor-like cells in hiPSC-derived ROs for precise and sensitive quality control during RO differentiation.
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http://dx.doi.org/10.1002/stem.3363DOI Listing
March 2021

The Formation of C-C or C-N Bonds via the Copper-Catalyzed Coupling of Alkylsilyl Peroxides and Organosilicon Compounds: A Route to Perfluoroalkylation.

Org Lett 2021 Mar 24;23(5):1809-1813. Epub 2021 Feb 24.

School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China.

The copper-catalyzed selective cleavage of alkylsilyl peroxides and the subsequent formation of carbon-carbon or carbon-nitrogen bonds with organosilicon compounds are described. The reaction proceeds under mild conditions and exhibits a broad substrate scope with respect to both cyclic and acyclic alkylsilyl peroxides in combination with carbon and nitrogen sources. In particular, this approach enables the facile radical perfluoroalkylation using commercially available perfluoroalkyltrimethylsilanes. Our mechanistic studies suggest that the reaction should proceed via a free-radical process.
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http://dx.doi.org/10.1021/acs.orglett.1c00215DOI Listing
March 2021

PEGylated DOX-coated nano graphene oxide as pH-responsive multifunctional nanocarrier for targeted drug delivery.

J Drug Target 2021 Feb 18:1-8. Epub 2021 Feb 18.

School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China.

Nano graphene oxide (NGO) has high drug-loading capacity due to its huge surface area. However, the limited stability and the poor biocompatibility of NGO hampered its application as drug delivery carrier under physiological conditions. Thereby, a new strategy of using chemical conjugation on NGO with hydrophilic polymers was adopted but currently was too complicated, low yield and costly. In this study, doxorubicin-hyd-PEG-folic acid (DOX-hyd-PEG-FA) polymers were coated on the surface of NGO π-π stocking and the hydrophobic effect between DOX and NGO. With the PEG shell protection, the biocompatibility of NGO was significantly improved. The drug-loading capacity of nanoparticles was more than 100%. FA ligands on the nanoparticle could guide the nanoparticles actively targeting to tumour cells. The hydrazone bond between DOX and PEG was decomposed spontaneously in the weakly acidic environment, which made PEG layer dissociated from NGO. Furthermore, DOX was easily protonized at low pH conditions, which weakened the interaction between DOX and NGO. Thus, DOX could be released rapidly from the nanoparticles in tumour cells. In summary, [email protected] is an easy-prepared nanoparticle with excellent biocompatibility, high pH-sensitivity and active tumour targeting. Therefore, it is a promising multifunctional nanocarrier effective for targeted drug delivery.
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http://dx.doi.org/10.1080/1061186X.2021.1887200DOI Listing
February 2021

Characterization of the complete chloroplast genome of L. var. Naud.

Mitochondrial DNA B Resour 2020 Jul 11;5(3):2744-2745. Epub 2020 Jul 11.

Lianyungang Academy of Agricultural Sciences, Lianyungang, P. R. China.

L. var. Naud chloroplast genome sequence was first reported. The size of the chloroplast genome is 156,016 bp in length, including a large single copy region (LSC) of 86,334 bp, a small single copy region (SSC) of 18,088 bp, and a pair of inverted repeat (IRa and IRb) regions with 25,797 bp. L. var. Naud chloroplast genome encodes 133 genes, including 88 genes, 37 genes, and eight genes. Phylogenetic analysis with the reported chloroplast sequences shows that L. var. Naud was closely related to
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http://dx.doi.org/10.1080/23802359.2020.1788431DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7782708PMC
July 2020

Size-dependent surface enhanced Raman scattering activity of plasmonic [email protected] for rapid and sensitive detection of Butyl benzyl phthalate.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Mar 23;248:119131. Epub 2020 Nov 23.

The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China. Electronic address:

Phthalate plasticizers (PAEs) are heavily applied to plastic products and poses severe threat to human health. Herein, it is especially urgent to find a stable and reliable method for detecting PAEs. In this report, a Surface Enhanced Raman Scatting (SERS) strategy coupled with plasmonic core-shell Au [email protected] nanocubes ([email protected]) as substrates were employed for the rapid and sensitive detection of Butyl benzyl phthalate (BBP) in liquor samples, and plasmonic core-shell [email protected] tend to perform richer localized surface plasmon resonance (LSPR) than AuNS. In this work, different sizes [email protected] comprised of Au nanospheres as core and Ag nanocubes as shells were synthesized. Based on this, we then investigated the SERS activity of BBP and crystal violet (CV) reached a maximum level when the thickness of Ag coating shell arrived in a threshold, and even very low signal of trace BBP dissolved in liquor sample can be detected in existence of the plasmonic [email protected] active substrate of 50 nm. The sensitivity and repeatability of the optimized size [email protected] have been estimated and limits of detection (LOD) was 10 M for BBP. In addition, finite difference time domain (FDTD) electromagnetic simulations also performed in great agreement with our experimental results.
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http://dx.doi.org/10.1016/j.saa.2020.119131DOI Listing
March 2021

[Selenoprotein thioredoxin reductase mediated menadione reduction: catalytic properties & inhibition effects].

Sheng Wu Gong Cheng Xue Bao 2020 Oct;36(10):2139-2150

School of Life and Pharmaceutical Sciences (LPS) and Panjin Institute of Industrial Technology, Dalian University of Technology, Panjin 124221, Liaoning, China.

Thioredoxin reductase (TrxR) is one class of the most important antioxidant selenoproteins and is involved in regulating tumor genesis and progression. It has been reported that naphthoquinones can target and inhibit TrxR1 activity therefore produce reactive oxygen species (ROS) mediated by TrxR1, resulting into cellular redox imbalance and making the naphthoquinone compounds to become potential antitumor chemotherapy drugs. The purpose of this work is to explore the interaction between TrxR1 and menadione using biochemical and mass-spectrometric (MS) analyses, to further reveal the detailed mechanisms of TrxR1-mediated naphthoquinone reduction and inhibition of TrxR1 by naphthoquinone compounds. Using the site-directed mutagenesis and recombinantly expressed TrxR1 variants, we measured the steady-state kinetic parameters of menadione reduction mediated by TrxR1 and its variants, performed the inhibition analysis of menadione on TrxR1 activity, and eventually identified the interaction between menadione and TrxR1 through MS analysis. We found that Sec-to-Cys mutation at residue of 498 significantly enhanced the efficiency of TrxR1-mediated menadione reduction, though the Sec⁴⁹⁸ is capable to catalyze the menadione reduction, indicating that TrxR1-mediated menadione reduction is dominantly in a Se-independent manner. Mutation experiments showed that Cys⁴⁹⁸ is mainly responsible for menadione catalysis in comparison to Cys⁴⁹⁷, while the N-terminal Cys⁶⁴ is slightly stronger than Cys⁵⁹ regarding the menadione reduction. LC-MS results detected that TrxR1 was arylated with one molecule of menadione, suggesting that menadione irreversibly modified the hyper-reactive Sec residue at the C-terminus of selenoprotein TrxR1. This study revealed that TrxR1 catalyzes the reduction of menadione in a Se-independent manner meanwhile its activity is irreversibly inhibited by menadione. Hereby it will be useful for the research and development of naphthoquinone anticancer drugs targeting TrxR1.
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http://dx.doi.org/10.13345/j.cjb.200066DOI Listing
October 2020

Strain and Electric Field Controllable Schottky Barriers and Contact Types in Graphene-MoTe van der Waals Heterostructure.

Nanoscale Res Lett 2020 Sep 21;15(1):180. Epub 2020 Sep 21.

Department of Applied Physics, School of Physics and Electronics, Hunan University, Changsha, 410082, China.

Two-dimensional (2D) transition metal dichalcogenides with intrinsically passivated surfaces are promising candidates for ultrathin optoelectronic devices that their performance is strongly affected by the contact with the metallic electrodes. Herein, first-principle calculations are used to construct and investigate the electronic and interfacial properties of 2D MoTe in contact with a graphene electrode by taking full advantage of them. The obtained results reveal that the electronic properties of graphene and MoTe layers are well preserved in heterostructures due to the weak van der Waals interlayer interaction, and the Fermi level moves toward the conduction band minimum of MoTe layer thus forming an n type Schottky contact at the interface. More interestingly, the Schottky barrier height and contact types in the graphene-MoTe heterostructure can be effectively tuned by biaxial strain and external electric field, which can transform the heterostructure from an n type Schottky contact to a p type one or to Ohmic contact. This work provides a deeper insight look for tuning the contact types and effective strategies to design high performance MoTe-based Schottky electronic nanodevices.
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http://dx.doi.org/10.1186/s11671-020-03409-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7505914PMC
September 2020

Determination of estrogens by solid-phase quadruplex stable isotope dansylation coupled with liquid chromatography-high resolution mass spectrometry in environmental samples.

Talanta 2020 Nov 15;219:121272. Epub 2020 Jun 15.

School of Ocean Science and Technology, Dalian University of Technology, Panjin, 124221, China. Electronic address:

Estrogens distribute widely in the environment as endocrine-disrupting chemicals (EDCs), which have to be monitored to evaluate their environmental impact. Aim to improve the analytical throughput of liquid chromatography-high resolution mass spectrometry (LC-HRMS), a quadruplex stable isotope dansylation method was developed, with which three real samples could be quantitatively analyzed in one injection. As the estrogens were at trace level in complex matrices, magnetic solid-phase extraction (MSPE) was applied to enrich these analytes and remove the interfaces. By integrating MSPE and quadruplex stable isotope dansylation, a solid-phase quadruplex labeling method was developed for the LC-HRMS analysis of estrogen analogues. For the tested seven estrogens, the developed method showed low detection limits (0.1-0.5 ng/L for pond water and 0.01-0.05 μg/kg for poultry manure), good precision (RSD < 5.5%) and accuracy (96.8-108.3%). The method was applied in the determination of estrogens in environmental samples, and the results revealed that all the tested estrogens were present in the estuary water (unquantifiable to 71.2 ng/L) and chicken manure (undetectable to 25.43 μg/kg).
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http://dx.doi.org/10.1016/j.talanta.2020.121272DOI Listing
November 2020

A novel SERS selective detection sensor for trace trinitrotoluene based on meisenheimer complex of monoethanolamine molecule.

Talanta 2020 Oct 14;218:121157. Epub 2020 May 14.

The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, China.

Trinitrotoluene (TNT) is a primary component in chemical explosives, making them a common focus in public safety detection. However, it is very difficult to achieve selective and sensitive detection of the TNT molecule in practical application. In the present study, a simple surface enhanced Raman scattering (SERS) sensing based on monoethanolamine (MEA) - modified gold nanoparticles (Au NPs) was expanded for high selectivity and sensitive detecting of TNT in an envelope, luggage, lake water, and clothing through a quickly sampling and detection process. The monoethanolamine molecule based on Meisenheimer complex lights up ultra-high Raman scattering of a nonresonant molecule on the superficial coat of gold nanoparticles. Using this detection sensor, a molecular bridge can be established to selectively detect trinitrotoluene with a detection limit of 21.47 pM. We were able to rapidly identification trinitrotoluene molecule with a powerful selective over the familiar interfering substances nitrophenol, picric acid, 2,4-dinitrophenol, and 2,4-dinitrotoluene. The outcome in this work supply an efficient solution to the test of trinitrotoluene and to establishing a SERS sensor analytical strategy. The studies have demonstrated that the MEA-Au NPs based SERS sensing can be potentially used in field detection the trace amount of chemical explosives for public security.
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http://dx.doi.org/10.1016/j.talanta.2020.121157DOI Listing
October 2020

Hypervalent Iodine-Mediated Diastereoselective α-Acetoxylation of Cyclic Ketones.

Front Chem 2020 10;8:467. Epub 2020 Jul 10.

School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, China.

A binary hybrid system comprising a hypervalent iodine(III) reagent and BF•OEt Lewis acid was found to be effective for the diastereoselective α-acetoxylation of cyclic ketones. In this hybrid system, BF•OEt Lewis acid allowed the activation of the hypervalent iodine(III) reagent and cyclic ketones for smooth α-acetoxylation reaction, achieving high diastereoselectivity. This hypervalent iodine-mediated α-acetoxylation of the cyclic ketone reaction plausibly undergoes an S2 substitution mechanism via an α--bound hypervalent iodine intermediate. The diastereoselectivity of the reaction mainly originates from thermodynamic control.
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http://dx.doi.org/10.3389/fchem.2020.00467DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7365914PMC
July 2020

Evaluation of the diagnostic value of joint PET myocardial perfusion and metabolic imaging for vascular stenosis in patients with obstructive coronary artery disease.

J Nucl Cardiol 2020 May 21. Epub 2020 May 21.

School of Biomedical Engineering and Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, 1023 Shatai Road, Guangzhou, 510515, Guangdong, China.

Background: To investigate the diagnostic value of joint PET myocardial perfusion and metabolic imaging for vascular stenosis in patients with suspected obstructive coronary artery disease (CAD).

Methods: Eighty-eight patients (53 and 35 applied for training and validation, respectively) with suspected obstructive CAD were referred to N-NH PET/CT myocardial perfusion imaging (MPI) and F-FDG PET/CT myocardial metabolic imaging (MMI) with available coronary angiography for analysis. One semi-quantitative indicator summed rest score (SRS) and five quantitative indicators, namely, perfusion defect extent (EXT), total perfusion deficit (TPD), myocardial blood flow (MBF), scar degree (SCR), and metabolism-perfusion mismatch (MIS), were extracted from the PET rest MPI and MMI scans. Different combinations of indicators and seven machine learning methods were used to construct diagnostic models. Diagnostic performance was evaluated using the sum of four metrics (noted as sumScore), namely, area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity.

Results: In univariate analysis, MIS outperformed other individual indicators in terms of sumScore (2.816-3.042 vs 2.138-2.908). In multivariate analysis, support vector machine (SVM) consisting of three indicators (MBF, SCR, and MIS) achieved the best performance (AUC 0.856, accuracy 0.810, sensitivity 0.838, specificity 0.757, and sumScore 3.261). This model consistently achieved significantly higher AUC compared with the SRS method for four specific subgroups (0.897, 0.839, 0.875, and 0.949 vs 0.775, 0.606, 0.713, and 0.744; P = 0.041, 0.005, 0.034 0.003, respectively).

Conclusions: The joint evaluation of PET rest MPI and MMI could improve the diagnostic performance for obstructive CAD. The multivariate model (MBF, SCR, and MIS) combined with SVM outperformed other methods.
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http://dx.doi.org/10.1007/s12350-020-02160-xDOI Listing
May 2020

Intrinsically altered lung-resident γδT cells control lung melanoma by producing interleukin-17A in the elderly.

Aging Cell 2020 02 5;19(2):e13099. Epub 2020 Jan 5.

Gerontology Institute of Anhui Province, The First Affiliated Hospital of University of Science and Technology of China (Anhui Provincial Hospital), Hefei, China.

Cancer is an age-associated disease, potentially related to the altered immune system of elderly individuals. However, cancer has gradually decreased incidence in the eldest globally such as the most common lung cancer, the mechanisms of which remain to be elucidated. In this study, it was found that the number of lung-resident γδT cells was significantly increased with altered gene expression in aged mice (20-24 months) versus young mice (10-16 weeks). Aged lung Vγ4 and Vγ6 γδT cells predominantly produced interleukin-17A (IL-17A), resulting in increased levels in the serum and lungs. Moreover, the aged mice exhibited smaller tumors and reduced numbers of tumor foci in the lungs after challenge with intravenous injection of B16/F10 melanoma cells compared with the young mice. Aged lung Vγ4 and Vγ6 γδT cells were highly cytotoxic to B16/F10 melanoma cells with higher expression levels of CD103. The markedly longer survival of the challenged aged mice was dependent on γδT17 cells, since neutralization of IL-17A or depletion of indicated γδT cells significantly shortened the survival time. Consistently, supplementation of IL-17A significantly enhanced the survival time of young mice with lung melanoma. Furthermore, the anti-tumor activity of aged lung γδT17 cells was not affected by alterations in the load and composition of commensal microbiota, as demonstrated through co-housing of the aged and young mice. Intrinsically altered lung γδT17 cells underlying age-dependent changes control lung melanoma, which will help to better understand the lung cancer progression in the elderly and the potential use of γδT17 cells in anti-tumor immunotherapy.
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http://dx.doi.org/10.1111/acel.13099DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6996947PMC
February 2020

Metals in Occluded Water: A New Perspective for Pollution in Drinking Water Distribution Systems.

Int J Environ Res Public Health 2019 08 9;16(16). Epub 2019 Aug 9.

Dalian University of Technology, No.2 Dagong Road, New District of Liaodong Bay, Panjin 124221, Liaoning, China.

Occluded water is water that remains inside corrosion scales within deteriorating distribution pipes. The accumulation of iron and manganese in the occluded water is a potential risk for water quality. Thus, this study investigated the change in metal (iron, manganese, copper and chromium) concentration in occluded water, the effect of these metals on the flowing water, and the source of iron and manganese in the occluded water using a simulation device. The results showed that total iron and total manganese were enriched in the occluded water, while the concentrations of total copper and total chromium in the occluded water gradually decreased over time. The iron and manganese in the occluded water migrate to the flowing water causing pollution in the flowing water. Also, copper and chromium adsorb on the corrosion scales within the pipes. The iron and manganese in the occluded water mainly came from the corrosion of the metal pipes, and the corrosion scales had a certain obstructive effect on the outward migration of iron in the occluded water but had less hindrance to the migration of manganese. Occluded water plays a critical role in the pollution of drinking water, and additional work is needed to control metal accumulation and release.
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http://dx.doi.org/10.3390/ijerph16162849DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6720301PMC
August 2019

SHP2 inhibitor specifically suppresses the stemness of KRAS-mutant non-small cell lung cancer cells.

Artif Cells Nanomed Biotechnol 2019 Dec;47(1):3231-3238

a Department of Pharmacy, Anhui No.2 Provincial People's Hospital , Hefei , China.

RAS mutations are frequent in non-small cell lung cancer (NSCLC). However, targeting RAS or the downstream/upstream effectors, such as tyrosine kinase inhibitors (TKIs), has been proved to be difficult. Here, we found that the stemness of KRAS-mutant NSCLC cells but not the KRAS-wild type NSCLC cells was promoted by TKIs treatment, as evident by the increase of ALDH1 activity, stemness marker expression and spheroid formation ability. Notably, SHP2 activation was found in KRAS-mutant NSCLC cells with TKIs treatment, as judged by the increase of tyrosine 542 phosphorylation (pSHP2 Y542), which activates the RAS/MEK/ERK pathway. On the contrary, inhibition of MEK was followed by a SHP2 activation in KRAS-mutant NSCLC cells. Additionally, inhibition of SHP2 attenuates the enhanced stemness of KRAS-mutant NSCLC cells induced by TKIs, characterized by decreasing ALDH1 activity, stemness marker expression and spheroid formation capacity, while had little effects on cell viability. Finally, we revealed that SHP2 inhibitor increased the sensitivity of TKIs and chemotherapy, which was potentiated by MEK inhibition. Our results suggest a possibility of using a combination of SHP2 inhibitor and TKIs for KRAS-mutant NSCLC treatment.
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http://dx.doi.org/10.1080/21691401.2019.1646748DOI Listing
December 2019

HS-β-cyclodextrin-functionalized [email protected]@Ag nanoparticles as a surface-enhanced Raman spectroscopy substrate for the sensitive detection of butyl benzyl phthalate.

Anal Bioanal Chem 2019 Sep 5;411(22):5691-5701. Epub 2019 Jul 5.

School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei, 230009, Anhui, China.

In recent years, there have been incidents involving the illegal addition of phthalic acid esters (PAEs) to liquors. It is well known that PAEs such as butyl benzyl phthalate (BBP) have estrogen-like effects, so high PAE levels in the body can lead to a decreased sperm count in males and altered sexual organ development in children, for example. The rapid detection of PAEs in liquor is therefore an important task. Compared with traditional methods of testing for PAEs, surface-enhanced Raman spectroscopy (SERS) offers higher sensitivity and the ability to search for chemical fingerprints, allowing the rapid detection of particular PAEs. In the present work, we synthesized [email protected]@Ag/β-cyclodextrin (CD) nanoparticles for use as a SERS-active substrate. FeO aggregates quickly under the influence of an external magnetic field, making it possible to magnetically separate out the NPs, which simplifies sample processing. The detection limit of the system for PAEs is also improved because the β-CD acts as a functional group with a cavity structure that is capable of adsorbing BBP to form a host (β-CD)-guest (BBP) complex. This substrate was shown to possess good repeatability and sensitivity when using malachite green (MG) as a probe molecule. Furthermore, the nanoparticle-based SERS substrate permitted the detection of BBP down to a level of 1.3 mg/kg in liquor, which is low enough to be able to detect BBP in real-world liquor samples. We expect that this method will prove useful for the rapid detection of PAEs in food. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-019-01947-3DOI Listing
September 2019

MicroRNA‑30a regulates cell proliferation, migration, invasion and apoptosis in human nasopharyngeal carcinoma via targeted regulation of ZEB2.

Mol Med Rep 2019 Aug 14;20(2):1672-1682. Epub 2019 Jun 14.

Department of Stomatology, People's Hospital of Longhua, Shenzhen, Guangdong 518109, P.R. China.

MicroRNA‑30a (miR‑30a) was previously reported to serve as a tumor suppressor able to inhibit the development and progression of certain types of cancer. A number of previous studies demonstrated that zinc finger E‑box binding homeobox 2 (ZEB2) may be regulated by miR‑30a in clear cell renal cell carcinoma and breast cancer. However, the function of miR‑30a in human nasopharyngeal carcinoma (NPC) remains unclear. The present study aimed to investigate the association between miR‑30a and ZEB2 in NPC. Therefore, the expression levels of miR‑30a and ZEB2 were measured in human NPC cells and tissues from patients with NPC, and the present results suggested that the expression level of miR‑30a was significantly decreased in NPC tissues compared with paracancerous tissues. The direct interaction between miR‑30a and the untranslated region of ZEB2 was examined using the dual‑luciferase reporter assay, and ZEB2 was identified as a direct target of miR‑30a. Additionally, the effects of miR‑30a and ZEB2 overexpression on cell proliferation, migration, invasion and apoptosis were additionally investigated. Functional experiments identified that overexpression of miR‑30a increased apoptosis and suppressed cell proliferation, cell migration and cell invasion by directly targeting ZEB2. Collectively, the present study suggested that miR‑30a may serve an important role in the progression of NPC and may represent a novel target for the treatment of patients with NPC.
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http://dx.doi.org/10.3892/mmr.2019.10387DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6625429PMC
August 2019

Bimetallic plasmonic [email protected] nanocuboids for rapid and sensitive detection of phthalate plasticizers with label-free surface-enhanced Raman spectroscopy.

Analyst 2019 Jun 17;144(12):3861-3869. Epub 2019 May 17.

Department of Pharmacy, Anhui University of Chinese Medicine, Anhui, Hefei 230038, China and The First Affiliated Hospital of USTC, Anhui Provincial Hospital, Anhui, Hefei 230001, China.

Phthalate plasticizers (PAEs) are posing a serious threat to human health, so it is urgent to develop effective and reliable ways to detect the food additives PAEs sensitively. In this study, we have reported plasmonic bimetallic [email protected] core-shell nanocuboids for the rapid and sensitive detection of PAEs in liquor samples with a label-free Surface-enhanced Raman Spectroscopy (SERS) strategy. Compared with single-element nanostructures, the bimetallic SERS platform can integrate two distinct functions into a single entity with unprecedented properties. Consequently, we synthesized [email protected] nanocuboids ([email protected] NCs) composed of a Au nanorod (Au NR) core and a Ag cuboid shell, which could produce richer and broader plasmonic resonance modes than Au NRs. It is obvious that the SERS signals of crystal violet (CV) and butyl benzyl phthalate (BBP) reached a maximum as the thickness of the Ag coating shell was in a certain threshold and there was a strong dependence of the Raman enhancement on the Ag cuboid shell-thickness. Based on the optimized size, the sensitivity and repeatability of [email protected] NCs were evaluated with limits of detection (LODs) at around 10 M both for BBP and diethylhexyl phthalate (DEHP). In addition, the SERS active substrate core-shell [email protected] NCs can be used to detect BBP as low as 1.3 mg kg spiked into the liquor samples. Thereby, the unique bimetallic [email protected] NCs showed a huge potential for the rapid and sensitive detection of PAEs in liquor samples.
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http://dx.doi.org/10.1039/c9an00251kDOI Listing
June 2019

Prevalence of and Risk Factors Associated with Polymerase Chain Reaction-Determined Positivity on Day 3 after Initiation of Artemether-Lumefantrine Treatment for Uncomplicated Malaria in Bagamoyo District, Tanzania.

Am J Trop Med Hyg 2019 05;100(5):1179-1186

Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala Universitet, Uppsala, Sweden.

Prevalence of and risk factors associated with polymerase chain reaction (PCR)-determined positivity were assessed on day 3 after initiation of treatment, pre-implementation and up to 8 years post-deployment of artemether-lumefantrine as first-line treatment for uncomplicated malaria in Bagamoyo district, Tanzania. Samples originated from previously reported trials conducted between 2006 and 2014. Cytochrome b-nested PCR was used to detect malaria parasites from blood samples collected on a filter paper on day 3. Chi-square and McNemar chi-squared tests, logistic regression models, and analysis of variance were used as appropriate. Primary outcome was based on the proportion of patients with day 3 PCR-determined positivity. Overall, 256/584 (43.8%) of screened patients had day 3 PCR-determined positivity, whereas only 2/584 (0.3%) had microscopy-determined asexual parasitemia. Day 3 PCR-determined positivity increased from 28.0% (14/50) in 2006 to 74.2% (132/178) in 2007-2008 and declined, thereafter, to 36.0% (50/139) in 2012-2013 and 27.6% (60/217) in 2014. When data were pooled, pretreatment microscopy-determined asexual parasitemia ≥ 100,000/µL, hemoglobin < 10 g/dL, age < 5 years, temperature ≥ 37.5°C, and year of study 2007-2008 and 2012-2013 were significantly associated with PCR-determined positivity on day 3. Significant increases in multidrug resistance gene 1 N86 and chloroquine resistant transporter K76 across years were not associated with PCR-determined positivity on day 3. No statistically significant association was observed between day 3 PCR-determined positivity and PCR-adjusted recrudescence. Day 3 PCR-determined positivity remained common in patients treated before and after implementation of artemether-lumefantrine in Bagamoyo district, Tanzania. However, its presence was associated with pretreatment characteristics. Trials registration numbers: NCT00336375, ISRCTN69189899, NCT01998295, and NCT02090036.
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http://dx.doi.org/10.4269/ajtmh.18-0729DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6493965PMC
May 2019

Magnetic liposomal emodin composite with enhanced killing efficiency against breast cancer.

Biomater Sci 2019 Feb;7(3):867-875

Department of Pharmacy, Department of Radiology, Anhui Provincial Hospital, Hefei, Anhui 230001, P. R. China.

As an active natural ingredient extracted from the plant Rheum palmatum, emodin exhibits various pharmacological activities, especially the inhibition of tumor growth and migration. However, the anticancer activity of emodin is limited mainly due to its poor solubility and the lack of specific targeting. Herein, we employed liposome to load emodin into the lipid bilayer, and high-performance ferromagnetic iron oxide nanocubes were simultaneously encapsulated in the hydrophilic bilayer. The optimized magnetic liposomal emodin nanocomposite (MLE) exhibited a 24.1% increase in the efficiency of killing MCF-7 cancer cells at a low concentration of 16 μg mL-1 compared with that of the hydrophobic free emodin. A further 8.67% enhancement of the killing efficiency was obtained by magnetic targeting. Benefitting from the high ferromagnetism, the transverse relaxivity (r2) of MLE was measured to be as high as 392.9 mM-1 s-1. With guidance from the external magnetic field, the effective accumulation of this magnetic liposome in the tumor region of a 4T1 breast tumor bearing mouse was observed by both MR tracking and fluorescence imaging, which should be beneficial for decreasing the required therapeutic dose of emodin. Hemolysis, cytotoxicity and biochemistry assays confirmed the excellent biocompatibility of this magnetic liposomal carrier. The anti-tumor therapeutic effect of MLE was further investigated in vivo, and the tumor in the therapeutic group was almost eliminated, indicating that this magnetic liposomal emodin could serve as a novel magnetically guided theranostic nanoagent.
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http://dx.doi.org/10.1039/c8bm01530aDOI Listing
February 2019

Complete Genome Sequence of Bacillus cereus CC-1, A Novel Marine Selenate/Selenite Reducing Bacterium Producing Metallic Selenides Nanomaterials.

Curr Microbiol 2019 Jan 20;76(1):78-85. Epub 2018 Oct 20.

Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, Panjin, 124221, Liaoning, China.

Metallic selenides nanomaterials are widely used in many fields, especially for photothermal therapy and thermoelectric devices. However, the traditional chemogenic methods are energy-intensive and environmentally unfriendly. In this study, the first complete genome data of a metallic selenides producing bacterium Bacillus cereus CC-1 was reported. This strain can not only reduce selenite and selenate into elemental selenium nanoparticles (SeNPs), but also synthesize several metallic selenides nanoparticles when adding metal ions (Pb, Ag and Bi) and selenite simultaneously. The size of the genome is 5,308,319 bp with 36.07% G+C content. Several putative genes responsible for heavy metal resistance, salt resistance, and selenate reduction were found. This genome data provide fundamental information, which support the use of this strain for the production of biocompatible photothermal and thermoelectric nanomaterials under mild conditions.
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http://dx.doi.org/10.1007/s00284-018-1587-9DOI Listing
January 2019

One-pot synthesis of dual carbon dots using only an N and S co-existed dopant for fluorescence detection of Ag.

Spectrochim Acta A Mol Biomol Spectrosc 2019 Feb 4;208:162-171. Epub 2018 Oct 4.

Department of Physics, Taiyuan University of Science and Technology, Taiyuan 030024, People's Republic of China. Electronic address:

Luminescent carbon-based nanoparticles, named often as carbon dots (CDs), were synthesized from citric acid (CA) and guanidine thiocyanate (GITC) via an N and S co-doped hydrothermal procedure. In the present structure characterization, N and S elements could be sufficiently doped by means of the heteroatom or the functional groups bonded on the surface of CDs. The as-prepared CDs solution showed blue color fluorescence under ultraviolet excitation, yet the PL spectra exhibited a repetitive emission process from excitation-independent to excitation-dependent. In view of the triexponential feature of fluorescence lifetimes of CDs, one possibility was proposed to be co-existence of two types of CDs with different surface states. Additionally, the as-prepared CDs were used as a sensing probe for the detection of Ag taking into consideration of the possible interactions between Ag and various fluorophores attached to the CD surface. As expected, the changes of fluorescence intensities were linearly proportional to the different concentration ranges of Ag, which suggests the complex nature of the quenching mechanism. And for the first time, the SCN group was found to accelerate the quenching of CDs towards Ag, promising a new approach for efficient detection of Ag for the application in industrial pollutants.
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http://dx.doi.org/10.1016/j.saa.2018.10.004DOI Listing
February 2019

Evaluation of compost, vegetable and food waste as amendments to improve the composting of NaOH/NaClO-contaminated poultry manure.

PLoS One 2018 11;13(10):e0205112. Epub 2018 Oct 11.

School of Food and Environment, Dalian University of Technology, Panjin campus, Panjin, China.

Regular usage of NaOH/NaClO disinfectants results in high sodium salt and alkalinity of poultry manure. This study compared three amendments: vegetable waste (V), food waste (F) and mature compost (C) for their ability to improve the composting of NaOH/NaClO-contaminated poultry manure. C compost resulted in the highest compost temperatures (p<0.001) and greatest reduction in OM, TC, TN and NH4-N (p<0.05). C and V composts were more efficient at lowering extractable-Na (ext-Na) and electrical conductivity (EC) than F (p<0.05). Maturity was primarily indicated by NH4-N, EC and ext-Na. Bacterial dynamics was profoundly influenced by NH4-N, EC and TC, with the decrease leading to discriminate genera shift from Sinibacillus and Thiopseudomonas to Brevbacterium, Brachybacterium, and Microbacterium. These findings suggest that mature compost was more desirable amendment than vegetable and food waste in the composting of NaOH/NaClO-contaminated poultry manure, and the decrease of ext-Na indicated compost maturity but did not influence bacterial dynamics.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0205112PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6181338PMC
April 2019