Publications by authors named "Xiaofei Ma"

90 Publications

Click preparation of multiple-thioether bridged cyclodextrin chiral materials for efficient enantioseparation in high-performance liquid chromatography.

Analyst 2021 May;146(9):3025-3033

School of Science, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin 300072, P. R. China.

A highly efficient covalent immobilization procedure is considered as an essential tool for obtaining stable and reliable cyclodextrin (CD) chiral stationary phases (CSPs). This work reports the "thiolene" click immobilization of heptakis(6-mercapto-6-deoxy)-β-CD-CSP onto alkene functional silica to afford novel multiple-thioether bridged CD CSPs by controlling the surface CD concentration. Solid-state NMR, FTIR, TGA and X-ray photoelectron diffraction spectroscopy (XPS) results proved the successful preparation of the desired CSPs with different surface CD loadings. The surface CD concentrations were calculated to be 0.49 and 0.68 μmol m-2 according to the elemental analysis results. More than 60 chiral enantiomers including isoxazolines, chiral lactides, chiral ketones, dansyl amino acids, small molecule acids and alkalis as well as some flavonoids were resolved or partially separated in the reversed-phase HPLC mode. Compared with the previously prepared single thiolene bridged CD-CSP, the current multiple-thioether CD-CSP afforded much better enantioseparation ability due to the existence of the thiol moiety and a confined structure.
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http://dx.doi.org/10.1039/d1an00145kDOI Listing
May 2021

Treatment and mechanism of fecal microbiota transplantation in mice with experimentally induced ulcerative colitis.

Exp Biol Med (Maywood) 2021 Apr 29:15353702211006044. Epub 2021 Apr 29.

Department of Anorectal, The Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, P.R. China.

Restoring intestinal microbiota dysbiosis with fecal microbiota transplantation is considered as a promising treatment for ulcerative colitis. However, the mechanisms underlying its relieving effects remain unclear. Ulcerative colitis pathogenesis is associated with the involvement of immune cells and inflammatory cytokines. Here, we aimed to investigate the effect of fecal microbiota transplantation on T cell cytokines in a dextran sulfate sodium-induced ulcerative colitis mouse model. Five-aminosalicylic acid (5-ASA) was used as the positive control. Male C57BL/6 mice were randomly assigned to control, model (UC), UC + FMT, and UC + 5-ASA groups. Each group consisted of five mice. The establishment of the mouse model was verified by fecal occult-blood screening and hematoxylin-eosin staining. Results showed that fecal microbiota transplantation reduced colonic inflammation, significantly decreased T helper (Th)1 and Th17 cells, interferon-gamma, interleukin-2 and interleukin-17, as well as significantly increased Th2 and regulatory T (Treg) cells, interleukin-4, interleukin-10, and transforming growth factor-beta, and improved routine blood count. Furthermore, 16S rRNA gene-sequencing analysis showed a significant increase in the relative abundance of genus and a significant decrease in the relative abundance of genus in the ulcerative colitis group. Fecal microbiota transplantation restored the profile of the intestinal microbiota to that of the control group. These findings demonstrated the capability of fecal microbiota transplantation in controlling experimentally induced ulcerative colitis by improving Th1/Th2 and Th17/Treg imbalance through the regulation of intestinal microbiota.
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http://dx.doi.org/10.1177/15353702211006044DOI Listing
April 2021

MicroRNA: Could It Play a Role in Bovine Endometritis?

Inflammation 2021 Apr 27. Epub 2021 Apr 27.

Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.

Endometritis in dairy cows is a major economic problem worldwide; without advances in lifestyle management and drug treatment, it causes high morbidity and death. Micro ribonucleic acid (miRNAs) these days is seen as an important part of gene control networks. It is a class of small nucleotides 20-25, single-stranded RNA molecules. In endometritis, the inflammatory response caused by the gram-negative bacteria Escherichia coli (E. coli) alters the expression of miRNA which can regulate the innate immune system. This manuscript reviews (1) the interaction of miRNAs with the signaling of NF-κB and dysregulation of miRNAs and NF-κB activity in endometritis and (2) the activity of miR-let-7c, miR-148a, and miR-488 in NF-κB activation and their effect on endometritis. Cows with reduced immunity are more vulnerable to transition diseases, such as endometritis. During post-partum, cows undergo stress, metabolic disorders, hormonal imbalance, negative energy balance, and changes in diet. One of the many categories of regulatory molecules, which explain its natural function and pathological impact on NF-κB dysregulation, is important to inform the complexity of the immune system and to develop treatments for endometritis. It shows that miRNAs could have multiple applications in veterinary medicine. Nevertheless, a comprehensive study of is essential which should be aimed at exploring the role of microRNA at physiological level and its effect due to dysfunction and dysregulation.
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http://dx.doi.org/10.1007/s10753-021-01458-3DOI Listing
April 2021

Interferon-τ regulates the expression and function of bovine leukocyte antigen by downregulating bta-miR-204.

Exp Ther Med 2021 Jun 8;21(6):594. Epub 2021 Apr 8.

Department of Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, P.R. China.

IFN-τ is a pregnancy recognition factor that regulates embryo implantation in ruminants. IFN-τ has been suggested to be involved in the expression of microRNA (miRNA/miR) and bovine leukocyte antigen (BoLA), which is an analog of the human major histocompatibility complex class I. However, little is known about whether the miRNAs are involved in the expression of BoLA in ruminants. The present study firstly verified that bta-miR-204 was downregulated and that BoLA was upregulated in the uterine tissues of dairy cows during early pregnancy. Subsequently, luciferase reporter assays, reverse transcription-quantitative PCR and western blot analysis were used to validate BoLA as the target gene of bta-miR-204. Moreover, BoLA was markedly upregulated and bta-miR-204 was downregulated in bovine endometrial epithelial cells (bEECs) treated with IFN-τ. In addition, the results indicated that when the expression level of BoLA was increased by IFN-τ, the expression level of programmed death-ligand 1 (PD-L1) and programmed death-ligand 2 (PD-L2) was also increased. Furthermore, when BoLA was silenced in bEECs by small interfering RNA, the expression of PD-L1 and PD-L2 was not affected by IFN-τ. The expression level of PD-L1 and PD-L2 was also increased in the uterine tissues of pregnant dairy cattle. In conclusion, IFN-τ may function by suppressing the expression of bta-miR-204 to increase the expression of BoLA during the embryo implantation period in cattle. IFN-τ may induce PD-L1 and PD-L2 transcription by regulating BoLA, which may influence the T cell immune response, thereby regulating pregnant cattle immunization.
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http://dx.doi.org/10.3892/etm.2021.10026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056107PMC
June 2021

Projections of desertification trends in Central Asia under global warming scenarios.

Sci Total Environ 2021 Mar 27;781:146777. Epub 2021 Mar 27.

School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China. Electronic address:

Central Asia (CA) is a core area of global desertification, but the effect of the intensifying "global greening" policy on the desertification process under global warming scenarios in CA remains unclear. Based on multi-source remote sensing data and Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) 2b climate data, this study investigated desertification in CA using actual evapotranspiration (ETa), temperature and precipitation as driving factors. Coupling with the CA-Markov model, the inversion method of desertification was improved, and the evolution normal form of desertification in CA was proposed. Finally, spatio-temporal variations of desertification in CA were quantified. The results indicate that temperature, precipitation, and normalized difference vegetation index (NDVI) in CA increased during the historical period (1980-2015), with sudden changes in 1994. In contrast, although ETa exhibited fluctuating increases (7.41 mm/10 yr) during this period, no sudden changes were observed in 1994. In the future (2006-2099), the climate of CA will become warmer and wetter. With reference to 1980-2005, precipitation under global warming of 2.0 °C (GW2.0) will be higher than that under global warming of 1.5 °C (GW1.5) by 10.3 mm, and ETa will increase by 20.88 mm and 27.54 mm under GW1.5 and GW2.0, respectively. Although the area of desert lands has decreased (5.94 × 10 km/10 yr), the area of potential desert lands has increased (0.17 × 10 km/10 yr). With global warming, this situation will continue to intensify, mainly in Xinjiang of China, and Kazakhstan. The Aral Sea plays an important role in the desertification of CA. The potential increase in desert land under GW2.0 is equivalent to the current water area of the Aral Sea. The findings could provide policy support for combating desertification in CA and promoting the achievement of the Sustainable Development Goals.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146777DOI Listing
March 2021

IFN-τ Attenuates LPS-Induced Endometritis by Restraining HMGB1/NF-κB Activation in bEECs.

Inflammation 2021 Feb 18. Epub 2021 Feb 18.

Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.

Endometritis is a common inflammatory disease in uterine tissues that leads to animal infertility. Among the causes, Escherichia coli infection is one of the main reasons. Interferon-tau (IFN-τ) is the initial pregnancy signal for ruminant embryos and can induce immune tolerance in humans and other species. However, there are scarce reports on whether IFN-τ has a regulatory effect on endometrial inflammatory damage through HMGB1-NF-κB signalling. The purpose of this study was to investigate the regulatory mechanism of IFN-τ in HMGB1-NF-κB signalling in LPS-induced endometritis. ELISA and qPCR were used to detect the expression of LPS-induced pro-inflammatory cytokines in bovine endometrial epithelial cells (bEECs or BEND) under IFN-τ intervention, and the levels of HMGB1, p-IKK and p-p65 were detected by Western blotting. The nuclear translocation of NF-κB p65 was determined through immunofluorescence. In addition, bEECs were transfected with si-HMGB1 to elucidate the key role of HMGB1 and IFN-τ in the endometrial inflammatory cascade. The results indicated that IFN-τ inhibits the expression of related pro-inflammatory cytokines in an inflammatory injury model of bovine endometrial epithelial cells induced by LPS. Furthermore, experiments have proven that IFN-τ has protective effects on E. coli endotoxin-induced endometritis in mice in vivo. IFN-τ inhibited the HMGB1-NF-κB axis and significantly reduced the secretion of pro-inflammatory cytokines, the expression of HMGB1 protein and the levels of IKK and NF-κB p65 phosphorylation. In summary, our results showed that IFN-τ resists E. coli endotoxin-induced endometritis by attenuating HMGB1/NF-κB signalling.
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http://dx.doi.org/10.1007/s10753-021-01433-yDOI Listing
February 2021

L-Histidinium Chiral Ionic Liquid Functionalized β-Cyclodextrin as Chiral Selector in Capillary Electrophoresis.

J Chromatogr Sci 2021 Mar;59(4):388-395

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P. R. China.

Nowadays, ionic liquids (ILs) functionalized cyclodextrins (CDs) have drawn increasing attention in chiral separation. Herein, a novel β-CD derivative functionalized by L-histidinium IL, mono-6-deoxy-6-L-histidinium-β-cyclodextrin chloride (L-HMCDCl), was synthesized for the first time and utilized for enantioseparation of nefopam and chlorphenamine in capillary electrophoresis. The L-HMCDCl exhibited superior enantioselectivity compared with native β-CD. The effect of some key parameters such as chiral selector concentration, buffer pH and applied voltage on the enantioseparation was investigated in detail. In the interest of the chiral discrimination mechanism and the enhanced enantioselectivity of L-HMCDCl, molecular modeling with AutoDock was employed to study the interaction, which was in good agreement with experimental results.
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http://dx.doi.org/10.1093/chromsci/bmaa115DOI Listing
March 2021

Chiral porous organic frameworks and their application in enantioseparation.

Anal Methods 2021 01 27;13(1):8-33. Epub 2020 Nov 27.

School of Science, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin 300350, P. R. China.

Porous organic frameworks (POFs) are a kind of porous material with a network structure composed of repeated monomers, which have excellent physical and chemical properties, such as a high surface area, high porosity, uniform pore sizes and structural diversity, and which have aroused broad interest among researchers. With the rapid development of materials science, increasingly more porous materials have been developed and applied, especially metal organic frameworks (MOFs) and covalent organic frameworks (COFs), which have been widely applied in the fields of luminous materials, catalytic research, adsorption and drug transport. One of the most important applications for chiral porous materials is in chiral separation and these materials have become a research hotspot in the field of chromatographic separation and analysis in recent years. In this review, from the viewpoint of enantioseparation, the synthesis of chiral porous materials and their applications in high-performance liquid chromatography (HPLC), capillary electrochromatography (CEC), and gas chromatography (GC) are reviewed. The typical applications of MOFs in solid-phase microextraction (SPME) are also discussed.
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http://dx.doi.org/10.1039/d0ay01831gDOI Listing
January 2021

Metal organic framework ZIF-90 modified with lactobionic acid for use in improved open tubular capillary electrochromatographic enantioseparation of five basic drugs.

Mikrochim Acta 2020 Nov 11;187(12):651. Epub 2020 Nov 11.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, People's Republic of China.

An in situ zeolite imidazole metal organic framework-90 (ZIF-90) modified capillary was prepared via the method of solvothermal synthesis. The coating of ZIF-90 was characterized by scanning electron microscopy, energy-dispersive X-ray spectrometry, and EOF. Capillary electrochromatography-based enantioseparation of the basic drugs propranolol (PRO), metoprolol (MET), atenolol (ATE), bisoprolol (BIS), and sotalol (SOT) was performed using lactobionic acid (LA) as the chiral selector. Compared with an uncoated silica capillary, the resolutions are greatly improved (PRO 1.40 → 3.23; MET 1.07 → 3.19; ATE 1.07 → 3.15; BIS 1.16 → 3.41; SOT 1.00 → 2.79). Effects of buffer pH values, proportion of organic additives, concentration of lactobionic acid, and applied voltage were investigated. Graphical abstract Schematic presentation of the preparation of zeolitic imidazolate framework-90 (ZIF-90) modified capillary (ZIF-90@capillary) for enantioseparation of drug enantiomers. The capillary was applied to construct capillary electrochromatography system with lactobionic acid for enantioseparation of basic chiral drugs.
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http://dx.doi.org/10.1007/s00604-020-04611-1DOI Listing
November 2020

Functional characterization of soybean (Glycine max) DIRIGENT genes reveals an important role of GmDIR27 in the regulation of pod dehiscence.

Genomics 2021 Jan 2;113(1 Pt 2):979-990. Epub 2020 Nov 2.

College of Life Sciences, Key Lab of Plant Biotechnology in Universities of Shandong Province, Qingdao Agricultural University, Qingdao 266109, China. Electronic address:

DIRIGENT (DIR) genes play important roles in regulating plant growth and development and have been studied in many plant species. However, information on DIR genes in soybean is limited. Here, we identified and characterized 54 GmDIRs and studied the characteristics of GmDIRs. Most of the GmDIRs contained a classical gene structure, one exon; 26 conserved motifs were found among these GmDIRs. The GmDIRs were grouped into four subfamilies, DIR-a, DIR-b, DIR-e and DIR-f, based on a phylogenetic analysis, and 24 duplicated gene pairs were identified. Differences in the cis-acting elements in the GmDIR promoter regions might result in distinct expression patterns of GmDIRs in different tissues. In addition, GmDIR27 had a close relationship with the pod dehiscence gene GmPdh1, and overexpression of GmDIR27 increased pod dehiscence by affecting several pod dehiscence-related gene expressions. Generally, our results provide essential information that aids future efforts to functionally characterize soybean GmDIR genes.
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http://dx.doi.org/10.1016/j.ygeno.2020.10.033DOI Listing
January 2021

Construction of a high-density SNP-based genetic map and identification of fruit-related QTLs and candidate genes in peach [Prunus persica (L.) Batsch].

BMC Plant Biol 2020 Sep 23;20(1):438. Epub 2020 Sep 23.

College of horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.

Background: High-density genetic mapping is a valuable tool for mapping loci that control specific traits for perennial fruit trees. Peach is an economically important fruit tree and a model Rosaceae species for genomic and genetic research. In peach, even though many molecular markers, genetic maps and QTL mappings have been reported, further research on the improvement of marker numbers, map densities, QTL accuracy and candidate gene identification is still warranted.

Results: A high-density single nucleotide polymorphism (SNP)-based peach linkage map was constructed using specific locus amplified fragment sequencing (SLAF-seq). This genetic map consisted of 7998 SLAF markers, spanning 1098.79 cM with an average distance of 0.17 cM between adjacent markers. A total of 40 QTLs and 885 annotated candidate genes were detected for 10 fruit-related traits, including fruit weight (FW), fruit diameter (FD), percentage of red skin colour (PSC), eating quality (EQ), fruit flavour (FV), red in flesh (RF), red around pit (RP), adherence to pit (AP), fruit development period (FDP) and fruit fibre content (FFC). Eighteen QTLs for soluble solid content (SSC) were identified along LGs 1, 4, 5, and 6 in 2015 and 2016, and 540 genes were annotated in QTL intervals. Thirty-two QTLs for fruit acidity content (FA) were detected on LG1, and 2, 4, 5, 6, and 1232 candidate genes were identified. The expression profiles of 2 candidate genes for SSC and 4 for FA were analysed in parents and their offspring.

Conclusions: We constructed a high-density genetic map in peach based on SLAF-seq, which may contribute to the identification of important agronomic trait loci. Ninety QTLs for 12 fruit-related traits were identified, most of which overlapped with previous reports, and some new QTLs were obtained. A large number of candidate genes for fruit-related traits were screened and identified. These results may improve our understanding of the genetic control of fruit quality traits and provide useful information in marker-assisted selection for fruit quality in peach breeding programmes.
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http://dx.doi.org/10.1186/s12870-020-02557-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7510285PMC
September 2020

MiR-505 as an anti-inflammatory regulator suppresses HMGB1/NF-κB pathway in lipopolysaccharide-mediated endometritis by targeting HMGB1.

Int Immunopharmacol 2020 Nov 20;88:106912. Epub 2020 Aug 20.

Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address:

Endometritis is characterized by severe inflammation and tissue damage. It is a common clinical disease that causes infertility due to infectious diseases of the reproductive system. MicroRNAs (miRNAs) are the current focus of research on the regulation of the inflammatory process and play a vital role in various inflammatory diseases. The highly conserved miR-505 regulates the mechanism of lipopolysaccharide (LPS) induced endometritis, but the extent to which pro-inflammatory genes are activated remains unclear. The results of this study showed that the expression of miR-505 was significantly down-regulated in mouse endometritis tissue and LPS-stimulated BEND cells. The study also showed that overexpression of miR-505 significantly suppressed the production of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, and this effect was reversed by inhibiting the expression of miR-505. Moreover, miR-505 inhibited the expression of HMGB1 by targeting its 3'-UTR, thereby inhibiting the activation of HMGB1/NF-κB signalling. Taken together, the results of this study further confirmed that miR-505, as an anti-inflammatory agent, regulates the activation of the HMGB1/NF-κB signalling pathway through negative feedback.
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http://dx.doi.org/10.1016/j.intimp.2020.106912DOI Listing
November 2020

Mechanism of TGF-β promoting chondrogenesis in human fat stem cells.

Biochem Biophys Res Commun 2020 10 8;530(4):725-731. Epub 2020 Aug 8.

Department of Plastic Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address:

Clinically deficient cartilage is difficult to regenerate, and the availability of chondrocytes is very limited. However, human adipose-derived stem cells (ADSCs) can be obtained easily and in sufficient quantities. Therefore, we will find a way of replacing chondrocytes with fat stem cells to solve the problem of seed cell origin. Previous studies have revealed that transforming growth factor-β (TGF-β) can promote chondrocyte differentiation and maturation. In this study, we found that TGF-β in the transforming growth factor family can effectively promote the transformation process from fat stem cells to chondrocytes, thus promoting chondrogenesis. At the same time, we also further reviewed and considered the mechanism of this process. Through flow cytometry, immunohistochemical, fluorescent microscopy, qRCR, Wb etc., we found that TGF-β mainly plays a role through wnt5a/β-catenin, promoting human fat stem cell growing into the cartilage. This discovery is expected to provide new ideas in the field of cartilage regeneration.
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http://dx.doi.org/10.1016/j.bbrc.2020.06.147DOI Listing
October 2020

Bacterial community colonization on tire microplastics in typical urban water environments and associated impacting factors.

Environ Pollut 2020 Oct 5;265(Pt B):114922. Epub 2020 Jun 5.

Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.

Only limited information is available on bacterial communities' dynamics on tire microplastics in urban water environments. This study exploited 16S rDNA high-throughput sequencing to characterize bacterial communities on tire microplastics, using three different tire brands and tire sizes, in two typical urban water environments, including an influent pond of constructed wetland (CW) and its subsequent effluent into a landscape river (LR) during three different periods, namely, 1 month, 3 and 6 months. Results showed that the abundance of bacterial colonization on tire microplastics will increase over time. Proteobacteria, Bacteroidetes were the dominant bacteria at a phylum level, although they exhibited dynamic changes. At a genus level, the identifiable bacteria found in tire microplastics was generally the common bacteria in wastewater discharge, such as Aquabacterium and Denitratisoma. Additionally, alpha diversity showed no significant differences in bacterial communities at the same locations. While beta diversity showed that the bacterial communities on the tire microplastics in the two locations was different. BugBase revealed that tire microplastics could support pathogenic bacteria in urban water environments. PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) indicated that the abundance of microorganisms associated with metabolism and degradation increased with time. Moreover, the ambient environmental factors were the main influencing factors of bacterial communities on tire microplastics. Herein, the contribution rate of nutrient salts (NO-N, NO-N, NH-N, CODcr) was approximately 63%, and that of environmental physical factors of T and pH was 50%. While physicochemical factors, including particle size, contact angle, element content only had a slight impact. Accordingly, tire microplastics, as an emerging environmental pollutant, can act as carries for bacterial colonization and propagation, particularly harmful microorganisms. Therefore, the obtained findings can provide new insight into potential risks of harmful microorganisms that colonize tire microplastics in urban water environments.
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http://dx.doi.org/10.1016/j.envpol.2020.114922DOI Listing
October 2020

Visual chiral recognition of aromatic amino acids with (S)-mandelic acid-based ionic liquids via complexation.

Talanta 2020 Sep 26;217:121083. Epub 2020 Apr 26.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, PR China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, PR China.

Recently, chiral ionic liquids have attracted increasing attention in analytical chemistry. However, only a few papers focus on the application of them in visual chiral recognition. Herein, two functionalized chiral ionic liquids derived from (S)-mandelic acid (1-butyl-3-methylimidazolium mandelate, CIL1 and N-butyl-N-methylpyrrolidinium mandelate, CIL2) were prepared for visual chiral recognition of aromatic amino acids for the first time. In the presence of Cu(II) and appropriate solvents, visual enantiomeric responses of phenylalanine, tryptophane, tyrosine and phenylglycine were observed. Relying on solubility or color differences, all chiral recognition could be finished within 5 min. The potential mechanism was investigated by means of infrared spectroscopy, ultraviolet spectroscopy, thermal gravity analysis, elemental analysis and scanning electron microscope. Results revealed that CuSO interacted with CIL1 and D-tryptophane in the ratio of 1:1.96:0.43 in relevant precipitate, and the different stability of complex was responsible for the chiral recognition. In addition, resolution of racemic tryptophane was performed, which offered excellent enantiomeric excess values (94.2% for CIL1 and 95.1% for CIL2 in solid phase). The proposed ionic liquids had strong enantioselectivity for aromatic amino acids and great potential in visual chiral recognition.
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http://dx.doi.org/10.1016/j.talanta.2020.121083DOI Listing
September 2020

Expression, location and biological effects of four and a half LIM domain protein 2 (FHL2) on granulosa cells in ovine.

Reprod Domest Anim 2020 Jun 8;55(6):737-746. Epub 2020 Apr 8.

College of Animal Science and Technology, Hebei Agricultural University, Baoding, China.

Previous studies have shown that four and a half LIM domain protein 2 (FHL2) plays an essential role in the regulation of follicular development in mammals. Although the FHL2 genes of human and mouse have been well characterized, the expression and location of FHL2 in ovary and the biological functions of FHL2 on granulosa cells (GCs) of ovine are still not clear. In this study, full-length complementary DNA (cDNA) of FHL2 from ovine follicular GCs was amplified by real-time PCR (RT-PCR). The expression and location of FHL2 in ovary and GCs of ovine were studied by immunohistochemistry and immunofluorescence, and the biological effects of FHL2 on the cell proliferation, cell apoptosis, cell cycles and expression level of related genes of ovine GCs were also explored by overexpression or knockdown of FHL2. The results indicated that FHL2 was expressed in ovine follicular GCs and the sequence of the FHL2 cDNA was consistent with that predicted in GenBank, which did not cause an amino acid change. According to the results, FHL2 was expressed in ovine ovary and mainly located in the cytoplasm and nucleus of GCs. In addition, overexpression of FHL2 significantly reduced the cell viability, promoted the cell apoptosis and decreased the percentage of G0/G1 and S phase cells. RT-PCR showed that overexpression of FHL2 significantly increased the mRNA expression level of Bax and decreased the expression of Bcl-2 and the Bcl-2/Bax mRNA ratio compared with the control group. Besides, the knockdown of FHL2 gene in ovine GCs significantly improved the cell viability, suppressed the cell apoptosis, decreased the mRNA expression level of Caspase-3 gene, increased the Bcl-2/Bax mRNA ratio and increased the percentage of S and G2/M phase cells. Our results suggest that FHL2 may play an important role in the biological functions of GCs in ovine.
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http://dx.doi.org/10.1111/rda.13675DOI Listing
June 2020

Ginsenoside Rb 1: A novel therapeutic agent in Staphylococcusaureus-induced Acute Lung Injury with special reference to Oxidative stress and Apoptosis.

Microb Pathog 2020 Jun 12;143:104109. Epub 2020 Mar 12.

Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China. Electronic address:

Acute lung injury (ALI) is considered as an uncontrolled inflammatory response that can leads to acute respiratory distress syndrome (ARDS), which limits the therapeutic strategies. Ginsenosides Rb1 (Rb1), an active ingredient obtained from Panax ginseng, possesses a broad range of pharmacological and medicinal properties, comprising the anti-inflammatory, anti-oxidant, and anti-tumor activities. Therefore, the purpose of the present study was to investigate the protective effects of Rb1 against S. aureus-induced (ALI) through regulation of Nuclear factor erythroid 2-related factor 2 (Nrf2) and mitochondrial-mediated apoptotic pathways in mice (in-vivo), and RAW264.7 cells (in-vitro). For that purpose, forty Kunming mice were randomly assigned into four treatment groups; (1) Control group (phosphate buffer saline (PBS); (2) S. aureus group; (3) S. aureus + Rb1 (20 mg/kg) group; and (4) Rb1 (20 mg/kg) group. The 20 μg/mL dose of Rb1 was used in RAW264.7 cells. In the present study, we found that Rb1 treatment reduced ALI-induced oxidative stress via suppressing the accumulation of malondialdehyde (MDA) and myeloperoxidase (MPO) and increase the antioxidant enzyme activities of superoxidase dismutase 1 (SOD1), Catalase (CAT), and glutathione peroxidase 1 (Gpx1). Similarly, Rb1 markedly increased messenger RNA (mRNA) expression of antioxidant genes (SOD1, CAT and Gpx1) in comparison with ALI group. The histopathological results showed that Rb1 treatment ameliorated ALI-induced hemorrhages, hyperemia, perivascular edema and neutrophilic infiltration in the lungs of mice. Furthermore, Rb1 enhanced the antioxidant defense system through activating the Nrf2 signaling pathway. Our findings showed that Rb1 treated group significantly up-regulated mRNA and protein expression of Nrf2 and its downstream associated genes down-regulated by ALI in vivo and in vitro. Moreover, ALI significantly increased the both mRNA and protein expression of mitochondrial-apoptosis-related genes (Bax, caspase-3, caspase-9, cytochrome c and p53), while decreased the Bcl-2. In addition, Rb1 therapy significantly reversed the mRNA and protein expression of these mitochondrial-apoptosis-related genes, as compared to the ALI group in vivo and in vitro. Taken together, Rb1 alleviates ALI-induced oxidative injury and apoptosis by modulating the Nrf2 and mitochondrial signaling pathways in the lungs of mice.
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http://dx.doi.org/10.1016/j.micpath.2020.104109DOI Listing
June 2020

Predicting the spatiotemporal variation in soil wind erosion across Central Asia in response to climate change in the 21st century.

Sci Total Environ 2020 Mar 23;709:136060. Epub 2019 Dec 23.

Research Center for Ecology and Environment of Central Asia, Chinese Academy of Sciences, Urumqi, China; Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resources and Environment, Linyi University, Linyi, China. Electronic address:

Wind erosion is an important environmental issue in Central Asia (CA), which includes Xinjiang, China (XJ-China), and the five CA states of the former Soviet Union (CAS5). Future climate changes could accelerate wind erosion in arid and semiarid areas and negatively impact local soil health and productivity. Based on the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP2b) climate model, we simulated the spatiotemporal dynamics of soil wind erosion from 1986 to 2099 in CA using the revised wind erosion equation (RWEQ) model. Our analysis indicated that the annual soil wind erosion modulus during the prediction period (2006-2099) increased compared with that in the reference period (1986-2005), especially in the 2030s (18.71%) and 2050s (18.85%) under RCP4.5. Spring and winter soil wind erosion will be the major contributors to increased annual wind erosion. We predicted that spring soil wind erosion will increase by 10.34% (RCP4.5) to 10.71% (RCP8.5) and that winter soil wind erosion will increase by 23.32% (RCP4.5) to 33.74% (RCP8.5) in the late 21st century. Annual soil wind erosion will increase in the northwest of CA, but decrease in the Karakum Desert, Kyzylkum Desert and Taklimakan Desert. Soil wind erosion varies under different plant functional types. By the late 21st century, the soil wind erosion modulus in grassland, irrigated cropland and rainfed cropland will increase by 62 t/km/a (RCP4.5) to 412 t/km/a (RCP8.5), 27 t/km/a (RCP4.5) to 88 t/km/a (RCP8.5) and 141 t/km/a (RCP4.5) to 237 t/km/a (RCP8.5), respectively. Our study indicates high risks of soil wind erosion in northwestern CA, and ecological engineering measures such as nature based solutions including ecological barriers should be developed to prevent soil loss in central and western Kazakhstan, where future warming will bring severe stress.
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http://dx.doi.org/10.1016/j.scitotenv.2019.136060DOI Listing
March 2020

Synthesis and application of tetramethylammonium-carboxymethylated-β-cyclodextrin: A novel ionic liquid in capillary electrophoresis enantioseparation.

J Pharm Biomed Anal 2020 Feb 5;180:113030. Epub 2019 Dec 5.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, PR China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, PR China.

In this study, a carboxymethylated-β-cyclodextrin-based chiral ionic liquid (CIL), tetramethylammonium-carboxymethylated-β-cyclodextrin (TMA-CM-β-CD) was successfully designed and synthesized. This cyclodextrin-based ionic liquids (ILs) was used as the sole chiral selector in capillary electrophoresis, and it is very interesting to find that the chiral separation capability can be remarkably improved when a conventional cyclodextrin chiral selector evolved into an IL chiral selector. The ionic liquid showed satisfactory separation performance towards twelve tested drugs. A series of parameters affecting the enantioseparation, such as the type and proportion of organic modifier, buffer pH, chiral selector concentration, as well as applied voltage were systematically investigated. Additionally, the molecular docking program Autodock was applied to further demonstrate the mechanism of chiral recognition and the enhanced enantioselectivity of TMA-CM-β-CD, which kept in agreement with our experimental results.
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http://dx.doi.org/10.1016/j.jpba.2019.113030DOI Listing
February 2020

A metal organic framework-functionalized monolithic column for enantioseparation of six basic chiral drugs by capillary electrochromatography.

Mikrochim Acta 2019 12 17;187(1):51. Epub 2019 Dec 17.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, People's Republic of China.

Poly(glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths were used as a support to grow a zeolitic imidazolate framework-8 (ZIF-8) via layer-by-layer self-assembly. Pepsin, acting as as chiral selector, was covalently linked to the surface of the amino-modified ZIF-8 through the Schiff base method. The material was characterized by scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy and elemental analysis. The pepsin-ZIF-8-poly(GMA-co-EDMA) column was utilized to the enantioseparation of the racemic forms of hydroxychloroquine (HCQ), chloroquine (CHQ), hydroxyzine (HXY), nefopam (NEF), clenbuterol (CLE) and amlodipine (AML). In comparison with a pepsin-poly(GMA-co-EDMA) monolithic column (without self-assembled ZIF-8 nanoparticles), the resolution is strongly enhanced (HCQ: 0.34 → 2.50; CHQ: 0.45 → 1.97; HXY: 0.39 → 1.43; NEF: 0.27 → 0.81; CLE: 0 → 0.81; AML: 0.16 → 0.72). Effects of self-assembly layers of ZIF-8, pepsin concentration, buffer pH values and applied voltage were investigated with hydroxychloroquine as the model analyte. The reproducibility of run-to-run, day-to-day and column-to-column were explored, and found to be satisfactory. Graphical abstractSchematic representation of capillary electrochromatography (CEC) systems with a pepsin-zeolitic imidazolate framework-8 (ZIF-8) modified poly(glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monolithic column as stationary phases for separation of basic racemic drugs. ZIF-8 modified column was prepared via layer-by-layer self-assembly.
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http://dx.doi.org/10.1007/s00604-019-3998-0DOI Listing
December 2019

Maltodextrin-modified graphene oxide for improved enantiomeric separation of six basic chiral drugs by open-tubular capillary electrochromatography.

Mikrochim Acta 2019 12 17;187(1):55. Epub 2019 Dec 17.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, No.24 Tongjiaxiang, Nanjing, Jiangsu, 210009, People's Republic of China.

An electrochromatographic capillary was modified with graphene oxide (GO), and the coating was characterized by scanning electron microscopy, energy dispersive X-ray spectrometry, and Fourier transform infrared spectra. By utilizing maltodextrin (MD) as the chiral selector, the basic chiral drugs nefopam (NEF), amlodipine (AML), citalopram hydrobromide (CIT), econazole (ECO), ketoconazole (KET) and cetirizine hydrochloride (CET) can be enantiomerically separated on this CEC. Compared with an uncoated silica capillary, the resolutions are markedly improved (AML: 0.32 → 1.45; ECO: 0.55 → 1.89; KET: 0.88 → 4.77; CET: 0.81 → 2.46; NEF: 1.46 → 2.83; CIT: 1.77 → 4.38). Molecular modeling was applied to demonstrate the mechanism of enantioseparation, which showed a good agreement with the experimental results. Graphical abstractSchematic representation of the preparation of graphene oxide-modified capillary (GO@capillary) for enantioseparation of drug enantiomers. The monolayered GO was used as the coating of the GO@capillary. Then the capillary was applied to construct capillary electrochromatography system with maltodextrin for separation of basic chiral drugs.
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http://dx.doi.org/10.1007/s00604-019-4037-xDOI Listing
December 2019

A rapid enantioseparation system of capillary electrochromatography modified by electrostatic adsorption with transfersomes.

Chirality 2020 01 16;32(1):98-106. Epub 2019 Nov 16.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, China.

Transfersomes were a special kind of nanomaterials with higher deformability and flexibility. A rapid method for coated-column preparation using anionic transfersomes as a coating material by electrostatic adsorption was developed. With carboxymethyl-β-cyclodextrin added in running buffer as the chiral selector, the capillary electrochromatography enantioseparation system based on the transfersomes-coated column modified by electrostatic adsorption was established for the first time. Propranolol and metoprolol acted as model drugs to evaluate the enantioseparation performance, these two basic drugs achieved baseline separation with satisfactory resolution and selection factor in this transfersomes-electrochromatography system but only partial separation in bare column system. In order to get the optimal separation condition, concentration of chiral selector, buffer pH, and applied voltage were systematically investigated. A rapid and efficient enantioseparation electrochromatography system was established and showed that transfersomes as the stationary phase could efficiently improve chiral separation effect.
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http://dx.doi.org/10.1002/chir.23145DOI Listing
January 2020

Enantioseparation of amino alcohol drugs by nonaqueous capillary electrophoresis with a maltobionic acid-based ionic liquid as the chiral selector.

Analyst 2019 Dec;144(24):7468-7477

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P. R. China.

This study deals with the nonaqueous capillary electrophoretic enantioseparation of twenty-two amino alcohol drugs with a maltobionic acid (MA)-based ionic liquid (tetramethylammonium maltobionic acid, TMA-MA) as the novel chiral selector. In consideration of the poor solubility of MA in organic solvents, we managed to transform MA into ionic liquids (ILs) for the first time. Interestingly, this chiral selector exhibited powerful enantioselectivity towards the model analytes in company with boric acid. Systematical experiments were carried out to investigate the influence of concentration of TMA-MA, boric acid and tris (hydroxymethyl) aminomethane (Tris) as well as applied voltage on the enantioseparation. A great majority of enantiomers (except labetalol) were baseline separated under the optimized conditions and the effect of the molecular structure of amino alcohol drugs on the chiral separation was discussed. In addition, electrophoretic experiments, nuclear magnetic resonance (NMR), mass spectrometry (MS) and molecular modeling with the Gaussian program were employed to demonstrate the mechanism of chiral recognition. Based on the formation of an ionic liquid-boric acid-analyte complex, hydrogen binding was mainly responsible for enantioseparation.
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http://dx.doi.org/10.1039/c9an01162eDOI Listing
December 2019

Preparation of Ag Doped Keratin/PA6 Nanofiber Membrane with Enhanced Air Filtration and Antimicrobial Properties.

Polymers (Basel) 2019 Sep 16;11(9). Epub 2019 Sep 16.

College of Textile and Garments, Hebei University of Science and Technology, Shijiazhuang 050018, China.

Coarse wool is a kind of goat wool that is difficult to further process in the textile industry due to its large diameter, dispersion, better strength, and less bending. Therefore, coarse wool is often discarded as waste or made into low-cost products. In this work, keratin was extracted from coarse wool by a high-efficiency method, and then, an Ag-doped keratin/PA6 composite nanofiber membrane with enhanced filtration and antibacterial performance was prepared using HCOOH as solvent and reductant. HAADF-STEM (high-angle annular dark field-scanning transmission electron microscopy) shows that AgNPs are uniformly distributed in keratin/PA6 (30/70) nanofibers. TGA (Thermogravimetric Analysis) and DSC (Differential Scanning Calorimetry) were employed to investigate the thermal stability of composite membranes with different keratin and AgNP contents. The present keratin as a dopant with polyamide-6 (PA6) was found not only to improve air filtration efficiency but also to enhance water-vapour transmission (WVT). The addition of the Ag nanoparticles (AgNPs) gave a strong antibacterial activity to the composite membrane against (99.62%) and (99.10%). Bacterial filtration efficiency (BFE) of the composite membrane against . and . were up to 96.8% and 95.6%, respectively. All of the results suggested a great potential for coarse wool extraction and application in the air filtration field.
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http://dx.doi.org/10.3390/polym11091511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6780504PMC
September 2019

An organic polymer monolith modified with an amino acid ionic liquid and graphene oxide for use in capillary electrochromatography: application to the separation of amino acids, β-blockers, and nucleotides.

Mikrochim Acta 2019 08 20;186(9):636. Epub 2019 Aug 20.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, No.24 Tongjiaxiang, Nanjing, Jiangsu, 210009, People's Republic of China.

The preparation of an organic polymer monolithic column modified with an amino acid ionic liquid and graphene oxide (AAIL-GO) and its application to capillary electrochromatography (CEC) was described. The AAIL tetramethylammonium-L-arginine was bonded to a monolithic column that was previously modified with graphene oxide by using an hydrochloride/N-hydroxysuccinimide coupling reaction. The morphology of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was examined by scanning electron microscopy. The incorporation of AAIL and graphene oxide was detected by infrared spectroscopy and elemental analysis. The resulting monolithic column produced a strong and stable electroosmotic flow from the anode to the cathode in the pH range from 3 to 9. Compared with a column modified with AAIL or graphene oxide only, the AAIL-GO-modified column has a better separation ability for amino acids, β-blockers, and nucleotides (the resolution of three amino acids: 2.231 and 2.036, β-blockers: 2.779 and 2.470 and nucleotides: 8.345 and 3.321). Molecular modeling was applied to demonstrate the separation mechanism of small molecules which showed a good support for experimental results. Graphical abstract Schematic representation of capillary electrochromatography (CEC) systems with an amino acid ionic liquid-graphene oxide modified organic polymer monolithic column as stationary phases for separation of amino acids, β-blockers, and nucleotides.
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http://dx.doi.org/10.1007/s00604-019-3723-zDOI Listing
August 2019

Sulfo-functional 3D porous cellulose/graphene oxide composites for highly efficient removal of methylene blue and tetracycline from water.

Int J Biol Macromol 2019 Nov 14;140:119-128. Epub 2019 Aug 14.

School of Pharmacy, Jiangxi Science and Technology Normal University, Nanchang, Jiangxi 330013, China. Electronic address:

Cellulose/graphene oxide (CG) porous composites with 3D network structure were prepared via a solution mixing-regeneration and freeze-drying process. The CG aerogels were functionalized with 1,4-butane sultone under mild reaction conditions to achieve sulfated composite aerogels (SCGs), in which the sulfo groups were simultaneously introduced onto GO and cellulose components. The adsorption ability of SCG aerogel was greatly enhanced compared with CG aerogels. The fitting results of adsorption models suggested the monolayer adsorption and chemisorptive characteristics with the maximal uptake capacity as high as 421.9 mg/g for methylene blue (MB) and 163.4 mg/g for tetracycline (TC). The adsorption mechanism was also studied in detail. For the simulated wastewater containing MB and TC, the novel SCG adsorbent exhibited a removal efficiency of 99%. Furthermore, its adsorption capacity was not apparently deteriorated after seven cycles for MB and ten cycles for TC while the original structural integrity was almost maintained. Herein, this recyclable and reusable adsorbent exhibited the potential application on the removal of MB and TC from water.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.08.111DOI Listing
November 2019

Correction to: Metal organic framework HKUST-1 modified with carboxymethyl-β-cyclodextrin for use in improved open tubular capillary electrochromatographic enantioseparation of five basic drugs.

Mikrochim Acta 2019 Aug 15;186(9):626. Epub 2019 Aug 15.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, People's Republic of China.

The published version of this article, unfortunately, contains error. The author found out that the given name interchanged with the family name. The second author's family name should be "Yu" and the first name should be "Tao". Given in this article is the correct author name.
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http://dx.doi.org/10.1007/s00604-019-3716-yDOI Listing
August 2019

Evaluation of an ionic liquid chiral selector based on clindamycin phosphate in capillary electrophoresis.

Anal Bioanal Chem 2019 Sep 8;411(22):5855-5866. Epub 2019 Jul 8.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.

Recently, increasing attention has been given to the research on chiral ionic liquids (CILs) in chiral separation field; however, only a few literatures focus on the exploration of CILs as the sole chiral selector. In this study, an ionic liquid chiral selector based on antibiotic, namely tetramethylammonium clindamycin phosphate (TMA-CP), was originally synthesized and subsequently utilized for enantioseparation in capillary electrophoresis (CE). Remarkably improved separations of eight racemic analytes were achieved in TMA-CP system in contrast to the clindamycin phosphate (CP) system. The optimal separation conditions were determinated by systematic experiments on several crucial parameters including the type and proportion of organic modifier, CIL concentration, buffer pH, and applied voltage. Additionally, molecular modeling with AutoDock was applied to probe into the chiral recognition mechanism of the ionic liquid chiral selectors, which well corresponded with the experimental results. It is the first time that antibiotic-based ionic liquid was exploited as favorable sole chiral selector in CE, and this strategy has paved a new way for development of novel ionic liquids chiral selectors based on antibiotics. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-019-01967-zDOI Listing
September 2019

Metal organic framework HKUST-1 modified with carboxymethyl-β-cyclodextrin for use in improved open tubular capillary electrochromatographic enantioseparation of five basic drugs.

Mikrochim Acta 2019 06 21;186(7):462. Epub 2019 Jun 21.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, People's Republic of China.

This work shows that the metal organic framework (MOF) HKUST-1 of type Cu(BTC) (also referred to as MOF-199; a face-centered-cubic MOF containing nanochannels) is a most viable coating for use in enantioseparation in capillary electrochromatography (CEC). A HKUST-1 modified capillary was prepared and characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, elemental analysis and thermogravimetric analysis. CEC-based enantioseparation of the basic drugs propranolol (PRO), esmolol (ESM), metoprolol (MET), amlodipine (AML) and sotalol (SOT) was performed by using carboxymethyl-β-cyclodextrin as the chiral selector. Compared with a fused-silica capillary, the resolutions are improved (ESM: 1.79; MET: 1.80; PRO: 4.35; SOT: 1.91; AML: 2.65). The concentration of chiral selector, buffer pH value, applied voltage and buffer concentration were optimized, and the reproducibilities of the migration times and R values were evaluated. Graphical abstract Schematic presentation of the preparation of a HKUST-1@capillary for enantioseparation of racemic drugs. Cu(NO) and 1,3,5-benzenetricarboxylic acid (BTC) were utilized to prepare the HKUST-1@capillary. Then the capillary was applied to construct capillary electrochromatography system with carboxymethyl-β-cyclodextrin (CM-β-CD) for separation of basic racemic drugs.
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http://dx.doi.org/10.1007/s00604-019-3584-5DOI Listing
June 2019

Occupational exposure to respirable dust from the coal-fired power generation process: sources, concentration, and health risk assessment.

Arch Environ Occup Health 2020 18;75(5):260-273. Epub 2019 Jun 18.

Sustainable Minerals Institute, University of Queensland, Brisbane, Australia.

To investigate the contamination levels of respirable dust released in the work environment and the induced workers' health risk at a coal-fired power plant, we collected 405 dust samples from different dusty workstations by personal sampling during the coal-fired power generation process. Then, an inhalation risk assessment model from the USEPA was combined with the Monte Carlo simulation method to quantitatively evaluate the health risk caused by dust inhalation. Of 10 workstations researched, the dust concentration in the most workstations exceeded the prescribed occupational exposure limit. Workers engaged in ash removal suffered the highest health risk at 4.08 × 10 ± 2.85 × 10 (95% CI), closely followed by those involved in other job categories. The results can contribute to the formulation of targeted dust prevention measures and implementation of risk management for the coal-fired power sector.
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http://dx.doi.org/10.1080/19338244.2019.1626330DOI Listing
August 2020